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1.
Methods ; 222: 51-56, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184219

RESUMO

The interaction between human microbes and drugs can significantly impact human physiological functions. It is crucial to identify potential microbe-drug associations (MDAs) before drug administration. However, conventional biological experiments to predict MDAs are plagued by drawbacks such as time-consuming, high costs, and potential risks. On the contrary, computational approaches can speed up the screening of MDAs at a low cost. Most computational models usually use a drug similarity matrix as the initial feature representation of drugs and stack the graph neural network layers to extract the features of network nodes. However, different calculation methods result in distinct similarity matrices, and message passing in graph neural networks (GNNs) induces phenomena of over-smoothing and over-squashing, thereby impacting the performance of the model. To address these issues, we proposed a novel graph representation learning model, dual-modal graph learning for microbe-drug association prediction (DMGL-MDA). It comprises a dual-modal embedding module, a bipartite graph network embedding module, and a predictor module. To assess the performance of DMGL-MDA, we compared it against state-of-the-art methods using two benchmark datasets. Through cross-validation, we illustrated the superiority of DMGL-MDA. Furthermore, we conducted ablation experiments and case studies to validate the effective performance of the model.


Assuntos
Benchmarking , Redes Neurais de Computação , Humanos , Projetos de Pesquisa
2.
Skin Res Technol ; 29(1): e13269, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36704881

RESUMO

BACKGROUND: Acne is the eighth-most prevalent inflammatory skin disease with no optimal treatment. Photodynamic therapy (PDT) is an effective treatment for severe acne. AIMS: The effect of PDT on the composition and diversity of skin microflora in severe acne patients was studied. MATERIALS AND METHODS: A total of 18 patients with severe acne and 8 healthy individuals were selected for this study. Patients were treated with 5-aminolevulinic acid-mediated PDT once a week three times in total; the skin microbiome was measured by 16S ribosomal RNA gene sequencing before and after treatment (1 week after each PDT). RESULTS: The microflora composition was different between healthy controls and patients, and between patients before and after treatment. Alpha diversity indices were lower in patients than those in control. There were 15 bacterial genera with high relative abundance that had noticeable changes during treatment. At the genus level,particularly Cutibacterium acnes (C. acnes formerly Propionibacterium acnes), there was no statistically significant difference among different group. The abundances of Staphylococcus epidermidis and Staphylococcus aureus were low. DISCUSSION: The microbial composition is different between severe acne patients acne patients and healthy individuals. The therapeutic efficacy of severe acne treated with PDT is associated with the composition and diversity of skin microbiota. CONCLUSION: The skin microbial composition changes after PDT treatment. PDT is an effective method for the treatment of severe acne.


Assuntos
Acne Vulgar , Microbiota , Fotoquimioterapia , Humanos , Acne Vulgar/tratamento farmacológico , Pele/microbiologia , Ácido Aminolevulínico/uso terapêutico , Ácido Aminolevulínico/farmacologia , Propionibacterium acnes/genética , Fotoquimioterapia/efeitos adversos
3.
Sensors (Basel) ; 23(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37430779

RESUMO

Reversible data hiding in encrypted images (RDH-EI) is instrumental in image privacy protection and data embedding. However, conventional RDH-EI models, involving image providers, data hiders, and receivers, limit the number of data hiders to one, which restricts its applicability in scenarios requiring multiple data embedders. Therefore, the need for an RDH-EI accommodating multiple data hiders, especially for copyright protection, has become crucial. Addressing this, we introduce the application of Pixel Value Order (PVO) technology to encrypted reversible data hiding, combined with the secret image sharing (SIS) scheme. This creates a novel scheme, PVO, Chaotic System, Secret Sharing-based Reversible Data Hiding in Encrypted Image (PCSRDH-EI), which satisfies the (k,n) threshold property. An image is partitioned into N shadow images, and reconstruction is feasible when at least k shadow images are available. This method enables separate data extraction and image decryption. Our scheme combines stream encryption, based on chaotic systems, with secret sharing, underpinned by the Chinese remainder theorem (CRT), ensuring secure secret sharing. Empirical tests show that PCSRDH-EI can reach a maximum embedding rate of 5.706 bpp, outperforming the state-of-the-art and demonstrating superior encryption effects.

