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1.
Hum Brain Mapp ; 45(1): e26561, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38096866

RESUMO

Non-negligible idiosyncrasy due to interindividual differences is an ongoing issue in resting-state functional MRI (rfMRI) analysis. We show that a deep neural network (DNN) can be employed for individual identification by learning important features from the time-varying functional connectivity (FC) of rfMRI in the Human Connectome Project. We employed the trained DNN to identify individuals from an independent dataset acquired at our institution. The results revealed that the DNN could successfully identify 300 individuals with an error rate of 2.9% using 15 s time-window and 870 individuals with an error rate of 6.7%. A trained DNN with nonlinear hidden layers led to the proposal of the "fingerprint of FC" (fpFC) as representative edges of individual FC. The fpFCs for individuals exhibited commonly important and individual-specific edges across time-window lengths (from 5 min to 15 s). Furthermore, the utility of our model for another group of subjects was validated, supporting the feasibility of our technique in the context of transfer learning. In conclusion, our study offers an insight into the discovery of the intrinsic mode of the human brain using whole-brain resting-state FC and DNNs.


Assuntos
Conectoma , Imageamento por Ressonância Magnética , Humanos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Encéfalo/diagnóstico por imagem , Conectoma/métodos
2.
Hum Brain Mapp ; 44(5): 2018-2038, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36637109

RESUMO

We investigated neural representations for visual perception of 10 handwritten digits and six visual objects from a convolutional neural network (CNN) and humans using functional magnetic resonance imaging (fMRI). Once our CNN model was fine-tuned using a pre-trained VGG16 model to recognize the visual stimuli from the digit and object categories, representational similarity analysis (RSA) was conducted using neural activations from fMRI and feature representations from the CNN model across all 16 classes. The encoded neural representation of the CNN model exhibited the hierarchical topography mapping of the human visual system. The feature representations in the lower convolutional (Conv) layers showed greater similarity with the neural representations in the early visual areas and parietal cortices, including the posterior cingulate cortex. The feature representations in the higher Conv layers were encoded in the higher-order visual areas, including the ventral/medial/dorsal stream and middle temporal complex. The neural representations in the classification layers were observed mainly in the ventral stream visual cortex (including the inferior temporal cortex), superior parietal cortex, and prefrontal cortex. There was a surprising similarity between the neural representations from the CNN model and the neural representations for human visual perception in the context of the perception of digits versus objects, particularly in the primary visual and associated areas. This study also illustrates the uniqueness of human visual perception. Unlike the CNN model, the neural representation of digits and objects for humans is more widely distributed across the whole brain, including the frontal and temporal areas.


Assuntos
Encéfalo , Percepção Visual , Humanos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação , Lobo Parietal/diagnóstico por imagem , Mapeamento Encefálico/métodos , Reconhecimento Visual de Modelos
3.
Brain Cogn ; 169: 106001, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37235929

RESUMO

We systematically investigated the link between trait mindfulness scores and functional connectivity (FC) features or behavioral data, to emphasize the importance of the reliability of self-report mindfulness scores. Sixty healthy young male participants underwent two functional MRI runs with three mindfulness or mind-wandering task blocks with an N-back task (NBT) block. The data from 49 participants (age: 23.3 ± 2.8) for whom two sets of the self-reported Mindfulness Attention Awareness Scale (MAAS) and NBT performance were available were analyzed. We divided participants into two groups based on the consistency level of their MAAS scores (i.e., a "consistent" and an "inconsistent" group). Then, the association between the MAAS scores and FC features or NBT performance was investigated using linear regression analysis with p-value correction and bootstrapping. Meaningful associations (a) between MAAS and NBT accuracy (slope = 0.41, CI = [0.10, 0.73], corrected p < 0.05), (b) between MAAS and the FC edges in the frontoparietal network, and (c) between the FC edges and NBT performance were only observed in the consistent group (n = 26). Our findings demonstrate the importance of appropriate screening mechanisms for self-report-based dispositional mindfulness scores when trait mindfulness scores are combined with neuronal features and behavioral data.


