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1.
Anal Chem ; 96(37): 14877-14883, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39219057

RESUMO

Greenhouse gas (GHG) detection plays an important role in climate change research and industry applications. A novel photoacoustic spectroscopy (PAS) sensor based on multiple resonators has been developed for the detection of GHGs. The major GHGs CO2, CH4, and N2O were measured simultaneously using only one acoustic sensor by coupling three acoustic resonators into a photoacoustic cell. A sinusoidal voltage signal-driven noise source was integrated into a multiresonator photoacoustic cell, allowing convenient calibration of the resonant frequency of the photoacoustic cell. The performance of the sensor was further enhanced by reflecting a laser beam four times in the photoacoustic cell. Allan deviation analysis showed that the minimum detection limits of 2.7 ppm, 90 ppb, and 1 ppb could be achieved for CO2, CH4, and N2O, respectively, over a 300 s integration time. The feasibility of the system was confirmed by continuous measurements of the three major GHGs from different sources for up to 10 h.

2.
Opt Lett ; 49(4): 1033-1036, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359246

RESUMO

Pressure is an important parameter in assessing combustion performance that is typically measured using contact sensors. However, contact sensors usually disturb combustion flows and suffer from the temperature tolerance limit of sensor materials. In this Letter, an innovative noncontact two-color pressure sensing method based on tunable diode laser absorption spectroscopy (TDLAS) is proposed. This makes it possible to measure pressure at high temperature environments for combustion diagnostics. The proposed method uses the linear combination of the collision-broadened linewidths of two H2O absorption lines near 1343 and 1392 nm to measure the pressure. The feasibility and performance of such method have been demonstrated by measuring pressures from 1 to 5 bars at temperatures up to 1300 K with a laser wavelength scanning rate of 20 kHz. Measurement errors were found to be within 3%. Compared to previously reported TDLAS pressure sensors, this method is free from the influence of concentration and can also be combined with the existing two-color TDLAS thermometry to realize a fast, on line, and multi-parameter measurement in combustion diagnostics.

3.
Phys Chem Chem Phys ; 26(21): 15705-15716, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38766741

RESUMO

The electrochemical NH3 synthesis on TiNO is proposed to follow the Mars-van Krevelen (MvK) mechanism, offering more favorable N2 adsorption and activation on the N vacancy (Nv) site, compared to the conventional associative mechanism. The regeneration cycle of Nv represents the rate-determining step in this process. This study investigates a series of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, and Pt)-TiNO to explore the *H migration (from TM to TiNO)-promoted Nv cycle. The screening results indicate that Ni-TiNO exhibits strong H2O decomposition for *H production with 0.242 eV and low *H migration resistance with 0.913 eV. Notably, *H migration from Ni to TiNO significantly reduces the Nv formation energy to 0.811 eV, compared to 1.387 eV on pure TiNO. Meanwhile, in the presence of *H, Nv formation takes precedence over Tiv and Ov. Lastly, electronic performance calculations reveal that the collaborative function provided by Ni and Nv enables highly stable and efficient NH3 synthesis. The *H migration-assisted MvK mechanism demonstrates effective catalytic cycle performance in electrochemical N2 fixation and may have potential applicability to other hydrogenation reactions utilizing water as a proton source.

4.
Phys Chem Chem Phys ; 26(8): 7166-7176, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38349087

RESUMO

The Volmer step in alkaline hydrogen evolution reactions (HERs), which supplies H* to the following steps by cleaving H-O-H bonds, is considered the rate-determining step of the overall reaction. The Volmer step involves water dissociation and adsorbed hydroxyl (*OH) desorption; Ru-based catalysts display a compelling water dissociation process in an alkaline HER. Unfortunately, the strong affinity of Ru for *OH blocks the active sites, resulting in unsatisfactory performance during HER processes. Hence, this study investigates a series of key descriptors (ΔG*H2O, ΔG*H-OH, ΔG*H, and ΔG*OH) of TM (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, or Pt)-Ru/Mo2Ti2C3O2 to systematically explore the effects of bimetallic site interactions on the kinetics of the Volmer step. The results indicate that bimetallic catalysts effectively reduced the strong adsorption of *OH on Ru sites; especially, the NiRu diatomic state shows the highest electron-donating ability, which promoted the smooth migration of *OH from Ru sites to Ni sites. Therefore, Ru, Ni and MXenes are suitable to serve as water adsorption and dissociation sites, *OH desorption sites, and H2 release sites, respectively. Ultimately, NiRu/Mo2Ti2C3O2 promotes Volmer kinetics and has the potential to improve alkaline HERs. This work provides theoretical support for the construction of synergistic MXene-based diatomic catalysts and their wide application in the field of alkaline HERs.

