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1.
Health Place ; 87: 103236, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38593578

RESUMO

BACKGROUND: Although exposure to greenness has generally benefited human metabolic health, the association between greenness exposure and metabolic obesity remains poorly studied. We aimed to investigate the associations between residential greenness and obesity phenotypes and the mediation effects of air pollutants and physical activity (PA) level on the associations. METHODS: We used the baseline of the China Multi-Ethnic Cohort (CMEC) study, which enrolled 87,613 adults. Obesity phenotypes were defined based on obesity and metabolic status, including metabolically unhealthy obesity (MUO), non-obesity (MUNO), metabolically healthy obesity (MHO), and non-obesity (MHNO). Greenness exposure was measured as the 3-year mean values of the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) within the 500-m buffer zones around the participants' residence. Multivariable logistic regression was used to estimate the associations between greenness and obesity phenotypes. Stratified analyses by age, sex, educational level, and urbanicity were performed to identify how the effect varies across different subgroups. Causal mediation analysis was used to examine the mediation effects of air pollutants and PA level. RESULTS: Compared with MHNO, each interquartile range (IQR) increase in greenness exposure was associated with reduced risks of MHO (ORNDVI [95% CI] = 0.87 [0.81, 0.93]; OREVI = 0.91 [0.86, 0.97]), MUO (ORNDVI = 0.83 [0.78, 0.88]; OREVI = 0.86 [0.81, 0.91]), and MUNO (ORNDVI = 0.88 [0.84, 0.91]; OREVI = 0.89 [0.86, 0.92]). For each IQR increase in both NDVI and EVI, the risks of MHO, MUO, and MUNO were reduced more in men, participants over 60 years, those with a higher level of education, and those living in urban areas, compared to their counterparts. Concentrations of particulate matter (PM) and PA level partially mediated the associations between greenness exposure and obesity phenotypes. CONCLUSIONS: Exposure to residential greenness was associated with decreased risks of MHO, MUO, and MUNO, which was mediated by concentrations of PM and PA level, and modified by sex, age, educational level, and urbanicity.


Assuntos
Obesidade , Fenótipo , Humanos , Masculino , China/epidemiologia , Feminino , Obesidade/epidemiologia , Pessoa de Meia-Idade , Adulto , Características de Residência/estatística & dados numéricos , Exercício Físico , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Idoso , Meio Ambiente , Estudos de Coortes , Exposição Ambiental/efeitos adversos , Poluição do Ar/efeitos adversos
2.
Herz ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658408

RESUMO

OBJECTIVE: Many previous studies reported the relationship between lipoprotein(a) and cardiovascular disease, but the conclusions were controversial. The aim of our study was to retrospectively investigate the association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography. METHODS: We collected and compared clinical information of patients hospitalized for coronary angiography. Multivariable hierarchical logistic regression was used to evaluate the association between lipoprotein(a) and cardiovascular disease in patients undergoing coronary angiography. RESULTS: There were no significant differences in gender, hypertension, APOA1, smoking, hyperuricemia, obesity, acute myocardial infarction (AMI), cardiac insufficiency, family history of diabetes, or family history of hyperlipidemia among the four groups of lipoprotein(a). Elevated lipoprotein(a) does not increase the risk of hypertriglyceridemia, while elevated lipoprotein(a) increases the risk of high total cholesterol and high low-density lipoprotein cholesterol (LDL-c). Elevated lipoprotein(a) increases the risk of diabetes and premature coronary artery disease (CAD). Elevated lipoprotein(a) increases the incidence of CAD, multivessel lesions, and percutaneous coronary intervention (PCI). Multivariate logistic regression analysis further showed that elevated lipoprotein(a) increases the incidence of high total cholesterol, high LDL­c, diabetes, CAD, premature CAD, multivessel lesions, and PCI. CONCLUSION: The findings indicated that elevated lipoprotein(a) had no obvious relationship with hypertension and obesity. Elevated lipoprotein(a) increases the risk of high total cholesterol, high LDL­c, and premature CAD, and increases the occurrence and severity of coronary heart disease.

