scholarly journals Application of microwaves in the convective drying of ceramic

Author(s):  
Kinga Rajewska ◽  
Andrzej Pawłowski

The paper demonstrates microwave and convective drying processes in different combinations of kaolin cylindrical samples in laboratory scale. Analysis of the kinetics and sample temperature evolution show that the moment of application and electromagnetic field duration have the biggest influence on characteristics of the drying curve and quality of dried material. Dried samples were subjected to strength tests using the Brazilian method in order to determine the relation between its quality and different drying programs. Keywords: ceramic, convective drying, microwave drying, strength test. 

Molecules ◽  
2019 ◽  
Vol 24 (16) ◽  
pp. 2900 ◽  
Author(s):  
Łyczko ◽  
Jałoszyński ◽  
Surma ◽  
García-Garví ◽  
Carbonell-Barrachina ◽  
...  

True lavender flowers (Lavandula angustifolia Mill.) is a critical source of essential oils and a flavouring agent used in numerous industries like foods, cosmetics and pharmaceuticals. Its main volatile constituents are linalool and linalyl acetate, which are commonly considered as main odour-active constituents (OACs). Nevertheless, the quality of true lavender flowers is highly dependent on its post-harvest treatment, mainly the preservation method. Recognising that drying is the most frequently used preservation method, the influence of various drying methods, including convective drying (CD) at 50, 60 and 70 °C, vacuum-microwave drying (VMD) with powers 240, 360 and 480 W and combined convective pre-drying at 60 °C followed by vacuum-microwave finish-drying with power 480 W (CPD-VMFD), on the quality of true lavender flowers was verified. The evaluation of influence was carried out by HS-SPME(HS, solid-phase microextraction), GC-MS, GC-MS-O (gas chromatography–mass spectrometry–olfactometry) techniques. Moreover, the sensory panel has assessed the sample odour quality. As a result, the optimal drying methods regarding the requirements for products were established. Overall, for total essential oil recovery, CD at 50 °C is the optimal drying method, while for odour quality concerning the sensory panel evaluation, VMD with power 360 W combined CPD-VMFD and CD at 50 °C is the optimal drying method.


Author(s):  
Neila Bahloul ◽  
M. A. Balti ◽  
M. S. Guellouze ◽  
Nabil Kechaou

The present study aims to find the best drying method to minimize the duration of the operation while respecting the nutritional value of the product. Experiments of convective drying and microwave radiation were respectively carried out with a convective dryer (heat temperature: 65 °C and air velocity: 1.3 m/s) and a microwave oven (power level: 100 W and frequency: 2450 MHz). Six coupling tests between the convective drying and microwave radiation were conducted. The only variable condition is the time output of tomatoes from the convective dryer or the microwave oven corresponding to an intermediate mass ratio (IMR) 0.5, 0.4 and 0.3. The microwave drying removes the bound water faster than convective drying. This explains the observed time savings due to convection-microwave and microwave-convection combined drying. The combination of convection drying and microwave drying to an IMR 0.5 preserved better the red color and the antioxidants of the tomato. Thus, the convection–microwave combined drying (IMR 0.5) proved most suitable for preserving the quality of tomatoes. Keywords: convective drying; microwave; coupled drying; color. 


Author(s):  
Ella Polozova ◽  
Vsevolod Skvortsov ◽  
Olga Radaykina ◽  
Mariya Narvatkina ◽  
Anastasiya Seskina ◽  
...  

The widespread prevalence of comorbid pathology determines the relevance of this problem. Comorbid pathology due to the interaction of diseases, drug pathomorphism, age characteristics of the patient, significantly changes clinical picture and course of the main nosology, affects severity of complications and their nature, significantly affects quality of life and prognosis of patients. Diagnosis and treatment of many diseases is complicated in the conditions of comorbidity. The article presents a clinical case of a comorbid patient with arterial hypertension from the moment of exposure to risk factors and ending with the formation of many concomitant diseases, as an example of trans-nosological comorbidity.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Vali Rasooli Sharabiani ◽  
Mohammad Kaveh ◽  
Roozbeh Abdi ◽  
Mariusz Szymanek ◽  
Wojciech Tanaś

