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1.
Opt Express ; 32(3): 2942-2958, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297530

RESUMO

A method for spectral reflectance factor reconstruction based on wideband multi-illuminant imaging was proposed, using a programmable LED lighting system and modified Bare Bones Particle Swarm Optimization algorithms. From a set of 16 LEDs with different spectral power distributions, nine light sources with correlated color temperatures in the range of 1924 K - 15746 K, most of them daylight simulators, were generated. Samples from three color charts (X-Rite ColorChecker Digital SG, SCOCIE ScoColor paint chart, and SCOCIE ScoColor textile chart), were captured by a color industrial camera under the nine light sources, and used in sequence as training and/or testing colors. The spectral reconstruction models achieved under multi-illuminant imaging were trained and tested using the canonical Bare Bones Particle Swarm Optimization and its proposed modifications, along with six additional and commonly used algorithms. The impacts of different illuminants, illuminant combinations, algorithms, and training colors on reconstruction accuracy were studied comprehensively. The results indicated that training colors covering larger regions of color space give more accurate reconstructions of spectral reflectance factors, and combinations of two illuminants with a large difference of correlated color temperature achieve more than twice the accuracy of that under a single illuminant. Specifically, the average reconstruction error by the method proposed in this paper for patches from two color charts under A + D90 light sources was 0.94 and 1.08 CIEDE2000 color difference units. The results of the experiment also confirmed that some reconstruction algorithms are unsuitable for predicting spectral reflectance factors from multi-illuminant images due to the complexity of optimization problems and insufficient accuracy. The proposed reconstruction method has many advantages, such as being simple in operation, with no requirement of prior knowledge, and easy to implement in non-contact color measurement and color reproduction devices.

2.
J Nanobiotechnology ; 20(1): 279, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35701788

RESUMO

Cancer is a leading public health problem worldwide. Its treatment remains a daunting challenge, although significant progress has been made in existing treatments in recent years. A large concern is the poor therapeutic effect due to lack of specificity and low bioavailability. Gene therapy has recently emerged as a powerful tool for cancer therapy. However, delivery methods limit its therapeutic effects. Exosomes, a subset of extracellular vesicles secreted by most cells, have the characteristics of good biocompatibility, low toxicity and immunogenicity, and great designability. In the past decades, as therapeutic carriers and diagnostic markers, they have caught extensive attention. This review introduced the characteristics of exosomes, and focused on their applications as delivery carriers in DNA, messenger RNA (mRNA), microRNA (miRNA), small interfering RNA (siRNA), circular RNA (circRNA) and other nucleic acids. Meanwhile, their application in cancer therapy and exosome-based clinical trials were presented and discussed. Through systematic summarization and analysis, the recent advances and current challenges of exosome-mediated nucleic acid delivery for cancer therapy are introduced, which will provide a theoretical basis for the development of nucleic acid drugs.


Assuntos
Exossomos , Neoplasias , Ácidos Nucleicos , Sistemas de Liberação de Medicamentos/métodos , Humanos , Neoplasias/tratamento farmacológico , RNA Interferente Pequeno
3.
Nanotechnology ; 32(1): 015502, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32916663

RESUMO

In this work, we used graphene oxide (GO) as a template that was removed by calcination to finally successfully prepare Co3O4 with 2D porous nanostructure. The results show that 2D porous structure Co3O4 nanosheets were only prepared at pH = 2. After electrochemical tests, the as-prepared Co3O4 nanosheets showed electrochemical properties that are highly suitable for H2O2 detection, such as high current response, short response time (less than 3 s), wide linear range (0.388-44.156 mM), low limit of detection (2.33 µM) and high sensitivity (0.0891 mA mM-1 cm-2). These excellent properties are mainly due to GO, as a 2D template, which connects Co3O4 nanoparticles to each other on a 2D plane, preventing the agglomeration of Co3O4 nanoparticles. The abundant pores between Co3O4 nanoparticles can greatly increase the reaction between the nanoparticles and H2O2 molecules.

