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The peak photoluminescence (PL) of conventional fluorophores is independent of the excitation wavelength (called Kasha's rule), while the search of metal-organic framework materials with the so-called anti-Kasha's rule emission remains very limited. Herein, we report the observation of anti-Kasha's rule emission in a multicomponent PL three-dimensional nanotubular metal-organic framework (abbr. MOF-NT), [Zn(µ-L)(µ-bix)]n·0.33nH2O [H2L = biphenyl-3,5-dicarboxylic acid; bix = 1,4-bis(imidazole-1-ylmethyl)benzene]. The MOF-NT crystalline sample represents a notable example of strong excitation-dependent fluorescence from the ultraviolet to the visible spectral region. Moreover, by virtue of electronic flexibility and high PL efficiency, MOF-NT shows a discriminative PL response between isomeric nitroaromatic compounds. The work demonstrated the intrinsic anti-Kasha's rule emission in the crystalline-state MOF materials, providing new visions for the development of advanced solid-state emissive materials.
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Spin manipulation of transition-metal catalysts has great potential in mimicking enzyme electronic structures to improve activity and/or selectivity. However, it remains a great challenge to manipulate room-temperature spin state of catalytic centers. Herein, we report a mechanical exfoliation strategy to in situ induce partial spin crossover from high-spin (s=5/2) to low-spin (s=1/2) of the ferric center. Due to spin transition of catalytic center, mixed-spin catalyst exhibits a high CO yield of 19.7â mmol g-1 with selectivity of 91.6 %, much superior to that of high-spin bulk counterpart (50 % selectivity). Density functional theory calculations reveal that low-spin 3d-orbital electronic configuration performs a key function in promoting CO2 adsorption and reducing activation barrier. Hence, the spin manipulation highlights a new insight into designing highly efficient biomimetic catalysts via optimizing spin state.
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Phosphor-converted white light-emitting diodes (pc-wLEDs) are promising candidates for next-generation solid-state lighting and display technologies. However, most of the conventional phosphors in pc-wLED devices suffer from serious thermal quenching (TQ) at high temperatures. Herein, we investigate an unconventional high-efficiency metal-halide cluster-based phosphor with dynamic Cu-Cu interactions that can resist the TQ effect of photoluminescence. The temperature-dependent structure and solid-state and in situ NMR spectroscopy reveal that the weakening of the Cu-Cu interaction in such a phosphor system enables the electronic structural transition from a bonding to a nonbonding state and hence sustains the PL efficiency at high temperatures (up to 100 °C). The pc-wLEDs incorporating the zero-TQ phosphor show a rapid brightness rise even at a high bias current (1000 mA) with a color rendering index as high as 90, comparable to the commercial phosphor-based prototype LEDs (e.g., YAG:Ce3+). This work establishes a novel prototype of a cluster-based phosphor featuring dynamic intermetallic interactions, which paves the way for the exploration of pc-wLEDs against thermal quenching.
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Solid-state lighting technology, where light-emitting diodes (LEDs) are used for energy conversion from electricity to light, is considered a next-generation lighting technology. One of the significant challenges in the field is the synthesis of high-efficiency phosphors for designing phosphor-converted white LEDs under high flux operating currents. Here, we reported the synthesis, structure, and photophysical properties of a tetranuclear Cu(I)-halide cluster phosphor, [bppmCu2I2]2 (bppm = bisdiphenylphosphinemethane), for the fabrication of high-performance white LEDs. The PL investigations demonstrated that the red emission exhibits a near-unity photoluminescence quantum yield at room temperature and unusual spectral broadening with increasing temperature in the crystalline state. Considering the excellent photophysical properties, the crystalline sample of [bppmCu2I2]2 was successfully applied for the fabrication of phosphor-converted white LEDs. The prototype white LED device exhibited a continuous rise in brightness in the range of a high bias current (100-1000 mA) with CRI as high as 84 and CCT of 5828 K, implying great potential for high-quality white LEDs.
