RESUMEN
BACKGROUND: Lung cancer is one of the most common malignant tumors, and asbestos exposure was suggested to contribute to a proportion of lung cancer cases. Previous genome-wide gene-environment interaction analysis reported that rs13383928 was associated with asbestos-related lung cancer. However, the mechanism of this association was still unclear. METHODS: In the present study, we retrieved the genotype data from the 1,000 Genomes Project on single-nucleotide polymorphisms (SNPs) surrounding rs13383928 and analyzed the linkage disequilibrium (LD) pattern of this region. Further functional genomics analyses were performed. RESULTS: The result indicated that no other SNPs were in LD with rs13383928, suggesting that rs13383928 is the causal one. The following dual luciferase assay disclosed that the T allele of rs13383928 presented significantly higher enhancer activity than G in lung cells, thus verifying that this SNP was functional in the lung. Through chromosome conformation capture, the PTH2R (parathyroid hormone 2 receptor)promoter was identified to interact with the segment surrounding rs13383928. By chromatin immunoprecipitation, it was observed that the region spanning rs13383928 could bind transcription factor FOXJ2 (forkhead box J2). CONCLUSION: Our functional genomics evidence supports a link between rs13383928 and asbestos-related lung cancer through regulating PTH2R.
RESUMEN
BACKGROUND: Acute respiratory infections (ARI) cause considerable morbidity and mortality worldwide, especially in children. Unfortunately, there are limited multi-center data on common viral respiratory infections in south China. METHODS: A total of 4403 nasal swabs were collected from children in 10 cities in Guangdong, China in 2019. Seven respiratory viruses, influenza A virus (IFA), influenza B virus (IFB), respiratory syncytial virus (RSV), adenoviruses (ADV) and parainfluenza virus types 1-3 (PIV1, PIV2 and PIV3), were detected by direct immunofluorescence antibody assay. The personal information and clinical characteristics were recorded and analyzed. RESULTS: The results showed that at least one virus was detected in 1099 (24.96 %) samples. The detection rates of RSV, IFA, ADV, PIV3, PIV1 and PIV2 were 7.13 % (314/4403), 5.31 % (234/4403), 4.02 % (177/4403), 3.04 % (134/4403), 1.70 % (75/4403) and 1.16 % (51/4403), respectively. The detection rate of RSV was highest in 0-6-month-old children at 18.18 % (106/583), while the detection rate of IFA was highest in 12-18-year-old children at 20.48 % (17/83). The total detection rates in winter and spring were 35.67 % (219/614) and 34.56 % (403/1166), higher than those in summer, 17.41 % (284/1631), and autumn, 19.46 % (193/992). CONCLUSIONS: RSV and IFA were the main respiratory viruses in children. With increasing age the detection rate of RSV decreased in children, but the trends for the detection rates of IFA and IFB were the opposite. This study provided the viral etiology and epidemiology of pediatric patients with ARI in Guangdong, China.
Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Virus , Adolescente , Niño , China/epidemiología , Hospitales , Humanos , Lactante , Recién Nacido , Infecciones por Virus Sincitial Respiratorio/diagnóstico , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/diagnóstico , Infecciones del Sistema Respiratorio/epidemiologíaRESUMEN
BACKGROUND: Consolation is a type of empathy-like behavior that has recently been observed in some socially living rodents. Despite the growing body of literature suggesting that stress affects empathy, the relationship between stress and consolation remains understudied at the preclinical level. Here, we examined the effects of chronic emotional stress or physical stress exposure on consolation and emotional behaviors by using the socially monogamous mandarin vole (Microtus mandarinus) in both males and females. METHOD/RESULTS: Physical stress voles were exposed to 14-day social defeat stress, whereas emotional stress voles vicariously experienced the defeat of their partners. We found that physical stress, but not emotional stress, voles showed reduced grooming toward their defeated partners and increased anxiety- and despair-like behaviors. Meanwhile, physical stress voles exhibited decreased neural activity in the anterior cingulate cortex, which is centrally involved in empathy. The densities of oxytocin receptors, dopamine D2 receptors, and serotonin 1A-receptors within the anterior cingulate cortex were significantly decreased in the physical stress group compared with controls. All the behavioral and physiological changes were similar between the sexes. Finally, we found that the reduced consolation behavior and some anxiety-like syndromes in physical stress voles could be alleviated by pretreatment with an oxytocin receptor, D2 receptors, or serotonin 1A-receptor agonist within the anterior cingulate cortex, whereas injections of corresponding receptor antagonists to the control voles decreased the consolation behavior and increased some anxiety-like behaviors. CONCLUSIONS: Our results indicated that chronic physical stress exposure impaired consolation and induced anxiety-like behaviors in mandarin voles and oxytocin receptors, 5-HT1A receptors, and D2 receptors within the anterior cingulate cortex may play important roles in these processes.
