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1.
Adv Mater ; : e2310831, 2024 Mar 30.
Article in English | MEDLINE | ID: mdl-38553988

ABSTRACT

0D Bi-based 329-type halide perovskite is demonstrated as a promising semiconductor for X-ray detection due to its strong X-ray absorption, superior stability, availability of large single crystals (SCs) and solution processibility at low temperature. However, its low mobility-lifetime product (µτ) limits its further improvement in detection sensitivity. Based on the first-principles calculations, this work designs a new 2D Bi-based 329-type halide perovskite using a mixed-halide-induced structural dimension regulation strategy. By using a continuous supply of a precursor solution, this work successfully grows inch-sized high-quality SCs. These SCs exhibit large µτ product, high resistivity, and low ion migration. The detectors fabricated using the SCs show X-ray detection sensitivity as high as 24,509 µC Gyair -1 cm-2, short response time of 315 µs, low detection limit of 4.3 nGy s-1, and superior stability. These properties are the best among all lead-free perovskite detectors and are comparable to those of the best lead-based perovskite detectors. The linear array detector assembled on the SCs for the first time also shows a high spatial resolution of 10.6 lp mm-1 during X-ray imaging. The high performance combined with superior stability of these new 329-type lead-free halide perovskite SCs is expected to promote a new generation of X-ray detection technologies.

2.
Adv Mater ; 36(3): e2305513, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37878999

ABSTRACT

Metal halide perovskite single crystals (MHP-SCs) are known for their facile fabrication into large sizes using inexpensive solution methods. Owing to their combination of large mobility-lifetime products and strong X-ray absorption, they are considered promising materials for efficient X-ray detection. However, they suffer from large dark currents and severe ion migration, which limit their sensitivity and stability in critical X-ray detection applications. Herein, a heterointerface design is proposed to reduce both the dark current and ion migration by forming a heterojunction. In addition, the carrier transport performance is significantly improved using heterointerface engineering by designing a gradient band structure in the SCs. The SC heterojunction detectors exhibit a high sensitivity of 3.98 × 105 µC Gyair -1 cm-2 with a low detection limit of 12.2 nGyair s-1 and a high spatial resolution of 10.2 lp mm-1 during imaging. These values are among the highest reported for state-of-the-art MHP X-ray detectors. Moreover, the detectors show excellent stability under continuous X-ray irradiation and maintainclear X-ray imaging after 240 d. This study provides novel insights into the design and fabrication of X-ray detectors with high detection efficiency and stability, which are beneficial for developing inexpensive, high-resolution X-ray imaging equipment.

3.
World J Gastroenterol ; 29(43): 5818-5833, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-38074915

ABSTRACT

BACKGROUND: Patients with inflammatory bowel diseases (IBDs) generally have poor knowledge, attitude, and practice of their disease, while the data from China are lacking. AIM: To address this knowledge disparity among Chinese patients with IBD. METHODS: This web-based, cross-sectional study was conducted on a cohort of IBD patients who visited the Second Affiliated Hospital of Wenzhou Medical University between December 2022 and February 2023. Their socio-demographic information and the knowledge, attitude, and practice scores were collected and estimated using a self-designed questionnaire. Pearson's correlation analysis was used to determine the pairwise correlations among knowledge, attitude, and practice scores. A multivariate logistic regression analysis was further performed to determine the independent factors associated with their knowledge, attitude, and practice scores. RESULTS: A total of 353 patients (224 males) with IBD completed the questionnaires. The mean knowledge, attitude, and practice scores were 10.05 ± 3.46 (possible range: 0-14), 41.58 ± 5.23 (possible range: 0-56), 44.20 ± 7.39 (possible range: 0-56), respectively, indicating good knowledge, positive attitude, and proactive practice toward IBD. Pearson's correlation analysis showed that the knowledge score had significant positive correlations with the attitude score (r = 0.371, P < 0.001) and practice score (r = 0.100, P < 0.001). The attitude score had a significant positive correlation with the practice score (r = 0.452, P < 0.001). Moreover, multivariate logistic regression analysis showed that aged 30-40 years [odds ratio (OR) = 4.06, 95% confidence interval (CI): 1.04-15.82, P = 0.043], middle school education (OR = 3.98, 95%CI: 1.29-12.33, P = 0.017), high school/technical secondary school education (OR = 14.06, 95%CI: 3.92-50.38, P < 0.001), and junior college/bachelor's degree and above education (OR = 15.20, 95%CI: 4.15-55.650, P < 0.001) were independently associated with good knowledge. The higher knowledge score was independently associated with a positive attitude (OR = 1.23, 95%CI: 1.11-1.36, P < 0.001). The higher attitude score was independently associated with proactive practice (OR = 1.20, 95%CI: 1.11-1.30, P < 0.001). CONCLUSION: Chinese patients with IBD might have good knowledge, a positive attitude, and proactive practice toward their disease. However, a small number of specific items require education.


