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Neuromuscular ultrasound is a painless, radiation‐free, high‐resolution imaging technique for assessing the peripheral nervous system. It can accurately depict changes in the nerves and muscles of individuals with neuromuscular conditions, and it is therefore a robust diagnostic tool for the assessment of individuals with polyneuropathies. This review will outline the typical ultrasonographic changes found in a wide variety of polyneuropathies. In general, demyelinating conditions result in greater nerve enlargement than axonal conditions, and acquired conditions result in more patchy nerve enlargement compared to diffuse nerve enlargement in hereditary conditions. This review is data‐driven, but more nuanced anecdotal findings are also described. The overall goal of this paper is to provide clinicians with an accessible review of the ultrasonographic approaches and findings in a wide variety of polyneuropathies. [ABSTRACT FROM AUTHOR]

Objective: To assess the role of serum neurofilament light chain (NfL) levels in individuals with diabetic polyneuropathy (DPN) compared with controls, as well as to highlight the different sonographic changes in DPN and determine if NfL correlates with sonographic, clinical, and functional parameters. Methods: Diabetic individuals with signs or symptoms consistent with peripheral nerve involvement were recruited. They were evaluated by examination, functional neuropathy severity scores, laboratory assessments (including NfL), nerve conduction studies (NCS), and ultrasound. Ultrasound was performed of the bilateral median, ulnar, tibial, fibular, sural, and vagus nerves, and cervical roots 5 and 6. Results were compared with age, sex, and body mass index matched healthy controls. Results: A total of 320 nerves from 20 patients and 480 nerves from 30 controls were evaluated. NfL was significantly elevated in those with diabetes with a mean and standard deviation of 6.95 ± 2.95 pg/mL in the diabetic group and 2.83 ± 0.77 pg/mL in controls (P <.001). Nerve cross‐sectional area and serum NfL levels correlated significantly with clinical and functional parameters and with each other (P <.05). Conclusion: Individuals with DPN have significantly higher NfL levels than healthy controls, and NfL levels correlate with ultrasonographic parameters. These findings may be useful for the diagnosis, prognosis, and disease monitoring of those with DPN, though further exploration is needed. [ABSTRACT FROM AUTHOR]

Objectives: To explore neurofilament light chain (NfL) levels in leprotic neuropathy compared to controls, and to determine if the changes correlate with ultrasonographic nerve findings. Methods: Individuals with leprosy with signs or symptoms suggestive of peripheral nerve involvement were recruited. They were evaluated by clinical examination, functional scores, laboratory assessments (including NfL), nerve conduction studies (NCS), and ultrasound. Ultrasound was conducted in bilateral median, ulnar, tibial, fibular, sural, and vagus nerves as well as cervical roots 5 and 6. Results were compared to age, sex, and body mass index matched healthy controls. Results: A total of 320 nerves from 20 patients and 480 nerves from 30 controls were evaluated. NfL was significantly elevated in those with leprosy with a mean and standard deviation of 7.50 + 2.83 compared with 3.42 + 1.18 in controls (P <.001). Ultrasound showed focal enlargement of the nerves, particularly at entrapment sites. Additionally, there were noticeable changes in neural Doppler signal, echogenicity, and epineural thickness among the measured nerve sites. NfL levels in those with leprosy correlated closely with nerve cross‐sectional area at all sites (P <.05). Functional and clinical assessment scores correlated with NfL and sonographic cross‐sectional area as well (P ≤.05). Conclusions: NfL is elevated in leprotic neuropathy. Ultrasound showed specific morphological changes in individuals with leprosy, and nerve enlargement correlated with NfL levels. Thus, both modalities may be useful for the diagnosis, prognosis, and disease monitoring in those with leprotic neuropathy, and further investigations are warranted. [ABSTRACT FROM AUTHOR]

