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1.
Artigo em Inglês | MEDLINE | ID: mdl-38723155

RESUMO

Lead and its compounds can have cumulative harmful effects on the nervous, cardiovascular, and other systems, and especially affect the brain development of children. We collected 4918 samples from 15 food categories in 11 districts of Guangzhou, China, from 2017 to 2022, to investigate the extent of lead contamination in commercial foods and assess the health risk from dietary lead intake of the residents. Lead was measured in the samples using inductively coupled plasma mass spectrometry. Dietary exposure to lead was calculated based on the food consumption survey of Guangzhou residents in 2011, and the health risk of the population was evaluated using the margin of exposure (MOE) method. Lead was detected in 76.5% of the overall samples, with an average lead content of 29.4 µg kg-1. The highest lead level was found in bivalves. The mean daily dietary lead intakes were as follows: 0.44, 0.34, 0.25, and 0.28 µg kg-1 body weight (bw) day-1 for groups aged 3-6, 7-17, 18-59, and ≥ 60 years, respectively. Rice and rice products, leafy vegetables, and wheat flour and wheat products were identified as the primary sources of dietary lead exposure, accounting for 73.1%. The MOE values demonstrated the following tendency: younger age groups had lower MOEs, and 95% confidence ranges for the groups aged 3-6 and 7-17 began at 0.6 and 0.7, respectively, indicating the potential health risk of children, while those for other age groups were all above 1.0. Continued efforts are needed to reduce dietary lead exposure in Guangzhou.

2.
J Affect Disord ; 358: 391-398, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38735577

RESUMO

BACKGROUND: Personality traits, especially neuroticism, can influence susceptibility to dementia. Social contact mitigates stress and risk of dementia, the extent to which social contact can mitigate excess risk associated with neuroticism remains unclear. We aim to investigate whether active social contact is associated with lower neuroticism-associated excess risk of dementia. METHODS: This prospective cohort study examined 393,939 UK Biobank participants (mean [SD] age: 56.4 [8.1] years; 53.7 % female) assessed from 2006 to 2010 and followed up until December 2022. Neuroticism was measured using the Revised Eysenck Personality Questionnaire. Social contact levels were assessed based on household size, contact with family or friends, and group participation. Dementia was determined using linked electronic health records. RESULTS: High neuroticism was associated with increased all-cause dementia risk and cause-specific dementia. Among high neuroticism participants, excess risk of all-cause dementia showed a stepwise decrease with increasing social contact (low: hazard ratios (HR) = 1.27, 95 % confidence interval (CI) = 1.15-1.40; intermediate: HR = 1.20, 95 % CI = 1.12-1.28; high: HR = 1.07, 95 % CI = 1.00-1.15). High social contact similarly decreased excess risk of cause-specific dementia, comparable to those with low neuroticism. LIMITATIONS: Neuroticism and social contact information relied on self-report questionnaires at baseline, with a potential temporal relationship between these factors. CONCLUSION: Active social contact is associated with a stepwise reduction in excess dementia risk and potentially eliminate excess risk of dementia with high neuroticism individuals, supporting social contact as a preventive strategy to attenuate excess risks of dementia from neuroticism personality trait.

3.
J Am Chem Soc ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38717106

RESUMO

Here we report the first and concise total synthesis of a complex ophiobolin-derived sesterterpene, bipolarolide D, which hinges on two strategic applications of pentafulvene: (1) enantioselective pentafulvene-involved [6+2] cycloaddition; (2) regioselective and diastereoselective pentafulvene-involved Heck cyclization. Late-stage selective allylic addition to the ketone moiety facilitates the successful installation of the side chain. This strategy enabled the accomplishment of its first enantioselective total synthesis through a modular approach. This synthesis will facilitate the investigation of relevant biological activities and provide a synthetic blueprint for utilizing fulvenes as versatile synthons in other complex natural product synthesis.

