Potential Monitoring Research Articles

Utility of transcranial motor-evoked potential changes in predicting postoperative deficit in lumbar decompression and fusion surgery: a systematic review and meta-analysis.

The primary aim of this study was to evaluate whether TcMEP alarms can predict the occurrence of postoperative neurological deficit in patients undergoing lumbar spine surgery. The secondary aim was to determine whether the various types of TcMEP alarms including transient and persistent changes portend varying degrees of injury risk. This was a systematic review and meta-analysis of the literature from PubMed, Web of Science, and Embase regarding outcomes of transcranial motor-evoked potential (TcMEP) monitoring during lumbar decompression and fusion surgery. The sensitivity, specificity, and diagnostic odds ratio (DOR) of TcMEP alarms for predicting postoperative deficit were calculated and presented with forest plots and a summary receiver operating characteristic curve. Eight studies were included, consisting of 4923 patients. The incidence of postoperative neurological deficit was 0.73% (36/4923). The incidence of deficits in patients with significant TcMEP changes was 11.79% (27/229), while the incidence in those without changes was 0.19% (9/4694). All TcMEP alarms had a pooled sensitivity and specificity of 63 and 95% with a DOR of 34.92 (95% CI 7.95-153.42). Transient and persistent changes had sensitivities of 29% and 47%, specificities of 96% and 98%, and DORs of 8.04 and 66.06, respectively. TcMEP monitoring has high specificity but low sensitivity for predicting postoperative neurological deficit in lumbar decompression and fusion surgery. Patients who awoke with new postoperative deficits were 35 times more likely to have experienced TcMEP changes intraoperatively, with persistent changes indicating higher risk of deficit than transient changes. Diagnostic Systematic Review.

Effect of intraoperative muscle relaxation reversal on the success rate of motor evoked potential recording in patients undergoing spinal surgery: a randomized controlled trial

BackgroundPartial neuromuscular blockade (NMB) has been applied for some surgeries to reduce bleeding and prevent patient movement for spinal surgery. Sugammadex selectively binds to rocuronium in the plasma and consequently lowers the rocuronium concentration at the neuromuscular junction. In this study, we aimed to observe whether the success rate of transcranial motor-evoked potential (TceMEP) can be increased by sugammadex compared with partial NMB during spinal surgery.MethodsPatients who underwent elective spinal surgery with TceMEP monitoring were randomly assigned to the sugammadex group and control group. Rocuronium was continuously infused to maintain the train of four counts (TOFc) = 2. The sugammadex group discontinued rocuronium infusion at the time of TceMEP monitoring and was infused with 2 mg/kg sugammadex; the control group was infused with the same dose of saline.ResultsA total of 171 patients were included. The success rate of TceMEP monitoring in the sugammadex group was significantly higher than that in the control group. TceMEP amplitudes were greater in the sugammadex group than in the control group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. The latencies of upper extremity TceMEPs monitoring showed no difference between groups. TOF ratios were greater in the sugammadex group at 5 min, 10 min, and 20 min after the start of motor-evoked potential monitoring. There were no adverse effects caused by sugammadex.ConclusionsSugammadex can improve the success rate of motor-evoked potential monitoring compared with moderate neuromuscular blockade induced by continuous infusion of rocuronium in spinal surgery.Trial registrationThe study was registered on clinicaltrials.gov.cn on 29/10/2020 (trial registration number: NCT04608682).

Electrospun Rubber Nanofiber Web-Based Dry Electrodes for Biopotential Monitoring.

This study aims to find base materials for dry electrode fabrication with high accuracy and without reducing electrode performance for long-term bioelectric potential monitoring after electroless silver plating. Most applications of dry electrodes that have been developed in the past few decades are restricted by low accuracy compared to commercial Ag/AgCl gel electrodes, as in our previous study of PVDF-based dry electrodes. In a recent study, however, nanoweb-based chlorinated polyisoprene (CPI) and poly(styrene-b-butadiene-b-styrene) (SBS) rubber were selected as promising candidates due to their excellent elastic properties, as well as their nanofibril nature, which may improve electrode durability and skin contact. The electroless silver plating technique was employed to coat the nanofiber web with silver, and silver nanoweb(AgNW)-based dry electrodes were fabricated. The key electrode properties (contact impedance, step response, and noise characteristics) for AgNW dry electrodes were investigated thoroughly using agar phantoms. The dry electrodes were subsequently tested on human subjects to establish their realistic performance in terms of ECG, EMG monitoring, and electrical impedance tomography (EIT) measurements. The experimental results demonstrated that the AgNW dry electrodes, particularly the SBS-AgNW dry electrodes, performed similarly to commercial Ag/AgCl gel electrodes and were outperformed in terms of long-term stability.