4.
Opt Lett ; 47(3): 730-733, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35103719

RESUMO

Interferometric fiber optic gyroscopes are widely used in spacecraft, navigation, and autopilot and missile systems due to their high accuracy and fast speed. However, the dynamic measurement range is generally limited to a small value. In this paper, an angular velocity measurement system based on a dual-comb Sagnac interferometer is proposed. The theoretical dynamic range can reach the order of 108 deg/s, which is remarkably superior to that of the conventional fiber optic gyroscopes. To the best of our knowledge, this is the first demonstration of a dual-comb-based passive fiber optic gyroscope system, offering an attractive tool for measuring angular velocity with large dynamic range.

5.
Sensors (Basel) ; 22(18)2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36146178

RESUMO

Dual-comb ranging (DCR) is an important method in absolute distance ranging because of its high precision, fast acquisition rate, and large measuring range. DCR needs to obtain precise results during distance measurements for a mobile target. However, the non-ambiguity range (NAR) is a challenge when pushing the dual-comb ranging to the industry field. This paper presents a solution for extending NAR by designing an algorithm and realizing it on a field-programmable gate array (FPGA). The algorithm is robust when facing the timing jitter in the optical frequency comb. Without averaging, the Allan deviation of the results in 1 ms is ∼3.89 µm and the Allan deviation of the results is ∼0.37 µm at an averaging time of 100 ms when the target object is standstill near the NAR. In addition, several ranging experiments were conducted on a mobile target whose speed was from ∼5 mm/s to ∼10 mm/s. The experimental results verify the effectiveness and robustness of our design. The implemented design is an online and real-time data processing unit that shows great industrial potential for using the DCR system.

6.
Opt Express ; 29(4): 6271-6281, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33726152

RESUMO

Dual-comb spectroscopy (DCS) is an emerging and promising spectrometric technique with high resolution, high sensitivity, broad spectral range, and fast acquisition speed. For the recovery of the information encoded on comb modes without resolution loss, two continuous wave lasers are commonly utilized as optical intermedia to track the real-time jitter of dual-comb interferograms. This paper presents a simplified error correction method based on single optical intermedium for quasi-free-running fiber DCS. This method combines the strengths of conventional optical referencing and self-referencing error correction. We acquired whole P branch H13C14N transmittance spectra in the near infrared as a demonstration. In contrast to that of conventional dual intermedium error correction, the standard deviation of our method was merely 0.01 over the 4 THz spectral range. Our method provides a balanced and practical postprocessing routine for high-performance mode-resolved DCS applications.

7.
Opt Lett ; 46(13): 3243-3246, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197426

RESUMO

In this Letter, we demonstrate a passive all-fiber pulse delay method for repetition rate multiplication of dual-comb spectroscopy. By combining a cascaded Mach-Zehnder interferometer and digital error correction, a mode-resolved spectrum with improved acquisition speed and sensitivity can be obtained. This technique has the strengths of compact, broadband, high energetic efficiency, and low complexity. Due to the use of an adaptive post-processing algorithm, sophisticated closed-loop feedback electronics are not required, which provides a simple and effective scheme to break through the physical limitation of the repetition frequency of the frequency comb for phase-stable dual-comb applications.

