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The rust flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is the most prevalent pest in stored food for human and animal consumption. The current study was conducted to determine the efficacy of microwave energy and gamma radiation on T. castaneum larvae, pupae, and adults. Microwave was applied with exposure times of 30, 60, 120, 180, 240, and 300 sec. at the powers of 180, 300, and 450 W. In addition, gamma radiation was applied at a dosage of 200, 400, 600, 800, and 1000 Gray. Mortality percentage was recorded after 1, 2, 3, 4, 7, and 10 days, and LD50 was recorded after 7 days of treatment. The results indicated that the mortality of T. castaneum increased with increasing doses and exposure time. The mortality of T. castaneum increased, reaching 100% at power levels of 300 s and 450 W. The LT50 and LT90 decreased as power levels and exposure time increased. Moreover, the dosage of 1000 Gray caused 85.0 and 65.0% mortality after 7 days of irradiation for larvae and adult stages. The required dosage of gamma radiation to kill 50% (LD50) of adults after 7 days was 580.1 Gray. Therefore, the use of microwave energy and gamma radiation is a very important alternative method to protect stored grains and their products against T. castaneum. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the effect of the convective and microwave dying methods on the colour parameters (L*, a*, b*, C, α and ΔE) and rehydration ratio of bay leaves. Drying experiments were conducted using 350 and 460W of microwave powers and air temperatures of 50, 60 and 70ºC. Different microwave powers show significant effect on colour of dried bay leaves. Increasing microwave power, a* (redness/greenness), α (hue angle) and ΔE (total colour changes) values increased whereas L* (lightness), b* (yellowness/blueness) and C (Chroma) values decreased. For the convective drying, although there are changes in the values of the colour parameters (L*, a*, b*, C and α), there are no significant differences in the values of the total colour changes (ΔE) statistically (P>0.05). The effect of microwave power levels and air temperature on rehydration characteristics was determined. It was found that the rehydration ratio values decreased with an increasing temperature and increasing power levels. The highest rehydration ratio was recorded for the samples dried at 350W and the lowest ratio was seen in a sample dried at 70°C. Microwave drying can be a practical drying process, an alternative to convective drying for drying bay leaves. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The extraction yield of oil from milk thistle seeds intensified upon the microwave pretreatment. • Treated seeds oil showed the highest oxidative stability after the microwave pretreatment. • Microwave pretreatment declined the polyunsaturated to saturated fatty acids ratio of all samples. • The amount of tocopherols and phytosterols increased remarkably in treated seeds oil. • Chlorophyll and total phenolic content and saponification value increased in treated samples. Abstract In this study, seeds of Milk thistle (Silybum marianum L.) as a biomedical plant were pretreated with microwaves (800 W) for 2 and 4 min, to evaluate the process of intensifying oil extraction efficiency, physicochemical properties, nutraceuticals content, and fatty acids profile of milk thistle seeds oil extracted from Iranian ecotype, Khoreslo. Results showed that microwave pretreatment of Milk thistle seed increased the oil extraction yield (by 6%), total phenolic content (by 12.2%), phytosterols (by 25%), and tocopherols (by 37.5%) of the oil obtained by solvent. Some physicochemical properties of seed oil such as chlorophyll content (0.55–1.73 mg pheophytin/kg oil) and saponification value (179–187 mg KOH/g oil) increased, but acid value (4.24−2.16 mg KOH/g oil), peroxide value (5.11−2.09 meqO 2 /kg oil), iodine value (107−99 g I 2 /100 g oil), and the poly unsaturated to saturated fatty acids (PUFA/SFA) ratio of all samples decreased by treatment with microwaves. Moreover, the α, β, γ-, δ δ -tocopherols, and phytosterols content such as cholesterol, campesterol, stigmasterol, cleroesterol, β-sitosterol, and Δ7-sterol of milk thistle seed oils increased by microwaves treatment. In conclusion, the results indicated that microwave pretreatment is a promising strategy for amplification of oil extraction yield and the content of nutraceuticals in obtained oil from milk thistle seeds. [ABSTRACT FROM AUTHOR]

Highlights • Controlled and defined microwave radiation for enhancing tomato productivity. • Microwave radiation showed increment in the bioactive compounds. • Stimulation in germination rate and seedling vigour of the tomato seedlings through microwave radiation. • Adoption of microwave radiation in superior agronomic approach to ensure the food supplies keep pace with population growth. Abstract The present study was undertaken to explore the stimulatory effect of microwave radiation on growth and development of Lycopersicon esculentum Mill. (tomato) plant. These signal stimuli propagate and encode information which alters and manipulate the plant signaling system. Two varieties of tomato seeds i.e. NS-585 and NS-2535 were exposed to microwave radiation at 9.3 GHz for 0–8 h where 0 h seeds were treated as control. Exposure to microwave radiation showed enhanced germination rate and speed germination index and increment in the β-1,3-glucanase activity which clearly suggested the stimulation of the germination rate and seedling vigour of the tomato seedlings. Microwave radiation showed increment in the bioactive compounds like polyphenol and flavonoid, chlorophyll, carotenoid and protein content of the tomato plant exposed for 4–5 h; further increase in the microwave dose reduced the growth and other biochemical content in the tomato plant. Growth related modification in tomato seedlings were characterized using FT-IR spectroscopy which clearly confirmed the increase in pectin, lignin, protein, carbohydrate and lipid content in the microwave irradiated tomato seedlings. It is suggested that controlled and defined microwave radiation may help in enhancing crop productivity. [ABSTRACT FROM AUTHOR]

In the present work, the impact of microwave pretreatment on the thermal degradation of color (chlorophylls) in mustard greens was studied. The drying experiments were conducted in the range of temperatures from 50 to 80°C. The degradation in the levels of chlorophylls has been quantified using Hunter color values (L*, a*, and b*) and calculating total color difference (ΔE). From the color results, the changes in color values (L*, a*, and b*) were observed as inappreciable, and changes in ΔE were found to be increased during drying. Analysis of kinetic data displayed a first-order reaction kinetics for chlorophyll degradation. Arrhenius equation was used to calculate the activation energies for rate constants, and it has been varied from 13.3 to 27.4 kJ/mol. Thermodynamic parameters, enthalpy of activation (ΔH#), and entropy activation (ΔS#) were found to be in the range of 1.40-2.63 J/mol and −293 to −305 J/mol · K, respectively. The data from the present work revealed that the microwave pretreatment of mustard greens remarkably influenced the retention of chlorophylls in the final dehydrated powder. [ABSTRACT FROM AUTHOR]