Global microbial water quality data and predictive analytics: Key to health and meeting SDG 6

Microbial water quality is an integral to water security and is directly linked to human health, food safety, and ecosystem services. However, specifically pathogen data and even faecal indicator data (e.g., E. coli), are sparse and scattered, and their availability in different water bodies (e.g., groundwater) and in different socio-economic contexts (e.g., low- and middle-income countries) are inequitable. There is an urgent need to assess and collate microbial data across the world to evaluate the global state of ambient water quality, water treatment, and health risk, as time is running out to meet Sustainable Development Goal (SDG) 6 by 2030. The overall goal of this paper is to illustrate the need and advocate for building a robust and useful microbial water quality database and consortium worldwide that will help achieve SDG 6. We summarize available data and existing databases on microbial water quality, discuss methods for producing new data on microbial water quality, and identify models and analytical tools that utilize microbial data to support decision making. This review identified global datasets (7 databases), and regional datasets for Africa (3 databases), Australia/New Zealand (6 databases), Asia (3 databases), Europe (7 databases), North America (12 databases) and South America (1 database). Data are missing for low- and middle-income countries. Increased laboratory capacity (due to COVID-19 pandemic) and molecular tools can identify potential pollution sources and monitor directly for pathogens. Models and analytical tools can support microbial water quality assessment by making geospatial and temporal inferences where data are lacking. A genomics, information technology (IT), and data revolution is upon us and presents unprecedented opportunities to develop software and devices for real-time logging, automated analysis, standardization, and modelling of microbial data to strengthen knowledge of global water quality. These opportunities should be leveraged for achieving SDG 6 around the world.

Wolf genetic diversity compared across Europe using the yardstick method

Integrating data across studies with traditional microsatellite genetic markers requires careful calibration and represents an obstacle for investigation of wide-ranging species where populations require transboundary management. We used the “yardstick” method to compare results published across Europe since 2002 and new wolf (Canis lupus) genetic profiles from the Carpathian Mountains in Central Europe and the Dinaric Mountains in Southeastern Europe, with the latter as our reference population. We compared each population with Dinaric wolves, considering only shared markers (range 4–17). For each population, we calculated standard genetic diversity indices plus calibrated heterozygosity (Hec) and allelic richness (Ac). Hec and Ac in Dinaric (0.704 and 9.394) and Carpathian wolves (0.695 and 7.023) were comparable to those observed in other large and mid-sized European populations, but smaller than those of northeastern Europe. Major discrepancies in marker choices among some studies made comparisons more difficult. However, the yardstick method, including the new measures of Hec and Ac, provided a direct comparison of genetic diversity values among wolf populations and an intuitive interpretation of the results. The yardstick method thus permitted the integration of diverse sources of publicly available microsatellite data for spatiotemporal genetic monitoring of evolutionary potential.

Recent Advances in Intraoperative Brainstem Auditory Evoked Potential Monitoring during Microvascular Decompression Surgery for Hemifacial Spasm.

Brainstem auditory evoked potential (BAEP) testing during microvascular decompression (MVD) is very important in the treatment of hemifacial spasm (HFS). The reason for this is that the vestibulocochlear nerve is located immediately next to the facial nerve, so the vestibulocochlear nerve may be affected by manipulation during surgery. BAEP testing for detecting vestibulocochlear nerve damage has been further developed for use during surgery. In most HFS patients with normal vestibulocochlear nerves, the degree of vestibulocochlear nerve damage caused by surgery is well-reflected in the BAEP test waveforms. Therefore, real-time testing is the best way to minimize damage to the vestibulocochlear nerve. The purpose of this study was to review the most recently published BAEP test waveforms that were obtained during MVD surgery to determine the relationship between vestibulocochlear nerve damage and BAEP waveforms.

Could extended laminectomy effectively prevent spinal cord injury due to spinal shortening after 3-column osteotomy?

