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1.
Int J Nanomedicine ; 19: 4495-4513, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38799696

RESUMEN

Background: Electrical stimulation (ES) can effectively promote skin wound healing; however, single-electrode-based ES strategies are difficult to cover the entire wound area, and the effectiveness of ES is often limited by the inconsistent mechanical properties of the electrode and wound tissue. The above factors may lead to ES treatment is not ideal. Methods: A multifunctional conductive hydrogel dressing containing methacrylated gelatin (GelMA), Ti3C2 and collagen binding antimicrobial peptides (V-Os) was developed to improve wound management. Ti3C2 was selected as the electrode component due to its excellent electrical conductivity, the modified antimicrobial peptide V-Os could replace traditional antibiotics to suppress bacterial infections, and GelMA hydrogel was used due to its clinical applicability in wound healing. Results: The results showed that this new hydrogel dressing (GelMA@Ti3C2/V-Os) not only has excellent electrical conductivity and biocompatibility but also has a durable and efficient bactericidal effect. The modified antimicrobial peptides V-Os used were able to bind more closely to GelMA hydrogel to exert long-lasting antibacterial effects. The results of cell experiment showed that the GelMA@Ti3C2/V-Os hydrogel dressing could enhance the effect of current stimulation and significantly improve the migration, proliferation and tissue repair related genes expression of fibroblasts. In vitro experiments results showed that under ES, GelMA@Ti3C2/V-Os hydrogel dressing could promote re-epithelialization, enhance angiogenesis, mediate immune response and prevent wound infection. Conclusion: This multifunctional nanocomposite hydrogel could provide new strategies for promoting infectious wound healing.


Asunto(s)
Antibacterianos , Conductividad Eléctrica , Hidrogeles , Nanocompuestos , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Nanocompuestos/química , Animales , Hidrogeles/química , Hidrogeles/farmacología , Ratones , Estimulación Eléctrica , Gelatina/química , Humanos , Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Fibroblastos/efectos de los fármacos , Titanio/química , Titanio/farmacología , Masculino , Proliferación Celular/efectos de los fármacos , Terapia por Estimulación Eléctrica/métodos
2.
Sci Prog ; 107(1): 368504241238612, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500356

RESUMEN

In the production of air conditioners, there are various issues such as complex requirements, redundant stations, excessive man-hours, and low production line balance rate. This paper aims to address these problems by analyzing the historical data of H Company's commercial air conditioner production line. The data is categorized into five aspects: station, working hours, standard working hours, labor capacity, and presence of bottleneck processes. To optimize and improve the second production line, this paper applies the production line balance management method based on data mining. It utilizes the decision tree model in data mining and incorporates lean production knowledge from industrial engineering. The goal is to identify crucial factors that affect the balance of the production line and address the issues caused by these factors. The aim is to reduce and eliminate redundant working hours and enhance the balance rate of the production line. By implementing the approach outlined in this paper, the bottleneck time of the second production line was reduced from 96.67 s to 74.6 s, and the production line balance rate increased from 68% to 85%.

3.
Front Pediatr ; 11: 1172111, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664548

RESUMEN

Introduction: The emergence of the Omicron variant has seen changes in the clinical and radiological presentations of COVID-19 in pediatric patients. We sought to compare these features between patients infected in the early phase of the pandemic and those during the Omicron outbreak. Methods: A retrospective study was conducted on 68 pediatric COVID-19 patients, of which 31 were infected with the original SARS-CoV-2 strain (original group) and 37 with the Omicron variant (Omicron group). Clinical symptoms and chest CT scans were examined to assess clinical characteristics, and the extent and severity of lung involvement. Results: Pediatric COVID-19 patients predominantly had normal or mild chest CT findings. The Omicron group demonstrated a significantly reduced CT severity score than the original group. Ground-glass opacities were the prevalent radiological findings in both sets. The Omicron group presented with fewer symptoms, had milder clinical manifestations, and recovered faster than the original group. Discussion: The clinical and radiological characteristics of pediatric COVID-19 patients have evolved with the advent of the Omicron variant. For children displaying severe symptoms warranting CT examinations, it is crucial to weigh the implications of ionizing radiation and employ customized scanning protocols and protective measures. This research offers insights into the shifting disease spectrum, aiding in the effective diagnosis and treatment of pediatric COVID-19 patients.

