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1.
Phys Chem Chem Phys ; 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34651633

RESUMO

GeTe has become a high-performance thermoelectric material with a figure of merit (ZT) over two through alloying and band engineering strategies. Yet, the question on how to effectively engineer the electronic band structure of GeTe toward achieving a better thermoelectric performance still cannot be clearly answered, and its underlying physics has not been well understood. Here, we manipulate the lattice structure of GeTe via modifying the lattice parameters, interaxial angles and reciprocal displacements, and investigate their influence on the electronic band structure and thermoelectric properties using first-principles calculations. The calculation results show that the reciprocal displacement directly manipulates the energy level of the L-band and the Z-band, resulting in an indirect-direct transition of the band gap and a strong Rashba effect. Modifications of lattice parameters and interaxial angles can affect band gaps, band convergence and density of states, which are crucial to determining thermoelectric performance. This work performs a systematic study on how the lattice structure manipulation influences the electronic band structure and thermoelectric properties of GeTe, and can provide a clear route to further enhance its ZT.

2.
Appl Opt ; 60(23): 6869-6877, 2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613168

RESUMO

The third-generation wide bandgap semiconductor GaN currently occupies a hot spot in the fields of high-power electronics and optoelectronics. Fully exploring its optical and optoelectronic characteristics is of great significance. Here, we provide a systematic study on the temperature-dependent dielectric functions of GaN grown by metal-organic chemical vapor deposition in the spectral range of 0.73-5.90 eV via spectroscopic ellipsometry experiments and first-principles calculations. Ellipsometric measurements identify two typical absorption peaks that originate from the excitonic and phonon-assisted indirect absorption process, respectively. To explore the underlying physics, we perform first-principles calculations using the independent-particle approximation, model Bethe-Salpeter equation (mBSE), and phonon-assisted indirect absorption process (Inabs). In comparison with ellipsometric measurements, the mBSE calculation determines the absorption peak contributed by the many-body excitonic effect, while the Inabs calculation successfully predicts the second absorption peak. When heating the crystal, it observes the redshift and weakening of absorption peaks, intrinsically due to the nontrivial electron-phonon interaction as lattice vibration strengthens. While doping GaN with Fe or Si elements, the introduced free carriers modify the electronic interband transition. As the temperature increases, more free carriers are excited, and the temperature influence on the absorption peak is more significant than that of the undoped one. This work fully explores the physical origins of the temperature and doping effect on UV-Vis dielectric functions of GaN, aiming to promote its application in the fields of high-power electronic devices.

3.
ACS Appl Mater Interfaces ; 13(39): 46451-46463, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34570459

RESUMO

Light-driven endogenous water oxidation has been considered as an attractive and desirable way to obtain O2 and reactive oxygen species (ROS) in the hypoxic tumor microenvironment. However, the use of a second near-infrared (NIR-II) light to achieve endogenous H2O oxidation to alleviate tumor hypoxia and realize deep hypoxic tumor phototherapy is still a challenge. Herein, novel plasmonic Ag-AgCl@Au core-shell nanomushrooms (NMs) were synthesized by the selective photodeposition of plasmonic Au at the bulge sites of the Ag-AgCl nanocubes (NCs) under visible light irradiation. Upon NIR-II light irradiation, the resulting Ag-AgCl@Au NMs could oxidize endogenous H2O to produce O2 to alleviate tumor hypoxia. Almost synchronously, O2 could react with electrons on the conduction band of the AgCl core to generate superoxide radicals (O2•-)for photodynamic therapy. Moreover, Ag-AgCl@Au NMs with an excellent photothermal performance could further promote the phototherapy effect. In vitro and in vivo experimental results show that the resulting Ag-AgCl@Au NMs could significantly improve tumor hypoxia and enhance phototherapy against a hypoxic tumor. The present study provides a new strategy to design H2O-activatable, O2- and ROS-evolving NIR II light-response nanoagents for the highly efficient and synergistic treatment of deep O2-deprived tumor tissue.

