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Molecules (Basel, Switzerland) Jun 2024This research aimed to encapsulate the fruit extract to increase its stability for incorporation into food products such as jelly or jelly powder. After extraction, the...
This research aimed to encapsulate the fruit extract to increase its stability for incorporation into food products such as jelly or jelly powder. After extraction, the nanoliposomes containing the extract were prepared in ratios of 60-0, 50-10, 40-20, and 30-30 lecithin-to-cholesterol. The effects of lecithin-to-cholesterol concentrations on the related parameters were then evaluated. The results showed that the average particle size was in the range of 95.05 to 164.25 nm, and with an increasing cholesterol concentration, the particle size of the nanoliposomes increased. The addition of cholesterol increased the zeta potential from -60.40 to -68.55 millivolt. Furthermore, cholesterol led to an increase in encapsulation efficiency, and even improved the stability of phenolic compounds loaded in nanoliposomes during storage time. Fourier transform infrared (FTIR) spectroscopy confirmed the successful loading of the extract. Field emission scanning electron microscopy (FE-SEM) analysis revealed nano-sized spherical and almost-elliptical liposomes. For jelly powders, the water solubility index ranged from 39.5 to 43.7% ( > 0.05), and the hygroscopicity values ranged between 1.22 and 9.36 g/100 g ( < 0.05). In conclusion, nanoencapsulated extract displayed improved stability and can be used in jelly preparation without any challenge or unfavorable perception.
Topics: Liposomes; Plant Extracts; Capparis; Particle Size; Nanoparticles; Lecithins; Cholesterol; Drug Compounding; Spectroscopy, Fourier Transform Infrared; Solubility
PubMed: 38930869
DOI: 10.3390/molecules29122804 -
Pacing and Clinical Electrophysiology :... Jun 2024Electromagnetic interference (EMI) encompasses electromagnetic field signals that can be detected by a device's circuitry, potentially resulting in adverse effects such...
BACKGROUND
Electromagnetic interference (EMI) encompasses electromagnetic field signals that can be detected by a device's circuitry, potentially resulting in adverse effects such as inaccurate sensing, pacing, device mode switching, and defibrillation. EMI may impact the functioning of Cardiac Implantable Electronic Devices (CIEDs) and lead to inappropriate therapy.
METHOD
An experimental measuring device, a loop antenna mimicking the implantable cardioverted defibrillator (ICD) antenna, was developed, and validated at the US Food and Drug Administration (FDA) and sent to Wright State University for testing. Two sets of measurements were conducted while the vehicle was connected to a 220-Volt outlet with charging at ON and OFF. Each measurement set involved three readings at various locations, with the antenna oriented in three different positions to account for diverse patient postures. The experiment utilized a Tesla Model 3 electric vehicle (EV), assessing scenarios both inside and outside the car, including the driver's seat, driver's seat floor, passenger's seat, rear seat, rear seat floor, cup holder, charging port (car), and near the charging station.
RESULTS
The detected voltage (max 400 to 504 millivolts) around the cup holder inside the car differed from all other measurement scenarios.
CONCLUSION
The investigation highlights the identification of EMI signals originating from an EV) that could potentially interrupt the functionality of a Subcutaneous Implantable Cardioverter-Defibrillator (S-ICD). These signals fell within the R-wave Spectrum of 30-300 Hz. Further in-vivo studies are essential to determine accurately the level of interference between S-ICDs and EMI from Electric Vehicles.
PubMed: 38830796
DOI: 10.1111/pace.15019 -
Science (New York, N.Y.) May 2024The efficiency and longevity of metal-halide perovskite solar cells are typically dictated by nonradiative defect-mediated charge recombination. In this work, we...
The efficiency and longevity of metal-halide perovskite solar cells are typically dictated by nonradiative defect-mediated charge recombination. In this work, we demonstrate a vapor-based amino-silane passivation that reduces photovoltage deficits to around 100 millivolts (>90% of the thermodynamic limit) in perovskite solar cells of bandgaps between 1.6 and 1.8 electron volts, which is crucial for tandem applications. A primary-, secondary-, or tertiary-amino-silane alone negatively or barely affected perovskite crystallinity and charge transport, but amino-silanes that incorporate primary and secondary amines yield up to a 60-fold increase in photoluminescence quantum yield and preserve long-range conduction. Amino-silane-treated devices retained 95% power conversion efficiency for more than 1500 hours under full-spectrum sunlight at 85°C and open-circuit conditions in ambient air with a relative humidity of 50 to 60%.
