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1.
PLoS One ; 18(11): e0294596, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38011124

RESUMO

The assessment of design concepts presents an efficient and effective strategy for businesses to strengthen their competitive edge and introduce market-worthy products. The widely accepted viewpoint acknowledges this as a intricate multi-criteria decision-making (MCDM) approach, involving a multitude of evaluative criteria and a significant amount of data that is frequently ambiguously defined and subjectively influenced. In order to tackle the problems of uncertainty and fuzziness in design concept evaluation, our research creatively combines interval-valued picture fuzzy set (IVPFS) with an MCDM process of design concept evaluation. Firstly, this study draws on the existing relevant literature and the experience of decision makers to identify some important criteria and corresponding sub-criteria and form a scientific evaluation indicator system. We then introduce the essential operational concepts of interval-valued picture fuzzy numbers (IVPFNs) and the interval-valued picture fuzzy ordered weighted interactive averaging (IVPFOWIA) operator. Thirdly, an entropy weighting method based on IVPFS is proposed in this research to calculate the weights of criteria and sub-criteria, and based on this, an integrated IVPF decision matrix is further constructed based on the presented IVPFOWIA operator. Finally, the best design concept alternative is selected by applying the extended TOPSIS (Technique for Order of Preference by Similarity to Ideal Solution) approach with IVPFS. The IVPFS combined with improved MCDM method have been proven to be superior in complex and uncertain decision-making situations through experiments and comparative assessments. The information ambiguity in the evaluation of design concept is well characterized by our augmentation based on IVPFS.


Assuntos
Tomada de Decisões , Lógica Fuzzy , Incerteza
2.
Medicine (Baltimore) ; 101(51): e32525, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36595817

RESUMO

RATIONALE: Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease which usually presents with painful, deep-seated, inflamed lesions in the apocrine gland-bearing areas. Severe HS has interconnecting sinus tracts and when it occurs in the perianal region, perianal fistulas can form. Obesity and smoking are 2 risk factors for the development of HS. PATIENT CONCERNS: We report a case of a 33-year-old male diagnosed with perianal HS and perianal fistula following a burn injury to the area that occurred during childhood. DIAGNOSIS: Through integration of the clinical signs and imaging results, the patient was diagnosed with HS, Hurley stage III with perianal fistulas. INTERVENTIONS: The patient accepted surgical therapy. Performed under the general anesthesia, the procedure comprised sinus tracts excision and drainage. OUTCOMES: The patient was discharged from the hospital 6 weeks after surgery. LESSONS: The pathogenesis of the HS in this case was the burn injury interfering with sweat gland formation around the anus. Moreover, the scar from the burn made surgical treatment difficult.


Assuntos
Fístula Cutânea , Hidradenite Supurativa , Fístula Retal , Masculino , Humanos , Adulto , Hidradenite Supurativa/complicações , Hidradenite Supurativa/cirurgia , Fístula Retal/complicações , Canal Anal , Pele , Fístula Cutânea/complicações
3.
Acupunct Herb Med ; 2(3): 207-209, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37808353

RESUMO

To explore on the association between nucleic acid turning-negative-time and traditional Chinese medicine (TCM) symptoms in coronavirus disease 2019 (COVID-19) patients with the Omicron variant. Method: For this retrospective cross-sectional study, we enrolled 189 patients with COVID-19 (age 20-90 years) were included. multiple linear regression models were used to investigate the TCM symptoms affecting the nucleic acid turning-negative-time of COVID-19 patients, during the process of data analysis, taking with nucleic acid turning-negative-time as the dependent variable, and TCM symptoms as independent variables, and at the same time, sex, age, hypertension, diabetes, and coronary heart disease were as confounding variables. Results: The study found that the most common TCM symptoms of COVID-19 patients with Omicron were cough, dry throat, expectoration, fever, sore throat, pharyngeal itching, running nose, and nasal congestion. Regression analysis showed that the fit regressive equation showed a significant difference (F = 4.286, P < 0.001), R = 0.400, the adjusted R 2 = 0.123, and three variables in the regression equation showed significant difference (P < 0. 05). The results showed that nucleic acid turning-negative-time was mostly related to constipation, fever, and expectoration. If the patients had the symptoms of constipation, fever, and expectoration; that is, if patients showed these symptoms, the turning-negative-time of nucleic acid in patients with Omicron will be prolonged. Conclusions: Treatment based on symptoms for patients with constipation, fever, and expectoration may have important clinical significance for the COVID-19 patients with Omicron.

