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1.
Chemistry ; 28(64): e202201834, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-35978556

RESUMO

General strategies for metal aerogel synthesis, including single-metal, transition-metal doped, multi-metal-doped, and nano-metal-doped carbon aerogel are described. In addition, the latest applications of several of the above-mentioned metal aerogels in electrocatalytic CO2 reduction are discussed. Finally, considering the possibility of future applications of electrocatalytic CO2 reduction technology, a vision for industrialization and directions that can be optimized are proposed.

2.
Chemistry ; 28(66): e202201881, 2022 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-36031561

RESUMO

Currently, the excessive consumption of fossil fuels is accompanied by massive emissions of CO2 , leading to severe energy shortages and intensified global warming. It is of great significance to develop and use renewable clean energy while reducing the concentration of CO2 in the atmosphere. Photocatalytic technology is a promising strategy for carbon dioxide conversion. Clearly, the achievement of the above goals largely depends on the design and construction of catalysts. This review is mainly focused on the application of 2D materials for photocatalytic CO2 reduction. The contribution of synthetic strategies to their structure and performance is emphasized. Finally, the current challenges, and prospects of 2D materials for photoreduction of CO2 with high efficiency, even for practical applications are discussed. It is hoped that this review can provide some guidance for the rational design, controllable synthesis of 2D materials, and their application for efficient photocatalytic CO2 reduction.

3.
Phys Chem Chem Phys ; 24(39): 24553-24561, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36193809

RESUMO

Understanding magnetic anisotropy based on electronic properties is vital for theoretical and applied research on ferromagnetic semiconductors. Here, for several representative D3d-symmetric ferromagnetic semiconducting monolayers, we investigate the effects of mixings between d-orbitals of central magnetic atoms and p-orbitals of ligands on magnetocrystalline anisotropy energy (MAE). For high-spin materials, the weakening of p-d mixing increases the electron occupation of spin-up bonding d-orbitals at the expense of the electron occupation in the corresponding spin-down orbitals, In contrast, the weakening of p-d mixing decreases the electron occupation of the spin-up antibonding d-orbitals and enhances the electron occupation in the corresponding spin-down orbitals. The weakening mixings also result in an overall shift of the spin-down band toward a higher energy with respect to the spin-up band. These changes are just the opposite in a low-spin material. More interestingly, we find that the transition point between the bonding and the antibonding spin-up bands plays a significant role in tuning the MAE. Its shift with strain is almost linearly related to the p-d bond strength and significantly affects both the electron occupation of occupied spin-up antibonding d-bands and the band shift of unoccupied spin-up d-bands. Furthermore, the correlation of these mixing-related changes in electronic structures with the MAE is qualitatively and quantitatively analyzed. Our findings can deepen the understanding of the correlation between MAE and p-d orbital mixings and provide theoretical guidance for modulating the MAE.

4.
J Am Chem Soc ; 142(8): 4051-4060, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32017566

RESUMO

Low-cost and earth-abundant PbS-based thermoelectrics are expected to be an alternative for PbTe, and have attracted extensive attentions from thermoelectric community. Herein, a maximum ZT (ZTmax) ≈ 1.3 at 923 K in n-type PbS is obtained through synergistically optimizing quality factor with Sn alloying and PbTe phase incorporation. It is found that Sn alloying in PbS can sharpen the conduction band shape to balance the contradictory interrelationship between carrier mobility and effective mass, accordingly, a peak power factor of ∼19.8 µWcm-1K-2 is achieved. Besides band sharpening, Sn alloying can also narrow the band gap of PbS so as to make the conduction band position between Pb0.94Sn0.06S and PbTe well aligned, which can benefit high carrier mobility. Therefore, incorporating the PbTe phase into the Pb0.94Sn0.06S matrix can not only favorably maintain the carrier mobility at ∼150 cm2V-1s-1 but also suppress the lattice thermal conductivity to ∼0.61 Wm-1K-1 in Pb0.94Sn0.06S-8%PbTe, which contributes to a largely enhanced quality factor. Consequently, an average ZT (ZTave) ≈ 0.72 in 300-923 K is achieved in Pb0.94Sn0.06S-8%PbTe that outperforms other n-type PbS-based thermoelectric materials.

