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1.
Artigo em Inglês | MEDLINE | ID: mdl-31603524

RESUMO

Heterotaxy syndrome are defined as the disorders that involve abnormal arrangement of viscera. We present a case of prenatally diagnosed heterotaxy syndrome with complex cardiac abnormality in a 29-year-old primigravida woman. In this case, the disturbance of fetal abdominal organs showed a midline liver, asplenia, a right-sided stomach and inferior vena cava on the left side of the spine, presenting the performance of right isomerism. The disturbance of fetal thoracic organs showed two lobar bronchi and four-lobed lungs with bilateral main bronchi, presenting the performance of left isomerism. Fetal cardiac malformations in this case include a stenotic left ventricle, complete atrioventricular septal defect, right aortic arch, pulmonary atresia and anomalous pulmonary venous connection. This type of fetal abdominal right isomerism and thoracic left isomerism with complex cardiac abnormality is rarely reported in prenatally detected cases of heterotaxy syndrome.

2.
Rev Sci Instrum ; 90(9): 094704, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31575239

RESUMO

A three-layer aperture coupled microstrip antenna array (ACMA) is designed and fabricated for wideband high-power microwave (HPM) application, which has not been reported in the field of HPM. In this paper, the proposed antenna array overcomes the disadvantage of low power capacity of traditional microstrip antenna arrays. Moreover, based on the H-shaped aperture coupled structure, it enhances the relative bandwidth up to more than 50%. Compared with traditional HPM antennas, it has advantages of being low-profile (less than 0.2λ), wideband, lightweight, and easy to manufacture. The proposed antenna array consists of 60 elements; each element has four aperture coupled patch antennas fed by a four-way microstrip line power divider. In order to realize the modular design, the antenna array is divided into 10 identical modules; benefiting from this design, machining and assembling become easier. Additionally, cold tests and high-power tests are carried out, and the experimental results show that the ACMA achieves a relative bandwidth of 51.2% for voltage standing-wave ratio < 2 from 1.52 to 2.57 GHz. Consistent with simulation results, the measured gain is more than 28.8 dB in the whole bandwidth and it reaches a maximum of 32.1 dB. Finally, the high-power tests show that the power capacity of the proposed ACMA is greater than 140 MW, which proves the feasibility of the design in wideband HPM application.

3.
Chin J Nat Med ; 17(9): 698-706, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31526505

RESUMO

Seven new isoquinoline alkaloids, 9-(2'-formyl-5', 6'-dimethoxyphenoxy)-1, 2, 3, 10-tetramethoxy dehydroaporphine (1), 9-(2'-formyl-5', 6'-dimethoxyphenoxy)-1, 2, 3, 10-tetramethoxy oxoaporphine (2), 3-methoxy-2'-formyl oxohernandalin (3), (-)-9-(2'-methoxycarbonyl-5', 6'-dimethoxyphenoxy)-1, 2, 3, 10-tetramethoxy aporphine (4), (-)-2'-methoxycarbonyl thaliadin (5), (-)-9-(2'-methoxyethyl-5', 6'-dimethoxyphenoxy)-1, 2, 3, 10-tetramethoxy aporphine (6), (-)-3-methoxy hydroxyhernandalinol (7), together with six known isoquinoline alkaloids (8-13) were isolated from the roots of Thalictrum foetidum. Their structures were elucidated by extensive spectroscopic measurements. Compounds 1 and 2 showed significant selective cytotoxicity against glioma stem cells (GSC-3# and GSC-18#) with IC50 values ranging from 2.36 to 5.37 µg·mL-1.

4.
Nanotechnology ; 31(1): 015602, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509806

RESUMO

Helical-structured metallic nanocoils (NCs) may have special interactions with electromagnetic waves and hence attract considerable attention. Although several fabrication methods for metallic NCs have been reported, it is still challenging to obtain a network of well-shaped metallic NCs. This paper reports a novel and simple approach to fabricate metallic NC network. We show that well-shaped Pt NCs with symmetrical left- and right-handed segments can be formed through a spontaneous progress of mechanical deformation. The mechanisms of the driving force for the self-organization, formation of helical chirality balance, and shape control are demonstrated.

