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BACKGROUND:In recent years,additive manufacturing(also known as 3D printing)has gradually become the mainstream method for producing titanium alloy brackets for removable partial dentures.Heat treatment,as an important method to improve the mechanical properties of 3D printed titanium alloys,has become a current hot topic of attention.OBJECTIVE:To summarize the main heat treatment technologies currently applied to 3D printed titanium alloy specimens(including annealing,solution aging,hot isostatic pressing,and other heat treatments)and their effects on the mechanical properties and microstructure of 3D printed titanium alloy specimens,providing a theoretical basis for improving the heat treatment technology of removable partial denture titanium alloy supports.METHODS:A computer search was conducted on research materials related to 3D printed titanium alloy heat treatment in databases such as CNKI,PubMed,and ScienceDirect.The search period was from 2012 to 2023.A total of 61 articles were selected based on inclusion and exclusion criteria.RESULTS AND CONCLUSION:(1)Using conventional annealing techniques to treat 3D printed titanium alloy specimens,keeping them at 500-900 ℃ for 2-4 hours,can effectively increase the elongation of 3D printed titanium alloy specimens.(2)Compared to conventional annealing techniques,solid solution aging treatment is more complex,and the titanium alloy specimens after solid solution aging treatment exhibit outstanding yield strength and better corrosion resistance.However,the 3D printed titanium alloy specimens after solid solution aging treatment have no advantage in terms of ductility.(3)Hot isostatic pressing treatment can reduce the internal defects of 3D printed titanium alloy specimens,significantly increase the elongation of 3D printed titanium alloy specimens,and increase their fatigue life.(4)Rapid heat treatment can significantly improve the elongation of 3D printed titanium alloy specimens,and the speed is faster.In terms of elongation improvement and heat treatment efficiency,it has more advantages than conventional annealing in the past.(5)The improvement of elongation of 3D printed titanium alloy specimens by cyclic heat treatment exceeds that of conventional annealing.Cyclic heat treatment can significantly improve the grain structure of 3D printed titanium alloy specimens,but the heat treatment time is too long and the efficiency is low.
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Objective To propose a lung nodule diagnosis method based on CT image feature extraction and improved support vector machine(SVM)algorithm to enhance the accuracy and efficiency of automatic identification of lung nodules.Methods A cascade feature extraction method combining deep learning-based feature extraction and traditional manual extraction was used for CT image feature extraction,and the extracted features were input into an improved SVM algorithm to complete automated identification of lung nodules,using a multiple kernel learning support vector machine(MKL-SVM)algorithm and a particle swarm optimization(PSO)algorithm that integrated simulated annealing(SA)algorithm for parameter optimizing.The performance of cascade features was tested by comparing traditional feature extraction,deep learning-based feature extraction and cascade feature extraction.Comparison tests were performed using single kernel functions(RBF kernel,Sigmoid kernel and polynomial kernel functions)to validate the performance of the MKL-SVM algorithm.Tests were carried out using SVM functions with Sigmoid kernel to compare the fitness curves of the PSO algorithm and the PSO-SA algorithm for optimization to validate the effectiveness of the PSO-SA algorithm.Comparison analyses were conducted with the existing computer aided diagnosis(CAD)models of lung under the same dataset to verify the diagnostic efficacy of the proposed model of cascade features combined with improved MKL-SVM(cascade features with improved MKL-SVM,CF with MKL-SVM).Results The performance test results showed that cascade feature extraction had the F value with a mean value of 0.934 1,a maximum value of 0.957 3,a minimum value of 0.919 5 and a median value of 0.939 7,which behaved better in accuracy than manual feature extraction and deep learning-based feature extraction.The kernel function comparison test results indicated that the MKL-SVM algorithm had the best diagnostic performance with the mean value of F value of 0.924 3,the maximum value of 0.935 0 and the AUC value of 0.987 3.The Sigmoid kernel comparison test results found that PSO-SA al-gorithm had the best fitness value of 0.943 7,which gained advantages over the PSO algorithm.The model comparison test revealed that compared with the lung CAD model,the CF+MKL-SVM model had advantages in generalization ability,AUC value(0.9845),the values of all the indexes(all higher than 0.9),specificity and precision.Conclusion The proposed method can be used for automatic recognition of lung cancer and enhances the accuracy for detecting lung cancer.