4.
Math Biosci Eng ; 20(2): 3120-3145, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36899574

RESUMEN

When a cloud manufacturing environment extends to multi-user agent, multi-service agent and multi-regional spaces, the process of manufacturing services faces increased disturbances. When a task exception occurs because of disturbance, it is necessary to quickly reschedule the service task. We propose a multi-agent simulation modeling approach to simulate and evaluate the service process and task rescheduling strategy of cloud manufacturing, with which impact parameters can be achieved through careful study under different system disturbances. First, the simulation evaluation index is designed. In addition to the quality of service index of cloud manufacturing, the adaptive ability of task rescheduling strategy in response to a system disturbance is considered, and the flexibility of cloud manufacturing service index is proposed. Second, considering the substitution of resources, the internal and external transfer strategies of service providers are proposed. Finally, a simulation model of the cloud manufacturing service process of a complex electronic product is constructed by multi-agent simulation, and simulation experiments under multiple dynamic environments are designed to evaluate different task rescheduling strategies. The experimental results indicate that the external transfer strategy of the service provider in this case has higher quality of service and flexibility of service. Sensitivity analysis indicates that the matching rate of substitute resources for internal transfer strategy of service providers and the logistics distance of external transfer strategy of service providers are both sensitive parameters, which have significant impacts on the evaluation indexes.

5.
Front Psychiatry ; 13: 980371, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36159911

RESUMEN

Multiple system atrophy (MSA) is a common atypical parkinsonism, characterized by a varying combination of autonomic, cerebellar, and pyramidal systems. It has been noticed that the patients with MSA can be accompanied by some neuropsychiatric disorders, in particular depression. However, there is limited understanding of MSA-related depression. To bridge existing gaps, we summarized research progress on this topic and provided a new perspective regarding pathological, clinical, and imaging aspects. Firstly, we synthesized corresponding studies in order to investigate the relationship between depression and MSA from a pathological perspective. And then, from a clinical perspective, we focused on the prevalence of depression in MS patients and the comparison with other populations. Furthermore, the associations between depression and some clinical characteristics, such as life quality and gender, have been reported. The available neuroimaging studies were too sparse to draw conclusions about the radiological aspect of depression in MSA patients but we still described them in the presence of paper. Finally, we discussed some limitations and shortcomings existing in the included studies, which call for more high-quality basic research and clinical research in this field.

6.
Front Oncol ; 12: 957892, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35965573

RESUMEN

Background: This study aimed to analyze the pathological characteristics and predictive factors of prostate biopsy in men with PSA levels below 4.0 ng/ml. Patients and methods: We retrospectively analyzed 158 patients who underwent prostate biopsy with PSA levels below 4.0 ng/ml. Pathological results were statistically analyzed. The logistic regression analysis was used to determine the predictive factors for malignant outcomes. Subgroup analysis was performed on patients who received surgery and the postoperative pathological upgrading was counted. Results: A total of 143 patients were enrolled. The tumor detection rate was 20.3%. Among these patients, most of them (79.3%) had prostate adenocarcinoma, but rare malignant tumors also accounted for 20.7%. Logistic regression analysis indicated that the only independent predictive factor for a positive prostate biopsy was the PI-RADS score. For prostate adenocarcinoma cases, 95.7% of them were organ localized and 47.8% of cases were clinically significant. Subgroup analysis was performed on 14 patients who received surgical treatment. 28.6% of patients were upgraded to clinically significant prostate cancer, while 64.3% of patients had an upgrade in tumor stage. Conclusion: Our study indicated that 20.3% of men with PSA levels between 0 and 4.0 ng/ml were diagnosed with prostate malignancies. Among these patients, most of them (79.3%) were diagnosed with prostate adenocarcinoma, and several uncommon types of malignancies were also detected in 20.7% of patients. The only risk factor for a positive biopsy in patients with a low PSA concentration was the PI-RADS score. It should be emphasized that the invasiveness of PCa patients diagnosed by biopsy may be underestimated as more than half of patients will upgrade their Gleason score or clinical stages after surgery. Thus, clinicians should pay more attention to patients with PSA levels between 0 and 4.0 ng/ml.