4.
Biofabrication ; 13(4)2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34488209

RESUMO

Tissue engineering has attracted attention worldwide because of its application in regenerative medicine, drug screening, and cultured meat. Numerous biofabrication techniques for producing tissues have been developed, including various scaffold and printing methods. Here, we have proposed a novel tissue engineering method using a net metal mould without the use of a scaffold. Briefly, normal human dermal fibroblasts seeded on a dimple plate were subjected to static culture technique for several days to form spheroids. Spheroids of diameter ⩾200µm were poured into a net-shaped mould of gap ⩽100µm and subjected to shake-cultivation for several weeks, facilitating their fusion to form a three-dimensional (3D) tissue. Through this study, we successfully constructed a scaffold-free 3D tissue having strength that can be easily manipulated, which was difficult to construct using conventional tissue engineering methods. We also investigated the viability of the 3D tissue and found that the condition of the tissues was completely different depending on the culture media used. Collectively, this method allows scaffold-free culture of 3D tissues of unprecedented thickness, and may contribute largely to next-generation tissue engineering products.

5.
Opt Lett ; 46(17): 4244-4247, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469985

RESUMO

Perovskite SrTiO3 has emerged as a relevant technological material for nano-photonics that confines light to subdiffraction geometry with remarkably wide spectral tunability. Yet, the influence of lattice vibrations on its surface phonon polaritons (SPhPs) and localized surface phonon resonances (LSPhRs) receives little attention, and the underlying physics still remains elusive. Here, we apply spectroscopic ellipsometry (SE) experiments and multiscale simulations spanning from first-principles to finite-difference time-domain (FDTD), and investigate the temperature influence on infrared dielectric functions, SPhPs and LSPhRs of SrTiO3. SE measurements find that the width of the Reststrahlen band lying between transverse and longitudinal oxygen-related optical phonons changes slightly, but infrared dielectric functions vary significantly as temperature increases. First-principles calculations confirm the coupling of the motion of oxygen atoms to incident photons, forming quasiparticles of SPhPs. FDTD simulations show that strong LSPhRs exist at 250 K in the SrTiO3 nanodisks but dissipate as lattice vibration strengthens, mainly due to the reduced phonon relaxation lifetime. This work reveals the underlying physics of temperature influence on SPhPs and LSPhRs of SrTiO3 and helps explore its potential applications as photonic resonators at high temperatures.

6.
Ann Palliat Med ; 10(8): 9304-9308, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488417

RESUMO

Hypercalcemia is a clinical emergency which can cause hypercalcemic crisis and even endanger patients' lives. The increase of serum calcium concentration is caused by the redistribution of calcium in bone and the inhibition of parathyroid secretion, which is known as non-parathyroid hypercalcemia. In this report, we presented a rare case of non-parathyroid hypercalcemia during lactation in order to optimize the diagnosis and treatment of this condition. A 27-year-old female patient was admitted to Wuxi People's Hospital on July 11, 2019 due to "fatigue, anorexia, and pain in both knees for half a month". The patient had fatigue and discomfort, accompanied by pain in both knees without obvious inducement. At the same time, the patient had decreased food intake. In the past 3 days, the symptoms worsened, accompanied by limb numbness. The serum calcium level was increased and the parathyroid hormone (PTH) level was decreased. The patient was diagnosed with hypercalcemia, and was treated with calcitonin and lactation termination. The knee pain disappeared and serum calcium returned to normal during a 2-week follow-up. To conclude, the correlation between hypercalcemia and lactation needs to be considered for non-parathyroid hypercalcemia during lactation. After excluding other possible causes, lactation termination therapy may be an effective therapeutic strategy for non-parathyroid hypercalcemia caused by excessive lactation.