5.
Cell Mol Life Sci ; 80(11): 341, 2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37898977

RESUMO

Following myocardial ischemic injury, the most effective clinical intervention is timely restoration of blood perfusion to ischemic but viable myocardium to reduce irreversible myocardial necrosis, limit infarct size, and prevent cardiac insufficiency. However, reperfusion itself may exacerbate cell death and myocardial injury, a process commonly referred to as ischemia/reperfusion (I/R) injury, which primarily involves cardiomyocytes and cardiac microvascular endothelial cells (CMECs) and is characterized by myocardial stunning, microvascular damage (MVD), reperfusion arrhythmia, and lethal reperfusion injury. MVD caused by I/R has been a neglected problem compared to myocardial injury. Clinically, the incidence of microvascular angina and/or no-reflow due to ineffective coronary perfusion accounts for 5-50% in patients after acute revascularization. MVD limiting drug diffusion into injured myocardium, is strongly associated with the development of heart failure. CMECs account for > 60% of the cardiac cellular components, and their role in myocardial I/R injury cannot be ignored. There are many studies on microvascular obstruction, but few studies on microvascular leakage, which may be mainly due to the lack of corresponding detection methods. In this review, we summarize the clinical manifestations, related mechanisms of MVD during myocardial I/R, laboratory and clinical examination means, as well as the research progress on potential therapies for MVD in recent years. Better understanding the characteristics and risk factors of MVD in patients after hemodynamic reconstruction is of great significance for managing MVD, preventing heart failure and improving patient prognosis.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Humanos , Células Endoteliais/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Insuficiência Cardíaca/metabolismo
6.
Cell Mol Biol Lett ; 29(1): 123, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277732

RESUMO

BACKGROUND: Loss-of-function mutations of ZBTB24 cause immunodeficiency, centromeric instability, and facial anomalies syndrome 2 (ICF2). ICF2 is a rare autosomal recessive disorder with immunological defects in serum antibodies and circulating memory B cells, resulting in recurrent and sometimes fatal respiratory and gastrointestinal infections. The genotype-phenotype correlation in patients with ICF2 indicates an essential role of ZBTB24 in the terminal differentiation of B cells. METHODS: We used the clustered regularly interspaced short palindromic repeats (CRISPER)/Cas9 technology to generate B cell specific Zbtb24-deficient mice and verified the deletion specificity and efficiency by quantitative polymerase chain reaction (Q-PCR) and western blotting analyses in fluorescence-activated cell sorting (FACS)-sorted cells. The development, phenotype of B cells and in vivo responses to T cell dependent or independent antigens post immunization were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Adoptive transfer experiment in combination with in vitro cultures of FACS-purified B cells and RNA-Seq analysis were utilized to specifically determine the impact of Zbtb24 on B cell biology as well as the underlying mechanisms. RESULTS: Zbtb24 is dispensable for B cell development and maintenance in naive mice. Surprisingly, B cell specific deletion of Zbtb24 does not evidently compromise germinal center reactions and the resulting primary and secondary antibody responses induced by T cell dependent antigens (TD-Ags), but significantly inhibits T cell independent antigen-elicited antibody productions in vivo. At the cellular level, Zbtb24-deficiency specifically impedes the plasma cell differentiation of B1 cells without impairing their survival, activation and proliferation in vitro. Mechanistically, Zbtb24-ablation attenuates heme biosynthesis partially through mTORC1 in B1 cells, and addition of exogenous hemin abrogates the differentiation defects of Zbtb24-null B1 cells. CONCLUSIONS: Zbtb24 seems to regulate antibody responses against TD-Ags B cell extrinsically, but it specifically promotes the plasma cell differentiation of B1 cells via heme synthesis in mice. Our study also suggests that defected B1 functions contribute to recurrent infections in patients with ICF2.