ObjectiveTo explore whether the laminectomy extension can effectively prevent spinal cord injury (SCI) due to spinal shortening after 3-column osteotomy in goat models.MethodsA total of twenty healthy goats were included and done with 3-column osteotomy of T13 and L1 under the somatosensory evoked potential (SSEP) monitoring. The samples were divided into two groups. The first group underwent regular laminectomy while the second group underwent an extended laminectomy with an extra 10 mm-lamina cranial to L2. The SSEP measured after 3-column osteotomy was set as the baseline, and the SSEP decreased by 50% from the baseline amplitude and/or delayed by 10% relative to the baseline peak latency was set as positive results, which indicated spinal cord injury. The vertebral column was gradually shortened until the SSEP monitoring just did not show a positive result. The height of the initial osteotomy gap (the distance from the lower endplate of T12 to the upper endplate of L2), the shortened distance (△H), the number of spinal cord angulated and the changed angle of the spinal cord (△α) were measured and recorded in each group. Neurological function was evaluated by the Tarlov scores on day 2 postoperatively.ResultsAll the goats except one of the first group due to changes in the SSEP during the osteotomy were included and analyzed. In the first group, the height of the initial osteotomy segment and the safe shortening distances were 61.6 ± 2.6 mm and 35.2 ± 2.6 mm, respectively; the spinal cord of 5 goats was angulated (46.4 ± 6.6°), the other four goats were kinked and not angulated. In the second group, the height of the initial osteotomy segment and the safe shortening distances were 59.8 ± 1.5 mm and 43.3 ± 1.2 mm, respectively, and the spinal cord of ten goats were angulated (97.6 ± 7.2°). There was no significant difference in the height of the initial osteotomy segment between the two groups by using Independent-Samples T-Test, P = 0.095 (P > 0.05); there were significant difference in the safe shortening distance and the changed angle of the spinal cord between the two groups by using Independent-Samples T-Test (both DeltaH and Deltaα of P < 0.001), the difference between their mean were 8.1 mm and 51.2°. Significant difference was found in the number of spinal cord angulation between the two groups through Fisher’s exact test (5/9 vs. 10/10, P = 0.033).ConclusionsAn additional resection of 10 mm-lamina cranial to L2 showed the satisfactory effect in alleviating SCI after 3-column osteotomy. Timely and appropriate extend laminectomy could be a promising therapeutic strategy for SCI attributable to facilitating spinal cord angulation rather than spinal cord kinking and increasing the safe shortening distance.

Total Intravenous Anesthesia Protocol for Decreasing Unacceptable Movements during Cerebral Aneurysm Clipping with Motor-Evoked Potential Monitoring: A Historical Control Study and Meta-Analysis.

Injury can occur during intraoperative transcranial motor-evoked potential (MEP) monitoring caused by patient movement related to insufficient neuromuscular blocking agent use. Here, we evaluated the incidence of unacceptable movements in patients undergoing intraoperative MEP monitoring following our anesthetic protocol. We reviewed the anesthesia records of 419 patients who underwent unruptured cerebral aneurysm clipping with intraoperative MEP monitoring. The anesthetic protocol included target-controlled infusion with a fixed effect-site propofol concentration of 3 μg/mL and an adjustable effect-site remifentanil concentration of 10-12 ng/mL. We compared our findings of the intraoperative parameters and incidence of spontaneous movement and respiration with those of published meta-analysis studies. Spontaneous movement and respiration occurred in one (0.2%) patient each. The meta-analysis included six studies. The pooled proportions of spontaneous movement and respiration were 6.9% (95% confidence interval [CI], 1.3-16.5%) and 4.1% (95% CI, 0.5-14.1%), respectively. The proportion of spontaneous movement in our study was significantly lower than that in previous studies (p = 0.013), with no significant difference in spontaneous respiration (p = 0.097). Following our center's anesthesia protocol during cerebral aneurysm clipping resulted in a low incidence of spontaneous respiration and movement, indicating its safety for patients undergoing intraoperative MEP monitoring.