3.
Nanomaterials (Basel) ; 14(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38607169

RESUMO

Amorphous alloys or metallic glasses (MGs) thin films have attracted extensive attention in various fields due to their unique functional properties. Here, we use in situ heating transmission electron microscopy (TEM) to investigate the thermal stability and crystallization behavior of Pd-Au-Si thin films prepared by a pulsed laser deposition (PLD) method. Upon heating treatment inside a TEM, we trace the structural changes in the Pd-Au-Si thin films through directly recording high-resolution images and diffraction patterns at different temperatures. TEM observations reveal that the Pd-Au-Si thin films started to nucleate with small crystalline embryos uniformly distributed in the glassy matrix upon approaching the glass transition temperature Tg=625K, and subsequently, the growth of crystalline nuclei into sub-10 nm Pd-Si nanocrystals commenced. Upon further increasing the temperature to 673K, the thin films transformed to micro-sized patches of stacking-faulty lamellae that further crystallized into Pd9Si2 and Pd3Si intermetallic compounds. Interestingly, with prolonged thermal heating at elevated temperatures, the Pd9Si2 transformed to Pd3Si. Simultaneously, the solute Au atoms initially dissolved in glassy alloys and eventually precipitated out of the Pd9Si2 and Pd3Si intermetallics, forming nearly spherical Au nanocrystals. Our TEM results reveal the unique thermal stability and crystallization processes of the PLD-prepared Pd-Au-Si thin films as well as demonstrate a possibility of producing a large quantity of pure nanocrystals out of amorphous solids for various applications.

4.
BMC Public Health ; 24(1): 32, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166669

RESUMO

BACKGROUND: Healthy lifestyles are crucial for preventing chronic diseases. Nonetheless, approximately 90% of Chinese community residents regularly engage in at least one unhealthy lifestyle. Mobile smart devices-based health interventions (mHealth) that incorporate theoretical frameworks regarding behavioral change in interaction with the environment may provide an appealing and cost-effective approach for promoting sustainable adaptations of healthier lifestyles. We designed a randomized controlled trial (RCT) to evaluate the effectiveness of a socioecological model-guided, smart device-based, and self-management-oriented lifestyles (3SLIFE) intervention, to promote healthy lifestyles among Chinese community residents. METHODS: This two-arm, parallel, cluster-RCT with a 6-month intervention and 6-month follow-up period foresees to randomize a total of 20 communities/villages from 4 townships in a 1:1 ratio to either intervention or control. Within these communities, a total of at least 256 community residents will be enrolled. The experimental group will receive a multi-level intervention based on the socioecological model supplemented with a multi-dimensional empowerment approach. The control group will receive information only. The primary outcome is the reduction of modifiable unhealthy lifestyles at six months, including smoking, excess alcohol consumption, physical inactivity, unbalanced diet, and overweight/obesity. A reduction by one unhealthy behavior measured with the Healthy Lifestyle Index Score (HLIS) will be considered favorable. Secondary outcomes include reduction of specific unhealthy lifestyles at 3 months, 9 months, and 12 months, and mental health outcomes such as depression measured with PHQ-9, social outcomes such as social support measured with the modified Multidimensional Scale of Perceived Social Support, clinical outcomes such as obesity, and biomedical outcomes such as the development of gut microbiota. Data will be analyzed with mixed effects generalized linear models with family and link function determined by outcome distribution and accounting for clustering of participants in communities. DISCUSSION: This study will provide evidence concerning the effect of a mHealth intervention that incorporates a behavioral change theoretical framework on cultivating and maintaining healthy lifestyles in community residents. The study will provide insights into research on and application of similar mHealth intervention strategies to promote healthy lifestyles in community populations and settings. TRIAL REGISTRATION NUMBER: ChiCTR2300070575. Date of registration: April 17, 2023. https://www.chictr.org.cn/index.aspx .