5.
J Cell Mol Med ; 23(5): 3224-3233, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30887657

RESUMO

Long non-coding RNAs have recently become a key regulatory factor for cancers, whereas FER1L4, a newly discovered long non-coding RNA, has been mostly studied in gastric carcinoma and colon cancer cases. The functions and molecular mechanism of FER1L4 have been rarely reported in glioma malignant phenotypes. In this study, it was found that the expression of LncRNA FER1L4 is upregulated in high-grade gliomas than in low-grade cases and that a high expression of LncRNA FER1L4 predicts poor prognosis of gliomas. Meanwhile, in vitro study suggests that expression of FER1L4 with SiRNA knockdown obviously suppresses cell cycle and proliferation. It is further demonstrated by experiments that the FER1L4 knockdown suppresses growth of in vivo glioma. Besides, it is found in our study that LncRNA FER1L4 expression is positively correlated with E2F1 mRNA expression. After knockdown of FER1L4 expression, E2F1 expression is significantly down-regulated, whereas the expression of miR-372 is significantly up-regulated; the up-regulation of miR-372 leads to significant down-regulation of FER1L4 and E2F1 expression. In addition, it is also found that FER1L4 can be used as competitive endogenous RNA to interact or bind with miR-371 and thereby up-regulate E2F1, thus promoting the cycle and proliferation of glioma cells. It may be one of the molecular mechanisms in which FER1L4 plays its oncogene-like role in gliomas.


Assuntos
Fator de Transcrição E2F1/genética , Glioma/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioma/patologia , Humanos
6.
Am J Physiol Gastrointest Liver Physiol ; 317(4): G484-G492, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31369290

RESUMO

Hyperuricemia is associated with many metabolic diseases. However, the underlying mechanism remains unknown. The gut microbiota has been demonstrated to play significant roles in the immunity and metabolism of the host. In the present study, we constructed a hyperuricemic mouse model to investigate whether the metabolic disorder caused by hyperuricemia is related to intestinal dysbiosis. A significantly increased intestinal permeability was detected in hyperuricemic mice. The difference in microflora between wild-type and hyperuricemic mice accompanies the translocation of gut microbiota to the extraintestinal tissues. Such a process is followed by an increase in innate immune system activation. We observed increased LPS and TNF-α levels in the hyperuricemic mice, indicating that hyperuricemic mice were in a state of low-grade systemic inflammation. In addition, hyperuricemic mice presented early injury of parenteral tissue and disordered lipid metabolism. These findings suggest that intestinal dysbiosis due to an impaired intestinal barrier may be the key cause of metabolic disorders in hyperuricemic mice. Our findings should aid in paving a new way of preventing and treating hyperuricemia and its complications.NEW & NOTEWORTHY Hyperuricemia is associated with many metabolic diseases. However, the underlying mechanism remains unknown. We constructed a hyperuricemic mouse model to explore the relationship between intestinal dysbiosis and metabolic disorder caused by hyperuricemia.


Assuntos
Hiperuricemia/patologia , Absorção Intestinal , Animais , Disbiose , Microbioma Gastrointestinal , Hiperuricemia/microbiologia , Imunidade Inata , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Permeabilidade , Fator de Necrose Tumoral alfa/metabolismo
7.
J Am Chem Soc ; 140(40): 13097-13102, 2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30212199

RESUMO

Realizing high thermoelectric performance requires high electrical transport properties and low thermal conductivity, which are essentially determined by balancing the interdependent controversy of carrier mobility, effective mass, and lattice thermal conductivity. Here, we observed an electronic band inversion (approaching topological insulating states) in Sn and Se co-alloyed PbTe, resulting in optimizing effective mass and carrier mobility. The Sn alloying in PbTe(Se) can narrow its band gap due to band inversion and induce a sharper conduction band (equals to lower carrier mass), which further facilitates high carrier mobility, ∼251 cm2 V-1 s-1 in Pb0.89Sn0.11Te0.89Se0.11 at room temperature, thus leading to a high power factor. Meanwhile, we found that the lattice thermal conductivity κl can be reduced from ∼0.77 Wm-1 K-1 in PbTe to ∼0.45 Wm-1 K-1 in (Pb0.91Sn0.09)(Te0.91Se0.09) by producing point defects via Sn and Se co-alloying. Coupling reducing lattice thermal conductivity with integration of optimizing effective mass and carrier mobility by  means of electronic band inversion, we obtained a maximum ZT value ∼1.4 at 773 K in n-type (Pb0.93Sn0.07)(Te0.93Se0.07).