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The microstructure of the extracellular matrix (ECM) plays a key role in affecting cell migration, especially nonproteolytic migration. It is difficult, however, to measure some properties of the ECM, such as stiffness and the passability for cell migration. On the basis of a network model of collagen fiber in the ECM, which has been well applied to simulate mechanical behaviors such as the stress-strain relationship, damage, and failure, we proposed a series of methods to study the microstructural properties containing pore size and pore stiffness and to search for the possible migration paths for cells. Finally, with a given criterion, we quantitatively evaluated the passability of the ECM network for cell migration. The fiber network model with a microstructure and the analysis method presented in this study further our understanding of and ability to evaluate the properties of an ECM network.
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Matriz Extracelular , Movimiento CelularRESUMEN
Background: Anxiety disorders have emerged as one of the most prevalent mental health problems and health concerns. However, previous research has paid limited attention to measuring public anxiety from a broader perspective. Furthermore, while we know many factors that influence anxiety disorders, we still have an incomplete understanding of how these factors affect public anxiety. We aimed to quantify public anxiety from the perspective of Internet searches, and to analyze its spatiotemporal changing characteristics and influencing factors. Methods: This study collected Baidu Index from 2014 to 2022 in 31 provinces in mainland China to measure the degree of public anxiety based on the Baidu Index from 2014 to 2022. The spatial autocorrelation analysis method was used to study the changing trends and spatial distribution characteristics of public anxiety. The influencing factors of public anxiety were studied using spatial statistical modeling methods. Results: Empirical analysis shows that the level of public anxiety in my country has continued to rise in recent years, with significant spatial clustering characteristics, especially in the eastern and central-southern regions. In addition, we constructed ordinary least squares (OLS) and geographically weighted regression (GWR) spatial statistical models to examine the relationship between social, economic, and environmental factors and public anxiety levels. We found that the GWR model that considers spatial correlation and dependence is significantly better than the OLS model in terms of fitting accuracy. Factors such as the number of college graduates, Internet traffic, and urbanization rate are significantly positively correlated with the level of public anxiety. Conclusion: Our research results draw attention to public anxiety among policymakers, highlighting the necessity for a more extensive examination of anxiety issues, especially among university graduates, by the public and relevant authorities.
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Ansiedad , Humanos , China/epidemiología , Ansiedad/epidemiología , Femenino , Masculino , Trastornos de Ansiedad/epidemiología , Adulto , Internet/estadística & datos numéricosRESUMEN
PURPOSE: This study aimed to evaluate the impact of intravitreal triamcinolone acetonide (TA) administration after peeling of idiopathic epiretinal membranes (iERM) on both anatomical and visual outcomes, utilizing the ectopic inner foveal layer (EIFL) staging scheme. METHODS: In this retrospective case-control study, we analyzed 43 eyes from 43 patients diagnosed with iERM between June 2019 and December 2021. All participants were categorized into the TA or control groups based on administering intravitreal TA injection following ERM peeling. We thoroughly reviewed the clinical data, including the preoperative and postoperative best-corrected visual acuity (BCVA), central foveal thickness (CFT), and macular cube volume (VOL), with ERM stages classified according to the EIFL staging scheme. RESULTS: The study enrolled 22 eyes in the TA and 21 in the control groups. Following a mean follow-up period of 11.07 ± 2.02 months, noteworthy improvements in EIFL stages were observed in both cohorts (p < 0.01), but without significant distinctions between groups. In the TA group, 63.64% of eyes demonstrated improvements in EIFL stages, while the control group exhibited 76.19% (p = 0.37). At the final visit, both groups experienced a noteworthy reduction in the postoperative CFT and VOL (p < 0.05), coupled with significant improvement in BCVA (p < 0.01). No substantial differences appeared between the two groups concerning BCVA, CFT, and VOL (all p > 0.05). CONCLUSIONS: Our study suggested that concurrent intravitreal TA injection following ERM removal did not provide additional benefits regarding anatomical and visual improvement in iERM cases classified as Stages 2 and 3.
