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1.
Front Oncol ; 14: 1342262, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38756661

RESUMO

Objective: To investigate the correlation between programmed death ligand 1(PD-L1), tumor mutation burden (TMB) and the short-term efficacy and clinical characteristics of anti-PD-1 immune checkpoint inhibitor combination chemotherapy in NSCLC patients. The efficacy of the prediction model was evaluated. Methods: A total of 220 NSCLC patients receiving first-line treatment with anti-PD-1 immune checkpoint inhibitor combined with chemotherapy were retrospectively collected. The primary endpoint was short-term efficacy ORR. The correlation between short-term efficacy, PD-L1, TMB, and clinical characteristics using χ2 test or t-test was evaluated. Screen the independent prognostic factors using univariate and multivariate logistic regression analyses, and construct a nomogram prediction model using the "rms" package in R software. Using receiver operating characteristic (ROC) curve analysis to evaluate the independent Prognostic factors and the prediction model. Using decision curve analysis (DCA) to verify the superiority of the prediction model. Results: The mean values of PD-L1, TMB, neutrophils, lymphocytes, neutrophil-to-lymphocyte ratio, and albumin were the highest in the ORR group, PD-L1 expression and TMB correlated with epidermal growth factor receptor expression. Multivariate analyses showed that PD-L1, TMB, and neutrophil were independent prognostic factors for ORR. The area under the ROC curve (AUC) values of the ROC constructed based on these three indicators were 0.7104, 0.7139, and 0.7131, respectively. The AUC value under the ROC of the nomogram model was 0.813. The DCA of the model showed that all three indicators used together to build the prediction model of the net return were higher than those of the single indicator prediction model. Conclusion: PD-L1, TMB, and neutrophils are independent prognostic factors for short-term efficacy. The nomogram prediction model constructed using these three indicators can further improve predictive efficacy of ICIs in patients with NSCLC.

2.
Anal Chem ; 96(19): 7730-7737, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38703107

RESUMO

A highly sensitive photoacoustic detection system using a differential Helmholtz resonator (DHR) combined with a Herriott multipass cell is presented, and its implementation to sub-ppm level carbon dioxide (CO2) detection is demonstrated. Through the utilization of erbium-doped optical fiber amplifier (EDFA), the laser power was amplified to 150 mW. Within the multipass cell, a total of 22 reflections occurred, contributing to an impressive 33.6 times improvement in the system sensitivity. The normalized noise equivalent absorption coefficient (NNEA) was 8.64 × 10-11 cm-1·W·Hz-1/2 [signal-to-noise ratio, (SNR) = 1] and according to the Allan variance analysis, a minimum detection limit of 500 ppb could be achieved for CO2 at 1204 s, which demonstrates the long-term stability of the system. The system was applied to detect the respiration of rice and upland rice seeds. It is demonstrated that the system can monitor and distinguish the respiration intensity and respiration rate of different seeds in real time.

3.
Sensors (Basel) ; 24(10)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38793959

RESUMO

Thin copper plate is widely used in architecture, transportation, heavy equipment, and integrated circuit substrates due to its unique properties. However, it is challenging to identify surface defects in copper strips arising from various manufacturing stages without direct contact. A laser ultrasonic inspection system was developed based on the Lamb wave (LW) produced by a laser pulse. An all-fiber laser heterodyne interferometer is applied for measuring the ultrasonic signal in combination with an automatic scanning system, which makes the system flexible and compact. A 3-D model simulation of an H62 brass specimen was carried out to determine the LW spatial-temporal wavefield by using the COMSOL Multiphysics software. The characteristics of the ultrasonic wavefield were extracted through continuous wavelet transform analysis. This demonstrates that the A0 mode could be used in defect detection due to its slow speed and vibrational direction. Furthermore, an ultrasonic wave at the center frequency of 370 kHz with maximum energy is suitable for defect detection. In the experiment, the size and location of the defect are determined by the time difference of the transmitted wave and reflected wave, respectively. The relative error of the defect position is 0.14% by averaging six different receiving spots. The width of the defect is linear to the time difference of the transmitted wave. The goodness of fit can reach 0.989, and it is in good agreement with the simulated one. The experimental error is less than 0.395 mm for a 5 mm width of defect. Therefore, this validates that the technique can be potentially utilized in the remote defect detection of thin copper plates.