Assuntos
Hipercalcemia , Adulto , Cálcio , Feminino , Humanos , Hipercalcemia/etiologia , Lactação , Dor , Hormônio Paratireóideo
7.
Front Immunol ; 12: 704965, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456915

RESUMO

Interferon-induced transmembrane protein 3 (IFITM3) is an interferon-induced membrane protein, which has been identified as a functional gene in multiple human cancers. The role of IFITM3 in cancer has been preliminarily summarized, but its relationship to antitumor immunity is still unclear. A pancancer analysis was conducted to investigate the expression pattern and immunological role of IFITM3 based on transcriptomic data downloaded from The Cancer Genome Atlas (TCGA) database. Next, correlations between IFITM3 and immunological features in the bladder cancer (BLCA) tumor microenvironment (TME) were assessed. In addition, the role of IFITM3 in estimating the clinical characteristics and the response to various therapies in BLCA was also evaluated. These results were next confirmed in the IMvigor210 cohort and a recruited cohort. In addition, correlations between IFITM3 and emerging immunobiomarkers, such as microbiota and N6-methyladenosine (m6A) genes, were assessed. IFITM3 was enhanced in most tumor tissues in comparison with adjacent tissues. IFITM3 was positively correlated with immunomodulators, tumor-infiltrating immune cells (TIICs), cancer immunity cycles, and inhibitory immune checkpoints. In addition, IFITM3 was associated with an inflamed phenotype and several established molecular subtypes. IFITM3 expression also predicted a notably higher response to chemotherapy, anti-EGFR therapy, and immunotherapy but a low response to anti-ERBB2, anti-ERBB4, and antiangiogenic therapy. In addition, IFITM3 was correlated with immune-related microbiota and m6A genes. In addition to BLCA, IFITM3 is expected to be a marker of high immunogenicity in most human cancers. In conclusion, IFITM3 expression can be used to identify immuno-hot tumors in most cancers, and IFITM3 may be a promising pancancer biomarker to estimate the immunological features of tumors.

8.
Microbiol Resour Announc ; 10(28): e0062721, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264119

RESUMO

Atopobiaceae bacterium strain P1 (Actinobacteria, Coriobacteriales) was isolated from mouse feces. Here, we report the complete genome sequence of this strain, which has a total size of 2,028,478 bp and a G+C content of 58.6%.

9.
Sci Adv ; 7(30)2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34290097

RESUMO

The deuterium versus hydrogen (D/H) isotopic ratios are important to understand the source of water on Earth and other terrestrial planets. However, the determinations of D/H ratios suggest a hydrogen isotopic diversity in the planetary objects of the solar system. Photochemistry has been suggested as one source of this isotope heterogeneity. Here, we have revealed the photodissociation features of the water isotopologue (HOD) at λ = 120.8 to 121.7 nm. The results show different quantum state populations of OH and OD fragments from HOD photodissociation, suggesting strong isotope effect. The branching ratios of H + OD and D + OH channels display large isotopic fractionation, with ratios of 0.70 ± 0.10 at 121.08 nm and 0.49 ± 0.10 at 121.6 nm. Because water is abundant in the solar nebula, photodissociation of HOD should be an alternative source of the D/H isotope heterogeneity. This isotope effect must be considered in the photochemical models.

11.
J Fish Dis ; 44(10): 1609-1617, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34192354

RESUMO

The expression of herpesvirus genes during infection of tissue culture cells can be classified into three main classes: immediate-early (IE), early and late. The transcriptional regulation of herpesvirus IE genes is a critical regulatory step in the initiation of viral infection, with their regulation differing from that of early and late genes. Herein, we report that an IE gene (ORF3) promoter in channel catfish virus (CCV, Ictalurid herpesvirus 1) can be activated regardless of the presence or absence of CCV infection, indicating that the ORF3 promoter is efficiently driven by host-cell transcription factors in a viral infection-independent manner. The analysis of truncated promoter activity suggested that several transcription elements play a role in activating the ORF3 promoter, with the key cis-elements seemingly located in the flanking sequence of the start codon ATG. We further found that this flanking sequence contained multiple AT-rich sequences, and systematic mutational analyses showed that these AT-rich sequences affected normal transcription levels of the ORF3 promoter. To summarize, multiple AT-rich domains, representing the novel architecture of IE gene promoters in Ictalurid herpesvirus 1, serve as a cis-element for ORF3 transcription.