Asunto(s)
Conducta Animal , Empatía , Giro del Cíngulo/metabolismo , Oxitocina/metabolismo , Receptor de Serotonina 5-HT1A/metabolismo , Receptores de Dopamina D2/metabolismo , Derrota Social , Estrés Psicológico/metabolismo , Estrés Psicológico/psicología , Agresión , Animales , Arvicolinae , Conducta Animal/efectos de los fármacos , Modelos Animales de Enfermedad , Femenino , Giro del Cíngulo/efectos de los fármacos , Giro del Cíngulo/fisiopatología , Vivienda para Animales , Masculino , Neurotransmisores/farmacología , Transducción de Señal , Estrés Psicológico/fisiopatología , Factores de TiempoRESUMEN
Previous studies showed that protein extract from head-foot tissue of Oncomelania hupensis (O. hupensis) (PhfO), when cocultured with mother sporocysts of Schistosoma japonicum (S. japonicum), was beneficial for parasite's growth and development but the underlying mechanisms remain unclear. One possible strategy for PhfO to promote the growth and development of mother sporocysts of S. japonicum is to upregulate parasite's survival genes. Fructose-1,6-bisphosphate aldolase (ALD), an essential enzyme of glycometabolism in the energy metabolism process, plays an important role in the survival and the growth and development of schistosomes. Using an in vitro coculture system, in this study, we analyzed the potential involvement of the ald gene in the growth and development of mother sporocysts of S. japonicum following coculture with PhfO. We found that coculture with PhfO promoted the growth and development and the survival of mother sporocysts, and increased parasites' ATP consumption level. Mother sporocysts cocultured with PhfO showed a significantly increased expression of the ald gene at both RNA and protein levels. The ALD protein mainly expressed in the cytoplasm of mother sporocysts. Knockdown of ald gene in parasites decreased the ALD protein expression and the ATP consumption level, suppressed the growth and development, and attenuated the survival of mother sporocysts. In ald knockdown mother sporocysts, the effects of PhfO on the ALD expression, the ATP consumption level, the growth and development, and the survival of larvae were significantly abolished. Therefore, the data suggest that PhfO could promote the growth and development, and the survival of mother sporocysts of S. japonicum via upregulating the expression of the ald gene.
Asunto(s)
Fructosa-Bifosfato Aldolasa/genética , Oocistos/crecimiento & desarrollo , Schistosoma japonicum/crecimiento & desarrollo , Caracoles/metabolismo , Extractos de Tejidos/farmacología , Activación Transcripcional/efectos de los fármacos , Animales , Fructosa-Bifosfato Aldolasa/biosíntesis , Larva/crecimiento & desarrollo , Regulación hacia ArribaRESUMEN
Adhesive hydrogel-based evaporative cooling, which necessitates no electricity input, holds promise for reducing energy consumption in thermal management. Herein, inspired by the surface attachment of mussel adhesive proteins via abundant dynamic covalent bonds and noncovalent interactions, we propose a facile strategy to fabricate a self-adhesive cooling hydrogel (Li-AA-TA-PAM) using a copolymer of acrylamide (AM) and acrylic acid (AA) as the primary framework. The monomers formed hydrogen bonds between their carboxyl and amide groups, while tannic acid (TA), rich in catechol groups, enhances the adhesion of the hydrogel through hydrogen bonding. The hydrogel demonstrated strong adhesion to various material surfaces, including plastic, ceramic, glass, and metal. Even under high-speed rotation, it still maintains robust adhesion. The adhesion strength of the Li-AA-TA-PAM hydrogel to aluminum foil reached an impressive value of 296.875 kPa. Interestingly, the excellent contact caused by robust adhesion accelerates heat transfer, resulting in a rapid cooling performance, which mimics the perspiration of mammals. Lithium bromide (LiBr) with hydroactively sorptive sites is introduced to enhance sorption kinetics, thereby extending the effective cooling period. Consequently, the operation temperature of commercial polycrystalline silicon solar cells was reduced by 16 °C under an illumination of 1 kW m-2, and the corresponding efficiency of energy conversion was increased by 1.14%, thereby enhancing the output properties and life span of solar cells. The strategy demonstrates the potential for refrigeration applications using viscous gels.