4.
Sensors (Basel) ; 23(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37837080

RESUMO

Laser gas sensors with small volume and light weight are in high demand in the aerospace industry. To address this, a coin-sized oxygen (O2) sensor has been successfully developed based on a small toroidal absorption cell design. The absorption cell integrates a vertical-cavity surface-emitting laser (VCSEL) and photodetector into a compact unit, measuring 90 × 40 × 20 mm and weighing 75.16 g. Tunable diode laser absorption spectroscopy (TDLAS) is used to obtain the O2 spectral line at 763 nm. For further improving the sensitivity and robustness of the sensor, wavelength modulation spectroscopy (WMS) is utilized for the measurement. The obtained linear correlation coefficient is 0.9994. Based on Allen variance analysis, the sensor achieves an impressive minimum detection limit of 0.06% for oxygen concentration at an integration time of 318 s. The pressure-dependent relationship has been validated by accounting for the pressure factor in data processing. To affirm its efficacy, the laser spectrometer underwent continuous atmospheric O2 measurement for 24 h, showcasing its stability and robustness. This development introduces a continuous online laser spectral sensor with potential applications in manned spaceflight scenarios.

5.
Front Psychol ; 13: 974576, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36032997

RESUMO

In order to improve education and teaching methods and meet the "heart" needs of college students in the era of big data, this paper analyzes the application of data mining technology in college mental health education, and introduces database technology and decision tree algorithm to support college mental health work. This process verifies the feasibility of this kind of system with the help of an example. Using the test standards outlined in this document, 1.5 previous test tasks were completed within the timeframe. During the system test, the error rate was 14% and the number of tests was 7%.However, the error rate in the development stage is 11%, which is lower than 19% of the old version. The error rate in the acceptance stage is 14%, which is lower than 5% of the old version. That is to say, most of the errors were found in time in the system analysis and design stage. 14% of the problems found in the development stage are basically small problems in the interface display, which do not need major changes. However, the old version also includes design defects found in the development stage, and only large-scale rewriting of the involved modules. In the research process, the work of mental health in Colleges and universities has been promoted. At this time, the law of psychological changes of college students has been summarized. Therefore, the support of data mining technology can better meet the needs of mental health education in Colleges and universities.

6.
Opt Lett ; 47(3): 533-536, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103674

RESUMO

A squeezed state with higher-order sidebands is a valuable quantum resource for channel multiplexing quantum communication. However, balanced homodyne detection used in nonclassical light detection has a trade-off performance between the detection bandwidth and clearance, in which the verification of a highly squeezing factor faces a challenge. Here, we construct two optical parametric amplifiers with cavity enhancement; one is for the generation of a -10.5 dB squeezed vacuum state, and the other is for all-optical phase-sensitive parametric homodyne detection. Finally, -6.5 dB squeezing at the carrier with 17 pairs of squeezing sidebands (bandwidth of 156 GHz) is directly and simultaneously observed. In particular, for the cavity-enhanced parametric oscillation and detection processes, we analyze the limiting factors of the detectable bandwidth and measurement deviation from the generated value, which indicates that the length difference and propagation loss between two optical parametric amplifiers should be as small as possible to improve the detection performance. The experimental results confirm our theoretical analysis.