Assuntos
Memória de Curto Prazo , Atenção Plena , Humanos , Masculino , Adulto Jovem , Adulto , Autorrelato , Reprodutibilidade dos Testes , Atenção/fisiologia
4.
J Enzyme Inhib Med Chem ; 38(1): 2189097, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36927348

RESUMO

The design of kinase inhibitors targeting the oncogenic kinase BCR-ABL constitutes a promising paradigm for treating chronic myeloid leukaemia (CML). Nevertheless, the efficacy of imatinib, the first FDA-approved targeted therapy for CML, is curbed by the emergence of resistance. Herein, we report the identification of the 2-methoxyphenyl ureidobenzothiazole AK-HW-90 (2b) as a potent pan-BCR-ABL inhibitor against imatinib-resistant mutants, particularly T315I. A concise array of six compounds 2a-f was designed based on our previously reported benzothiazole lead AKE-5l to improve its BCR-ABLT315I inhibitory activity. Replacing the 6-oxypicolinamide moiety of AKE-5l with o-methoxyphenyl and changing the propyl spacer with phenyl afforded 2a and AK-HW-90 (2b) with IC50 values of 2.0 and 0.65 nM against BCR-ABLT315I, respectively. AK-HW-90 showed superior anticancer potency to imatinib against multiple cancer cells (NCI), including leukaemia K-562. The obtained outcomes offer AK-HW-90 as a promising candidate for the treatment of CML and other types of cancer.


Assuntos
Proteínas de Fusão bcr-abl , Pirimidinas , Mesilato de Imatinib/farmacologia , Proteínas de Fusão bcr-abl/genética , Pirimidinas/farmacologia , Piperazinas/farmacologia , Benzamidas/farmacologia , Apoptose
5.
J Am Chem Soc ; 144(35): 16131-16138, 2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36007154

RESUMO

Single-atom catalysts (SACs) of non-precious transition metals (TMs) often show unique electrochemical performance, including the electrochemical carbon dioxide reduction reaction (CO2RR). However, the inhomogeneity in their structures makes it difficult to directly compare SACs of different TM for their CO2RR activity, selectivity, and reaction mechanisms. In this study, the comparison of isolated TMs (Fe, Co, Ni, Cu, and Zn) is systematically investigated using a series of crystalline molecular catalysts, namely TM-coordinated phthalocyanines (TM-Pcs), to directly compare the intrinsic role of the TMs with identical local coordination environments on the CO2RR performance. The combined experimental measurements, in situ characterization, and density functional theory calculations of TM-Pc catalysts reveal a TM-dependent CO2RR activity and selectivity, with the free energy difference of ΔG(*HOCO) - ΔG(*CO) being identified as a descriptor for predicting the CO2RR performance.

6.
Phys Rev Lett ; 128(17): 173001, 2022 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-35570421

RESUMO

We here report on a quantitative study of enantiomer-specific state transfer, performed in a pulsed, supersonic molecular beam. The chiral molecule 1-indanol is cooled to low rotational temperatures (1-2 K) and a selected rotational level in the electronic and vibrational ground state of the most abundant conformer is depleted via optical pumping on the S_{1}←S_{0} transition. Further downstream, three consecutive microwave pulses with mutually perpendicular polarizations and with a well-defined duration and phase are applied. The population in the originally depleted rotational level is subsequently monitored via laser-induced fluorescence detection. This scheme enables a quantitative comparison of experiment and theory for the transfer efficiency in what is the simplest enantiomer-specific state transfer triangle for any chiral molecule, that is, the one involving the absolute ground state level, |J_{K_{a}K_{c}}⟩=|0_{00}⟩. Moreover, this scheme improves the enantiomer enrichment by over an order of magnitude compared to previous works. Starting with a racemic mixture, a straightforward extension of this scheme allows one to create a molecular beam with an enantiomer-pure rotational level, holding great prospects for future spectroscopic and scattering studies.