An efficient and rapid regiospecific approach for the synthesis of cyclic and acyclic nucleosides of 2-oxonicotinonitriles was performed. Whereas, glycosylation of 2-oxonicotinonitriles 1a, b with peracetylated sugars (namely, peracetylated glucose, galactose and ribose) under MWI tolerated exclusively the desired N-nucleosides 2a, b, 4a, b and 6a, b in significant yields (75-86%) and in short reaction time (5-7 min.). The same products were obtained under the conventional conditions, using halo-sugar with low yields in hard conditions. Similarly, the acyclic nucleosides 8a, b and 9a, b were obtained under MWI and conventional conditions via reaction of 1a, b with 4-bromo butyl acetate and 2-acetoxyethoxymethyl bromide. Finally, deprotection of the latter blocked N-nucleosides was performed via treatment with aqueous methanolic solution containing a catalytic amount of triethyl amine to give the desired free nucleosides 3a, b, 5a, b, 7a, b, 10a, b and 11a, b, respectively. The free nucleosides (3a, b, 5a, b, 7a, b and 11a, b) were evaluated against Gram (+ ve) bacteria, Gram (-ve) bacteria and one pathogenic Fungi namely, Aspergillus flavus. Good results were obtained for compounds 7a, b and 11a, b compared with the used standard drugs (Cefotaxime and Dermatin).Graphical abstract: [ABSTRACT FROM AUTHOR]

To explore how autophagy changes and whether autophagy is involved in the pathophysiological process of synaptic plasticity injury caused by microwave radiation, we established a 30 mW/cm 2 microwave-exposure in vivo model, which caused reversible injuries in rat neurons. Microwave radiation induced cognitive impairment in rats and synaptic plasticity injury in rat hippocampal neurons. Autophagy in rat hippocampal neurons was activated following microwave exposure. Additionally, we observed that synaptic vesicles were encapsulated by autophagosomes, a phenomenon more evident in the microwave-exposed group. Colocation of autophagosomes and synaptic vesicles in rat hippocampal neurons increased following microwave exposure. Conclusion: microwave exposure led to the activation of autophagy in rat hippocampal neurons, and excessive activation of autophagy might damage synaptic plasticity by mediating synaptic vesicle degradation. [ABSTRACT FROM AUTHOR]

MIL-101(Cr) metal–organic framework samples were successfully synthesized through the conventional electrical heating (CE), ultrasound (US), and microwave (MW) synthetic methods at three different temperatures and various synthesis times. These were done with the aim of understudying the crystallization kinetics of these complex MIL’s structures. The nucleation and crystal growth steps were thus, quantified through measuring the relative crystallinity of the prepared MIL-101(Cr) utilizing the PXRD and FESEM analysis under various synthesis conditions. In addition, the textural properties of the fully crystallized samples measured through the N 2 adsorption–desorption isotherms at 77 K. The rates of these steps estimated from crystallization curves revealing changes of relative crystallinity with synthesis time. The activation energies ( E a ) and pre-exponential factors ( A ) of each step calculated from their corresponding Arrhenius plots. This demonstrated that the rate of crystallization steps ( i.e., both nucleation and crystal growth) downgraded in the order of CE ≪ MW < US. Moreover, it turned out that increasing of pre-exponential factors played more important role in accelerated crystallization under MW and US conditions in comparison to lowering of the activation energies. Hence, it was suggested that physical effects ( i.e., hot spots) were playing more important role in comparison to the chemical ones ( i.e., acidity of the reaction medium) in the accelerated synthesis of the MIL-101(Cr) utilizing US and MW techniques. [ABSTRACT FROM AUTHOR]

Reaction of sodium (E/Z)-2-(2-(1-cyano-2-methoxy-2-oxoethylidene)hydrazinyl)benzene-sulfonate (NaHL) with copper(II) nitrate hydrate in the presence of imidazole (im) in methanol affords [CuL(im)(H 2 O)] ( 1 ). Complex 1 is characterized by IR spectroscopy and ESI-MS spectrometry, elemental and single crystal X-ray crystal structural analyses. The coordination environment of the central copper(II) is nearly intermediate between ideal square-based pyramidal and trigonal bipyramidal geometry, three sites being occupied by the L 2− ligand, which chelates in the O, N, O fashion, while two other sites are filled with the water and imidazole molecules. Extensive intermolecular hydrogen bonds between the L 2− , water and imidazole ligands lead to a 3D supramolecular network. 1 and known Cu(II) complexes [Cu(H 2 O) 2 L]·H 2 O ( 2 ), [Cu(H 2 O)(py)L]·H 2 O ( 3 ) and [Cu 3 (µ 3 -OH)(NO 3 )(CH 3 OH)(µ 2 -X) 3 (µ 2 -HL)] ( 4 ) act as effective catalysts in the oxidation of cyclohexane to cyclohexanol and cyclohexanone, using low power microwave (MW) irradiation, under mild conditions. Without a promoter, the activity of the catalyst reached a turnover number of 1.44 × 10 3 and a turnover frequency of 1.98 × 10 3  h −1 , after 2 h, at 50 °C. [ABSTRACT FROM AUTHOR]

The use of extensive, time-consuming synthesis and the cost of an additional element in synthesis makes difficult the synthesis of photocatalyst active under a broad wavelength range. We propose a synthesis method to obtain ZnO nanoparticles in distinctive morphologies, which lie to several photocatalytic activation conditions. The Zn precursor concentration, solvent, temperature and reaction time altered the ZnO particles morphologies. Although all synthesis parameters modification interferes in ZnO particle morphology, the most pronounced was Zn salt precursor concentration. The synthesis parameter did not interfere in the crystalline wurtzite ZnO phase and the optical characterization, indicating possibilities of ionic defects formations in ZnO lattice. The “3-D flower like” ZnO structure reaches 98% of discoloration under UV illumination and 42% under visible illumination of initial rhodamine-B concentration. The good UV and visible photocatalytic active confirms that with only the modification of synthesis method without any dopant element, ZnO structure is active in large wavelength range. [ABSTRACT FROM AUTHOR]

Microwave (MW) radiation induced oxidative stress reduces dendritic arborization, spine density and number of hippocampal pyramidal neurons and hence, impair learning and spatial memory through p53-dependent/independent apoptosis of hippocampal neuronal and nonneuronal cells. However, the mechanisms responsible for MWradiation induced impairment in memory formation remains still unknown. This study elucidates the effect of short (15 days) and long-term(30 and 60 days) low level 2.45 GHz MWradiation-induced local stress on the hippocampal spatial memory formation pathway in adult male mice. Twelve-weeks old mice were exposed to 2.45 GHzMWradiation (continuous-wave with overall average Power density of 0.0248 mW/cm2 and overall average whole body SAR value of 0.0146 W/Kg) @ 2 h/d for 15, 30, and 60 days. Learning and spatial memory was assessed by 8-arm radial maze. We have investigated the alterations in serum corticosterone level and the expression of glucocorticoid receptor, corticotropin-releasing hormone (CRH), inducible nitric oxide synthase (i-NOS), iGluRs, PSD-95-neuronal NOS (n-NOS) system, protein kinase A, protein kinase Ce- ERK1/2-pERK1/2 in all the hippocampal subregions, viz. CA1, CA2, CA3, and DG through immunohistochemistry/ immunofluorescence and alterations in the expression of hippocampal glucocorticoid receptor, CRH-receptor 1 (CRH-R1), cAMP-response element-binding (CREB), and phosphorylated-CREB (p-CREB) through western blot analysis. We observed that 2.45 GHz MWirradiated mice showed slow learning and significantly increased number of working and reference memory errors in radial maze task. Further, 2.45 GHzMW radiation exposure increases serum corticosterone level and the expression of CRH, CRH-R1, and i-NOS, while the expression of iGluRs, n-NOS, PSD-95, protein kinase Ce, protein kinase A, ERK-p-ERK, CREB, and p-CREB decreases in above mentioned hippocampal subregions in a duration dependent manner. Our findings led us to conclude that 2.45 GHzMWradiation exposure induced local stress suppresses signaling mechanism(s) of hippocampal memory formation. [ABSTRACT FROM AUTHOR]

