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The manipulation of excitation modes and resultant emission colors in luminescent materials holds pivotal importance for encrypting information in anti-counterfeiting applications. Despite considerable achievements in multimodal and multicolor luminescent materials, existing options generally suffer from static monocolor emission under fixed external stimulation, rendering them vulnerability to replication. Achieving dynamic multimodal luminescence within a single material presents a promising yet challenging solution. Here, we report the development of a phosphor exhibiting dynamic multicolor photoluminescence (PL) and photo-thermo-mechanically responsive multimodal emissions through the incorporation of trace Mn2+ ions into a self-activated CaGa4O7 host. The resulting phosphor offers adjustable emission-color changing rates, controllable via re-excitation intervals and photoexcitation powers. Additionally, it demonstrates temperature-induced color reversal and anti-thermal-quenched emission, alongside reproducible elastic mechanoluminescence (ML) characterized by high mechanical durability. Theoretical calculations elucidate electron transfer pathways dominated by intrinsic interstitial defects and vacancies for dynamic multicolor emission. Mn2+ dopants serve a dual role in stabilizing nearby defects and introducing additional defect levels, enabling flexible multi-responsive luminescence. This developed phosphor facilitates evolutionary color/pattern displays in both temporal and spatial dimensions using readily available tools, offering significant promise for dynamic anticounterfeiting displays and multimode sensing applications.
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Objectives: To examine the influence of adjuvant chemotherapy after radical resection on the survival of patients with intrahepatic cholangiocarcinoma(ICC) and to identify patients who may benefit from it. Methods: The clinical and pathological data of 654 patients with ICC diagnosed by postoperative pathology from December 2011 to December 2017 at 13 hospitals in China were collected retrospectively. According to the inclusion and exclusion criteria,455 patients were included in this study,including 69 patients (15.2%) who received adjuvant chemotherapy and 386 patients (84.8%) who did not receive adjuvant chemotherapy. There were 278 males and 177 females,with age of 59 (16) years (M(IQR))(range:23 to 88 years). Propensity score matching (PSM) method was used to balance the difference between adjuvant chemotherapy group and non-adjuvant chemotherapy group. Kaplan-Meier method was used to plot the survival curve,the Log-rank test was used to compare the difference of overall survival(OS) and recurrence free survival(RFS)between the two groups. Univariate analysis was used to determine prognostic factors for OS. Multivariate Cox proportional hazards models were then performed for prognostic factors with P<0.10 to identify potential independent risk factors. The study population were stratified by included study variables and the AJCC staging system,and a subgroup analysis was performed using the Kaplan-Meier method to explore the potential benefit subgroup population of adjuvant chemotherapy. Results: After 1∶1 PSM matching,69 patients were obtained in each group. There was no significant difference in baseline data between the two groups (all P>0.05). After PSM,Cox multivariate analysis showed that lymph node metastasis (HR=3.06,95%CI:1.52 to 6.16,P=0.039),width of resection margin (HR=0.56,95%CI:0.32 to 0.99,P=0.044) and adjuvant chemotherapy (HR=0.51,95%CI:0.29 to 0.91,P=0.022) were independent prognostic factors for OS. Kaplan-Meier analysis showed that the median OS time of adjuvant chemotherapy group was significantly longer than that of non-adjuvant chemotherapy group (P<0.05). There was no significant difference in RFS time between the adjuvant chemotherapy group and the non-adjuvant chemotherapy group (P>0.05). Subgroup analysis showed that,the OS of female patients,without HBV infection,carcinoembryonic antigen<9.6 μg/L,CA19-9≥200 U/ml,intraoperative bleeding<400 ml,tumor diameter>5 cm,microvascular invasion negative,without lymph node metastasis,and AJCC stage Ⅲ patients could benefit from adjuvant chemotherapy (all P<0.05). Conclusion: Adjuvant chemotherapy can prolong the OS of patients with ICC after radical resection,and patients with tumor diameter>5 cm,without lymph node metastasis,AJCC stage Ⅲ,and microvascular invasion negative are more likely to benefit from adjuvant chemotherapy.