Assuntos
Vibração , Estereoisomerismo
7.
J Clin Immunol ; 40(4): 592-601, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32239366

RESUMO

PURPOSE: Although common variable immunodeficiency (CVID) is considered the most prevalent symptomatic primary antibody deficiency (PAD), there is a population with symptomatic PADs that do not meet criteria for CVID. We analyzed clinical and immunological profiles of patients with different PADs to better understand the differences and similarities between CVID and other PADs. METHODS: We extracted clinical and laboratory data of patients with PADs from electronic medical records. Patients were categorized into CVID, IgG subclass 2 deficiency (IgG2D), IgG deficiency (IgGD), and specific antibody deficiency (sAbD) based on basal immunoglobulin levels and pneumococcal vaccine responses. We compared clinical and immunological characteristics in these groups. RESULTS: All patients, regardless of PAD types, showed similar frequencies of infections, bronchiectasis, and interstitial lung disease (ILD). Hematopoietic malignancies were more frequently found in the CVID than in the IgG2D, IgGD, and sAbD groups, while the latter groups trended towards an increased frequency of connective tissue diseases (CTD). Low counts of natural killer (NK) cells were associated with malignancy, autoimmunity, and ILD in CVID but not in other PAD groups. CONCLUSIONS: Higher frequency of hematopoietic malignancy in CVID than in the other PADs and association of lower NK cell counts with non-infectious complications in CVID suggest a relationship between immune alterations and the development of non-infectious manifestations in PADs.


Assuntos
Imunodeficiência de Variável Comum/imunologia , Neoplasias Hematológicas/imunologia , Imunoglobulina G/genética , Infecções/imunologia , Células Matadoras Naturais/imunologia , Vacinas Pneumocócicas/imunologia , Doenças da Imunodeficiência Primária/imunologia , Adulto , Autoimunidade , Bronquiectasia , Imunodeficiência de Variável Comum/genética , Feminino , Neoplasias Hematológicas/genética , Humanos , Infecções/genética , Masculino , Pessoa de Meia-Idade , Doenças da Imunodeficiência Primária/genética , Adulto Jovem
8.
Neuroimage ; 195: 409-432, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-30953836

RESUMO

The triple networks, namely the default-mode network (DMN), the central executive network (CEN), and the salience network (SN), play crucial roles in disorders of the brain, as well as in basic neuroscientific processes such as mindfulness. However, currently, there is no consensus on the underlying functional features of the triple networks associated with mindfulness. In this study, we tested the hypothesis that (a) the partial regression coefficient (i.e., slope): from the SN to the DMN, mediated by the CEN, would be one of the potential mindfulness features in the real-time functional magnetic resonance imaging (rtfMRI) neurofeedback (NF) setting, and (b) this slope level may be enhanced by rtfMRI-NF training. Sixty healthy mindfulness-naïve males participated in an MRI session consisting of two non-rtfMRI-runs, followed by two rtfMRI-NF runs and one transfer run. Once the regions-of-interest of each of the triple networks were defined using the non-rtfMRI-runs, the slope level was calculated by mediation analysis and used as neurofeedback information, in the form of a thermometer bar, to assist with participant mindfulness during the rtfMRI-NF runs. The participants were asked to increase the level of the thermometer bar while deploying a mindfulness strategy, which consisted of focusing attention on the physical sensations of breathing. rtfMRI-NF training was conducted as part of a randomized controlled trial design, in which participants were randomly assigned to either an experimental group or a control group. The participants in the experimental group received contingent neurofeedback information, which was obtained from their own brain signals, whereas the participants in the control group received non-contingent neurofeedback information that originated from matched participants in the experimental group. Our results indicated that the slope level from the SN to the DMN, mediated by the CEN, was associated with mindfulness score (rtfMRI-NF runs: r = 0.53, p = 0.007; p-value was corrected from 10,000 random permutations) and with task-performance feedback score (rtfMRI-NF run: r = 0.61, p = 0.001) in the experimental group only. In addition, during the rtfMRI-NF runs the level of the partial regression coefficient feature was substantially increased in the experimental group compared to the control group (p < 0.05 from the paired t-test; the p-value was corrected from 10,000 random permutations). To the best of our knowledge, this is the first study to demonstrate a partial regression coefficient feature of mindfulness in the rtfMRI-NF setting obtained by triple network mediation analysis, as well as the possibility of enhancement of the partial regression coefficient feature by rtfMRI-NF training.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Atenção Plena , Neurorretroalimentação/métodos , Adulto , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino
9.
Bioorg Med Chem ; 26(21): 5596-5611, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30385226

