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Biological neurons are electro-mechanical systems, where the generation and propagation of an action potential are coupled to the generation and transmission of an acoustic wave. Neuristors, such as VO2, characterized by insulator-metal transition (IMT) and negative differential resistance, can be engineered as self-oscillators, which are good approximations of biological neurons in the domain of electrical signals. In this study, we show that these self-oscillators are coupled electro-opto-mechanical systems, with better energy conversion coefficients than the conventional electro-mechanical or electro-optical materials. This is due to the significant contrast in the material's resistance, optical refractive index, and density across the induced temperature range in a Joule heating driven IMT. We carried out laser interferometry to measure the opto-mechanical response while simultaneously driving the devices electrically into self-oscillations of different kinds. We analyzed films of various thicknesses, engineered device geometry, and performed analytical modeling to decouple the effects of refractive index change vis-à-vis mechanical strain in the interferometry signal. We show that the effective piezoelectric coefficient (d13*) for our neuristor devices is 660 ± 20 pm/V, with a 31% internal energy conversion efficiency, making them viable alternatives to Pb-based piezoelectrics for MEMS applications. Furthermore, we show that the effective electro-optic coefficient (r13*) is ∼22 nm/V, which is much larger than that in thin-film and bulk Pockels materials. [ABSTRACT FROM AUTHOR]

This study illustrates how the microstructure of garnet solid‐state electrolytes (SSE) affects the stress‐state and dendrite growth. Tantalum‐doped lithium lanthanum zirconium oxide (LLZTO, Li6.4La3Zr1.4Ta0.6O12) is synthesized by powder processing and sintering (AS), or with the incorporation of intermediate‐stage high‐energy milling (M). The M compact displays higher density (91.5% vs 82.5% of theoretical), and per quantitative stereology, lower average grain size (5.4 ± 2.6 vs 21.3 ± 11.1 µm) and lower AFM‐derived RMS surface roughness contacting the Li metal (45 vs 161 nm). These differences enable symmetric M cells to electrochemically cycle at constant capacity (0.1 mAh cm−2) with enhanced critical current density (CCD) of 1.4 versus 0.3 mA cm−2. It is demonstrated that LLZTO grain size distribution and internal porosity critically affect electrical short‐circuit failure, indicating the importance of electronic properties. Lithium dendrites propagate intergranularly through regions where LLZTO grains are smaller than the bulk average (7.4 ± 3.8 µm for AS in a symmetric cell, 3.1 ± 1.4 µm for M in a half‐cell). Metal also accumulates in the otherwise empty pores of the sintered compact present along the dendrite path. Mechanistic modeling indicates that reaction and stress heterogeneities are interrelated, leading to current focusing and preferential plating at grain boundaries. [ABSTRACT FROM AUTHOR]

Red blood cells (RBCs) are the most abundant cell types in the circulatory system of vertebrates. In fish, RBCs retain their nuclei throughout their lifetime and remain transcriptionally and translationally active. While their primary function is typically associated with gas exchange, recent reports indicate that nucleated red blood cells can play a significant role in regulating the body's innate immune response. The current article describes the innate immune role of red blood cells in rohu (Labeo rohita), a freshwater fish species that holds significant commercial importance in India and South‐East Asian nations. From the whole blood and mucosal surface RBCs have been isolated through density gradient centrifugation with HiSep™LSM 1077 (density 1.007 ± 0.0010) and their purity has been confirmed by the Giemsa staining followed by microscopical observations. Toll‐like receptors (TLR2, 3, 4, 5) and nucleotide oligomerization domain (NOD)‐like receptors (NOD1 and NOD2) in RBCs of rohu fingerlings were observed to be significantly activated (P < 0.05) on infection with Aeromonas hydrophila and Edwardsiella tarda. This activation resulted in increased expression of interleukins (IL‐8, IL‐1β) and interferon (IFN)‐I genes. The activation of TLR4, NOD1 and NOD2, as well as the expression of interleukins and IFN‐I genes have been observed in both in vivo and in vitro stimulation of rohu RBCs with lipopolysaccharides. These findings highlight the importance of fish RBCs in enhancing innate immunity against various pathogenic invasions in rohu. [ABSTRACT FROM AUTHOR]