Assuntos
Diferenciação Celular , Doenças da Imunodeficiência Primária , Fatores de Transcrição , Animais , Camundongos , Linfócitos B/imunologia , Linfócitos B/metabolismo , Face/anormalidades , Síndromes de Imunodeficiência/genética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças da Imunodeficiência Primária/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição/metabolismo
7.
BMC Ophthalmol ; 24(1): 435, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39367384

RESUMO

PURPOSE: To evaluate the effectiveness and safety of a method for repairing an eroded Ahmed glaucoma valve (AGV) tube using two short scleral tunnels made in tandem with a 22G needle instead of covering the eroded tube with another scleral graft. METHODS: From May 12, 2015, to July 27, 2019, we retrospectively reviewed eight patients at Ningbo Aier Eye Hospital who developed AGV tube erosion secondary to necrosis of their overlying conjunctiva and scleral grafts. This defect was repaired in all the patients using the double short tandem scleral tunnel technique, which involved the creation of double short tandem scleral tunnels made by a 22G needle. Two parallel-to-limbus scleral incisions were made 3 mm and 6 mm from the limbus first, then a curved 22G needle was inserted between the two scleral cuts to make one scleral tunnel, the other scleral tunnel was completed during the first surgery, inserted the tube into the two tunnels. The mean length of time between the AGV placement and the first erosion was 12.25 ± 6.36 months (3-24 months). The mean age of the patients was 65.50 ± 11.70 years (49-78 years). RESULTS: The surgical outcome was assessed in terms of the tectonic integrity of the conjunctiva over the follow-up period (12 months). There was no AGV tube erosion, scleral thinning, or ocular infection after a mean of 41.25 ± 26.54 months of follow-up in all eight patients. CONCLUSION: AGV tube erosion following shunt surgery can be successfully managed using the improved double short tandem scleral tunnel technique.


Assuntos
Implantes para Drenagem de Glaucoma , Glaucoma , Pressão Intraocular , Esclera , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Masculino , Feminino , Esclera/cirurgia , Idoso , Glaucoma/cirurgia , Pressão Intraocular/fisiologia , Túnica Conjuntiva/cirurgia , Seguimentos , Falha de Prótese , Acuidade Visual
8.
Mediators Inflamm ; 2024: 6626706, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38576857

RESUMO

Background: Observational researches reported the underlying correlation of plasma myeloperoxidase (MPO) concentration with respiratory tract infections (RTIs), but their causality remained unclear. Here, we examined the cause-effect relation between plasma MPO levels and RTIs. Materials and Methods: Datasets of plasma MPO levels were from the Folkersen et al. study (n = 21,758) and INTERVAL study (n = 3,301). Summarized data for upper respiratory tract infection (URTI) (2,795 cases and 483,689 controls) and lower respiratory tract infection (LRTI) in the intensive care unit (ICU) (585 cases and 430,780 controls) were from the UK Biobank database. The primary method for Mendelian randomization (MR) analysis was the inverse variance weighted approach, with MR-Egger and weighted median methods as supplements. Cochrane's Q test, MR-Egger intercept test, MR pleiotropy residual sum and outliers global test, funnel plots, and leave-one-out analysis were used for sensitivity analysis. Results: We found that plasma MPO levels were positively associated with URTI (odds ratio (OR) = 1.135; 95% confidence interval (CI) = 1.011-1.274; P=0.032) and LRTI (ICU) (OR = 1.323; 95% CI = 1.006-1.739; P=0.045). The consistent impact direction is shown when additional plasma MPO level genome-wide association study datasets are used (URTI: OR = 1.158; 95% CI = 1.072-1.251; P < 0.001; LRTI (ICU): OR = 1.216; 95% CI = 1.020-1.450; P=0.030). There was no evidence of a causal effect of URTI and LRTI (ICU) on plasma MPO concentration in the reverse analysis (P > 0.050). The sensitivity analysis revealed no violations of MR presumptions. Conclusions: Plasma MPO levels may causally affect the risks of URTI and LRTI (ICU). In contrast, the causal role of URTI and LRTI (ICU) on plasma MPO concentration was not supported in our MR analysis. Further studies are needed to identify the relationship between RTIs and plasma MPO levels.