PubMed: 38753792
DOI: 10.1126/science.ado2302 -
Advanced Materials (Deerfield Beach,... May 2024Integration of molecular switching units into complex electronic circuits is considered to be the next step towards the realization of novel logic and memory devices....
Integration of molecular switching units into complex electronic circuits is considered to be the next step towards the realization of novel logic and memory devices. Here, we report on an ordered 2D network of neighboring ternary switching units represented by triazatruxene (TAT) molecules organized in a honeycomb lattice on a Ag(111) surface. Using low-temperature scanning tunneling microscopy, we are able to control the bonding configurations of individual TAT molecules within the lattice, realizing up to 12 distinct states per molecule. The switching between those states shows a particularly strong bias dependence ranging from tens of millivolts to volts. Based on a single TAT molecule as a fundamental building block, we then explore the low-bias switching behavior in units consisting of two and more interacting TAT molecules purposefully defined by the high-bias switching within the honeycomb lattice. we demonstrate the possibility to realize up to 9 and 19 distinguishable states in a dyad and a tetrad of coupled switching units, respectively. The switching dynamics can be triggered and accessed by single-point measurements on a single molecule. High experimental control over the desired state, owing to hierarchical switching and pronounced switching directionality, as well as the observed full reversibility, makes this system particularly appealing, paving the way to design complex molecule-based memory systems. This article is protected by copyright. All rights reserved.
PubMed: 38749066
DOI: 10.1002/adma.202401662 -
Nano Letters May 2024Ion transport through nanoporous two-dimensional (2D) membranes is predicted to be tunable by controlling the charging status of the membranes' planar surfaces, the...
Ion transport through nanoporous two-dimensional (2D) membranes is predicted to be tunable by controlling the charging status of the membranes' planar surfaces, the behavior of which though remains to be assessed experimentally. Here we investigate ion transport through intrinsically porous membranes made of 2D metal-organic-framework layers. In the presence of certain cations, we observe a linear-to-nonlinear transition of the ionic current in response to the applied electric field, the behavior of which is analogous to the cation gating effect in the biological ion channels. Specifically, the ionic currents saturate at transmembrane voltages exceeding a few hundreds of millivolts, depending on the concentration of the gating cations. This is attributed to the binding of cations at the membranes' surfaces, tuning the charging states there and affecting the entry/exit process of translocating ions. Our work also provides 2D membranes as candidates for building nanofluidic devices with tunable transport properties.
PubMed: 38747343
DOI: 10.1021/acs.nanolett.4c00991 -
ACS Nano May 2024The subnanometer distance between tip and sample in a scanning tunneling microscope (STM) enables the application of very large electric fields with a strength as high...
The subnanometer distance between tip and sample in a scanning tunneling microscope (STM) enables the application of very large electric fields with a strength as high as ∼1 GV/m. This has allowed for efficient electrical driving of Rabi oscillations of a single spin on a surface at a moderate radiofrequency (RF) voltage on the order of tens of millivolts. Here, we demonstrate the creation of dressed states of a single electron spin localized in the STM tunnel junction by using resonant RF driving voltages. The read-out of these dressed states was achieved all electrically by a weakly coupled probe spin. Our work highlights the strength of the atomic-scale geometry inherent to the STM that facilitates the creation and control of dressed states, which are promising for the design of atomic scale quantum devices using individual spins on surfaces.
PubMed: 38698541
DOI: 10.1021/acsnano.4c00196 -
Nature Materials Apr 2024Electrode arrays that interface with peripheral nerves are used in the diagnosis and treatment of neurological disorders; however, they require complex placement...
Electrode arrays that interface with peripheral nerves are used in the diagnosis and treatment of neurological disorders; however, they require complex placement surgeries that carry a high risk of nerve injury. Here we leverage recent advances in soft robotic actuators and flexible electronics to develop highly conformable nerve cuffs that combine electrochemically driven conducting-polymer-based soft actuators with low-impedance microelectrodes. Driven with applied voltages as small as a few hundreds of millivolts, these cuffs allow active grasping or wrapping around delicate nerves. We validate this technology using in vivo rat models, showing that the cuffs form and maintain a self-closing and reliable bioelectronic interface with the sciatic nerve of rats without the use of surgical sutures or glues. This seamless integration of soft electrochemical actuators with neurotechnology offers a path towards minimally invasive intraoperative monitoring of nerve activity and high-quality bioelectronic interfaces.
PubMed: 38671159
DOI: 10.1038/s41563-024-01886-0 -
Sensors (Basel, Switzerland) Mar 2024The seafloor E-field signal is extremely weak and difficult to measured, even with a high signal-to-noise ratio. The preamplifier for electrodes is a key technology for...