12.
Microbiol Resour Announc ; 10(19)2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986097

RESUMO

Adlercreutzia equolifaciens subsp. celatus DSM 18785 was isolated from the cecal contents of a rat and is an obligately anaerobic equol-producing bacterium. Here, we report the finished and annotated genome sequence of this organism, which has a genome size of 2,929,991 bp and a G+C content of 63.2%.

13.
Nat Commun ; 12(1): 2476, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931653

RESUMO

The provenance of oxygen on the Earth and other planets in the Solar System is a fundamental issue. It has been widely accepted that the only prebiotic pathway to produce oxygen in the Earth's primitive atmosphere was via vacuum ultraviolet (VUV) photodissociation of CO2 and subsequent two O atom recombination. Here, we provide experimental evidence of three-body dissociation (TBD) of H2O to produce O atoms in both 1D and 3P states upon VUV excitation using a tunable VUV free electron laser. Experimental results show that the TBD is the dominant pathway in the VUV H2O photochemistry at wavelengths between 90 and 107.4 nm. The relative abundance of water in the interstellar space with its exposure to the intense VUV radiation suggests that the TBD of H2O and subsequent O atom recombination should be an important prebiotic O2-production, which may need to be incorporated into interstellar photochemical models.

14.
J Phys Chem A ; 125(17): 3622-3630, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33891426

RESUMO

Photodissociation dynamics of H2O via the E'1B2 state were studied using the high-resolution H atom photofragment translational spectroscopy method, in combination with the tunable vacuum ultraviolet free electron laser (VUV FEL). The measured translational energy spectra allow us to determine the respective quantum state population distributions for the nascent OH(X2Π) and OH(A2Σ+) photofragments. Analyses of the quantum state population distributions show both the ground and electronically excited OH fragments to be formed with moderate vibrational excitation but with highly rotational excitation. Unlike the dissociation via the lower-lying electronic states, where OH(X) is the major fragment, the OH(A) products are predominant via the E' state. These products are mainly ascribed to a fast dissociation on the B̃1A1 state surface after nonadiabatic transitions from the initial excited E' state to the B̃ state. Meanwhile, another dissociation pathway from the E' state to the 1B2 3pb2 state, followed by coupling to the 1A2 3pb2 state, is also observed, which yields the OH(X) + H and O(3P) + 2H products.

15.
Cancer Cell Int ; 21(1): 162, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691685

RESUMO

BACKGROUND: Patients with type 2 diabetes mellitus (T2DM) have an increased risk of suffering from various malignancies. This study aimed to identify specific biomarkers that can detect lung adenocarcinoma (LAC) in T2DM patients for the early diagnosis of LAC. METHODS: The clinical information of hospitalized T2DM patients diagnosed with various cancers was collected by reviewing medical records in Wuxi People's Hospital Affiliated to Nanjing Medical University from January 1, 2015, to June 30, 2020. To discover diagnostic biomarkers for early-stage LAC in the T2DM population, 20 samples obtained from 5 healthy controls, 5 T2DM patients, 5 LAC patients and 5 T2DM patients with LAC (T2DM + LAC) were subjected to sequential windowed acquisition of all theoretical fragment ion mass spectrum (SWATH-MS) analysis to identify specific differentially-expressed proteins (DEPs) for LAC in patients with T2DM. Then, these results were validated by parallel reaction monitoring MS (PRM-MS) and ELISA analyses. RESULTS: Lung cancer was the most common malignant tumor in patients with T2DM, and LAC accounted for the majority of cases. Using SWATH-MS analysis, we found 13 proteins to be unique in T2DM patients with early LAC. Two serum proteins were further validated by PRM-MS analysis, namely, pregnancy-zone protein (PZP) and insulin-like growth factor binding protein 3 (IGFBP3). Furthermore, the diagnostic values of these proteins were validated by ELISA, and PZP was validated as a novel serum biomarker for screening LAC in T2DM patients. CONCLUSIONS: Our findings indicated that PZP could be used as a novel serum biomarker for the identification of LAC in T2DM patients, which will enhance auxiliary diagnosis and assist in the selection of surgical treatment at an early stage.