7.
J Healthc Eng ; 2022: 2004973, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35432838

RESUMEN

Objective: To study the effect of apatinib combined with seggio on the expression of serum AFP and CA724 and the long-term survival rate in advanced gastric cancer patients undergoing comfort nursing intervention. Methods: 98 advanced gastric cancer patients were divided into single-drug group and joint group. Both groups of patients were given comfort nursing intervention, the single-drug group was treated with seggio, and the joint group was treated with apatinib and seggio. The clinical efficacy, survival rate, relationship between the tumor markers and the survival time, serum tumor markers levels (CA724 and AFP), inflammatory factors (IL-4, IL-10) levels, quality-of-life scores, and immunity function were measured after treatment. Results: The clinical efficacy in the joint group was better than that in the single-drug group. The three-year survival time in the joint group was upregulated relative to the single-drug group. The patients with high expression of CA724 or AFP had a lower survival time than the patients with low expression of CA724 or AFP. After treatment, IL-10 and IL-4 levels were obviously decreased, and the joint group showed a more obvious decrease compared with the single-drug group. The quality-of-life scores were significantly upregulated after treatment, and compared with the joint group, the scores in the single drug-group were obviously higher. The CD4+/CD8+, CD4+, and CD3+ levels were increased, while CD8+ levels were decreased after treatment, and the changes of each index in the joint group were more significant than those in the single-drug group. The content of CA724 and AFP were significantly decreased after treatment, and the joint group showed a more significant decrease than the single-drug group. Conclusion: Apatinib combined with seggio for advanced gastric cancer patients' treatment based on comfort nursing intervention can improve the clinical efficacy and survival time, reduce inflammatory factors and serum tumor markers levels, enhance patients' immune function, and quality of life.


Asunto(s)
Interleucina-10 , Neoplasias Gástricas , Biomarcadores de Tumor/uso terapéutico , Humanos , Interleucina-10/uso terapéutico , Interleucina-4/uso terapéutico , Piridinas , Calidad de Vida , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/patología , Tasa de Supervivencia , alfa-Fetoproteínas/uso terapéutico
9.
Front Oncol ; 11: 740868, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34589437

RESUMEN

PURPOSE: The purpose of this study is to explore the value of combining bpMRI and clinical indicators in the diagnosis of clinically significant prostate cancer (csPCa), and developing a prediction model and Nomogram to guide clinical decision-making. METHODS: We retrospectively analyzed 530 patients who underwent prostate biopsy due to elevated serum prostate specific antigen (PSA) levels and/or suspicious digital rectal examination (DRE). Enrolled patients were randomly assigned to the training group (n = 371, 70%) and validation group (n = 159, 30%). All patients underwent prostate bpMRI examination, and T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) sequences were collected before biopsy and were scored, which were respectively named T2WI score and DWI score according to Prostate Imaging Reporting and Data System version 2 (PI-RADS v.2) scoring protocol, and then PI-RADS scoring was performed. We defined a new bpMRI-based parameter named Total score (Total score = T2WI score + DWI score). PI-RADS score and Total score were separately included in the multivariate analysis of the training group to determine independent predictors for csPCa and establish prediction models. Then, prediction models and clinical indicators were compared by analyzing the area under the curve (AUC) and decision curves. A Nomogram for predicting csPCa was established using data from the training group. RESULTS: In the training group, 160 (43.1%) patients had prostate cancer (PCa), including 128 (34.5%) with csPCa. Multivariate regression analysis showed that the PI-RADS score, Total score, f/tPSA, and PSA density (PSAD) were independent predictors of csPCa. The prediction model that was defined by Total score, f/tPSA, and PSAD had the highest discriminatory power of csPCa (AUC = 0.931), and the diagnostic sensitivity and specificity were 85.1% and 87.5%, respectively. Decision curve analysis (DCA) showed that the prediction model achieved an optimal overall net benefit in both the training group and the validation group. In addition, the Nomogram predicted csPCa revealed good estimation when compared with clinical indicators. CONCLUSION: The prediction model and Nomogram based on bpMRI and clinical indicators exhibit a satisfactory predictive value and improved risk stratification for csPCa, which could be used for clinical biopsy decision-making.

