Dioxygen Activation by Copper-Bleomycin: Theoretical Considerations

Density functional theory (DFT) calculations are employed to calculate probable reaction intermediates in dioxygen activation by bleomycin-ligated copper – Cu(I)-dioxygen, Cu(I)-superoxo and Cu(II)-hydroperoxo. The electronic structures of these intermediates are discussed with emphasis on their electromerism. Importantly, unlike in dioxygen activation by iron-bleomycin, formation of these reactive intermediates requires that some of the copper-bleomycin bonds be broken. (doi: 10.5562/cca1793

Music Assisted Progressive Muscle Relaxation and Virtual Reality Exposure Therapy for Specific Phobia: Two Case Studies

Specific phobia is a prevalent psychiatric disorder characterized by an irrational fear disproportionate to the threat that the object or situation poses. This anxiety disorder profoundly impacts individuals, affecting their personal, social, and occupational spheres. This study aimed to explore the use of Music Assisted Progressive Muscle Relaxation (M+PMR) and Virtual Reality Exposure Therapy (VRET) in the treatment of specific phobia.Music therapy techniques, such as M+PMR, have shown potential in optimizing therapeutic outcomes when treating specific phobia or prior to exposure therapy. These techniques involve utilizing music elements like slow tempo, major mode, simple rhythms, and calming instrumental timbres. Additionally, VRET is a type of exposure therapy that provides a safe and controlled environment for confronting phobias. Being mentally present and physiologically aware during VRET sessions is essential for successful therapy, as high arousal during VRET eventually leads to symptom reduction and decreased avoidance behaviors. By exploring the utilization of M+PMR and VRET to treat specific phobias, we can further investigate their effectiveness.In this study, the participants, Andrew and Natalie, experienced a state of relaxation during the M+PMR sessions. The incorporation of music and progressive muscle relaxation seemed to enhance their awareness of physiological responses, leading to a heightened attentiveness to bodily sensations during the intervention. The use of soothing piano music, slow tempo, and soft tones complemented the PMR script, facilitating a state of relaxation and presence.Moreover, both Andrew and Natalie expressed a sense of being present in the moment during the M+PMR sessions. Furthermore, the results indicated that both participants felt prepared for exposure therapy following the M+PMR sessions. The relaxation and calmness induced by M+PMR seemed to contribute to their readiness to confront their phobic triggers in the virtual environment

Variable Power, Short Microwave Pulses Generation using a CW Magnetron

Fine control of microwave power radiation in medical and scientific applications is a challenging task. Since a commercial Continuous Wave (CW) magnetron is the most inexpensive microwave device available today on the market, it becomes the best candidate for a microwave power generator used in medical diathermy and hyperthermia treatments or high efficiency chemical reactions using microwave reactors as well. This article presents a new method for driving a CW magnetron with short pulses, using a modified commercial Zero Voltage Switching (ZVS) inverter, software driven by a custom embedded system. The microwave power generator designed with this method can be programmed for output microwave pulses down to 1% of the magnetron's power and allows microwave low frequency pulse modulation in the range of human brain electrical activity, intended for medical applications. Microwave output power continuous control is also possible with the magnetron running in the oscillating area, using a dual frequency Pulse Width Modulation (PWM), where the low frequency PWM pulse is modulating a higher resonant frequency required by the ZVS inverter's transformer. The method presented allows a continuous control of both power and energy (duty-cycle) at the inverter's output

Microwave heating device

The invention relates to a microwave heating device (1) comprising: - a microwave generator (2) for generating a microwave radiation to a microwave input (4), - at least four slots (41) arranged in a first plane (P1), the microwave input (4) being connected to the cavity (10) through the feeding slots (41) so that the microwave radiation is fed into the cavity (10) through the feeding slots (41), and - a first multi-slot resonator (5) arranged between the feeding slots (41) and the load (15) and extending in a second plane (P2) parallel to the first plane (P1), the first multi-slot resonator (5) being provided with multiple primary homogenization slots (51) arranged to divide the microwave radiation fed into the cavity (10)

Microwave heating device

The invention relates to a microwave heating device (1) comprising: - a microwave generator (2) for generating a microwave radiation to a microwave input (4), - at least four slots (41) arranged in a first plane (P1), the microwave input (4) being connected to the cavity (10) through the feeding slots (41) so that the microwave radiation is fed into the cavity (10) through the feeding slots (41), and - a first multi-slot resonator (5) arranged between the feeding slots (41) and the load (15) and extending in a second plane (P2) parallel to the first plane (P1), the first multi-slot resonator (5) being provided with multiple primary homogenization slots (51) arranged to divide the microwave radiation fed into the cavity (10)

Dielectric properties measurement method in the microwave frequencies range for non-polar/polar liquid mixtures characterization

International audienceWe present a method based on dielectric properties measurements over a large spectrum of frequencies, in themicrowave (MW) domain, in order to characterize a liquid mixture. The liquid mixtures consist of non-polar fluids(silicone oil, diesel fuel) and polar additives, in order to increase the specific MW absorption of the mixture for furtherMW power processing. We have measured the MW specific absorptions for mixtures of silicone oil with 20% and 30%(w/w) isopropanol. In both cases, the mixtures are sufficiently stable over time to allow further studies of thermalconvection dynamics initiated by MW heating. For a mixture of diesel fuel with 10% (w/w) alkyl polyglycoside, the mainobservation was that its MW specific absorption varies over time after the mechanical mixing process

Microwave heating device for internal heating convection experiments, applied to Earth's mantle dynamics

International audienceWe report the design, construction, and performances of a microwave (MW) heating device for laboratory experiments with non-contact, homogeneous internal heating. The device generates MW radiation at 2.47 GHz from a commercial magnetron supplied by a pulsed current inverter using proprietary, feedback based command and control hardware and software. Specially designed MW launchers direct the MW radiation into the sample through a MW homogenizer, devised to even the MW power distribution into the sample's volume. An adjustable MW circuit adapts the MW generator to the load (i.e., the sample) placed in the experiment chamber. Dedicated heatsinks maintain the MW circuits at constant temperature throughout the experiment. Openings for laser scanning for image acquisition with a CCD camera and for the cooling circuits are protected by special MW filters. The performances of the device are analyzed in terms of heating uniformity, long term output power stability, and load matching. The device is used for small scale experiments simulating Earth's mantle convection. The 30 × 30 × 5 cm3 convection tank is filled with a water-based viscous fluid. A uniform and constant temperature is maintained at the upper boundary by an aluminum heat exchanger and adiabatic conditions apply at the tank base. We characterize the geometry of the convective regime as well as its bulk thermal evolution by measuring the velocity field by Particle Image Velocimetry and the temperature field by using Thermochromic Liquid Crystals

Microwaves heating in a specific experimental configuration

International audienc