8.
Med Sci Monit ; 27: e929890, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33750753

RESUMO

BACKGROUND Heterotopic ossification (HO) is a major complication after cervical disc arthroplasty (CDR) that has attracted the attention of spine surgeons. There remains a great deal of controversy regarding the surgical risk factors. The present study investigated the correlation between insufficient sagittal coverage of the prosthesis-endplate and HO after CDR and explored strategies to prevent it. MATERIAL AND METHODS We included 73 patients who underwent Prestige-LP arthroplasty. Patients were divided into HO and non-HO groups. Related data, including radiological, clinical information, were collected. HO was graded using the McAfee classification. Analysis was performed to correlate HO to the surgical segmental range of motion (ROM) at last follow-up. To evaluate the insufficient sagittal coverage of the prosthesis-endplate and other factors for developing HO, receiver operating characteristic (ROC) curves were analyzed for insufficient sagittal coverage. RESULTS Among 73 patients, 24 patients had HO at the last follow-up (HO incidence: 32.9%). The ROM in the HO group was significantly lower (P<0.001). The insufficient sagittal coverage of the upper and lower prosthesis-endplate, the height of intervertebral space, and the preoperative and postoperative ROM were related to HO (P<0.05). Multivariate logistic regression analysis showed that only insufficient sagittal coverage of the upper prosthesis-endplate was related to HO (P=0.023), and ROC curve analysis revealed that HO was more likely to occur with insufficient sagittal coverage distance ≥2.5 mm. CONCLUSIONS HO after CDR causes a reduction in ROM, the occurrence of which is associated with insufficient sagittal coverage of the prosthesis-endplate. HO was more likely to occur with insufficient sagittal coverage distance ≥2.5 mm.


Assuntos
Ossificação Heterotópica/etiologia , Substituição Total de Disco/efeitos adversos , Substituição Total de Disco/métodos , Adulto , Artroplastia/efeitos adversos , Vértebras Cervicais/cirurgia , Feminino , Humanos , Disco Intervertebral/cirurgia , Masculino , Pessoa de Meia-Idade , Pescoço/cirurgia , Ossificação Heterotópica/diagnóstico por imagem , Ossificação Heterotópica/fisiopatologia , Implantação de Prótese , Amplitude de Movimento Articular , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
9.
Acta Biochim Biophys Sin (Shanghai) ; 53(10): 1387-1397, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34494093

RESUMO

Photodynamic therapy (PDT), which is a new method for treating tumors, has been used in the treatment of cancer. In-depth research has shown that PDT cannot completely kill tumor cells, indicating that tumor cells are resistant to PDT. Glucose regulatory protein 78 (GRP78), which is a key regulator of endoplasmic reticulum stress, has been confirmed to be related to tumor resistance and recurrence, but there are relatively few studies on the further mechanism of GRP78 in PDT. Our experiment aimed to observe the role of GRP78 in HOS human osteosarcoma cells treated with pyropheophorbide-α methyl ester-mediated photodynamic therapy (MPPα-PDT) and to explore the possible mechanism by which the silencing of GRP78 expression enhances the sensitivity of HOS osteosarcoma cells to MPPα-PDT. HOS osteosarcoma cells were transfected with siRNA-GRP78. Apoptosis and reactive oxygen species (ROS) levels were detected by Hoechst staining and flow cytometry, cell viability was detected by Cell Counting Kit-8 assay, GRP78 protein fluorescence intensity was detected by immunofluorescence, and apoptosis-related proteins, cell proliferation-related proteins, and Wnt pathway-related proteins were detected by western blot. The results showed that MPPα-PDT can induce HOS cell apoptosis and increase GRP78 expression. After successful siRNA-GRP78 transfection, HOS cell proliferation was decreased, and apoptosis-related proteins expressions was increased, Wnt/ß-catenin-related proteins expressions was decreased, and ROS levels was increased. In summary, siRNA-GRP78 enhances the sensitivity of HOS cells to MPPα-PDT, the mechanism may be related to inhibiting Wnt pathway activation and increasing ROS levels.


Assuntos
Chaperona BiP do Retículo Endoplasmático/metabolismo , Osteossarcoma/metabolismo , Osteossarcoma/terapia , Fotoquimioterapia/métodos , Porfirinas/farmacologia , Via de Sinalização Wnt/genética , Apoptose/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Chaperona BiP do Retículo Endoplasmático/genética , Humanos , Espécies Reativas de Oxigênio/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos
10.
Sensors (Basel) ; 21(3)2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33572805