10.
Front Mol Biosci ; 8: 648180, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34124146

RESUMEN

Purpose: By analyzing the CT manifestations and evolution of COVID in non-epidemic areas of southeast China, analyzing the developmental abnormalities and accompanying signs in the early and late stages of the disease, providing imaging evidence for clinical diagnosis and identification, and assisting in judging disease progression and monitoring prognosis. Methods: This retrospective and multicenter study included 1,648 chest CT examinations from 693 patients with laboratory-confirmed COVID-19 infection from 16 hospitals of southeast China between January 19 and March 27, 2020. Six trained radiologists analyzed and recorded the distribution and location of the lesions in the CT images of these patients. The accompanying signs include crazy-paving sign, bronchial wall thickening, microvascular thickening, bronchogram sign, fibrous lesions, halo and reverse-halo signs, nodules, atelectasis, and pleural effusion, and at the same time, they analyze the evolution of the abovementioned manifestations over time. Result: There were 1,500 positive findings in 1,648 CT examinations of 693 patients; the average age of the patients was 46 years, including 13 children; the proportion of women was 49%. Early CT manifestations are single or multiple nodular, patchy, or flaky ground-glass-like density shadows. The frequency of occurrence of ground-glass shadows (47.27%), fibrous lesions (42.60%), and microvascular thickening (40.60%) was significantly higher than that of other signs. Ground-glass shadows increase and expand 3-7 days after the onset of symptoms. The distribution and location of lesions were not significantly related to the appearance time. Ground-glass shadow is the most common lesion, with an average absorption time of 6.2 days, followed by consolidation, with an absorption time of about 6.3 days. It takes about 8 days for pure ground-glass lesions to absorb. Consolidation change into ground glass or pure ground glass takes 10-14 days. For ground-glass opacity to evolve into pure ground-glass lesions, it takes an average of 17 days. For ground-glass lesions to evolve into consolidation, it takes 7 days, pure ground-glass lesions need 8 days to evolve into ground-glass lesions. The average time for CT signs to improve is 10-15 days, and the first to improve is the crazy-paving sign and nodules; while the progression of the disease is 6-12 days, the earliest signs of progression are air bronchogram signs, bronchial wall thickening, and bronchiectasis. There is no severe patient in this study. Conclusion: This study depicts the CT manifestation and evolution of COVID in non-epidemic origin areas, and provides valuable first-hand information for clinical diagnosis and judgment of patient's disease evolution and prediction.

11.
Zhen Ci Yan Jiu ; 46(5): 416-20, 2021 May 25.
Artículo en Chino | MEDLINE | ID: mdl-34085466

RESUMEN

OBJECTIVE: To observe the curative effect of joint administration of acupuncture, western and herbal medicines and bamboo-jar-cupping in the treatment of locomotor dysfunction in patients with apoplexy (acute phase) of wind-phlegm blocking meridian-collateral type in acute stroke patients, and its influence on some relevant laboratory indexes. METHODS: A total of 100 cases of acute stroke patients of wind-phlegm blocking meridian-collateral type were recruited, and equally and randomly divided into control group and treatment group according to the random number table. The patients of both groups received treatment of conventional western medicines (for anti-platelet aggregation, blood-lipid regulation, arterial plaque-stabilization, cerebral cell protection and blood pressure-lowering), Chinese herbal medicines (for promoting blood circulation to dredge the meridian-collaterals), and acupuncture of Neiguan (PC6), Chize (LU5), Zusanli (ST36), Binao (LI14) and Sanyinjiao (SP6); and in addition, the patients of the treatment group also treated by cupping with bamboo-jar (kept for 10 min). The treatment was conducted once a day for 2 weeks. After the treatment, the National Institute of Health Stroke Scale (NIHSS), Fugl-Meyer assessment (FMA), Barthel Index (BI), and traditional Chinese medicine (TCM) syndrome score were used to assess the state of neurofunction, locomotor function, daily living ability, and TCM symptoms. The contents of serum C-reactive protein, D-dimer and blood homocysteine were detected using radical immunodiffusion, immunoturbidimetry, and enzymic methods, respectively. RESULTS: After the treatment, of the 50 and 50 cases in the control and treatment groups, 5 and 6 were cured, 7 and 18 experienced marked improvement, 23 and 20 were effective, and 15 and 6 ineffective, with the effective rate being significantly higher in the treatment group (88.0%) than in the control group (70.0%, P<0.05). Self-comparison showed that the FMA and BI scores were significantly increased (P<0.01), and the NIHSS score and TCM syndrome score notably decreased in both groups ( P<0.01) in comparison with their own pre-treatment. Comparison between the two groups showed that the FMA and BI scores were obviously higher in the treatment group than in the control group (P<0.05), whereas the NIHSS score and TCM syndrome score as well as the C-reaction protein content evidently lower in the treatment group than in the control group (P<0.05, P<0.01). CONCLUSION: Joint administration of acupuncture, western and Chinese herbal medicines and cupping can promote the recovery of nerve function, improve locomotor function, activities of daily living and quality of life, and reduce inflammatory state in acute stroke patients with wind-phlegm blocking collaterals.


