Microwave Disinfection Research Articles

A q-Rung Orthopair Fuzzy FUCOM Double Normalization-Based Multi-Aggregation Method for Healthcare Waste Treatment Method Selection

Healthcare waste (HCW) management is an intricate issue upon which numerous factors, such as technical, economic, environmental, and social factors, have an impact. A determination on the best treatment method for HCW management can be viewed as a challenging multi-criteria decision-making (MCDM) problem in which various options and evaluation criteria are considered. One critical concern when assessing HCW treatment (HCWT) methods is the representation and treatment of dubious data. In this paper, we present a q-rung orthopair fuzzy full consistency method double normalization-based multi-aggregation methodology called q-ROF-FUCOM-DNMA to solve MCDM problems with q-rung orthopair fuzzy information (q-ROFI). In the proposed approach, criteria weights are estimated through the full consistency method (FUCOM) and a ranking of the alternatives is obtained through the double-normalization-based multi-aggregation (DNMA) method with q-ROFI. A HCWT method assessment issue was considered in order to clarify the relevance of the proposed approach. Five HCWT methods, including chemical disinfection, microwave disinfection, incineration, autoclaving (steam sterilization), and reverse polymerization, were considered as alternatives. The results show that autoclaving (steam sterilization) is the most efficient HCWT method. Furthermore, we performed a sensitivity analysis to determine the stability of the proposed approach. Additionally, we compared the presented approach with existing methods.

Compact reversed Cherenkov radiation oscillator with high efficiency

An all-metal metamaterial slow-wave structure (MSWS), which comprises a hollow circular waveguide loaded by periodically arranged complementary electric split-ring resonators (CeSRRs), is proposed. Due to the CeSRRs with the characteristics of both subwavelength and strong resonance, the MSWS has both compact size and high interaction impedance relative to conventional SWS. Based on the reversed Cherenkov radiation in the MSWS, a compact reversed Cherenkov radiation oscillator (RCRO) with high efficiency is developed. The measured electronic efficiency is 19.54%, and measured output power is 10.16 kW at 2.221 GHz under the conditions that the beam voltage is 26 kV, the beam current is 2.0 A, and axial magnetic flux density is ∼962 G. The experimental results clearly show that the brand-new RCRO can be applied to large-scale scientific facilities, medical imaging, microwave heating, microwave disinfection and sterilization, and so on.

A randomized controlled study comparing the efficacy of soap versus soap-plus-microwave disinfection for irrigation device in children with acute rhinosinusitis.

Nasal irrigation is an effective component of sino-nasal disease management. Nonetheless, bacterial contamination is worrisome. To study bacterial colonization incidence using squeeze-bottle nasal irrigation devices, after disinfection with soap or soap-plus-microwave technique, in pediatric acute rhinosinusitis. A randomized, prospective, controlled study was conducted on acute rhinosinusitis children, aged 2-15 years. Each participant was randomized into a soap-cleaning or soap-plus- microwave group. For a two-week period, participants irrigated their nostrils with NSS twice daily and cleaned the bottle after each use. In the end, bottles were sent to a microbiological laboratory for bacterial identification. The mean 5S Score and satisfaction score gradually improved in both groups with no significant differences between groups. Bacterial identification frequency in the soap group was slightly higher than in the soap-plus-microwave one, without statistical significance. For safety and tolerability, all participants reported 100% adherence to nasal irrigation. The soap-plus-microwave group reported more minor adverse outcomes than the soap-cleaning one. No thermal deformation of irrigation bottles was observed. Regular cleaning of nasal irrigation devices is needed to minimize bacterial contamination. Only soap or soap plus microwave disinfection appeared simple and safe for disinfection. Both techniques can equally minimize the rate of bacterial contamination. Although no gross thermal deformation at optimal power and duration, chemical irritants after high power or long microwave durations may be a concern.