4.
Nanomaterials (Basel) ; 14(9)2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38727344

RESUMO

Tellurium exhibits exceptional intrinsic electronic properties. However, investigations into the modulation of tellurium's electronic properties through physical modification are notably scarce. Here, we present a comprehensive study focused on the evolution of the electronic properties of tellurium crystal flakes under plasma irradiation treatment by employing conductive atomic force microscopy and Raman spectroscopy. The plasma-treated tellurium experienced a process of defect generation through lattice breaking. Prior to the degradation of electronic transport performance due to plasma irradiation treatment, we made a remarkable observation: in the low-energy region of hydrogen plasma-treated tellurium, a notable enhancement in conductivity was unexpectedly detected. The mechanism underlying this enhancement in electronic transport performance was thoroughly elucidated by comparing it with the electronic structure induced by argon plasma irradiation. This study not only fundamentally uncovers the effects of plasma irradiation on tellurium crystal flakes but also unearths an unprecedented trend of enhanced electronic transport performance at low irradiation energies when utilizing hydrogen plasma. This abnormal trend bears significant implications for guiding the prospective application of tellurium-based 2D materials in the realm of electronic devices.

5.
Nat Commun ; 15(1): 3017, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589414

RESUMO

Diode effects are of great interest for both fundamental physics and modern technologies. Electrical diode effects (nonreciprocal transport) have been observed in Weyl systems. Optical diode effects arising from the Weyl fermions have been theoretically considered but not probed experimentally. Here, we report the observation of a nonlinear optical diode effect (NODE) in the magnetic Weyl semimetal CeAlSi, where the magnetization introduces a pronounced directionality in the nonlinear optical second-harmonic generation (SHG). We demonstrate a six-fold change of the measured SHG intensity between opposite propagation directions over a bandwidth exceeding 250 meV. Supported by density-functional theory, we establish the linearly dispersive bands emerging from Weyl nodes as the origin of this broadband effect. We further demonstrate current-induced magnetization switching and thus electrical control of the NODE. Our results advance ongoing research to identify novel nonlinear optical/transport phenomena in magnetic topological materials and further opens new pathways for the unidirectional manipulation of light.

7.
Micromachines (Basel) ; 15(3)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38542603

RESUMO

In order to enhance the sensitivity of wafer-level vacuum-packaged electric field sensors, this paper proposed a vertical-resonant MEMS electric field sensor based on TGV (Through Glass Via) technology. The microsensor is composed of the electric field sensing cover, the drive cover, and the SOI-based microstructures between them. TGV technology is innovatively used to fabricate the electric field sensing cover and the vertically-driven cover. The external electric field is concentrated and transmitted to the area below the silicon plate in the center of the electric field sensing cover through a metal plate and a metal pillar, reducing the coupling capacitance between the silicon plate and the packaging structure, thereby achieving the enhanced transmission of the electric field. The sensitivity-enhanced mechanism of the sensor is analyzed, and the key parameters of the sensor are optimized through finite element simulation. The fabrication process is designed and realized. A prototype is tested to characterize its performance. The experimental results indicate that the sensitivity of the sensor is 0.82 mV/(kV/m) within the electrostatic electric field ranging from 0-50 kV/m. The linearity of the sensor is 0.65%.

8.
Food Microbiol ; 120: 104449, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431336

RESUMO

This research investigated the presence of Burkholderia gladioli pathovar cocovenenans (BGC) in wet rice and starch products, Tremella, and Auricularia auricula in Guangzhou, China. It examined BGC growth and bongkrekic acid (BA) production in wet rice noodles and vermicelli with varying rice flour, edible starch ratios, and oil concentrations. A qualitative analysis of 482 samples revealed a detection rate of 0.62%, with three positive for BGC. Rice flour-based wet rice noodles had BA concentrations of 13.67 ± 0.64 mg/kg, 2.92 times higher than 100% corn starch samples (4.68 ± 0.54 mg/kg). Wet rice noodles with 4% soybean oil had a BA concentration of 31.72 ± 9.41 mg/kg, 5.74 times higher than those without soybean oil (5.53 ± 1.23 mg/kg). The BA concentration correlated positively (r = 0.707, P < 0.05) with BGC contamination levels. Low temperatures (4 °C and -18 °C) inhibited BGC growth and BA production, while higher storage temperatures (26 °C and 32 °C) promoted BGC proliferation and increased BA production. Reducing edible oil use and increasing edible starch can mitigate the risk of BGC-related food poisoning in wet rice noodles and vermicelli production. Further research is needed to find alternative oils that do not enhance BA production. Strengthening prevention and control measures is crucial across the entire production chain to address BGC contamination and BA production.