8.
RSC Adv ; 14(1): 463-477, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38173595

RESUMO

In this study, using density functional and Boltzmann transport theories, we systematically investigated the effects of tensile and compressive strains on the elastic properties, phonon dispersion relation, electronic structure, and transport properties of the half-Heusler compound BiBaK. We calculated the elastic constants and phonon dispersion curves for BiBaK, which demonstrated its mechanical and thermodynamic stability, respectively, under different isotropic strains. Further, calculations showed that the electronic structure and energy bandgap of BiBaK changed with the application of isotropic strain. A high power factor and low thermal conductivity are key to improving the performance of thermoelectric materials. The figure of merit of BiBaK is 0.6 when it is unstrained and reaches a maximum value of 0.93 at -9% compressive strain and a temperature of 1200 K, indicating that under isotropic compressive strain, BiBaK compounds are efficient thermoelectric materials for high-temperature applications.

9.
RSC Adv ; 13(17): 11513-11524, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37063731

RESUMO

In this study, the full potential linearization enhanced plane wave method in density functional theory is used. Additionally, the structure, mechanical, and thermoelectric properties of half-Heusler compounds RhBiX (X = Ti, Zr, Hf) are investigated for the first time. The indirect semiconductors RhBiTi and RhBiZr have 0.89 and 1.06 eV bandgap energies, respectively. In contrast, RhBiHf is a direct bandgap semiconductor with a bandgap energy of 0.33 eV. The thermoelectric parameters such as Seebeck coefficient, power factor, electronic conductivity, lattice thermal conductivity, electronic thermal conductivity, and figure of merit ZT, are studied with the semi-classical Boltzmann transport theory. When T = 300 K, RhBiTi, RhBiZr, and RhBiHf show small lattice thermal conductivities, i.e., 10.60, 10.15, and 7.71 W mK-1, respectively, which are consistent with related other studies. The maximum ZT values of RhBiTi, RhBiZr, and RhBiXHf are 0.91, 0.94, and 0.79 at 900 K, respectively. Furthermore, we observed that RhBiX (X = Ti, Zr, Hf) alloy is a thermoelectric material with great potential.

10.
Neural Netw ; 157: 65-76, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36334540

RESUMO

Heterogeneous information network embedding aims to learn low-dimensional node vectors in heterogeneous information networks (HINs), concerning not only structural information but also heterogeneity of diverse node and relation types. Most existing HIN embedding models mainly rely on metapath to define composite relations between node pairs and thus extract substructures from the original HIN. However, due to the pairwise structure of metapath, these models fail to capture the high-order relations (such as "Multiple authors co-authoring a paper") implicitly contained in HINs. To tackle the limitation, this paper proposes a Metapath-aware HyperGraph Transformer (Meta-HGT) for node embedding in HINs. Meta-HGT first extends metapath to guide the high-order relation extraction from original HIN and constructs multiple metapath based hypergraphs with diverse composite semantics. Then, Meta-HGT learns the latent node and hyperedge embeddings in each metapath based hypergraph through Meta-HGT layers. Each layer consists of two types of components, i.e., intra-hyperedge aggregation and inter-hyperedge aggregation, in which a novel type-dependent attention mechanism is proposed for node and hyperedge feature aggregation. Finally, it fuses multiple node embeddings learned from different metapath based hypergraphs via a semantic attention layer and generates the final node embeddings. Extensive experiments have been conducted on three HIN benchmarks for node classification. The results demonstrate that Meta-HGT achieves state-of-the-art performance on all three datasets.