Summary: Microwave radiation could increase the expression of pro‐inflammatory cytokines in rat Sertoli cells, which may impair spermatogenesis. However, the mechanisms that microwave radiation induces the cytokine expression in Sertoli cells remain to be clarified. The activation of TLRs by their ligands can trigger a common signalling pathway to upregulate inflammatory cytokines such as IL‐1, IL‐6, IL‐12 and TNF‐α. Microwave radiation can increase the expression of TLRs in lymphocytes. The purpose of this study was to determine the effect of microwave radiation on the TLRs in rat testis. We focus on the effect of TLR2‐5 (which is expressed relatively highly) by microwave radiation. The results showed that the expression of TLR2‐5 and the pro‐inflammatory cytokines (IL‐1β, IL‐6 and TNF‐α) was increased both in mRNA and in protein. Furthermore, p‐p38, p‐ERK1/2, p‐JNK and p‐NF‐κB p65, the key factors of TLR signalling, were also elevated by microwave exposure. And the NF‐κB can be induced more dominantly. These results suggest that TLRs signalling can be activated by microwave radiation in testis, which may provide the molecular basis for the in‐depth study. [ABSTRACT FROM AUTHOR]

A concise and efficient one-pot synthesis of 3-functionalized 4-hydroxycoumarin derivatives via a three-component domino reaction of 4-hydroxycoumarin, phenylglyoxal and 3-arylaminocyclopent-2-enone or 4-arylaminofuran-2(5H)-one under catalyst-free and microwave irradiation conditions is described. This synthesis involves a group-assisted purification process, which avoids traditional recrystallization and chromatographic purification methods. Keywords: 3-functionalized 4-hydroxycoumarin; multi-component domino reaction; catalyst-free; group-assisted purification process derivatives via a three-component domino reaction of 4-hydroxycoumarin, phenylglyoxal and 3- arylaminocyclopent-2-enone or 4-arylaminofuran-2(5H)-one under catalyst-free and microwave irradiation conditions is described. This synthesis involves a group-assisted purification process, which avoids traditional recrystallization and chromatographic purification methods. [ABSTRACT FROM AUTHOR]

This paper evaluates the effect of glasses on the Specific Absorption Rate (SAR) and the absorbed power in the human head exposed to microwave from wireless eyewear device at phone call state. Due to the sensitivity of eyes to microwave, this paper mainly concentrates on the SAR and the absorbed power in ocular tissues. The calculated results indicate that wearing glasses can obviously increase the maximal SAR and the absorbed power in ocular tissues. Glasses has almost doubled the maximal SAR in ocular tissues. The absorbed power with glasses is about 3.1-4.5 times as big as that without glasses. Furthermore, we find that the maximal SAR and absorbed power are sensitive to the width of glass leg and the thickness of spectacle lens, while variation trends with the varying glasses size are quite different. Hypermyopia patient might suffer from higher risk of getting the oculopathy due to the larger SAR caused by the thicker spectacle lens. In conclusion, wearing glasses may pose higher health risk on eyes of wireless eyewear device user. This paper would provide valuable reference data for the future evaluation of microwave biological effect on eyes. [ABSTRACT FROM AUTHOR]

An efficient synthetic methodology for construction of 5-substituted 1 H-tetrazoles under microwave irradiation in green medium is described. With [Cu(phen)(PPh)]NO as catalyst and HO-isopropyl alcohol (IPA) as reaction medium, various substituted nitriles underwent (3 + 2) cycloaddition reaction with NaN under microwave irradiation to provide corresponding 5-substituted 1 H-tetrazoles in high yield. This method is not only efficient and general but also benefits from high functional group tolerance. This environmentally friendly synthetic methodology is visualized as an alternative to existing procedures, providing a simple route to privileged scaffolds. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Objective The long term effects of continuous microwave exposure cannot be ignored for the simulation of the real environment and increasing concerns about the negative cognitive effects of microwave exposure. Methods In this study, 220 male Wistar rats were exposed by a 2.856 GHz radiation source with the average power density of 0, 2.5, 5 and 10 mW/cm 2 for 6 min/day, 5 days/week and up to 6 weeks. The MWM task, the EEG analysis, the hippocampus structure observation and the western blot were applied until the 12 months after microwave exposure to detect the spatial learning and memory abilities, the cortical electrical activity, changes of hippocampal structure and the NMDAR subunits expressions. Results Results found that the rats in the 10 mW/cm 2 group showed the decline of spatial learning and memory abilities and EEG disorders (the decrease of EEG frequencies, and increase of EEG amplitudes and delta wave powers). Moreover, changes of basic structure and ultrastructure of hippocampus also found in the 10 and 5 mW/cm 2 groups. The decrease of NR 2A, 2B and p-NR2B might contribute to the impairment of cognitive functions. Conclusions Our findings suggested that the continuous microwave exposure could cause the dose-dependent long term impairment of spatial learning and memory, the abnormalities of EEG and the hippocampal structure injuries. The decrease of NMDAR key subunits and phosphorylation of NR 2B might contribute to the cognitive impairment. [ABSTRACT FROM AUTHOR]

The effect of Pb 2+ substitution on structural, magnetic and microwave properties of Ba 0.5 Sr 0.5 Fe 12 O 19 was investigated. Samples were synthesized using solid state reaction route with 1 wt% B 2 O 3 addition which was used as a catalyst for better crystal growth. Both lattice parameters (a and c) and crystallite sizes increased initially with Pb substitution and then they started to decrease according to the calculations based on Rietveld Refined XRD patterns. Magnetic properties of Pb substituted samples degraded compared to Pb-free hexaferrite, for instance, coercivity decreased substantially from 3.35 to 1.4 kOe. On the other hand, Pb 2+ substitution enhanced microwave absorption properties of the samples, for example the reflection loss increased from −40 dB to −57.5 dB in a 2 mm-thick Ba 0.3 Sr 0.4 Pb 0.3 Fe 12 O 19 sample. The mechanisms of microwave absorption appeared to be natural resonance of magnetic moments and relaxation of electrical dipoles for the reflection loss observed at high frequencies (>10 GHz) and quarter wave cancellation at matching thickness at frequencies ≤ 10 GHz. There is a very good agreement between experimentally measured and calculated matching frequency values for thicknesses between 2 and 5 mm. Finally, it was observed that matching thickness decreases exponentially with matching frequency in the 2–10 mm thickness range. [ABSTRACT FROM AUTHOR]

The contents of cyclins A1, B1, E1, and D1, cyclin-dependent kinases 2 and 4 (CDK2 and CDK4), cyclin-dependent kinase 2C inhibitor (p18), and cyclin-dependent kinase 1C inhibitor (p57) in whole blood mononuclear cells of practically healthy donors and convalescents from community-acquired pneumonia were measured after cell exposure to low-intensity electromagnetic radiation of 1 GHz. The level of cyclins A1, D1, and B1, p57, and p18 proteins, and CDK2 was reduced in convalescents, while the content of cyclin B1 was elevated in both groups. A strong correlation was found between the content of cyclin B1 and the levels of cyclin A1 and CDK2 in convalescents. Single exposure of whole blood cells to 1-GHz microwaves was accompanied by an increase in the content of the analyzed factors (particularly, cyclins A1 and E1). These data indicate that radiation induced activation of the synthetic phase of the cell cycle. [ABSTRACT FROM AUTHOR]

