Sensitivity Range Research Articles

Comparison of Proxy-Shortwave Cloud Albedo from SBUV Observations with CMIP6 Models

Abstract We construct a long-term record of top of atmosphere (TOA) shortwave (SW) albedo of clouds and aerosols from 340-nm radiances observed by NASA and NOAA satellite instruments from 1980 to 2013. We compare our SW cloud+aerosol albedo with simulated cloud albedo from both AMIP and historical CMIP6 simulations from 47 climate models. While most historical runs did not simulate our observed spatial pattern of the trends in albedo over the Pacific Ocean, four models qualitatively simulate our observed patterns. Those historical models and the AMIP models collectively estimate an equilibrium climate sensitivity (ECS) of ∼3.5°C, with an uncertainty from 2.7° to 5.1°C. Our ECS estimates are sensitive to the instrument calibration, which drives the wide range in ECS uncertainty. We use instrument calibrations that assume a neutral change in reflectivity over the Antarctic ice sheet. Our observations show increasing cloudiness over the eastern equatorial Pacific and off the coast of Peru as well as neutral cloud trends off the coast of Namibia and California. To produce our SW cloud+aerosol albedo, we first retrieve a black-sky cloud albedo (BCA) and empirically correct the sampling bias from diurnal variations. Then, we estimate the broadband proxy albedo using multiple nonlinear regression along with several years of CERES cloud albedo to obtain the regression coefficients. We validate our product against CERES data from the years not used in the regression. Zonal mean trends of our SW cloud+aerosol albedo show reasonable agreement with CERES as well as the Pathfinder Atmospheres–Extended (PATMOS-x) observational dataset. Significance Statement Equilibrium climate sensitivity is a measure of the rise in global temperature over hundreds of years after a doubling of atmospheric CO2 concentration. Current state-of-the-art climate models forecast a wide range of equilibrium climate sensitivities (1.5°–6°C), due mainly to how clouds, aerosols, and sea surface temperatures are simulated within these models. Using data from NASA and NOAA satellite instruments from 1980 to 2013, we first construct a dataset that describes how much sunlight has been reflected by clouds over the 34 years and then we compare this data record to output from 47 climate models. Based on these comparisons, we conclude the best estimate of equilibrium climate sensitivity is about 3.5°C, with an uncertainty range of 2.7°–5.1°C.

How accurate do self-reported seizures need to be for effective medication management in epilepsy?

Studies suggest that self-reported seizure diaries suffer from 50% under-reporting on average. It is unknown to what extent this impacts medication management. This study used simulation to predict the seizure outcomes of a large heterogeneous clinic population treated with a standardized algorithm based on self-reported seizures. Using CHOCOLATES, a state-of-the-art realistic seizure diary simulator, 100 000 patients were simulated over 10 years. A standard algorithm for medication management was employed at 3 month intervals for all patients. The impact on true seizure rates, expected seizure rates, and time-to-steady-dose were computed for self-reporting sensitivities 0%-100%. Time-to-steady-dose and medication use mostly did not depend on sensitivity. True seizure rate decreased minimally with increasing self-reporting in a non-linear fashion, with the largest decreases at low sensitivity rates (0%-10%). This study suggests that an extremely wide range of sensitivity will have similar seizure outcomes when patients are clinically treated using an algorithm similar to the one presented. Conversely, patients with sensitivity ≤10% would be expected to benefit (via lower seizure rates) from objective devices that provide even small improvements in seizure sensitivity.

Green synthesis and studies on citrus medica leaf extract-mediated Au–ZnO nanocomposites: A sustainable approach for efficient photocatalytic degradation of rhodamine B dye in aqueous media