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Objective: To establish a predictive model for survival benefit of patients with intrahepatic cholangiocarcinoma (ICC) who received adjuvant chemotherapy after radical resection. Methods: The clinical and pathological data of 249 patients with ICC who underwent radical resection and adjuvant chemotherapy at 8 hospitals in China from January 2010 to December 2018 were retrospectively collected. There were 121 males and 128 females,with 88 cases>60 years old and 161 cases≤60 years old. Feature selection was performed by univariate and multivariate Cox regression analysis. Overall survival time and survival status were used as outcome indicators,then target clinical features were selected. Patients were stratified into high-risk group and low-risk group,survival differences between the two groups were analyzed. Using the selected clinical features, the traditional CoxPH model and deep learning DeepSurv survival prediction model were constructed, and the performance of the models were evaluated according to concordance index(C-index). Results: Portal vein invasion, carcinoembryonic antigen>5 μg/L,abnormal lymphocyte count, low grade tumor pathological differentiation and positive lymph nodes>0 were independent adverse prognostic factors for overall survival in 249 patients with adjuvant chemotherapy after radical resection (all P<0.05). The survival benefit of adjuvant chemotherapy in the high-risk group was significantly lower than that in the low-risk group (P<0.05). Using the above five features, the traditional CoxPH model and the deep learning DeepSurv survival prediction model were constructed. The C-index values of the training set were 0.687 and 0.770, and the C-index values of the test set were 0.606 and 0.763,respectively. Conclusion: Compared with the traditional Cox model, the DeepSurv model can more accurately predict the survival probability of patients with ICC undergoing adjuvant chemotherapy at a certain time point, and more accurately judge the survival benefit of adjuvant chemotherapy.
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Objectives: To construct a nomogram for prediction of intrahepatic cholangiocarcinoma (ICC) lymph node metastasis based on inflammation-related markers,and to conduct its clinical verification. Methods: Clinical and pathological data of 858 ICC patients who underwent radical resection were retrospectively collected at 10 domestic tertiary hospitals in China from January 2010 to December 2018. Among the 508 patients who underwent lymph node dissection,207 cases had complete variable clinical data for constructing the nomogram,including 84 males,123 females,109 patients≥60 years old,98 patients<60 years old and 69 patients were pathologically diagnosed with positive lymph nodes after surgery. Receiver operating characteristic curve was drawn to calculate the accuracy of preoperative imaging examinations to determine lymph node status,and the difference in overall survival time was compared by Log-rank test. Partial regression squares and statistically significant preoperative variables were screened by backward stepwise regression analysis. R software was applied to construct a nomogram,clinical decision curve and clinical influence curve,and Bootstrap method was used for internal verification. Moreover,retrospectively collecting clinical information of 107 ICC patients with intraoperative lymph node dissection admitted to 9 tertiary hospitals in China from January 2019 to June 2021 was for external verification to verify the accuracy of the nomogram. 80 patients with complete clinical data but without lymph node dissection were divided into lymph node metastasis high-risk group and low-risk group according to the score of the nomogram among the 858 patients. Log-rank test was used to compare the overall survival of patients with or without lymph node metastasis diagnosed by pathology. Results: The area under the curve of preoperative imaging examinations for lymph node status assessment of 440 patients was 0.615,with a false negative rate of 62.8% (113/180) and a false positive rate of 14.2% (37/260). The median survival time of 207 patients used to construct a nomogram with positive or negative postoperative pathological lymph node metastases was 18.5 months and 27.1 months,respectively (P<0.05). Five variables related to lymph node metastasis were screened out by backward stepwise regression analysis,which were combined calculi,neutrophil/lymphocyte ratio,albumin,liver capsule invasion and systemic immune inflammation index,according to which a nomogram was constructed with concordance index(C-index) of 0.737 (95%CI: 0.667 to 0.806). The C-index of external verification was 0.674 (95%CI:0.569 to 0.779). The calibration prediction curve was in good agreement with the reference curve. The results of the clinical decision curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set to about 0.32,the maximum net benefit could be obtained by 0.11,and the cost/benefit ratio was 1∶2. The results of clinical influence curve showed that when the risk threshold of high lymph node metastasis in the nomogram was set to about 0.6,the probability of correctly predicting lymph node metastasis could reach more than 90%. There was no significant difference in overall survival time between patients with high/low risk of lymph node metastasis assessed by the nomogram and those with pathologically confirmed lymph node metastasis or without lymph node metastasis (Log-rank test:P=0.082 and 0.510,respectively). Conclusion: The prediction accuracy of preoperative nomogram for ICC lymph node metastasis based on inflammation-related markers is satisfactory,which can be used as a supplementary method for preoperative diagnosis of lymph node metastasis and is helpful for clinicians to make personalized decision of lymph node dissection for patients with ICC.