CoMgFe O nanoparticles with x values 0, 0.5, and 1 were synthesized using a microwave-assisted combustion method and subsequent heat treatment. The stoichiometric mixture of Co(NO)⋅ 6HO, Fe(NO)⋅ 9HO, Zn(NO)⋅ 6HO, and urea was used as the fuel additive. The structural, morphological, and magnetic properties of synthesized nanoparticles were then investigated using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and vibrating sample magnetometer analysis techniques. The mean crystal size of the synthesized samples was about 32 nm based on Scherrer's formula. The saturation magnetizations ( M ) were also 59, 27, and 28 emu/g for samples with x values 0, 0.5, and 1, respectively. Results showed direct changes in coercivity and remanent magnetization parameters by increasing the Co content, which can be attributed to the anisotropic nature of cobalt. [ABSTRACT FROM AUTHOR]

Purpose:To clarify whether extremely low-level microwaves (MW) alone or in combination with p38 inhibitor affect immune cell responses to inhalation exposure of mice to low-level toluene. Materials and methods:The cytokine profile, heat shock proteins expression, and the activity of several signal cascades, namely, NF-κB, SAPK/JNK, IRF-3, p38 MAPK, and TLR4 were measured in spleen lymphocytes of mice treated to air-delivered toluene (0.6 mg/m3) or extremely low-level microwaves (8.15–18 GHz, 1μW/cm2, 1 Hz swinging frequency) or combined action of these two factors. Results:A single exposure to air-delivered low-level toluene induced activation of NF-κB, SAPK/JNK, IFR-3, p38 MAPK and TLR4 pathways. Furthermore, air toluene induced the expression of Hsp72 and enhanced IL-1, IL-6, and TNF-α in blood plasma, which is indicative of a pro-inflammatory response. Exposure to MW alone also resulted in the enhancement of the plasma cytokine values (e.g. IL-6, TNF-α, and IFN-γ) and activation of the NF-κB, MAPK p38, and especially the TLR4 pathways in splenic lymphocytes. Paradoxically, pre-exposure to MW partially recovered or normalized the lymphocyte parameters in the toluene-exposed mice, while the p38 inhibitor XI additionally increased protective activity of microwaves by down regulating MAPKs (JNK and p38), IKK, as well as expression of TLR4 and Hsp90-α. Conclusions:The results suggest that exposure to low-intensity MW at specific conditions may recover immune parameters in mice undergoing inhalation exposure to low-level toluene via mechanisms involving cellular signaling. [ABSTRACT FROM AUTHOR]

The aim of this study is to explain the mechanism of the effect of low-level modulated microwave radiation on brain bioelectrical oscillations. The proposed model of excitation by low-level microwave radiation bases on the influence of water polarization on hydrogen bonding forces between water molecules, caused by this the enhancement of diffusion and consequences on neurotransmitters transit time and neuron resting potential. Modulated microwave radiation causes periodic alteration of the neurophysiologic parameters and parametric excitation of brain bioelectric oscillations. The experiments to detect logical outcome of the mechanism on physiological level were carried out on 15 human volunteers. The 450-MHz microwave radiation modulated at 7, 40 and 1000 Hz frequencies was applied at the field power density of 0.16 mW/cm2. A relative change in the EEG power with and without radiation during 10 cycles was used as a quantitative measure. Experimental data demonstrated that modulated at 40 Hz microwave radiation enhanced EEG power in EEG alpha and beta frequency bands. No significant alterations were detected at 7 and 1000 Hz modulation frequencies. These results are in good agreement with the theory of parametric excitation of the brain bioelectric oscillations caused by the periodic alteration of neurophysiologic parameters and support the proposed mechanism. The proposed theoretical framework has been shown to predict the results of experimental study. The suggested mechanism, free of the restrictions related to field strength or time constant, is the first one providing explanation of low-level microwave radiation effects. [ABSTRACT FROM PUBLISHER]

Previously, we have suggested that cell hydration is a universal and extra-sensitive sensor for the structural changes of cell aqua medium caused by the impact of weak chemical and physical factors. The aim of present work is to elucidate the nature of the metabolic messenger through which physiological solution (PS) treated by non-thermal (NT) microwaves (MW) could modulate heart muscle hydration of rats. For this purpose, the effects of NT MW–treated PS on heart muscle hydration, [3H]-ouabain binding with cell membrane,45Ca2+uptake and intracellular cyclic nucleotides contentsin vivoandin vitroexperiments were studied. It is shown that intraperitoneal injections of both Sham-treated PS and NT MW–treated PS elevate heart muscle hydration. However, the effect of NT MW–treated PS on muscle hydration is more pronounced than the effect of Sham-treated PS.In vitroexperiments NT MW–treated PS has dehydration effect on muscle, which is not changed by decreasing Na+gradients on membrane. Intraperitoneal injection of Sham- and NT MW–treated PS containing45Ca2+have similar dehydration effect on muscle, while NT MW–treated PS has activation effect on Na+/Ca2+exchange in reverse mode. The intraperitoneal injection of NT MW–treated PS depresses [3H]-ouabain binding with its high-affinity membrane receptors, elevates intracellular cAMP and decreases cGMP contents. Based on the obtained data, it is suggested that cAMP-dependent signaling system serves as a primary metabolic target for NT MW effect on heart muscle hydration. [ABSTRACT FROM PUBLISHER]

Objectives: Separate exposure to microwaves (MWs) or heat had effects on expression levels of Bax and Bcl-2 and sperm parameters in studied group. Aims: The objectives of this research were to determine the effects of separate and combined exposure to 900-MHz MW (as representative of cell phone radiation) and heat on gene expression and spermogram of male mice. Settings and Design: This experimental animal study was conducted in the school of public health. Materials and Methods: The study was done on 12 male mice randomly divided into four groups (21-23 g): control, test group 1 with separate exposure to 900-MHz MW, test group 2 with separate exposure to hot and sultry climate, and test group 3 with simultaneous whole body exposures to 900-MHz MW and hot and sultry climate. In all studied groups, gene expression and sperm parameters were measured. Results: Tissue samples in all test groups showed integrity of the seminiferous tubule followed by all types of germ line cells. Significant increases in the number of dead sperms in mice with separate exposure to heat were observed in comparison with the other studied groups (P < 0.05). The ratio of Bax expression was elevated to 0.015 ± 0.006 in mice after combined exposures to 900-MHz MW and heat. Conclusion: Separate and combined exposure to 900-MHz MW and heat may induce adverse effects on sperm parameters and gene expression of studied male mice. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of ultrasonic and microwave disintegration on physico-chemical and biodegradability properties of waste-activated sludge (WAS) from a municipal wastewater treatment plant. Another aim was to carry out particle size distribution (PSD) analysis as an integral component of sludge characterization to highlight the transformation mechanisms involved in pretreatment processes and better understand the biodegradation patterns of sonicated and irradiated WAS liquids examined by means of respirometric measurements. Various combinations of sonication and microwave irradiation parameters were applied to optimize operating conditions. The optimum ultrasonic density was determined as 1.5 W/mL, and energy dosages lower than 30,000 kJ/kg TS resulted in a fairly linear increase in the soluble chemical oxygen demand (SCOD) release. An irradiation time of 10 min and a temperature of 175°C were selected as the optimum microwave pretreatment conditions for sludge liquefaction. The most apparent impact of ultrasonication on the PSD of COD was the shifting of the peak at the particulate fraction (>1600 nm) toward the lowest size range (<2 nm). Microwave heating at the selected experimental conditions and ultrasonic pretreatment at 30,000 kJ/kg TS exhibited comparable size distribution and biodegradation characteristics to those of domestic sewage. [ABSTRACT FROM PUBLISHER]