Atomically-abrupt interfaces in transition metal oxide (TMO) heterostructures could host a variety of exotic condensed matter phases that may not be found in the bulk materials at equilibrium. A critical step in the development of such atomically-sharp interfaces is the deposition of atomically-smooth TMO thin films. Optimized deposition conditions exist for the growth of perovskite oxides. However, the deposition of rutile oxides, such as VO 2 , with atomic-layer precision has been challenging. In this work, we used pulsed laser deposition to grow atomically-smooth VO 2 thin films on rutile TiO 2 (101) substrates. We show that an optimal substrate preparation procedure followed by the deposition of VO 2 films at a temperature conducive for step-flow growth mode is essential for achieving atomically-smooth VO 2 films. The films deposited at optimal substrate temperatures show a step and terrace structure of the underlying TiO 2 substrate. At lower deposition temperatures, there is a transition to a mixed growth mode comprised of island growth and layer-by-layer growth modes. VO 2 films deposited at optimal substrate temperatures undergo a sharp metal to insulator transition, similar to that observed in bulk VO 2 , but at a transition temperature of ∼ 325 K with ∼ 10 3 times increase in resistance. [ABSTRACT FROM AUTHOR]

Astragalus used mainly in Chinese traditional medicine, and in some parts of other Asian countries like Japan. It is one of the fundamental herbs found among medicinal and food plants. The plant contains various beneficial compounds, which provide enormous benefits to human health, such as the improvisation of the immune system, and it prevents and helps in the treatments of many diseases. These compounds act against various diseases like cancer, heart disease, a neurodegenerative disorder, and kidney and urinary-related problems. These elements also perform some crucial activities like anti-microbial activity, anti-oxidative activity, anti-hypertensive effect, etc., which is the precursor for the cause of various diseases. The dried root or the root powder of the plant is widely used as a nutrient supplement and used in foodstuffs includes ice cream, jelly, mayonnaise, syrups, sauce, candies, etc. The bark, root, flower, and stem extracts used widely in cosmetics, such as skin protection and skin whitening. Astragalus membranaceus (AM) is a natural substitute for food, medicine, and cosmetic ingredients as it is always good to replace synthetic ones with natural compounds. Therefore, this review describes the importance of its biologically active molecules and their applications in different health benefits in various aspects. [ABSTRACT FROM AUTHOR]

Background: Preeclampsia poses a substantial clinical challenge, characterized by maternal hypertension, cardiac dysfunction, and persistent cardiovascular risks for both the mother and offspring. Despite the known roles of the estrogen receptor (GPER [G protein-coupled estrogen receptor]) in placental development, its impact on cardiovascular aspects within a preeclampsia animal model remains unexplored. We propose that G-1, a GPER agonist, could have the potential to regulate not only hypertension but also cardiac dysfunction in rats with preeclampsia., Methods: To explore the influence of G-1 on preeclampsia, we used the reduced uterine perfusion pressure (RUPP) model. RUPP rats were administered either G-1 (100 µg/kg per day) or hydralazine (25 mg/kg per day). We conducted echocardiography to probe the intricate cardiac effects of G-1., Results: The RUPP rat model revealed signs of hypertension and cardiac dysfunction and alterations in gene and protein expression within placental and heart tissues. G-1 treatment reduced blood pressure and reversed cardiac dysfunction in rats with preeclampsia. In contrast, administration of the vasodilator hydralazine reduced blood pressure without an improvement in cardiac function. In addition, while G-1 treatment restored the levels of sFLT-1 (soluble fms-like tyrosine kinase-1) in RUPP rats, hydralazine did not normalize this antiangiogenic factor., Conclusions: The therapeutic intervention of G-1 significantly mitigated the cardiovascular dysfunction observed in the RUPP rat model of preeclampsia. This discovery underscores the broader significance of understanding GPER's role in the context of preeclampsia-related cardiovascular complications., Competing Interests: None.