Efficient biodegradation of the recalcitrant organochlorine pesticide chlordecone under methanogenic conditions

Anaerobic digestion (AD) has long been studied as an effective environmental and economic strategy for treating matrices contaminated with recalcitrant pollutants. In the present work, we investigated the bioremediation potential of AD on organic waste contaminated with chlordecone (CLD), an organochlorine pesticide extensively used in the French West Indies and classified among the most persistent organic pollutants. Digestates from animal and plant origins were supplemented with CLD and incubated under methanogenic conditions for over 40 days. The redox potential and pH monitoring showed that methanogenic conditions were preserved during the entire incubation period despite the presence of CLD. In addition, the comparison of the total biogas generated from digestates with and without CLD demonstrated no adverse effects of CLD on biogas production. For the first time, a QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction method, followed by GC–MS and LC-HRMS analyses, was developed to quantify CLD and its main known transformation products (TPs) in AD experiments. A decrease in CLD concentrations was evident to a greater extent under thermophilic conditions (55 °C) compared to mesophilic conditions (37.5 °C) (CLD removal of 85 % and 42 %, respectively, after 40 days of incubation). CLD degradation was confirmed by the detection and quantification of several TPs: 10-monohydroCLD (A1), two dihydroCLDs different from 2,8-dihydroCLD (A3), pentachloroindene (B1), tetrachloroindenes (B2, B3/B4), tetra- and tri-chloroindenecarboxylic acids (C1/C2, C3/C4). Determining TPs concentrations using the QuEChERS method provided an overview of CLD fate in AD. Overall, these results reveal that AD processes can efficiently degrade CLD into several TPs from A, B, and C families while maintaining satisfactory biogas production. They pave the way to developing a scaled-up AD process capable of treating CLD-contaminated organic wastes produced by farming, thus stopping any further transfer of CLD.

Synthesis of ethanolic and aqueous extracts of sponge gourd peels and their application for the prevention of mild steel corrosion in saline water

Natural and waste materials could be a successful and economical strategy for saving metals from corrosion because they could easily exchange electrons with the metals through their biomolecules. This work reported the use of waste sponge gourd peels (SGP) for the suppression of mild steel (MS) loss after dipping in 0.5 M NaCl. The water and ethanolic extracts of sponge gourd peels (SGPAE and SGPEE) had been prepared and characterized by Fourier transform infrared spectroscopy (FTIR). Both extracts were found to be loaded with biomolecules. SGPAE was used as an inhibitor, and SGPEE was utilized as a coating. Different concentrations (50–300 mg L−1) of SGPAE were added to 0.5 M NaCl, and SGPEE layers (1–5) were deposited on MS via drop casting and then exposed to salty water. The corrosion testing had been performed by open circuit potential (OCP) monitoring, Tafel polarization curves (TC), electrochemical impedance spectroscopy (EIS), field ion emission scanning electron microscopy (FESEM), energy dispersive X-ray spectra (EDX), and atomic force microscopy (AFM). The testing had shown that both extracts were effective against MS corrosion. SGPAE had shown maximum inhibition at 200 mg L−1 (75%), and SGPEE had shown maximum protection of 83% for 4 layers. The cause of MS protection by SGP was claimed to be the coverage of MS by the adsorbed molecules (SGPAE) or thin barrier layers of molecules (SGPEE). The reason for protection was also explained through an illustration.

Dynamic evaluation of blood immune cells predictive of response to immune checkpoint inhibitors in NSCLC by multicolor spectrum flow cytometry.

Immune checkpoint inhibitors (ICIs) only benefit a subset of cancer patients, underlining the need for predictive biomarkers for patient selection. Given the limitations of tumor tissue availability, flow cytometry of peripheral blood mononuclear cells (PBMCs) is considered a noninvasive method for immune monitoring. This study explores the use of spectrum flow cytometry, which allows a more comprehensive analysis of a greater number of markers using fewer immune cells, to identify potential blood immune biomarkers and monitor ICI treatment in non-small-cell lung cancer (NSCLC) patients. PBMCs were collected from 14 non-small-cell lung cancer (NSCLC) patients before and after ICI treatment and 4 healthy human donors. Using spectrum flow cytometry, 24 immune cell markers were simultaneously monitored using only 1 million PBMCs. The results were also compared with those from clinical flow cytometry and bulk RNA sequencing analysis. Our findings showed that the measurement of CD4+ and CD8+ T cells by spectrum flow cytometry matched well with those by clinical flow cytometry (Pearson R ranging from 0.75 to 0.95) and bulk RNA sequencing analysis (R=0.80, P=1.3 x 10-4). A lower frequency of CD4+ central memory cells before treatment was associated with a longer median progression-free survival (PFS) [Not reached (NR) vs. 5 months; hazard ratio (HR)=8.1, 95% confidence interval (CI) 1.5-42, P=0.01]. A higher frequency of CD4-CD8- double-negative (DN) T cells was associated with a longer PFS (NR vs. 4.45 months; HR=11.1, 95% CI 2.2-55.0, P=0.003). ICIs significantly changed the frequency of cytotoxic CD8+PD1+ T cells, DN T cells, CD16+CD56dim and CD16+CD56- natural killer (NK) cells, and CD14+HLDRhigh and CD11c+HLADR + monocytes. Of these immune cell subtypes, an increase in the frequency of CD16+CD56dim NK cells and CD14+HLADRhigh monocytes after treatment compared to before treatment were associated with a longer PFS (NR vs. 5 months, HR=5.4, 95% CI 1.1-25.7, P=0.03; 7.8 vs. 3.8 months, HR=5.7, 95% CI 169 1.0-31.7, P=0.04), respectively. Our preliminary findings suggest that the use of multicolor spectrum flow cytometry helps identify potential blood immune biomarkers for ICI treatment, which warrants further validation.