Assuntos
Autogestão , Humanos , Exercício Físico , Estilo de Vida , Obesidade , Estilo de Vida Saudável , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Dement Geriatr Cogn Disord ; 53(1): 19-28, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38232713

RESUMO

INTRODUCTION: Mental health symptoms and cognitive impairment are highly prevalent and intertwined among aging people living with HIV (PLWH). This study aimed to assess the interrelationships and strength of connections between individual mental health symptoms and cognitive impairment. We sought to identify specific symptoms linking mental health and cognitive impairment in aging PLWH. METHODS: Participants in the Sichuan Older People with HIV Infections Cohort Study (SOHICS) were recruited between November 2018 and April 2021 in China. Mental health symptoms, including depression and anxiety, were assessed by the Patient Health Questionnaire (PHQ-9) and General Anxiety Disorder-7 (GAD-7), respectively. Cognitive impairment was assessed by the Montreal Cognitive Assessment-Basic (MoCA-B). Partial correlation networks were used to depict the interrelationships between mental health symptoms and cognitive impairment, and bridge strength was used to identify specific symptoms linking mental health and cognitive impairment. RESULTS: Of the 1,587 recruited participants with a mean age of 63.0 years old, 47.0% had mild or severe cognitive impairment. Network analysis revealed that cognitive function, visual perception, and problem-solving task of the MoCA-B were negatively correlated with appetite, energy, and motor of the PHQ-9, respectively. Based on their interrelationships, problem-solving task and motor acted as bridge symptoms. CONCLUSION: Problem-solving task and motor may be potential intervention targets to reduce the overall risk of mental health symptoms and cognitive impairment. Future research could assess the feasibility and effectiveness of specific interventions designed for the two symptoms of aging PLWH.


Assuntos
Transtornos de Ansiedade , Disfunção Cognitiva , Infecções por HIV , Humanos , Idoso , Infecções por HIV/complicações , Infecções por HIV/psicologia , Saúde Mental , Estudos de Coortes , Envelhecimento , China/epidemiologia
6.
J Psychosom Res ; 177: 111565, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38128387

RESUMO

OBJECTIVES: Old people living with HIV (PLWH) are highly susceptible to HIV-related psychological and neurocognitive disorders, which are multidimensional and inseparably intertwined. Despite this, few studies have investigated the interrelationship between these disorders. We aimed to estimate the detailed associations and identify potential intervention points between HIV-related psychological factors and cognitive function in old PLWH. METHODS: This cross-sectional study drew on the Older People with HIV Infections Cohort from 65 communities in Sichuan, China. Three HIV-related psychological factors, including illness perception, HIV stigma perception and resilience, were collected using a self-reported questionnaire. Cognitive function was measured using the MoCA-B scale. Network analysis was used to estimate the interrelationships between HIV-related psychological factors and cognitive function dimensions in old PLWH, and to identify factors that act as bridges in connecting these factors in the network. RESULTS: Of the 1587 old PLWH, 47.0% had mild or severe cognitive function impairment. Network analysis revealed that better visual perception was directly connected with poorer negative self-image (edge weight: 0.13), and poorer illness comprehensibility was connected with poor visual perception (-0.09) and executive functioning (-0.13). The cognitive illness perceptions (bridge strength: 0.41), illness comprehensibility (0.36) and negative self-image (0.39) were identified as bridges connecting HIV-related psychological and cognitive function. CONCLUSIONS: The interconnection of HIV-related illness perception, stigma perception, and resilience with cognition may be achieved through the links of negative self-image, illness comprehensibility and cognitive illness perceptions. These factors may serve as potential non-pharmaceutical action points to improve psychological and cognitive health among old PLWH.


Assuntos
Infecções por HIV , Resiliência Psicológica , Humanos , Idoso , Infecções por HIV/complicações , Infecções por HIV/psicologia , Estudos Transversais , Estigma Social , Cognição , Inquéritos e Questionários , Percepção
7.
Prev Med ; 177: 107780, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37967619