AbstractTwo different drying methods were applied for dehydration of apple, i.e., convective drying (CD) and microwave drying (MD). The process of convective drying through divergent temperatures; 50, 60 and 70 °C at 1.0 m/s air velocity and three different levels of microwave power (90, 180, and 360 W) were studied. In the analysis of the performance of our approach on moisture ratio (MR) of apple slices, artificial neural networks (ANNs) was used to provide with a background for further discussion and evaluation. In order to evaluate the models mentioned in the literature, the Midilli et al. model was proper for dehydrating of apple slices in both MD and CD. The MD drying technology enhanced the drying rate when compared with CD drying significantly. Effective diffusivity (Deff) of moisture in CD drying (1.95 × 10−7–4.09 × 10−7 m2/s) was found to be lower than that observed in MD (2.94 × 10−7–8.21 × 10−7 m2/s). The activation energy (Ea) values of CD drying and MD drying were 122.28–125 kJ/mol and 14.01–15.03 W/g respectively. The MD had the lowest specific energy consumption (SEC) as compared to CD drying methods. According to ANN results, the best R2 values for prediction of MR in CD and MD were 0.9993 and 0.9991, respectively.


2020 ◽  
Vol 32 (S1) ◽  
pp. 8-8
Author(s):  
K. Thorsen ◽  
M. C. N. Dourado ◽  
A. Johannessen

AbstractBackground:Awareness of dementia is examined in different scientific fields as significant for assessment of diagnosis, and for treatment and adaptation to the disease. There are very few longitudinal studies of individual experiences of awareness among people with dementia, related to quality of life.Aim:To examine how younger people (< 65 years) with dementia (YOD) express awareness of the dementia and how, over time, they seem to handle awareness as a strategy to preserve quality of life.Method:A longitudinal qualitative study with individuals with YOD was performed with interviews every six months over five years for a maximum of ten interviews. The interviews were analysed by modified grounded theory.Findings:Awareness is a complex, multidimensional concept. Awareness of dementia is predisposed by personality, life history and established coping styles. The main coping styles – live in the moment, ignore the dementia, and make the best of it – seem to be rather consistent throughout the progression of the disease. Transitions in life situation, such as moving to a nursing home, may change the individual’s awareness of dementia.Conclusion:Unawareness of dementia may have an important adaptive function to preserve quality of life. To increase awareness must be approached with reflexivity and the utmost sensitivity.


2021 ◽  
pp. 073346482199686
Author(s):  
Candace L. Kemp ◽  
Alexis A. Bender ◽  
Joy Ciofi ◽  
Jennifer Craft Morgan ◽  
Elisabeth O. Burgess ◽  
...  

Meaningful engagement is an important dimension of quality of life and care for persons living with dementia, including the growing number who reside in assisted living communities. This report presents preliminary findings from an ongoing qualitative study aimed at identifying best care practices to create and maintain meaningful engagement among persons with dementia. Over a 1-year period, we conducted interviews, residents’ record review, and participant observations in four diverse care communities. Our analysis identified four approaches that successfully promote meaningful engagement: (a) knowing the person, (b) connecting with and meeting people where they are, (c) being in the moment, and (d) viewing all encounters as opportunity. Incorporation of these approaches in care routines and adoption by all care partners can promote meaningful engagement, including during crises such as COVID-19.


2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0011
Author(s):  
Adam Weaver ◽  
Dylan Roman ◽  
Maua Mosha ◽  
Nicholas Giampetruzzi