Assuntos
Burkholderia gladioli , Oryza , Ácido Bongcréquico/análise , Óleo de Soja/análise , Amido , Contaminação de Alimentos/análise , Farinha/análise
9.
Oncol Lett ; 27(5): 205, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38516688

RESUMO

The identification of patients with craniotomy at high risk for postoperative 30-day mortality may contribute to achieving targeted delivery of interventions. The present study aimed to develop a personalized nomogram and scoring system for predicting the risk of postoperative 30-day mortality in such patients. In this retrospective cross-sectional study, 18,642 patients with craniotomy were stratified into a training cohort (n=7,800; year of surgery, 2012-2013) and an external validation cohort (n=10,842; year of surgery, 2014-2015). The least absolute shrinkage and selection operator (LASSO) model was used to select the most important variables among the candidate variables. Furthermore, a stepwise logistic regression model was established to screen out the risk factors based on the predictors chosen by the LASSO model. The model and a nomogram were constructed. The area under the receiver operating characteristic (ROC) curve (AUC) and calibration plot analysis were used to assess the model's discrimination ability and accuracy. The associated risk factors were categorized according to clinical cutoff points to create a scoring model for postoperative 30-day mortality. The total score was divided into four risk categories: Extremely high, high, intermediate and low risk. The postoperative 30-day mortality rates were 2.43 and 2.58% in the training and validation cohort, respectively. A simple nomogram and scoring system were developed for predicting the risk of postoperative 30-day mortality according to the white blood cell count; hematocrit and blood urea nitrogen levels; age range; functional health status; and incidence of disseminated cancer cells. The ROC AUC of the nomogram was 0.795 (95% CI: 0.764 to 0.826) in the training cohort and it was 0.738 (95% CI: 0.7091 to 0.7674) in the validation cohort. The calibration demonstrated a perfect fit between the predicted 30-day mortality risk and the observed 30-day mortality risk. Low, intermediate, high and extremely high risk statuses for 30-day mortality were associated with total scores of (-1.5 to -1), (-0.5 to 0.5), (1 to 2) and (2.5 to 9), respectively. A personalized nomogram and scoring system for predicting postoperative 30-day mortality in adult patients who underwent craniotomy were developed and validated, and individuals at high risk of 30-day mortality were able to be identified.

10.
Front Public Health ; 12: 1343293, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38356947

RESUMO

Background: Occupational burnout is intricately linked to a spectrum of physical disorders encompassing respiratory, cardiovascular, and gastrointestinal conditions, as well as manifestations such as headaches, type 2 diabetes, elevated cholesterol levels, chronic fatigue, and muscle pain. Despite this association, there remains a paucity of research on the specific risk factors contributing to burnout among nurses in China. Methods: This cross-sectional study utilized convenience sampling to recruit participants, with data analyzed from 1,774 nurse staffs. Psychosocial traits were assessed using the Three-Item Loneliness Scale for loneliness, the Generalized Anxiety Disorder 7-item scale (GAD-7) for anxiety symptoms, the 9-item Patient Health Questionnaire (PHQ-9) for depressive symptoms, the Connor Davidson Resilience Scale-10 item (CDRISC-10) for resilience, and the Maslach Burnout Inventory-Human Service Survey (MBI-HSS) for burn out. Restrictive cubic spline analysis to investigate the dose-response relationship between years of experience and burn out. Multivariate linear regression was employed to investigate the relationship between burnout and various risk factors. Results: After controlling for basic demographic variables, good sleep quality was associated with a reduction in emotional exhaustion (ß = -0.307, p < 0.001), while loneliness (ß = 1.334, p < 0.001), depressive symptoms (ß = 0.896, p < 0.001), and anxiety symptoms (ß = 0.504, p < 0.001) were significantly associated with increased emotional exhaustion. Moreover, higher levels of resilience were positively associated with personal accomplishment (ß = 0.635, p < 0.001). Regarding depersonalization, loneliness (ß = 0.577, p < 0.001), depressive symptoms (ß = 0.429, p < 0.001), and anxiety symptoms (ß = 0.152, p < 0.01) were found to increase its level. Conversely, good resilience was associated with a decrease in depersonalization (ß = -0.069, p < 0.001). The non-liner association between year of experience and emotional exhaustion was significantly (p < 0.05). Conclusion: Our findings revealed that significant risk factors contributing to burnout among nursing staff including bad sleep quality, loneliness, lower level of resilience, anxiety symptoms, depressive symptoms. Moreover, a nonlinear correlation between years of experience and the likelihood of experiencing emotional exhaustion was exist.