Subject(s)
Health Knowledge, Attitudes, Practice , Inflammatory Bowel Diseases , Male , Humans , Cross-Sectional Studies , Inflammatory Bowel Diseases/therapy , Educational Status , Surveys and Questionnaires
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 41(4): 443-449, 2023 Aug 01.
Article in English, Chinese | MEDLINE | ID: mdl-37474477

ABSTRACT

OBJECTIVES: To investigate the effect of different soft-tissue morphologies on the treatment of skeletal class Ⅰ malocclusion patients by analyzing measurement data before and after treatment. METHODS: Pre- and post-treatment lateral cephalograms of 55 adult female Angle class Ⅰ patients were collected in the Department of Orthodontics, Hospital of Stomatology, Jilin University from January 2012 to December 2020. Chin soft-tissue morphologies in the lateral cranial radiographs were used to divide the patients into an abnormal chin morphology group (flat and retracted chins, n=27) and a normal chin morphology group (rounded and prominent chins, n=28). Relevant soft- and hard-tissue indexes were selected to study in-group varieties and intergroup differences in the varying chin morphologies before and after treatment. RESULTS: The chin-lip angle, mandibular chin angle, mandibular chin vertex angle, PP-MP, LL-E, UL-E, Po-Pos, and B-B' thickness in the abnormal chin morphology group were significantly higher than those in the normal chin morphology group (P<0.05). Furthermore, m∶BMe and n∶B'Mes in the abnormal chin morphology group were signi-ficantly lower than those in the normal chin morphology group (P<0.05). After treatment, the mandibular chin angle, mandibular chin vertex angle, U1-SN, L1-MP, LL-E, UL-E, SNA, SNB, and B-B' thickness of the abnormal chin morphology group significantly decreased (P<0.05), whereas the nasolabial angle, m∶BMe, n∶B' Mes, and Po-Pos significantly increased (P<0.05). In the normal chin morphology group, the U1-SN, L1-MP, LL-E, UL-E, and B-B' thicknesses decreased significantly (P<0.05), whereas the nasolabial angle significantly increased (P<0.05). Among them, m∶BMe and n∶B' Mes were positively correlated. CONCLUSIONS: Chin morphology affects the formulation of treatment plans. Compared with the normal chin morphology group, the abnormal chin morphology group required a larger retraction of incisors. Although the chin of soft-tissue morphology is related to the morphology of bones, the changes in soft tissue chin after treatment cannot be directly predicted according to the bone changes. Soft-tissue chin morphology affects the aesthetic assessment of the soft-tissue lateral profile and the change in soft tissue before and after treatment. The method of predicting the change in soft-tissue chin after treatment should consider the morphology of the soft-tissue chin.


Subject(s)
Esthetics, Dental , Lip , Adult , Humans , Female , Chin , Cephalometry/methods , Mandible
5.
Article in English | MEDLINE | ID: mdl-37027685

ABSTRACT

Beyond high accuracy, good interpretability is very critical to deploy a face forgery detection model for visual content analysis. In this paper, we propose learning patch-channel correspondence to facilitate interpretable face forgery detection. Patch-channel correspondence aims to transform the latent features of a facial image into multi-channel interpretable features where each channel mainly encoders a corresponding facial patch. Towards this end, our approach embeds a feature reorganization layer into a deep neural network and simultaneously optimizes classification task and correspondence task via alternate optimization. The correspondence task accepts multiple zero-padding facial patch images and represents them into channel-aware interpretable representations. The task is solved by step-wisely learning channel-wise decorrelation and patch-channel alignment. Channel-wise decorrelation decouples latent features for class-specific discriminative channels to reduce feature complexity and channel correlation, while patch-channel alignment then models the pairwise correspondence between feature channels and facial patches. In this way, the learned model can automatically discover corresponding salient features associated to potential forgery regions during inference, providing discriminative localization of visualized evidences for face forgery detection while maintaining high detection accuracy. Extensive experiments on popular benchmarks clearly demonstrate the effectiveness of the proposed approach in interpreting face forgery detection without sacrificing accuracy. The source code is available at https://github.com/Jae35/IFFD.