RESUMO

Inconsistent correlations of screen use with physical activity (PA) and social capital (SC) in youths have been observed in existing cross-sectional studies. This study aimed to elucidate associations among variables in screen use, PA, and SC domains during COVID-19, to improve the prediction and prevention of suboptimal health status in youths. An online survey based on the nationwide COVID-19 Impact on Lifestyle Change Survey (COINLICS) was conducted in China, and 10,082 youths reported their screen use, PA, and SC in the months immediately before, during, and after the COVID-19 lockdown. Cross-sectional and longitudinal network models were used to identify associations of variables in domains of screen use with PA and SC. Effect modifications of bridges and predictors in the associations were examined. The network models suggested that individual SC was a bridge that strongly connected other types of SC, and domains of screen use and PA before lockdown, while phone use became such a bridge during and after lockdown. More PC/TV use before lockdown predicted less household-related PA during lockdown (ß = -0.142); more phone use during lockdown was a predictor for higher levels of household-related PA (ß = 0.106), active transport (ß = 0.096), and individual SC (ß = 0.072) after lockdown. Phone use was negatively associated with PA through PC/TV use in the more phone use subgroup. Relationships among screen use, PA, and SC dynamically changed during COVID-19, and phone use that was identified as a bridge and a predictor may be the potential action point for health intervention in youths during lockdown.


Assuntos
COVID-19 , Capital Social , Humanos , Adolescente , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Estudos Transversais , Pandemias/prevenção & controle , China/epidemiologia , Exercício Físico
8.
Front Microbiol ; 14: 1251211, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37779709

RESUMO

Chryseobacterium indologenes is one of the primary causative agents of root rot of Panax notoginseng, which significantly affected plant growth and caused economic losses. With the increasing incidence of antibiotic-resistant bacterial phytopathogens, phage therapy has been garnered renewed attention in treating pathogenic bacteria. However, the therapeutic potential of phage therapy on root rot of P. notoginseng has not been evaluated. In this study, we isolated a novel lytic phage MA9V-1 infecting C. indologenes MA9 from sewage and monitored the formation of clear and round plaques with a diameter of approximately 0.5-1.5 mm. Phage MA9V-1 exhibited rapid absorption (>75% in 8 min), a latency period of 20 min, and a burst size of 10 particles per cell. Transmission electron microscopy indicated that the phage MA9V-1 is a new myovirus hosting C. indologenes MA9. Sequencing of phage genomes revealed that phage MA9V-1 contained a linear double-stranded DNA genome of 213,507 bp with 263 predicted open reading frames, including phage structure, host lysing, and DNA polymerase/helicase but no genes of tRNA, virulence, and antibiotic resistance. Our proteomic tree and genomic analysis revealed that phage MA9V-1 shares identity with Sphingomonas phage PAU and Tenacibaculum phage PTm1; however, they also showed apparent differences. Further systemic evaluation using phage therapy experiments on P. notoginseng suggested that phage MA9V-1 can be a potential candidate for effectively controlling C. indologenes MA9 infection. Thus, we have presented a novel approach to solving root rot in P. notoginseng.

9.
Afr J Reprod Health ; 27(5): 95-104, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37584934

RESUMO

Extremely low-frequency electromagnetic radiation (ELF-EMF) are generated by electrical devices and power systems (1 to 300 Hz). Although several studies have demonstrated that ELF-EMF may beassociated with an increased risk of adverse pregnancy outcomes, other studies have shown no evidence of associations. This meta-analysis was conducted to assess the effect of extremely low frequency electromagnetic radiation on pregnancy outcomes. The following electronic bibliographic databases were searched to identify relevant studies: PubMed, Web Of Science, Cochrane library, Embase, EBSCO. In addition, the manual retrieval of relevant references was conducted as a supplement. Select all eligible studies published from Database construction library to March 10, 2021. Search type for queue research on influence of electromagnetic field radiation on pregnancy results. Data were screened and extracted independently by two researchers. Review Manager 5.3 software was used for the meta-analysis. There was no significant increase in the risk of miscarriage, stillbirth, birth defects and preterm delivery in the pregnant women who lived near the electromagnetic fields compared with the control group. Conclusions: No correlation has been found between maternal ELF-EMF exposure and miscarriage, stillbirth, neonatal birth defects and preterm delivery, while the effects on small gestational age and low birth weight are still uncertain. Related research with high-quality large samples and different regions are still needed for further verification.