RESUMEN
Background: Epidemiological studies have shown that early-life nutritional deficiencies are associated with an increased risk of diseases later in life. This study aimed to explore the correlation between famine exposure during the early stages of life and cataracts. Methods: We included 5,931 participants from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) 2018 cross-sectional data in our study. Subjects were categorized into three groups by their age during the famine: adulthood group, school age famine exposure group, and teenage famine exposure group. Utilizing binary logistic regression models, we investigated the relationship between early-life famine exposure and cataracts. Results: Compared to the adulthood group, both the school age exposure group (OR = 2.49, 95%CI = 1.89-3.27) and teenage exposure group (OR = 1.45, 95%CI = 1.20-1.76) had a heightened risk of developing cataracts in elderly stage. And the sex differences in the impact of famine during early years on elderly cataract risk were observed, particularly indicating a higher risk among women who experienced childhood famine compared to men with similar exposure. Conclusion: Famine exposure during the early stages of life is associated with a heightened risk of developing cataracts in old age. To prevent cataracts in elderly individuals, particularly in females, measures should be taken to address nutritional deficiencies in these specific periods.
RESUMEN
Astragalus membranaceus (AM) is a traditional Chinese herbal medicine extensively utilized in vascular cognitive impairment (VCI) treatment. However, due to the complex components of AM, its exact molecular mechanism remains unclear. Therefore, this study investigated the target and molecular mechanism of AM to treat VCI based on network pharmacology and molecular docking. Firstly, the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform, STITCH, and SwissTargetPrediction were utilized to gather the primary active ingredients of AM. The potential therapeutic targets of VCI were collected through GeneCards, OMIM, and DisGeNET databases. Secondly, the protein-protein interaction network was built using the STRING database. The enrichment analysis of gene ontology and the Kyoto Encyclopedia of Genes and Genome pathways was carried out in the R language. Finally, The network topology calculation of Cytoscape software was combined with module analysis to predict the binding properties of its active ingredients and targets. Twenty effective compounds and 733 targets were screened from AM, among which 158 targets were seen as possible targets of AM to treat VCI. MAPK3 and MMP9 were the critical targets of AM intervention in VCI. The crucial pathways include PI3K/Akt, MAPK, Rap1, and Ras signaling pathways. Besides, calycosin and quercetin might be the potential active compounds of AM for VCI treatment. AM intervenes in VCI through a multi-ingredient, multi-target, and multi-pathway coordination mechanism. These findings provide a foundation for a deeper understanding of the molecular mechanisms by which AM is effective in treating VCI.
Asunto(s)
Disfunción Cognitiva , Medicamentos Herbarios Chinos , Humanos , Simulación del Acoplamiento Molecular , Astragalus propinquus , Farmacología en Red , Fosfatidilinositol 3-Quinasas , Disfunción Cognitiva/tratamiento farmacológico , Medicina Tradicional China , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéuticoRESUMEN
Background: Neonatal disorders are facing serious public health challenges. Previous studies were based on limited data sources and had a narrow geographical scope. We aim to understand the trends of alteration in the burden of neonatal disorders from 1990 to 2019 in 204 countries and territories. Methods: Data were investigated from the Global Burden of Disease Study 2019. First, we visualized the burden of neonatal disorders using the number of cases and the age-standardized incidence rate (ASIR), death rate (ASDR), and disability-adjusted life years (ASR-DALYs) from 1990 to 2019. Second, estimated annual percentage changes (EAPCs) were used to evaluate the temporal trends of disease burden during different periods. Finally, the sociodemographic index (SDI) and human development index (HDI) were used to determine whether there exists a correlation between socioeconomic development level, human development level, and potential burden consequences. Results: Overall, in the past 30 years, the ASIR trends have remained relatively steady, whereas the ASDR and ASR-DALYs have declined. However, the burden of neonatal disorders varied greatly in various regions and countries. Among 21 regions, the ASIR trend had the largest increase in Central Latin America (EAPC = 0.42, 95%CI = 0.33-0.50). Conversely, the ASDR and ASR-DALYs experienced the largest decrease in Central Europe (EAPC = -5.10, 95%CI = -5.28 to 4.93) and East Asia (EAPC = -4.07, 95%CI = -4.41 to 3.73), respectively. Among 204 countries, the ASIR (EAPC = 3.35, 95%CI = 3.13-3.56) trend in Greece displayed the most significant increase, while the ASDR (EAPC = 1.26, 95%CI = 1.01-1.50) and ASR-DALYs (EAPC = 1.26, 95%CI = 1.03-1.49) trends in Dominica experienced the most substantial increase. Furthermore, there was a strong correlation between the EAPCs in ASIR, ASDR, ASR-DALYs, and SDI or HDI in 2019, with some exceptions. In addition, countries with elevated levels of HDI experienced a faster increase in ASDR and ASR-DALYs for neonatal disorders. Conclusion: Although the burden of neonatal disorders shows a downward trend from 1990 to 2019, it is still not optimistic. It is necessary to implement a multi-pronged approach to reduce the increasing burden of neonatal disorders.