6.
Adv Mater ; 35(18): e2211977, 2023 May.
Article in English | MEDLINE | ID: mdl-36802105

ABSTRACT

Lead-free A3 Bi2 I9 -type perovskites are demonstrated as a class of promising semiconductors for high-performance X-ray detection due to their high bulk resistivity and strong X-ray absorption, as well as reduced ion migration. However, due to their long interlamellar distance along their c-axis, their limited carrier transport along the vertical direction is a bottleneck for their detection sensitivity. Herein, a new A-site cation of aminoguanidinium (AG) with all-NH2 terminals is designed to shorten the interlayer spacing by forming more and stronger NH···I hydrogen bonds. The prepared large AG3 Bi2 I9 single crystals (SCs) render shorter interlamellar distance for a larger mobility-lifetime product of 7.94 × 10-3  cm2  V-1 , which is three times higher than the value measured on the best MA3 Bi2 I9 SC (2.87 × 10-3  cm2  V-1 ). Therefore, the X-ray detectors fabricated on the AG3 Bi2 I9 SC exhibit high sensitivity of 5791 uC Gy-1  cm-2 , a low detection limit of 2.6 nGy s-1, and a short response time of 690 µs, all of which are far better than those of the state-of-the-art MA3 Bi2 I9 SC detectors. The combination of high sensitivity and high stability enables astonishingly high spatial resolution (8.7 lp mm-1 ) X-ray imaging. This work will facilitate the development of low-cost and high-performance lead-free X-ray detectors.

7.
Am J Emerg Med ; 38(8): 1568-1571, 2020 08.
Article in English | MEDLINE | ID: mdl-31493981

ABSTRACT

BACKGROUND: Emergency department (ED) visits associated with prescription opioids have increased in the last ten years. This study describes the opioid utilization of patients discharged from the ED with an opioid prescription for pain, 14 to 21 days post discharge. METHODS: This is a prospective, single-centered, survey-based observational descriptive study conducted from December 2017 to February 2018 in the ED at a tertiary level 1 trauma center. The primary outcomes were the percentage of patients with unused opioids and the quantity of opioids remaining 14 to 21 days post ED discharge. A sample of ED patients who received an oral opioid prescription were approached for informed consent and received a telephone survey 14 to 21 days post discharge. RESULTS: Of 178 patients approached for consent, 122 were enrolled. Among them, 98 were successfully surveyed (80.3%). The median number of pills prescribed was 8 (IQR:8-12). Nearly half (49%) of patients had unused opioids 14 to 21 days post ED discharge, not including 9.2% of patients who never filled their prescriptions. Of the total 980 pills prescribed, 327 pills remained unused (33.4%). Only 55.1% of patients reported receiving counseling on side effect of opioids and 21.4% of patients reported they received counseling on storage and disposal. CONCLUSION: The majority of patients in this study had unused or unfilled opioids 14 to 21 days post ED discharge, and approximately one third of the opioids prescribed remained unused. Most patients did not recall receiving opioid related education including proper disposal of medication.


Subject(s)
Analgesics, Opioid/therapeutic use , Emergency Service, Hospital , Patient Discharge , Administration, Oral , Analgesics, Opioid/administration & dosage , Drug Storage , Female , Humans , Male , Middle Aged , Practice Patterns, Physicians'/statistics & numerical data , Prospective Studies , Refuse Disposal
8.
J Phys Chem Lett ; 11(2): 541-547, 2020 Jan 16.
Article in English | MEDLINE | ID: mdl-31887063