Assuntos
Esgotamento Profissional , Diabetes Mellitus Tipo 2 , Recursos Humanos de Enfermagem , Testes Psicológicos , Autorrelato , Humanos , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Estudos Transversais
11.
Indian J Pathol Microbiol ; 67(1): 128-132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38358201

RESUMO

Background: The incidence of thyroid tumor is increasing, and preoperative diagnosis of hyalinizing trabecular tumor (HTT) is difficult. Aim: To investigate the cytological features of HTT of the thyroid gland. Settings and Design: A retrospective observational study. Materials and Methods: Ultrasonography, preoperative needle aspiration cytology, postoperative histopathology, immunohistochemistry, and BRAF V600E gene test were performed in five patients with HTT to analyze the pathological characteristics of the patients and review the relevant literature. Results: Four female and one male patients with HTT were recruited. Fine-needle aspiration cytology (FNAC) showed bloodstained background tumor cells with multiple morphologies. The tumor cells exhibited ovoid nuclei, abundant cytoplasm, fine chromatin, nuclear crowding and overlapping, and small nucleoli. Focal nuclear pseudoinclusions and grooves were present. No papillary structures or psammoma bodies were observed. In all cases, tumor cells were radially distributed around the eosinophilic extracellular matrix. In 40% (2 in 5) of cases, trabecular patterns of elongated tumor cells were present, with their nuclei staggered along the longitudinal axis of tumor cells in the trabeculae. FNAC suggested two cases of HTT and three cases of papillary thyroid cancer. Post-operational biopsy indicated they were HTT cases. Conclusion: HTT is a rare thyroid tumor with non-specific clinical manifestations. It can be misinterpreted as papillary thyroid carcinoma by FNAC. However, its cytomorphological traits are helpful in the diagnosis. In combination with FNAC, immunohistochemistry, and molecular testing, HTT can be accurately diagnosed.


Assuntos
Neoplasias da Glândula Tireoide , Humanos , Masculino , Feminino , Biópsia por Agulha Fina , Neoplasias da Glândula Tireoide/patologia , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/genética , Imuno-Histoquímica
12.
Front Neurosci ; 18: 1334508, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38379757

RESUMO

Objectives: The diverse nature of stroke necessitates individualized assessment, presenting challenges to case-control neuroimaging studies. The normative model, measuring deviations from a normal distribution, provides a solution. We aim to evaluate stroke-induced white matter microstructural abnormalities at group and individual levels and identify potential prognostic biomarkers. Methods: Forty-six basal ganglia stroke patients and 46 healthy controls were recruited. Diffusion-weighted imaging and clinical assessment were performed within 7 days after stroke. We used automated fiber quantification to characterize intergroup alterations of segmental diffusion properties along 20 fiber tracts. Then each patient was compared to normative reference (46 healthy participants) by Mahalanobis distance tractometry for 7 significant fiber tracts. Mahalanobis distance-based deviation loads (MaDDLs) and fused MaDDLmulti were extracted to quantify individual deviations. We also conducted correlation and logistic regression analyses to explore relationships between MaDDL metrics and functional outcomes. Results: Disrupted microstructural integrity was observed across the left corticospinal tract, bilateral inferior fronto-occipital fasciculus, left inferior longitudinal fasciculus, bilateral thalamic radiation, and right uncinate fasciculus. The correlation coefficients between MaDDL metrics and initial functional impairment ranged from 0.364 to 0.618 (p < 0.05), with the highest being MaDDLmulti. Furthermore, MaDDLmulti demonstrated a significant enhancement in predictive efficacy compared to MaDDL (integrated discrimination improvement [IDI] = 9.62%, p = 0.005) and FA (IDI = 34.04%, p < 0.001) of the left corticospinal tract. Conclusion: MaDDLmulti allows for assessing behavioral disorders and predicting prognosis, offering significant implications for personalized clinical decision-making and stroke recovery. Importantly, our method demonstrates prospects for widespread application in heterogeneous neurological diseases.