The worldwide demand for reduced and restricted use of pesticides in agriculture due to serious environmental effects, health risks and the development of pathogen resistance calls for the discovery of new bioactive compounds. In the medical field, antibiotic‐resistant microorganisms have become a major threat to man, increasing mortality. Endophytes are endosymbiotic microorganisms that inhabit plant tissues without causing any visible damage to their host. Many endophytes secrete secondary metabolites with biological activity against a broad range of pathogens, making them potential candidates for novel drugs and alternative pesticides of natural origin. We isolated endophytes from wild plants in Israel, focusing on endophytes that secrete secondary metabolites with biological activity. We isolated 302 different endophytes from 30 different wild plants; 70 of them exhibited biological activity against phytopathogens. One biologically active fungal endophyte from the genus Penicillium, isolated from a squill (Urginea maritima) leaf, was further examined. Chloroform‐based extraction of its growth medium was similarly active against phytopathogens. High‐performance liquid chromatography separation followed by gas chromatography/mass spectrometry analysis revealed a single compound—mycophenolic acid—as the main contributor to the biological activity of the organic extract. [ABSTRACT FROM AUTHOR]

Non‐orthogonal multiple access (NOMA) allows multiple user equipment (UE) to simultaneously share the same resource blocks using varying levels of transmit power at the base station (BS) side. Proper allocation of transmission power and selection of candidate users for pairing over the same resource block are critical for an efficient utilization of the available resources. Optimal UE selection and power splitting among paired UEs can be made through an exhaustive search over the space of all possible solutions. However, the cost incurred by such approach can render it practically infeasible. Reinforcement learning (RL) deploying double deep‐Q networks (DDQN) is a promising framework that can be adopted for tackling the problem. In this article, an RL‐based DDQN scheme is proposed for user pairing in opportunistic access to downlink NOMA systems with capacity‐limited backhaul link connections. The proposed algorithm relies on proactive data caching to alleviate the throttling caused by backhaul bottlenecks, and optimized UE selection and power allocation are accomplished through the continuous interaction between an RL agent and the NOMA environment to increase the overall system throughput. Simulation results are presented to showcase the near‐optimal strategy achieved by the proposed scheme. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

In this study, downlink channel estimation of three-dimensional massive multiple-input multiple-output (3D-MIMO) system operating in the frequency division duplexing (FDD) mode is considered. Inspired by the channel sparsity property, this study proposes a compressive sensing algorithm to exploit the channel sparsity structure in the angle-time domain. The proposed algorithm, named AMP-ADM, combines the multiple approximate message passing (M-AMP) algorithm with the alternative direction of multiplier (ADM) technique to efficiently exploit the sparsity structure of the 3D massive MIMO channel. First, the proposed AMP-ADM is implemented in the case of the conventional estimation for the FDD protocol where the channel is estimated individually at each user equipment. Then, building on this algorithm, a low complexity feedback AMP-ADM-T scheme at the transmitting base station (BS) side is proposed. In the proposed feedback AMP-ADM-T technique the users' channels are jointly estimated at the BS to fully exploit the common sparsity basis. Complexity and convergence analyses are provided for both the AMP-ADM and feedback AMP-ADM-T algorithms. Simulation results prove the improved performance of the proposed feedback AMP-ADM-T algorithm compared to different state-of-the-art joint channel estimation techniques. [ABSTRACT FROM AUTHOR]

Abstract: Salt precipitation over porous media due to evaporation is known to affect various important processes, including evaporation itself. Many studies have shown that salt crust precipitation reduces evaporation rate, and it has been suggested that the crust constitutes a barrier to vapor flow. Nevertheless, it remains unclear how a porous medium such as the salt crust does not enable upward liquid water transfer by capillary flow. Herein, we show by various imaging methods that the salt crust grows out of specific nucleation centers, to create an elevated crust approximately 1 mm above the matrix surface, most of which is disconnected from the matrix. This indicates that evaporation from a porous medium that is covered by NaCl efflorescence salt crust may occur below the crust, at the soil surface. [ABSTRACT FROM AUTHOR]