5.
ACS Appl Mater Interfaces ; 11(38): 34854-34861, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31476275

RESUMO

Operando insight into the catalytic kinetics under working conditions is important for further rationalizing the design of advanced catalysts toward efficient renewable energy applications. Here, we enable a ubiquitous carbon material as an efficient acidic oxygen evolution reaction (OER) electrocatalyst, synthesized via a facile and controllable "amino-assisted polymerization and carbonization" strategy. This as-developed metal-free amino-rich hierarchical-network carbon (amino-HNC) framework directly supported on carbon paper can catalyze OER at a quite low overpotential of 281 mV and a small Tafel slope of 96 mV dec-1 in an acid solution, and maintain ∼98% of its initial catalytic activity after 100 h oxygen evolution operation. By using the operando synchrotron infrared spectroscopy, a crucial structurally evolved H2N-(*O-C)-C, formed by adsorbing the *O intermediate on the active H2N-C═C moiety, is observed on amino-HNC electrocatalysts during the OER process in the acid medium. Furthermore, theoretical calculations reveal that the optimization of the sp2 electronic structure of C═C by amino radicals could effectively lower the kinetic formation barrier of the *O intermediate on the H2N-C═C moiety, contributing to a prominent acidic oxygen-involved catalysis.

6.
Anal Chem ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31522496

RESUMO

Aflatoxin B1 (AFB1) contamination is one of the most critical global issues in food safety. The high carcinogenic nature necessitates rapid and specific methods for the determination of AFB1 in foodstuffs at ultratrace levels. Here, we report an enhanced bienzymatic chemiluminescence competitive immunoassay for ultrasensitive and high-throughput determination of AFB1. In this assay, protein G was first coated on the wells of a microplate for recognizing the Fc fragment of anti-AFB1 mAbs to reduce the antibody dosage and guarantee high immunological reaction efficiency. The target AFB1 competed with glucose oxidase labeled AFB1 for the limited anti-AFB1 mAbs in the wells of the microplate. p-Bromophenol was employed as an enhancer to obtain intense and long-lasting chemiluminescence. The utilization of an enhancer and bienzymatic catalysts effectively improved the detection sensitivity. The developed method offered a good linearity over 5 orders of magnitude, a detection limit of 5 pg L-1, and a relative standard deviation of 1.9% for AFB1. The application of the developed method to the analysis of grain samples gave quantitative recoveries from 94.0% to 97.0%. The developed method provides a universal platform for high-throughput, ultrasensitive, and high specific detection of pollutants or nutrients in foods.

7.
Ying Yong Sheng Tai Xue Bao ; 30(8): 2813-2821, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31418207

RESUMO

Understanding the effects of biological organic fertilizer DZF-363 on the growth, root rot diseases, and the structure and function of soil microbial community of Angelica sinensis could provide theoretical basis for the adjustment and improvement of soil environment in the rhizosphere of continuous cropping. Taking 2-year continuous cropping A. sinensis and its rhizosphere soil as test objects, with control (without any pesticides, micro-fertilizer, CK), pesticides groups (15% chlorpyrifos and 50% carbendazim, N), and DZF-363 (DZF) treatments, microbial community structure, and urease and phosphatase activities in rhizosphere soil were figured out by high throughput sequencing and colorimetric method. The results showed that the yield of DZF-363 group was 18.8% higher than CK and 6.8% higher than N. The root rot disease index in the DZF was reduced, with a control effectiveness of 52.0%. The activities of urease, neutral phosphatase and alkaline phosphatase in rhizosphere soil were significantly increased during the growing season, and the urease acti-vity increased by 52.4%, 13.9%, 10.3%, neutral phosphatase activity by 15.5%, 10.2%, 10.3%, alkaline phosphatase activity by 10.3%, 4.4%, 4.0% compared with CK during seedling and middle, and harvesting stages, respectively. The acid phosphatase activity increased by 15.6% and 8.2% at middle and harvesting stages, respectively. The proportion of Actinobacteria in CK, N and DZF groups was 11.3%, 10% and 20%, respectively. The proportion of unidentified Bacillibacteria and Actinobacteria was larger in DZF than in the CK and N groups. The Shannon index was significantly increased by DZF. There was positive correlation between Shannon and Simpson indices with the yield of A. sinensis, while negative correlation with the root rot disease. Therefore, the application of DZF-363 could strongly improve the diversity of soil bacteria in the rhizosphere, alter the soil bacterial community structure and rhizosphere soil urease and phosphatase activities, reduce the occurrence of root rot diseases, and thus increase the yield.