Assuntos
Aprendizagem , Semântica , Benchmarking , Serviços de Informação
11.
Nanoscale ; 15(29): 12340-12347, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37436124

RESUMO

Excellent magnetic properties at room temperature are crucial for the application of ferromagnets in spintronic and topological quantum devices. Using first-principles calculations and atomistic spin model simulations, we investigate the temperature-dependent magnetic properties of the Janus monolayer Fe2XY (X, Y = I, Br, Cl; X ≠ Y), as well as the effects of different magnetic interactions within the next-nearest-neighbor shell on the Curie temperature (TC). A large isotropic exchange interaction between one Fe atom and its next-nearest-neighbor counterparts can significantly increase the TC, while an antisymmetric exchange interaction decreases it. More importantly, we employ the temperature rescaling method, which can obtain temperature-dependent magnetic properties quantitatively consistent with experimental values, and find that the effective uniaxial anisotropy constant and coercive field decrease with increasing temperature. Moreover, at room temperature, Fe2IY is a rectangular-loop magnetic material with a giant coercive field up to ∼8 T, demonstrating its potential for application in room-temperature memory devices. Our findings can advance the application of these Janus monolayers in room-temperature spintronic devices and through heat-assisted techniques.

12.
PLoS One ; 18(12): e0293471, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38127853

RESUMO

Nitrogen (N) and rhizosphere pH are the two main factors restricting the growth of winter wheat (Triticum aestivum L.) in North China Plain. Soil nutrient availability is affected by soil acidity and alkalinity. In order to understand the effect of rhizosphere pH value on wheat nitrogen metabolism and the response of wheat growth to pH value at seedling stage, winter wheat varieties 'Aikang 58' (AK58) and 'Bainong 4199' (BN4199) were tested in hydroponics under three pH treatments (pH = 4.0, 6.5, and 9.0). The results showed that the accumulation of dry matter in root and above ground under pH 4.0 and pH 9.0 treatments was lower than that under pH 6.5 treatments, and the root/shoot ratio increased with the increase of pH value. Regardless of pH value, 'BN4199' had higher root dry weight, root length, root surface area, root activity and root tip than 'AK58'. Therefore, wheat that is tolerant to extreme pH is able to adapt to the acid-base environment by changing root characteristics. At pH 4.0, the net H+ outflow rate of wheat roots was significantly lower than that of the control group, and the net NO3- flux of wheat roots was also low. The net H+ outflow occurred at pH 6.5 and 9.0, and at the same time, the net NO3- flux of roots also increased, and both increased with the increase of pH. The activity of nitrate reductase (NR) in stem of pH 9.0 treatment was significantly higher than that of other treatments, while the activity of glutamine synthetase (GS) in root and stem of pH 6.5 treatment was significantly higher than that of other treatments. Under pH 4.0 and pH 9.0 treatments, the activities of NR and GS in 'BN4199' were higher than those in 'AK58', The root respiration of 'BN4199' was significantly higher than that of 'AK58' under pH 4.0 and pH 9.0 treatment, and 'BN4199' had higher NO3- net flux, key enzyme activity of root nitrogen metabolism and root respiration. Therefore, we believe that 'BN4199' has strong resistance ability to extreme pH stress, and high root/shoot ratio and strong root respiration can be used as important indicators for wheat variety screening adapted to the alkaline environment at the seedling stage.


Assuntos
Plântula , Triticum , Plântula/metabolismo , Nitrogênio/metabolismo , Força Próton-Motriz , Nitrato Redutase/metabolismo , Glutamato-Amônia Ligase/metabolismo , Solo
13.
J Chin Med Assoc ; 86(12): 1066-1073, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37792994

RESUMO

BACKGROUND: Previous studies on polymicrobial Pseudomonas aeruginosa bloodstream infections (Pa-BSIs) are dated, and it is necessary to reanalyze polymicrobial Pa-BSIs. The aim of this study was to investigate clinical characteristics and risk factors for polymicrobial Pa-BSI in comparison with monomicrobial Pa-BSI. METHODS: A double-center retrospective observational study was performed between January 1, 2013 and June 30, 2022, in two tertiary hospitals. All patients with Pa-BSI were enrolled, and their clinical data were collected by reviewing electronic medical records. RESULTS: A total of 278 patients with Pa-BSI were enrolled, including 77 patients (27.7%) with polymicrobial Pa-BSI. Compared with monomicrobial Pa-BSI, the main source of polymicrobial Pa-BSI was pneumonia (49.4% vs 31.3%, p < 0.01), whereas the main source of monomicrobial Pa-BSI was primary BSIs (21.9% vs 2.6%, p = 0.04). In multivariate analysis, a history of cerebrovascular accident (CVA) (adjusted odds ratio [OR], 3.62; 95% CI, 1.46-8.92) was independently associated with polymicrobial Pa-BSI. Primary BSI was associated with monomicrobial Pa-BSI (OR, 0.08; 95% CI, 0.02-0.38). Patients with polymicrobial Pa-BSI had a longer intensive care unit (ICU) length of stay after onset of BSI than those with monomicrobial Pa-BSI (2 [2, 16] vs 13 [3.75, 29], p = 0.02). CONCLUSION: Patients with Pa-BSI and the presence of CVA need to be alert to the possibility of polymicrobial BSI occurrence. Prolonged ICU stay and pneumonia as a source of BSI warrant clinician attention for polymicrobial Pa-BSI, and primary BSIs are likely associated with monomicrobial BSIs.