Asunto(s)
Costo de Enfermedad , Carga Global de Enfermedades , Humanos , Recién Nacido , Europa (Continente) , Grecia , Salud PúblicaRESUMEN
The underlying mechanisms governing parturition remain largely elusive due to limited knowledge of parturition preparation and initiation. Accumulated evidences indicate that maternal decidua plays a critical role in parturition initiation. To comprehensively decrypt the cell heterogeneity in decidua approaching parturition, we investigate the roles of various cell types in mouse decidua process and reveal previously unappreciated insights in parturition initiation utilizing single-cell RNA sequencing (scRNA-seq). We enumerate the cell types in decidua and identity five different stromal cells populations and one decidualized stromal cells. Furthermore, our study unravels that stromal cells prepare for parturition by regulating local retinol acid (RA) synthesis. RA supplement decreases expression of extracellular matrix-related genes in vitro and accelerates the timing of parturition in vivo. Collectively, the discovery of contribution of stromal cells in parturition expands current knowledge about parturition and opens up avenues for the intervention of preterm birth (PTB).
RESUMEN
The timely onset of female parturition is a critical determinant for pregnancy success. The highly heterogenous maternal decidua has been increasingly recognized as a vital factor in setting the timing of labor. Despite the cell type specific roles in parturition, the role of the uterine epithelium in the decidua remains poorly understood. This study uncovers the critical role of epithelial SHP2 in parturition initiation via COX1 and COX2 derived PGF2α leveraging epithelial specific Shp2 knockout mice, whose disruption contributes to delayed parturition initiation, dystocia and fetal deaths. Additionally, we also show that there are distinct types of epithelium in the decidua approaching parturition at single cell resolution accompanied with profound epithelium reformation via proliferation. Meanwhile, the epithelium maintains the microenvironment by communicating with stromal cells and macrophages. The epithelial microenvironment is maintained by a close interaction among epithelial, stromal and macrophage cells of uterine stromal cells. In brief, this study provides a previously unappreciated role of the epithelium in parturition preparation and sheds lights on the prevention of preterm birth.
Asunto(s)
Fenómenos Bioquímicos , Trabajo de Parto , Nacimiento Prematuro , Animales , Femenino , Humanos , Recién Nacido , Ratones , Embarazo , Parto , ÚteroRESUMEN
This study explored the effect of polyferric chloride (PFC) as a flocculant on waste activated sludge anaerobic digestion. The results verified that PFC has an inhibitory effect on methane production during anaerobic digestion. PFC with a concentration of 40 g/kg total suspended solids reduced methane production from 195 ± 2.10 to 156 ± 1.50 L/kg volatile suspended solids, a decrease of 20.0 ± 0.09%. PFC released hydroxyl polymers and Fe(III). Hydroxy polymers aggregated sludge flocs and hindered the release of dissolved organic matter. Fe(III) induced dissimilar iron reduction processes to contend with methyl-CoM for electrons, thereby further reducing methane production. In addition, PFC enriched iron-reducing bacteria and reduced the abundance of methanogens, resulting in microbial communities that are not conducive to methane production. This article puts forward innovative insights on the role of PFC in biological sludge treatment, which is expected to guide the flocculant selection during wastewater treatment.
Asunto(s)
Compuestos Férricos , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Metano , Eliminación de Residuos LíquidosRESUMEN
The potential effect of polyethyleneimine as a flocculant on anaerobic digestion of sludge was investigated. Polyethyleneimine above 12 g/kg total suspended solids inhibited the entire anaerobic digestion process including solubilization, hydrolysis, acidification, and methanogenesis. The addition of 24 g/kg total suspended solids polyethyleneimine reduced methane production from 167 ± 5 L/kg volatile suspended solids in the control reactor (without polyethyleneimine) to 141 ± 5 L/kg volatile suspended solids. Polyethyleneimine bound to extracellular polymeric substances, thus enhancing sludge agglomeration and hindering the release of organics. Meanwhile, the reduction of cytochrome C impeded electron transport, consequently curbed direct interspecies electron transfer. The adsorption of carbon dioxide by amine groups also hampered methane conversion. This study elucidated the concept that polyethyleneimine reduces mass transfer in anaerobic digestion, providing new insights into the potential behavior of flocculants in sludge treatment.