Background: The standard of care in ACL reconstruction (ACLR) typically involves standardized strength testing at 6 months or later to assess a patient’s readiness to return to play (RTP) using isokinetic and isometric testing, and functional strength testing. Recent literature suggests that isokinetic knee extension strength should demonstrate 89% limb symmetry index (LSI) or greater prior to returning to sport. However, there is little known on the effects of strength testing early in the rehabilitation process and the relationship to strength test performance at time of RTP. Purpose: The purpose of this study was to examine how early post-operative strength test performance impacts isokinetic strength outcomes at RTP testing in adolescents. Methods: The retrospective cohort study included patients undergoing primary ACLR between 12 and 18 years of age, early post-operative strength measures, and isokinetic dynamometer strength at RTP from July 2017 and April 2019. Data was dichotomized into desired outcomes at 3 months: >70% isometric knee extension LSI, > 20 repetitions on anterior stepdown test (AST), > 90% LSI Y Balance. At RTP testing, isokinetic knee extension strength data was categorized into >89% LSI at 3 speeds (300, 180, 60°/sec). Chi square testing and odds ratio statistics were used to examine association and its magnitude. Results: 63 patients met inclusion criteria (38 females; 15.37±1.66 years old). >70% LSI isometric knee extension strength at 3 months showed a significant association (Table 2) and demonstrated the strongest odds of having >89% LSI on isokinetic strength tests at all 3 speeds at RTP with 180°/sec being the highest (OR=14.5; 95% CI=4.25,49.43; p= <0.001). Performance on AST showed a significant association (χ2 (1, n=63) = 17.00, p <0.001), and highest odds at 180°/sec (OR=4.61; 95% CI = 1.59, 13.39, p=<0.001) and 60°/sec (OR= 3.07; 95% CI = 1.10, 8.63, p= 0.04). Combination of performance on isometric strength tests and AST showed a significant association to isokinetic strength at all three speeds, but less predictive then isometrics in isolation. (Table 2). There was no significant relationship between YBR LSI at 3 months and isokinetic strength at 6 months. Conclusion: Standardized strength testing early in rehabilitation can help identify patients that will successfully complete RTP testing. Our results suggest that isometric knee extension strength and timed anterior stepdown test provide meaningful clinical information early in the rehabilitation process. This data also suggests that the use of YBAL for predicting isokinetic strength performance is limited. [Table: see text][Table: see text]


2020 ◽  
Vol 22 (4) ◽  
pp. 183-191
Author(s):  
O. T. Kotsoeva ◽  
A. V. Koltsov ◽  
V. V. Tyrenko ◽  
A. A. Ialovets

This review discusses a number of aspects of surgical methods for treating severe chronic heart failure: resynchronizing therapy, mechanical circulatory support systems, and heart transplantation. Surgical methods for the treatment of heart failure are a rapidly developing field of modern cardiology and cardiac surgery. The main surgical method of treatment was and remains orthotopic transplantation of a donor heart. The advent of implantable systems has affected the problem of heart transplantation. Over the past decade, the use of mechanical circulatory support systems has grown significantly. At the moment, there are 3 main directions: creating devices for auxiliary blood circulation, various modes and methods of electrical stimulation of the myocardium, creating devices that mechanically remodel the heart chambers (left ventricle). All of these directions to some extent (depending on the evidence base) have found their place in modern recommendations for the treatment of chronic heart failure. The use of mechanical left ventricular remodeling shows good results in patients suffering from symptomatic heart failure, which leads to a significant and persistent decrease in the volume of the left ventricle and improvement of its function, symptoms and quality of life. Despite the fact that at the moment the geography and prevalence of their use is small, the number of implanted devices will only grow. Thus, given the need for frequent hospitalizations and high treatment costs, it is necessary to improve modern methods of surgical treatment of severe and terminal heart failure, make them more accessible, which will affect the duration and quality of life of these patients.


Author(s):  
R.O. Ogureshnov ◽  

This article discusses the problem of assessing the effectiveness of the rehabilitation process. The assessment of the effectiveness of the rehabilitation process is recognized by many researchers as one of the most difficult in the theoretical substantiation of the process of rehabilitation and habilitation, in this regard, there are no uniform approaches to assessing the effectiveness of rehabilitation today. The article presents studies by several authors on this issue. Rehabilitation of patients after a stroke most often occurs with the use of rehabilitation complexes. The possibility of applying the assessment of the effectiveness of rehabilitation to such complexes is very relevant, since at the moment there is no unified system for determining the quality of rehabilitation complexes.


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