Assuntos
Bacteriemia , Pneumonia , Humanos , Pseudomonas aeruginosa , Bacteriemia/complicações , Bacteriemia/epidemiologia , Estudos Retrospectivos , Fatores de Risco
14.
Front Plant Sci ; 14: 1253536, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38192698

RESUMO

Real-time monitoring of canopy chlorophyll content is significant in understanding crop growth status and guiding precision agricultural management. Remote sensing methods have demonstrated great potential in this regard. However, the spatiotemporal heterogeneity of chlorophyll content within crop canopies poses challenges to the accuracy and stability of remote sensing estimation models. Hence, this study aimed to develop a novel method for estimating canopy chlorophyll content (represented by SPAD values) in maize (Zea mays L.) canopies. Firstly, we investigated the spatiotemporal distribution patterns of maize canopy SPAD values under varying nitrogen application rates and different growth stages. The results revealed a non-uniform, "bell-shaped" curve distribution of maize canopy SPAD values in the vertical direction. Nitrogen application significantly influenced the distribution structure of SPAD values within the canopy. Secondly, we achieved satisfactory results by fitting the Lorentz peak distribution function to the SPAD values of different leaf positions in maize. The fitting performance, evaluated using R2 and RMSE, ranged from 0.69 to 0.98 and 0.45 to 3.59, respectively, for the year 2021, and from 0.69 to 0.77 and 2.38 to 6.51, respectively, for the year 2022.Finally, based on the correlation between canopy SPAD values and vegetation indices (VIs) at different growth stages, we identified the sensitive leaf positions for the selected CCCI (Canopy Chlorophyll Index) in each growth stage. The 6th (r = 0.662), 4th (r = 0.816), 12th (r = 0.722), and 12th (r = 0.874) leaf positions exhibited the highest correlations. Compared to the estimation model using canopy wide SPAD values, the model based on sensitive leaf positions showed improved accuracy, with increases of 34%, 3%, 20%, and 3% for each growth stage, respectively. In conclusion, the findings of this study contribute to the enhancement of chlorophyll content estimation models in crop canopies and provide valuable insights for the integration of crop growth models with remote sensing methods.

15.
Zhonghua Yi Shi Za Zhi ; 52(2): 111-115, 2022 Mar 28.
Artigo em Zh | MEDLINE | ID: mdl-35570347

RESUMO

Wan's gynecology and obstetrics (Wan Shi Nv Ke), collected by the library of China Academy of Chinese Medical Sciences, was examined with the field method. It was found some issues existed both in the recording and description of Wan's gynecology and obstetrics (Wan Shi Nv Ke) collected by the library of China Academy of Chinese Medical Sciences in the electronic catalogue of ancient books and in the General catalogue of ancient books of traditional Chinese Medicine (Zhong Guo Zhong Yi Gu Ji Zong Mu), in terms of the same version with different registration, wrong publication time, some contents missed in publication, and the version actually not collected.


Assuntos
Ginecologia , Obstetrícia , Livros , China , Feminino , Humanos , Medicina Tradicional Chinesa , Gravidez
16.
Phys Rev Lett ; 104(4): 047002, 2010 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-20366732

RESUMO

The electronic structures of FeAs compounds are sensitive to FeAs bonding, which is described unsuccessfully by the local density approximation (LDA). Treating the multiorbital fluctuations from ab inito LDA+Gutzwiller method, we can now predict the correct FeAs bond length and bonding strength, which will explain the observed "soft phonon." The bands are narrowed by a factor of 2 from their LDA widths. The d{3z{2}-r{2}} orbital is pushed up to cross the Fermi level, forming a three-dimensional Fermi surface, which reduces the anisotropy. The interorbital Hund's coupling J rather than U plays a crucial role in obtaining these results.