RESUMO

Dual-comb spectroscopy has been an infusive spectroscopic tool for gas detection due to its high resolution, high sensitivity, and fast acquisition speed over a broad spectral range without any mechanical scanning components. However, the complexity and cost of high-performance dual-comb spectroscopy are still high for field-deployed applications. To solve this problem, we propose a simple frequency domain post-processing method by extracting the accurate position of a specific absorption line frame by frame. After aligning real-time spectra and averaging for one second, the absorbance spectrum of H13C14N gas in the near-infrared is obtained over 1.1 THz spectral range. By using this method, the standard deviation of residual error is only ~0.002, showing great agreement with the conventional correction method. In addition, the spectral resolution is improved from 13.4 GHz to 4.3 GHz compared to direct spectrum averaging. Our method does not require a specially designed common-mode suppression comb, rigorous frequency control system, or complicated computational algorithm, providing a cost-effective scheme for field-deployed Doppler-limited spectroscopy applications.

11.
J Orthop Sci ; 26(4): 622-628, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32732146

RESUMO

BACKGROUND: Bone mineral density (BMD) may be an important factor affecting the clinical outcomes after total knee arthroplasty (TKA). However, further information regarding BMD in postoperative pain relief is not present yet. This study aims to gain further insight into the predictive significance of BMD in postoperative pain relief in knee osteoarthritis (KOA) patients after TKA. METHODS: 156 KOA patients treated by TKA were included in this study. Visual analogue scale (VAS) was used to measure the pain intensity in patients within one year after TKA. The patients were divided into good pain relief group (the improvement of VAS ≥ 3) and poor pain relief group (the improvement of VAS < 3). BMD and other clinical characteristics were also collected. Logistic regression analysis and receiver operating characteristic curve (ROC curve) were used to evaluate the predictive significance of BMD. Subgroup analysis was used to compare the difference of postoperative pain between High BMD group and Low BMD group extra. RESULTS: 34 (21.8%) patients had poor pain relief after TKA. Logistic regression analysis indicated that age, BMD, preoperative hospital for special surgery (HSS) scores, preoperative VAS score and postoperative posterior slope angles (PSA) were the risk factors of poor pain relief (P < 0.05). Using BMD as a predictor, the optimum cut-off value of poor pain relief was T-level = -3.0 SD in the ROC curve, where sensitivity and specificity were 73.5% and 83.7%, respectively. Based on this cut-off value, obvious pain relief was observed in the High BMD group compared with Low BMD group from the 6th month after TKA in the subgroup analysis (P < 0.05). CONCLUSIONS: BMD is an effective predictor for postoperative pain relief in KOA patients after TKA, and the poor pain relief should be fully considered especially when BMD T-level ≤ -3.0 SD.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho , Artroplastia do Joelho/efeitos adversos , Densidade Óssea , Humanos , Articulação do Joelho , Osteoartrite do Joelho/complicações , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia
12.
Med Sci Monit ; 26: e923656, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32694499

RESUMO

BACKGROUND There remains a great deal of controversy regarding the selection of long-segment fixation and short-segment fixation, especially for degenerative scoliosis (DS) patients with Cobb angle 20°~40°. The purpose of this study was to investigate the effects of different fixation levels in DS patients with Cobb angle 20°~40°. MATERIAL AND METHODS We enrolled 96 DS patients, divided into a long-segment fixation group (>3 segments) and a short-segment fixation group (≤3 segments). The visual analogue scale (VAS) and Oswestry disability index (ODI) were used to evaluate the clinical outcomes. The spinal-pelvic parameters and complications were also collected and analyzed. RESULTS The short-segment fixation group had the advantages of less blood loss, shorter operation time and shorter fluoroscopy time (P<0.05). The 2 groups achieved similar effects in leg pain (VAS) and ODI after operation (P>0.05); however, there was a better relief of low back pain in the long-segment fixation group (P<0.05). The changes of Cobb angle, sagittal vertical axis (SVA), lumbar lordosis (LL), pelvic tilt (PT) and sacral slope (SS) in the long-segment fixation group were more obvious than that in the short-segment fixation group at the final follow-up (P<0.05). The prevalence of complications in the long-segment fixation group was significantly higher than in the short-segment fixation group (P<0.01). CONCLUSIONS Short-segment fixation has less surgical trauma and fewer complications, whereas long-segment fixation has more advantages in improving spine-pelvis parameters and relieving low back pain.