Postacute coronavirus disease‐2019 syndrome: Review of the literature and role of the pharmacist

AbstractSevere acute respiratory syndrome coronavirus (SARS‐CoV‐2) has resulted in over 500 million confirmed cases of coronavirus disease‐2019 (COVID‐19) worldwide, causing over 6 million deaths. A wide disease spectrum has been described for COVID‐19 infections with a newer focus on the long‐term impacts termed Postacute COVID‐19 syndrome (PACS). PACS is not formally defined but occurs 4 weeks to 6 months after the acute infection impacting the neurologic, cardiovascular, respiratory, gastrointestinal, endocrine, renal, dermatologic, and hematologic organ systems to varying degrees. Nearly one third of patients will experience a neuropsychiatric manifestation within 6 months of a COVID‐19 diagnosis with anxiety, depression, and posttraumatic stress disorder (PTSD) being the most common symptoms. There is much similarity between PACS and Postintensive care syndrome (PICS). Long‐term follow‐up is necessary to ensure intensive care unit (ICU) survivors are cared for appropriately. The development of PICS clinics across the world has set a groundwork for better managing PACS. The inclusion of clinical pharmacists in these clinics has repeatedly improved outcomes. Implementation of the ABCDEF Bundle prevents the occurrence of PICS and PACS, making it an important discussion point for the entire health care team. Epidemiologic data is still emerging with the National Institute of Health (NIH) researching COVID to enhance recovery (RECOVER) research initiative contributing to our understanding of PACS and how to best manage it. The purpose of this review paper is to characterize PACS and recommend prevention, potential monitoring, and treatment, as well as to highlight the role of the clinical pharmacist in the management of this population.

Prediction of interference current of buried pipeline and study on corrosion of Q235A steel

Interference current will cause severe electrochemical corrosion to buried pipes. However, the interference current flowing into the buried pipeline cannot be directly measured, and the influence of interference current on the corrosion of the buried pipeline cannot be directly observed. In this paper, the combined analysis methods of finite element analysis, partial least square method and electrochemical measurement technique are used to predict the interference current of buried pipeline and to study the effect of dynamic interference current and chloride ion concentration on the corrosion of Q235A steel. The prediction results show that increasing the input variables of the prediction model and changing the position of the input variables can effectively improve the accuracy of the model. Electrochemical measurements show that an increase in chloride ion concentration increases the corrosion current density in the polarization curve of Q235A steel and decreases the capacitive reactance arc radius in the electrochemical impedance spectroscopy. In addition, on the basis of the rail-to-ground potential monitoring points in the actual project, the number of rail-to-ground potential monitoring points was increased to improve the prediction accuracy of the buried pipeline interference currents, which indicates that the analysis method is an effective way to monitor and evaluate the influence of stray currents on the corrosion of buried pipelines.