7.
Aging (Albany NY) ; 13(12): 15801-15814, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34182540

RESUMO

Coronavirus disease-2019 (COVID-19) has rapidly spread worldwide and causes high mortality of elderly patients. High-flow nasal cannula therapy (HFNC) is an oxygen delivery method for severely ill patients. We retrospectively analyzed the course of illness and outcomes in 110 elderly COVID-19 patients (≥65 years) treated with HFNC from 6 hospitals. 38 patients received HFNC (200 mmHg < PaO2/FiO2 ≤ 300 mmHg, early HFNC group), and 72 patients received HFNC (100 mmHg < PaO2/FiO2 ≤ 200 mmHg, late HFNC group). There were no significant differences of sequential organ failure assessment (SOFA) scores and APECH II scores between early and late HFNC group on admission. Compared with the late HFNC group, patients in the early HFNC group had a lower likelihood of developing severe acute respiratory distress syndrome (ARDS), longer time from illness onset to severe ARDS and shorter duration of viral shedding after illness onset, as well as shorter lengths of ICU and hospital stay. 24 patients died during hospitalization, of whom 22 deaths (30.6%) were in the late HFNC group and 2 (5.3%) in the early HFNC group. The present study suggested that the outcomes were better in severely ill elderly patients with COVID-19 receiving early compared to late HFNC.


Assuntos
COVID-19/complicações , Cânula , Oxigenoterapia/instrumentação , Síndrome do Desconforto Respiratório/terapia , Síndrome do Desconforto Respiratório/virologia , Idoso , COVID-19/mortalidade , COVID-19/terapia , China , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva , Tempo de Internação/estatística & dados numéricos , Modelos Logísticos , Masculino , Análise Multivariada , Síndrome do Desconforto Respiratório/mortalidade , Estudos Retrospectivos
8.
Opt Lett ; 46(8): 1844-1847, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33857087

RESUMO

To scale quantum information processing, quantum state distributors are an indispensable technology in quantum networks. We present a universal scheme of a continuous variable quantum state distributor that performs point-to-multipoint distributions via quantum teleportation with partially disembodied transport. The fidelity of the state at the output nodes can be conveniently manipulated as needed by engineering the correlation noise of the Einstein-Podolsky-Rosen (EPR) beam. For a 1→2 distributor, controllable distributions were demonstrated by manipulating the squeezing factor of EPR entanglement. The fidelities of the two receivers gradually changed from (2/3, 2/3) to (0.95, 0.17) corresponding to the transition from symmetric to asymmetric quantum cloning.

11.
Opt Lett ; 45(8): 2419-2422, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32287248

RESUMO

We demonstrate the experimental detection of an optical squeezing covering several higher resonances of the optical parametric amplifier (OPA) by adopting a bichromatic local oscillator (BLO). The BLO is generated from a waveguide electro-optic phase modulator (WGM) and subsequent optical mode cleaner (OMC), without the need of additional power balance and phase control. The WGM is used for generating the frequency-shifted sideband beams with equal power and certain phase difference, and the OMC is used for filtering the unwanted optical modes. Among a measurement frequency range from 0 to 16.64 GHz, the maximum squeezing factors are superior to 10 dB below the shot noise limit for the first three discrete odd-order resonances of the OPA.

12.
Opt Lett ; 44(7): 1789-1792, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30933148

RESUMO

We demonstrate the dependence of the squeezing and anti-squeezing factors on the seed beam power at different pump beam noise levels. The results indicate that a seed field injected into the optical parametric amplifier (OPA) dramatically degenerates the squeezing factor due to noise coupling between the pump and seed fields, even if both the pump and seed fields reach the shot noise limit. The squeezing and anti-squeezing factors are immune to the pump beam noise due to no noise coupling when the system operates for the generation of squeezed vacuum states. The squeezing factor degrades gradually as the pump beam intensity noise and seed beam power is increased. The influence of the two orthogonal quadrature variations is mutually independent of each other.

13.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 30(9): 900-901, 2018 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-30309419

RESUMO

OBJECTIVE: Positive end-expiratory pressure (PEEP) is a common method to maintain alveolar patency in patients undergoing mechanical ventilation. However, in patients undergoing tracheotomy, alveolar collapse often occurs due to bedridden, aspiration, and other factors. There is currently no effective means to provide PEEP support for such patients. The application of a high-flow oxygen inhalation device with a PEEP valve was designed to provide patients with continuously adjustable PEEP, which helps to improve the patient's oxygenation and maintain the lung's physiological functions.