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Automatic and precise polyp segmentation in colonoscopy images is highly valuable for diagnosis at an early stage and surgery of colorectal cancer. Nevertheless, it still posed a major challenge due to variations in the size and intricate morphological characteristics of polyps coupled with the indistinct demarcation between polyps and mucosas. To alleviate these challenges, we proposed an improved dual-aggregation polyp segmentation network, dubbed Dua-PSNet, for automatic and accurate full-size polyp prediction by combining both the transformer branch and a fully convolutional network (FCN) branch in a parallel style. Concretely, in the transformer branch, we adopted the B3 variant of pyramid vision transformer v2 (PVTv2-B3) as an image encoder for capturing multi-scale global features and modeling long-distant interdependencies between them whilst designing an innovative multi-stage feature aggregation decoder (MFAD) to highlight critical local feature details and effectively integrate them into global features. In the decoder, the adaptive feature aggregation (AFA) block was constructed for fusing high-level feature representations of different scales generated by the PVTv2-B3 encoder in a stepwise adaptive manner for refining global semantic information, while the ResidualBlock module was devised to mine detailed boundary cues disguised in low-level features. With the assistance of the selective global-to-local fusion head (SGLFH) module, the resulting boundary details were aggregated selectively with these global semantic features, strengthening these hierarchical features to cope with scale variations of polyps. The FCN branch embedded in the designed ResidualBlock module was used to encourage extraction of highly merged fine features to match the outputs of the Transformer branch into full-size segmentation maps. In this way, both branches were reciprocally influenced and complemented to enhance the discrimination capability of polyp features and enable a more accurate prediction of a full-size segmentation map. Extensive experiments on five challenging polyp segmentation benchmarks demonstrated that the proposed Dua-PSNet owned powerful learning and generalization ability and advanced the state-of-the-art segmentation performance among existing cutting-edge methods. These excellent results showed our Dua-PSNet had great potential to be a promising solution for practical polyp segmentation tasks in which wide variations of data typically occurred.
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OBJECTIVES: This study aimed to assess weight changes following antipsychotic treatment in first-episode schizophrenia (FES) patients and make a comparison of aripiprazole, risperidone and olanzapine. Predictors for long-term clinically relevant weight gain (CRW, ≥7%) were examined. METHODS: We carried out a second analysis of data from the Chinese First-Episode Schizophrenia Trial. Repeated measures general linear model (GLM) statistics were used to compare body weight at each follow-up point (month of 1, 2, 3, 6, 9and 12). Logistic regression models were constructed to evaluate possible predictors for CRW. RESULTS: Body weight increased with an average rate of 0.93 % per month, with the fastest growth rate occurring in first 3 months. CRW was observed in 79 % of patients. Participants from olanzapine group showed significantly higher weight gain than risperidone group and aripiprozole group. Repeated measures GLM revealed a significant main effect of time (p < 0.001) and asignificant time*group interaction was revealed (p < 0.001), while the between-subject group effect was not statistically significant (p = 0.272). Multivariate logistic regressionmodel showed that with smaller baseline BMI (OR = 1.33, p < 0.001), with a family history of mental disorder (OR = 5.08, p = 0.004), receiving olanzapine (OR = 2.35, p = 0.001), and CRW at first-month (OR = 4.29, p = 0.032) were independent predictors for first-year CRW. CONCLUSION: Antipsychotics are associated with a clinically significant weight gain in FES patients, which occurs mostly in first 3 months. Aripiprazole might not be an ideal choice in terms of long-term metabolic side-effects. Early and close metabolic monitoring should accompany antipsychotic prescription.
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Antipsicóticos , Esquizofrenia , Humanos , Olanzapina/efectos adversos , Risperidona/efectos adversos , Aripiprazol/efectos adversos , Antipsicóticos/efectos adversos , Esquizofrenia/tratamiento farmacológico , Benzodiazepinas/efectos adversos , Peso Corporal , Aumento de PesoRESUMEN
High-temperature negative thermal quenching (NTQ) phosphors are crucial to high-performance light-emitting devices. Herein, we report the high-temperature NTQ effect in deep-red to near-infrared (NIR) emitting copper iodide cluster-based coordination polymers as unconventional phosphors, whose NTQ operating temperature can reach as high as 500 K, the highest temperature reached by NTQ molecular-based materials.