RESUMO

Two new series of 5-subtituted and 5,6-disubstituted pyrrolo[2,3-d]pyrimidine octamides (4a-o and 6a-g) and their corresponding free amines 5a-m and 7a-g have been synthesized and biologically evaluated for their antiproliferative activity against three human cancer cell lines. The 5,6-disubstituted octamides 6d-g as well as the amine derivative 7b have shown the best anticancer activity with single digit micromolar GI50 values over the tested cancer cells, and low cytotoxic effects (GI50 > 10.0 µM) against HFF-1 normal cell. A structure activity relationship (SAR) study has been established and disclosed that terminal octamide moiety at C2 as well as disubstitution with fluorobenzyl piperazines at C5 and C6 of pyrrolo[2,3-d]pyrimidine are the key structural features prerequisite for best antiproliferative activity. Moreover, the most active member 6f was tested for its antiproliferative activity over a panel of 60 cancer cell lines at NCI, and exhibited distinct broad spectrum anticancer activity with submicromolar GI50 and TGI values over multiple cancer cells. Kinase profile of compound 6f over 53 oncogenic kinases at 10 µM concentration showed its highly selective inhibitory activity towards FGFR4, Tie2 and TrkA kinases. The observed activity of 6f against TrkA (IC50 = 2.25 µM), FGFR4 (IC50 = 6.71 µM) and Tie2 (IC50 = 6.84 µM) was explained by molecular docking study, which also proposed that 6f may be a type III kinase inhibitor, binding to an allosteric site rather than kinase hinge region. Overall, compound 6f may serve as a promising anticancer lead compound that could be further optimized for development of potent anticancer agents.


Assuntos
Antineoplásicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Humanos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/síntese química , Pirimidinas/química , Pirimidinas/farmacocinética , Pirróis/síntese química , Pirróis/química , Pirróis/farmacocinética , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/antagonistas & inibidores , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/química , Receptor TIE-2/antagonistas & inibidores , Receptor TIE-2/química , Receptor trkA/antagonistas & inibidores , Receptor trkA/química
10.
Bioorg Med Chem Lett ; 27(2): 237-241, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27914802

RESUMO

A novel series of heat shock protein 90 (Hsp90) inhibitors was identified by X-ray crystal analysis of complex structures at solvent-exposed exit pocket C. The 2-amino-pyrrolo[2,3-d]pyrimidine derivatives, 7-deazapurines substituted with a benzyl moiety at C5, showed potent Hsp90 inhibition and broad-spectrum antiproliferative activity against NCI-60 cancer cell lines. The most potent compound, 6a, inhibited Hsp90 with an IC50 of 36nM and showed a submicromolar mean GI50 value against NCI-60 cell lines. The interaction of 6a at the ATP-binding pocket of Hsp90 was confirmed by X-ray crystallography and Western blot analysis.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Pirimidinas/farmacologia , Pirróis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Modelos Moleculares , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
11.
Chem Pharm Bull (Tokyo) ; 62(12): 1214-24, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25297523