Asunto(s)
Terapia por Acupuntura , Accidente Cerebrovascular , Actividades Cotidianas , Humanos , Calidad de Vida , Accidente Cerebrovascular/terapia , Resultado del Tratamiento , Viento
12.
Math Biosci Eng ; 18(1): 933-949, 2021 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-33525126

RESUMEN

In order to analyze the influence of the personnel flexibility on the flexibility of the production system and optimize the organization and configuration of the production system, this paper puts forward a flexible simulation study of production system personnel based on mixed modeling. Firstly, the flexible evaluation index of production system is constructed from four dimensions: machine utilization ratio, personnel utilization ratio, production and personnel production efficiency. The concrete calculation method is given accordingly. Secondly, the simulation model of discrete event-multibody mixed modeling in production system is established, and the construction principle of the model is given. Thirdly, based on the flexible evaluation index and mixed modeling method, the flexible personnel skills of a motorcycle engine key parts production system are simulated and analyzed, and the comparative analysis of multiple schemes is realized. The simulation results show that multi-energy and personnel cooperation have an important influence on the flexibility of production system. In the medium and large fluctuation production environment, compared with the professional production team, the flexibility of the four dimensions of machine utilization, personnel utilization, production and personnel production efficiency of the multi-energy production team has been significantly improved. The case study also shows that the hybrid modeling simulation model can realize the dynamic configuration and operation evaluation of the flexible personnel elements, and provide a dynamic and quantitative research method for the organizational optimization of the production system.

13.
Paediatr Child Health ; 26(1): e6-e10, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33542773

RESUMEN

PURPOSE: To characterize and compare children with correct diagnosis (CD) and misdiagnosis (MD) of tracheobronchial foreign body (TBFB). METHODS: A retrospective study was performed to review the medical records of children with CD group and MD group of TBFB. CD was defined when TBFB was identified during the first hospital visit. Otherwise, MD was considered. Demographic information, including gender, age, and clinical information, including clinical presentations and characteristics of foreign bodies, were retrieved. These characteristics were compared between two groups by Student's t-test or Wilcoxon two-sample test, or Chi-square analysis or Fisher's exact test, when appropriate. RESULTS: A total of 462 children with final diagnosis of TBFB were identified, with 276 children having CD and 186 children having MD. The most common location to identify the TBFB was right main bronchus in both CD and MD groups. Children with the previous history of respiratory tract foreign body were more likely to receive the CD. Children in MD group were more likely to have fever, as well as wheezing and crackles during physical examination. They were more likely to have pneumonia. Most common TBFB were peanuts. The majority of the TBFB were removed by the flexible bronchoscope coupled with forceps. CONCLUSION: Careful history taking and physical examination, especially for those children with unclear causes for their pneumonia or asthma, or children with no improvement on the treatments, should be performed to rule out the possibility of TBFB. Bronchoscopy should be performed if necessary.

14.
Trials ; 22(1): 85, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33482853

RESUMEN

BACKGROUND: Dyslipidemia is a major risk factor for atherosclerotic cardiovascular disease and a leading cause of death worldwide. The clinical utility of commonly used lipid-lowering drugs such as statins and fibrates is sometimes limited by the occurrence of various adverse reactions. Recently, berberine (BBR) has received increasing attention as a safer and more cost-effective option to manage dyslipidemia. Thus, a high-quality randomized controlled trial to evaluate the efficacy and safety of BBR in the treatment of dyslipidemia is deemed necessary. METHODS/DESIGN: This is a randomized, double-blind, and placebo-controlled clinical trial. A total of 118 patients with dyslipidemia will be enrolled in this study and randomized into two groups at a ratio of 1:1. BBR or placebo will be taken orally for 12 weeks. The primary outcome is the percentage of low-density lipoprotein cholesterol reduction at week 12. Other outcome measures include changes in other lipid profiles, high sensitivity C-reactive protein, blood pressure, body weight, Bristol Stool Chart, traditional Chinese medicine symptom form, adipokine profiles, and metagenomics of intestinal microbiota. Safety assessment includes general physical examination, blood and urine routine test, liver and kidney function test, and adverse events. DISCUSSION: This trial may provide high-quality evidence on the efficacy and safety of BBR for dyslipidemia. Importantly, the findings of this trial will help to identify patient and disease characteristics that may predict favorable outcomes of treatment with BBR and optimize its indication for clinical use. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900021361 . Registered on 17 February 2019.