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Abstract According to the Food and Agriculture Organization (FAO), roughly one-third of the total food produced is lost globally. The major cause of this wastage is the perishability of fruits and vegetables. Therefore, researchers have endeavored to develop an effective preservation technique. Our study explored the potential application of spider silk as an odourless and edible preservative coating for fruits. The spider silk was collected from spiders reared in the laboratory, following by degumming and dissolution to formulate the silk solution. For this study, apricots were selected as the model fruit. The apricots were dip coated with the formulated silk solution and allowed to dry. In order to enhance the beta sheet content of the silk coating, the fruits were exposed to water annealing for varying intervals of time under vacuum condition. The effect of silk coating and water annealing time period on preservation of fruits was then evaluated morphologically and gravimetrically. The results showed that the fruits, which were used as control, exhibited a greater degree of water loss and suffered from fungal attack. In contrast, the silk coated fruits showed less water loss and were protected from fungal attack. Therefore, the study provides compelling evidence regarding the application of spider silk as a preservative coating.
Resumo Segundo a Organização para Alimentação e Agricultura (FAO), cerca de um terço do total de alimentos produzidos é perdido globalmente. A principal causa deste desperdício é a perecibilidade das frutas e legumes. Portanto, os pesquisadores têm se esforçado para desenvolver uma técnica de preservação eficaz. Nosso estudo explorou a potencial aplicação de seda de aranha como um revestimento conservante inodoro e comestível para frutas. A seda da aranha foi coletada de aranhas criadas em laboratório, seguindo-se a degomagem e dissolução para formular a solução de seda. Para este estudo, os damascos foram selecionados como fruto modelo. Os damascos foram revestidos por imersão com a solução de seda formulada e deixados secar. A fim de aumentar o teor de folhas beta do revestimento de seda, os frutos foram expostos a recozimento de água durante vários intervalos de tempo sob condições de vácuo. O efeito do tempo de recobrimento de seda e recozimento de água na preservação de frutos foi então avaliado morfologicamente e gravimetricamente. Os resultados mostraram que os frutos, utilizados como controle, apresentaram maior grau de perda de água e sofreram ataque fúngico. Em contraste, os frutos revestidos de seda mostraram menos perda de água e foram protegidos contra ataques fúngicos. Portanto, o estudo fornece evidências convincentes sobre a aplicação de seda de aranha como um revestimento conservante.
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Spiders , Prunus armeniaca , Vegetables , Water , Silk , FruitABSTRACT
BACKGROUND: Previous studies have shown that titanium nanotubes with different diameters affect the adhesion and growth of cells on the implant surface. OBJECTIVE: To investigate the effects of annealing treatment on the biological behaviors of fibroblasts on the surface of TiO2 nanotubes with different diameters. METHODS: TiO2 nanotubes were prepared by polishing pure titanium samples through anodizing at 5 V and 20 V respectively, and then annealed. The pure titanium samples were divided into six groups: P (polishing titanium), NT5 (TiO2 nanotubes prepared at 5 V), NT20 (TiO2 nanotubes prepared at 20 V), A-P (annealing treatment and polishing titanium), A-NT5 (TiO2 nanotubes prepared at 5V and annealed) and A-NT20 (TiO2 nanotubes formed at 20 V and annealed). Field emission scanning electron microscopy was used to obsesrve the surface topography. Fibroblasts were inoculated on the surface of each group of samples. After 60 and 120 minutes of culture, the number of cells adhering to titanium sample surface was counted using cell nucleus staining method. On day 1 of culture, cell morphology was observed using scanning electron microscopy. On days 1, 3 and 5 of culture, cell proliferation was detected by MTT method. On day 3 of culture, the secretion of collagen fiber was detected by picro-sirius red staining method. RESULTS AND CONCLUSION: (1) The annealing treatment had no significant effect on the morphology and diameter of the nanotubes. (2) The number of adherent cells in the NT5 and NT20 groups was significantly lower than that in the P group. The annealing treatment increased the number of fibroblasts on the surface of polished pure titanium and decreased the number of fibroblasts in the NT5 and NT20 groups. (3) Annealing enhanced the viability of fibroblasts on the surface of polished pure titanium and decreased the viability of cells on the surface of nanotubes prepared at 5 and 20 V. (4) Cell viability in the NT5 and NT20 groups was lower than that in the P group. Annealing treatment increased the viability of cells on the surface of polished pure titanium and decreased the viability of cells on the surface of nanotubes prepared at 5 and 20 V. (5) The level of collagen on the surface of nanotubes in the NT5 and NT20 groups was higher than that in the P group. Annealing treatment increased the level of collagen on the surface of polished pure titanium and decreased the level of collagen in the NT5 and NT20 groups. These findings suggest that TiO2 nanotubes inhibit the adhesion, spreading and proliferation of fibroblasts to different degrees; annealing treatment can enhance this inhibitory effect; TiO2 nanotubes enhance collagen secretion by fibroblasts to different degrees, and annealing treatment inhibits the enhancement.