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Osteoarthritis (OA) has been recognized as an age-related degenerative disease commonly seen in the elderly that affects the whole "organ" including cartilage, subchondral bone, synovium, and muscles. An increasing number of studies have suggested that the accumulation of senescent cells triggering by various stresses in the local joint contributes to the pathogenesis of age-related diseases including OA. In this review, we mainly focus on the role of the senescent skeletal cells (chondrocytes, osteoblasts, osteoclasts, osteocyte, and muscle cells) in initiating the development and progression of OA alone or through cross-talk with the macrophages/synovial cells. Accordingly, we summarize the current OA-targeted therapies based on the abovementioned theory, e.g., by eliminating senescent skeletal cells and/or inhibiting the senescence-associated secretory phenotype (SASP) that drives senescence. Furthermore, the existing animal models for the study of OA from the perspective of senescence are highlighted to fill the gap between basic research and clinical applications. Overall, in this review, we systematically assess the current understanding of cellular senescence in OA, which in turn might shed light on the stratified OA treatments.
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Cartílago Articular , Osteoartritis , Sinoviocitos , Animales , Cartílago/patología , Cartílago Articular/patología , Senescencia Celular , Condrocitos/patología , Osteoartritis/patología , Sinoviocitos/patologíaRESUMEN
Objectives: To investigate the clinical value of adjuvant chemotherapy(ACT) in patients with intrahepatic cholangiocarcinoma(ICC) who underwent radical resection and to explore the optimal population that can benefit from ACT. Methods: A retrospective cohort study method was adopted. The clinical and pathological data of 685 patients with ICC who underwent curative intent resection in 10 Chinese hepatobiliary surgery centers from January 2010 to December 2018 were collected;There were 355 males and 330 females. The age(M(IQR)) was 58(14) years (range: 22 to 83 years). Propensity score matching(PSM) was applied to balance the differences between the adjuvant and non-adjuvant chemotherapy groups. Log-rank test was used to compare the prognosis of the two groups of patients. A Bayesian network recurrence-free survival(RFS) prediction model was constructed using the median RFS time (14 months) as the target variable, and the importance of the relevant prognostic factors was ranked according to the multistate Birnbaum importance calculation. A survival prognostic prediction table was established to analyze the population benefiting from adjuvant chemotherapy. Results: Among 685 patients,214 received ACT and 471 did not receive ACT. A total of 124 pairs of patients were included after PSM, and patients in the ACT group had better overall survival (OS) and RFS than those in the non-ACT group(OS: 32.2 months vs. 18.0 months,P=0.003;RFS:18.0 months vs. 10.0 months,P=0.001). The area under the curve of the Bayesian network RFS prediction model was 0.7124. The results of the prognostic factors in order of importance were microvascular invasion (0.158 2),perineural invasion (0.158 2),N stage (0.155 8),T stage (0.120 9), hepatic envelope invasion (0.090 3),adjuvant chemotherapy (0.072 1), tumor location (0.057 5), age (0.042 3), pathological differentiation (0.034 0), sex (0.029 3), alpha-fetoprotein (0.028 9) and preoperative jaundice (0.008 5). A survival prediction table based on the variables with importance greater than 0.1 (microvascular invasion,perineural invasion,N stage,T staging) and ACT showed that all patients benefited from ACT (increase in the probability of RFS≥14 months from 2.21% to 7.68%), with a more significant increase in the probability of RFS≥14 months after ACT in early-stage patients. Conclusion: ACT after radical resection in patients with ICC significantly prolongs the OS and RFS of patients, and the benefit of ACT is greater in early patients.