ABSTRACT

Developing integrable, nanoscale, and low-energy-consumption lasers is a crucial step toward on-chip optical communications and computing technologies. The strong exciton-photon interaction that emerged in monolayer transition metal dichalcogenides (TMDs) holds promise for engineering and integration. Herein, we prepare the MoSe2/microsphere cavities excitonic lasers by placing SiO2 microspheres on top of a monolayer MoSe2 film. By virtue of continuous-wave exciting MoSe2/microsphere whispering gallery mode (WGM) cavities, we realize multiple excitonic WGM lasing in the emission wavelength range of ∼750-875 nm at room temperature with tunable properties of free spectral range (FSR) and full width at half-maximum (fwhm) by varying the microsphere size. Theoretical calculations based on the finite element method (FEM) using COMSOL software were utilized to identify lasing modes and reveal the corresponding electric field distribution. These findings help to deepen fundamental understanding of excitonic WGM lasing and provide a promising research platform for integrable, scalable, and low-cost laser devices.

9.
Life Sci ; 222: 29-35, 2019 Apr 01.
Article in English | MEDLINE | ID: mdl-30826495

ABSTRACT

Recently, several plexins and semaphorins have been associated with osteoclastogenesis, a vital process for bone remodeling. Plexin-A2 is implicated in bone homeostasis, however, whether it plays a role in osteoclastogenesis and the underlying mechanism remain unknown. We show that plexin-A2 expression is upregulated during RANKL-induced osteoclastogenesis. In addition, the soluble Sema6A fused with IgG1 Fc region (Fc-Sema6A) interacts with plexin-A2 from cell lysates of osteoclasts, suggesting that plexin-A2 acts as a receptor of Sema6A in osteoclasts. Moreover, Sema6A treatment stimulates RANKL-induced osteoclastogenesis, and this effect is abolished when plexin-A2 is neutralized, which illustrates an indispensable role of plexin-A2 in mediating Sema6A effect on osteoclastogenesis. Mechanistically, Sema6A-plexin-A2 axis enhances RANKL-induced activation of PLCγ as well as downstream target NFATc1, one master transcriptional factor of osteoclastogenesis. Lastly, inhibition of PLCγ by pharmacological inhibitor U73122 abrogates Sema6A-stimulated NFATc1 activation and RANKL-induced osteoclastogenesis, thus demonstrating that the PLCγ-mediated NFATc1 activation accounts for the promotive role of Sema6A-plexin-A2 axis in RANKL-induced osteoclastogenesis. Taken together, this study uncovers a novel role of Sema6A and plexin-A2 in osteoclastogenesis, and also offers them as possible therapeutic targets in the intervention of osteolytic diseases.


Subject(s)
NFATC Transcription Factors/metabolism , Nerve Tissue Proteins/metabolism , Osteogenesis/physiology , Phospholipase C gamma/metabolism , RANK Ligand/metabolism , Receptors, Cell Surface/metabolism , Semaphorins/metabolism , Animals , Cell Differentiation/drug effects , Cell Differentiation/physiology , Cells, Cultured , Estrenes/pharmacology , Mice , Mice, Inbred C57BL , Nerve Tissue Proteins/pharmacology , Osteoclasts/drug effects , Osteoclasts/metabolism , Osteogenesis/drug effects , Phosphodiesterase Inhibitors/pharmacology , Phospholipase C gamma/antagonists & inhibitors , Pyrrolidinones/pharmacology , Semaphorins/pharmacology
10.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(7): 2178-82, 2016 Jul.
Article in Chinese | MEDLINE | ID: mdl-30035973

ABSTRACT

In order to reveal the mechanism of LLLI accelerating teeth moving, we investigated the changes of alkaline phosphatase and intracellular calcium concentration when osteoblasts under stress were subjected low-level-laser-irradiation (LLLI). MG-63 cells were divided into four groups: control group, stress group, LLLI group and LLLI-stress group. Osteoblasts were subjected to the mechanical stress by a four-point bending system at 0.5 Hz and 3 000 µstrain. The secretions of ALP of each group are measured by spectrophotometer. In the second part, MG-63 cells were divided into two groups: stress group and LLLI-stress group. We checked intracellular calcium concentration via FCM and fluorescent indicator fluo-3/AM at 0, 5, 15, 30 and 60 min under stress. LLLI- stress group will receive LLLI for 1 min after stress. Compared to a control group, increased ALP secretions were observed in the other three groups. But ALP secretions in LLLI-stress group were lower than stress group and LLLI group. THE changing curve of intracellular calcium concentration in laser-stress groups is gentle instead of "jumping" in stress group. Proper stress, LLLI and combined application of these two can increase the secretions of ALP in osteoblasts compared to the control group. But the secretions of ALP decreased when combined application of stress and LLLI compared to using alone. LLLI can regulate the changing rhythm of concentration of the intracellular calcium to promote proliferation of MG-63 cell under stress, which means LLLI can reduce the bone-formation of osteoblasts under stress.