13.
Ecotoxicol Environ Saf ; 273: 116125, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38394755

RESUMO

2-Methylfuran (2-MF) is an important member of the furan family generated during food thermal processing. An in-vivo multiple endpoint genotoxicity assessment system was applied to explore the genotoxic mode of action and threshold of 2-MF. Male Sprague-Dawley rats received 2-MF by oral gavage at doses of 0.16, 0.625, 2.5, and 10 mg/kg.bw/day for 120 days. An additional 15 days were granted for recovery. The Pig-a gene mutation frequency of RET and RBC showed significant increases among the 2-MF groups on day 120. After a 15-day recovery period, the Pig-a gene mutation frequency returned to levels similar to those in the vehicle control. The tail intensity (TI) values of peripheral blood cells at a dose of 10 mg/kg.bw/day significantly increased from day 4 and remained at a high level after the recovery period. No statistical difference was found in the micronucleus frequency of peripheral blood between any 2-MF dose group and the corn oil group at any timepoint. 2-MF may not induce the production of micronuclei, but it could cause DNA breakage. It could not be ruled out that 2-MF may accumulate in vivo and cause gene mutations. Hence, DNA, other than the spindle, may be directly targeted. The mode of action of 2-MF may be that it was metabolized by EPHX1 to more DNA-active metabolites, thus leading to oxidative and direct DNA damage. The point of departure (PoD) of 2-MF-induced genotoxicity was derived as 0.506 mg/kg bw/day.


Assuntos
Dano ao DNA , Reticulócitos , Ratos , Animais , Masculino , Ratos Sprague-Dawley , Testes para Micronúcleos , Reticulócitos/metabolismo , Furanos/toxicidade , Furanos/metabolismo , DNA/metabolismo , Testes de Mutagenicidade
14.
Gen Hosp Psychiatry ; 87: 92-102, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38382421

RESUMO

OBJECTIVE: Poor sleep quality is common in patients with cancer, but the prevalence rates varied widely across studies. This systematic review and meta-analysis examined the pooled prevalence of poor sleep quality among patients with cancer. METHODS: Systematic literature searches were independently conducted in the major databases (Web of Science, PubMed, EMBASE and PsycINFO). Studies that reported the prevalence of poor sleep quality in patients with cancer were analyzed using a random effects model. Funnel plots and Egger's tests were used to assess publication bias. Statistical analyses were performed using R software. RESULTS: A total of 59 epidemiological studies involving 16,223 patients were included. The pooled prevalence of poor sleep quality in patients with cancer was 57.4% [95% confidence interval (CI): 53.3% - 61.6%]. Additionally, three comparative studies with 372 patients and 412 healthy controls were included. Compared to healthy controls, patients with cancer had a significantly higher risk for poor sleep quality [odd ratio (OR) = 3.0; 95%CI: 1.2-7.2; P < 0.05]. Subgroup analyses of the studies revealed that studies from Middle East & North Africa region and low income countries, and on gynecological cancer as well as those with a lower cut-off value of sleep quality (all P < 0.01) reported a higher prevalence of poor sleep quality. Meta-regression analyses showed that higher prevalence of poor sleep quality was associated with higher prevalence of comorbid depression (P < 0.05) and anxiety (P < 0.01), but was associated with a lower education level (P < 0.05) and alcohol use ratio (P < 0.05). CONCLUSION: Poor sleep quality is common among patients with cancer. Considering the overall high prevalence rate and negative impact of poor sleep quality, appropriate measures to identify and improve poor sleep quality are needed to enhance the clinical outcomes in this group.