Abstract Incorporating narrow band gap oxide semiconductors and metals into zinc oxide (ZnO) nanostructures broadens the range of light sensitivity to include visible wavelengths. In this study, the photocatalytic degradation of rhodamine B (RhB) dye was studied as a model for environmental pollution in aqueous media. This study describes the use of photodegradation catalysts, including gold (Au), ZnO, and Au–ZnO nanocomposites (prepared in ratios of 90:10 and 95:5) using the extract of Citrus medica leaves. X-ray diffraction (XRD) findings have shown that ZnO nanoparticles (NPs) have a hexagonal wurtzite structure. Field emission-scanning electron microscopy findings have depicted that ZnO NPs have diverse shapes, including spherical, quasi-spherical, hexagonal, and anisotropic, with some clumping. Au exhibits consistent spherical shapes and sizes with even distribution. Au–ZnO (90:10) shows quasi-spherical NPs with interconnected spherical Au, forming a porous and uneven surface. Au–ZnO (95:5) has spherical gold nanoparticles (Au NPs) dispersed on a textured ZnO surface, with some clustering and size variation as evident from the transmission electron microscopy, atomic force microscopy, and diffuse reflectance UV-visible spectroscopy analysis. The characterization results have demonstrated the uniform distribution of Au across the ZnO lattice. Additionally, the XRD patterns confirmed the hexagonal wurtzite structure of ZnO. Furthermore, energy-dispersive analysis of X-ray (EDX)-mapping verified the inclusion of zinc, oxygen, and Au in the hybrid Au–ZnO nanocomposites and their effective distribution. The topological analysis revealed a rough surface for the generated nanostructures. By comparing the results of various techniques, EDX analysis using atomic and weight ratios confirmed the presence of oxygen and Au in the nanocomposite. Additionally, the surface area analysis (BET) test has reported that the adsorption and desorption of nitrogen follow a Type III isotherm. The presence of an H3-type hysteresis loop further confirms the mesoporous nature of the composites, which reports the presence of wedge-shaped pores. The Au–ZnO (90:10) nanocomposite exhibits a higher surface roughness compared to other composites. In addition, this UV-visible diffuse reflectance spectroscopy has enumerated the band gaps of various nanomaterials using UV-visible spectroscopy. Moreover, the analysis has unveiled that combining ZnO with Au NPs (doping) improved the photocatalytic performance of ZnO. This improvement is attributed to the formation of additional energy levels within the ZnO band gap due to the presence of Au ions. Experimental investigation of the breakdown of RhB dye under visible light irradiation revealed superior photocatalytic activity for the Au–ZnO (90:10) nanocomposite compared to both Au–ZnO (95:5) and pure ZnO and Au counterparts. Multiple experiments confirmed the effective photodegradation and removal of RhB dye from the aqueous medium using the nanocatalyst under visible light irradiation. Under optimal conditions (1.0 g·L−1 photocatalyst, 10 ppm RhB, and pH 10), 99% photodegradation efficiency was reached within 50 min of irradiation. Investigation of reactive species revealed that the increased effectiveness of photodegradation in Au–ZnO (90:10) stems from the presence of photogenerated holes and hydroxyl radicals. The study also analyzed the reaction kinetics and order, and the reusability of the best photocatalyst Au–ZnO (90:10)) was confirmed through five consecutive cycles, demonstrating its sustained effectiveness in photodegradation. These findings highlight the potential of Au–ZnO (90:10) nanocomposite as a promising material for photocatalytic degradation of organic dyes.

Wind Power Integration and Challenges in Low Wind Zones. A Study Case: Albania

High wind performance systems are influenced by many factors such as site wind resources and configuration, technical wind turbine features and many financial conditions. Scenario planning and modelling activities often focus on restricted parameters and numbers to justify wind power plant performance. To better understand possible pathways to scaling up the distributed wind market in Albania, a deep and multidimensional calculations based on Monte Carlo analysis, using RETScreen and wind JEDI model, to assess socio-economic impact as a function of turbine output power, operating and maintenance cost and many other financial inputs by testing different WT (i.e., VESTAS, GAMESA, W2E and NORDEX) with rated power from 3.45 MW up to 4.5MW applied on LCOE, NPV, SPP, equity payback, B-C, after-tax IRR on equity and effects of GHG credits extended at a sensitivity range of ±35% is scientifically performed. From the simulation results LCOE reaches a minimal value of €43.48/MWh, if the debt rate is 99 % and a debt interest rate of 5.0%, a TotCapEx of €828/MW (-35 % less expenditures) indexed as the best scenario. For the base case scenario LCOE results €62.79/MWh, when applying a debt rate of 80% and a TotCapEx of (€1274/MW), while in the worst-case scenario LCOE impart a maximal value of €87.63/MWh if a TotCapEx of €1720/MW (+35 % more expenditures) and a share of 52 % debt rate is applied. Local annual economic impact (m€) during construction period and operating period evaluated in the wind JEDI model result around m€ 89.92 and m€ 23.54, respectively. As a conclusion, wind power plants (WPP), installed in low wind zones (Albania and many other EU countries) would be of interest if an electricity export rate of 110€/MWh, and a GHG credit rate of €50/tCO2 were accepted.