The effects of conventional-C, carbon fiber plate assisted cabinet heater-CPAC, ohmic-OT, and microwave thawing-MT techniques on changes of some quality characteristics and resistant starch (RS) content of potato ( Solanum tuberosum L.) cubes (18 × 18 × 18 mm) were investigated. The effects of blanching prior to the freezing on thawing characteristics were also determined. The thawing times of non-blanched samples were determined as 23,580 ± 485 s, 5360 ± 40 s, 205 ± 18.25 s and 19.26 ± 1.49 s for conventional, CPAC, OT, and MT methods, respectively. The blanching process increased the thawing times in general. OT and CPAC thawing methods served lower RS content for thawed potato samples. The potato cubes thawed by OT and MT were softer than C and CPAC thawed potato cubes ( P < 0.05). The highest color change was found for MT of blanched samples and conventional thawing of non-blanched samples. The electrical methods could be alternative thawing methods in terms of providing shorter thawing times and desirable changes on some quality characteristics. Practical Applications The conventional thawing of high amount of frozen food products have posed a problem for catering industry. The long thawing time, drip loss issues, quality loses and possible microbial spoilage are lacks of conventional thawing method. The electroheating methods such as ohmic, microwave and unique carbon fiber plate assisted cabinet heating were employed as alternative thawing techniques. Thawing time of potato cubes were shortened and quality characteristics, such as drip loss, texture profile, color properties and resistant starch (RS), were improved by novel thawing methods. The obtained results reveal that the application of alternative thawing methods may lead to decreasing of the operating cost due to shorter process time and minimizing the changes in color, texture and nutritional compounds. [ABSTRACT FROM AUTHOR]

The feasibility of using ultrasonic Nakagami imaging to evaluate thermal lesions induced by microwave ablation (MWA) in ex vivo porcine liver was explored. Dynamic changes in echo amplitudes and Nakagami parameters in the region of the MWA-induced thermal lesion, as well as the contrast-to-noise ratio (CNR) between the MWA-induced thermal lesion and the surrounding normal tissue, were calculated simultaneously during the MWA procedure. After MWA exposure, a bright hyper-echoic region appeared in ultrasonic B-mode and Nakagami parameter images as an indicator of the thermal lesion. Mean values of the Nakagami parameter in the thermal lesion region increased to 0.58, 0.71 and 0.91 after 1, 3 and 5 min of MVA. There were no significant differences in envelope amplitudes in the thermal lesion region among ultrasonic B-mode images obtained after different durations of MWA. Unlike ultrasonic B-mode images, Nakagami images were less affected by the shadow effect in monitoring of MWA exposure, and a fairly complete hyper-echoic region was observed in the Nakagami image. The mean value of the Nakagami parameter increased from approximately 0.47 to 0.82 during MWA exposure. At the end of the postablation stage, the mean value of the Nakagami parameter decreased to 0.55 and was higher than that before MWA exposure. CNR values calculated for Nakagami parameter images increased from 0.13 to approximately 0.61 during MWA and then decreased to 0.26 at the end of the post-ablation stage. The corresponding CNR values calculated for ultrasonic B-mode images were 0.24, 0.42 and 0.17. This preliminary study on ex vivo porcine liver suggested that Nakagami imaging have potential use in evaluating the formation of MWA-induced thermal lesions. Further in vivo studies are needed to evaluate the potential application. [ABSTRACT FROM AUTHOR]

Taking into account different literature reports on microwave (MW) effects on living organisms, we thoroughly investigated the influence of constant 2.45 GHz MW irradiation on glucose uptake in yeast cells. A Saccharomyces cerevisiae suspension of 2.9 × 10 cells/ml was used in all experiments. A large specific absorption rate of 0.55 W/g of suspension is compensated by efficient external cooling of the reaction vessel, which established a strong non-equilibrium flow of energy through the solution and enabled a constant bulk temperature of 30 °C to within 1 °C during glucose uptake. Comparison of MW effects with control experiments revealed insignificant changes of glucose uptake during the initial stages of the experiment (up to the 10th min). Statistically 'notable' differences during the next 20 min of the irradiation were detected corresponding to thermal overheating of 2 °C. Possible specific thermal MW effects may be related to local temperature increase and a large flow of energy throughout the system. The obtained effects show that environmental MW pollution (fortunately) is of too low intensity to provoke metabolic changes in living cells. At the same time, a longer exposure of cells to electromagnetic irradiation may have impacts on biochemical applications and production of valuable biotechnological products. [ABSTRACT FROM AUTHOR]

A central composite design combined with response surface methodology was utilized to optimise microwave-assisted extraction of flavonoids from young barley leaves. The results showed that using water as solvent, the optimum conditions of microwave-assisted extraction were extracted twice at 1.27 W g-1 microwave power and liquid-solid ratio 34.02 ml g-1 for 11.12 min. The maximum extraction yield of flavonoids (rutin equivalents) was 80.78±0.52%. Compared with conventional extraction method, the microwave-assisted extraction was more efficient as the extraction time was only 6.18% of conventional extraction, but the extraction yield of flavonoids was increased by 5.47%. The main flavonoid components from the young barley leaf extract were probably 33.36% of isoorientin-7-O-glueoside and 54.17% of isovitexin-7-O-glucoside, based on the HPLC-MS analysis. The barley leaf extract exhibited strong reducing power as well as the DPPH radical scavenging capacity. [ABSTRACT FROM AUTHOR]

A newly designed continuous-flow 915 MHz microwave wastewater treatment system was used to demonstrate the effectiveness of the microwave enhanced advanced oxidation process (MW/H2O2-AOP) for treating dairy manure. After the treatment, about 84% of total phosphorus and 45% of total chemical oxygen demand were solubilized with the highest H2O2dosage (0.4% H2O2per %TS). The reaction kinetics of soluble chemical oxygen demand revealed activation energy to be in the range of 5–22 kJ mole−1. The energy required by the processes was approximately 0.16 kWh per liter of dairy manure heated. A higher H2O2dosage used in the system had a better process performance in terms of solids solubilization, reaction kinetics, and energy consumption. Cost-benefit analysis for a farm-scale MW/H2O2-AOP treatment system was also presented. The results obtained from this study would provide the basic knowledge for designing an effective farm-scale dairy manure treatment system. [ABSTRACT FROM PUBLISHER]