4.
Appl Opt ; 58(10): 2635-2640, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31045068

RESUMO

We demonstrate free-space transmission based on a broadband fiber laser at 16 Gbit/s over a simulated atmospheric turbulence channel. The broadband laser pulse is part of a supercontinuum generated by a homemade picosecond laser based on Raman gain soliton compression pumping a segment of highly nonlinear fiber. The scintillation indices, eye patterns, and bit error rates of transmission based on the broadband laser and a narrow-linewidth laser are compared. The results show a 29.5% reduction in the scintillation index and sensitivity of -28.6 dBm at the forward error correction limit, which has a 2.9 dB improvement compared with the narrow-linewidth system. It is feasible to use broadband lasers as carriers combining optical time division multiplexing as a multiplexing method to improve the communication performance under weak atmospheric turbulent conditions.

5.
Opt Express ; 26(18): 23819-23830, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30184878

RESUMO

We characterize the performance of the optical signal propagation model of multi-level pulse amplitude modulation (M-PAM) based on avalanche photodiode (APD) detector in the free-space link for the first time. When the number of photons absorbed by the active surface of the APD is large enough, the bit error rate (BER) performance relationship of the systems based on the signal intensity and the photon characteristics are depicted. We use the Gamma-Gamma (G-G) channel model to analysis the communication systems with joint parameter constraints, and demonstrate the atmospheric turbulence intensity, link lengths, optical wavelength, symbol transmission rate, temperature of APD and pointing errors (PEs) impact on the system average bit error rate (ABER) performance. Moreover, the relationship between signal-to-noise-ratio (SNR) and ABER rate is given. The numerical results show that the 4-PAM free-space optical (FSO) communication is suitable for medium-to-weak turbulence, and the high gain of APD can mitigate the influence of ABER. The best detection condition of the 4-PAM optical signal is at least 20 dB SNR, when the ABER is under the 7% forward error correction (FEC) limit of 3.8 × 10-3. This work provides a reference for parameter designing and evaluating in M-PAM FSO communication systems.

6.
Opt Lett ; 43(14): 3421-3424, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30004520

RESUMO

We report on a communication link demonstration in a 1 km simulated atmospheric turbulent channel with a wide-spectral mode-locking fiber laser. Wide-spectral beams are part of the supercontinuum, which is generated from pumping a dispersion-shifted fiber by an active mode-locked fiber laser. In addition, the propagation effects of wide-spectral beams were investigated experimentally in a simulated atmosphere channel. The characteristics of bit error rate and eye pattern before and after turbulence were analyzed, respectively. The experimental results showed that the sensitivity of the whole link reaches -40 dBm. The scintillation index of free-space optical communication between wide-spectral partially coherent and narrow-spectral coherent beams was compared, which indicates that the wide-spectral partially coherent optical communication link is more resistant to atmospheric turbulence. We experimentally verified that the scintillation index of wide-spectral carriers is dependent on coherent degree rather than spectral width.

7.
Nanoscale ; 16(16): 8162-8176, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38572710

RESUMO

The slow redox rate of hydrogen peroxide (H2O2) in neutral environments makes the H2O2 sensor inadequate for the detection of low levels of signalling molecules. The aim of this study is to fabricate a flexible sensing electrode by hydrothermally loading micro-nanometer Ni and Co(OH)2 on carbon cloth (CC) and electrochemically depositing poly(3,4-ethylenedioxythiophene) (PEDOT) on the surface of the electrode. The sensor presented high sensitivity (10.43 mA mM-1 cm-2), a wide detection range (0.033-120.848 mM), a low detection limit (0.92 nM), high stability, and excellent anti-interference performance in neutral solutions. Ni-Co(OH)2 provides abundant active sites while CC solves their agglomeration phenomenon and conductivity. The PEDOT film offers heightened conductivity, hydrophilicity, interfacial stability, and an electrochemically active surface area (ECSA). The side area of the chrysanthemum petal like PEDOT is 39 ± 7 times the bottom area, and PEDOT increases the ECSA of the composite to six times that of CC. Electrochemical precise control of PEDOT morphology to improve sensor performance provides a new strategy for the application of PEDOT in sensors.