Using time domain reflectometry (TDR), we studied stem water content (θstem), stem electrical conductivity (σstem), and their ratio for 220 d in stressed, installation-cured, living trees of four species. Lysimeter-grown mango (Mangifëra indica L.), banana (Musa acuminata Colla), date (Phoenix dactylifera L.), and olive (Olea europaea L.) were subjected to several types of mild (intensity and duration) water stresses simulating horticultural orchard irrigation practices. This study of living trees was triggered by our previous study accomplished in uncured, thawed, native, cut stem segments. We have confirmed in living trees our earlier findings that θstem reacts sensitively and within minutes to water stress. This response is the main driver of θstem changes, by far exceeding the salinity effect on σstem. Known irrigation rates, half-hourly tree weights from load cells, and frequent sampling of drainage solution for volume and salinity independently confirmed our findings. Relative to θstem, resistivity measurements have lower scatter because θstem-dielectric constant (e) relationships are exponential and θstem-resistivity relationships are linear. With resistivity, there is no need to match impedances among meter, cable, and probe, implying a larger flexibility in probe geometry, longer cables, and higher accuracy with shorter rods. There is a clear economic advantage in resistivity over C measurements. The linkage between stem resistivity and water status (designated as the linkage factor) for lysimeter plants, orchard trees, and cut stem segments demonstrates the potential in scheduling irrigation according to plant water needs with an inexpensive, direct, and simple resistivity measurement. [ABSTRACT FROM AUTHOR]

Root parasitic weeds of the genera Striga, Orobanche, and Phelipanche cause enormous economic losses for farmers the world over. Germination of the seeds of these species requires a chemotropic signal in the form of strigolactones in the soil. Once a root parasitic weed germinates and becomes established, it draws nutrition from the host plants, leading to plant death and hence yield reduction. Despite the obvious importance of strigolactones, there is currently almost no information about the fate of strigolactones in the soil, although microbial involvement has been suggested. To begin to address this knowledge lacuna, we developed a bioassay—using the strigolactone synthetic analogue GR24—as a high‐throughput, inexpensive, and compact tool for monitoring the dissipation of strigolactones (GR24 in this case) in the soil by microorganisms and/or environmental conditions, including GR24 concentration, soil type, and temperature. As part of the bioassay, it was found that autoclaving the soil delayed the dissipation of GR24 versus sterilisation by gamma radiation and or no sterilisation. Analytical LC–MS/MS with a detection limit of 0.1 ppb confirmed this finding, with no GR24 being detected in non‐sterilised soil after 24 h. Application of the bioassay to monitor GR24 dissipation in soil showed that the higher the GR24 concentration the slower the degradation, and the higher the temperature, the faster the degradation. It also showed that the organic matter content of the soil affected the GR24 dissipation rate. These findings were also confirmed by analytical LC–MS/MS, indicating the applicability of the methodology for studies of root exudes. [ABSTRACT FROM AUTHOR]

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Background: In situ cellular reprogramming offers the possibility of regenerating functional cardiomyocytes directly from scar fibroblasts, obviating the challenges of cell implantation. We hypothesized that pretreating scar with gene transfer of the angiogenic vascular endothelial growth factor (VEGF) would enhance the efficacy of this strategy., Methods and Results: Gata4, Mef2c, and Tbx5 (GMT) administration via lentiviral transduction was demonstrated to transdifferentiate rat fibroblasts into (induced) cardiomyocytes in vitro by cardiomyocyte marker studies. Fisher 344 rats underwent coronary ligation and intramyocardial administration of an adenovirus encoding all 3 major isoforms of VEGF (AdVEGF-All6A(+)) or an AdNull control vector (n=12/group). Lentivirus encoding GMT or a GFP control was administered to each animal 3 weeks later, followed by histologic and echocardiographic analyses. GMT administration reduced the extent of fibrosis by half compared with GFP controls (12 ± 2% vs 24 ± 3%, P<0.01) and reduced the number of myofibroblasts detected in the infarct zone by 4-fold. GMT-treated animals also demonstrated greater density of cardiomyocyte-specific marker beta myosin heavy chain 7(+) cells compared with animals receiving GFP with or without VEGF (P<0.01). Ejection fraction was significantly improved after GMT vs GFP administration (12 ± 3% vs -7 ± 3%, P<0.01). Eight (73%) GFP animals but no GMT animals demonstrated decreased ejection fraction during this interval (P<0.01). Also, improvement in ejection fraction was 4-fold greater in GMT/VEGF vs GMT/null animals (17 ± 2% vs 4 ± 1%, P<0.05)., Conclusions: VEGF administration to infarcted myocardium enhances the efficacy of GMT-mediated cellular reprogramming in improving myocardial function and reducing the extent of myocardial fibrosis compared with the use of GMT or VEGF alone.