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1.
Stroke ; 55(5): 1339-1348, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38511314

RESUMO

BACKGROUND: Evaluating rupture risk in cerebral arteriovenous malformations currently lacks quantitative hemodynamic and angioarchitectural features necessary for predicting subsequent hemorrhage. We aimed to derive rupture-related hemodynamic and angioarchitectural features of arteriovenous malformations and construct an ensemble model for predicting subsequent hemorrhage. METHODS: This retrospective study included 3 data sets, as follows: training and test data sets comprising consecutive patients with untreated cerebral arteriovenous malformations who were admitted from January 2015 to June 2022 and a validation data set comprising patients with unruptured arteriovenous malformations who received conservative treatment between January 2009 and December 2014. We extracted rupture-related features and developed logistic regression (clinical features), decision tree (hemodynamic features), and support vector machine (angioarchitectural features) models. These 3 models were combined into an ensemble model using a weighted soft-voting strategy. The performance of the models in discriminating ruptured arteriovenous malformations and predicting subsequent hemorrhage was evaluated with confusion matrix-related metrics in the test and validation data sets. RESULTS: A total of 896 patients (mean±SD age, 28±14 years; 404 women) were evaluated, with 632, 158, and 106 patients in the training, test, and validation data sets, respectively. From the training set, 9 clinical, 10 hemodynamic, and 2912 pixel-based angioarchitectural features were extracted. A logistic regression model was built using 4 selected clinical features (age, nidus size, location, and venous aneurysm), whereas a decision-tree model was constructed from 4 hemodynamic features (outflow time, stasis index, cerebral blood flow, and outflow volume ratio). A support vector machine model was designed using 5 pixel-based angioarchitectural features. In the validation data set, the accuracy, sensitivity, specificity, and area under the curve of the ensemble model for predicting subsequent hemorrhages were 0.840, 0.889, 0.823, and 0.911, respectively. CONCLUSIONS: The ensemble model incorporating clinical, hemodynamic, and angioarchitectural features showed favorable performance in predicting subsequent hemorrhage of cerebral arteriovenous malformations.

2.
J Am Chem Soc ; 146(11): 7352-7362, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38447048

RESUMO

Knowledge of structure-property relationships in solids with intrinsic low thermal conductivity is crucial for fields such as thermoelectrics, thermal barrier coatings, and refractories. Herein, we propose a new "rigidness in softness" structural scheme for intrinsic low lattice thermal conductivity (κL), which embeds rigid clusters into the soft matrix to induce large lattice anharmonicity, and accordingly discover a new series of chalcogenides Pt3Bi4Q9 (Q = S, Se). Pt3Bi4S9-xSex (x = 3, 6) achieved an intrinsic ultralow κL down to 0.39 W/(m K) at 773 K, which is considerably low among the Bi chalcogenide thermoelectric materials. Pt3Bi4Q9 contains the rigid cubic [Pt6Q12]12- clusters embedded in the soft Bi-Q sublattice, involving multiple bonding interactions and vibration hierarchy. The hierarchical structure yields a large lattice anharmonicity with high Grüneisen parameters (γ) 1.97 of Pt3Bi4Q9, as verified by the effective scatter of low-lying optical phonons toward heat-carrying acoustic phonons. Consequently, the rigid-soft coupling significantly inhibits heat propagation, exhibiting low acoustic phonon frequencies (∼25 cm-1) and Debye temperatures (ΘD = 170.4 K) in Pt3Bi4Se9. Owing to the suppressed κL and considerable power factor (PF), the ZT value of Pt3Bi4S6Se3 can reach 0.56 at 773 K without heavy carrier doping, which is competitive among the pristine Bi chalcogenides. Theoretical calculations predicted a large potential for performance improvement via proper doping, indicating the great potential of this structure type for promising thermoelectric materials.