Assuntos
Aborto Espontâneo , Nascimento Prematuro , Recém-Nascido , Gravidez , Humanos , Feminino , Natimorto/epidemiologia , Resultado da Gravidez/epidemiologia , Radiação Eletromagnética
10.
Clin Exp Hypertens ; 45(1): 2233717, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37454306

RESUMO

BACKGROUND: Anthocyanin plays a protective role in cardiovascular disease through antioxidant effect. Whether anthocyanin can reduce salt-induced hypertension and the related mechanisms remain unclear. METHODS: Chronic infusion of vehicle (artificial cerebrospinal fluid, aCSF, 0.4 µL/h) or anthocyanin (10 mg/kg, 0.4 µL/h) into bilateral paraventricular nucleus (PVN) of Sprague-Dawley rats was performed. Then, the rats were fed a high salt diet (8% NaCl, HS) or normal salt diet (0.9%, NaCl, NS) for 4 weeks. RESULTS: High salt diet induced an increase in blood pressure and peripheral sympathetic nerve activity (increased LF/HF and decreased SDNN and RMSSD), which was accompanied by increased reactive oxygen species (ROS) production and angiotensin II type-1 receptor (AT1R) expression and function in the PVN. Moreover, the NOD-like receptor protein 3 (NLRP3) and related inflammatory proteins (caspase-1) expression, the pro-inflammatory cytokine levels including IL-1ß and TNF-α were higher in PVN of rats with a high salt diet. Bilateral PVN infusion of anthocyanin attenuated NLRP3-dependent inflammation (NLRP3, caspase-1, IL-1ß and TNF-α) and ROS production, reduced AT1R expression and function in PVN and lowered peripheral sympathetic nerve activity and blood pressure in rats with salt-induced hypertension. CONCLUSIONS: Excessive salt intake activates NLRP3-dependent inflammation and oxidative stress and increased AT1R expression and function in the PVN. Bilateral PVN infusion of anthocyanin lowers peripheral sympathetic nerve activity and blood pressure in rats with salt-induced hypertension by improvement of expression and function of AT1R in the PVN through inhibiting NLRP3 related inflammatory and oxidative stress.


Assuntos
Antocianinas , Hipertensão , Ratos , Animais , Antocianinas/efeitos adversos , Antocianinas/metabolismo , Cloreto de Sódio na Dieta/efeitos adversos , Espécies Reativas de Oxigênio/metabolismo , Cloreto de Sódio/efeitos adversos , Cloreto de Sódio/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ratos Sprague-Dawley , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Sistema Nervoso Simpático , Inflamação/metabolismo , Caspases/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo
11.
Phys Chem Chem Phys ; 25(25): 16962-16967, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37334887

RESUMO

Monolayer (ML) NiCl2 exhibits a strong biquadratic exchange interaction between the first neighboring magnetic atoms (B1), as demonstrated by the spin spiral model in J. Ni et al., Phys. Rev. Lett., 2021, 127, 247204. This interaction is crucial for stabilizing the ferromagnetic collinear order within the ML NiCl2. However, they neither point out the role of B1 nor discuss the dispersion relation from spin orbit coupling (SOC) in the spin spiral. As we have done in this work, these parameters might theoretically potentially be derived directly by fitting the calculated spin spiral dispersion relation. Here, we draw attention to the fact that B1 is equivalent to half of J3 in Heisenberg linear interactions and that the positive B1 partially counteracts the negative J3's impact on the spin spiral to make the ML NiCl2 ferromagnetic. The comparatively small J3 + 1/2B1 from the spin spiral led us to believe that J3 could be substituted by B1, yet it still exists and plays a crucial function in magnetic semiconductors or insulators. The dispersion relation, which we also obtain from SOC, displays weak antiferromagnetic behavior in the spin spiral.

12.
Phys Rev Lett ; 130(19): 196801, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37243636

RESUMO

The switchable electric polarization is usually achieved in ferroelectric materials with noncentrosymmetric structures, which opens exciting opportunities for information storage and neuromorphic computing. In another polar system of p-n junction, there exists the electric polarization at the interface due to the Fermi level misalignment. However, the resultant built-in electric field is unavailable to manipulate, thus attracting less attention for memory devices. Here, we report the interfacial polarization hysteresis (IPH) in the vertical sidewall van der Waals heterojunctions of black phosphorus and quasi-two-dimensional electron gas on SrTiO_{3}. A nonvolatile switching of electric polarization can be achieved by reconstructing the space charge region (SCR) with long-lifetime nonequilibrium carriers. The resulting electric-field controllable IPH is experimentally verified by electric hysteresis, polarization oscillation, and pyroelectric effect. Further studies confirm the transition temperature of 340 K, beyond which the IPH vanishes. The second transition is revealed with the temperature dropping below 230 K, corresponding to the sharp improvement of IPH and the freezing of SCR reconstruction. This work offers new possibilities for exploring the memory phenomena in nonferroelectric p-n heterojunctions.