Assuntos
Estudo de Associação Genômica Ampla , Infecções Respiratórias , Humanos , Análise da Randomização Mendeliana , Bases de Dados Factuais , Peroxidase
9.
Anal Chem ; 95(2): 1680-1685, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36602469

RESUMO

Faraday rotation spectroscopy (FRS) exploits the magneto-optical effect to achieve highly selective and sensitive detection of paramagnetic molecules. Usually, a solenoid coil is used to provide a longitudinal magnetic field to produce the magneto-optical effect. However, such a method has the disadvantages of excessive power consumption and susceptibility to electromagnetic interference. In the present work, a novel FRS approach based on a combination of a neodymium iron boron permanent magnet ring array and a Herriott multipass absorption cell is proposed. A longitudinal magnetic field was generated by using 14 identical neodymium iron boron permanent magnet rings combined in a non-equidistant form according to their magnetic field's spatial distribution characteristics. The average magnetic field strength within a length of 380 mm was 346 gauss. A quantum cascade laser was used to target the optimum 441 ← 440 Q-branch nitrogen dioxide transition at 1613.25 cm-1 (6.2 µm) with an optical power of 40 mW. Coupling to a Herriott multipass absorption cell, a minimum detection limit of 0.4 ppb was achieved with an integration time of 70 s. The low-power FRS nitrogen dioxide sensor proposed in this work is expected to be developed into a robust field-deployable environment monitoring system.

10.
Small ; 19(12): e2206225, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36587970

RESUMO

Using CO2 , water, and sunlight to produce solar fuel is a very attractive process, which can synchronously reduce carbon and convert solar energy into hydrocarbons. However, photocatalytic CO2 reduction is often limited by the low selectivity of reduction products and poor photocatalytic activity. In this study, S-scheme Bi5 O7 I-OVs/Cd0.5 Zn0.5 S (Bi5 O7 I-OVs/CZS-0.5) heterojunction with strong interfacial electric field (IEF) is prepared by in situ growth method. The performance of reduction CO2 to CO is studied by continuous flow photothermal catalytic (PTC) CO2 reduction platform. 12.5% Bi5 O7 I-OVs/CZS-0.5 shows excellent CO yield of 58.6 µmol g-1  h-1 and selectivity of 98.4%, which are 35.1 times than that of CZS-0.5 under visible light. The charge transfer path of the S-scheme through theoretical calculation (DFT), in situ irradiation Kelvin probe force microscope (ISI-KPFM) and in situ irradiation X-ray photoelectron spectroscopy (ISI-XPS) analysis, is verified. The study can provide useful guidance and reference for improving activity by oxygen vacancy induced strong IEF and the development of a continuous flow PTC CO2 reduction system.

11.
Small ; 19(24): e2300717, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36919813

RESUMO

Regulating electronic structures of the active site by manipulating the local coordination is one of the advantageous means to improve photocatalytic hydrogen evolution (PHE) kinetics. Herein, the ZnIn2 S4 /Mo2 TiC2 Schottky junctions are designed to be constructed through the interfacial local coordination of In3+ with the electronegative O terminal group on Mo2 TiC2 based on the different work functions. Kelvin probe force microscopy and charge density difference reveal that an electronic unidirectional transport channel across the Schottky interface from ZnIn2 S4 to Mo2 TiC2 is established by the formed local nucleophilic/electrophilic region. The increased local electron density of Mo2 TiC2 inhibits the backflow of electrons, boosts the charge transfer and separation, and optimizes the hydrogen adsorption energy. Therefore, the ZnIn2 S4 /Mo2 TiC2 photocatalyst exhibits a superior PHE rate of 3.12 mmol g-1 h-1 under visible light, reaching 3.03 times that of the pristine ZnIn2 S4 . This work provides some insights and inspiration for preparing MXene-based Schottky catalysts to accelerate PHE kinetics.

12.
Opt Express ; 31(5): 7850-7862, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859908

RESUMO

We developed a near-infrared (NIR) dual-channel oxygen-corrected laser heterodyne radiometer (LHR) in the ground-based solar occultation mode for measuring vertical profile of wind field in the troposphere and low stratosphere. Two distributed feedback (DFB) lasers centered at 1.27 µm and 1.603 µm were used as local oscillators (LO) to probe absorption of oxygen (O2) and carbon dioxide (CO2), respectively. High-resolution atmospheric O2 and CO2 transmission spectra were measured simultaneously. The atmospheric O2 transmission spectrum was used to correct the temperature and pressure profiles based on a constrained Nelder-Mead's simplex method. Vertical profiles of atmospheric wind field with an accuracy of ∼5 m/s were retrieved based on the optimal estimation method (OEM). The results reveal that the dual-channel oxygen-corrected LHR has high development potential in portable and miniaturized wind field measurement.