Assuntos
Agricultura/métodos , Angelica sinensis , Fertilizantes , Microbiologia do Solo , Bactérias , Biodiversidade , Rizosfera , Solo
8.
Water Res ; 164: 114911, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31382156

RESUMO

The high pollutant loads discharged from cities pose risks to urban waterways, and in turn the estuarine environments, making it challenging to improve urban liveability. Past studies on the behaviour of pollutants in rivers have largely investigated their transport along the waterway, primarily focusing on the movement of water and sediment. However, the current approaches in pollutant transport modelling provide limited insights into how pollutant transfer between water and sediment phases influences their transport from the upstream towards the estuarine environment. This research study firstly identified typical patterns of metal loads along an urban river in a highly populated city in China. The outcomes were then used to conceptualise metal transfer between water and sediment phases. It was noted that physico-chemical characteristics of water and sediments play a key role in metal transfer between the two phases, and the dominant transfer path (sediment to water/water to sediment) is different between different metals, independent of their origin (crustal, anthropogenic or marine-related). Several scenarios were derived from the conceptualisation of metal behaviour. These in turn were then used to develop real-world scenarios of metal transport in rivers based on the field data. The conceptualisation of metal behaviour confirmed that each metal is likely to have a dominant phase of transport (sediment/water), which is influenced by the dominant transfer path of that metal between water and sediments.

9.
Clin Drug Investig ; 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31432392

RESUMO

BACKGROUND AND OBJECTIVES: New intravenous and solid oral formulations of the antifungal agent posaconazole have been developed. This randomized, open-label, crossover study in 18 healthy adult Chinese male and female subjects evaluated the pharmacokinetics of single-dose posaconazole (oral 300-mg posaconazole tablet fasted, intravenous 300-mg posaconazole solution fasted, and oral 300-mg posaconazole tablet with standard high-fat breakfast). Primary objectives were to determine the single-dose pharmacokinetics of posaconazole in healthy Chinese subjects when administered as an intravenous solution and as an oral tablet under fasted conditions and the effect of food on the absorption of posaconazole. METHODS: The three treatments consisted of the following: a single oral dose of posaconazole 300 mg (fasted), a single oral dose of posaconazole 300 mg (high-fat breakfast), and a single intravenous dose of posaconazole 300 mg (fasted). Blood samples for pharmacokinetic analysis were collected before dosing and at regular intervals after dosing. Adverse events were monitored throughout. The pharmacokinetic population included the per-protocol population. The safety population included all subjects who received one or more doses of the study drug. RESULTS: Time to maximum plasma concentration of intravenous posaconazole coincided with the end of infusion; the half-life (t½) was 25.76 h. Geometric mean (% coefficient of variation) values of area under the plasma concentration-time curve from time 0 extrapolated to infinity (AUC0-∞) and maximum plasma concentration (Cmax) were 59,925 (36.2%) h·ng/mL and 3999 (28.5%) ng/mL, respectively. The posaconazole tablet had a time to maximum plasma concentration of 4 h and a t½ of 25.21 h after fasting. Geometric mean (coefficient of variation) values of AUC0-∞ and Cmax were 25,263 (39.9%) h·ng/mL and 674.5 (29.6%) ng/mL, respectively. Standard high-fat breakfast increased the exposure of posaconazole approximately twofold with geometric mean ratios (high-fat breakfast/fasted) for AUC0-∞ and Cmax of 2.06 (90% confidence interval 1.86-2.30) and 1.95 (90% confidence interval 1.65-2.31), respectively. The geometric mean absolute bioavailability of the tablet formulation was 42.2% in the fasted state and 87.1% under high-fat breakfast conditions. The most commonly reported adverse events were nausea, vomiting, dizziness, and first-degree atrioventricular block for intravenous posaconazole 300 mg and nausea for oral posaconazole 300 mg (high-fat breakfast). All adverse events were mild and resolved without sequelae. CONCLUSIONS: Posaconazole was generally well tolerated in healthy Chinese male and female subjects. The safety and the high-fat breakfast and fasted pharmacokinetics of posaconazole in healthy Chinese subjects are within exposures demonstrated to be generally well tolerated and efficacious and compare reasonably well with the overall posaconazole data across Western countries.