Assuntos
Oxigenoterapia/instrumentação , Respiração com Pressão Positiva/instrumentação , Desenho de Equipamento , Humanos , Respiração Artificial
14.
Opt Express ; 26(15): 18957-18968, 2018 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-30114155

RESUMO

We present an analysis on how the optical parametric oscillator (OPO) detuning and the relative phase drift deteriorate the stability of the squeezed states, including the output power and the squeezed degree, and investigate the influence of RAM on the cavity detuning and the relative phase drift under different cases. Subsequently, the RAM is experimentally measured. In term of the measurement results, we perform a comparative study about RAM's influence on the cavity and phase locking in two cases. As a result, with the error signal extracted from the transmission of the OPO, the output power stability of the squeezed light is greatly improved. With the phase modulation imposed on the signal beam, the long-term stability of the squeezed degree is significantly enhanced.

15.
Phytochemistry ; 149: 31-41, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29455054

RESUMO

Nine previously undescribed seco-labdane diterpenoids, nudiflopenes A-I, were isolated from the leaves of Callicarpa nudiflora. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analysis, and the absolute configurations of these compounds were established by the modified Mosher's method and experimental and calculated electronic circular dichroism spectra. Nudiflopenes A-I belong to the class of seco-labdane diterpenoids. All of the isolates showed inhibitory activities on lipopolysaccharide-induced nitric oxide (NO) production in murine microglial BV-2 cells. The possible mechanism of NO inhibition of some bioactive compounds was also investigated using molecular docking, which revealed interactions of bioactive compounds with the inducible nitric oxide synthase (iNOS) protein.


Assuntos
Callicarpa/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Folhas de Planta/química , Animais , Diterpenos/química , Medicamentos de Ervas Chinesas/química , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/metabolismo , Estrutura Molecular , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Ressonância Magnética Nuclear Biomolecular
16.
Exp Ther Med ; 13(6): 3594-3602, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28588686

RESUMO

Kidney injury molecule-1 (Kim-1) and neutrophil gelatinase-associated lipocalin (NGAL) have been investigated as biomarkers for acute kidney injury (AKI). However, they are seldom investigated in patients with septic AKI treated with continuous renal replacement therapy (CRRT). The aim of the present study was to investigate the therapeutic effectiveness and possible mechanisms of CRRT in septic AKI by observing the changes in Kim-1 and NGAL levels. A group of 38 patients with septic AKI was randomly divided into the conventional drug treatment group (group A) and the CRRT group (group B). All patients were treated with standard antisepsis agents, and group B was additionally submitted to CRRT for 24 h. The levels of Kim-1 and NGAL in serum, urine and the ultrafiltrate of CRRT were measured prior to and at 12, 24, and 48 h after treatment. In group A, urinary Kim-1 (uKim-1) levels at 12, 24 and 48 h were lower than prior to treatment (P<0.05), whereas urinary NGAL (uNGAL) showed no difference among the various time points (P>0.05). In group B, uKim-1 was decreased at 24 and 48 h compared with before treatment (all P<0.05), whereas uNGAL was decreased at 48 h (P<0.05). Serum Kim-1 did not change with time in groups A and B (P>0.05), whereas serum NGAL was increased after treatment in group A (P<0.05) but did not change in group B (P>0.05). Kim-1 and NGAL were not detected in the ultrafiltrate of CRRT. uKim-1 and uNGAL decreased significantly after CRRT, and therefore may be used to reflect the change of renal function during CRRT and to evaluate the therapeutic effectiveness of the method.