13.
Opt Express ; 31(2): 3237-3248, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785320

RESUMO

A novel CH4 sensor based on wavelength modulation spectroscopy with a multipass cell was developed for the soil respiration measurement of CH4. A home-made double-enhanced Herriot-type multipass cell with an effective absorption length of 73.926 m and a fiber-coupled distributed feedback diode laser emission at 1653.74 nm were used to design the sensor. The double enhancement of the effective optical pathlength of the multipass cell, absorption line locking, laser intensity normalization, and temperature control of the multipass cell were used to improve cell performance and achieve a minimum detection limit of 10 ppbv and a measurement precision of 6.4 ppbv. Finally, the potential of the developed CH4 sensor for ecological applications was verified by measuring the soil respiration of CH4 and monitoring of CH4 in the atmosphere over a long period.

14.
Opt Express ; 31(6): 9251-9263, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157498

RESUMO

A near-infrared broadband (1500-1640 nm) laser heterodyne radiometer (LHR) with a tunable external-cavity diode laser as the local oscillator is developed and the relative transmittance, which represents the absolute relationship between the measured spectral signals and the atmospheric transmittance, is derived. High-resolution (0.0087 cm-1) LHR spectra in the spectral region of 6248.5-6256 cm-1 were recorded for the observation of atmospheric CO2. Combined with the relative transmittance, the preprocessed measured LHR spectra, the optimal estimation method, and the Python scripts for computational atmospheric spectroscopy, the column-averaged dry-air mixing ratio of CO2 of 409.09 ± 8 ppmv in Dunkirk, France on February 23, 2019, was retrieved, which is consistent with GOSAT and TCCON data. The near-infrared external-cavity LHR demonstrated in the present work has a high potential for use in developing a robust, broadband, unattended, and all-fiber LHR for spacecraft and ground-based atmospheric sensing that offers more channel selection for inversion.

15.
Sex Transm Infect ; 99(5): 311-316, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36104248

RESUMO

OBJECTIVES: To examine innate immunity predictors of HIV-1 acquisition as biomarkers of HSV-2 risk and biological basis for epidemiologically established HIV-1 predisposition in HSV-2 infected women. METHODS: We analysed longitudinal samples from HIV-1 negative visits of 1019 women before and after HSV-2 acquisition. We measured cervical and serum biomarkers of inflammation and immune activation previously linked to HIV-1 risk. Protein levels were Box-Cox transformed and ORs for HSV-2 acquisition were calculated based on top quartile or below/above median levels for all HSV-2 negative visits. Bivariate analysis determined the likelihood of HSV-2 acquisition by biomarker levels preceding infection. Linear mixed-effects models evaluated if biomarkers differed by HSV-2 status defined as negative, incident or established infections with an established infection cut-off starting at 6 months. RESULTS: In the cervical compartment, two biomarkers of HIV-1 risk (low SLPI and high BD-2) also predicted HSV-2 acquisition. In addition, HSV-2 acquisition was associated with IL-1ß, IL-6, IL-8, MIP-3α, ICAM-1 and VEGF when below median levels. Systemic immunity predictors of HSV-2 acquisition were high sCD14 and IL-6, with highest odds when concomitantly increased (OR=2.23, 1.49-3.35). Concomitant systemic and mucosal predictors of HSV-2 acquisition risk included (1) serum top quartile sCD14 with cervical low SLPI, VEGF and ICAM-1, or high BD-2; (2) serum high IL-6 with cervical low VEGF and ICAM-1, SLPI, IL-1ß and IL-6; and (3) serum low C reactive protein with cervical high BD-2 (the only combination also predictive of HIV-1 acquisition). Most cervical biomarkers were decreased after HSV-2 acquisition compared with the HSV-2 negative visits, with incident infections associated with a larger number of suppressed cervical biomarkers and lower serum IL-6 levels compared with established infections. CONCLUSIONS: A combination of systemic immunoinflammatory and cervical immunosuppressed states predicts HSV-2 acquisition. A persistently suppressed innate immunity during incident HSV-2 infection may add to the increased HIV-1 susceptibility.