Asunto(s)
Berberina , Medicamentos Herbarios Chinos , Dislipidemias , Berberina/efectos adversos , Manejo de Datos , Método Doble Ciego , Dislipidemias/diagnóstico , Dislipidemias/tratamiento farmacológico , Humanos , Medicina Tradicional China , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
15.
Ann Transl Med ; 8(15): 935, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32953735

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) has widely spread worldwide and caused a pandemic. Chest CT has been found to play an important role in the diagnosis and management of COVID-19. However, quantitatively assessing temporal changes of COVID-19 pneumonia over time using CT has still not been fully elucidated. The purpose of this study was to perform a longitudinal study to quantitatively assess temporal changes of COVID-19 pneumonia. METHODS: This retrospective and multi-center study included patients with laboratory-confirmed COVID-19 infection from 16 hospitals between January 19 and March 27, 2020. Mass was used as an approach to quantitatively measure dynamic changes of pulmonary involvement in patients with COVID-19. Artificial intelligence (AI) was employed as image segmentation and analysis tool for calculating the mass of pulmonary involvement. RESULTS: A total of 581 confirmed patients with 1,309 chest CT examinations were included in this study. The median age was 46 years (IQR, 35-55; range, 4-87 years), and 311 (53.5%) patients were male. The mass of pulmonary involvement peaked on day 10 after the onset of initial symptoms. Furthermore, the mass of pulmonary involvement of older patients (>45 years) was significantly severer (P<0.001) and peaked later (day 11 vs. day 8) than that of younger patients (≤45 years). In addition, there were no significant differences in the peak time (day 10 vs. day 10) and median mass (P=0.679) of pulmonary involvement between male and female. CONCLUSIONS: Pulmonary involvement peaked on day 10 after the onset of initial symptoms in patients with COVID-19. Further, pulmonary involvement of older patients was severer and peaked later than that of younger patients. These findings suggest that AI-based quantitative mass evaluation of COVID-19 pneumonia hold great potential for monitoring the disease progression.

16.
Ultrasonics ; 84: 180-186, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29154045

RESUMEN

In this study, cut-off frequencies of the circumferential SH waves in functionally graded piezoelectric-piezomagnetic material (FGPPM) cylinder shells with traction free, electrical and magnetic open boundary conditions are investigated analytically. The Wentzel-Kramers-Brillouin (WKB) method is employed for solving differential equations with variable coefficients for general cases. For comparison, Bessel functions and Kummer functions are used for solving cut-off frequency problems in homogenous and ideal FGPPM cylinder shells. It is shown that the WKB solution for the cut-off frequencies has good precise. The set of cut-off frequencies is a series of approximate arithmetic progressions, for which the difference is a function of the density and the effective elastic parameter. The relationship between the difference and the gradient coefficient is described. These results provide theoretical guidance for the non-destructive evaluation of curved shells based on the cut-off frequencies.

17.
ACS Appl Mater Interfaces ; 9(12): 10717-10729, 2017 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-28233993

RESUMEN

Porous carbon can be tailored to great effect for electrochemical energy storage. In this study, we propose a novel structured spherical carbon with a macrohollow core and a microporous shell derived from a sustainable biomass, amylose, by a multistep pyrolysis route without chemical etching. This hierarchically porous carbon shows a particle distribution of 2-10 µm and a surface area of 672 m2 g-1. The structure is an effective host of sulfur for lithium-sulfur battery cathodes, which reduces the dissolution of polysulfides in the electrolyte and offers high electrical conductivity during discharge/charge cycling. The hierarchically porous carbon can hold 48 wt % sulfur in its porous structure. The S@C hybrid shows an initial capacity of 1490 mAh g-1 and retains a capacity of 798 mAh g-1 after 200 cycles at a discharge/charge rate of 0.1 C. A capacity of 487 mAh g-1 is obtained at a rate of 3 C. Both a one-step pyrolysis and a chemical-reagent-assisted pyrolysis are also assessed to obtain porous carbon from amylose, but the obtained carbon shows structures inferior for sulfur cathodes. The multistep pyrolysis and the resulting hierarchically porous carbon offer an effective approach to the engineering of biomass for energy storage. The micrometer-sized spherical S@C hybrid with different sizes is also favorable for high-tap density and hence the volumetric density of the batteries, opening up a wide scope for practical applications.