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Femenino , Humanos , Masculino , Teorema de Bayes , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/patología , Quimioterapia Adyuvante , Colangiocarcinoma/cirugía , Pronóstico , Estudios RetrospectivosRESUMEN
Objective: Constructing and validating a nomogram model for preoperative prediction of intrahepatic cholangiocarcinoma (ICC) lymph node metastasis to assist decision making during surgery. Methods: Retrospectively collecting the clinical and pathological data of 1 031 ICC patients who underwent partial hepatectomy at Eastern Hepatobiliary Surgery Hospital of Naval Military Medical University,General Hospital of Eastern Theater Command,or Zhongda Hospital Southeast University from January 2003 to January 2014. There were 682 males and 349 females; mean age was 54.7 years(range:18 to 82 years). There were 562 patients who underwent lymph node dissection and 469 patients who did not. Among the patients in the dissection group,Lasso regression method was used to filtrate preoperative variables related to lymph node metastasis and establish a nomogram. Bootstrap method was used to internally validate the discrimination of the nomogram,and the accuracy of the nomogram was assessed by using calibration curves. Patients were divided into low-moderate and high-risk groups based on model prediction probability. Propensity score matching(PSM) was used to analyze the overall survival (OS) and recurrence-free survival (RFS) of patients with and without lymph node dissection in the two groups,and to judge the importance of lymph node dissection in the two groups. Results: Six factors related to ICC lymph node metastasis were determined by Lasso regression,including hepatitis B surface antigen,CA19-9,age,lymphadenopathy,carcinoembryo antigen and maximum tumor diameter. These factors were integrated into a nomogram to predict ICC lymph node metastasis. The aera under curve value was 0.764,and the C-index was 0.754. Stratified analysis showed that OS and RFS in the high-risk group of lymph node metastasis were significantly lower than those in the low-medium risk group(median OS:14.6 months vs. 27.0 months,P<0.01; median RFS:9.1 months vs. 15.5 months,P<0.01). In the high-risk group,the median OS was 16.7 months and 6.3 months(Log-rank test: P=0.187;Wilcoxon test:P=0.046),and the median RFS was 11.0 months and 4.8 months(P=0.403),respectively in the lymph node dissection group and undissected group after PSM. In the low-medium-risk group,the median OS was 22.7 months and 26.7 months(P=0.288),and the median RFS was 13.0 months and 14.5 months(P=0.306),respectively in the lymph node dissection group and undissected group after PSM. Conclusions: The nomogram could be used for preoperative prediction of lymph node metastasis and prognostic stratification in patients with ICC. For patients with high risk of lymph node metastasis predicted by the model,active dissection should be performed. For patients predicted to be at low-moderate risk,lymph node dissection might be optional in some specific cases.
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Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/patología , Colangiocarcinoma/cirugía , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Metástasis Linfática , Nomogramas , Pronóstico , Estudios RetrospectivosRESUMEN
BACKGROUND: Circulating genetically abnormal cells (CACs) with specific chromosome variations have been confirmed to be present in non-small cell lung cancer (NSCLC). However, the diagnostic performance of CAC detection remains unclear. This study aimed to evaluate the potential clinical application of the CAC test for the early diagnosis of NSCLC. METHODS: In this prospective study, a total of 339 participants (261 lung cancer patients and 78 healthy volunteers) were enrolled. An antigen-independent fluorescence in situ hybridization was used to enumerate the number of CACs in peripheral blood. RESULTS: Patients with early-stage NSCLC were found to have a significantly higher number of CACs than those of healthy participants (1.34 vs. 0.19; P < 0.001). The CAC test displayed an area under the receiver operating characteristic (ROC) curve of 0.76139 for discriminating stage I NSCLC from healthy participants with 67.2% sensitivity and 80.8% specificity, respectively. Compared with serum tumor markers, the sensitivity of CAC assays for distinguishing early-stage NSCLC was higher (67.2% vs. 48.7%, P < 0.001), especially in NSCLC patients with small nodules (65.4% vs. 36.5%, P = 0.003) and ground-glass nodules (pure GGNs: 66.7% vs. 40.9%, P = 0.003; mixed GGNs: 73.0% vs. 43.2%, P < 0.001). CONCLUSIONS: CAC detection in early stage NSCLC was feasible. Our study showed that CACs could be used as a promising noninvasive biomarker for the early diagnosis of NSCLC. KEY POINTS: What this study adds: This study aimed to evaluate the potential clinical application of the CAC test for the early diagnosis of NSCLC. Significant findings of the study: CAC detection in early stage NSCLC was feasible. Our study showed that CACs could be used as a promising noninvasive biomarker for the early diagnosis of NSCLC.