10.
Mol Cell ; 75(3): 644-660.e5, 2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398325

RESUMO

Cell-cell communication via ligand-receptor signaling is a fundamental feature of complex organs. Despite this, the global landscape of intercellular signaling in mammalian liver has not been elucidated. Here we perform single-cell RNA sequencing on non-parenchymal cells isolated from healthy and NASH mouse livers. Secretome gene analysis revealed a highly connected network of intrahepatic signaling and disruption of vascular signaling in NASH. We uncovered the emergence of NASH-associated macrophages (NAMs), which are marked by high expression of triggering receptors expressed on myeloid cells 2 (Trem2), as a feature of mouse and human NASH that is linked to disease severity and highly responsive to pharmacological and dietary interventions. Finally, hepatic stellate cells (HSCs) serve as a hub of intrahepatic signaling via HSC-derived stellakines and their responsiveness to vasoactive hormones. These results provide unprecedented insights into the landscape of intercellular crosstalk and reprogramming of liver cells in health and disease.

11.
Biosens Bioelectron ; 141: 111473, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31272060

RESUMO

Accurate analysis of organophosphate pesticides (OPs) with portable devices remain an elusive goal that have received widespread investigative attention in the areas of environmental contamination and disease prevention. Herein, using all-in-one enzyme-inorganic hybrid nanoflowers (ACC-HNFs) to fabricate high-performance artificial enzyme cascade system, we established a sensitive and affordable lab-on-paper biosensor. This biosensor incorporated disposable screen-printed carbon electrode (SPCE) and colorimetric test strips, which enabled the dual-modal readout (electrochemical and colorimetric signal) for on-site monitoring of OPs, achieving an "on-demand" tuning of the detection performance. Using paraoxon as a model analyte, the ACC-HNFs-based lab-on-paper platform could reach a limit of detection down to the femtogram/mL level (6 fg mL-1). Meticulous design of ACC-HNFs provided a versatile approach for constructing artificial enzyme as a recognizer and amplifier to fill the gap in constructing robust artificial enzyme systems which can be used for on-site contamination monitoring and biological diagnosis.

12.
Int J Biol Sci ; 15(8): 1654-1663, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360108

RESUMO

Metabolic disorders can lead to a scarcity or excess of certain metabolites such as glucose, lipids, proteins, purines, and metal ions, which provide the biochemical foundation and directly contribute to the etiology of metabolic diseases. Nonalcoholic fatty liver disease, obesity, and cancer are common metabolic disorders closely associated with abnormal lipid metabolism. In this review, we first describe the regulatory machinery of lipid metabolism and its deregulation in metabolic diseases. Next, we enumerate and integrate the mechanism of action of some natural compounds, including terpenoids and flavonoids, to ameliorate the development of metabolic diseases by targeting lipid metabolism. Medicinal natural products have an established history of use in health care and therapy. Natural compounds might provide a good source of potential therapeutic agents for treating or preventing metabolic diseases with lipid metabolic abnormalities.