The Echocardiographic Diagnosis of Rheumatic Heart Disease: A Review of the Performance of the World Heart Federation Criteria 2012-2023.

The World Heart Federation (WHF) published the first evidence-based guidelines on the echocardiographic diagnosis of rheumatic heart disease (RHD) in 2012. These guidelines have since been applied internationally in research and clinical practice. Substantial research has assessed the utility of the 2012 WHF criteria, including its applicability in low-resource settings. This article summarises the evidence regarding the performance of the guidelines. A scoping review assessing the performance of the guidelines was performed. Cochrane, Embase, Medline, PubMed Lilacs, Sielo, and Portal BVS databases were searched for studies on the performance of the guidelines between January 2012-March 2023, and 4047 manuscripts met the search criteria, of which 34 were included. This included papers assessing the specificity, inter-rater reliability, application using hand-carried ultrasound, and modification of the criteria for simplicity. The review followed the PRISMA Extension for Scoping Reviews guideline. The WHF 2012 criteria were 100% specific for definite RHD when applied in low-prevalence populations. The criteria demonstrated substantial and moderate inter-rater reliability for detecting definite and borderline RHD, respectively. The inter-rater reliability for morphological features was lower than for valvular regurgitation. When applied to hand-carried ultrasound performed by an expert, modified versions of the criteria demonstrated a sensitivity and specificity range of 79-90% and 87-93% respectively for detecting any RHD, performing best for definite RHD. The sensitivity and the specificity were reduced when performed in task-sharing but remains moderately accurate. The WHF 2012 criteria provide clear guidance for the echocardiographic diagnosis of RHD that is reproducible and applicable to a range of echocardiographic technology. Furthermore, the criteria are highly specific and particularly accurate for detecting definite RHD. There are limitations in applying all aspects of the criteria in specific settings, including task-sharing. This summary of evidence can inform the updated version of the WHF guidelines to ensure improved applicability in all RHD endemic regions.

Validation of the AgraStrip® Pro Total Aflatoxin WATEX® Method for Detection of Total Aflatoxins in Corn and Peanut Paste: AOAC Performance Tested MethodSM 032402.

To protect public and animal health against risks provoked by aflatoxins contained therein, maximum limits for aflatoxins are defined. Limit values vary depending on the intended use and regulatory authority, therefore quantitative detection is essential. Validation of a one-step competitive lateral flow immunochromatographic assay for quantitative screening of total aflatoxin (B1, B2, G1 and G2) in corn and peanut paste for the High Sensitivity Range (0-50 µg/kg). Corn or peanut paste test portions are water-based extracted and prepared for testing within 15 minutes. The AgraStrip Pro Total Aflatoxin WATEX test method quantifies the concentration of aflatoxins in the sample. Selectivity, robustness, product consistency and stability were performed in addition to matrix testing. No cross-reactivity was detected against possible interferants. Corn resulted in a LOD and LOQ of 0.9 and 2.8 µg/kg and overall recoveries between 74 and 108%. Peanut paste resulted internally in a LOD and LOQ of 0.8 and 2.3 µg/kg and recoveries between 86 and 98%. Stability testing showed no influence of the age of the respective lot on the result. Robustness testing demonstrated that varying the amount of water used for extraction, extraction time, and delay between extract dilution and analysis did not significantly affect the result. Due to supply chain issues, a change to the outer cartridge required an increase in the test aliquot size, which had no effect on method performance. The test kit was validated for the determination of total aflatoxins in corn and peanut paste. Recovery and precision met the requirements laid down in Codex Alimentarius CXG 71-2009 and acceptable robustness, selectivity, and product consistency and stability were demonstrated. The AgraStrip Pro Total Aflatoxin WATEX test kit in the high sensitivity range (0-50 µg/kg) was approved by the AOAC RI (PTM number 032402).

A liquid metal-embedded 3D interconnected-porous TPU/MXene composite with improved capacitive sensitivity and pressure detection range.