3.
Cancer ; 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353467

RESUMO

BACKGROUND: The objective of this study was to explore the abilities of atezolizumab plus chemotherapy in preventing brain metastases (BMs) among metastatic non-small cell lung cancer (NSCLC) without initial BMs, as well as the risk factors of BMs. METHODS: Individual patient data from three trials involving first-line atezolizumab for metastatic NSCLC (IMpower130, IMpower131, and IMpower150) were pooled. Among patients without baseline BMs and without epidermal growth factor receptor (EGFR) and/or anaplastic lymphoma kinase (ALK) mutations, those receiving atezolizumab + chemotherapy ± bevacizumab were classified as the atezolizumab plus chemotherapy group and those receiving placebo + chemotherapy ± bevacizumab were classified as the chemotherapy group. The cumulative incidences of BM (CI-BMs) between the two groups were compared. Other factors associated with the CI-BM were analyzed by Cox regression analyses. RESULTS: With a median follow-up of 17.6 months (range, 0.03-33.64 months), 74 (3.1%) of the 2380 enrolled patients developed BMs, including 50 (3.1%) and 24 (3.0%) in the atezolizumab plus chemotherapy group (n = 1589) and the chemotherapy group (n = 791), respectively. The CI-BMs at 6, 12, and 24 months were 1.7%, 2.8%, and 3.3%, respectively. After taking competing risk events into account, there was no significant difference in the CI-BMs between the two groups (p = .888). Nevertheless, the use of bevacizumab and the histology of nonsquamous NSCLC were found to be independently associated with the risk of BMs. CONCLUSIONS: In patients with metastatic EGFR/ALK wild-type NSCLC without baseline BMs, adding atezolizumab in the first-line treatment might not reduce the CI-BM. However, the administration of bevacizumab may reduce the risk of BMs.

4.
New Phytol ; 241(3): 1177-1192, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37985404

RESUMO

The locular gel, produced by the placenta, is important for fruit flavor and seed development in tomato. However, the mechanism underlying locule and placenta development is not fully understood yet. Here, we show that two SlARF transcription factors, SlARF8B and SlARF8A (SlARF8A/B), promote the development of locular and placenta tissues. The expression of both SlARF8A and SlARF8B is repressed by sly-microRNA167 (sly-miR167), allowing for the activation of auxin downstream genes. In slarf8a, slarf8b, and slarf8a/b mutants, the auxin (IAA) levels are decreased, whereas the levels of inactive IAA conjugates including IAA-Ala, IAA-Asp, and IAA-Glu are increased. We further find that SlARF8B directly inhibits the expression of SlGH3.4, an acyl acid amino synthetase that conjugates the amino acids to IAA. Disruption of such auxin balance by the increased expression of SlGH3.4 or SlGH3.2 results in defective locular and placental tissues. Taken together, our findings reveal an important regulatory module constituted by sly-miR167-SlARF8A/B-SlGH3.4 during the development of locular and placenta tissues of tomato fruits.


Assuntos
Frutas , Solanum lycopersicum , Gravidez , Feminino , Humanos , Solanum lycopersicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Retroalimentação , Placenta/metabolismo , Ácidos Indolacéticos/metabolismo , Homeostase , Regulação da Expressão Gênica de Plantas
5.
Opt Express ; 32(11): 20316-20325, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859145

RESUMO

Yellow lasers at 590 nm have many extensive applications in our daily life, but extremely difficult to attain by traditional solid-state laser technology, owing to the absence of highly-efficient transition channels at this spectral range. In this work, we proposed a cooperative lasing mechanism to obtain the yellow light emission, with multiphonon-assisted electronic transitions and phase-matched frequency-doubling. Based on the predictable configurational coordinate model, we can calculate the multiphonon-assisted emission step-by-step. Using Yb3+-doped La2CaB10O19 crystal as an example, it is capable of producing yellow laser at 581-590 nm, with a maximum output power of 4.83 W and a high slope efficiency of 31.6%. To the best of our knowledge, it represents the highest power of solid-state yellow laser realized in one single crystal pumped by a laser diode. This power scaling can be assigned to the amplified phonon-assisted emission beyond the fluorescence spectrum, and optimized crystal angle for phase-matching condition. Such a compact, low-cost, and high-power laser device, provides an alternative candidate for the spectral "yellow-gap" where no practical solid-state laser exists at present.

6.
Opt Express ; 32(8): 13965-13977, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38859354

RESUMO

Light polarization rotations, created by applied optical field, are examined experimentally and theoretically in a photosensitive chiral nematic fluid. The polarization rotation of the transmitted beam is initiated by illuminating the sample with uniform UV light. The operation is tunable and reversible, depending on the UV intensity. It was revealed that the rotations can be ascribed to the optical-field-induced chirality effect, where the helical structure in chiral nematics changes in accordance with the UV intensity. The evolution of the helical structure as well as its effect on the light polarization upon illumination by uniform UV light have been monitored experimentally and compared by calculations based on the continuum theory. Our results proved that a polarization field with specific characteristics can be achieved using the remote and precise optical control.