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OBJECTIVE@#To propose a probabilistic neural network classification method optimized by simulated annealing algorithm (SA-PNN) to discriminate lung cancer and adjacent normal tissues based on permittivity.@*METHODS@#The permittivity of lung tumors and the adjacent normal tissues was measured by an open-ended coaxial probe, and the statistical dependency (SD) algorithm was used for frequency screening.The permittivity associated with the selected frequency points was taken as the characteristic variable, and SA-PNN was used to discriminate lung cancer and the adjacent normal tissues.@*RESULTS@#Three frequency points, namely 984 MHz, 2724 MHz and 2723 MHz, were selected by SD algorithm.SA-PNN was used to discriminate 200 samples with the permittivity at the 3 frequency points as the characteristic variable.After 10-fold cross-validation, the final discrimination accuracy was 92.50%, the sensitivity was 90.65%, and the specificity was 94.62%.@*CONCLUSIONS@#Compared with the traditional probabilistic neural network, BP neural network, RBF neural network and the classification discriminant analysis function (Classify) in MATLAB, the proposed SA-PNN has higher accuracy, sensitivity and specificity for discriminating lung cancer and the adjacent normal tissues based on permittivity.
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Humans , Algorithms , Lung Neoplasms/diagnosis , Neural Networks, Computer , Sensitivity and SpecificityABSTRACT
Purpose: High Dose Rate (HDR) remote afterloading brachytherapy machine and advanced treatment planning system have made it possible to make variations in individual dwell times across a catheter according to tumour density and for sparing normal structures. New inverse planning technique such as Inverse Planning Simulated Annealing (IPSA) has also been introduced. But very few institutions are venturing towards volume based IPSA optimised intracavitary brachytherapy. This study focuses on dwell time deviation constraint (DTDC) feature of IPSA based optimization which restricts the large variation of dwell time across the catheter. Methods and Material: For this retrospective study we have generated IPSA optimised intracavitary brachytherapy plans for 20 cancer cervix applications. The initial DTDC value of each IPSA plan was kept 0.0. Later on gradual increment was made in DTDC values in step of 0.2. Plan modulation index (M) defined by Ryan L. Smith et al was used for characterising the variation of dwell time modulation with respect to gradual increase in DTDC parameter. Results: Plan modulation index gradually decreases with increasing value of DTDC from 0.0 to 1.0. There was the 83% decrease in M value from IPSA of DTDC 0.0 to fully constrained IPSA of DTDC1.0. There is reduction of 8.26% and 6.95% for D2cc values of rectum and bladder respectively for DTDC 1.0 compared to DTDC 0.0. Conclusions: One of the benefits of applying DTDC constrained in IPSA plan is that, it removes local hot spots. It's another advantage is the reduction in rectum and bladder dose.