17.
Research (Wash D C) ; 2020: 4084532, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33623904

RESUMO

PbS is a latent substitute of PbTe thermoelectric materials, which is on account of its superiority in low cost and earth abundance. Here, the thermoelectric transport properties of p-type PbS by doping alkali metals (Na and Li) are investigated and it is verified that Li is a more effective dopant than Na. By introducing Li, the electrical and thermal transport properties were optimized collectively. The electrical transport properties were boosted remarkably via adjusting carrier concentration, and the maximum power factor (PFmax) of ~11.5 µW/cmK2 and average power factor (PFave) ~9.9 µW/cmK2 between 423 and 730 K in Pb0.99Li0.01S were achieved, which are much higher than those (~9.5 and ~7.7 µW/cmK2) of Pb0.99Na0.01S. Doping Li and Na can weaken the lattice thermal conductivity effectively. Combining the enlarged PF with suppressed total thermal conductivity, a maximum ZT ~0.5 at 730 K and a large average ZT ~0.4 at 423-730 K were obtained in p-type Pb0.99Li0.01S, which are higher than ~0.4 and ~0.3 in p-type Pb0.99Na0.01S, respectively.

18.
PeerJ ; 8: e8664, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32185104

RESUMO

Some studies on the hyperuricemia (HUA) have focused on intestinal bacteria. To better understand the correlation between gut microbiota and HUA, we established a HUA rat model with high-purine diet, and used 16S rRNA genes sequencing to analyze gut microbiota changes in HUA rats. To analyze the potential role played by gut microbiota in HUA, we altered the gut microbiota of HUA rats with antibiotics, and compared the degree of uric acid elevation between HUA and antibiotic-fed HUA rats (Ab+HUA). Finally, we established a recipient rat model, in which we transplanted fecal microbiota of HUA and normal rats into recipient rats. Three weeks later, we compared the uric acid content of recipient rats. As a result, the diversity and abundance of the gut microbiota had changed in HUA rats. The Ab-fed HUA rats had significantly lower uric acid content compared to the HUA rats, and gut microbiota from HUA rats increased uric acid content of recipient rats. The genera Vallitalea, Christensenella and Insolitispirillum may associate with HUA. Our findings highlight the association between gut microbiota and HUA, and the potential role played by gut microbiota in HUA. We hope that this finding will promote the isolation and culture of HUA-related bacteria and orient HUA-related studies from being correlational to mechanistic. These steps will therefore make it possible for us to treat HUA using gut microbiota as the target.

19.
J Phys Condens Matter ; 21(26): 265602, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21828475

RESUMO

The Jahn-Teller (JT) distortion induced orbital order and optical conductivity in SrRuO(3) and CaRuO(3) are investigated by first-principles calculations. The total energy and optical conductivity of all the spin ordering states of SrRuO(3) and CaRuO(3) are calculated in the LDA+U scheme with U(eff) = 2.5 eV. The down-spin t(2g) of Ru show antiferromagnetic-like orbital order in the a-b plane. We observe a d-d transition peak at an energy of about 1.0 eV in the calculated optical conductivity and analyze the reason for it not being observed in previous experiments.

20.
J Phys Condens Matter ; 31(29): 295501, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30965305

RESUMO

ThTaN3 is known as a rare cubic perovskite nitride topological crystalline insulator (TCI). Here, we propose, using first-principles calculations, that compressive uniaxial (0 0 1) strained ThTaN3 can host a three dimensional nodal-chain semimetal state when spin-orbit coupling (SOC) is ignored. When SOC is turned on, the nodal-chain is gapped out, resulting in a pair of type-II Dirac points as protected by C 4 crystal symmetry. Intriguingly, under an increasing compressive uniaxial (0 0 1) strain, a new pair of type-I Dirac points emerges, realizing a novel Dirac semimetal that hosts both type-I and type-II Dirac points in momentum space. The electronic structures of the projected surfaces are also discussed, and the unique Fermi arcs are observed. Our results make ThTaN3 a promising platform for experimental realization of multiple types of Dirac fermions in a single material system.

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