7.
Opt Lett ; 49(3): 578-581, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38300063

RESUMO

An approach to obtain a yellow laser is demonstrated for the first time to our knowledge by the employment of an Nd3+-doped YVO4 crystal and a LBO frequency-doubling crystal. Differing from the previous stimulated self-Raman radiation of Nd:YVO4, a direct 1176 nm lasing, without a high-intensity intracavity 1064 nm laser, was realized by utilizing an electron-phonon coupling effect and amplifying the thermally activated vibronic transitions. Combining with intracavity frequency-doubling, a yellow laser at 588 nm was obtained. At the pump power of 14.3 W, the output power of the yellow laser was 1.17 W, corresponding to a diode-to-visible efficiency of 8.2%. Moreover, for the first time, the yellow laser at 584 nm with output power of 164 mW was realized by tuning the filter, indicating the great potential of such an electron-phonon coupling laser for a wavelength extension in the yellow regime.

8.
J Environ Manage ; 351: 119745, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061094

RESUMO

Applying biochar to soil has been recognized as a promising practice of climate-smart agriculture, with considerable potential in enhancing soil organic carbon (SOC) sequestration. Previous studies showed that biochar-induced increases in SOC stock varied substantially among experiments, while the explanatory factors responsible for such variability are still not well assessed. Here, we conducted an integrative meta-analysis of the magnitude and efficiency of biochar-induced change in SOC stock, using a database including 476 field measurements at 101 sites across the globe. Biochar amendment increased SOC stock by 6.13 ± 1.62 (95% confidence interval, CI) and 7.01 ± 1.11 (95% CI) Mg C ha-1, respectively, compared to their unfertilized (R0) and mineral nitrogen (N) fertilized (Rn) references. Of which approx. 52% (R0) and 50% (Rn) were contributed directly by biochar-C input. Corresponding biochar carbon efficiencies in R0 and Rn datasets were estimated as 58.20 ± 10.37% and 65.58 ± 9.26% (95% CI), respectively. The change magnitude of SOC stock increased significantly (p < 0.01) with the increasing amount of biochar-C input, while carbon efficiency of biochar showed an opposite trend. Biochar amendment sequestered larger amounts of SOC with higher efficiency in acidic and loamy soils than in alkaline and sandy soils. Biochar amendments with higher C/N ratio caused higher SOC increase than those with lower C/N ratio. Random forest (RF) algorithm showed that accumulative biochar-C input, soil pH, and biochar C/N ratio were the three most-important factors regulating the SOC stock responses. Overall, these results suggest that applying high C/N ratio biochar in acidic soils is a recommendable agricultural practice from the perspective of enhancing organic carbon.


Assuntos
Carbono , Solo , Carvão Vegetal , Agricultura/métodos , Sequestro de Carbono
9.
J Proteome Res ; 22(6): 1649-1659, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37126732

RESUMO

Exercise plays a beneficial role in the management of Alzheimer's disease (AD), but its effects on brain metabolism are still far from being understood. Here, we examined behavioral changes of APP/PS1 mice after high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT) and analyzed metabolomics profiles in the hippocampus, cortex, and hypothalamus by using nuclear magnetic resonance spectroscopy to explore potential metabolic mechanisms. The results demonstrate that both HIIT and MICT alleviated anxiety/depressive-like behaviors as well as learning and memory impairments of AD mice. Metabolomics analysis reveals that energy metabolism, neurotransmitter metabolism, and membrane metabolism were significantly altered in all three brain regions after both types of exercises. Amino acid metabolism was detected to be affected in the cortex and hypothalamus after HIIT and in the hippocampus and hypothalamus after MICT. However, only HIIT significantly altered astrocyte-neuron metabolism in the hippocampus and hypothalamus of AD mice. Therefore, our study suggests that exercise can shape brain metabolism of AD mice in a region- and exercise-specific manner, indicating that the precise modification of brain metabolism by a specific type of exercise might be a novel perspective for the prevention and treatment of AD.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Camundongos Transgênicos , Doença de Alzheimer/patologia , Encéfalo/metabolismo , Hipocampo/metabolismo
10.
J Am Chem Soc ; 145(40): 21925-21936, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696655