Augmented reality (AR) navigation refers to novel technologies that superimpose images, such as radiographs and navigation pathways, onto a view of the operative field. The development of AR navigation has focused on improving the safety and efficacy of neurosurgical and orthopedic procedures. In this review, the authors focus on 3 types of AR technology used in spine surgery: AR surgical navigation, microscope-mediated heads-up display, and AR head-mounted displays. Microscope AR and head-mounted displays offer the advantage of reducing attention shift and line-of-sight interruptions inherent in traditional navigation systems. With the U.S. Food and Drug Administration's recent clearance of the XVision AR system (Augmedics, Arlington Heights, IL), the adoption and refinement of AR technology by spine surgeons will only accelerate., Competing Interests: Declaration of Conflicting Interests: The author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: Timothy F. Witham, MD, is a medical advisory board member, owns stock or stock options, and receives consultancy fees from Augmedics, the manufacturer of a device discussed in this article. Nicholas Theodore, MD, reports relationships with Neurosurgery Research & Education Foundation (NREF), Defense Advanced Research Projects Agency (DARPA), Globus Medical, Depuy Synthes, and Stryker; and holds patents and receives personal fees for legal case reviews. The other authors declared no potential conflicts of interest., (© The Author(s) 2021.)

Standard diagnostic ultrasound imaging procedures heavily rely on the human operator for image acquisition. This may lead to unnecessary artifacts in the images, since involuntary hand movement is unavoidable. Certain surgical procedures also involve "jump" movement of the subject on the operating table, further exacerbating image quality. In this study, we attempt to mitigate the problem by designing an ultrasound probe holder using 3D printing. This holder would potentially be light enough to attach to surgical retractors, thus eliminating operator intervention and relative motion between the probe and the patient.

Cotton balls are a versatile and efficient tool commonly used in neurosurgical procedures to absorb fluids and manipulate delicate tissues. However, the use of cotton balls is accompanied by the risk of accidental retention in the brain after surgery. Retained cotton balls can lead to dangerous immune responses and potential complications, such as adhesions and textilomas. In a previous study, we showed that ultrasound can be safely used to detect cotton balls in the operating area due to the distinct acoustic properties of cotton compared with the acoustic properties of surrounding tissue. In this study, we enhance the experimental setup using a 3D-printed custom depth box and a Butterfly IQ handheld ultrasound probe. Cotton balls were placed in variety of positions to evaluate size and depth detectability limits. Recorded images were then analyzed using a novel algorithm that implements recently released YOLOv4, a state-of-the-art, real-time object recognition system. As per the radiologists' opinion, the algorithm was able to detect the cotton ball correctly 61% of the time, at approximately 32 FPS. The algorithm could accurately detect cotton balls up to 5mm in diameter, which corresponds to the size of surgical balls used by neurosurgeons, making the algorithm a promising candidate for regular intraoperative use.

Patient safety and efficiency are top priorities in any surgical procedure. One effective way to achieve these objectives is to automate the logistical and routine tasks that occur in the operating suite. Inspired by smart assistant technology already widely used in the consumer sector, we engineered the Smart Hospital Assistant (SHA), a smart, voice-controlled virtual assistant that handles natural speech recognition while executing non-surgical functions to aid any surgery. In simulated procedures, the SHA reduced operating time, optimized surgical staff resources, and reduced the number of major touch-points that can lead to surgical site infections. The SHA holds promise not only for use in the operating theater, but also in understaffed healthcare environments where automation can improve healthcare delivery.

In this study, we present USDL, a novel model that employs deep learning algorithms in order to reconstruct and enhance corrupted ultrasound images. We utilize an unsupervised neural network called an autoencoder which works by compressing its input into a latent-space representation and then reconstructing the output from this representation. We trained our model on a dataset that compromises of 15,700 in vivo images of the neck, wrist, elbow, and knee vasculature and compared the quality of the images generated using the structural similarity index (SSIM) and peak to noise ratio (PSNR). In closely simulated conditions, the architecture exhibited an average reconstruction accuracy of 90% as indicated by our SSIM. Our study demonstrates that USDL outperforms state of the art image enhancement and reconstruction techniques in both image quality and computational complexity, while maintaining the architecture efficiency.