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Biomarcadores de Tumor/sangre , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico , Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
Trap-controlled mechanoluminescent (ML) materials characterized by reproducible mechanoluminescence (ML) after irradiation recharging have shown attractive prospects in applications including stress distribution visualization, stress-driven light sources, and anti-counterfeiting. However, these materials generally suffer from the difficulty of achieving non-decaying ML when subjected to continuous mechanical stimulation. Herein, we develop a trap-controlled reproducible ML material, Li2MgGeO4:Mn2+, and report its short-term non-decaying ML behavior. Investigation of trap properties suggests that the unique non-decaying ML behavior should arise from the deep traps existing in Li2MgGeO4:Mn2+, which provide electron replenishment for shallow traps that release small numbers of electrons during short-term cyclic friction. Our results are expected to provide a reference for the ultimate achievement of long-term non-decaying ML in such materials.
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Anoectochilus roxburghii and Anoectochilus formasanus are the major species of genus Anoectochilus used in traditional Chinese medicine for their abundant content of flavonoids and some other medicinal constituents. In recent years, their wild resources are gradually exhausted due to over-collection and ecological deterioration. Artificial cultivation and tissue culture are employed to increase production. In this study, the open reading frame, promoter and genomic sequences of the chalcone synthase (CHS) gene were cloned from these two species according to their transcriptome information, and used for expression analysis in response to the induction of phenylalanine, ultraviolet light and NaCl, and its effect investigation on accumulation of flavonoids. The results showed that the expression of the CHS genes was upregulated in response to these inductions and resulted in increasing accumulation of total flavonoids. However, the increased flavonoids induced by phenylalanine and ultraviolet light were mainly allocated into the anthocyanidin branch of flavonoids biosynthesis. Not only did it improved the medicinal value, but might have inhibitory effect on plant growth because of the increased malondialdehyde accumulation. Under the induction of appropriate concentration of NaCl, the medicinal constituents of flavonoids were increased without inhibition to plant growth.
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Aciltransferasas/genética , Aciltransferasas/metabolismo , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas , Plantas Medicinales/genética , Plantas Medicinales/metabolismo , Aciltransferasas/química , Secuencia de Aminoácidos , Clonación Molecular , FilogeniaRESUMEN
Regulating fluorescence lifetime of lanthanide nanocomposites is highly desired for optical multiplexing applications, for instance, security printing, anticounterfeiting, and data storage. Herein, sensitive fluorescence lifetime tuning in nanocomposite fibers is reported which are composed of silica-coated gold nanorods assembled in Eu-polystyrene nanofibers. The prepared nanofibers possess unique properties of tunable fluorescence lifetime and distinct textured patterns together with superior flexibility and superhydrophobicity. In a single 612 nm emission channel, over ten different populations of fluorescence lifetime from the range of 322-551 µs are harvested. Thanks to the tunable fluorescence lifetime and different textured patterns, a security pattern to demonstrate optical multiplexing applications is designed. The security pattern hides the real information of "69" in a noticeable scene that shows fake information "8" under UV radiation or "13" by only watching their pattern structures.