Experimental study on the disinfection of microbial contamination by the microwave radiation on a typical filter coated with absorbing material

In the air-conditioning system, a high-efficiency air filter can guarantee the capture of dust and biological particles. However, the traditional filter material itself does not have the function of disinfection and self-purification. As a result, the traditional air filter might become a hotbed for the reproduction of the microorganisms. Carried by the airflow, these microorganisms can enter the indoor environment, which might cause secondary pollutions. A properly selected upstream filter can prevent the particulate pollution, while it is hard to prevent the biological pollution inside the air-conditioning system. The microwave radiation is a broad-spectrum and high-efficiency disinfection method because of its disinfection mechanism, penetrability and selective heating property. At present, the microwave disinfection technology is widely used in the disinfection process of food processing, but its application in the air-conditioning field is relatively rare. From this point of view, this paper proposes to apply the microwave disinfection technology to the filters of the air-conditioning system. First, the combination of the filter and absorbing material is proposed to improve its absorption capacity of the microwave. Then, the air-conditioning system experimental platform for microwave disinfection was established and experiments were carried out to explore the disinfection effect of the Staphylococcus aureus on the composite filter under the microwave radiation. Finally, the experimental results and their influencing factors are briefly analyzed.

How Many Microwave Disinfection Cycles is Safe for the Adaptability of Polymethyl Methacrylate (PMMA) Denture Base Materials?: An In Vitro Study

Introduction: We aimed to determine the maximum microwave disinfection cycles that is safe for the adaptability of polymethyl methacrylate (PMMA) denture bases under power–time setting of 630 W for 3 minutes. Materials and Methods: Thirty PMMA maxillary denture bases were constructed and divided into two groups, control (no disinfection) and test (microwave disinfection at 630W for 3 minutes in water immersion). Coltene Rapid Liner (Coltene/Whaledent AG, Altstatten, Switzerland) silicone was coated onto the internal surface of the samples followed by placement of 8 kgf of axial load. The silicone film was removed, and weighed using analytical balance. One day interval was given between each cycle and samples were stored in 37°C water bath. Tests were carried out until a statistically significant silicone film weight change detected. The data were analyzed on SPSS version 21.0 (IBM Corp, Armonk, NY). Results: Statistically significant change of the denture base was detected after the tenth cycle of microwave irradiation. Conclusion: The maximum microwave disinfection cycles that is safe for the adaptability of PMMA denture bases under power–time setting of 630 W for 3 minutes is only up to 10 cycles.

ELECTROMAGNETIC RADIATION THERAPY EFFECT ON DIMENSIONAL STABILITY OF DENTURE BASES AND ITS ORAL HEALTH IMPACT ON DAILY PERFORMANCE

Background: The demonstration of moderately simple sterilization-disinfection measures in daily practice is very serious to decrease the probabilities of cross-infection as prosthetic appliances have to be sterilized prior to be transferred to the technician and patient. The used disinfection method should be properly selected due to its great effect on the physical and mechanical properties of denture bases. Aim: This research was conducted to study the consequences of chemical and electromagnetic radiation disinfection methods on dimensional stability and oral health impact on daily performance. Also, to evaluate the effect of repeated microwave disinfection under different conditions. Materials and Methods: Group I: Denture disinfection using (1%) sodium hypochlorite for 10 minutes. Group II: Denture disinfection using electromagnetic radiation (650 W for 3 minutes / once per week) and divided into 2 subgroups: Group II-A: Dentures kept dry during microwave disinfection. Group II-B: Dentures kept wet in distilled water during microwave disinfection. Group III: Denture disinfection using electromagnetic radiation (650 W for 3 minutes / twice per week) and divided into 2 subgroups: Group III-A: Dentures kept dry during microwave disinfection. Group III-B: Dentures kept wet in distilled water during microwave disinfection. Dimensional stability and patient satisfaction using (OIDP) questionnaire were evaluated after one- and three-weeks follow-up periods. Results: Comparison between dimensional changes after 1st & 3rd week revealed insignificant difference in dimensional changes regarding Group I (expansion) & GII-A & GII-B (Shrinkage) after 3rd week as P > 0.05. On the other hand, there was a significant difference (shrinkage) in GIII-A & GIII-B after the 3rd week as P<0.05. Oral health impact on daily performance (OIDP) revealed insignificantly decreased after 3rd week in all groups except GIII-B as OIDP significantly decreased. Conclusion: Complete denture disinfection with sodium hypochlorite preparation showed the least dimensional change (Expansion) with higher patient satisfaction, while electromagnetic radiation treatment (microwave) of complete dentures showed higher dimensional change with lower patient satisfaction especially in wet conditions.