13.
Phys Chem Chem Phys ; 25(22): 15469-15478, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37249388

RESUMO

Two-dimensional magnetic materials with tunable electronic properties have great potential application in spintronic devices. Here, based on first-principles calculations, we systematically study the electronic structures and magnetic properties of monolayer NiMnBr6. The magnetic ground state of monolayer NiMnBr6 is Néel ferrimagnetic (FIM-Néel) with a critical temperature (Tc) of 45 K. The magnetic properties of monolayer NiMnBr6 can be tuned effectively by strain. The magnetic phase transition from the FIM-Néel state to the ferromagnetic (FM) state can be triggered by applying a compressive strain greater than 4.5%. The Tc of the FIM-Néel state and FM state can be increased to 67 K and 95 K by applying 8.0% tensile and compressive strain, respectively. Monolayer NiMnBr6 in both the FIM-Néel state and FM state has large magnetic anisotropy energy. Remarkably, the monolayer NiMnBr6 in the FIM-Néel state acts as a bipolar ferrimagnetic semiconductor (BFIMS), while the compressive strained monolayer NiMnBr6 in the FM state acts as a half FM semiconductor (HFMS). The magnetic configuration of monolayer NiMnBr6 can also be tuned by carrier doping. Interestingly, for monolayer NiMnBr6 with the HFMS phase, the magnetic phase transition from the FM state to FIM-Néel state can be achieved with the increase of the hole doping concentration, which leads to the achievement of a doping concentration induced carrier spin flip. Our results show that monolayer NiMnBr6 is a promising candidate for exploring two-dimensional magnetism and spintronic devices.

14.
Nanomaterials (Basel) ; 13(3)2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-36770495

RESUMO

The doping of impurity ions into perovskite lattices has been scrupulously developed as a promising method to stabilize the crystallographic structure and modulate the optoelectronic properties. However, the photoluminescence (PL) of Fe2+-doped mixed halide perovskite NCs is still relatively unexplored. In this work, the Fe2+-doped CsPb(ClxBr1-x)3 nanocrystals (NCs) are prepared by a hot injection method. In addition, their optical absorption, photoluminescence (PL), PL lifetimes, and photostabilities are compared with those of undoped CsPb(Br1-xClx)3 NCs. We find the Fe2+ doping results in the redshift of the absorption edge and PL. Moreover, the full width at half maximums (FWHMs) are decreased, PL quantum yields (QYs) are improved, and PL lifetimes are extended, suggesting the defect density is reduced by the Fe2+ doping. Moreover, the photostability is significantly improved after the Fe2+ doping. Therefore, this work reveals that Fe2+ doping is a very promising approach to modulate the optical properties of mixed halide perovskite NCs.

15.
Phys Chem Chem Phys ; 25(8): 6537-6544, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36786679

RESUMO

Two-dimensional (2D) materials are an excellent platform for surface-enhanced Raman spectroscopy (SERS). However, a poor detection sensitivity hinders their practical application. Exciton resonance (µex) can improve SERS significantly by lending intensity to nearby charge-transfer resonance. Coincidentally, for ReS2, the enhanced µex can be achieved through the injection of excited-state electrons which can adjust the energy band to the SERS detection range. Moreover, ReS2 has strong anisotropic properties, which adds an additional dimension for SERS. Therefore, ReS2 is an ideal candidate to realize highly sensitive anisotropic SERS. In this paper, the metallic T phase of ReS2 is introduced to the semiconducting Td phase by phase engineering. The photoinduced electron tunneling from the T phase to the Td phase can tune exciton emissions to the visible region, which effectively facilitates the photoinduced charge transfer processes. With RhB as the probe molecule, the synergistic resonance effects improve the limit of detection to 10-9 M with the enhancement factor up to about 108. Meanwhile, the obtained ultrasensitive SERS substrates also show good uniformity, stability as well as unique anisotropy. Our results open a new perspective in the improvement of the SERS performance.