16.
J Phys Chem Lett ; 12(9): 2259-2265, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33636082

RESUMO

Elucidating the dynamic couplings of hydrogen bonds remains an important and challenging goal for spectroscopic studies of bulk systems, because their vibrational signatures are masked by the collective effects of the fluctuation of many hydrogen bonds. Here we utilize size-selected infrared spectroscopy based on a tunable vacuum ultraviolet free electron laser to unmask the vibrational signatures for the dynamic couplings in neutral trimethylamine-water and trimethylamine-methanol complexes, as microscopic models with only one single hydrogen bond holding two molecules. Surprisingly broad progression of OH stretching peaks with distinct intensity modulation over ∼700 cm-1 is observed for trimethylamine-water, while the dramatic reduction of this progression in the trimethylamine-methanol spectrum offers direct experimental evidence for the dynamic couplings. State-of-the-art quantum mechanical calculations reveal that such dynamic couplings are originated from strong Fermi resonance between the stretches of hydrogen-bonded OH and several motions of the solvent water/methanol, such as translation, rocking, and bending, which are significant in various solvated complexes commonly found in atmospheric and biological systems.

17.
PeerJ ; 9: e10800, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33604184

RESUMO

Objective: To investigate serum intestinal fatty acid-binding protein (I-FABP) in two groups of patients with different duration of hyperglycemia in a cross-sectional study. Materials and Methods: In the present study, a total of 280 individuals (158 outpatients and 122 inpatients) suffering from hyperglycemia were recruited between May and September 2019. The clinical information of all participants was collected from the hospital information system, including the duration of hyperglycemia, age, gender, hemoglobin A1c (HbA1c), 75-g oral glucose tolerance test including fasting plasma glucose (FPG), 2-hour plasma glucose (2hPG), fasting C-peptide (FC-pep), 2-hour C-peptide (2hC-pep), fasting insulin (FIns), and 2-hour insulin (2hIns). In addition, the morbidity of diabetic complications (retinopathy, neuropathy, and nephropathy) in the inpatient group was determined. Furthermore, the difference between 2hPG and FPG (ΔPG), the difference between 2hC-pep and FC-pep (ΔC-pep), and the difference between 2hIns and FIns (ΔIns) were calculated. The level of serum I-FABP, a biomarker of intestinal barrier (IB) dysfunction, was estimated by an enzyme-linked immunosorbent assay. Results: For the outpatient group, the median duration of hyperglycemia was less than a year; the serum I-FABP level was positively correlated with age (R = 0.299, P < 0.001). For the inpatient group, the median duration of hyperglycemia was ten years; correlation analysis showed that the serum I-FABP level was positively associated with age and ΔPG (R = 0.286, P = 0.001; R = 0.250, P = 0.006, respectively) while negatively associated with FC-pep and 2hC-pep (R =  - 0.304, P = 0.001; R =  - 0.241, P = 0.008, respectively); multiple linear regression analysis showed that the serum I-FABP level was positively associated with the duration of hyperglycemia (ß = 0.362, P < 0.001); moreover, patients with retinopathy had a significantly higher I-FABP level than those without retinopathy (P = 0.001). Conclusions: In the outpatients whose duration of hyperglycemia was less than a year, the serum I-FABP level was positively associated with age. In the inpatients with different courses of diabetes, the serum I-FABP level was positively associated with the duration of hyperglycemia and glycemic variability but negatively associated with islet beta-cell function; moreover, the serum I-FABP level was higher in patients with retinopathy than in those without retinopathy, suggesting that the IB dysfunction got worse with the progression of diabetes.