RESUMO

A novel series of oxazolidinone-class antimicrobial agents with 5-substituted octahydrocyclopenta[c]pyrrole moieties at the C-ring of linezolid and an acetamide or 1,2,3-triazole ring as the C-5 side chain of the oxazolidinone ring were prepared. The resulting series of compounds were evaluated for in vitro antimicrobial activity against Mycobacterium tuberculosis and a panel of clinically important resistant Gram-positive and -negative bacteria. Among them, endo-alcohol 2a and exo-alcohol 2b showed potent inhibitory activity against M. tuberculosis H37Rv, which was superior to that of linezolid. Several analogues in this series showed potent in vitro antibacterial activity against the clinically important vancomycin-resistant bacteria and showed similar or better potency against linezolid-resistant methicillin-resistant Staphylococcus aureus (MRSA) strains. The hydroxyl group in the azabicyclic C-ring interacted with the same hydrophobic pocket as linezolid based on a docking study. Selected compounds with high antimicrobial activity showed good human microsomal stability and low CYP isozyme and monoamine oxidase (MAO) inhibition.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Antituberculosos/síntese química , Antituberculosos/farmacologia , Compostos Azabicíclicos/síntese química , Compostos Azabicíclicos/farmacologia , Oxazóis/síntese química , Oxazóis/farmacologia , Pirrolidinas/síntese química , Pirrolidinas/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Inibidores Enzimáticos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Inibidores da Monoaminoxidase/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Resistência a Vancomicina
12.
Genome Biol Evol ; 16(4)2024 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-38526010

RESUMO

Human populations across a vast area in northern Eurasia, from Fennoscandia to Chukotka, share a distinct genetic component often referred to as the Siberian ancestry. Most enriched in present-day Samoyedic-speaking populations such as Nganasans, its origins and history still remain elusive despite the growing list of ancient and present-day genomes from Siberia. Here, we reanalyze published ancient and present-day Siberian genomes focusing on the Baikal and Yakutia, resolving key questions regarding their genetic history. First, we show a long-term presence of a unique genetic profile in southern Siberia, up to 6,000 yr ago, which distinctly shares a deep ancestral connection with Native Americans. Second, we provide plausible historical models tracing genetic changes in West Baikal and Yakutia in fine resolution. Third, the Middle Neolithic individual from Yakutia, belonging to the Belkachi culture, serves as the best source so far available for the spread of the Siberian ancestry into Fennoscandia and Greenland. These findings shed light on the genetic legacy of the Siberian ancestry and provide insights into the complex interplay between different populations in northern Eurasia throughout history.


Assuntos
Genética Populacional , Genoma Humano , População da Ásia Setentrional , Humanos , Sibéria
13.
Chem Commun (Camb) ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012327

RESUMO

This study comprehensively investigates the phase evolution of silver-carbon composite (Ag/C) layers in anode-less batteries with both liquid and solid electrolytes. The results of in situ X-ray diffraction and cross-sectional electron microscopy analyses reveal that the alloying reaction of Ag and Li is more homogeneous in solid-electrolyte-based cells compared to liquid-electrolyte-based cells. This homogeneity is attributed to diffusional Coble creep across the heterogeneous interfaces of Ag/C layers and solid electrolytes.

14.
ACS Nano ; 18(3): 1995-2005, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38214304

RESUMO

Transition metal (TM) based Prussian whites, comprising a cyanide anion ((C≡N)-) and TM cations in an alternative manner, have been widely adopted as cathode materials for rechargeable batteries. Prussian whites are characterized by the TM electronic states that exclusively adopt low spin (LS) toward the C atom and high spin (HS) toward the N atom through the hybridized covalent bonding in the TM─C≡N─TM unit with the average oxidation states of the TM ions being 2+, considerably affecting the phase transition behavior upon the release and storage of carrier ions; however, there have been only a few studies on their associated features. Herein, Prussian whites with different HS TM ions were synthesized via coprecipitation and the phase transition behavior controlled by the π electron interaction between the cyanide anions and TM ions during battery operations was investigated. In situ X-ray characterizations reveal that the combined effect of π backdonation in the LS Fe-C unit and π donation in the HS TM-N unit effectively controls the bond length of the TM─C≡N─TM building unit, thus markedly influencing the lattice volume of a series of Prussian white cathodes during the charge/discharge process. This study presents a comprehensive understanding of the structure-property relationship of the Prussian white cathodes involving π electron interactions during battery operations.