Assuntos
Neoplasias , Qualidade do Sono , Humanos , Prevalência , Comorbidade , Consumo de Bebidas Alcoólicas , Neoplasias/epidemiologia
15.
Biomed Opt Express ; 15(2): 715-724, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38404297

RESUMO

A novel real-time optical phase sensing method based on the Mach-Zehnder interference principle has been proposed for the detection of calreticulin (CRT) levels in human serum samples. In this approach, anti-CRT antibodies are utilized to capture CRT molecules in serum, leading to a phase shift in both the measuring and reference arms of the system. By employing the concept of weak amplification within the framework of weak measurements, it becomes feasible to continuously monitor the response of CRT in real-time, allowing for the precise determination of serum CRT content at the picomolar level. Our achievement may pave the way in establishing CRT as a diagnostic biomarker for a wide range of medical applications, including rheumatoid arthritis.

16.
Biomimetics (Basel) ; 9(2)2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38392162

RESUMO

Teleoperated robots have attracted significant interest in recent years, and data gloves are one of the commonly used devices for their operation. However, existing solutions still encounter two challenges: the ways in which data gloves capture human operational intentions and achieve accurate mapping. In order to address these challenges, we propose a novel teleoperation method using data gloves based on fuzzy logic controller. Firstly, the data are collected and normalized from the flex sensors on data gloves to identify human manipulation intentions. Then, a fuzzy logic controller is designed to convert finger flexion information into motion control commands for robot arms. Finally, experiments are conducted to demonstrate the effectiveness and precision of the proposed method.

17.
ACS Biomater Sci Eng ; 10(2): 975-986, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38236143

RESUMO

Diabetic skin wounds are difficult to heal quickly due to insufficient angiogenesis and prolonged inflammation, which is an urgent clinical problem. To address this clinical problem, it becomes imperative to develop a dressing that can promote revascularization and reduce inflammation during diabetic skin healing. Herein, a multifunctional collagen dressing (CTM) was constructed by loading large efficacy-potentiated exosome-mimicking nanovesicles (L-Meseomes) into a porous collagen sponge with transglutaminase (TGase). L-Meseomes were constructed in previous research with the function of promoting cell proliferation, migration, and angiogenesis and inhibiting inflammation. CTM has a three-dimensional porous network structure with good biocompatibility, swelling properties, and degradability and could release L-Meseome slowly. In vitro experiments showed that CTM could promote the proliferation of fibroblasts and the polarization of macrophages to the anti-inflammatory phenotype. For in vivo experiments, on the 21st day after surgery, the wound healing rates of the control and CTM were 83.026 ± 4.17% and 93.12 ± 2.16%, respectively; the epidermal maturation and dermal differentiation scores in CTM were approximately four times that of the control group, and the skin epidermal thickness of the CTM group was approximately 20 µm, which was closest to that of normal rats. CTM could significantly improve wound healing in diabetic rats by promoting anti-inflammation, angiogenesis, epidermal recovery, and dermal collagen deposition. In summary, the multifunctional collagen dressing CTM could significantly promote the healing of diabetic skin wounds, which provides a new strategy for diabetic wound healing in the clinic.