13.
Talanta ; 204: 224-228, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357286

RESUMO

Gold nanoparticles (AuNPs) without surface capping agents are easily aggregated owing to their high surface energy, leading to an unexpected decrease of their catalytic activity. Herein, we report gold nanoparticles decorated covalent organic framework (COF) as mimetic peroxidase for colorimetric detection of mercury. 1,3,5-Tris-(4-formyl-phenyl)triazine (PT) and 4, 4'-azodianiline (Azo) was employed as the monomers to prepare a novel imine based COF PTAzo under solvothermal conditions. AuNPs are further decorated into the PTAzo to form COF-AuNPs hybrid via a citrate reducing method. The COF-AuNPs show high stability, and exhibits enhanced peroxidase mimetic activity in the presence of Hg2+. The Hg2+ concentration dependent peroxidase mimetic activity of COF-AuNPs enables the development of a sensitive and selective method for detection of Hg2+ in aqueous solution. The developed method gives good linearity in the range of 5-300 nM with the limit of detection of 0.75 nM. The results show that Hg2+-enhanced peroxidase mimetic activity of COF-AuNPs offers great potential for the detection of Hg2+ in real samples.

14.
ACS Appl Mater Interfaces ; 11(31): 27605-27614, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31291083

RESUMO

Precise on-site profiling of organophosphate pesticides (OPs) is of significant importance for monitoring pollution and estimating poisoning. Herein, we designed a simple and convenient portable kit based on Ag+-responsive hydrogels for accurate detection of OPs. The newly developed hydrogels employed o-phenylenediamine (OPD) and silicon quantum dots (SiQDs) as indicator, which possessed ratiometric response. In this sensor, OPs as inhibitor of acetylcholinesterase prevented the generation of thiocholine, which blocked the formation of metal-polymer with Ag+, further triggered the oxidation of OPD to yield yellow 2,3-diaminophenazine (DAP) with fluorescence emission at 557 nm. The fluorescence intensity of SiQDs (444 nm) was quenched by DAP through inner filter effect (IFE) process, emerging a typical ratiometric response. Interestingly, the ratiometric signal of kit, which was recorded by smartphone's camera, can be transduced by ImageJ software into the hue parameter that was linearly proportional to the concentration of OPs. The simplicity of portable kit combined with smartphone operation, which possessed high sensitivity (detection limit <10 ng mL-1) and rapid sample-to-answer detection time (45 min) in agricultural sample, indicating that the methodology offered a new sight for portable monitoring of food safety and human health.

15.
Sci China Life Sci ; 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31290095

RESUMO

Artemisia annua is an anti-fever herbal medicine first described in traditional Chinese medicine 1,000 years ago. Artemisinin, the extract of A. annua, and its derivatives (dihydroartemisinin (DHA), artemether, and artesunate) have been used for the treatment of malaria with substantial efficacy. Recently, DHA has also been tested for the treatment of lupus erythematosus, indicating that it may function to balance the immune response in immunocompromised individuals. In the present study, the regulatory effect of artemisinin on the murine immune system was systematically investigated in mice infected with two different protozoan parasites (Toxoplasma gondii and Plasmodium berghei). Our results revealed that the mouse spleen index significantly increased (spleen enlargement) in the healthy mice after DHA administration primarily due to the generation of an extra number of lymphocytes and CD8+ T lymphocytes in both the spleen and circulation. DHA could increase the proportion of T helper cells and CD8+ T cells, as well as decrease the number of splenic and circulatory B cells. Further, DHA could reduce the production of proinflammatory cytokines. Our study revealed that apart from their anti-parasitic activity, artemisinin and its derivatives can also actively modulate the immune system to directly benefit the host.

16.
Dalton Trans ; 48(32): 12193-12198, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31334706

RESUMO

A bis(amidinate) ligand with a rigid o-phenylene linker C6H4-1,2-[NC(tBu)NH(C6H5)]2 (1) was successfully employed for the syntheses of rare-earth amides 2-5 in good yields. The structures of the amides were established by X-ray diffraction analysis and revealed that the ligand framework coordinated to the lanthanide atoms in different fashions depending on the central ion size. Larger lanthanide metal ions La3+ and Nd3+ prefer to form dinuclear complexes with one linked bis(amidinate) ligand as a bridge, while the smaller sized Y3+ and Er3+ favor the formation of mononuclear complexes. These complexes exhibited good catalytic activity for ring-opening polymerization of ε-caprolactone and l-lactide and the mononuclear complexes display higher activity.