Comparison of Repeated Chemical and Microwave Disinfection on Dimensional Accuracy of Gypsum Casts

OBJECTIVE: The aim of this experimental study is to compare the dimensional accuracy of gypsum casts after repeated disinfection in microwave at 900 Watts, 2450 MHz (5 minutes) and immersion in 0.5% Sodium hypochlorite (10 minutes). Disinfecting casts is recommended to prevent cross infection but may cause dimensional changes. During fabrication of prosthesis, a cast may get contaminated several times so there is a need of repeated disinfection. METHODOLOGY: Sample size was 33 (11 in each group), calculated through WHO software for sample size determination by using standard deviation of 0.16 at 95% confidence interval and 80% power of study. Impressions in irreversible hydrocolloid were recorded of an acrylic cast fabricated for this study. The impressions were poured with die stone and were randomly divided into 3 groups; Group I: Microwave disinfection, Group II: Immersion disinfection in 0.5% Sodium hypochlorite, Group III: Control group. For Groups I and II, each cast was disinfected 7 times with 5 minutes interval between two disinfection cycles, after every cycle anteroposterior and mediolateral measurements were recorded using digital Vernier caliper (accuracy upto 0.01 mm). For group III, casts were rinsed with distilled water, dried in open air within temperature range of 28+/-2OC for 10 mins followed by anteroposterior and mediolateral measurements. This procedure was repeated seven times for each cast. RESULTS: Anteroposterior and Mediolateral differences of dimensional change between and within the Group A, B and C was calculated by One Way ANOVA. Inter/intra examiner reliability was taken into consideration at the time of study. Mean dimensional change in the casts were insignificant through six disinfecting cycles. However, in the seventh cycle, a significant difference (p=0.003) was observed in the anteroposterior dimension (0.03% dimensional change for Group A and 1.26 % for Group B whereas, in mediolateral dimension, dimensional change was 0.35% for Group A and 0.59% for Group B (p=0.004). Dimensional change of >0.5% was considered as the cutoff value for casts to be considered as dimensionally accurate. Casts disinfected through immersion disinfection did not produce dimensionally inaccurate casts in anteroposterior dimension after third cycle and in seventh cycle in mediolateral dimension. However, result is significant only in seventh cycle. Microwave disinfection produced dimensionally accurate casts throughout all cycles. CONCLUSION: Microwave disinfected casts remained dimensionally stable compared to immersion disinfection. KEYWORDS: Disinfection, microwave, immersion, dimensional stability, gypsum casts

Does microwave disinfection affect the dimensional stability of denture base acrylic resins? A systematic review.

To systematically evaluate the effect of microwave disinfection on the dimensional stability of denture base acrylic resins. Microwave disinfection has been considered as an alternative method for disinfecting complete dentures to help prevent and treat denture stomatitis. However, data on the impact of microwave disinfection on the dimensional stability of acrylic resins are still scarce. The PubMed/Medline, SCOPUS and EMBASE databases were searched in order to assess articles published in English up to January 2021 (CRD42021212267). We included studies that have assessed the effect of microwave disinfection, on the dimensional stability of acrylic resins, comparing them with negative or positive controls. A total of seven in vitro studies were included. The qualitative synthesis demonstrated that, in general, microwave disinfection produced more distortion on the materials than do immersion in sodium hypochlorite, chloride solution, chlorhexidine, and water immersion. However, considering the dimensional stability of the specimens, microwave disinfection at 500W for 3minutes, and at 450W for 5minutes, produced similar or better outcomes than did control groups. In general, microwave disinfection promotes changes in the dimensional stability of denture base acrylic resins, and should thus be used with caution. However, microwave disinfection protocols at lower power settings (500 and 450W) and exposure times (3 and 5minutes) produces similar or less distortion than chemical disinfection. More studies are still required in order to evaluate the clinical and long-term implications of microwave disinfection.