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Objective To investigate effect of high dose irradiation on the performances of thermolumines-cence detectors (LiF:Mg, Cu, P). Methods The high-dose irradiated thermoluminescence detector was annealed by a thermoluminescence annealing furnace until the annealing was completed, and then the annealed thermoluminescent detector was irradiated 0.5Gy by 137Cs irradiator to verify the accuracy of the thermoluminescentdetector. Results The thermoluminescence detector after high-dose irradiation could not be completely annealed under the temperature condition of 240 ℃, and it could be completely annealed at a high temperature as 400℃. After 0.5 Gy irradiation by 137Cs irradiator, the measurement results of the annealed thermoluminescence detector were significantly smaller, and the dose response and dispersion of the detector were also changed significantly. Conclusions After a more than 5 Gy irradiation, the crystal structure of the thermoluminescence detector has changed, and a high temperature peak above 240 ℃ has appeared, which leads to the failure to completely anneal at normal temperature. Therefore, the thermoluminescence detector can no longer be used for dosimetry after high-dose irradiation.
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Objective To evaluate the effect of an inverse planning simulated annealing (IPSA) in the treatment of cervical cancer with combined intracavitary and interstitial three-dimensional brachytherapy.Methods A total of 60 patients with locally advanced cervical cancer who received both external beam radiotherapy and combined intracavitary and interstitial brachytherapy in our hospital from October 2016 to July 2018 were enrolled.Patients were divided into four groups with 15 patients each according to the number of needles applied (1,2,3,and 4 needles,respectively).Dosimetric distributions were optimized with both Graphical optimization (GRO) and IPSA.Paired t-test was applied to compare the dosimetric differences between plans optimized with GRO and IPSA.Results The Dg0 and V100 of IPSA plans were higher than those of GRO (t=-4.742,-4.823,P<0.05),while the conformity index (CI) and conformal index (COIN) were slightly lower than those of GRO plans (t=9.642,8.783,P<0.05).No significant difference in the V150,V200,V300 between IPSA and GRO (P>0.05) was observed.There was also no significant difference in the D2cm3 of bladder and rectum between IPSA and GRO (P>0.05).The difference of Dg0 between IPSA and GRO was increased as the number of implanted needles increased,which increased from 4 cGy to 14 cGy as the number of needle increased from 1 to 4.The difference of V100 between GRO and IPSA was also increased as the number of needle increased.Conclusions In the treatment of cervical cancer with combined intracavitary and interstitial threedimensional brachytherapy,IPSA plan could improve the target coverage(D90,V100)without increasing the dose to the OARs and high dose region in the target compared with GRO.With the numbers of needles increased,the advantage of IPSA increased in terms of target coverage.
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ObjectiveTo study the relationship between tumor siza,aource intensita,arescription dose and source dwell time in the after-loading treatment plaa,and to establish a method that can be used for rapid quality control of after-loading plans.Methods The all of gynecological cancer patients treated in this hospital were selected:84 cases of all three tubes of Fletcher applicator,58 cases of uterine alone and 39 cases of vaginal applicator.Each patient was scanned with CT before treatment.Contouring the target and organs at risa,ahe treatment plan was optimized using IPSA.Record the source strengta,arescription dosa,aource dwell tima,and tumor volume of the prescribed dose for each case.Calculate CI values and Rv.The kvalue analyzes the CI distribution characteristics and the correlation with the Rv value.In addition,46 cases of gynecologic tumor patients were used to verify the method.Results The fitting index of the after-loading scheme of the three applicators showed a normal distribution.The mean value of the Fletcher applicator CI was 0.720±0.067,the k value was 1 394,Rvalue was 0.894.The mean value of the uterine alone CI was 0.697±0.076,the k value was 1 428,R=0.940,the mean value of the vaginal applicator CI was 0.742± 0.067,the k value was 1 362,and R=0.909.Conclusions Using this methoa,at can quickly assess whether the planned target voluma,aadiation source intensita,arescription dose and treatment time matca,and find the cause of deviation based on the feedback results to ensure that the after-loading treatment plan can be quickla,accuratela,and efficiently implemented according to clinical requirements.