8.
Biosensors (Basel) ; 14(2)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38392025

RESUMO

Precise DNA quantification and nuclear imaging are pivotal for clinical testing, pathological diagnosis, and drug development. The detection and localization of mitochondrial DNA serve as crucial indicators of cellular health. We introduce a novel conjugated oligoelectrolyte (COE) molecule, COE-S3, featuring a planar backbone composed of three benzene rings and terminal side chains. This unique amphiphilic structure endows COE-S3 with exceptional water solubility, a high quantum yield of 0.79, and a significant fluorescence Stokes shift (λex = 366 nm, λem = 476 nm), alongside a specific fluorescence response to DNA. The fluorescence intensity correlates proportionally with DNA concentration. COE-S3 interacts with double-stranded DNA (dsDNA) through an intercalation binding mode, exhibiting a binding constant (K) of 1.32 × 106 M-1. Its amphiphilic nature and strong DNA affinity facilitate its localization within mitochondria in living cells and nuclei in apoptotic cells. Remarkably, within 30 min of COE-S3 staining, cell vitality can be discerned through real-time nuclear fluorescence imaging of apoptotic cells. COE-S3's high DNA selectivity enables quantitative intracellular DNA analysis, providing insights into cell proliferation, differentiation, and growth. Our findings underscore COE-S3, with its strategically designed, shortened planar backbone, as a promising intercalative probe for DNA quantification and nuclear imaging.


Assuntos
DNA , Eletrólitos , Eletrólitos/química , Imagem Óptica/métodos , Mitocôndrias
9.
Macromol Biosci ; 24(4): e2300362, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38150293

RESUMO

RNA interference (RNAi) technology has been a promising treatment strategy for combating intractable diseases. However, the applications of RNAi in clinical are hampered by extracellular and intracellular barriers. To overcome these barriers, various siRNA delivery systems have been developed in the past two decades. The first approved RNAi therapeutic, Patisiran (ONPATTRO) using lipids as the carrier, for the treatment of amyloidosis is one of the most important milestones. This has greatly encouraged researchers to work on creating new functional siRNA carriers. In this review, the recent advances in siRNA carriers consisting of lipids, polymers, and polymer-modified inorganic particles for cancer therapy are summarized. Representative examples are presented to show the structural design of the carriers in order to overcome the delivery hurdles associated with RNAi therapies. Finally, the existing challenges and future perspective for developing RNAi as a clinical modality will be discussed and proposed. It is believed that the addressed contributions in this review will promote the development of siRNA delivery systems for future clinical applications.


Assuntos
Portadores de Fármacos , Nanopartículas , RNA Interferente Pequeno/química , Interferência de RNA , Portadores de Fármacos/química , Terapia Genética , Polímeros/química , Lipídeos/química , Nanopartículas/química
10.
Front Bioeng Biotechnol ; 12: 1352098, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38585708

RESUMO

The Chinese hamster ovarian (CHO) cells serve as a common choice in biopharmaceutical production, traditionally cultivated in stirred tank bioreactors (STRs). Nevertheless, the pursuit of improved protein quality and production output for commercial purposes demand exploration into new bioreactor types. In this context, inverted frustoconical shaking bioreactors (IFSB) present unique physical properties distinct from STRs. This study aims to compare the production processes of an antibody-based biotherapeutic in both bioreactor types, to enhance production flexibility. The findings indicate that, when compared to STRs, IFSB demonstrates the capability to produce an antibody-based biotherapeutic with either comparable or enhanced bioprocess performance and product quality. IFSB reduces shear damage to cells, enhances viable cell density (VCD), and improves cell state at a 5-L scale. Consequently, this leads to increased protein expression (3.70 g/L vs 2.56 g/L) and improved protein quality, as evidenced by a reduction in acidic variants from 27.0% to 21.5%. Scaling up the culture utilizing the Froude constant and superficial gas velocity ensures stable operation, effective mixing, and gas transfer. The IFSB maintains a high VCD and cell viability at both 50-L and 500-L scales. Product expression levels range from 3.0 to 3.6 g/L, accompanied by an improved acidic variants attribute of 20.6%-22.7%. The IFSB exhibits superior productivity and product quality, underscoring its potential for incorporation into the manufacturing process for antibody-based biotherapeutics. These results establish the foundation for IFSB to become a viable option in producing antibody-based biotherapeutics for clinical and manufacturing applications.