Assuntos
Diabetes Mellitus Experimental , Exossomos , Ratos , Animais , Porosidade , Colágeno/farmacologia , Colágeno/uso terapêutico , Cicatrização , Bandagens , Inflamação
18.
ACS Appl Mater Interfaces ; 16(1): 1217-1224, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38164790

RESUMO

All-inorganic wide-bandgap perovskite CsPbI2Br has attracted much attention because of its inherent thermal stability and ideal bandgap for the front subcell of tandem solar cells (TSCs). However, the low power conversion efficiency (PCE) and poor moisture stability of CsPbI2Br still restrict its future commercialization. Herein, zirconium tetrachloride (ZrCl4) was doped into CsPbI2Br films to modulate the crystal growth and improve the film quality. The partial substitution of the B-site Pb2+ of CsPbI2Br with Zr4+ suppresses the unwanted phase conversion from the crystallized black α-phase to the δ-phase, resulting in improved phase stability. Consequently, the humidity and thermal stability of the film are greatly improved. Additionally, the incorporation of ZrCl4 suppresses nonradiative recombination and forms a matched energy-level alignment with the hole-transport layer (Spiro-OMeTAD). Benefiting from these features, the ZrCl4-doped CsPbI2Br perovskite solar cell (PSC) shows an outstanding efficiency of 16.60% with a high open-circuit voltage of 1.29 V. The unencapsulated devices simultaneously show excellent humidity and thermal stability, retaining over 91% of PCEinitial after 1000 h of aging in ambient air conditions and 92% PCEinitial after 500 h of continuous heating at 85 °C in a nitrogen environment, respectively. Furthermore, ZrCl4-doped CsPbI2Br was employed as the front subcell of perovskite/organic TSCs and achieved a remarkable PCE of 19.42%, showing great potential for highly efficient and stable TSCs.

19.
RSC Adv ; 14(3): 1602-1611, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38179093

RESUMO

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is widely used because of its excellent performance. We report the synthesis of two PEDOT:PSS dispersions. The two dispersions differ by the addition of additional protonic acid in the oxidative polymerization system. Although there are examples of the introduction of acids into the polymerization system, the effects of acid on the structure and properties of these materials, in particular their mechanisms of action, have not been elucidated. We describe the chemical structure and molecular weight of two PEDOT polymers using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, UV-vis-NIR spectroscopy, and density functional theory calculations. The carrier concentration, carrier mobility, and surface morphology of the composites are characterized by UV-vis-NIR spectroscopy, electron spin resonance, Raman spectra, Hall effect measurements, and atomic force microscopy. The crystallinity of PEDOT:PSS was measured by X-ray diffraction patterns. We show that the addition of a proper amount of protonic acid to the oxidative polymerization system can effectively reduce the formation of the terminal carbonyl group of PEDOT chains, which is conducive to the growth of polymer chains, and further improve the carrier concentration, which leads to an improvement of conductivity. Our results highlight the optimization of the chemical structure of PEDOT in order to increase its molecular weight and ultimately its conductivity.

20.
Schizophr Res ; 264: 407-415, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38241784

RESUMO

OBJECTIVE: Poor sleep quality is common in patients with schizophrenia but estimated prevalence rates in this population have been mixed. This systematic review and meta-analysis examined the prevalence of poor sleep quality in schizophrenia samples and moderators of prevalence from epidemiological studies as well as the risk of poor sleep quality in schizophrenia patients based on case-control studies. METHODS: Both international (PubMed, Web of Science, PsycINFO, EMBASE) and Chinese databases [Chinese Nation knowledge Infrastructure (CNKI) and WANFANG] were systematically searched. Studies that estimated the prevalence of poor sleep quality in schizophrenia were analyzed using a random effects model. Funnel plots and Egger's tests were used to assess publication bias. Statistical analyses were performed using R software. RESULTS: In total, 23 epidemiological studies and nine case-control studies were included. Based on the epidemiological studies, the pooled overall prevalence of poor sleep quality was 63.4 % [95 % confidence interval (CI): 57.0 %-69.9 %]. Additionally, based on the nine case-control studies, schizophrenia patients had a significantly higher risk for poor sleep quality compared to healthy controls [odd ratio (OR) = 4.5; 95%CI: 2.4-8.3; P < 0.0001]. CONCLUSION: Poor sleep quality is common among schizophrenia patients. Considering negative outcomes caused by poor sleep quality, regular screening on poor sleep quality should be conducted and effective interventions should be provided to those in need.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/epidemiologia , Qualidade do Sono , Estudos de Casos e Controles , Projetos de Pesquisa , Prevalência
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