RESUMO

Chalcogenides, which refer to chalcogen anions, have attracted considerable attention in multiple fields of applications, such as optoelectronics, thermoelectrics, transparent contacts, and thin-film transistors. In comparison to oxide counterparts, chalcogenides have demonstrated higher mobility and p-type dopability, owing to larger orbital overlaps between metal-X covalent chemical bondings and higher-energy valence bands derived by p-orbitals. Despite the potential of chalcogenides, the number of successfully synthesized compounds remains relatively low compared to that of oxides, suggesting the presence of numerous unexplored chalcogenides with fascinating physical characteristics. In this study, we implemented a systematic high-throughput screening process combined with first-principles calculations on ternary chalcogenides using 34 crystal structure prototypes. We generated a computational material database containing over 400,000 compounds by exploiting the ion-substitution approach at different atomic sites with elements in the periodic table. The thermodynamic stabilities of the candidates were validated using the chalcogenides included in the Open Quantum Materials Database. Moreover, we trained a model based on crystal graph convolutional neural networks to predict the thermodynamic stability of novel materials. Furthermore, we theoretically evaluated the electronic structures of the stable candidates using accurate hybrid functionals. A series of in-depth characteristics, including the carrier effective masses, electronic configuration, and photovoltaic conversion efficiency, was also investigated. Our work provides useful guidance for further experimental research in the synthesis and characterization of such chalcogenides as promising candidates, as well as charting the stability and optoelectronic performance of ternary chalcogenides.

11.
Cancer ; 129(13): 1969-1985, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36994945

RESUMO

BACKGROUND: Neoadjuvant immunotherapy (nIT) is a rapidly emerging paradigm for advanced resectable non-small cell lung cancer (NSCLC). The objectives of this PRISMA/MOOSE/PICOD-guided systematic review and meta-analysis were (1) to assess the safety and efficacy of nIT, (2) to compare the safety and efficacy of neoadjuvant chemoimmunotherapy (nCIT) versus chemotherapy alone (nCT), and (3) to explore predictors of pathologic response with nIT and their association with outcomes. METHODS: Eligibility was resectable stage I-III NSCLC and the receipt of programmed death-1/programmed cell death ligand-1 (PD-L1)/cytotoxic T-lymphocyte-associated antigen-4 inhibitors before resection; other forms and modalities of neoadjuvant and/or adjuvant therapies were allowed. For statistical analysis, the Mantel-Haenszel fixed-effect or random-effect model was used, depending on the heterogeneity (I2 ). RESULTS: Sixty-six articles met the criteria (eight randomized studies, 39 prospective nonrandomized studies, and 19 retrospective studies). The pooled pathologic complete response (pCR) rate was 28.1%. The estimated grade ≥3 toxicity rate was 18.0%. Compared with nCT, nCIT achieved higher rates of pCR (odds ratio [OR], 7.63; 95% confidence interval [CI], 4.49-12.97; p < .001), progression-free survival (PFS) (hazard ratio [HR] 0.51; 95% CI, 0.38-0.67; p < .001), and overall survival (OS) (HR, 0.51; 95% CI, 0.36-0.74; p = .0003) but yielded similar toxicity rates (OR, 1.01; 95% CI, 0.67-1.52; p = .97). The results remained robust on sensitivity analysis when all retrospective publications were removed. pCR was associated with improved PFS (HR, 0.25; 0.15-0.43; p < .001) and OS (HR, 0.26; 95% CI, 0.10-0.67; p = .005). PD-L1 expressors (≥1%) were more likely to achieve a pCR (OR, 2.93; 95% CI, 1.22-7.03; p = .02). CONCLUSIONS: In patients with advanced resectable NSCLC, neoadjuvant immunotherapy was safe and efficacious. nCIT improved pathologic response rates and PFS/OS over nCT, particularly in patients who had tumors that expressed PD-L1, without increasing toxicities. PLAIN LANGUAGE SUMMARY: This meta-analysis of 66 studies showed that neoadjuvant immunotherapy for advanced resectable non-small cell lung cancer is safe and efficacious. Compared with chemotherapy alone, chemoimmunotherapy improved pathologic response rates and survival, particularly for patients who had tumors that expressed programmed cell death ligand-1, without increasing toxicities.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Terapia Neoadjuvante , Antígeno B7-H1 , Ligantes , Estudos Prospectivos , Estudos Retrospectivos , Imunoterapia/efeitos adversos , Imunoterapia/métodos
12.
Mol Phylogenet Evol ; 179: 107676, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36535519