Flexible capacitive sensors are widely deployed in wearable smart electronics. Substantial studies have been devoted to constructing characteristic material architectures to improve their electromechanical sensing performance by facilitating the change of the electrode layer spacing. However, the air gaps introduced by the designed material architectures are easily squeezed when subjected to high-pressure loads, resulting in a limited increase in sensitivity over a wide range. To overcome this limitation, in this work, we embed the liquid metal (LM) in the internally interconnected porous structure of a flexible composite foam to fabricate a flexible and high-performance capacitive sensor. Different from the conventional conductive elements filled composite, the incompressible feature of the embedded fluidic LM leads to significantly improved mechanical stability of the composite foam to withstand high pressure loadings, resulting in a wider pressure sensing range from 10 Pa to 260 kPa for our capacitive composite sensor. Simultaneously, the metal conductivity and liquid ductility of the embedded LM endow the as-fabricated capacitive sensor with outstanding mechanical flexibility and pressure sensitivity (up to 1.91 kPa-1). Meanwhile, the LM-embedded interconnected-porous thermoplastic polyurethane/MXene composite sensor also shows excellent reliability over 4000 long-period load cycles, and the response times are merely 60 ms and 110 ms for the loading and unloading processes, respectively. To highlight their advantages in various applications, the as-proposed capacitive sensors are demonstrated to detect human movements and monitor biophysical heart-rate signals. It is believed that our finding could extend the material framework of flexible capacitive sensors and offer new possibilities and solutions in the development of the next-generation wearable electronics.

Modeling approach for Ti3C2 MXene-based fluorescent aptasensor for amoxicillin biosensing in water matrices

Amoxicillin, a member of the penicillin family, is primarily utilized for the treatment of various bacterial infections affecting ears, nose, throat, urinary tract, and skin. Given its widespread application in medicine, agriculture, environment, and food industry, the precise and sensitive detection of amoxicillin is important. This study introduces a novel approach to developing a sensitive and selective fluorescent aptasensor relying on fluorescence resonance energy transfer (FRET) for the specific detection of amoxicillin. The carboxyfluorescein-labeled aptamer serves as a energy donor, while MXene functions as an energy acceptor, and acting as a quencher. To achieve optimal detection efficiency, a dual optimization strategy utilizing RSM-CCD and ANN-GA was used to fine-tune experimental conditions. The fluorescence measurements revealed an expansive linear range extending from 100 to 2400 ng mL−1, accompanied by an exceptionally low detection limit of 1.53 ng mL−1. Additionally, it shows an excellent selectivity towards amoxicillin over other antibiotics commonly found in water matrices. The aptasensor demonstrates good stability and reproducibility; effectiveness of the aptasensor was validated by testing in real water samples. This remarkable sensitivity and broad dynamic range affirm the efficacy aptasensor in accurately detecting varying concentrations of amoxicillin in wastewater bodies.

Specific Small-Molecule Detection Using Designed Nucleic Acid Nanostructure Carriers and Nanopores.

In the realm of nanopore sensor technology, an enduring challenge lies in achieving the discerning detection of small biomolecules with a sufficiently high signal-to-noise ratio. This study introduces a method for reliably quantifying the concentration of target small molecules, utilizing tetrahedral DNA nanostructures as surrogates for the captured molecules through a magnetic-bead-based competition substitution mechanism. Magnetic Fe3O4-DNA tetrahedron nanoparticles (MNPs) are incorporated into a nanopore electrochemical system for small-molecule sensing. In the presence of the target, the DNA tetrahedron, featuring an aptamer tail acting as a molecular carrier, detaches from the MNPs due to aptamer deformation. Following removal of the MNPs, the DNA tetrahedron bound to the target traversed the nanopore by applying a positive potential. This approach exhibits various advantages, including heightened sensitivity, selectivity, an improved signal-to-noise ratio (SNR), and robust anti-interference capabilities. Our findings demonstrate that this innovative methodology has the potential to significantly enhance the sensing of various small-molecule targets by nanopores, thereby advancing the sensitivity and dynamic range. This progress holds promise for the development of precise clinical diagnostic tools.