The effect of microwave and heat pretreatment on the content and composition of anthocyanins, phenolics, and the antioxidant capacity of hawthorn drink were studied. Nine anthocyanins were isolated by chromatographic separation from the Zirou hawthorn source and their structure identified using HPLC-DAD-ESI/MS analysis. Heat and microwave pretreatments had a significant impact on the relative contents of hawthorn anthocyanins, such as cyanidin-3-galactoside (82.9% and 76.9%, respectively) and cyanidin-3-glucoside (9.2% and 11.5%, respectively). Pretreatment had no significant effect on pH, total soluble solid or total acid. More anthocyanins remained after heat treatment than after microwaving (0.745 mg/100 mL), and were 52.4% higher than the control group after storage for 7 days. The colour density of the heat treated group was higher than the control group (24.5%) after 12 days of fermentation. The main antioxidant capacities of the hawthorn drinks came from total polyphenolics rather than total anthocyanins or total flavonoids. [ABSTRACT FROM AUTHOR]

Microwave irradiation of tissue during fixation and subsequent histochemical staining procedures significantly reduces the time required for incubation in fixation and staining solutions. Minimizing the incubation time in fixative reduces disruption of tissue morphology, and reducing the incubation time in staining solution or antibody solution decreases nonspecific labeling. Reduction of incubation time in staining solution also decreases the level of background noise. Microwave-assisted tissue preparation is applicable for tissue fixation, decalcification of bone tissues, treatment of adipose tissues, antigen retrieval, and other special staining of tissues. Microwave-assisted tissue fixation and staining are useful tools for histological analyses. This review describes the protocols using microwave irradiation for several essential procedures in histochemical studies, and these techniques are applicable to other protocols for tissue fixation and immunostaining in the field of cell biology. [ABSTRACT FROM AUTHOR]

Microwave radiation (MWR) leads to hazardous effects on he central nervous system (CNS) for both human and animals. The widespread use of mobile phones has increased the risks of health problems in the CNS caused by radiofrequency (RF) electromagnetic fields. To determine these effects various methodological approaches related to neuroscience such as stereology, immunohistochemistry, and electron microscopy have been used. These approaches examine the effects on cells exposed to MWR at the light microscopic and ultrastructural levels, and novel information is obtained. The main aim of this paper is to discuss possible side effects of MWR in the light of current literature with different methodological approaches. [ABSTRACT FROM AUTHOR]

Non-thermal microwave/lower frequency electromagnetic fields (EMFs) act via voltage-gated calcium channel (VGCC) activation. Calcium channel blockers block EMF effects and several types of additional evidence confirm this mechanism. Low intensity microwave EMFs have been proposed to produce neuropsychiatric effects, sometimes called microwave syndrome, and the focus of this review is whether these are indeed well documented and consistent with the known mechanism(s) of action of such EMFs. VGCCs occur in very high densities throughout the nervous system and have near universal roles in release of neurotransmitters and neuroendocrine hormones. Soviet and Western literature shows that much of the impact of non-thermal microwave exposures in experimental animals occurs in the brain and peripheral nervous system, such that nervous system histology and function show diverse and substantial changes. These may be generated through roles of VGCC activation, producing excessive neurotransmitter/neuroendocrine release as well as oxidative/nitrosative stress and other responses. Excessive VGCC activity has been shown from genetic polymorphism studies to have roles in producing neuropsychiatric changes in humans. Two U.S. government reports from the 1970s to 1980s provide evidence for many neuropsychiatric effects of non-thermal microwave EMFs, based on occupational exposure studies. 18 more recent epidemiological studies, provide substantial evidence that microwave EMFs from cell/mobile phone base stations, excessive cell/mobile phone usage and from wireless smart meters can each produce similar patterns of neuropsychiatric effects, with several of these studies showing clear dose–response relationships. Lesser evidence from 6 additional studies suggests that short wave, radio station, occupational and digital TV antenna exposures may produce similar neuropsychiatric effects. Among the more commonly reported changes are sleep disturbance/insomnia, headache, depression/depressive symptoms, fatigue/tiredness, dysesthesia, concentration/attention dysfunction, memory changes, dizziness, irritability, loss of appetite/body weight, restlessness/anxiety, nausea, skin burning/tingling/dermographism and EEG changes. In summary, then, the mechanism of action of microwave EMFs, the role of the VGCCs in the brain, the impact of non-thermal EMFs on the brain, extensive epidemiological studies performed over the past 50 years, and five criteria testing for causality, all collectively show that various non-thermal microwave EMF exposures produce diverse neuropsychiatric effects. [ABSTRACT FROM AUTHOR]

This research is concerned with microwave ablation analyses using a 2.45 GHz four-tine (4T) antenna for hepatic cancer tissue. In the study, three-dimensional finite-element models were utilized to examine the tissue temperature distributions during and after MW ablation. A preliminary study was first carried out with regard to the specific absorption rates along the 4T antenna insertion depths and the temperature distributions inside the solid and porous liver models with either 3 cm-in-diameter tumor or 5 cm-in-diameter tumor. Based on the preliminary results, the porous models were further examined for the effect of varying blood flow velocities (0–200 cm/s) with a 1 cm-in-diameter blood vessel next to the antenna and also for the effect of vessel-antenna locations (0, 0.8, and 1.3 cm) with a constant blood flow velocity of 16.7 cm/s. All scenarios were simulated under temperature-controlled mode (90°C). The findings revealed that the blood flow velocity and vessel location influence the ablation effectiveness and that increased blood flow inhibits heat transfer to the vessel wall. At the nearest and farthest vessel-antenna locations (0 and 1.3 cm), approximately 90.3% and 99.55% of the cancer cells were eradicated except for the areas adjacent to the vessel. In addition, total tissue thermal displacement is 5.9 mm which is 6.59% of the total length of the overall model. [ABSTRACT FROM AUTHOR]

The article discusses microwave hearing effect in telecommunication riggers which is attributed to radiofrequency (RF) radiation. Topics discussed includethe risks of pulsed RF radiation, several key research objectives on whether microwave hearing effect results in distraction of workers during high-risk work at height, and the analysis of results from the questionnaire administered to a target population of telecommunication riggers.