11.
J Endocr Soc ; 8(5): bvae027, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38487212

RESUMO

Context: Metabolic surgery remains the most effective and durable treatment for severe obesity and related metabolic diseases. Objective: We examined cardiometabolic improvements after metabolic surgery and associated presurgery demographic and clinical factors in a large multiracial cohort. Methods: Included were 7804 patients (20-79 years) undergoing first-time metabolic surgery at Vanderbilt University Medical Center from 1999 to 2022. Pre- and 1-year postsurgery cardiometabolic profiles were extracted from medical records, including body mass index (BMI), blood pressure, blood lipids, glucose, and hemoglobin A1c. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk was estimated per American College of Cardiology/American Heart Association equations. Pre- to postsurgery cardiometabolic profiles were compared by paired t-test, and associated factors were identified by multivariable linear and logistic regression. Results: Among 7804 patients, most were women and White, while 1618 were men and 1271 were Black; median age and BMI were 45 years [interquartile range (IQR): 37-53] and 46.4 kg/m2 (IQR: 42.1-52.4). At 1-year postsurgery, patients showed significant decreases in systolic blood pressure (10.5 [95% confidence interval: 10.1, 10.9] mmHg), total cholesterol (13.5 [10.3, 16.7] mg/dL), glucose (13.6 [12.9, 14.4] mg/dL), hemoglobin A1c (1.13% [1.06, 1.20]), and 10-year ASCVD risk (absolute reduction: 1.58% [1.22, 1.94]; relative reduction: 34.4% [29.4, 39.3]); all P < .0001. Older, male, or Black patients showed less reduction in 10-year ASCVD risk and lower odds of diabetes/hypertension/dyslipidemia remission than younger, female, or White patients. Patients with a history of diabetes, hypertension, dyslipidemia, or cardiovascular disease showed less cardiometabolic improvements than those without. Results were similar with or without further adjusting for weight loss and largely sustained at 2-year postsurgery. Conclusion: Metabolic surgery results in significant cardiometabolic improvements, particularly among younger, female, or White patients and those without comorbidities.

12.
medRxiv ; 2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38293039

RESUMO

Background: Bariatric surgery is an effective intervention for obesity, but it requires comprehensive postoperative self-management to achieve optimal outcomes. While patient portals are generally seen as beneficial in engaging patients in health management, the link between their use and post-bariatric surgery weight loss remains unclear. Objective: This study investigated the association between patient portal engagement and postoperative body mass index (BMI) reduction among bariatric surgery patients. Methods: This retrospective longitudinal study included patients who underwent Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) at Vanderbilt University Medical Center (VUMC) between January 2018 and March 2021. Using generalized estimating equations, we estimated the association between active days of postoperative patient portal use and the reduction of BMI percentage (%BMI) at 3, 6, and 12 months post-surgery. Covariates included duration since surgery, the patient's age at the time of surgery, gender, race and ethnicity, type of bariatric surgery, severity of comorbid conditions, and socioeconomic disadvantage. Results: The study included 1,415 patients, mostly female (80.9%), with diverse racial and ethnic backgrounds. 805 (56.9%) patients underwent RYGB and 610 (43.1%) underwent SG. By one-year post-surgery, the mean (SD) %BMI reduction was 31.1% (8.3%), and the mean (SD) number of patient portal active days was 61.0 (41.2). A significantly positive association was observed between patient portal engagement and %BMI reduction, with variations revealed over time. Each 10-day increment of active portal use was associated with a 0.57% ([95% CI: 0.42- 0.72], P < .001) and 0.35% ([95% CI: 0.22- 0.49], P < .001) %BMI reduction at 3 and 6 months postoperatively. The association was not statistically significant at 12 months postoperatively (ß=-0.07, [95% CI: -0.24- 0.09], P = .54). Various portal functions, including messaging, visits, my record, medical tools, billing, resources, and others, were positively associated with %BMI reduction at 3- and 6-months follow-ups. Conclusions: Greater patient portal engagement, which may represent stronger adherence to postoperative instructions, better self-management of health, and enhanced communication with care teams, was associated with improved postoperative weight loss. Future investigations are needed to identify important portal features that contribute to the long-term success of weight loss management.