RESUMO

The superfamily Eriophyoidea includes >5000 named species of very small phytophagous mites. As for many groups of phytophagous invertebrates, factors responsible for diversification of eriophyoid mites are unclear. Here, we used an inferred phylogeny of 566 putative species of eriophyoid mites based on fragments of two mitochondrial genes and two nuclear genes to examine factors associated with their massive evolutionary diversification through time. Our dated phylogeny indicates a Carboniferous origin for gymnosperm-associated Eriophyoidea with subsequent diversification involving multiple host shifts to angiosperms-first to dicots, and then to monocots or shifts back to gymnosperms-beginning in the Cretaceous period when angiosperms diverged. Speciation rates increased more rapidly in the Eriophyidae + Diptilomiopidae (mostly infesting angiosperms) than in the Phytoptidae (mostly infesting gymnosperms). Phylogenetic signal, speciation rates, dispersal and vicariance results combined with inferred topologies show that hosts played a key role in the evolution of eriophyoid mites. Speciation constrained by hosts was probably the main driver behind eriophyoid mite diversification worldwide. We demonstrate monophyly of the Eriophyoidea, whereas all three families, most subfamilies, tribes, and most genera are not monophyletic. Our time-calibrated tree provides a framework for further evolutionary studies of eriophyoid mites and their interactions with host plants as well as taxonomic revisions above the species level.


Assuntos
Magnoliopsida , Ácaros , Humanos , Animais , Filogenia , Ácaros/genética , Magnoliopsida/genética , Genes Mitocondriais , Núcleo Celular/genética
13.
Opt Express ; 31(6): 9790-9799, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-37157542

RESUMO

Coupling between electronic motions and the lattice vibrations, phonons could broaden the spectral bandwidth of the fluorescence spectroscopy by the energy transferring, which was recognized from the beginning of last century and successfully applied in many vibronic lasers. However, the laser performances under electron-phonon coupling were mainly prejudged by the experimental spectroscopy. The multiphonon participated lasing mechanism is still elusive and should be in-depth investigated. Here, a direct quantitative relationship between the laser performance and phonon participating dynamic process was derived in theory. With a transition metal doped alexandrite (Cr3+:BeAl2O4) crystal, the multiphonon coupled laser performance was manifested in experiments. Associated with the Huang-Rhys factor calculations and hypothesis, the multiphonon participated lasing mechanism with phonon numbers from 2 to 5 was discovered and identified. This work provides not only a credible model for understanding the multiphonon participated lasing, but should also boost the study of laser physics in the electron-phonon-photon coupled systems.

14.
Opt Lett ; 48(18): 4913-4916, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37707935

RESUMO

Stable and miniaturized orange lasers at 591 nm are in urgent demand for ophthalmology and dermatological treatment. However, at present, traditional dye lasers and nonlinear sum-frequency lasers are limited by their complex setup and high cost, whereas semiconductor laser diodes (LDs) emitting in the yellow-orange range suffer from low output power. Here, we propose a new, to the best of our knowledge, route to create self-frequency-doubling (SFD) orange laser with a combination of multiphonon-assisted lasing and nonlinear frequency-doubling in one crystal. Using Yb3+-doped YCa4O(BO3)3 (Yb:YCOB) crystal, we first realize a widely tunable laser beyond the fluorescence spectrum in the wavelength range of 1175-1248 nm. Then, by selecting the laser polarization and crystal angle to satisfy phase-matching conditions, we obtained a directly diode-pumped orange laser at 591.8 nm with 3.07-W output power and an optical-to-optical conversion efficiency of 13%. This work represents a new step forward for portable high-power solid-state orange lasers and provides an intriguing platform for electron-phonon coupled lasing.