Microwave-assisted method has wide application in combinatorial chemistry. It has become a powerful tool in building the bioactive and pharmaceutical important compounds library within a short time. In view of a pronounced effect of Microwave-assisted methods in synthetic chemistry and their importance in drug discovery, a systematic work on the solvent-free synthesis of 2,4-(IH,3H)Pyrimidinedione(uracil) was carried out. Comparison was made between classic (conventional) and Novel (microwave-assisted) methods and it was found that compounds synthesized by microwave-assisted method showed better yield and reduced reaction time under safe and environment-friendly conditions, while conventional methods were tedious and time consuming. The structure elucidation of synthesized compounds was done by its melting/boiling points, solubility, thin layer chromatography (TLC) techniques and spectral analysis i.e ultraviolet (UV), Fourier transform infrared spectroscopy (FTIR) and Gas chromatography-mass spectrometry (GC-MS) were used to get the results. The pharmacological evaluation of synthesized compound was investigated by its antiviral activities against Lasota strain of NDV (ranikhait disease virus) and it showed the positive activity. [ABSTRACT FROM AUTHOR]

A close association between microwave (MW) radiation exposure and neurobehavioral disorders has been postulated but the direct effects of MWradiation on central nervous system still remains contradictory. This study was performed to understand the effect of short (15 days) and long-term (30 and 60 days) low-levelMWradiation exposure on hippocampus with special reference to spatial learning and memory and its underlying mechanism in Swiss strain male mice, Mus musculus. Twelve-weeks old mice were exposed to 2.45GHz MWradiation (continuous-wave [CW] with overall average power density of 0.0248 mW/cm² and overall average whole body specific absorption rate value of 0.0146 W/Kg) for 2 h/day over a period of 15, 30, and 60 days). Spatial learning and memory was monitored by Morris Water Maze. We have checked the alterations in hippocampal oxidative/nitrosative stress, neuronal morphology, and expression of pro-apoptotic proteins (p53 and Bax), inactive executioner Caspase- (pro-Caspase-3), and uncleaved Poly (ADP-ribose) polymerase-1 in the hippocampal subfield neuronal and nonneuronal cells (DG, CA1, CA2, and CA3). We observed that, short-termas well as long-term2.45GHzMWradiation exposure increases the oxidative/nitrosative stress leading to enhanced apoptosis in hippocampal subfield neuronal and nonneuronal cells. Present findings also suggest that learning and spatial memory deficit which increases with the increased duration ofMWexposure (15<30<60 days) is correlated with a decrease in hippocampal subfield neuronal arborization and dendritic spines. These findings led us to conclude that exposure to CW MWradiation leads to oxidative/nitrosative stress induced p53-dependent/independent activation of hippocampal neuronal and nonneuronal apoptosis associated with spatial memory loss. [ABSTRACT FROM AUTHOR]

Over the past decade people have been constantly exposed to microwave radiation mainly from wireless communication devices used in day to day life. Therefore, the concerns over potential adverse effects of microwave radiation on human health are increasing. Until now no study has been proposed to investigate the underlying causes of genotoxic effects induced by low intensity microwave exposure. Thus, the present study was undertaken to determine the influence of low intensity microwave radiation on oxidative stress, inflammatory response and DNA damage in rat brain. The study was carried out on 24 male Fischer 344 rats, randomly divided into four groups ( n = 6 in each group): group I consisted of sham exposed (control) rats, group II–IV consisted of rats exposed to microwave radiation at frequencies 900, 1800 and 2450 MHz, specific absorption rates (SARs) 0.59, 0.58 and 0.66 mW/kg, respectively in gigahertz transverse electromagnetic (GTEM) cell for 60 days (2 h/day, 5 days/week). Rats were sacrificed and decapitated to isolate hippocampus at the end of the exposure duration. Low intensity microwave exposure resulted in a frequency dependent significant increase in oxidative stress markers viz . malondialdehyde (MDA), protein carbonyl (PCO) and catalase (CAT) in microwave exposed groups in comparison to sham exposed group ( p < 0.05). Whereas, levels of reduced glutathione (GSH) and superoxide dismutase (SOD) were found significantly decreased in microwave exposed groups ( p < 0.05). A significant increase in levels of pro-inflammatory cytokines (IL-2, IL-6, TNF-α, and IFN-γ) was observed in microwave exposed animal ( p < 0.05). Furthermore, significant DNA damage was also observed in microwave exposed groups as compared to their corresponding values in sham exposed group ( p < 0.05). In conclusion, the present study suggests that low intensity microwave radiation induces oxidative stress, inflammatory response and DNA damage in brain by exerting a frequency dependent effect. The study also indicates that increased oxidative stress and inflammatory response might be the factors involved in DNA damage following low intensity microwave exposure. [ABSTRACT FROM AUTHOR]

Hyperthermia is potentially an effective method for the treatment of cancer, especially breast cancer tumors. One of the most attractive attributes of hyperthermia is the possibility of providing therapeutic benefit noninvasively, minimizing side effects. To be effective, a hyperthermia treatment must selectively heat the cancerous tissue, elevating the temperature in the tumor without exposing healthy tissue to excessive temperature elevations. In this paper, a suggested simple model of Annular Phased Array (APA) using eight half wavelength linear dipoles is presented. New software (COMSOL MULTIPHYSICS) is used to calculate the temperature distribution inside a model of a three layered breast (skin, breast tissue, and tumor). In addition, the effect of changing the amplitude and phases of the array elements on the temperature distributions and the conditions on the values of the phases are demonstrated in order to achieve the objective of hyperthermia for breast tumor treatment. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effectiveness of microwave pretreatments on methane production from two switchgrass tissues (leaf vs. stem). The methane production from the leaf fraction was significantly affected by the microwave final temperature, while production from the stem fraction was affected by the combination of the microwave final temperature and heating rate. Thus, the highest methane yield from the leaf (134.81 mL CH4/g of volatile solids (VS)) was obtained at 100 °C, while the highest yield from the stem (99.35 mL CH4/g VS) was obtained at 150 °C, with a heating rate of 10 °C/min. Although methane production from the leaf fraction was merely enhanced by 9.1% after microwave pretreatments, the time required to reach 80% of ultimate methane production was reduced by 12 days. For the stem fraction, methane production was improved by 5.2% after microwave pretreatment, and the time to obtain 80% of ultimate methane production increased. [ABSTRACT FROM AUTHOR]

The effect of mobile phone radiation on human reproduction system is still a matter of debate. In this study, 18 male rabbits were randomly divided into two experimental groups and one control group. Experimental groups received simulated microwaves with the frequency of 950 MHz and the output power of 3 and 6 watts for 2 weeks, 2 h a day. After a week of rest, the microscopic slides from the quada of the excised epididymis were prepared. Then, the diameter of epididymis, the height of epithelium and the number of apoptotic cells in epithelium in study groups were determined. The data were compared using spss software and one-way anova test. The epithelial height and diameter of the epididymis in 3 watt and 6 watt groups had a significant decrease compared to the control group ( P < 0.001), while the testosterone level only in 6 watt group was significantly decreased compared to control group. The rate of apoptosis in the epithelial cells of the epididymis had a significant increase only in 6 watt group compared to the control group ( P < 0.001). This study showed that the microwaves with the frequency of 950 MHz can have negative impacts on morphometric and apoptotic changes of rabbit epididymis. [ABSTRACT FROM AUTHOR]

Purpose: Microwave ablation (MWA) is a new minimally invasive method for thermal ablation of benign thyroid nodules with promising results. The aim of this study was to investigate whether MWA has an impact on thyroid function.Materials and methods: Thirty patients with a total of 34 benign thyroid nodules underwent MWA between January 2013 and July 2014. Serum levels of triiodothyronine (T3), thyroxine (T4), thyrotropin (TSH), thyroglobuline (Tg) and additionally antibodies against Tg (anti-Tg), thyrotropin receptors (TRAb) and thyroid peroxidase (anti-TPO) were measured at enrolment, 24 h after MWA, as well as at the 3-month and 6-month follow-up. Moreover, the nodule volume was evaluated to determine effectiveness.Results: Serum TSH, T4, T3 and Tg levels did not change significantly at the 3-month or 6-month follow-up (p > 0.05); thyroid function was not affected by MWA. Antibody levels did not change significantly either; however, two patients developed antibodies after treatment. A volume reduction of 51.4% or 7.85 mL could be demonstrated after 3 months and a reduction of 55.8% or 14.0 mL after 6 months. Slight complications such as mild pain during the ablation or superficial haematomas emerged. The development of Graves’ disease and mild Horner’s syndrome were observed as more severe side effects.Conclusions: The data suggest MWA as an alternative for the treatment of benign thyroid nodules. While first results for preservation of thyroid function are positive, further measurements of laboratory data and especially antibodies are necessary. [ABSTRACT FROM PUBLISHER]