17.
Water Sci Technol ; 79(10): 1947-1955, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31294711

RESUMO

Developing substrate with carbon release properties is helpful to enhance nitrogen removal in low C/N ratio wastewater treatment. In this study, substrates with and without adding carbon source and microorganism were prepared to treat the drainage effluent from a wastewater treatment plant (WWTP), the difference in nitrogen removal were investigated. The results showed that adding a carbon source and microorganism to substrates could not only increase the amount of chemical oxygen demand (COD) released, but also enhance the adsorption capacities of NH4+-N and NO3--N. The carbon release process followed the first-order kinetic equation. A nitrogen removal model consisting of four phases of diffusion, adsorption, assimilation and transformation was proposed. In the short term, nitrogen was mainly removed by adsorption; adding microorganism contributed to enhance nitrification and denitrification. In the long-term, nitrogen removal performances were similar whether microorganism was added or not, and microbial species on the surface of substrates were similar. This work suggested when using substrate to treat wastewater for nitrogen removal, preparing a substrate with excellent property for biofilm formation was the most important factor.


Assuntos
Nitrogênio , Eliminação de Resíduos Líquidos , Águas Residuárias , Biodegradação Ambiental , Carbono , Desnitrificação , Microbiologia da Água
19.
J Exp Clin Cancer Res ; 38(1): 300, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31291971

RESUMO

BACKGROUND: Cancer is fundamentally a deregulation of cell growth and proliferation. Cancer cells often have perturbed metabolism that leads to the alteration of metabolic intermediates. Dehydrogenase/reductase member 2 (DHRS2) belongs to short-chain alcohol dehydrogenase/reductase (SDR) superfamily, which is functionally involved in a number of intermediary metabolic processes and in the metabolism of lipid signaling molecules. DHRS2 displays closely association with the inhibition of cell proliferation, migration and quiescence in cancers. METHODS: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4- sulfophenyl)-2H-tetrazolium (MTS), 5-ethynyl-2'-deoxyuridine (EdU) and colony formation assays were applied to evaluate the proliferative ability of nasopharyngeal carcinoma (NPC) cells. We performed lipid metabolite profiling using gas chromatography coupled with mass spectrometry (GC/MS) to identify the proximal metabolite changes linked to DHRS2 overexpression. RNA sequencing technique combined with differentially expressed genes analysis was applied to identify the expression of genes responsible for the anti-tumor effect of trichothecin (TCN), a natural sesquiterpenoid compound isolated from an endophytic fungus. RESULTS: Our current findings reveal that DHRS2 affects lipid metabolite profiling to induce cell cycle arrest and growth inhibition in NPC cells. Furthermore, we demonstrate that TCN is able to induce growth inhibition of NPC in vitro and in vivo by up-regulating DHRS2. CONCLUSIONS: Our report suggests that activating DHRS2 to reprogram lipid homeostasis may be a target for the development of targeted therapies against NPC. Moreover, TCN could be exploited for therapeutic gain against NPC by targeting DHRS2 and it may also be developed as a tool to enhance understanding the biological function of DHRS2.

20.
ACS Appl Mater Interfaces ; 11(28): 25133-25139, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31268650

RESUMO

Although introducing more fillers in nanocages is beneficial to gain low lattice thermal conductivity within filling fraction limit, accompanying high electronic thermal conductivity usually results in an unsatisfactory figure of merit ZT in CoSb3. In this work, Sn is adopted to tailor the electronic transport behavior for a high-filled Yb0.3Co4Sb12 alloy through rapid melt spinning combined with hot-press sintering processes. In spite of the reduced electrical conductivity, the power factors are scarcely influenced due to improved Seebeck coefficients by the reduced carrier concentration and moderate ionized impurity scattering. However, the lower total thermal conductivity is synergistically tuned by the effective suppression of electronic thermal conductivity and the low lattice thermal conductivity. As a result, both the high maximum ZT value of 1.4 at 823 K and the average ZT value of ∼0.98 between 300 and 850 K can be achieved in the Yb0.3Co4Sb11.85Sn0.15 sample. This work illustrates a promising approach for improving thermoelectric properties by largely tuning the electronic thermal conductivity.

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