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Nanofibras/química , Polímeros/química , Nanofibras/ultraestructura , Nanotubos/química , Nanotubos/ultraestructura , Espectrometría de Fluorescencia , Rayos UltravioletaRESUMEN
OBJECTIVE: To determine the risk factors and develop a risk score model for the textbook outcome(TO)among patients undergoing curative-intent resection of intrahepatic cholangiocarcinoma(ICC).METHODS: Theclinicopathological data of 261 ICC patients between January 2011 and January 2017 in Zhongda Hospital of SoutheastUniversity and No.81 Hospital of PLA undergoing partial hepatectomy were retrospectively collected. Logistic regressionanalyses were performed to determine the significant risk factors for predicting TO.RESULTS: A total of 261 patientsundergoing curative-intent resection of ICC were enrolled in the study. Among them,TO was achieved in 67 patients(25.7%). A multivariable logistic regression analysis indicated that older age,non-cirrhosis,reduced operative duration,and T1 a stage disease were independently associated with achieving a TO. A risk score to assess the probability of TOwas developed according the above four risk factors and had good accuracy and satisfactory calibration(χ~2=1.350,P=0.853).CONCLUSION: Younger ICC patients with short operation duration,no cirrhosis,and tumor diameter <5 cm mayhave the higher probability to achieve TO. The risk score model could accurately predict postoperative TO of patientswith ICC.
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Optical characteristics of luminescent materials, including emission color (wavelength), lifetime, and excitation mode, play crucial roles in data communication and information security. Conventional luminescent materials generally display unicolor, unitemporal, and unimodal (occasionally bimodal) emission, resulting in low-level readout and decoding. The development of multicolor, multitemporal, and multimodal luminescence in a single material has long been considered to be a significant challenge. In this study, for the first time, the superior integration of colorful (red-orange-yellow-green), bitemporal (fluorescent and delayed), and four-modal (thermo-/mechano-motivated and upconverted/downshifted) emissions in a particular piezoelectric particle via optical multiplexing of dual-lanthanide dopants is demonstrated. The as-prepared versatile NaNbO3 :Pr3+ ,Er3+ luminescent microparticles shown are particularly suitable for embedding into polymer films to achieve waterproof, flexible/wearable and highly stretchable features, and synchronously to provide multidimensional codes that can be visually read-out using simple and commonly available tools (including the LED of a smartphone, pen writing, cooling-heating stimuli, and ultraviolet/near-infrared lamps). These findings offer unique insight for designing highly integrated stimuli-responsive luminophors and smart devices toward a wide variety of applications, particularly advanced anticounterfeiting technology.
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Spontaneous exchange bias (SEB) under zero field cooling (ZFC) has recently attracted lots of attention due to its underlying physics and potential applications. Here we report the giant SEB (GSEB) of SmFeO3 single crystals by tuning magnetic compensation by temperature, which is rather convenient. A SEB field of up to 1 T at 3.9 K after ZFC (-1.4 T at 3.9 K after field cooling) was obtained. The SEB shows reciprocal relationship with remnant magnetization.
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A variety of up-and-coming applications of piezoluminescence in artificial skins, structural health diagnosis, and mechano-driven lightings and displays recently have triggered an intense research effort to design and develop new piezoluminescent materials. In this work, we deduced and verified an efficient piezoluminescence in ferroelectric Ca3Ti2O7:Pr3+ long-persistent phosphor, in view of three fundamental elements forming piezoluminescence - piezoelectricity, luminescent centers and carrier traps. Under the stimulation of mechanical actions including compression and friction, Ca3Ti2O7:Pr3+ shows an intense red emission from 1D2-3H4 transition of Pr3+. On the basis of investigations on structural and optical characteristics especially photoluminescence, persistent luminescence and thermoluminescence, we finally proposed a possible piezoluminescent mechanism in Ca3Ti2O7:Pr3+. Our research is expected to expand the horizon of existing piezoluminescent materials, accelerating the development and application of new materials.