18.
ISME J ; 11(1): 300-303, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27505346

RESUMEN

It is well known that bacteria often exist in naturally formed multispecies biofilms. Within these biofilms, interspecies interactions seem to have an important role in ecological processes. Little is known about the effects of interspecies interactions on gene expression in these multispecies biofilms. This study presents a comparative gene expression analysis of the Xanthomonas retroflexus transcriptome when grown in a single-species biofilm and in dual- and four-species consortia with Stenotrophomonas rhizophila, Microbacterium oxydans and Paenibacillus amylolyticus. The results revealed complex interdependent interaction patterns in the multispecies biofilms. Many of the regulated functions are related to interactions with the external environment and suggest a high phenotypic plasticity in response to coexistence with other species. Furthermore, the changed expression of genes involved in aromatic and branched-chain amino acid biosynthesis suggests nutrient cross feeding as a contributing factor for the observed synergistic biofilm production when these four species coexists in a biofilm.


Asunto(s)
Proteínas Bacterianas/genética , Biopelículas , Xanthomonas/fisiología , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Transcriptoma , Xanthomonas/clasificación , Xanthomonas/genética
19.
Acad Radiol ; 23(4): 438-45, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26872868

RESUMEN

RATIONALE AND OBJECTIVES: Using lower tube voltage can reduce the exposure to radiation and the dose of contrast agent. However, lower tube voltage is often linked to more noise and poor image quality, which create a need for more effective technology to resolve this problem. To explore the feasibility of coronary computed tomographic angiography (CCTA) in patients with obesity at low tube voltage (100 kV) and low contrast agent concentration (270 mg/mL) using iterative reconstruction. MATERIALS AND METHODS: A total of 48 patients with body mass index greater than 30 kg/m(2) were included and randomly divided into two groups. Group A received a traditional protocol (iopromide 370 mg/mL + 120 kV); group B received a protocol with low tube voltage (100 kV), low contrast agent concentration (270 mg/mL), and iterative reconstruction. The effective dose (ED), average attenuation values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), the figure of merit (FOM), image quality scores, and the total iodine intake were compared. RESULTS: No significant differences in average CT attenuations, SNR, CNR, and subjective scores were noticed between the two groups (P > 0.05), whereas the FOM of group B was significantly higher than that of group A. Effective radiation dose, total iodine, and iodine injection rate in group B were lower than those of group A (P <0.01). CONCLUSIONS: In patients with obesity, isotonic contrast agent with low iodine concentration and low-dose CCTA were feasible. Substantial reduction in radiation dose and the iodine intake could be achieved without compromising the image quality.


Asunto(s)
Medios de Contraste , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Obesidad/complicaciones , Dosis de Radiación , Intensificación de Imagen Radiográfica/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Enfermedad de la Arteria Coronaria/complicaciones , Estudios de Factibilidad , Femenino , Humanos , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Relación Señal-Ruido
20.
J Comput Assist Tomogr ; 40(2): 272-6, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26760190

RESUMEN

OBJECTIVE: The aim of the study was to investigate the feasibility of low-tube-voltage computed tomography (CT) in combination with 3-dimensional adaptive iterative dose reduction (AIDR-3D) algorithm in lower extremity CT angiography. METHODS: The CT data of the 120-kV group (n = 30) were reconstructed with filtered back projection (FBP) algorithm. The CT data of the 100-kV group (n = 30) were reconstructed with FBP as well as AIDR-3D algorithms. RESULTS: The 100-kV group showed significantly lower dose-length product than the 120-kV group (P < 0.05). In comparison with the 120-kV and FBP protocol, the 100-kV and FBP protocol showed significantly increased vascular density and noise (P < 0.05). However, in the 100-kV group, images reconstructed with AIDR-3D showed significantly lower noise and significantly higher signal-to-noise ratio and contrast-to-noise ratio than FBP (P < 0.05). CONCLUSIONS: Low-tube-voltage (100 kV) 320-row CT in combination with AIDR-3D reconstruction can significantly improve the image quality and reduce radiation dose of lower extremity CT angiography.


Asunto(s)
Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/diagnóstico por imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Algoritmos , Angiografía/métodos , Estudios de Factibilidad , Femenino , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Relación Señal-Ruido
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