Subject(s)
Osteoblasts , Stress, Mechanical , Alkaline Phosphatase , Calcium , Cell Proliferation , Cytoplasm
11.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 43(1): 21-5, 2008 Jan.
Article in Chinese | MEDLINE | ID: mdl-18380969

ABSTRACT

OBJECTIVE: To investigate the effect of systematic administration of simvastatin on the bone morphogenetic protein-2 (BMP-2) expression in the periodontal tissue after rat tooth movement and on the relapse of tooth movement. METHODS: Orthodontic tooth movement of upper first molar was performed in 32 rats with coil spring for 21 days. The 32 rats were randomly allocated into 4 groups: negative control group (isotonic saline) and three experimental groups (2.5 mg x kg(-1), 5.0 mg x kg(-1) and 10.0 mg x kg(-1)). The simvastatin started to be administered to the experimental groups 1 day before appliances were removed, and once a day there after for 4 weeks. The negative control group received the isotonic saline only. The interdental distance between the first and second maxillary molars were measured, when appliances were removed, and 1 week and 4 weeks after that. After the rats were sacrificed, sections of first maxillary molar and periodontal tissue were studied by immunohistochemistry. RESULTS: The number and percentage of relapse was lower in the three experimental groups than in the negative control group (P < 0.05, P < 0.01). The lower dose was given, the less relapse there was, with the lowerest dose resulting in lowest percentage of relapse (26.81% and 53.38%). BMP-2 expression in experimental groups was higher than in the negative control group, with the lowerest dose group showing the highest expression (P < 0.001). The BMP-2 expression on the tension side was slightly stronger than that on the compression side (P > 0.05). CONCLUSIONS: Systemic administration of simvastatin could decrease the extent of relapse of the orthodontic-moved tooth in rat, and the lower-dose of simvastatin seemed more effective. The possible mechanism for this may be that simvastatin functions by increasing the expression of BMP-2 in the periodontal tissue, accelerating the osteoblast activity and promoting bone formation.


Subject(s)
Bone Morphogenetic Protein 2/metabolism , Periodontium/drug effects , Periodontium/metabolism , Simvastatin/pharmacology , Tooth Movement Techniques , Animals , Male , Rats , Rats, Wistar
12.
Shanghai Kou Qiang Yi Xue ; 16(5): 507-11, 2007 Oct.
Article in Chinese | MEDLINE | ID: mdl-18004482

ABSTRACT

PURPOSE: To perform qualitative and quantitative analyses of core binding factor alpha1 (cbfalpha1) in periodontal tissue during the experimental rat tooth movement process and to investigate the active mechanism of cbfalpha1 in the osteoblast differentiation. METHODS: 42 male Wistar rats aged 8 weeks were divided into 7 groups (0,1,3,5,7,10 and 14 days groups) in random, 6 rats in each group. 42 rats were perfused and sacrificed at the 1st, 3rd, 5th, 7th, 10th and 14th day. All specimens were fixed, then proceeded with HE and cbfalpha1 immunohistochemical staining. The results were analyzed by SPSS11.0 software package for Dunnett test, and the histological changes of cbfalpha1 in periodontal tissue were evaluated. RESULTS: In the periodontal ligament(PDL) of non orthodontic treatment group, the expression of cbfalpha1 was lower; the expression of cbfalpha1 in every experimental groups increased firstly and decreased later; the expression of cbfalpha1 in the surface of the alveolar bone was lower in the compression side than in the tension side, and the number of positive cells was less too (P<0.01). CONCLUSION: cbfalpha1 participates in the process of bone remodeling during the process of orthodontic tooth movement, and it promotes the remodeling and stability of PDL.


Subject(s)
Bone Remodeling , Core Binding Factor alpha Subunits/metabolism , Tooth Movement Techniques , Animals , Male , Osteoclasts , Periodontal Ligament , Periodontium , Rats , Rats, Wistar
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