The seafloor E-field signal is extremely weak and difficult to measured, even with a high signal-to-noise ratio. The preamplifier for electrodes is a key technology for ocean-bottom electromagnetic receivers. In this study, a chopper amplifier was proposed and developed to measure the seafloor E-field signal in the nanovolt to millivolt range at significantly low frequencies. It included a modulator, transformer, AC amplifier, high-impedance (hi-Z) module, demodulator, low-pass filter, and chopper clock generator. The injected charge in complementary metal-oxide semiconductor (CMOS) switches that form the modulator is the main source of 1/ noise. Combined with the principles of peak filtering and dead bands, a hi-Z module was designed to effectively reduce low-frequency noise. The chopper amplifier achieved an ultralow voltage noise of 0.6 nV/rt (Hz) at 1 Hz and 1.2 nV/rt (Hz) at 0.001 Hz. The corner frequency was less than 100 mHz, and there were few 1/ noises in the effective observation frequency band used for detecting electric fields. Each component is described with relevant tradeoffs that realize low noise in the low-frequency range. The amplifier was compact, measuring Ø 68 mm × H 12 mm, and had a low power consumption of approximately 23 mW (two channels). The fixed gain was 1500 with an input voltage range of 2.7 mV. The chopper amplifiers demonstrated stable performance in offshore geophysical prospecting applications.
PubMed: 38544183
DOI: 10.3390/s24061920 -
Nature Communications Feb 2024The need for ever-faster information processing requires exceptionally small devices that operate at frequencies approaching the terahertz and petahertz regimes. For the...
The need for ever-faster information processing requires exceptionally small devices that operate at frequencies approaching the terahertz and petahertz regimes. For the diagnostics of such devices, researchers need a spatiotemporal tool that surpasses the device under test in speed and spatial resolution. Consequently, such a tool cannot be provided by electronics itself. Here we show how ultrafast electron beam probe with terahertz-compressed electron pulses can directly sense local electro-magnetic fields in electronic devices with femtosecond, micrometre and millivolt resolution under normal operation conditions. We analyse the dynamical response of a coplanar waveguide circuit and reveal the impulse response, signal reflections, attenuation and waveguide dispersion directly in the time domain. The demonstrated measurement bandwidth reaches 10 THz and the sensitivity to electric potentials is tens of millivolts or -20 dBm. Femtosecond time resolution and the capability to directly integrate our technique into existing electron-beam inspection devices in semiconductor industry makes our femtosecond electron beam probe a promising tool for research and development of next-generation electronics at unprecedented speed and size.
PubMed: 38409203
DOI: 10.1038/s41467-024-45744-8 -
Chaos (Woodbury, N.Y.) Feb 2024Real neurons connect to each other non-randomly. These connectivity graphs can potentially impact the ability of networks to synchronize, along with the dynamics of...
Real neurons connect to each other non-randomly. These connectivity graphs can potentially impact the ability of networks to synchronize, along with the dynamics of neurons and the dynamics of their connections. How the connectivity of networks of conductance-based neuron models like the classical Hodgkin-Huxley model or the Morris-Lecar model impacts synchronizability remains unknown. One powerful tool to resolve the synchronizability of these networks is the master stability function (MSF). Here, we apply and extend the MSF approach to networks of Morris-Lecar neurons with conductance-based coupling to determine under which parameters and for which graphs the synchronous solutions are stable. We consider connectivity graphs with a constant non-zero row sum, where the MSF approach can be readily extended to conductance-based synapses rather than the more well-studied diffusive connectivity case, which primarily applies to gap junction connectivity. In this formulation, the synchronous solution is a single, self-coupled, or "autaptic" neuron. We find that the primary determining parameter for the stability of the synchronous solution is, unsurprisingly, the reversal potential, as it largely dictates the excitatory/inhibitory potential of a synaptic connection. However, the change between "excitatory" and "inhibitory" synapses is rapid, with only a few millivolts separating stability and instability of the synchronous state for most graphs. We also find that for specific coupling strengths (as measured by the global synaptic conductance), islands of synchronizability in the MSF can emerge for inhibitory connectivity. We verified the stability of these islands by direct simulation of pairs of neurons coupled with eigenvalues in the matching spectrum.
Topics: Models, Neurological; Neurons; Synaptic Transmission; Computer Simulation; Synapses; Action Potentials; Nerve Net
PubMed: 38377288
DOI: 10.1063/5.0176956