Ammonia-trapping multilayer polymer urease film amplifier coated surface plasmon resonance sensor for ultra-sensitive urea detection

In this paper, we have developed a new urea signal amplification technology based on a multilayer urease polymer film self-assembly structure for the first time, enabling the realization of ultra-accurate urea optical detection. We demonstrate the effectiveness of this technique based on surface plasmon resonance (SPR) platform. When the urea signal amplifier is combined with SPR sensors, multilayer urease polymer film contacts with urea molecules, the urea molecules are oxidated into NH3 and CO2, causing the pH increase, which weakens the electrostatic interaction between different polymer layers and induces the RI reduction of the multilayer urease film, thereby causing the shift of the SPR spectrum. Experiment results confirm that urea sensitivity has been improved 12-fold, and the limit of detection (LOD) has been optimized to less than 10−3 mmol/L. Furthermore, the anti-interference has been improved 22.8-fold and is kept even the interference signal strength increases by 100 times. Moreover, multilayered urease polymer leads to the increase of urease on the sensor surface, thus expanding the detection range of urea by 3.5 times. This provides a new way to solve the contradiction between high sensitivity and large measurement range of optical fiber biosensor. Importantly, the concept of using enzyme-loaded polymer films for signal amplification can be adapted for the detection of various other biomolecules by replacing the enzyme with a specific recognition element for the target molecule. This opens doors for developing highly sensitive and specific biosensors for diverse applications in healthcare, environmental monitoring, and food safety.

Novel Polyurethane Based, Fully Flexible, High-Performance Piezoresistive Sensor for Real-Time Pressure Monitoring.

Flexible piezoresistive pressure sensors are garnering substantial attention, in line with advancements in biointegrated and wearable electronics. However, a significant portion of piezoresistive pressure sensors suffer from the trade-off between sensitivity and pressure range. Moreover, the current piezoresistive sensors generally rely on a rigid metallic electrode, severely deteriorating their long-term durability. Herein, a fully flexible piezoresistive sensor coupling polyurethane (PU) based electrode and active sensing element is proposed to circumvent the aforementioned problems. By rationally regulating the double-permeable conductive networks within the PU matrix, an elastomeric electrode and sensing element are implemented, respectively. The assembled heterostructured configurations enable impressive sensitivity up to 7.023 kPa-1, broad pressure detection (up to 420 kPa), an ultralow pressure sensing limit (0.1 Pa), and extraordinary operation stability over 80000 cyclic pressings along with fast response/relaxation times (60 ms/80 ms). Additionally, the fully flexible sensor is capable of both real-time detection of physiological signals and mimicking keyboards, implying its viability as a high-performance pressure sensor.

Elastoacoustic wave propagation in a biphasic mechanical metamateriala).

Humans are sensitive to air-borne sound as well as to mechanical vibrations propagating in solids in the frequency range below 20 kHz. Therefore, the development of multifunctional filters for both vibration reduction and sound insulation within the frequency range of human sensitivity is a research topic of primary interest. In this paper, a high-contrast biphasic mechanical metamaterial, composed of periodic elastic solid cells with air-filled voids, is presented. By opening intercellular air-communicating channels and introducing channel-bridging solid-solid couplings, the frequency dispersion spectrum of the metamaterial can be modified to achieve complete and large bandgaps for acoustic and elastic waves. From a methodological viewpoint, the eigenproblem governing the free wave propagation is solved using a hybrid analytical-computational technique, while the waveform classification is based on polarization factors expressing the fraction of kinetic and elastic energies stored in the solid and fluid phases. Based on these theoretical results, a mechanical metafilter consisting of an array of a finite number of metamaterial cells is conceived to provide a technical solution for engineering applications. The forced response of the metafilter is virtually tested in a computational framework to assess its performance in passively controlling the propagation of broadband sound and vibration signals within solid and fluid environments. Quantitative results synthesized by transmission coefficients demonstrate that the metafilter can remarkably reduce the transmitted response in the frequency band of human sensitivity.