17.
Bioorg Med Chem Lett ; 27(3): 670-674, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-27989668

RESUMO

A phytochemical investigation to obtain new NO inhibitors resulted in the isolation of a new diterpenoid with a rare 9,10-seco-abietane skeleton (1) and twelve known terpenoids (2-13) from Callicarpa kwangtungensis. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analyses, and the absolute configuration of compound 1 was established by comparison of the calculated and experimental electronic circular dichroism (ECD) spectra. The inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells of these terpenoids were evaluated, and all of the compounds showed inhibitory effects. The following molecular docking studies showed interactions of the bioactive compounds with the iNOS protein.


Assuntos
Abietanos/química , Callicarpa/química , Diterpenos/química , Óxido Nítrico/metabolismo , Abietanos/isolamento & purificação , Abietanos/farmacologia , Animais , Sítios de Ligação , Callicarpa/metabolismo , Linhagem Celular , Dicroísmo Circular , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Camundongos , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Conformação Molecular , Simulação de Acoplamento Molecular , Óxido Nítrico Sintase Tipo II/química , Óxido Nítrico Sintase Tipo II/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Estrutura Terciária de Proteína
18.
J Nat Prod ; 79(11): 2924-2932, 2016 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-27933899

RESUMO

A phytochemical investigation to obtain new NO inhibitors resulted in the identification of six new (1-6) and four known (7-10) terpenoids from Salvia plebeia. Compounds 1 and 2 are new diterpenoids, 3-5 are new meroditerpenoids, 6-9 are sesquiterpenoids, and 10 is a known meroditerpenoid. The structures of these isolates were determined by routine NMR experiments and X-ray diffraction, as well as the electronic circular dichroism spectra. Compounds 1-4 are diterpenoids carrying an oxygen bridge, and 6 is a rare copane-type sesquiterpenoid with a bridged tricyclic framework. The isolates inhibited NO generation induced by lipopolysaccharide in BV-2 cells. The possible mechanism of NO inhibition of some bioactive compounds was also investigated using molecular docking, which revealed interactions of bioactive compounds with the iNOS protein.


Assuntos
Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico/antagonistas & inibidores , Salvia/química , Cristalografia por Raios X , Diterpenos/química , Medicamentos de Ervas Chinesas/química , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Conformação Molecular , Simulação de Acoplamento Molecular , Estrutura Molecular , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
19.
Fitoterapia ; 113: 151-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27491749

RESUMO

A phytochemical investigation of the leaves of Callicarpa kwangtungensis led to the isolation of three new diterpenoids (1-3), callipenes A-C, and eleven known analogues (4-14). Their structures were established on the basis of extensive analysis of NMR spectroscopic data, X-ray diffraction data, and experimental and calculated electronic circular dichroism spectra. Compounds 1 and 2 are rare abietane diterpenoids possessing a peroxide bridge. All of the isolates were found to inhibit LPS-induced NO production in BV-2 cells.


Assuntos
Abietanos/química , Callicarpa/química , Diterpenos/química , Óxido Nítrico/metabolismo , Abietanos/isolamento & purificação , Animais , Linhagem Celular , Diterpenos/isolamento & purificação , Camundongos , Estrutura Molecular , Folhas de Planta/química
20.
Bioorg Med Chem Lett ; 26(19): 4785-4789, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27570243

RESUMO

A phytochemical investigation to obtain new NO inhibitors led to the isolation of two new (1 and 2) and four known (3-6) diterpenoids from Trigonostemon chinensis. Their structures were elucidated on the basis of extensive 1D and 2D NMR spectroscopic data analyses, and the absolute configurations of new compounds were established by experimental and calculated ECD spectra. The inhibitory activities on lipopolysaccharide-induced NO production in murine microglial BV-2 cells of these diterpenoids were evaluated, and all of the compounds showed inhibitory effects. The interactions of bioactive compounds with iNOS protein were also studied by molecular docking.


Assuntos
Diterpenos/química , Diterpenos/farmacologia , Euphorbiaceae/química , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico/antagonistas & inibidores , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
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