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OBJECTIVE: To optimize DNA extraction methods and PCR reaction parameters, and develop an excellent and accurate rapid detection reagent for Fetus Cervi. METHODS: The DNA of Fetus Cervi was extracted by the modified salting method, modified SDS method A and modified SDS method B. Four DNA polymerase were chosen from the market and compared with each other. The annealing temperature and annealing time were optimized by classical control variable method and intersected experiment. A rapid detection reagent of Fetus Cervi was developed and then evaluated. RESULTS: The A260 /A280 ratio of the DNA extracted by modified SDS method B was (1.74 ± 0.05), and the mass concentration was (0.250 ± 0.005) μg•L -1. With high fidelity Taq DNA polymerase, the PCR product concentration could reach (0.185 ± 0.005) μg•L-1. Through these experiments, the annealing temperature was set at 58 ℃ and the annealing time was 30 s. The rapid detection reagent course was established to quickly and accurately identify Fetus Cervi and their artefacts, with one clear and bright band at 563 bp. CONCLUSION: The rapid detection reagent of Fetus Cervi combines the optimal DNA extraction method and the optimal PCR reaction parameters, and can accomplish the identification of Fetus Cervi and its pseudo-products with high accuracy and specificity.
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Abstract It evaluated the effect of aging by Low Temperature Degradation (LTD), executed after post- processing surface treatments (polishing, heat treatment and glazing), on the surface characteristics (micromorphology and roughness) and on the structural stability (phase transformation and mechanical behavior-flexural strength and structural reliability) of a ground yttrium-stabilized tetragonal zirconia polycrystal (Y-TZP) ceramic. Discs of Y-TZP (VITA In-Ceram YZ) were manufactured (ISO:6872-2015; 15 mm in diameter and 1.2 ± 0.2 mm in thickness) and randomly assigned into 10 groups according two factors: "aging" in 2 levels (with or without) and "surface treatment" in 5 levels (Ctrl: as-sintered; Gr: grinding with coarse diamond bur; Gr + HT: grinding plus heat treatment; Gr + Pol: grinding plus polishing; Gr + Gl: grinding plus glazing). Roughness (n=30), biaxial flexural test (n=30), phase transformation (n=2), and surface topography (n=2) analyses were performed. Aging led to an intense increase in monoclinic (m) phase content for all the tested conditions, being the as-sintered samples (Ctrl= 65.6%) more susceptible to the t-m phase transformation. Despite of increasing the m-phase content, aging was not detrimental for characteristic strength (except to the grinding condition). There was no significant reduction in the Weibull modulus after surface treatments. Additionally, heat treatment and glazing after grinding led to a decrease in characteristic strength, while polishing presented the highest characteristic strength values. Thus, polishing is mandatory after grinding the Y-TZP ceramic, while performing glazing or heat-treatment alone after grinding lead to the worst mechanical performance.
Resumo Este estudo avaliou o efeito do envelhecimento através da degradação a baixas temperaturas (low temperaturare degradation - LTD) após a realização de tratamentos de superfície pós- sinterização (polimento, tratamento térmico e glaze) nas características superficiais (micromorfologia e rugosidade), e na estabilidade estrutural (transformação de fase e comportamento mecânico - resistência flexural e confiabilidade estrutural) de uma cerâmica de zircônia tetragonal policristalina estabilizada por ítria (Y-TZP) desgastada. Discos de cerâmica Y-TZP (VITA In-Ceram YZ) foram confeccionados (ISO:6872-2015; 15mm de diâmetro e 1,2 ± 0,2mm de espessura) e randomicamente divididos em 10 grupos de acordo com dois fatores: "envelhecimento" (com e sem) e "tratamento de superfície" (Ctrl - sem tratamento; Gr - desgaste com ponta diamantada grossa; Gr + HT - desgaste mais tratamento térmico; Gr + Pol - desgaste mais polimento; Gr + Gl - desgaste mais glazeamento). Foram realizadas as análises de rugosidade (n=30), flexão biaxial (n=30), transformação de fase (n=2) e topografia de superfície (n=2). O envelhecimento levou a um aumento intenso no conteúdo de fase monoclínica (m) em todas as condições testadas, sendo observada uma maior susceptibilidade de transformação de fase t-m nas amostras do grupo controle (Ctrl= 65.6%). Apesar de provocar elevada transformação de fase, o envelhecimento não apresentou efeitos negativos nos desfechos avaliados. Não houve redução significativa do módulo de Weibull após os tratamentos. Além disso, o tratamento térmico e o glaze após desgaste levaram a uma redução da resistência característica, enquanto que o grupo polimento apresentou o mais alto valor de resistência característica. O glaze e o tratamento térmico geraram o pior desempenho mecânico, portanto a realização do polimento após desgaste de uma cerâmica Y-TZP é obrigatória.