Effectiveness of the “Sterius 60” SHF Radiation Installation for Disinfection of Objects Contaminated with PBA of Groups I–IV, when Working with Infected Biomodels

The aim was to evaluate the effectiveness of using the “Sterius 60” microwave disinfection system (Russia) for decontamination of objects infected with PBA of groups I–IV emerging as a result of working with infected laboratory animals.Materials and methods. Effectiveness verification of disinfection of biological waste generated as a result of the life of laboratory animals by SHF radiation was carried out in the microwave system “Sterius 60”, recommended by the manufacturer for disinfection of epidemiologically hazardous and extremely dangerous medical waste, including biological ones (classes B and C), by volumetric SHF heating. Carcasses of uninfected laboratory animals (white mice, Guinea pigs, suckling rabbits), granulated feed and bedding material (wood shavings), which are objects directly in contact with biomodels, were used as vivarium waste to be decontaminated. The following microorganisms were utilized as model test ones: Bacillus subtilus VKM B-911, Bacillus stearothermophilus VKM B-718, Bacillus licheniformis G VKM B-1711-D, Alcaligenes faecalis 415, Yersinia pestis EV, Bacillus anthracis STI. Laboratory utensils (plastic Petri dishes, porcelain mortars and pestles) were used as a mock-up chamber filler for model test microorganisms.Results and discussion. As a result of the study, data were obtained indicating that the microwave system for disinfection of medical waste “Sterius 60” is ineffective for decontamination of biological waste in laboratories working with biomodels infected with PBA of groups I–II. The established standard mode of disinfection of this system was effective only for non-spore forms of microorganisms, pathogenicity groups III–IV. Therefore, in our opinion, it is advisable to use it for decontamination of laboratory utensils infected with PBA of groups III–IV, directly at sites of waste generation.

Effectiveness of denture microwave disinfection for treatment of denture stomatitis: A systematic review and meta-analysis.

The aim of this systematic review was to evaluate the effectiveness of removable complete denture disinfection using microwaves for the treatment of denture stomatitis. This review identified studies comparing the efficacy of microwave prosthesis disinfection (I) to topical antifungal therapy (C) in the treatment of denture stomatitis (O), which included only individuals who used complete dentures and presented with denture stomatitis (P). The search was performed in six databases and identified 1524 records; after the removal of duplicates, 816 articles remained. Three articles were selected for qualitative synthesis and two for meta-analysis. Random-effects meta-analysis estimated the polled effects of microwave disinfection and antifungal therapy on the Candida counts and clinical manifestation of denture stomatitis. The GRADE approach was used to estimate the certainty of evidence. All included studies reported significant reductions in Candida counts and the frequency of denture stomatitis of groups subjected to microwave disinfection of dentures and topical antifungal therapy with nystatin. Significative differences between treatments were only detected for Candida quantification in the palate, within 90days follow-up period (SMD=0.47, 95% CI=0.02-0.91). Meta-analyses did not show any further differences between treatments (p>.05), considering the Candida quantification in dentures and the frequency of clinical signs of denture stomatitis. The certainty of the evidence was considered as low, according to GRADE approach. Microwave disinfection of complete dentures can be considered as efficient as antifungal therapy for the treatment of denture stomatitis. However, further well-designed studies are necessary to confirm such evidence.

The effectiveness of microwave disinfection in treating Candida-associated denture stomatitis: a systematic review and metaanalysis.