13.
Materials (Basel) ; 16(22)2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-38005057

RESUMO

As a major load-bearing component of trains, the weld quality of the bogie beam is critical to the safety of railway operations. This study specifically investigates the inertia friction welding process of S355 bogie crosshead tubes, with the aim of improving the weld quality and achieving one-time formation of the crosshead tube and tube seat. The microstructural features and mechanical properties of S355 inertia-welded joints were also compared with the base metal. Research indicates that inertia friction welds have no visible defects, and that the microstructure of the welding seam (WS) consists of granular bainite, acicular ferrite and little pearlite. The thermo-mechanically affected zone (TMAZ) consists of granular bainite bands and ferrite + pearlite bands. The hot work strengthening mechanism of inertia friction welding results in a higher level of hardness for both WS and TMAZ. The tensile property of the welded joints can be compared to the base metal. The yield strength, tensile strength and elongation of the welded joints, respectively, reach 87.5%, 100% and 79.5% of S355. However, the impact toughness of the welds at room temperature is lower than that of the base material, particularly in the TMAZ zone. Conversely, in an environment with a temperature of -40 °C, WS's impact toughness surpasses that of the parent material.

14.
AMIA Annu Symp Proc ; 2023: 1047-1056, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38222326

RESUMO

Deep learning continues to rapidly evolve and is now demonstrating remarkable potential for numerous medical prediction tasks. However, realizing deep learning models that generalize across healthcare organizations is challenging. This is due, in part, to the inherent siloed nature of these organizations and patient privacy requirements. To address this problem, we illustrate how split learning can enable collaborative training of deep learning models across disparate and privately maintained health datasets, while keeping the original records and model parameters private. We introduce a new privacy-preserving distributed learning framework that offers a higher level of privacy compared to conventional federated learning. We use several biomedical imaging and electronic health record (EHR) datasets to show that deep learning models trained via split learning can achieve highly similar performance to their centralized and federated counterparts while greatly improving computational efficiency and reducing privacy risks.


Assuntos
Aprendizado Profundo , Informática Médica , Humanos , Registros Eletrônicos de Saúde , Privacidade
15.
JAMA Netw Open ; 6(10): e2336383, 2023 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-37812421

RESUMO

Importance: US health professionals devote a large amount of effort to engaging with patients' electronic health records (EHRs) to deliver care. It is unknown whether patients with different racial and ethnic backgrounds receive equal EHR engagement. Objective: To investigate whether there are differences in the level of health professionals' EHR engagement for hospitalized patients according to race or ethnicity during inpatient care. Design, Setting, and Participants: This cross-sectional study analyzed EHR access log data from 2 major medical institutions, Vanderbilt University Medical Center (VUMC) and Northwestern Medicine (NW Medicine), over a 3-year period from January 1, 2018, to December 31, 2020. The study included all adult patients (aged ≥18 years) who were discharged alive after hospitalization for at least 24 hours. The data were analyzed between August 15, 2022, and March 15, 2023. Exposures: The actions of health professionals in each patient's EHR were based on EHR access log data. Covariates included patients' demographic information, socioeconomic characteristics, and comorbidities. Main Outcomes and Measures: The primary outcome was the quantity of EHR engagement, as defined by the average number of EHR actions performed by health professionals within a patient's EHR per hour during the patient's hospital stay. Proportional odds logistic regression was applied based on outcome quartiles. Results: A total of 243 416 adult patients were included from VUMC (mean [SD] age, 51.7 [19.2] years; 54.9% female and 45.1% male; 14.8% Black, 4.9% Hispanic, 77.7% White, and 2.6% other races and ethnicities) and NW Medicine (mean [SD] age, 52.8 [20.6] years; 65.2% female and 34.8% male; 11.7% Black, 12.1% Hispanic, 69.2% White, and 7.0% other races and ethnicities). When combining Black, Hispanic, or other race and ethnicity patients into 1 group, these patients were significantly less likely to receive a higher amount of EHR engagement compared with White patients (adjusted odds ratios, 0.86 [95% CI, 0.83-0.88; P < .001] for VUMC and 0.90 [95% CI, 0.88-0.92; P < .001] for NW Medicine). However, a reduction in this difference was observed from 2018 to 2020. Conclusions and Relevance: In this cross-sectional study of inpatient EHR engagement, the findings highlight differences in how health professionals distribute their efforts to patients' EHRs, as well as a method to measure these differences. Further investigations are needed to determine whether and how EHR engagement differences are correlated with health care outcomes.