15.
Sci Total Environ ; 868: 161618, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-36649776

RESUMO

Microplastics (MPs) are a type of contaminants produced during the use and disposal of plastic products, which are ubiquitous in our lives. With the high specific surface area and strong hydrophobicity, MPs can adsorb various hazardous microorganisms and chemical contaminants from the environment, causing irreversible damage to our humans. It is reported that the MPs have been detected in infant feces and human blood. Therefore, the presence of MPs has posed a significant threat to human health. It is critically essential to develop efficient, scalable and environmentally-friendly methods to remove MPs. Herein, recent advances in the MPs remediation technologies in water and wastewater treatment processes are overviewed. Several approaches, including membrane filtration, adsorption, chemically induced coagulation-flocculation-sedimentation, bioremediation, and advanced oxidation processes are systematically documented. The characteristics, mechanisms, advantages, and disadvantages of these methods are well discussed and highlighted. Finally, the current challenges and future trends of these methods are proposed, with the aim of facilitating the remediation of MPs in water and wastewater treatment processes in a more efficient, scalable, and environmentally-friendly way.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Humanos , Microplásticos , Plásticos , Água , Águas Residuárias , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Purificação da Água/métodos
16.
ACS Appl Mater Interfaces ; 15(29): 35149-35160, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37439627

RESUMO

In this study, we incorporated TiN as a carrier suppressor into an amorphous InZnO channel to achieve stable channels for thin-film transistors (TFTs) and light-emitting transistors (LETs). The low electronegativity and standard electrode potential of the Ti dopant led to a reduction in the number of oxygen vacancies in the InZnO channel. Moreover, the substitution of nitrogen into the oxygen sites of InZnO effectively decreased the excess electrons. As a result, the cosputtering of the TiN dopant resulted in a decrease in the carrier concentration of the InZnO channel, serving as an effective carrier suppressor. Due to the distinct structures of TiN and InZnO, the TiN-doped InZnO channel exhibited a completely amorphous structure and a featureless surface morphology. The presence of oxygen vacancies in the InZnO channel creates trap states for electrons and holes. Consequently, the TFT with the InZnTiON channel demonstrated an improved subthreshold swing and enhanced stability during the gate bias stress test. Furthermore, the threshold voltage shift (ΔVth) changed from 3.29 to 0.86 V in the positive bias stress test and from -0.92 to -0.09 V in the negative bias stress test. Additionally, we employed an InZnTiON channel in LETs as a substitute for organic semiconductors. The reduction in the number of oxygen vacancies effectively prevented exciton quenching caused by hole traps within the vacancies. Consequently, appropriate TiN doping in the InZnO channel enhanced the intensity of the LET devices.

17.
Sci Adv ; 9(15): eadf3904, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37058560

RESUMO

The Xiongnu established the first nomadic imperial power, controlling the Eastern Eurasian steppe from ca. 200 BCE to 100 CE. Recent archaeogenetic studies identified extreme levels of genetic diversity across the empire, corroborating historical records of the Xiongnu Empire being multiethnic. However, it has remained unknown how this diversity was structured at the local community level or by sociopolitical status. To address this, we investigated aristocratic and local elite cemeteries at the western frontier of the empire. Analyzing genome-wide data from 18 individuals, we show that genetic diversity within these communities was comparable to the empire as a whole, and that high diversity was also observed within extended families. Genetic heterogeneity was highest among the lowest-status individuals, implying diverse origins, while higher-status individuals harbored less genetic diversity, suggesting that elite status and power was concentrated within specific subsets of the broader Xiongnu population.