To evaluate the effectiveness of microwave disinfection in treating Candida-associated denture stomatitis (CADS). The PubMed/MEDLINE, Embase, and Scopus databases were searched for reports on randomized clinical trials (RCTs) published in English until May 2020 (PROSPERO CRD42020192062) that evaluated the treatment of CADS by using microwave disinfection. The main outcomes were the improvement of clinical signs and/or the decrease in the residual yeast present on the dentures and palatal mucosa. The mean differences, standard deviations, risk ratio, and 95% confidence interval were calculated by using the random-effects model. Heterogeneity was assessed by using Cochran's Q test and I2 values. The level of significance was set at α = 0.05. Five RCTs with 245 participants were included. The descriptive investigations demonstrated that microwave disinfection was as effective (p > 0.05) as 0.2% chlorhexidine, 0.02% sodium hypochlorite, and topical nystatin (100.000 IU/mL), and was superior to topical miconazole in treating CADS. The metaanalysis did not show a statistical difference between microwave disinfection and nystatin (100.000 IU/mL) treatment in terms of mycological counts, cure, and recurrence rates (p > 0.05). Microwave disinfection showed comparable results with those of conventional therapies for treating CADS. In addition, treatment with 650 W for 3 min once a week for 14 days had better cost-effect results, indicating both the prevention and treatment of CADS. Our findings provide evidence regarding the treatment of CADS using microwave disinfection, and also indicating the best cost-effective option for this treatment modality.

Sustainability assessment of healthcare waste treatment systems using surrogate weights and PROMETHEE method.

This study aims to assess the sustainability of healthcare waste treatment systems using surrogate weights and the Preference Ranking Organization METHod for Enrichment Evaluations (PROMETHEE). For this purpose, ten treatment systems, including land disposal, incineration and non-incineration systems, were evaluated in terms of environmental, financial, social, and technical criteria. Firstly, fifteen reputed experts assigned their preferred rankings for the groups of criteria and the sub-criteria. The conversion of these rankings into numerical weights was performed using the SR function, which is an additive combination of Sum and Reciprocal weight functions. Secondly, the alternatives' performance with regards to each criterion allowed PROMETHEE to generate the outranking flows for each alternative. The complete ranking revealed that the rotary kiln (A4) is the most sustainable system followed by steam disinfection (A8), dry heat disinfection and microwave disinfection. However, the municipal landfill is the least sustainable system, while chemical disinfection is ranked in the penultimate position of sustainability. The partial ranking indicated that A4 and A8 are incomparable and both were ranked as most sustainable. Therefore, the sustainability of a system cannot be assessed properly without the exact specification of the system itself. In addition, it is preferable to act on the criteria that affect negatively the system to improve its performance.

Evaluación de la resistencia a la tracción del acrílico después de la desinfección con agua ozonizada y microondas.

Background: There is a need for safe disinfection methods without a detrimental effect on the acrylic denture base. Aim: the purpose of the current study was to evaluate the effect of ozonated water and two protocols of microwave disinfection on tensile bond strength of high-impact acrylic. Material and methods: Eighty samples were divided into four major groups: one control and three experimental groups, 20 specimens each. The experimental groups each received either disinfection by ozonated water, microwave 850W/1min, or microwave 650W/6min. Further division of the major groups into two sub-groups depending on the number of disinfection cycles and total immersion time in distilled water: One cycle and one day versus seven cycles and seven days. The control group specimens were immersed in distilled water without any disinfection for either one day or seven days. Tensile strength testing was performed on the specimens from the eight groups. The data were analyzed by SPSS version 21#. The ANOVA and Tukey-HSD multiple comparison tests were used for comparison for groups. Results: A non-significant difference in the tensile strength was observed in the groups subjected to one cycle of ozone or microwave disinfection at 850W/1min. There was a significant decrease in tensile strength for the specimens subjected to one cycle of 650W/6min microwaving. The number of testing cycles and storage time in distilled water had a significant impact on the tensile strength of the acrylic in all tested groups, by decreasing it. Conclusion: Ozone disinfection and microwaving at 850W for one minute did not affect the tensile strength of the acrylic, but repeated disinfection over seven days at one cycle per day impaired the tensile strength of the acrylic resin.