Physics-informed deep learning for rock physical inversion and its uncertainty analysis

Geological CO2 storage is aiming to inject the carbon dioxide into subsurface formations, and geophysical measurements are then commonly used to monitor the fluid long-term and safe storage for risk assessment during and after the injection. In this process, the rock physical inversion is an essential part for determining the reservoir parameters such as porosity or fluid saturation for potential storage calculation or monitoring fluid migration. We propose a deep learning approach to invert reservoir parameters based on rock properties or seismically inverted results. The rock physics equations are incorporated into the learning process, leading the neural networks as physics informed. We choose the generative adversarial networks to obtain ensemble predictions by varying the input latent vectors, from which the uncertainty analysis is performed. The proposed approach is applied to the Sleipner 2019 Benchmark Model for inverting reservoir porosity and CO2 saturation with rock properties in terms of velocities and bulk density as inputs. The supervised learning and physics-informed neural network are also applied for a comparison; however, both of them cannot access the prediction uncertainty that is important for risk reduction by decision makers.

Intraoperative Neuromonitoring of the Visual Pathway in Asleep Neuro-Oncology Surgery.

Brain tumour surgery in visual eloquent areas poses significant challenges to neurosurgeons and has reported inconsistent results. This is a single-centre prospective cohort study of patients admitted for asleep surgery of intra-axial lesions in visual eloquent areas. Demographic and clinical information, data from tractography and visual evoked potentials (VEPs) monitoring were recorded and correlated with visual outcomes. Thirty-nine patients were included (20 females, 19 males; mean age 52.51 ± 14.08 years). Diffuse intrinsic glioma was noted in 61.54% of patients. There was even distribution between the temporal, occipital and parietal lobes, while 55.26% were right hemispheric lesions. Postoperatively, 74.4% remained stable in terms of visual function, 23.1% deteriorated and 2.6% improved. The tumour infiltration of the optic radiation on tractography was significantly related to the visual field deficit after surgery (p = 0.016). Higher N75 (p = 0.036) and P100 (p = 0.023) amplitudes at closure on direct cortical VEP recordings were associated with no new postoperative visual deficit. A threshold of 40% deterioration of the N75 (p = 0.035) and P100 (p = 0.020) amplitudes correlated with a risk of visual field deterioration. To conclude, direct cortical VEP recordings demonstrated a strong correlation with visual outcomes, contrary to transcranial recordings. Invasion of the optic radiation is related to worse visual field outcomes.

Wearable Flexible Perspiration Biosensors Using Laser-Induced Graphene and Polymeric Tape Microfluidics.

Wearable biosensors promise real-time measurements of chemicals in human sweat, with the potential for dramatic improvements in medical diagnostics and athletic performance through continuous metabolite and electrolyte monitoring. However, sweat sensing is still in its infancy, and questions remain about whether sweat can be used for medical purposes. Wearable sensors are focused on proof-of-concept designs that are not scalable for multisubject trials, which could elucidate the utility of sweat sensing for health monitoring. Moreover, many wearable sensors do not include the microfluidics necessary to protect and channel consistent and clean sweat volumes to the sensor surface or are not designed to be disposable to prevent sensor biofouling and inaccuracies due to repeated use. Hence, there is a need to produce low-cost and single-use wearable sensors with integrated microfluidics to ensure reliable sweat sensing. Herein, we demonstrate the convergence of laser-induced graphene (LIG) based sensors with soft tape polymeric microfluidics to quantify both sweat metabolites (glucose and lactate) and electrolytes (sodium) for potential hydration and fatigue monitoring. Distinct LIG-electrodes were functionalized with glucose oxidase and lactate oxidase for selective sensing of glucose and lactate across physiological ranges found in sweat with sensitivities of 26.2 and 2.47 × 10-3 μA mM-1 cm-2, detection limits of 8 and 220 μM, and linear response ranges of 0-1 mM and 0-32 mM, respectively. LIG-electrodes functionalized with a sodium-ion-selective membrane displayed Nernstian sensitivity of 58.8 mV decade-1 and a linear response over the physiological range in sweat (10-100 mM). The sensors were tested in a simulated sweating skin microfluidic system and on-body during cycling tests in a multisubject trial. Results demonstrate the utility of LIG integrated with microfluidics for real-time, continuous measurements of biological analytes in sweat and help pave the way for the development of personalized wearable diagnostic tools.

