Effect of Deep Learning Image Reconstruction on Image Quality and Pericoronary Fat Attenuation Index.

To compare the image quality and fat attenuation index (FAI) of coronary artery CT angiography (CCTA) under different tube voltages between deep learning image reconstruction (DLIR) and adaptive statistical iterative reconstruction V (ASIR-V). Three hundred one patients who underwent CCTA with automatic tube current modulation were prospectively enrolled and divided into two groups: 120 kV group and low tube voltage group. Images were reconstructed using ASIR-V level 50% (ASIR-V50%) and high-strength DLIR (DLIR-H). In the low tube voltage group, the voltage was selected according to Chinese BMI classification: 70 kV (BMI < 24 kg/m2), 80 kV (24 kg/m2 ≤ BMI < 28 kg/m2), 100 kV (BMI ≥ 28 kg/m2). At the same tube voltage, the subjective and objective image quality, edge rise distance (ERD), and FAI between different algorithms were compared. Under different tube voltages, we used DLIR-H to compare the differences between subjective, objective image quality, and ERD. Compared with the 120 kV group, the DLIR-H image noise of 70 kV, 80 kV, and 100 kV groups increased by 36%, 25%, and 12%, respectively (all P < 0.001); contrast-to-noise ratio (CNR), subjective score, and ERD were similar (all P > 0.05). In the 70 kV, 80 kV, 100 kV, and 120 kV groups, compared with ASIR-V50%, DLIR-H image noise decreased by 50%, 53%, 47%, and 38-50%, respectively; CNR, subjective score, and FAI value increased significantly (all P < 0.001), ERD decreased. Compared with 120 kV tube voltage, the combination of DLIR-H and low tube voltage maintains image quality. At the same tube voltage, compared with ASIR-V, DLIR-H improves image quality and FAI value.

Radiation and mechanical performance of cementitious materials containing ecofriendly nano laboratory waste glass.

This study helps in managing waste glass and greening the environment by incorporating laboratory waste glass into mortar production to make an eco-friendly shielding material against gamma rays. The efficiency of using waste glass powder as a cement replacement or addition in mortar production was studied by using two waste glass sizes: micro glass (particle size range from 10.09 to 24.73 µm) and nano glass (particle size range from 10.57 to 26.42 nm) to design different mortar specimens with varying percentages of fine glass powder from 0 to 30%. Compressive strength and flexure strength were evaluated to determine mechanical properties. The results indicated that adding WGP to mortar positively affects the characteristics of cementitious composites. The linear and mass attenuation coefficients of the samples were experimentally determined using a NaI detector and various radioactive sources (Am-241, Ba-133, Eu-152, Cs-137, and Co-60) with gamma energies ranging from 59.53 to 1332 keV. The obtained coefficients were then compared to the theoretical values of the composites using XCOM software to verify their accuracy. Additionally, the half-value layer, tenth-value layer, mean free path, and effective atomic number were computed. Furthermore, the results revealed that the mortar sample with 30% nano additive glass was the most effective in reducing gamma radiation.

Usefulness of fat attenuation index in postmortem CT for identifying responsible vessels in acute coronary syndromes: A case report.

Postmortem imaging, particularly unenhanced postmortem computed tomography (PMCT), has been increasingly utilized for pathological or judicial examination as a substitute for conventional autopsy, to compensate very low autopsy rates. While unenhanced PMCT has a limitation in diagnosing acute coronary syndromes, the fat attenuation index (FAI) which is a novel imaging biomarker measured by clinical coronary CT angiography (CCTA), has been known to noninvasively detect coronary artery inflammation. We investigated the postmortem diagnostic usefulness of perivascular FAI measured by CCTA in a 61-year-old male who died suddenly after chest pain. PMCT and autopsy were conducted 92 hours after death. FAI measurement results were -57 Hounsfield units (HU) in the right coronary artery (RCA), -73 HU in the left anterior descending artery (LAD), and -64 HU in the left circumflex artery (LCX). Autopsy revealed significant stenosis in the RCA and LCX, but no significant stenosis was found in the LAD. The elevated FAI in the RCA suggested acute inflammation, which agreed with the autopsy findings. This case is the first to demonstrate effectiveness of FAI measured with PMCT for identifying the vessels responsible for acute coronary syndromes, indicating its potential in postmortem diagnosis.

Experimental study on attenuation effect of liquid viscosity on shockwaves of cavitation bubbles collapse.

How to precisely control and efficiently utilize the physical processes such as high temperature, high pressure, and shockwaves during the collapse of cavitation bubbles is a focal concern in the field of cavitation applications. The viscosity change of the liquid will affect the bubble dynamics in turn, and further affect the precise control of intensity of cavitation field. This study used high-speed photography technology and schlieren optical path system to observe the spatiotemporal evolution of shockwaves in liquid with different viscosities. It was found that as the viscosity of the liquid increased, the wave front of the collapse shockwave of the cavitation bubble gradually thickened. Furthermore, a high-frequency pressure testing system was used to quantitatively analyze the influence of viscosity on the intensity of the shockwave. It was found that the pressure peak of the shockwave in different viscous liquid was proportional to Lb (L represented the distance between the center of bubble and the sensor measuring point), and the larger the viscosity was, the smaller the value of b was. Through in-depth analysis, it was found that as the viscosity of the liquid increased, the proportion of the shockwave energy of first bubble collapse to the maximal mechanical energy of bubble gradually decreased. The proportion of the mechanical energy of rebounding bubble to the maximal mechanical energy of bubble gradually increased. These new findings have an important theoretical significance for the efficient utilization of ultrasonic cavitation.