Assuntos
Escoliose/cirurgia , Fusão Vertebral/métodos , Idoso , Feminino , Humanos , Dor Lombar , Vértebras Lombares/cirurgia , Masculino , Pessoa de Meia-Idade , Medição da Dor , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento
13.
Entropy (Basel) ; 22(7)2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-33286491

RESUMO

The gender ratio of free-range chickens is considered as a major animal welfare problem in commercial broiler farming. Free-range chicken producers need to identify chicken gender to estimate the economic value of their flock. However, it is challenging for farmers to estimate the gender ratio of chickens efficiently and accurately, since the environmental background is complicated and the chicken number is dynamic. Moreover, manual estimation is likely double counts or missed count and thus is inaccurate and time consuming. Hence, automated methods that can lead to results efficiently and accurately replace the identification abilities of a chicken gender expert, working in a farm environment, are beneficial to the industry. The contributions in this paper include: (1) Building the world's first chicken gender classification database annotated manually, which comprises 800 chicken flock images captured on a farm and 1000 single chicken images separated from the flock images by an object detection network, labelled with gender information. (2) Training a rooster and hen classifier using a deep neural network and cross entropy in information theory to achieve an average accuracy of 96.85%. The evaluation of the algorithm performance indicates that the proposed automated method is practical for the gender classification of chickens on the farm environment and provides a feasible way of thinking for the estimation of the gender ratio.

14.
Opt Express ; 27(20): 29425-29438, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31684677

RESUMO

Long-term mutual coherence is a key factor that affects the signal-to-noise ratio and resolution of a dual-comb interferometer. To realize a phase-stable dual-comb interferometer configuration, tightly phase-locked loop systems or digital error correction methods with external optical reference are commonly used. This paper presents a self-referencing digital error correction method based on the short-term spectral characteristics of interferograms to reduce the cost and complexity of the phase-stable dual-comb interferometer configuration. In our experiment, fully mutual coherence of a dual-comb interferometer is reconstructed and 1 Hz theoretical linewidth in 1 s acquisition time is achieved by digitally compensating for time jitter, center frequency jitter, and carrier-envelope-phase jitter, offering an effective technique for advanced dual-comb applications.

15.
Chemistry ; 25(41): 9678-9690, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31087575

RESUMO

New N-heterocyclic olefins (NHOs) are described with functionalization on the ligand heterocyclic backbone and terminal alkylidene positions. Various PdII -NHO complexes have been formed and their use as pre-catalysts in Buchwald-Hartwig aminations was explored. The most active system for catalytic C-N bond formation between hindered arylamine and arylhalide substrates was accessed by combining a backbone methylated NHO with [Pd(cinnamyl)Cl]2 in the presence of NaOtBu as a base. In these active systems evidence suggests that catalysis is mediated by colloidal palladium metal, highlighting a different coordination ability of NHOs in comparison with commonly used N-heterocyclic carbene co-ligands.