18.
J Phys Chem Lett ; 12(3): 1012-1017, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33470826

RESUMO

Neutral titanium-metal carbonyl complexes with the chemical formula Ti(CO)n (n = 4-7) are produced in the gas phase by the reactions of titanium atoms with carbon monoxide in a pulsed laser vaporization-supersonic expansion source. Their infrared absorption spectra in the carbonyl stretching frequency region are measured by infrared plus vacuum ultraviolet (IR+VUV) two-color ionization spectroscopy based on a tunable VUV free electron laser. Infrared spectroscopy in conjunction with quantum chemical calculations confirm that all of these complexes have unexpected titanium ketenylidene OTiCCO(CO)n-2 structures. Bonding analysis indicates that the OTiCCO core structure can be described by the bonding interactions between a TiO+ cation in the doublet ground state and a doublet ground state of CCO-. The results reveal that the C-O bond breaking and C-C bond formation proceed efficiently in the reactions between laser-vaporized titanium atoms and carbon monoxide.

19.
J Phys Chem Lett ; 12(2): 844-849, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33427476

RESUMO

Carbon disulfide (CS2) is a typical triatomic molecule. Its photodissociation process has generally been assumed to proceed to CS and S primary products via single bond fission. However, recent theoretical calculations suggested that an exit channel to produce C + S2 should also be energetically accessible. Here, we report the direct experimental evidence for the C + S2 channel in CS2 photodissociation by using the velocity map ion imaging technique with two-photon UV and one-photon vacuum UV (VUV) excitations. The detection of the C (3P) products illustrates that the ground state and the electronically excited states of S2 coproducts are formed within highly excited vibrational states. The very weak anisotropic distributions indicate relatively slow dissociation processes. The possible dissociation mechanism involves molecular isomerization of CS2 to linear-CSS from the excited 1B2 (21Σ+) state via vibronic coupling with the 1Π state followed by an avoided crossing with the ground state surface. Our results imply that the S2 molecules observed in comets might be primarily formed in CS2 photodissociation.

20.
Phys Chem Chem Phys ; 22(48): 28086-28092, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33289745

RESUMO

The prototype phonon-liquid electron-crystal ß-Cu2Se has been ranked among the best thermoelectric material with its ultralow lattice thermal conductivity (κL). The atomic fluidity, harmonic approximation failure, and the existence of a large number of imaginary phonon modes hinder the atomistic analysis of phonon transport in ß-Cu2Se. Thus, the atomistic origins of its ultralow κL remain elusive. In this study, we present a self-consistent phonon (SCPH) calculation of the lattice dynamical properties of ß-Cu2Se by including quartic anharmonicity and stiffening imaginary phonon modes in the anharmonic phonon dispersion, aiming to unravel the atomistic origins of ultralow κL. Upon renormalizing harmonic phonon dispersion with quartic anharmonicity, those imaginary phonon modes arising from copper fluidity diminish as temperature increases and anharmonic phonon dispersions are obtained. By solving the Boltzmann transport equation within the relaxation time approximation (BTE-RTA), we predicted ultralow κL which demonstrated an overall agreement with previous experiments. After analyzing the harmonic as well as anharmonic phonon density of states, it was found that the inclusion of quartic anharmonicity induces the suppression of low-lying phonon modes, which coincides with the experimental observation of the selective breakdown of long-wave transverse acoustic phonons. However, for the propagative heat-carriers, the anharmonic scattering enhances and phonon relaxation lifetime decreases as temperature increases, leading to a further reduction of κL. This study provides an extra insight into the atomistic origins of ultralow κL in ß-Cu2Se from first-principles anharmonic force constants and helps engineer the lattice dynamical properties for better thermoelectric performance.

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