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Water contamination due to environmental conditions and poor waste management in certain areas of the world represents a serious problem in accessing clean and safe drinking water. This problem is especially critical in electricity-poor regions, where advanced water purification methods are absent. Here, we demonstrate that titanium dioxide nanowires (TiO2NWs)-based photocatalytic filters assisted only with sunlight can efficiently decontaminate water. Moreover, interweaving TiO2NWs with carbon nanotubes (CNTs) leads to the formation of a TiO2NWs/CNTs composite material and offers an additional water decontamination channel, that is of pasteurization with the visible part of the solar emission spectrum. Our results demonstrate that this nanoporous filter can successfully intercept various types of microbial pathogens, including bacteria and large viruses. In addition, photo-catalytically generated reactive oxygen species (ROS) on the surface of the TiO2NWs/CNTs-based filter material under exposure to sunlight contribute to an efficient removal of a broad range of organic compounds and infective microbes. A pilot study also yielded encouraging results in reducing traces of drugs and pesticides in drinking water. [ABSTRACT FROM AUTHOR]

Background: Transcranial Pulse Stimulation (TPS) has been recently introduced as a novel ultrasound neuromodulation therapy with the potential to stimulate the human brain in a focal and targeted manner. Here, we present a first retrospective analysis of TPS as an add-on therapy for Parkinson's disease (PD), focusing on feasibility, safety, and clinical effects. We also discuss the placebo response in non-invasive brain stimulation studies as an important context., Methods: This retrospective clinical data analysis included 20 PD patients who received ten sessions of TPS intervention focused on the individual motor network. Safety evaluations were conducted throughout the intervention period. We analyzed changes in motor symptoms before and after TPS treatment using Unified Parkinson's Disease Rating Scale part III (UPDRS-III)., Results: We found significant improvement in UPDRS-III scores after treatment compared to baseline (pre-TPS: 16.70 ± 8.85, post-TPS: 12.95 ± 8.55; p < 0.001; Cohen's d = 1.38). Adverse events monitoring revealed no major side effects., Conclusion: These preliminary findings suggest that TPS can further improve motor symptoms in PD patients already on optimized standard therapy. Findings have to be evaluated in context with the current literature on placebo effects., (© 2023. The Author(s).)

Air-coupled ultrasound sensors have advantages over contact ultrasound sensors when a sample should not become contaminated or influenced by the couplant or the measurement has to be a fast and automated inline process. Thereby, air-coupled transducers must emit high-energy pulses due to the low air-to-solid power transmission ratios (10 -3 to 10 -8 ). Currently used resonant transducers trade bandwidth-a prerequisite for material parameter analysis-against pulse energy. Here we show that a combination of a non-resonant ultrasound emitter and a non-resonant detector enables the generation and detection of pulses that are both high in amplitude (130 dB) and bandwidth (2 µs pulse width). We further show an initial application: the detection of reflections inside of a carbon fiber reinforced plastic plate with thicknesses between 1.7 mm and 10 mm. As the sensors work contact-free, the time of flight and the period of the in-plate reflections are independent parameters. Hence, a variation of ultrasound velocity is distinguishable from a variation of plate thickness and both properties are determined simultaneously. The sensor combination is likely to find numerous industrial applications necessitating high automation capacity and opens possibilities for air-coupled, single-side ultrasonic inspection.

Transcranial ultrasound holds much potential as a safe, non-invasive modality for navigated neuromodulation, with low-intensity focused ultrasound (FUS) and transcranial pulse stimulation (TPS) representing the two main modalities. While neuroscientific and preclinical applications have received much interest, clinical applications are still relatively scarce. For safety considerations, the current literature is largely based on guidelines for ultrasound imaging that uses various physical parameters to describe the ultrasound pulse form and expected bioeffects. However, the safety situation for neuromodulation is inherently different. This article provides an overview of relevant ultrasound parameters with a focus on bioeffects relevant for safe clinical applications. Further, a retrospective analysis of safety data for clinical TPS applications in patients is presented.

High sensitivity is an important requirement for air-coupled ultrasonic sensors applied to materials testing. With a lower acoustic impedance than any piezoelectric material, charged cellular polypropylene (PP) offers better matching to air with a similar piezoelectric coefficient. The piezoelectric properties of charged cellular PP originate from their polarization, creating permanent internal voltage. The sensitivity of the sensor can be increased by applying additional dc bias voltage, as it has been done already for transmitters. This work presents the first ultrasonic sensor based on charged cellular PP including a high-voltage module providing dc bias voltage up to 2 kV. This bias voltage led to an increase in the signal-to-noise ratio of up to 15 ± 1 dB. The measurement of the received signal depending on the applied bias voltage is proposed as a new method of determining the internal voltage of ferroelectrets. The sensor combined with a cellular PP transmitter was applied to nondestructive testing of a rotor blade segment and glued-laminated timber, enabling imaging of the internal structure of these specimens with a thickness around 4 cm.

The human androgen receptor (AR) is a ligand inducible transcription factor that harbors an amino terminal domain (AR-NTD) with a ligand-independent activation function. AR-NTD is intrinsically disordered and displays aggregation properties conferred by the presence of a poly-glutamine (polyQ) sequence. The length of the polyQ sequence as well as its adjacent sequence motifs modulate this aggregation property. AR-NTD also contains a conserved KELCKAVSVSM sequence motif that displays an intrinsic property to form amyloid fibrils under mild oxidative conditions. As peptide sequences with intrinsic oligomerization properties are reported to have an impact on the aggregation of polyQ tracts, we determined the effect of the KELCKAVSVSM on the polyQ stretch in the context of the AR-NTD using atomic force microscopy (AFM). Here, we present evidence for a crosstalk between the amyloidogenic properties of the KELCKAVSVSM motif and the polyQ stretch at the AR-NTD., Competing Interests: The authors declare no conflict of interest. The funding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

Optison(R) is an ultrasound contrast agent, consisting of gas-filled microspheres surrounded by a solid shell of heat-denatured human albumin. Size-distribution measurements of these microspheres are a critical stability indicating factor, because loss of encapsulated gas eliminates ultrasound contrast activity. Composition of the encapsulated gas is also critical, because air-filled microspheres do not persist nearly as long in vivo as microspheres filled with less soluble gases. Optison(R) stability has been tested during exposure to chemical substances expected to dissolve microsphere shells. In addition, size-distribution and gas-composition measurements were used to evaluate the effects of external gas composition, elevated temperature, mixing, needle shear and pressure on product stability. Optison(R) microsphere shells dissolve only when exposed to relatively extreme chemical conditions, such as low pH (<4.0), detergents or chaotropic salts. The shells are highly gas-permeable, and microspheres lose encapsulated gas rapidly and irreversibly when exposed to gas-deficient liquids. Pressure, impact stress, and the application of ultrasound energy all cause liquids to become gas-deficient, and also cause irreversible gas loss. Pressure sensitivity differs dramatically between mixed and unmixed microspheres, further supporting the conclusion that gas diffusion is the major cause of Optison(R) instability. To preserve the efficacy of Optison(R) as an ultrasound contrast agent, it is necessary to devote special attention to minimizing opportunities for gas exchange, mixing and exposure to gas-deficient liquids, so that the size distribution and gas composition of the original product are maintained during handling.