Assuntos
Registros Eletrônicos de Saúde , Etnicidade , Disparidades em Assistência à Saúde , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Negro ou Afro-Americano , Estudos Transversais , Registros Eletrônicos de Saúde/estatística & dados numéricos , Brancos , Hospitalização/estatística & dados numéricos , Atitude do Pessoal de Saúde , Idoso , Disparidades em Assistência à Saúde/etnologia , Disparidades em Assistência à Saúde/estatística & dados numéricos , Fatores de Tempo
16.
Adv Healthc Mater ; 12(3): e2201306, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36308025

RESUMO

Osteosarcoma often occurs in children and adolescents with high invasiveness and high mortality. Polo-like kinase 1 (PLK1) overexpressed in most tumors promotes cancer cell proliferation and transformation. PLK1 is considered as a therapeutic target for osteosarcoma. RNA interference-based therapies are employed to combat osteosarcoma through silencing PLK1 gene expression. However, the treatment results remain unsatisfactory due to the lack of a safe and efficient nonviral gene vector. To tackle this hurdle, biodegradable and CO2 -derivative cationic poly(vinylcyclohexene carbonates) (CPCHCs) are used as gene vectors to perform a siPLK1 therapeutic strategy for osteosarcoma treatment. Of those CPCHCs, CPCHC60 demonstrates the most excellent performance in gene transfection efficiency, endo-lysosome escaping, biodegradability, and biosafety. With the treatment of CPCHCs/siRNA nanoparticles, the expression level of PLK1 gene in osteosarcoma cells is significantly down-regulated. Subsequently, cells are arrested in the G2 /M phase and subsequently dead in the form of apoptosis, resulting in significant tumor regression both in vitro and in vivo. This study brings a new insight into the development of superior nonviral gene vectors for practical cancer treatment. Based on the results, the resulting nanoparticle-based gene drug formation is considered to have a highly successful chance in further translational nanomedicine applications.


Assuntos
Neoplasias Ósseas , Vetores Genéticos , Osteossarcoma , Humanos , Apoptose , Dióxido de Carbono , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Terapia Genética/métodos , RNA Interferente Pequeno/genética
17.
Dalton Trans ; 51(22): 8714-8722, 2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35611935

RESUMO

White light-emitting diodes (WLEDs) possess the advantages of environmental friendliness, long lifetime, and energy saving. Recently, metal-organic frameworks (MOFs) have become one of the hot candidates for LEDs. However, the tunable color and thermal stability of MOFs are urgent problems for their actual applications. In this work, Ln-MOFs (Ln = Eu, Tb) were synthesized by a facile wet chemical route. A series of Ln-MOFs phosphors with tunable luminescence color showed potential applications in white LEDs. The emission color of the phosphors can be easily modulated by changing the molar ratio of the raw materials. The luminescence intensities of Ln-MOFs retained over 90.6% of the initial value, showing excellent thermal stability of Ln-MOFs. In order to explore the potential applications of Ln-MOFs in WLEDs, we mixed them with two kinds of blue phosphors and packaged them to obtain WLEDs. The CIE coordinates of both were (0.31, 0.33) and (0.31, 0.34), which were able to achieve white light emission. The peak shape and peak position in the EL spectrum of the WLEDs device remained stable when increasing the applied current of the device. Meanwhile, the white light with excellent color quality and visual performance was achieved. The results show that Ln-MOFs are potential materials for white light LED, and provide a novel idea for the application of Ln-MOFs materials in the luminescence field.