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We investigated the properties of alternating current (AC)-driven electroluminescence from (Ba0.4Ca0.6)TiO3:Pr3+ diphase polycrystal-based device. The results of crystal phases and micrographs, and the symmetrical dual emissions in one AC cycle, indicate the spontaneous formation of a dielectric/phosphor/dielectric sandwich microstructure in (Ba0.4Ca0.6)TiO3:Pr3+. The electroluminescent device emits a red light of 617 nm, which is attributed to the ¹D2-³H4 transition of Pr3+ in the phosphor phase. At a fixed AC frequency, the intensity of electroluminescence exhibits a steep enhancement when applying an increased driving electric field that is beyond a threshold. In a fixed driving electric field, the intensity of electroluminescence shows a rapid rise at low frequencies, but reaches saturation at high frequencies. Based on a double-injection model, we discussed systematically the electroluminescent processes in a whole cycle of AC electric field, which matched well with the experimental data. Our investigation is expected to expand our understanding of such a diphase electroluminescent device, thereby promoting their applications in lighting and displays.
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Self-activated phosphors are capable of generating optical emissions from the internal ion groups of host lattice before externally introducing luminescent ions. However, numerous self-activated phosphors only show luminescence at low temperature due to the thermally activated energy migration among ion groups at room temperature, severely confining their application conditions. In this letter, we propose a strategy to converting the low-temperature luminescence to a room-temperature one through changing the synthesis conditions to induce structural distortions and thus to limit energy migration. Room-temperature self-activated luminescence of Ca2 Nb2 O7 was accordingly achieved in submicroplates synthesized using the sol-gel method. By further coupling the blue broadband emission from Ca2 Nb2 O7 submicroplates with the characteristic luminescence of Ln3+ (Pr3+ , Sm3+ , and Dy3+ ) dopants, multicolor emissions were successively tuned through adjusting the concentration of Ln3+ . Our results are expected to expand the scope of designing room-temperature self-activated phosphors and tuning multicolor emission.
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Colorful nanofibrous membranes have attracted much attention for their visual varieties and various functionalities. In this article, a colored solution electrospinning process was used to fabricate colorful hydrophobic poly(vinyl butyral) (PVB)/cationic dye nanofibrous membranes (NFMs) successfully. The color and morphology of these as-spun nanofibrous membranes have been analyzed by colorimetry, spectroscopy, and scanning electron microscopy (SEM). It is shown that the as-spun colorful PVB-based membranes exhibit excellent level-dyeing property and color stability. Furthermore, the doping of cationic dye and the increase of dye concentration can decrease the diameter of the as-spun colored fibers, which results in better level-dyeing property and higher water contact angle more than 140°. The stained PVB fibrous membranes with excellent level-dyeing property and hydrophobicity are promising in some applications such as textiles, wallpapers, and anticorrosive coating/painting.
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CdS is one of the important II-VI group semiconductors. In this paper, the electrical transport behavior of an individual CdS microrope composed of twisted nanowires is studied. It is found that the current-voltage (I-V) characteristics show two distinct power law regions from 360 down to 60 K. Space-charge-limited current (SCLC) theory is used to explain these temperature- and electric-field-dependent I-V curves. The I-V data can be well fitted by this theory above 100 K, and the corresponding carrier mobility, trap energy, and trap concentration are also obtained. However, the I-V data exhibit some features of the Coulomb blockade effect below 80 K.
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A conventional electrospinning setup cannot work without a plug (electricity supply). In this article, we report a self-powered electrospinning setup based on a hand-operated Wimshurst generator. The new device has better applicability and portability than a typical conventional electrospinning setup because it is lightweight and can work without an external power supply. Experimental parameters of the apparatus such as the minimum number of handle turns to generate enough energy to spin, rotation speed of the handle and electrospinning distance were investigated. Different polymers such as polystyrene (PS), poly(vinylidene fluoride) (PVDF), polycaprolactone (PCL) and polylactic acid (PLA) were electrospun into ultrathin fibers successfully by this apparatus. The stability, reliability, and repeatability of the new apparatus demonstrate that it can be used as not only a demonstrator for an electrospinning process, but also a beneficial complement to conventional electrospinning especially where or when without a power supply, and may be used in wound healing and rapid hemostasis, etc.