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Yttrium/chemistry , Zirconium/chemistry , Dental Materials/chemistry , Dental Polishing/methods , Surface Properties , X-Ray Diffraction , Materials Testing , Microscopy, Electron, Scanning , Microscopy, Atomic Force , Flexural Strength , Hot TemperatureABSTRACT
Aiming at the disadvantages of traditional direct aperture optimization (DAO) method, such as slow convergence rate, prone to stagnation and weak global searching ability, a gradient-based direct aperture optimization (GDAO) is proposed. In this work, two different optimization methods are used to optimize the shapes and the weights of the apertures. Firstly, in order to improve the validity of the aperture shapes optimization of each search, the traditional simulated annealing (SA) algorithm is improved, the gradient is introduced to the algorithm. The shapes of the apertures are optimized by the gradient based SA method. At the same time, the constraints between the leaves of multileaf collimator (MLC) have been fully considered, the optimized aperture shapes are meeting the requirements of clinical radiation therapy. After that, the weights of the apertures are optimized by the limited-memory BFGS for bound-constrained (L-BFGS-B) algorithm, which is simple in calculation, fast in convergence rate, and suitable for solving large scale constrained optimization. Compared with the traditional SA algorithm, the time cost of this program decreased by 15.90%; the minimum dose for the planning target volume was improved by 0.29%, the highest dose for the planning target volume was reduced by 0.45%; the highest dose for the bladder and rectum, which are the organs at risk, decreased by 0.25% and 0.09%, respectively. The results of experiment show that the new algorithm can produce highly efficient treatment planning a short time and can be used in clinical practice.
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Objective To compare and analyze the dosimetric discrepancy of combind intracavitary/interstitial brachytherapy using three different kinds of optimization method in locally advanced cervical cancer.Methods Totally 20 cases of locally advanced cervical cancer were selected and divided into three groups according to different optimization method which include manual optimization group (MO) based on graphical optimization,inverse planning simulated annealing (IPSA 1)based on simulated annealing optimization algorithm,IPSA 2 based on IPSA 1 with limitation on maximum dose of target.The dose volume histogram parameters of the targets (V200,V150,V100,D100,D90,HI) and the OARs(D0.1 cm3,D1 cm3 and D2 cm3) were analyzed.Results For CTV,compared with MO,there was no significantly statistical difference in D100between IPSA 1 and IPSA 2(P > 0.05).However,V200,V150,V100 and HI for ISPA1 were better than for ISPA2 (t =-3.422-9.910,P < 0.05).In addition,V100 and D100 in ISPA1 were better than in ISPA2 (t =7.238,5.032,P <0.05).For OARs,D0.1 cm3,D1 cm3 and D2 cm3 in rectum,bladder,sigmoid colon of both ISPA 1 and ISPA 2 were dramatically lower than those of MO (t =2.235 5.819,P < 0.05),without significantly statistical difference found between ISPA1 and ISPA2.Conclusions For combined intracavitary/interstitial brachytherapy in locally advanced cervical cancer,all treatment plans based on three different kinds of optimization methods can meet the clinical need.Moreover,inverse optimization can ensure dose coverage over target and reduce maximum dose of rectum,bladder and sigmoid colon.