Performance of Anticorrosive Measures of Steel in Concrete Infrastructure by Plant‐Based Extracts

AbstractCompetence to combat corrosion of steel‐reinforced concrete (SRC) infrastructures for long periods has become a fascinating topic for corrosion scientists. The longevity of such infrastructures is limited mainly by the corrosion process. Hence, urgent demands for developing effective and practical methods are necessary to minimize the corrosion of such concrete structures. The anti‐corrosive components can be designed from the green plants' parts to mitigate the SRC corrosion in recent years. The ongoing research aims to substantiate the success of the leaf extract of Psidium guajava (LEPG) and its 50% blend (BnD) with the leaf extract of Mangifera indica (LEMI) for assessing the steel corrosion condition in a concrete slab. For this purpose, a fast corrosion potential monitoring (CPM) method is applied per the ASTM procedure. Outcomes of the work summarized that the additions of 500–4000 ppm LEPG and its 50% BnD blend have significant corrosion‐inhibiting action. The corrosion potential (ϕcorr) shifts toward a less corrosion‐risk area of the steel bar for 6 months at ambient conditions.

Towards Monitoring and Identification of Red Palm Weevil Gender Using Microwave CSRR-Loaded TL Sensors.

This paper presents for the first time the design of a microwave sensing setup for the potential monitoring and identification of red palm weevil (RPW) gender type. The microwave sensor consists of a planar two-port transmission line (TL) with a single complementary split-ring resonant (CSRR) inclusion etched from the bottom metallic layer. The CSRR sensor is placed on top of a customized non-conductive container. The microwave sensing setup was designed, numerically demonstrated, fabricated and tested experimentally. Simulated results correlate quite well with the experimental data. Moreover, the sensitivity of the CSRR sensor when in close proximity to different RPW genders was evaluated both numerically and experimentally. Based on the measured results from 15 RPW samples with different body sizes, different RPW gender types showed unique microwave signatures. A notable shift in the sensor's resonance frequency was achieved, where on average a resonant frequency shift of 10% for adult RPWs was achieved, while a 2.4% frequency change was obtained for larvae (young) RPWs. Hence, the proposed microwave sensing setup can be adopted in field trials to examine and differentiate between various RPW genders at various developmental stages.

Combining voltage-sensitive dye, carbon fiber array, and extracellular nerve electrodes using a 3-D printed recording chamber and manipulators

BackgroundThe analyses of neuronal circuits require high-throughput technologies for stimulating and recording many neurons simultaneously with single-neuron precision. Voltage-sensitive dyes (VSDs) have enabled the monitoring of membrane potentials of many (10–100 s) neurons simultaneously. Carbon fiber electrode (CFE) arrays allow for stimulation and recording of many neurons simultaneously, including intracellularly. New methodCombining CFE with VSD leverages the advantages of both technologies, allowing for stimulation of single neurons while recording the activity of the entire network. 3-D printing technology was used to develop a chamber to simultaneously perform VSD imaging, CFE array recording, and extracellular recording from individual glass electrodes. ResultsAplysia buccal ganglia were stained with VSD and imaged while also recording using a CFE array and extracellular nerve electrodes. Coincident spiking activity was recorded by VSD, CFE, and extracellular nerve electrodes. Current injection with CFE electrodes could activate and inhibit individual neurons as detected by VSD and nerve recordings. Comparison to existing methodsThe large size of traditional manipulators limits the number of electrodes used and the number of neurons recorded during an experiment. Here we present a method to build a 3-D printed recording chamber that includes a 3-axis micromanipulator to position a CFE array and eight 2-axis manipulators to position eight extracellular electrodes. Conclusions3-D printing technology can be used to build a custom recording chamber and micromanipulators. Combining these technologies allows for the direct modulation of the activity of neurons while recording the activity of 100 s of neurons simultaneously.

Portable electrical impedance tomography (EIT) system stages non-alcoholic fatty liver disease for potential screening and monitoring at home.

This study demonstrates the feasibility of predicting NAFLD using multi-spectral electrical impedance tomography (EIT), group source separation, constant reference EIT and anthropometric measures. Vibration-controlled Transient Elastography (VCTE) Controlled Attenuated Parameter (CAP; n = 121) and magnetic resonance imaging-proton density fat fraction (MRI-PDFF; n = 34) achieved a sensitivity of 70.9% and specificity of 73.8% with our CAP predicting model and sensitivity of 77.8% and specificity of 80.0% with our MRI-PDFF predicting model. In summary, a portable EIT can be a cost-effective and self-administrable alternative for widespread home-based and community-based diagnostic screening and treatment monitoring of NAFLD.Clinical Relevance- Portable multi-spectral EIT system has the sensitivity and specificity to potentially unlock biomedical imaging in telemedicine for home-based and community-based screening, staging and monitoring for NAFLD.