Asunto(s)
Polietileneimina , Aguas del Alcantarillado , Anaerobiosis , Reactores Biológicos , Metano/metabolismoRESUMEN
A wearable thermoelectric cooler (w-TEC) shows promising prospects in personal thermal management due to its zero emission, high efficiency, lightweight, and long-term stability. The flexible heatsinks are able to promote the cooling effect of coolers, but the cooling capacity of current coolers still has much room for improvement because of the relatively large thermal resistance between the cooler and heatsink. In this work, the two-layer heatsink units composed of hydrogel and nickel foam are fabricated and attached to a thermoelectric cooler via the thermal silica gel. Thanks to the high thermal conductivity of nickel foam and a tight bond between the hydrogel and nickel foam, effective heat conduction from the cooler to the body of the heatsink was achieved. In addition, the discrete heatsink units endow the w-TEC with excellent flexibility. The bending radius of this w-TEC is as small as 7.5 mm, and a long-term temperature reduction of â¼10 °C can be realized at an input current of 0.3 A for a flat or bent w-TEC. In the on-body testing, a stable temperature reduction of 7 °C can be obtained using an AA battery with an input voltage of 1.5 V.
RESUMEN
Wearable thermoelectric generators (w-TEGs) can incessantly convert body heat into electricity to power electronics. However, the low efficiency of thermoelectric materials, tiny terminal temperature difference, rigidity, and negligence of lateral heat transfer preclude broad utilization of w-TEGs. In this work, we employ finite element simulation to find the key factors for simultaneous realization of flexibility and ultrahigh normalized power density. Using melamine foam with an ultralow thermal conductivity (0.03 W/m K) as the encapsulation material, a novel lightweight π-type w-TEG with no heatsink and excellent stretchability, comfortability, processability, and cost efficiency has been fabricated. At an ambient temperature of 24 °C, the maximum power density of the w-TEG reached 7 µW/cm2 (sitting) and 29 µW/cm2 (walking). Under suitable heat exchange conditions (heatsink with 1 m/s air velocity), 32 pairs of w-TEGs can generate 66 mV voltage and 60 µW/cm2 power density. The output performance of our TEG is remarkably superior to that of previously reported w-TEGs. Besides, the practicality of our w-TEG was showcased by successfully driving a quartz watch at room temperature.
RESUMEN
Objective: Anemia is still an unfinished global health problem, and adverse birth weight outcomes have everlasting influences on the health of later life. However, the non-linear connections and breakpoints of maternal hemoglobin with birth weight outcomes are still needed to be further elucidated. We aimed to reveal the non-linear connections between maternal hemoglobin during the third trimester of pregnancy and birth weight, low birth weight (LBW), macrosomia, small for gestational age (SGA), and large for gestational age (LGA) in full-term newborns and elucidate the breakpoints of the connections. Methods: A total of 11,411 singletons, full-term, and live newborns, whose mothers conducted the examination of hemoglobin concentration before delivery, were included in this study. A generalized additive model was used to identify and visualize the non-linear connections between maternal hemoglobin and birth weight outcomes. Piecewise linear regression model was adopted to estimate the breakpoints of the connections and report the non-linear connections in detail. Results: There were inverted "U"-shaped exposure-response connections between maternal hemoglobin concentration and birth weight and the risk of macrosomia. There was an increasing trend of the risk of LBW and a decreased trend of LGA with the increase in maternal hemoglobin concentration. The breakpoints of maternal hemoglobin for birth weight were 100 and 138 g/L, and those for SGA were 97 and 138 g/L. The breakpoints of maternal hemoglobin were 119 g/L for LBW, 105 g/L for macrosomia, and 106 g/L for LGA. When maternal hemoglobin concentration ranged from 100 to 138 g/L, maternal hemoglobin concentration increased per 1 g/L, and birth weight significantly decreased by 2.58 g (95% CI: -3.33, -1.83). When maternal hemoglobin concentration ranged from 97 to 138 g/L, maternal hemoglobin concentration increased per 1 g/L, and the risk of SGA significantly increased by 2% (95% CI: 1%, 3%). When maternal hemoglobin concentration was equal to or lower than 119 g/L, maternal hemoglobin concentration increased per 1 g/L, and the risk of LBW significantly increased by 3% (95% CI: 0%, 5%). When maternal hemoglobin concentration was higher than the breakpoints, the risks of macrosomia (OR = 0.99, 95% CI: 0.98, 0.99) and LGA (OR = 0.99, 95% CI: 0.98, 1.00) declined as the increase of maternal hemoglobin concentration. Conclusions: There were non-linear connections between maternal hemoglobin and birth weight outcomes, and there are breakpoints in the connections. Cost-effective interventions targeting pregnant women in the prevention of abnormal maternal hemoglobin concentration should be taken to reduce the incidence of adverse birth weight outcomes.