15.
Mol Reprod Dev ; 90(3): 129-140, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682071

RESUMO

Potassium channels play essential roles in the regulation of male fertility. However, potassium channels mediating K+ currents in human sperm (IKSper ) remain controversial. Besides SLO3, the SLO1 potassium channel is a potential candidate for human sperm KSper. This study intends to elucidate the function of SLO1 potassium channel during human sperm capacitation. Human sperm were treated with iberiotoxin (IbTX, a SLO1 specific inhibitor) and clofilium (SLO3 inhibitor) separately or simultaneously during in vitro capacitation. A computer-assisted sperm analyzer was used to assess sperm motility. The sperm acrosome reaction (AR) was analyzed using fluorescein isothiocyanate-conjugated Pisum sativum agglutinin staining. Sperm protein tyrosine phosphorylation was studied using western blotting. Intracellular Ca2+ , K+ , Cl- , and pH were analyzed using ion fluorescence probes. Independent inhibition with IbTX or clofilium decreased the sperm hyperactivation, AR, and protein tyrosine phosphorylation, and was accompanied by an increase in [K+ ]i , [Cl- ]i , and pHi , but a decrease in [Ca2+ ]i . Simultaneously inhibition with IbTX and clofilium lower sperm hyperactivation and AR more than independent inhibition. The increase in [K+ ]i , [Cl- ]i , and pHi , and the decrease in [Ca2+ ]i were more pronounced. This study suggested that the SLO1 potassium channel may have synergic roles with SLO3 during human sperm capacitation.


Assuntos
Reação Acrossômica , Capacitação Espermática , Humanos , Masculino , Capacitação Espermática/fisiologia , Reação Acrossômica/fisiologia , Sêmen/metabolismo , Motilidade dos Espermatozoides , Espermatozoides/metabolismo , Canais de Potássio/metabolismo , Homeostase
16.
Inorg Chem ; 62(36): 14518-14522, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37625248

RESUMO

Organic-inorganic hybrid materials have attracted increasing attention due to their unique superiority by combining the features of organic parts with inorganic parts. Herein, two organic-inorganic hybrid nonlinear-optical crystals, [C5H6O2N3]2[IO3]2 (I) and [C5H6O2N3][HSO4]·H2O (II), were successfully synthesized in aqueous solution by selecting 2-amino-3-nitropyridine as the cation and different anions of [IO3]- and [HSO4]-. The two compounds crystallized in the noncentrosymmetric space groups of P21 and P212121, respectively. I displays second-harmonic-generation (SHG) effects of 2.4 × KDP (KH2PO4) and a large birefringence (Δncal ∼ 0.22). Moreover, II exhibits a stronger SHG response of 5.2 × KDP, an enhanced band gap (2.81 eV), as well as a large birefringence (Δncal ∼ 0.25). This work points out a new feasible path for the rational design of high-performance organic-inorganic hybrid materials.

17.
Inorg Chem ; 62(36): 14739-14747, 2023 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-37648654

RESUMO

Thioarsenites(III) are an advanced functional material platform owing to the stereochemically active lone pair cations. In this paper, two novel quaternary thioarsenites(III), AgMAsS3 (M = Cd, Hg), are successfully obtained by introducing double d10 cations. In the compounds, d10 cations show a variety of different coordination modes ([AgS4] and [HgS4] in AgHgAsS3 vs [AgS5] and [CdS6] in AgCdAsS3). As a result, AgHgAsS3 and AgCdAsS3 crystallize in the noncentrosymmetric Cc space group and centrosymmetric C2/c space group, respectively. The band gaps of AgHgAsS3 and AgCdAsS3 are determined experimentally as 1.90 and 2.20 eV, respectively. Meanwhile, title compounds exhibit strong photocurrent responses. Specifically, AgHgAsS3 has a large birefringence of 0.18 at 2100 nm and a moderate second harmonic generation of (0.5 × AgGaS2). Moreover, the origin of linear and nonlinear optical responses is investigated based on first-principles calculations. This study enriches the family of MI-MII-As-Q (M = Ag, Cu; MII = Zn, Cd, Hg; Q = chalcogen) chalcogenides and helps to understand and design other multifunctional optical materials.