Numerical Analysis of the Microwave Treatment of Palm Trees Infested With the Red Palm Weevil Pest by Using a Circular Array of Vivaldi Antennas

The Red Palm Weevil (RPW) is one of the most dangerous pests of palms in the world. Among several techniques that have been applied to combat the RPW pest such as phytosanitation, chemical insecticides, pheromone traps and biological control, the use of microwave energy for heat disinfestation seems to be a promoting solution. Its main advantages are rapid heat transfer, volumetric and selective heating, speed of switching on and off and no pollution to the environment. This article presents the design of microwave antenna system for microwave disinfection of date palms application. The microwave system consists of a 3-D circular array of 16 Vivaldi elements. We present an electromagnetic-thermal model, including palm and adult/Larva RPW models, to test their thermal reactions for microwave heating. The 3-D numerical model shows the capability of the microwave system to heat the outer layer of the palm, and reach the RPW lethal temperature. Also, the research discusses the effect of varying the input power and treatment duration to control the RPW. This work provides a powerful tool to simulate the thermal distribution of the palm and RPW insects for different input cases; which help fight against the RPW.

Evaluation of Microwave and Ozone Disinfections on the Color Characteristics of Iranian Export Raisins Through an Image Processing Technique

Raisins are one of the most important Iranian export products but are threatened by various storage pests. Because of the disadvantages of fumigants, we evaluated alternative microwave and ozone methods for their disinfection and the side effects on raisin qualities. To perform microwave disinfection, the studied raisin samples were exposed to microwave powers of 450, 720, and 900 W for 20, 30, 40, and 50 s. Also, ozone treatments included various combinations of ozone concentrations (2, 3, and 5 ppm) and exposure times (15, 30, 45, 60, and 90 min). An image processing technique was implemented to determine the color changes of raisins in terms of lightness, redness, yellowness, total color difference, chroma, and hue angle. The results revealed that increasing the microwave power and exposure time might lead to further changes of the previously mentioned color characteristics. Compared with the microwave treatments, ozone treatments had fewer effects on those features. Generally, microwave and ozone methods could successfully disinfect Oryzaephilus surinamensis in raisins, with acceptable changes in all the color characteristics. Hence, the previously mentioned methods are proposed as alternative chemical fumigants.

The development of the environmentally safe method for disinfection and biostimulation of spring wheat seeds using electro-magnetic field of super-high frequency

The article presents the laboratory experiment results aimed at determining the effective modes of electro-magnetic field of super-high frequency (EMFSHF) and their impact on the laboratory germination of spring wheat seeds, reducing the infection by the most harmful microorganisms. In the conditions of high seeds contamination in the Krasnoyarsk territory, the developed technology of microwave disinfection of spring wheat seeds is relevant due to its efficiency and environmental friendliness. The analysis of the results shows that the effective mode of the microwave field in which the infection of wheat grain with phytopathogenic microflora in the established thresholds of harmfulness, along with the simultaneous preservation of sowing qualities, is the variant with Psp = 650 W/dm3 and τ = 90 – 60 seconds.

EVALUATION AND COMPARISON OF THE INFLUENCE OF MICROWAVE AS A DISINFECTANT METHOD ON THE COLOUR STABILITY, MECHANICAL AND PHYSICAL PROPERTIES OF THERMOPLASTIC (BREFLEX) AND ACRYLIC RESINS DENTURE BASE MATERIAL