Assuntos
Cemitérios , Genética Populacional , Humanos , Heterogeneidade Genética , Haplótipos , Filogenia
18.
ACS Appl Mater Interfaces ; 15(6): 7939-7948, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36625754

RESUMO

Layered lithium cobalt oxide (LiCoO2, LCO), which serves as a structural motif for the widely adopted layered cathodes in lithium-ion batteries, has a long history, and its unstable phase transition during high-voltage operation (∼4.5 V) remains an intractable problem. Many research strategies, such as surface coating and immobile ion doping, have been proposed to address this issue, but a clear understanding of the effects has not been demonstrated because of various potential parameters (e.g., particle size, shape, and dopant content). Herein, we report a molten salt synthesis method that produces sphere-like single-crystal magnesium (Mg)-doped LCO. In situ X-ray diffraction and X-ray absorption fine structure analyses confirmed that the lattice strain was effectively alleviated by the effects of both the particle shape and Mg doping compared to the plate-like and sphere-like single-crystal LCO samples. Furthermore, the preference for Mg doping in the Co site (3b) rather than in the Li site (3a) in the LCO framework is systematically revealed, and a clear understanding of Mg doping that suppresses the monoclinic phase transition is discussed in detail.

19.
Ann Surg Treat Res ; 105(1): 31-36, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37441320

RESUMO

Purpose: Whether administering chemotherapy followed by tamoxifen plus a gonadotropin-releasing hormone (GnRH) agonist to treat patients with lower-risk hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer provides a greater benefit than administering tamoxifen plus GnRH agonist alone remains unclear. This study aimed to compare the outcomes of propensity score-matched (PSM) patients who underwent these 2 types of treatment plans. Methods: This retrospective study included patients treated at our institution between 2009 and 2019. Eligible patients had HR-positive, HER2-negative, invasive breast cancer who had undergone surgery. There were 579 patients with HR-positive, HER2-negative breast cancer who were treated with a GnRH agonist and tamoxifen; patients with pathologic N2 and those who received neoadjuvant chemotherapy were excluded. After 1:1 PSM of patients who underwent GnRH agonist treatment and tamoxifen with versus without chemotherapy, 122 patients from these 2 groups were analyzed. Survival rates were calculated using the Kaplan-Meier method and compared via the log-rank test. Results: After PSM, there were no significant differences in several baseline characteristics between the 2 groups. After a median follow-up of 62.8 months, the patients in both groups demonstrated similar outcomes with no significant difference in disease-free survival (P = 0.596). Conclusion: Patients derived no significant survival benefit from undergoing a chemotherapy regimen before receiving tamoxifen and GnRH agonist therapy compared to forgoing such chemotherapy.

20.
Ann Surg Treat Res ; 105(1): 1-9, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37441319

RESUMO

Purpose: Although the overall survival (OS) of breast cancer patients is increasing with improved detection and therapies, so is the risk of breast cancer patients developing subsequent malignancies. We investigated the OS of breast cancer survivors according to sites of second primary malignancies (SPM). The OS of the second primary hematologic malignancy (SPHM) was then compared with that of metastatic breast cancer (MBC). Methods: We retrospectively analyzed patients diagnosed with primary breast cancer between 1998 and 2019. Only those with SPM were eligible for analysis. First, the OS of patients with SPM diagnosed as the first event after the diagnosis of breast cancer was analyzed. Next, the OS of patients with SPHM, with or without breast cancer relapse, was compared with that of patients with MBC, matched using the propensity score. Results: Patients diagnosed with SPM without breast cancer relapse as the first event had a significantly better OS than did patients with MBC, but the OS of those with SPHM as the first event did not differ significantly from that of patients with MBC (hazard ratio [HR], 1.558; 95% confidence interval [CI], 0.856-2.839; P = 0.147). The OS of patients with SPHM with or without breast cancer relapse was worse than that of the MBC group after propensity score matching (HR, 1.954; 95% CI, 1.045-3.654; P = 0.036). Conclusion: Prognosis of SPM diagnosed as the first event was statistically better than that of MBC, except in case of SPHM. Patients with SPHM, with or without MBC, showed poor OS before and after propensity score matching.

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