Purpose: This paper compares the results obtained with numerical simulations andex vivoexperiments involving a dual applicator microwave thermal ablation system operating at a 2.45 GHz frequency, both in synchronous and asynchronous modes. Our purpose was to demonstrate that at this frequency an asynchronous or switched-mode system performs essentially as well as the synchronous one, in spite of the prevailing belief that coherence would assure better thermal (TH) synergy.Numerical analysis: The calculations of temperature fields were based on the Pennes bioheat equation, taking into account the effects of blood perfusion by means of a full-wave 3D simulator that allows numerical electromagnetic (EM) and TH analyses.Materials and methods: Experiments were done using a 100 W microwave (MW) power generator and a fast switched-mode sequential ‘active’ power splitter. By adding a further passive power splitter we arranged a test bed for an accurate experimental comparison of synchronous versus switched-mode TH ablations.Results: The experimental ablation zones produced by a dual applicator array onex vivoswine tissue corresponded well with the simulated ones, confirming that the simplifications assumed in the full-wave analysis were compatible with the aim of our work.Conclusions: Numerical simulations and experiments show that at a 2.45 GHz industrial, scientific and medical (ISM) frequency, synchronous, asynchronous and switched-mode multi-probe systems are substantially equivalent in terms of ablative performance. Moreover, the switched-mode solution offers simpler operation along with lesser sensitivity to the placement of applicators in the tissue. [ABSTRACT FROM PUBLISHER]

Objective To gain a better understanding of gene expression changes in the brain following microwave exposure in mice. This study hopes to reveal mechanisms contributing to microwave-induced learning and memory dysfunction. Methods Mice were exposed to whole body 2100 MHz microwaves with specific absorption rates (SARs) of 0.45 W/kg, 1.8 W/kg, and 3.6 W/kg for 1 hour daily for 8 weeks. Differentially expressing genes in the brains were screened using high-density oligonucleotide arrays, with genes showing more significant differences further confirmed by RT-PCR. Results The gene chip results demonstrated that 41 genes (0.45 W/kg group), 29 genes (1.8 W/kg group), and 219 genes (3.6 W/kg group) were differentially expressed. GO analysis revealed that these differentially expressed genes were primarily involved in metabolic processes, cellular metabolic processes, regulation of biological processes, macromolecular metabolic processes, biosynthetic processes, cellular protein metabolic processes, transport, developmental processes, cellular component organization, etc. KEGG pathway analysis showed that these genes are mainly involved in pathways related to ribosome, Alzheimer's disease, Parkinson's disease, long-term potentiation, Huntington's disease, and Neurotrophin signaling. Construction of a protein interaction network identified several important regulatory genes including synbindin (sbdn), Crystallin (CryaB), PPP1CA, Ywhaq, Psap, Psmb1, Pcbp2, etc., which play important roles in the processes of learning and memory. Conclusion Long-term, low-level microwave exposure may inhibit learning and memory by affecting protein and energy metabolic processes and signaling pathways relating to neurological functions or diseases. [ABSTRACT FROM AUTHOR]

In this study, the effects of microwave drying power on drying kinetics, effective moisture diffusivity, and specific energy consumption of olive pomace were studied at three different microwave power levels of 170, 360 and 510 W. Increasing microwave power resulted in a considerable decrease in drying time. The experimental data for moisture loss was converted to moisture ratios and fitted to eleven thin layer drying mathematical models to describe the drying process. Among the models tested, the Midilli et al. and Diffusion Approach models were found to be the most appropriate in describing microwave drying kinetics of olive pomace. The effective moisture diffusivity values varied from 3.55 x 10-9 to 20.47 x 10-9 m²/s and increased with increase in microwave power. The activation energy was calculated using an exponential expression based on Arrhenius equation and was found to be 20.98 W/g. The specific energy consumption values were in the range of 52.56 to 25.32 MJ/kg [H2O], under applied drying conditions. [ABSTRACT FROM AUTHOR]

More and more saffron has been cultivated in China because of the increasing saffron demand, but no paper has studied the influence of drying methods on the quality of Chinese saffron. In this paper, three different dehydration treatments applied in actual production were evaluated: dehydration with electric oven, vacuum oven, and microwave. We determined that the highest quality of saffron will be obtained when fresh saffron is treated at higher temperatures (no more than 70°C) for a long time by electric oven drying and vacuum oven drying. In microwave drying, treatments at lower microwave power and longer time benefit the quality of saffron. In addition, the influence of the drying method on antioxidants in saffron is discussed. The correlation between individual saffron profiles and the antioxidant value was estimated by spectrum-effect relationships analysis. [ABSTRACT FROM AUTHOR]

Purpose: Combination of percutaneous microwave ablation (PMWA) and intravenous injection of 131I-hypericin(IIIH) may bear potential as a mini-invasive treatment for tumor. The objective of this study was to assess the effect of PMWA and IIIH in breast tumor growth. Methods: Ten New Zealand White rabbits bearing VX2 breast carcinomas were randomly divided into two groups (each 5 examples) and processed using PMWA followed by IIIH and IIIH alone. The IIIH activity was evaluated using planar scintigraphy, autoradiography and biodistribution analysis. The maximum effective safe dose of IIIH was found through 48 rabbits with VX2 breast tumor, which were randomized into six groups (n=8 per group). Subsequently, a further 75 rabbits bearing VX2 breast solid tumors were randomly divided into five groups (each 15 examples) and treated as follows: A, no treatment group; B, PMWA alone; C, IIIH alone; D, PMWA+IIIH×1 (at 8 h post-PMWA); and E, PMWA+IIIH×2 (at 8 h and at 8 days post-PMWA). The therapeutic effect was assessed by measurement of tumor size and performation of positron emission tomography/computed tomograph (PET/CT) scans, liver and renal function tests and Kaplan-Meier survival analysis. Results: The planar scintigraphy findings suggested a significant uptake of 131I in necrotic tumor tissue. The autoradiography gray scales indicated higher selective uptake of IIIH by necrotic tissue, with significant differences between the groups with and those without necrotic tumor tissue (P<0.05). The maximum effective safe dose of IIIH was 1mCi/kg. The PET/CT scans and tumor size measurement suggested improvements in treatment groups at all time points (P<0.01). Significant differences were detected among Groups A, B, D and E (P<0.05). Lower levels of lung metastasis were detected in Groups D and E (P<0.05). There were no abnormalities in liver and renal functions tests or other reported side effects. Conclusion: IIIH exhibited selective uptake by necrotic tumor tissue. Sequential therapy involving PMWA+IIIH was successfully inhibiting tumor growth and prolonging survival. [ABSTRACT FROM AUTHOR]