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Abstract According to the Food and Agriculture Organization (FAO), roughly one-third of the total food produced is lost globally. The major cause of this wastage is the perishability of fruits and vegetables. Therefore, researchers have endeavored to develop an effective preservation technique. Our study explored the potential application of spider silk as an odourless and edible preservative coating for fruits. The spider silk was collected from spiders reared in the laboratory, following by degumming and dissolution to formulate the silk solution. For this study, apricots were selected as the model fruit. The apricots were dip coated with the formulated silk solution and allowed to dry. In order to enhance the beta sheet content of the silk coating, the fruits were exposed to water annealing for varying intervals of time under vacuum condition. The effect of silk coating and water annealing time period on preservation of fruits was then evaluated morphologically and gravimetrically. The results showed that the fruits, which were used as control, exhibited a greater degree of water loss and suffered from fungal attack. In contrast, the silk coated fruits showed less water loss and were protected from fungal attack. Therefore, the study provides compelling evidence regarding the application of spider silk as a preservative coating.
Resumo Segundo a Organização para Alimentação e Agricultura (FAO), cerca de um terço do total de alimentos produzidos é perdido globalmente. A principal causa deste desperdício é a perecibilidade das frutas e legumes. Portanto, os pesquisadores têm se esforçado para desenvolver uma técnica de preservação eficaz. Nosso estudo explorou a potencial aplicação de seda de aranha como um revestimento conservante inodoro e comestível para frutas. A seda da aranha foi coletada de aranhas criadas em laboratório, seguindo-se a degomagem e dissolução para formular a solução de seda. Para este estudo, os damascos foram selecionados como fruto modelo. Os damascos foram revestidos por imersão com a solução de seda formulada e deixados secar. A fim de aumentar o teor de folhas beta do revestimento de seda, os frutos foram expostos a recozimento de água durante vários intervalos de tempo sob condições de vácuo. O efeito do tempo de recobrimento de seda e recozimento de água na preservação de frutos foi então avaliado morfologicamente e gravimetricamente. Os resultados mostraram que os frutos, utilizados como controle, apresentaram maior grau de perda de água e sofreram ataque fúngico. Em contraste, os frutos revestidos de seda mostraram menos perda de água e foram protegidos contra ataques fúngicos. Portanto, o estudo fornece evidências convincentes sobre a aplicação de seda de aranha como um revestimento conservante.
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Objective To investigate the dosimetric difference between inverse planning simulated annealing(IPSA)and manual optimized plan for isodose line in interstitial brachytherapy for locally advanced cervical cancer and to provide a better optimization method for clinical application. Methods A total of 104 patients with cervical cancer were enrolled in this study. They received pelvic external beam radiotherapy and interstitial brachytherapy in five fractions. Both IPSA and manual optimized plan for isodose line were used to optimize the dose in each fraction. Dose volume parameters of the two plans were compared to analyze the dosimetric outcome by paired t-test. Results There were no significant differences in mean D 90and D 100for high-risk clinical target volume(HR-CTV)and D 90for intermediate-risk clinical target volume(IR-CTV)between the two groups(P>0.05). The IPSA group had a significantly higher D 100for IR-CTV than the manual optimized group(58.36±2.06 Gy vs. 53.99±2.17 Gy, P=0.025). For organs at risk,the IPSA group had a significantly lower mean rectum D 2ccand a significantly higher bladder D 2ccthan the manual optimized group(68.53± 2.85 Gy vs. 71.77± 1.79 Gy, P=0.002;80.49± 3.36 Gy vs. 78.71± 2.64 Gy,P=0.034). There was no significant difference in sigmoid D 2ccbetween the two groups(P>0.05). The IPSA group had significantly higher relative dose homogeneity index(HI)and conformity index (CI)of radiation dose for target volume than the manual optimized group(P<0.05), and there was no significant difference in overdose volume index(OI)between the two groups(P= 0. 1 0 7).Conclusions Compared with manual optimized plan for isodose line, IPSA can improve the dose distribution of tumor tissue,reduce mean rectum D 2cc,and increase CI and HI,so it is a preferable optimized treatment planning method in clinical application.