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Objective: Negative symptoms can seriously affect social functioning in patients with schizophrenia. However, the role of various components of negative symptoms in social functioning remains unclear. This study aimed to explore the associations among three different dimensions of negative symptoms (i.e., communication, emotion, and motivation) and social functioning to identify potential therapeutic targets. Methods: This cross-sectional study enrolled 202 Chinese participants with schizophrenia. Negative symptoms were evaluated using the Negative Symptom Assessment (NSA). Social functioning was represented by the Personal and Social Performance Scale (PSP) total score and employment status. Correlation analysis was conducted to clarify the relationship between negative symptoms and the PSP total score. Regression analysis was performed to explore the determinants of the PSP total score and employment status, considering negative symptoms and possible confounders, such as demographic features, positive symptoms, cognitive symptoms, depressive symptoms, and extrapyramidal side effects. Results: The PSP total score was correlated with all three dimensions of negative symptoms (i.e., emotion, motivation, and communication; rs = -0.509, -0.662, and -0.657, respectively). Motivation, instead of emotion or communication, predicted both low PSP total scores and unemployment. Conclusion: Social functioning in patients with schizophrenia was significantly related to motivation. Further studies should focus on motivation and consider it as a therapeutic target to improve patients' social functioning.
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Negative symptoms play an important role in development and treatment of schizophrenia. However, brain changes relevant to negative symptoms are still unclear. This study examined brain structural abnormalities and their asymmetry in schizophrenia patients and the association with negative symptoms. Fifty-nine schizophrenia patients and 66 healthy controls undertook structural brain scans. Schizophrenia patients were further divided into predominant negative symptoms (PNS, n = 18) and non-PNS (n = 34) subgroups. Negative symptoms were assessed by the Negative Symptom Assessment (NSA). T1-weighted images were preprocessed with FreeSurfer to estimate subcortical volumes, cortical thickness and surface areas, asymmetry Index (AI) was then calculated. MANOVA was performed for group differences while partial correlations in patients were analyzed between altered brain structures and negative symptoms. Compared to healthy controls, schizophrenia patients exhibited thinner cortices in frontal and temporal regions, and decreased leftward asymmetry of superior temporal gyrus (STG) in cortical thickness. Patients with PNS exhibited increased rightward asymmetry of amygdala volumes than non-PNS subgroup. In patients, AI of cortical thickness in the STG was negatively correlated with NSA-Emotion scores (r = -0.30, p = 0.035), while AI of amygdala volume was negatively correlated with NSA-Communication (r = -0.30, p = 0.039) and NSA-Total scores (r = -0.30, p = 0.038). Our findings suggested schizophrenia patients exhibited cortical thinning and altered lateralization of brain structures. Emotion and communication dimensions of negative symptoms also correlated with the structural asymmetry of amygdala and superior temporal regions in schizophrenia patients.
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The extracellular matrix (ECM) provides structural and biochemical support to cells and tissues, which is a critical factor for modulating cell dynamic behavior and intercellular communication. In order to further understand the mechanisms of the interactive relationship between cell and the ECM, we developed a three-dimensional (3D) collagen-fiber network model to simulate the micro structure and mechanical behaviors of the ECM and studied the stress-strain relationship as well as the deformation of the ECM under tension. In the model, the collagen-fiber network consists of abundant random distributed collagen fibers and some crosslinks, in which each fiber is modeled as an elastic beam and a crosslink is modeled as a linear spring with tensile limit, it means crosslinks will fail while the tensile forces exceed the limit of spring. With the given parameters of the beam and the spring, the simulated tensile stress-strain relation of the ECM highly matches the experimental results including damaged and failed behaviors. Moreover, by applying the maximal inscribed sphere method, we measured the size distribution of pores in the fiber network and learned the variation of the distribution with deformation. We also defined the alignment of the collagen-fibers to depict the orientation of fibers in the ECM quantitatively. By the study of changes of the alignment and the damaged crosslinks against the tensile strain, this paper reveals the comprehensive mechanisms of four stages of 'toe', 'linear', 'damage' and 'failure' in the tensile stress-strain relation of the ECM which can provide further insight in the study of cell-ECM interaction.