18.
Front Plant Sci ; 13: 1008819, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36325573

RESUMO

In view of the problem that manual selection of hyperparameters may lead to low performance and large consumption of manpower cost of the convolutional neural network (CNN), this paper proposes a nonlinear convergence factor and weight cooperative self-mapping chaos optimization algorithm (WOACW) to optimize the hyperparameters in the identification and classification model of rice leaf disease images, such as learning rate, training batch size, convolution kernel size and convolution kernel number. Firstly, the opposition-based learning is added to the whale population initialization with improving the diversity of population initialization. Then the algorithm improves the convergence factor, increases the weight coefficient, and calculates the self-mapping chaos. It makes the algorithm have a strong ability to find optimization in the early stage of iteration and fast convergence rate. And disturbance is carried out to avoid falling into local optimal solution in the late stage of iteration. Next, a polynomial mutation operator is introduced to correct the current optimal solution with a small probability, so that a better solution can be obtained in each iteration, thereby enhancing the optimization performance of the multimodal objective function. Finally, eight optimized performance benchmark functions are selected to evaluate the performance of the algorithm, the experiment results show that the proposed WOACW outperforms than 5 other common improved whale optimization algorithms. The WOACW_SimpleNet is used to identify rice leaf diseases (rice blast, bacterial leaf blight, brown spot disease, sheath blight and tungro disease), and the experiment results show that the identification average recognition accuracy rate reaches 99.35%, and the F1-score reaches 99.36%.

19.
AMIA Annu Symp Proc ; 2022: 1247-1256, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37128421

RESUMO

Electronic health records (EHRs) usage and clinical workflows are intrinsically linked. To accommodate the complex care settings (e.g., emergency departments), EHR utilization workflows dynamically change in clinical practice, which in turn shapes the clinical workflows. Learning EHR workflows would provide an opportunity for healthcare organizations to enhance clinical workflows in the context of EHRs. However, very few studies investigated HER utilization workflows executed in clinical practice. We develop a network analysis framework and apply it to EHR audit logs to infer EHR workflows. We then measure the differences in the workflows between patient subgroups divided by races via differential network analysis. We apply our framework to trauma patients admitted to the emergency department, which is one of the clinical settings that need timely support from EHR utilizations. Our results show five core EHR workflows related to Narrator, Navigator, SmartTools, Chart Review, and ED workup activities in the ED. We find EHR workflows involving Narrator, SmartTools, and BPA are different when comparing patient subgroups.


Assuntos
Registros Eletrônicos de Saúde , Hospitalização , Humanos , Fluxo de Trabalho , Serviço Hospitalar de Emergência
20.
J Am Med Inform Assoc ; 29(9): 1584-1592, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35641135

RESUMO

OBJECTIVE: Deep learning models for clinical event forecasting (CEF) based on a patient's medical history have improved significantly over the past decade. However, their transition into practice has been limited, particularly for diseases with very low prevalence. In this paper, we introduce CEF-CL, a novel method based on contrastive learning to forecast in the face of a limited number of positive training instances. MATERIALS AND METHODS: CEF-CL consists of two primary components: (1) unsupervised contrastive learning for patient representation and (2) supervised transfer learning over the derived representation. We evaluate the new method along with state-of-the-art model architectures trained in a supervised manner with electronic health records data from Vanderbilt University Medical Center and the All of Us Research Program, covering 48 000 and 16 000 patients, respectively. We assess forecasting for over 100 diagnosis codes with respect to their area under the receiver operator characteristic curve (AUROC) and area under the precision-recall curve (AUPRC). We investigate the correlation between forecasting performance improvement and code prevalence via a Wald Test. RESULTS: CEF-CL achieved an average AUROC and AUPRC performance improvement over the state-of-the-art of 8.0%-9.3% and 11.7%-32.0%, respectively. The improvement in AUROC was negatively correlated with the number of positive training instances (P < .001). CONCLUSION: This investigation indicates that clinical event forecasting can be improved significantly through contrastive representation learning, especially when the number of positive training instances is small.


Assuntos
Saúde da População , Registros Eletrônicos de Saúde , Previsões , Humanos
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