18.
Inorg Chem ; 62(42): 17522-17529, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37826858

RESUMO

Nonlinear optical (NLO) materials have aroused increasing interest owing to their promising applications in optoelectronic technologies. Herein, we present the synthesis of an acentric niobium tellurite crystal, Nb2Te3O11, extracted via a spontaneous crystallization approach. It adopts a unique three-dimensional (3D) structure constructed by the distorted [TeO3], [TeO4], and [NbO6] fundamental building units. The title compound undergoes incongruent melting at approximately 807 °C. Optical characterizations demonstrate that Nb2Te3O11 possesses an extended transparency window beyond 5 µm, along with a large band gap value of 3.1 eV. Moreover, the as-synthesized Nb2Te3O11 displays an appreciable second-harmonic generation (SHG) response of 2 × KDP and a notable birefringence of 0.11 under 1064 nm for achieving phase-matching. In addition, theoretical calculation investigations suggest that the intriguing optical properties are ascribed to the cooperative effect of three types of NLO-active motifs: [TeO3] pyramids, [TeO4] seesaws, and [NbO6] octahedra. These attributes provide new functional insights into Nb2Te3O11 and enrich the family of NLO crystals in the mid-infrared region.

19.
Neuroradiology ; 65(1): 185-194, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35922586

RESUMO

PURPOSE: Imaging features of cerebral arteriovenous malformations (AVMs) are mainly interpreted according to demographic and qualitative anatomical characteristics. This study aimed to use angiographic parametric imaging (API)-derived radiomics features to explore whether these features extracted from digital subtraction angiography (DSA) were associated with the hemorrhagic presentation of AVMs. METHODS: Patients with AVM were retrospectively evaluated. Among them, 80% were randomly assigned to a training dataset, and the remaining 20% were assigned to an independent test dataset. Radiomics features were extracted from DSA by API. Then, informative features were selected from radiomics features and clinical features using the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm. A model was constructed based on the selected features to classify the dichotomous hemorrhagic presentation in the training dataset. The model performance was evaluated in the test dataset with confusion matrix-related metrics. RESULTS: A total of 529 consecutive patients with AVMs between July 2011 and December 2020 were included in this study. After being selected by the LASSO algorithm and analyzed by multivariable logistic regression, three clinical features, namely, age (p = 0.01), nidus size (p < 0.001), and venous drainage patterns (p < 0.001), and four radiomics features were used to construct a model in the training dataset. On the independent test dataset, the model demonstrated a sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 0.852, 0.844, 0.881, 0.809, and 0.849, respectively. CONCLUSION: The radiomics features extracted from DSA by API could be potential indicators for the hemorrhagic presentation of AVMs.


Assuntos
Hemodinâmica , Malformações Arteriovenosas Intracranianas , Humanos , Estudos Retrospectivos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Angiografia Digital/métodos , Valor Preditivo dos Testes
20.
Bioorg Chem ; 136: 106543, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37119784

RESUMO

Curcumin is identified that it has the potential to treat Parkinson's disease (PD), but its instability limits its further application in clinic. The mono-carbonyl analogs of curcumin (MACs) with diketene structure can effectively improve its stability, but it is highly toxic. In the present study, a less cytotoxic and more stable monoketene MACs skeleton S2 was obtained, and a series of monoketene MACs were synthesized by combining 4-hydroxy-3­methoxy groups of curcumin. In the 6-OHDA-induced PD's model in-vitro, some compounds exhibited significant neurotherapeutic effect. The quantitative structure-activity relationship (QSAR) model established by the random forest algorithm (RF) for the cell viability rate of above compounds showed that the statistical results are good (R2 = 0.883507), with strong reliability. Among all compounds, the most active compound A4 played an important role in neuroprotection in the PD models both in vitro and in vivo by activating AKT pathway, and then inhibiting the apoptosis of cells caused by endoplasmic reticulum (ER) stress. In the PD model in-vivo, compound A4 significantly improved survival of dopaminergic neurons and the contents of neurotransmitters. It also enhanced the retention of nigrostriatal function which was better than the effect in the mice treated by Madopar, a classical clinical drug for PD. In summary, we screened out the compound A4 with high stability, less cytotoxic monoketene compounds. And these founding provide evidence that the compound A4 can protect dopaminergic neurons via activating AKT and subsequently suppressing ER stress in PD.


Assuntos
Curcumina , Fármacos Neuroprotetores , Doença de Parkinson , Animais , Camundongos , Apoptose , Curcumina/farmacologia , Curcumina/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reprodutibilidade dos Testes
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