Acute Exercise Alters Skeletal Muscle DNA Methylation in Sedentary Participants

Skeletal muscle is a highly plastic tissue, adapting its structure and metabolism in response to various stimuli like exercise. This study aimed to determine the plasticity of skeletal muscle DNA methylation in response to an acute exercise bout in volunteers with a range of insulin sensitivities. We studied 14 sedentary participants (7 male/7 female): age = 34.5 ± 3.1 years, body mass index = 29.3 ± 1.9 kg/m2 and HbA1c = 5.3 ± 0.1 %. We performed VO2peak tests to determine exercise capacity (VO2peak = 25.5 ± 1.6 mL per Kg per minute) and euglycemic hyperinsulinemic clamps (Rd value = 5.9 ± 0.8 mg per Kg per minute) with vastus lateralis muscle biopsies before and 30 minutes after a single 48-minute exercise bout. We extracted DNA from the muscle biopsies and performed reduced representation bisulfite sequencing. After performing quality control on the sequencing data, 1,034,947 sites were included for downstream analyses. MethylSig analysis revealed 17,030 differentially methylated cytosines (DMC), 9,020 increased and 8,010 decreased. To identify biologically meaningful DMCs, we used a mean change of >10%, which resulted in 1,179 and 1,436 increased and decreased sites, respectively. Pathway analysis of the increased DMCs revealed an enrichment in efferocytosis, leukocyte transendothelial migration, and FOXO-mediated transcription of oxidative stress pathways. In addition, pathway analysis of the decreased DMCs revealed an enrichment in metabolic (type 2 diabetes/ PI3K-Akt signaling), actin cytoskeleton, integrin/extracellular matrix and calcium signaling pathways. Our study reveals that an acute exercise bout induces alterations in the DNA methylation of skeletal muscle, impacting specific pathways in individuals with varying degrees of insulin sensitivity. Notably, our findings underscore the remarkable plasticity of skeletal muscle tissue. This research was funded by the National Institutes of Health, grant number R01DK094013 (Dawn Coletta). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

A Self-powered Accelerometer with Over-range Detection for Vibration and Shock Based on Triboelectric-electromagnetic Mechanism

Accelerometers based on triboelectric nanogenerators (TENGs) have garnered significant interest in recent years. However, many of these devices lack a self-sustained power supply for autonomous wireless operations and a mechanism for over-range detection. Additionally, theoretical investigations on the sensitivity of TENG-based accelerometer s are scarce. In this work, a novel self-powered accelerometer for vibration and shock integrating a freestanding triboelectric-layer-based TENG (FT-TENG), two contact-separation TENGs (CS-TENGs) and an electromagnetic generator (EMG) is proposed and then investigated through both numerical simulations and experimental demonstrations. The EMG is used for vibration energy harvesting, exhibiting an impressive power output of 4.11mW under a vibration acceleration of 12m/s2. The FT-TENG and the CS-TENGs work for acceleration sensing and over-range detection respectively. Under vibration, the sensitivity and measurement range are related to the frequency of excitation, and the proposed accelerometer has the maximum sensitivity (0.75V·s2/m) at its natural frequency. For shock events, the sensitivity of the accelerometer is dominated by the shock duration in a short-duration range, which is estimated to be 0.12V·s2/m under a shock duration of 0.03s. This work not only contributes to the understanding of TENGs adopted for sensing but also creates potential applications of triboelectric and electromagnetic energy harvesting and provides a feasible design for autonomous wireless sensor nodes.

Deep-eutectic-solvent modulation of self-assembled multi-responsive films based on polyvinyl alcohol/cellulose nanocrystal and grape skin red for highly sensitive food monitoring

To enhance the mechanics performance, sensitivity and response range of multi-responsive photonic films, herein, a facile method for fabricating multi-responsive films is demonstrated using the evaporative self-assembly of a mixture of grape skin red (GSR), cellulose nanocrystal (CNC), polyvinyl alcohol (PVA) and deep eutectic solvent (DES). The prepared materials exhibited excellent thermal stability, strain properties, solvent resistance, ultraviolet (UV) resistance and antioxidant activity. Compared to a pure PVA film, the presence of GSR strengthened the antioxidant property of the film by 240.1 % and provided excellent UV barrier capability. The additional cross-linking of DES and CNC promoted more efficient phase fusion, yielding a film strain of 41.5 %. The addition of hydrophilic compound GSR, wetting and swelling due to the DES and the surface inhomogeneity of the films rendered the multi-responsive films high sensitivity, wide response range and multi-cyclic stability in environments with varying pH and humidity. A sample application showed that a PVA/CNC/DES film has the potential to differentiate between fresh, sub-fresh and fully spoiled shrimps. The above results help in designing intelligent thin film materials that integrate antioxidant properties, which help in monitoring the changes in food freshness and food packaging.