16.
Chest ; 163(1): 100-114, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35921883

RESUMO

BACKGROUND: Inhaled corticosteroids (ICSs) have been used widely in the maintenance therapy of COPD. However, whether inhaled therapy containing ICSs can reduce the all-cause mortality risk and the possible benefited patient subgroups is unclear. RESEARCH QUESTION: Does inhaled therapy containing ICSs reduce the all-cause mortality risk in patients with COPD compared with other inhaled therapies not containing ICSs? STUDY DESIGN AND METHODS: We searched PubMed, Cochrane Library, Embase, and ClinicalTrials.gov for relevant randomized clinical trials (RCTs). Pooled results were calculated using Peto ORs with corresponding 95% CIs. RESULTS: Sixty RCTs enrolling 103,034 patients were analyzed. Inhaled therapy containing ICSs (Peto OR, 0.90; 95% CI, 0.84-0.97), especially triple therapy (Peto OR, 0.73; 95% CI, 0.59-0.91), was associated with a reduction in the all-cause mortality risk among patients with COPD when compared with inhaled therapy without ICSs. Subgroup analyses revealed that treatment duration of > 6 months (Peto OR, 0.90; 95% CI, 0.83-0.97), medium-dose ICSs (Peto OR, 0.71; 95% CI, 0.56-0.91), low-dose ICSs (Peto OR, 0.88; 95% CI, 0.79-0.97), and budesonide (Peto OR, 0.75; 95% CI, 0.59-0.94) were involved in this association. The predictors of this association included eosinophil counts of ≥ 200/µL or percentage of ≥ 2%, documented history of ≥ 2 moderate and severe exacerbations in the previous year, Global Initiative for Chronic Obstructive Lung Disease stages III or IV, age younger than 65 years, and BMI of ≥ 25 kg/m2, among which eosinophil counts of ≥ 200/µL (Peto OR, 0.58; 95% CI, 0.36-0.95) were the strongest predictor. INTERPRETATION: Inhaled therapy containing ICSs, especially triple therapy, of longer than 6 months was associated with a reduction in the all-cause mortality risk in patients with COPD. The predictors of this association included medication factors and patient characteristics, among which eosinophil counts of ≥ 200/µL were the strongest predictor. TRIAL REGISTRY: PROSPERO; No.: CRD42022304725; URL: https://www.crd.york.ac.uk/prospero/.


Assuntos
Corticosteroides , Doença Pulmonar Obstrutiva Crônica , Humanos , Idoso , Ensaios Clínicos Controlados Aleatórios como Assunto , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Budesonida/uso terapêutico , Administração por Inalação
17.
J Biotechnol ; 359: 65-74, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36184003

RESUMO

Heavy metal contamination is a global issue, with cadmium (Cd2+) and its treatment becoming major environmental challenge that could be solved by microbial restoration, an eco-friendly technique. Serratia marcescens KMR-3 exhibits high tolerance and removal rate of Cd2+ (≤500 mg/L). Here, we aimed to explore mechanisms underlying tolerance to and removal of Cd2+ by KMR-3. Scanning electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectrometry were conducted to analyze characteristics of the KMR-3 biofilm and Cd2+ combined forms. The results revealed varying degrees of cell adhesion, membrane thickening, and shrinkage on the surface of the bacteria. The binding elements, electronic binding energy, and functional groups on the surface of the bacteria exhibited changes. Furthermore, the biofilm amount following treatment with Cd2+ was 1.5-3 times higher than that in the controls, treatment with Cd2+ substantially enhanced biofilm generation and increased Cd2+ adsorption. Cd2+ adsorption by its own secondary metabolite prodigiosin produced by KMR-3 was enhanced by 19.5 % compared with that observed without prodigiosin. Through transcriptome sequencing and RT-qPCR, we observed that Znu protein-chelating system regulated gene expression (znuA, znuB, and znuC), and the efflux mechanism of the P-type ATPase regulated the expression of genes (zntA, zntB, and zntR), which were significantly enhanced. Through the combined action of various strategies, KMR-3 demonstrated a high tolerance and removal ability of Cd2+, providing a theoretical basis to treat Cd2+ pollution.