Microwave radiation has been used for sterilization and disinfection of dental prosthesis which considered as an alternate method for chemical disinfectants.Aim: to evaluate the influence of microwave as a disinfection procedure on the colour ,the transverse strength and dimensional stability on the thermoplastic resin denture base and compare it with two types of conventional acrylic resin at different exposure times Material and methods: 180 samples were made, 60 for each of the next tests (colour, transverse strength and dimensional stability) .The samples of each test, were subdivided into three groups each group has 20 samples according to the denture base material used (Breflex thermoplastic resin, heat cure and self cure). Each test were divided into four groups, one control and the other groups according to the time of microwave disinfection that were utilized (5,10,15 minutes) at 650 watt. Colour, transverse strength and dimensional stability parameters were measured with and without disinfection. Data were analyzed with ANOVA and Post-hoc Tukey’s tests with statistically significant at p ≤ 0.05 . Result: Microwave disinfection had no significant influence on the colour, the transverse strength beside the dimensional changes of all denture base materials at all the disinfection intervals, except it has a significant influence on the colour of heat cure for 15 minutes. Breflex showed a significantly increase in the flexural strength also, improvement in its fitness to the casts when compared with both heat and self cured resins after treated with microwave. Conclusion: Microwave can be used safely for disinfection of all the denture base material except heat cure for 15 minutes. Breflex is the best due to it has no influence on its colour , increase the flexural strength, as well as dimensionally stable when compared with both heat and self cured acrylic resins

Methodology for multicriteria assessment and selection of an effective method of grain disinfection

High-quality crop products should not contain extraneous and dangerous substances of both natural and artificial origin. Natural contaminants include parasitic micro-fungi and bacteria; artificial ones include chemical compounds in the form of pesticides and fertilizers. Pesticides, in one way or another solving the problem of disinfection, are themselves very dangerous. In addition, their constant use leads to mutations of parasitic microorganisms in the direction of extremely stable species, i.e. the problem of resistance. To avoid these shortcomings, there are alternative disinfection methods based on various types of electromagnetic energy. A variety of such methods raises the purpose of their objective assessment, including in comparison with chemical etching. This determined the purpose of the study, which consists in developing a scientifically based methodology for multicriteria assessment and choosing an effective method of grain disinfection. The object of the study was the chemical and electrophysical methods of disinfection, the subject of the study - the patterns of choosing the best of them. The novelty was made up of the stages of the methodology: structuring the attribute space, compiling a hierarchical diagram of groups of attributes, determining weighting factors and estimates based on the specifics of agricultural production. In mathematical tools, the maximum sum of weighted estimates method is used, according to which the integral criterion F is calculated. The technique is suitable for any disinfection methods with any number of signs and alternatives. An example of its application for four alternatives is given: chemical etching, microwave disinfection, SHV disinfection, disinfection with a low-frequency magnetic field (LMF). At the same time, the advantage of the LMF method was established, which received the maximum integral estimate F = Fmax = 0,864. The conclusions are drawn about the reliability of the methodology, the possibility of its application in an expanded space of signs, which gives an updated assessment.

Microwave Disinfection of Biohazardous Carcasses

<p><em><em>A Medister microwave device specifically developed for thermal disinfection of infectious waste was assessed concerning its efficacy for the disinfection of biohazard us animal carcasses. Employment of animals for the experiments was avoided by simulation of carcasses with deep frozen nutrient agar contaminated with bacillus subtilis spores. At a disinfection time of 45 minutes, the reduction rate of the spores was 7.90-8.58 decimal power levels. Controlled microwave disinfection is thus a valuable alternative tool for the treatment of contaminated carcasses.</em></em></p>

Effect of disinfection techniques on physical-mechanical properties of a microwave-activated acrylic resin

Abstract The effects of disinfection by microwave irradiation and immersion in peracetic acid on the physical-mechanical properties of a microwave-activated acrylic resin were evaluated. Specimens of acrylic resin were divided into a control group (specimens not disinfected) and 2 test groups subjected to one disinfection method: microwave irradiation at 850 W for 1 minute or immersion in 50 mL of 0.2% peracetic acid for 5 minutes. Specimens were submitted to Knoop hardness, flexural strength, flexural modulus, Izod impact, water sorption and solubility, glass transition temperature, and degree of conversion tests. Microwave disinfection significantly increased the mean Knoop hardness, Izod impact strength, water sorption, water solubility and glass transition temperature, whereas the flexural properties remained unaffected. Microwave disinfection increased the degree of conversion. Peracetic acid disinfection showed no changes in any properties. Both disinfection techniques did not adversely affect the evaluated properties.