4.
PLoS One ; 13(12): e0209011, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30562380

RESUMO

As a useful technology, the horizontal drilling for underground coalmine has been applied in many fields such as gas drainage, water control, exploration and accurate drilling borehole engineering. In this paper, the annulus tubes are used to simulate the fluid transportation process between drilling rod and casing tube when drilling horizontally. The main goal of this research is to analyze the effects of eccentricity, fluid velocity, outer tube length and volume fraction on dynamic characteristics of partially liquid-filled annulus tube in a drillstring system. According to the Euler-Bernoulli beam model, the partially liquid-filled inner tube model and outer tube model are established respectively when considering the effect of transport fluid inside the annulus tubes. Based on the vibration characteristics of the tube, the added mass coefficient is proposed to calculate the natural frequencies of the outer tubes. And natural frequency is the frequency at which a system tends to oscillate in the absence of any driving or damping force. According to the compared results of experiments and simulations, the natural characteristics of outer tube depend on the tube design parameter (outer tube length) and the volume fraction of liquid filled in the outer tube. Furthermore, experiments have verified that the natural frequencies of the outer tubes can be directly calculated from the length of outer tubes. Therefore, it is feasible to propose the method of attaching liquid mass to tube mass to obtain the natural frequencies of outer tubes. According to the results, it can be concluded that: (i) The natural frequencies of tube decrease as the length of the tube increases; (ii) The increase of volume fraction of liquid in the tube can significantly reduce the natural frequencies of tube; (iii) The fluid velocity and eccentricity have less effects on the natural frequencies of tube; (ⅳ) The added mass coefficient of outer tubes can be calculated and it is not a fixed value, it varies with the volume fraction of fluid in annulus tubes. In this work, the inner and outer tube models are established respectively for fluid transportation process between a horizontal drilling rod and casing tube. The effects of four factors on the natural frequencies are compared, and the concept of added mass coefficient is proposed to obtain reasonable tube natural frequencies.


Assuntos
Hidrodinâmica , Mineração/instrumentação , Modelos Teóricos , Algoritmos , Simulação por Computador , Vibração
5.
Carbohydr Res ; 345(5): 685-8, 2010 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20163791

RESUMO

The crystallographic study of a partially hydrated form of cyclomaltoheptaose (beta-cyclodextrin, betaCD) is reported. C(42)H(70)O(35).7.5H(2)O; space group P2(1) with unit cell constants a=15.1667(5), b=10.1850(3), c=20.9694(7)A, beta=110.993(2) degrees ; final discrepancy index R=0.0760 for the 6181 observed reflections and 784 refined parameters. One water molecule is included in the cavity and distributed over two partially occupied positions, the other 6.5 waters distributed over eight positions are located as space-filler between the macrocycles. The crystal structure belongs to the cage-type, like that observed in Form I (betaCD.12H(2)O; Lindner, K; Saenger, W. Carbohydr. Res. 1982, 99, 103-115) and Form II (betaCD.11H(2)O; Betzel, C., et al. J. Am. Chem. Soc., 1984, 106, 7545-7567).


Assuntos
Modelos Moleculares , Água/química , beta-Ciclodextrinas/química , Cristalização , Cristalografia por Raios X , Ligação de Hidrogênio , Difração de Raios X
6.
Carbohydr Res ; 345(1): 87-96, 2010 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-19926079

RESUMO

Redox-responsive vesicles self-assembled by supramolecular cyclodextrin amphiphiles, consisting of the guest (N-1-decyl-ferrocenylmethylamine, 1) and the host (2-O-carboxymethyl-beta-cyclodextrin, CM-beta-CD), were prepared. The morphologies and sizes of these novel vesicles in an aqueous solution were observed by transmission electron microscopy (TEM) and were confirmed by atomic force microscopy (AFM) and dynamic light scattering (DLS) measurements. The effects of the host-guest ratio, the concentration and the solvent composition of water and methanol on vesicles were investigated in detail. The interactions between the host and the guest, the complex stoichiometry, the stability constant and conformations of 1.CM-beta-CD in aqueous solution were investigated by cyclic voltammetry (CV), UV and nuclear magnetic resonance (NMR) measurements. According to the complex stoichiometry and 'tadpole-like' spatial conformations, the supramolecular cyclodextrin amphiphiles made from 1.CM-beta-CD were proposed to form the membranes of the vesicles. This kind of vesicle system was responsive to an oxidizing agent, which could pave the way to combine supramolecular host-guest chemistry and membrane chemistry for potentially functional applications.


Assuntos
Ciclodextrinas/química , Eletroquímica , Luz , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Conformação Molecular , Oxidantes/química , Oxirredução , Espalhamento de Radiação , Solubilidade , Água/química
7.
Carbohydr Res ; 343(15): 2517-22, 2008 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-18619585

RESUMO

6-Oligo(lactic acid)cyclomaltoheptaose (6-OLA-betaCD) with an average substitution of about 7.0 lactic acid units was prepared as a new water-soluble cyclomaltoheptaose (betaCD) derivative (solubility of about 70.7-fold that of betaCD), based on the ring-opening polymerization of 3,6-dimethyl-1,4-dioxane-2,5-dione (lactide). The product was characterized by (1)H NMR, (13)C NMR, IR, and MS spectroscopy. The complexation of amoxicillin with 6-OLA-betaCD was found to be much stronger than that with betaCD at first, and then 6-OLA-betaCD was shown to decompose moderately into betaCD and lactic acid. 6-OLA-betaCD might be greatly valuable in a controlled release system for Amoxicillin (AMX).


Assuntos
Amoxicilina/farmacocinética , Preparações de Ação Retardada , Ácido Láctico/química , beta-Ciclodextrinas/química , Amoxicilina/administração & dosagem , Química Farmacêutica/métodos , Relação Dose-Resposta a Droga , Hidrólise , Cinética , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Modelos Químicos , Solubilidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrofotometria Infravermelho/métodos , Raios Ultravioleta
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