Assuntos
Metais Pesados , ATPases do Tipo-P , Serratia marcescens/genética , Serratia marcescens/química , Serratia marcescens/metabolismo , Prodigiosina/metabolismo , Cádmio , Metais Pesados/metabolismo , ATPases do Tipo-P/metabolismo
18.
J Inorg Biochem ; 236: 111978, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36063739

RESUMO

Prodigiosin (2-methyl-3-pentyl-6-methoxyprodiginine), a red-colored microbial pigment, is produced in large quantities by Serratia marcescens KMR-3. This bacterium can grow in a medium with a Cd2+ concentration of 500 mg/L, but it does not produce prodigiosin when the Cd2+ concentration in the medium is higher than 140 mg/L. Therefore, we investigated the mechanisms by which Cd2+ inhibits prodigiosin synthesis. Upon addition of Cd2+ to the medium, the expression of the prodigiosin (pig) gene cluster was significantly downregulated. Simultaneously, genes encoding proteins related to the synthesis of arginine and proline(prodigiosin precursors) were significantly downregulated, while the degradation-related genes were upregulated. Furthermore, PigF, which encodes a key enzyme involved in the synthesis of 4-methoxy-2,2'-bipyrrole-5-carboxaldehyde and PigC, which encodes a key enzyme involved in the last step of prodigiosin synthesis, were downregulated by 80% and 55%, respectively, following Cd2+ treatment. As PigC and PigF are located on the cell membrane and are involved in the final steps of prodigiosin synthesis, the cell membrane might be presumed to be the site of prodigiosin synthesis. The bacterial membrane exhibited different degrees of elongation, folding, fragmentation, and sagging after the addition of Cd2+, while likely destroying the site of prodigiosin synthesis.


Assuntos
Prodigiosina , Serratia marcescens , Animais , Arginina/metabolismo , Cádmio/metabolismo , Feminino , Fator de Crescimento Placentário/metabolismo , Prodigiosina/metabolismo , Prolina , Serratia marcescens/genética , Serratia marcescens/metabolismo
19.
ACS Appl Mater Interfaces ; 14(39): 44676-44684, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-36128726

RESUMO

In organic resistive random-access memory (ReRAM) devices, deeply understanding how to control the performance of π-conjugated semiconductors through molecular-shape-engineering is important and highly desirable. Herein, we design a family of N-containing heteroaromatic semiconductors with molecular shapes moving from mono-branched 1Q to di-branched 2Q and tri-branched 3Q. We find that this molecular-shape engineering can induce reliable binary to ternary ReRAM switching, affording a highly enhanced device yield that satisfies the practical requirement. The density functional theory calculation and experimental evidence suggest that the increased multiple paired electroactive nitrogen sites from mono-branched 1Q to tri-branched 3Q are responsible for the multilevel resistance switching, offering stable bidentate coordination with the active metal atoms. This study sheds light on the prospect of N-containing heteroaromatic semiconductors for promising ultrahigh-density data-storage ReRAM application.

20.
iScience ; 25(4): 104039, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35330683

RESUMO

Based on density functional theory calculations, we elucidated the tunability of the atomic structures and magnetic interactions of Co/Pt3 interface (one layer of hcp(0001) Co and three layers of fcc(111) Pt) and thus the skyrmion sizes using strain. The dispersion relations of the spin spiral in the opposite directions, E(q) and E(-q), were evaluated based on generalized Bloch equations. Effective exchange coupling (EC) and Dzyaloshinsky-Moriya interaction (DMI) parameters between different neighbors J i and d i at different lattice constants were derived by fitting the resulting spin spiral dispersion E(q) to EC model with DMI and E(q)-E(-q) formula, respectively. We observed an increase in DMI and a significant decrease in EC with an increase in strain. Hence, the size of Néel-type skyrmions determined by the ratio of EC/DMI can be controlled by applying strain, leading to an effective approach to tailor the formation of skyrmion lattices by inducing slight structural modifications on the magnetic thin films.

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