16.
BMC Vet Res ; 15(1): 79, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30841883

RESUMO

BACKGROUND: Porcine circovirus type 3 (PCV3), recently widely isolated from pigs with various clinical conditions, is likely globally epidemic. However, development of serological diagnosis for PCV3 in pigs is ongoing. Our objectives were to: 1) establish an indirect ELISA, using PCV3 capsid protein (Cap) prepared by Baculovirus Expression Vector System (BEVS) as a high-quality coating antigen for detection of PCV3-associated antibodies in serum samples; and 2) use this ELISA to conduct a serological survey for PCV3 in various regions of Hunan province, China. RESULTS: The PCV3 positive rate to the ELISA assay (total of 190 serum samples) was higher in sows with reproductive failure compared to healthy sows (34/85, 40.0% versus 30/105, 28.6%), with similar results using qPCR assays. Further, in an additional 1038 serum samples collected from January 2016 to May 2018 in various regions of Hunan province and tested with this established ELISA, 20 to 84% were positive for PCV3 (according to region of sera collection), with high PCV3 seroprevalence (> 50%) in herds in Changde, Hengyang and Yueyang. Moreover, among serum samples from herds in Shaoyang and Changde, PCV3 seroprevalence was higher in sows than in other classes of pigs (i.e., suckling piglets, nursery pigs, gilts, growing-finishing pigs and boars). CONCLUSIONS: We developed a full-length PCV3 Cap-based ELISA using a eukaryotic expression system with excellent potential to elucidate PCV3 epidemiology. Based on this assay, PCV3 has been circulating in Hunan province. PCV3 prevalence was lower in healthy sows than in those with reproductive failure. Further studies are warranted to identify the PCV3 responsible for high seroprevalence in sows and determine pathogenesis of PCV3 in sows with reproductive failure.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/isolamento & purificação , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças dos Suínos/virologia , Animais , Baculoviridae , Proteínas do Capsídeo , China/epidemiologia , Infecções por Circoviridae/diagnóstico , Infecções por Circoviridae/epidemiologia , Circovirus/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Genitália Feminina/patologia , Genitália Feminina/virologia , Imunoglobulina G/imunologia , Masculino , Estudos Soroepidemiológicos , Suínos/sangue , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/epidemiologia
18.
Sensors (Basel) ; 19(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974747

RESUMO

A problem of tracking surface shape-shifting extended target by using gray scale pixels on optical image is considered. The measurement with amplitude information (AI) is available to the proposed method. The target is regarded as a convex hemispheric object, and the amplitude distribution of the extended target is represented by a solid radial function. The Gaussian process (GP) is applied and the covariance function of GP is modified to fit the convex hemispheric shape. The points to be estimated on the target surface are selected reasonably in the hemispheric space at the azimuth and pitch directions. Analytical representation of the estimated target extent is provided and the recursive process is implemented by the extended Kalman filter (EKF). In order to demonstrate the algorithm's ability of tracking complex shaped targets, a trailing target characterized by two feature parameters is simulated and the two feature parameters are extracted with the estimated points. The simulations verify the validity of the proposed method with compared to classical algorithms.

19.
Sensors (Basel) ; 18(6)2018 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-29795020

RESUMO

Spectral-spatial classification has been widely applied for remote sensing applications, especially for hyperspectral imagery. Traditional methods mainly focus on local spatial similarity and neglect nonlocal spatial similarity. Recently, nonlocal self-similarity (NLSS) has gradually gained support since it can be used to support spatial coherence tasks. However, these methods are biased towards the direct use of spatial information as a whole, while discriminative spectral information is not well exploited. In this paper, we propose a novel method to couple both nonlocal spatial and local spectral similarity together in a single framework. In particular, the proposed approach exploits nonlocal spatial similarities by searching non-overlapped patches, whereas spectral similarity is analyzed locally within the locally discovered patches. By fusion of nonlocal and local information, we then apply group sparse representation (GSR) for classification based on a group structured prior. Experimental results on three real hyperspectral data sets demonstrate the efficiency of the proposed approach, and the improvements are significant over the methods that consider either nonlocal or local similarity.

20.
Angew Chem Int Ed Engl ; 57(45): 14841-14846, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30239084

RESUMO

The synthesis of the first bismuth-containing macromolecules that exhibit phosphorescence in the solid state and in the presence of oxygen is reported. These red emissive high molecular weight polymers (>300 kDa) feature benzobismoles appended to a hydrocarbon scaffold, and were built via an efficient ring-opening metathesis (ROMP) protocol. Moreover, our general procedure readily allows for the formation of cross-linked networks and block copolymers. Attaining stable red phosphorescence with non-toxic elements remains a challenge and, thus, our new class of soluble (processable) polymeric phosphor is of great interest. Furthermore, the formation of bismuth-rich cores within organic-inorganic block copolymer spherical micelles is possible, leading to patterned arrays of bismuth in the film state.

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