A turn-off fluorescent sensor based on Schiff base incorporating diformyl phenol moiety for the detection of Cu2+ in aqueous solution at nanomolar level and its application in living cells

Given the critical role of trace copper ion in human health, its sensitive detection in environmental and biological samples is crucial. We, herein, designed and synthesized a diformyl phenol-based turn-off fluorescent sensor ((5-(tert-butyl)-2-hydroxy-1,3-phenylene)bis (methanylylidene)) bis (azanylylidene)) bis(4-hydroxy-2H-chromen-2-one) (MH-4)) for the spectrofluorometric detection of Cu2+ ion, which has sensitive and selective fluorescence quenching over other competitive metal ions. The efficiency and fast response of the sensor were confirmed by UV–Visible, fluorescence spectral changes, which may be due to the formation of coordination bond between MH-4 and Cu2+ ions. The binding stoichiometry of MH-4 with Cu2+ was examined with the help of UV–Vis and fluorescence titrations, and Job’s plot, which gives a 1:1 coordination stoichiometry; this is further confirmed through MS studies. The binding constant of the complex was found to be 9.4 x 107 M−1. Then, the absorbance and fluorescence-based detection limits were calculated to define the sensitivity range of the proposed sensor and were found to be 69.30 nM and 37.40 nM, respectively. Finally, a live cell image study of MH-4 in L929 (murine aneuploid fibrosarcoma) cells was also performed to test the cell permeability of MH-4 and its effectiveness for selective detection of Cu2+ in living cells.

Fit-for-Purpose Ki-67 Immunohistochemistry Assays for Breast Cancer

New therapies are being developed for breast cancer, and in this process, some “old” biomarkers are reutilized and given a new purpose. It is not always recognized that by changing a biomarker’s intended use, a new biomarker assay is created. The Ki-67 biomarker is typically assessed by immunohistochemistry (IHC) to provide a proliferative index in breast cancer. Canadian laboratories assessed the analytical performance and diagnostic accuracy of their Ki-67 IHC laboratory-developed tests (LDTs) of relevance for the LDTs’ clinical utility.Canadian clinical IHC laboratories enrolled in the Canadian Biomarker Quality Assurance Pilot Run for Ki-67 in breast cancer by invitation. The Dako Ki-67 IHC pharmDx assay was employed as a study reference assay. The Dako central laboratory was the reference laboratory. Participants received unstained slides of breast cancer tissue microarrays with 32 cases and performed their in-house Ki-67 assays. The results were assessed using QuPath, an open-source software application for bioimage analysis. Positive percent agreement (PPA, sensitivity) and negative percent agreement (NPA, specificity) were calculated against the Dako Ki-67 IHC pharmDx assay for 5%, 10%, 20%, and 30% cutoffs.Overall, PPA and NPA varied depending on the selected cutoff; participants were more successful with 5% and 10%, than with 20% and 30% cutoffs. Only 4 of 16 laboratories had robust IHC protocols with acceptable PPA for all cutoffs. The lowest PPA for the 5% cutoff was 85%, for 10% was 63%, for 20% was 14%, and for 30% was 13%. The lowest NPA for the 5% cutoff was 50%, for 10% was 33%, for 20% was 50%, and for 30% was 57%.Despite many years of international efforts to standardize IHC testing for Ki-67 in breast cancer, our results indicate that Canadian clinical LDTs have a wide analytical sensitivity range and poor agreement for 20% and 30% cutoffs. The poor agreement was not due to the readout but rather due to IHC protocol conditions. International Ki-67 in Breast Cancer Working Group (IKWG) recommendations related to Ki-67 IHC standardization cannot take full effect without reliable fit-for-purpose reference materials that are required for the initial assay calibration, assay performance monitoring, and proficiency testing.

A systematic review and meta-analysis of major blood protein biomarkers that predict unfavorable outcomes in severe traumatic brain injury