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Objective To improve the quality of personal dose equivalent measurement by exploring optimal annealing temperature conditions.Methods Totally 60 pieces of thermoluminescent detectors were randomly and equally divided into 6 groups.The 6 groups underwent 10-min annealing under 200,220,230,240,250 or 260 ℃ respectively,and then were cooled with the same conditions and went through measurement after irradiation by the calibrated radiation source.The above operation of annealing,cooling and measurement were repeated for 10 times,and the 6 groups were compared on dispersity,sensitivity and glow curve.Results Single test proved that under 240 ℃ the dispersity,sensitivity and glow curve gained optimal results comprehensively,while repeated tests showed that the dispersity had the optimal value under 250 ℃ and the sensitivity decreased significantly as the times of annealing rose.Conclusion Annealing conditions have to be selected according to the requirements of the thermoluminescent detector.
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Objective To improve the quality of personal dose equivalent measurement by exploring optimal annealing temperature conditions.Methods Totally 60 pieces of thermoluminescent detectors were randomly and equally divided into 6 groups.The 6 groups underwent 10-min annealing under 200,220,230,240,250 or 260 ℃ respectively,and then were cooled with the same conditions and went through measurement after irradiation by the calibrated radiation source.The above operation of annealing,cooling and measurement were repeated for 10 times,and the 6 groups were compared on dispersity,sensitivity and glow curve.Results Single test proved that under 240 ℃ the dispersity,sensitivity and glow curve gained optimal results comprehensively,while repeated tests showed that the dispersity had the optimal value under 250 ℃ and the sensitivity decreased significantly as the times of annealing rose.Conclusion Annealing conditions have to be selected according to the requirements of the thermoluminescent detector.
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Objective To establish a computer-aided diagnosis (CAD) model for the classification and diagnosis of systemic lupus erythematosus (SLE) complicated with renal involvement,and to provide a new method for the timely detection and diagnosis of the disease.Methods Simulated annealing(SA) algorithm was used to optimize the penalty coefficient C and kernel function parameter g of the support vector machines(SVM) algorithm before an SA-SVM classifier model was established and was applied to the intelligent assistant diagnosis of SLE.Results Unlike the single SVM classifier,this method never fell into local optimum,and improved the classification accuracy of a classifier.The classification accuracy for SLE with renal involvement was as high as 98.72%.Conclusion The experimental results show that this classification model is well applicable to the intelligent diagnosis of SLE with renal involvement.
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This paper is aimed to study the clustering method for Chinese medicine (CM) medical cases. The traditional K-means clustering algorithm had shortcomings such as dependence of results on the selection of initial value, trapping in local optimum when processing prescriptions form CM medical cases. Therefore, a new clustering method based on the collaboration of firefly algorithm and simulated annealing algorithm was proposed. This algorithm dynamically determined the iteration of firefly algorithm and simulates sampling of annealing algorithm by fitness changes, and increased the diversity of swarm through expansion of the scope of the sudden jump, thereby effectively avoiding premature problem. The results from confirmatory experiments for CM medical cases suggested that, comparing with traditional K-means clustering algorithms, this method was greatly improved in the individual diversity and the obtained clustering results, the computing results from this method had a certain reference value for cluster analysis on CM prescriptions.
Subject(s)
Algorithms , Cluster Analysis , Databases as Topic , Drug Prescriptions , Drugs, Chinese Herbal , Pharmacology , Reproducibility of ResultsABSTRACT
Objective To compare the differences and characteristics of the dose distribution of the two optimization methods in the three dimensional brachytherapy,and provide the basis for clinieal treatment.Methods Excel 2007 was used to generate random number.And a total of 21 patients of cervical cancer were selected from those who have completed the treatment.Inverse simulated annealing optimization (IPSA) plans were designed for graphical optimization (GO) plans.The dose volume histogram (DVH) parameters of the targets (V100%,V150%) and the organs (D1 cm3,D2cm3) of the two methods were analyzed.Results The targets dose of both plans could meet the prescription requirements.There was no statistically significant difference in the dose parameters of all targets (P > 0.05).The closes of D1 cm3 and D2cm3 in the bladder of IPSA plan were significantly lower than that of the GO plan (t =3.596,3.490,P < 0.05).There was no statistically significant difference in the dose parameters of rectum (P > 0.05).Conclusions For cervix brachytherapy,the GO and IPSA have no effect on targets dose,but IPSA optimization can reduce the maximum dose of bladder.