Assuntos
Infecções por HIV , Soropositividade para HIV , Herpes Genital , Feminino , Humanos , Herpes Genital/epidemiologia , Herpes Genital/complicações , Herpesvirus Humano 2 , Infecções por HIV/complicações , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6 , Soroconversão , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptores de Lipopolissacarídeos , Soropositividade para HIV/complicações , Imunidade Inata , Biomarcadores
16.
Opt Lett ; 48(20): 5229-5232, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831834

RESUMO

A near-infrared (NIR) laser heterodyne radiometer (LHR) using a 1603 nm distributed feedback (DFB) laser, associated with an erbium-doped fiber amplifier (EDFA), used as a local oscillator (LO) was developed. The EDFA was customized for automatic power control to amplify and stabilize the LO DFB laser power, which allowed to reduce baseline fluctuation and thus make the processed atmospheric transmission spectrum with higher precision. The operation of the EDFA-assisted LHR with a shot-noise-dominated performance was analyzed and experimentally achieved by optimizing the LO power. The performance of the developed LHR was evaluated and verified by measuring an atmospheric CO2 absorption spectrum, and the atmospheric CO2 column abundances were then retrieved based on the optimal estimation method (OEM). The results were in good agreement with the Greenhouse Gas Observation Satellite (GOSAT) data. The EDFA-assisted LHR firstly reported in this Letter has a potential to further improve the measurement precision of atmospheric greenhouse gases using ground-based LHR remote sensing.

17.
AIDS Behav ; 27(3): 978-983, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36357806

RESUMO

The Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial found no substantial difference in HIV acquisition risk between women randomised to injectable intramuscular depot medroxyprogesterone acetate (DMPA-IM), copper intrauterine device (Cu-IUD) or the levonorgestrel (LNG) implant. We evaluated post-randomization sexual behavior using an objective marker of condomless vaginal sex in a subset of participants. We conducted a sub-study among 458 ECHO participants at three sites (Cape Town, Johannesburg, Kisumu) to evaluate the frequency of condomless vaginal sex, measured by prostate specific antigen (PSA) detection in vaginal swabs, collected at the month 6 and final visit and the concordance of self-reported condomless vaginal sex with PSA detection, by randomized arm. We compared PSA detection frequency and concordance of PSA and self-reported condomless vaginal sex, by randomized group using Cochran-Mantel-Haenszel tests and adjusted generalized logistic growth curve models. PSA was detected less frequently in the DMPA-IM (16%), compared to the Cu-IUD (21%) and LNG implant (24%) groups, although results were not statistically significant in the unadjusted model when accounting for pre-specified multiple-testing criteria. There were significant differences in PSA detection between the DMPA-IM and LNG-implant groups (odds ratio 0.61 (95% CI 0.40, 0.94) in the adjusted model. There was moderate discordance between self-reported condomless vaginal sex and detection of PSA that was similar across randomized groups. These data suggest that women randomized to Cu-IUD and LNG implant may have had condomless sex more frequently than women randomized to DMPA-IM. The discordance between detectable PSA and self-reported sexual behaviour has important implications for design of future HIV prevention studies.


Assuntos
Anticoncepcionais Femininos , Infecções por HIV , Dispositivos Intrauterinos de Cobre , Masculino , Feminino , Humanos , Levanogestrel , Acetato de Medroxiprogesterona , Sexo sem Proteção , Antígeno Prostático Específico , Distribuição Aleatória , Infecções por HIV/diagnóstico , África do Sul
18.
Phys Chem Chem Phys ; 25(19): 13728-13740, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37158387