RESUMEN
Background: Noise exposure has a significant impact on human health. However, the effect of occupational and residential noise on the risk of pregnancy complications was controversial in the literature. This study looked at previous research and performed a meta-analysis to determine how noise exposure during pregnancy affected the risk of pregnancy complications. Methods: Systematic searches were conducted in PubMed, Web of Science, Scopus, Embase, Ovid, and Cochrane, and all relevant studies were included. Two investigators independently evaluated the eligibility of these studies. The risk of bias in each study and the quality and strength of each outcome was evaluated by using the GRADE approach and Navigation Guide. Random effects meta-analysis model was used. Results: The meta-analysis retrieved 1,461 study records and finally included 11 studies. Occupational noise exposure during pregnancy was associated with preeclampsia (RR = 1.07, 95%CI: 1.04, 1.10). Neither occupational nor residential noise exposure was associated with hypertensive disorders of pregnancy (HDP) (RR = 1.10, 95%CI: 0.96, 1.25 and RR = 1.05, 95%CI: 0.98, 1.11) or gestational diabetes mellitus (GDM) (RR = 0.94, 95%CI: 0.88, 1.00 and RR = 1.06, 95%CI: 0.98, 1.16). Further bias analysis showed that the results were reliable. All outcomes were rated as low in quality and inadequate evidence of harmfulness in strength. Conclusions: Occupational noise exposure could increase the risk of preeclampsia, according to the findings. There was no clear evidence of a harmful effect of noise exposure during pregnancy on HDP or GDM.
RESUMEN
Silver selenide is considered as a promising room temperature thermoelectric material due to its excellent performance and high abundance. However, the silver selenide-based flexible film is still behind in thermoelectric performance compared with its bulk counterpart. In this work, the composition of paper-supported silver selenide film was successfully modulated through changing reactant ratio and annealing treatment. In consequence, the power factor value of 2450.9 ± 364.4 µW/(mK2) at 303 K, which is close to that of state-of-the-art bulk Ag2Se has been achieved. Moreover, a thermoelectric device was fabricated after optimizing the length of annealed silver selenide film via numerical simulation. At temperature difference of 25 K, the maximum power density of this device reaches 5.80 W/m2, which is superior to that of previous film thermoelectric devices. Theoretically and experimentally, this work provides an effective way to achieve silver-selenide-based flexible thermoelectric film and device with high performance.
RESUMEN
Mg3Sb2-based compounds by virtue of nontoxicity and low-cost have become a promising class of candidates for midtemperature thermoelectric power generation. Here, we successfully fabricated n-type Mg3Sb2-based materials using an inexpensive and efficient approach of one-step ball milling and spark plasma sintering, and demonstrate that a complementary and favorable effect of multiple elements coalloying/-doping leads to an excellent thermoelectric performance. The intrinsic p-type conducting behavior for Mg3Sb2 could be changed to n-type through Bi and Se coalloying on Sb sublattices with excess Mg, resulting from the suppression of Mg vacancies and the formation of Mg interstitial. Furthermore, Mn doping on Mg sublattices could soften the chemical bonds, leading to the increase of carrier mobility and concentration simultaneously. Additionally, multielement coalloying/-doping could significantly increase the lattice disorder, which undoubtedly strengthens the phonon scattering and readily results in a suppressed lattice thermal conductivity. As a result, a highest ZT value of 1.6 at 723 K and an average ZT value up to 1.1 were obtained in the temperature range of 323-723 K in the Mg3.18Mn0.02Sb1.5Bi0.49Se0.01 sample, which is one of the highest values among the Te free Mg3Sb2. This work could give guidance for improving the thermoelectric performance of Zintl phase materials or even others using the multielement codoping/-alloying strategy.