IntroductionSevere traumatic brain injury (TBI) presentation and late clinical outcomes are usually evaluated by the Glasgow Outcome Scale-Extended (GOS-E), which lacks strong prognostic predictability. Several blood biomarkers have been linked to TBI, such as Tau, GFAP, UCH-L1, S-100B, and NSE. Clinical values of TBI biomarkers have yet to be evaluated in a focused multi-study meta-analysis. We reviewed relevant articles evaluating potential relationships between TBI biomarkers and both early and 6-month outcomes. MethodsAll PubMed article publications from January 2000 to November 2023 with the search criteria “Protein Biomarker” AND “Traumatic Brain Injury” were included. Amongst all comparative studies, the sensitivity means and range values of biomarkers in predicting CT Rotterdam scores, ICU admission in the early period, or predicting GOS-E < 4 at the 6-month period were calculated from confusion matrices. Sensitivity values were modeled for each biomarker across studies and compared statistically for heterogeneity and differences. ResultsFrom the 65 articles that met the criteria, 13 were included in this study. Six articles involved early-period TBI outcomes and seven involved 6-month outcomes. In the early period TBI outcomes, GFAP had a superior sensitivity to UCH-L1 and S-100B, and similar sensitivity to the CT Rotterdam score. In the 6-month period TBI outcomes, total Tau and NSE both had significant interstudy heterogeneity, making them inferior to GFAP, phosphorylated Tau, UCH-L1, and S-100B, all four of which had similar sensitivities at 75 %. This sensitivity range at 6-month outcomes was still relatively inferior to the CT Rotterdam score. Total Tau did not show any prognostic advantage at six months with GOS-E < 4, and phosphorylated Tau was similar in its sensitivity to other biomarkers such as GFAP and UCH-L1 and still inferior to the CT Rotterdam score. ConclusionThis data suggests that TBI protein biomarkers do not possess better prognostic value with regards to outcomes.

Sustainable synthesis of praseodymium tungstate: An electrochemical probe for detection of Ronidazole

Profligate consumption of antibiotics in animal and livestock husbandry indulged in antibiotic pollution. This collapses the natural balance of the ecosystem and results in various environmental health crises. Herein, we have developed an ultra-sensitive praseodymium tungstate (PWO) based electrochemical sensor to detect one such serious antibiotic, Ronidazole (RD). A facile synthesis strategy was applied to prepare PWO nanomaterial and their structural, functional, and elemental details were thoroughly examined with a wide range of spectroscopic measurements. The electrochemical properties were determined by performing impedance and voltammetry experiments. The high catalytic efficiency of the designed sensor was achieved by optimizing its performance under different parameters. Based on the outcomes, the designed PWO-based sensor offered an extremely low level of detection (0.3 nM) and exhibited a wide range of linearity (0.001 µM to 20.4 µM), high sensitivity (7.72 µA µM−1 cm−2), and good selectivity. Further, the performance of the electrochemical sensor was validated with good repeatability, reproducibility, and stability results. The practical applicability of the sensor was investigated by monitoring the RD in aquatic, biological, and pharmaceutical samples. The obtained results affirmed that the PWO sensor is an efficient platform for the real-time monitoring of RD.

Analytical and clinical evaluation of the cobas Epstein–Barr virus test at a tertiary care cancer hospital

BackgroundEpstein–Barr Virus (EBV) viral loads in hematopoietic stem cell transplant (HSCT) recipients are typically monitored using quantitative molecular assays. The Cobas EBV test (Roche Molecular, Pleasanton, CA) has recently been FDA-cleared for the monitoring of EBV viral loads in plasma samples of transplant patients. In this study, we compared the viral loads obtained by a laboratory-developed test (EBV LDT) using Altona Analyte specific reagents (ASR) to those obtained on the Cobas EBV test. MethodsThe analytical performance of the assay was established using the EBV verification panel from Exact Diagnostics and the EBV ATCC strain B95-8. The clinical evaluation was performed using 343 plasma samples initially tested on the EBV LDT. ResultsThe analytical sensitivity (<18.8 IU/mL), precision (SD < 0.17 log) and linear range (35.0 IU/mL to 1E + 08 IU/mL) of the Cobas EBV assay established by the manufacturers were confirmed. The strength of the qualitative agreement was substantial between the cobas EBV and the EBV LDT (85.6 %; κ = 0.71) and almost perfect when discordant results were resolved (96.4 %; κ = 0.93). The quantitative agreement was moderate (82.9 %; κ = 0.53) with the viral load obtained on the Cobas EBV test being lower across the linear range of the two tests (mean log difference of 1.0). While the absolute values of the viral loads were markedly different, the overall trends observed in patients with multiple consecutive results were similar between the two tests. ConclusionsThe Cobas EBV test provides an accurate and valid, in vitro diagnostic (IVD) option for monitoring of EBV viral loads in transplant patients and should provide an opportunity for increased standardization and commutability of tests results across laboratories.