RESUMO

The electrochemical hydrogen evolution reaction (HER) in alkaline media provides an environmentally friendly industrial application approach to replace traditional fossil energy. The search for efficient, low-cost, and durable active electrocatalysts is central to the development of this area. Transition metal carbides (MXenes) have been emerging as a new family of two-dimensional (2D) materials that have great potential in the HER. Herein, density functional theory calculations are performed to systematically explore the structural and electronic properties and alkaline HER performances of Mo-based MXenes, as well as the influence of species and the coordination environment of single atoms on the improvement of the electrocatalytic activity of Mo2Ti2C3O2. The results show that Mo-based MXenes (Mo2CO2, Mo2TiC2O2, and Mo2Ti2C3O2) exhibit excellent H binding ability, while slow water decomposition kinetics hinders their HER performance. Replacing the O-terminal of Mo2Ti2C3O2 with a Ru single-atom (RuS-Mo2Ti2C3O2) could promote the decomposition of water owing to the stronger electron-donating ability of the atomic state Ru. In addition, Ru could also improve the binding ability of the catalyst to H by adjusting the surface electron distribution. As a result, RuS-Mo2Ti2C3O2 exhibits excellent HER performance with a water decomposition potential barrier of 0.292 eV and a H adsorption Gibbs free energy of -0.041 eV. These explorations bring new prospects for single atoms supported on Mo-based MXenes in the alkaline hydrogen evolution reaction.

19.
BMC Cardiovasc Disord ; 23(1): 284, 2023 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-37270600

RESUMO

OBJECTIVE: To investigate the possible association between AT1R gene polymorphisms and major adverse cardiovascular and cerebrovascular events (MACCEs) in hypertension patients combined with or without coronary artery disease (CAD) in Xinjiang. METHODS: 374 CAD patients and 341 non-CAD individuals were enrolled as study participants and all of them have a hypertension diagnosis. AT1R gene polymorphisms were genotyped by SNPscan™ typing assays. During the follow-up in the clinic or by telephone interview, MACCEs were recorded. Kaplan-Meier curves and Cox survival analyses were used to explore the association between AT1R gene polymorphisms and the occurrence of MACCEs. RESULTS: AT1R gene rs389566 was associated with MACCEs. The TT genotype of the AT1R gene rs389566 had a significantly higher probability of MACCEs than the AA + AT genotype (75.2% vs. 24.8%, P = 0.033). Older age (OR = 1.028, 95% CI: 1.009-1.0047, P = 0.003) and TT genotype of rs389566 (OR = 1.770, 95% CI: 1.148-2.729, P = 0.01) were risk factors of MACCEs. AT1R gene rs389566 TT genotype may be a predisposing factor for the occurrence of MACCEs in hypertensive patients. CONCLUSION: We should also pay more attention to the prevent of MACCEs in hypertension patients combined with CAD. Especially those elderly hypertensive patients carrying AT1R rs389566 TT genotype requires avoidance of unhealthy lifestyle, better management of blood pressure control and reduce the occurrence of MACCEs.


Assuntos
Doença da Artéria Coronariana , Hipertensão , Receptor Tipo 1 de Angiotensina , Idoso , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/genética , Genótipo , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipertensão/genética , Polimorfismo Genético , Receptor Tipo 1 de Angiotensina/genética , Fatores de Risco
20.
Sensors (Basel) ; 23(4)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36850670

RESUMO

We designed a tunable diode laser absorption spectroscopy (TDLAS) sensor for the online monitoring of CO2 and H2O concentrations. It comprised a small self-design multi-pass cell, home-made laser drive circuits, and a data acquisition circuit. The optical and electrical parts and the gas circuit were integrated into a portable carrying case (height = 134 mm, length = 388 mm, and width = 290 mm). A TDLAS drive module (size: 90 mm × 45 mm) was designed to realize the function of laser current and temperature control with a temperature control accuracy of ±1.4 mK and a current control accuracy of ±0.5 µA, and signal acquisition and demodulation. The weight and power consumption of the TDLAS system were only 5 kg and 10 W, respectively. Distributed feedback lasers (2004 nm and 1392 nm) were employed to target CO2 and H2O absorption lines, respectively. According to Allan analysis, the detection limits of CO2 and H2O were 0.13 ppm and 3.7 ppm at an average time of 18 s and 35 s, respectively. The system response time was approximately 10 s. Sensor performance was verified by measuring atmospheric CO2 and H2O concentrations for 240 h. Experimental results were compared with those obtained using a commercial instrument LI-7500, which uses non-dispersive infrared technology. Measurements of the developed gas analyzer were in good agreement with those of the commercial instrument, and its accuracy was comparable. Therefore, the TDLAS sensor has strong application prospects in atmospheric CO2 and H2O concentration detection and ecological soil flux monitoring.

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