Relationship Between Calcified Plaque Burden, Vascular Inflammation, and Plaque Vulnerability in Patients With Coronary Atherosclerosis.

BACKGROUND: Coronary artery calcification is an integral part of atherosclerosis. It has been suggested that early coronary artery calcification is associated with active inflammation, and advanced calcification forms as inflammation subsides. Inflammation is also an important factor in plaque vulnerability. However, the relationship between coronary artery calcium burden, vascular inflammation, and plaque vulnerability has not been fully investigated. OBJECTIVES: This study aimed to correlate calcified plaque burden (CPB) at the culprit lesion with vascular inflammation and plaque vulnerability. METHODS: Patients with coronary artery disease who had both computed tomography angiography and optical coherence tomography were included. The authors divided the patients into 4 groups: 1 group without calcification at the culprit lesion; and 3 groups based on the CPB tertiles. CPB was calculated as calcified plaque volume divided by vessel volume in the culprit lesion. The authors compared pericoronary adipose tissue (PCAT) attenuation for vascular inflammation and optical coherence tomography-derived vulnerable features among the 4 groups. RESULTS: Among 578 patients, the highest CPB tertile showed significantly lower PCAT attenuation of culprit vessel compared with the other groups. The prevalence of features of plaque vulnerability (including lipid-rich plaque, macrophage, and microvessel) was also lowest in the highest CPB tertile. In the patients with calcification, higher age, statin use, and lower PCAT attenuation were independently associated with CPB. CONCLUSIONS: Greater calcium burden is associated with a lower level of vascular inflammation and plaque vulnerability. A greater calcium burden may represent advanced stable plaque without significant inflammatory activity. (Massachusetts General Hospital and Tsuchiura Kyodo General Hospital Coronary Imaging Collaboration; NCT04523194).

A Study on the Effects of Depth-Dependent Power Loss on Speckle Statistics Estimation.

Characterization of the interference patterns observed in B-mode images (i.e., speckle statistics) is a valuable tool in tissue characterization. However, changes in echo amplitudes unrelated to speckle, including power loss due to attenuation and diffraction, can bias these metrics, undermining their utility. Tissue with high attenuation such as the uterine cervix are especially affected. The purpose of this study was to demonstrate and quantify the effects of attenuation and diffraction on speckle statistics and to propose methods of compensation. Analysis was performed on simulated diffuse scattering phantoms of varying attenuation with simulated transducers at 9 and 5 MHz center frequency. Application in the in vivo macaque cervix using a clinical scanner is also presented. Nakagami and homodyned K distribution parameters were calculated in parameter estimation regions (PERs) of varying size within simulations and experiments. Changes in speckle statistics parameters with respect to PER size and depth were compared with and without two different compensation schemes. It has been shown that compensation for attenuation and diffraction is necessary to produce speckle statistics estimates that do not depend on medium attenuation or PER size. Reducing the dependence on these factors connects speckle statistics estimates more closely with the microstructure of the probed medium.

Recovery of Petroleum Brine-Contaminated Soil by Eleocharis sp. in a Tropical Marshland.

Almost all research on natural attenuation and phytoremediation of sites contaminated with briny produced water has been conducted in temperate climates, however, there is a dearth of information on the use of tropical species for this purpose. It is within this context, that we investigated a spontaneously growing hypersaline spikerush from a contaminated site in southeast Mexico, to determine its soil salinity limits, the relationship between soil organic matter and salinity, and for preliminary documentation of floristic succession with Typha sp. for phytoremediation o f brine s pills. Soil was sampled (0 cm-20 cm) three times between 2018-2021, focusing on the end of the dry season (most critical period). The species tentatively identified as Eleocharis mutata was tolerant to soil hypersalinity (Electrical Conductivity: 125 dS/m) and appeared to generate a cyclic process of succession to recover areas with soil salinity levels higher than it could otherwise tolerate. A salinity gradient was found between the most heavily contaminated part of the site ("kill zone", > 212 dS/m), the first Eleocharis sp. individuals (125 dS/m), slowly advancing through the main spikerush stand, and finally into a cattail stand (< 8.02 dS/m). Similarly, an inverse relationship between Soil Organic Matter content and soil salinity was observed. This is the first time this species has been identified with a brine spill, its salinity limits determined, and investigated for use in phytoremediation of this kind.

Assessment of lesion insertion tool in pelvis PET/MR data with applications to attenuation correction method development.

BACKGROUND: In modern positron emission tomography (PET) with multi-modality imaging (e.g., PET/CT and PET/MR), the attenuation correction (AC) is the single largest correction factor for image reconstruction. One way to assess AC methods and other reconstruction parameters is to utilize software-based simulation tools, such as a lesion insertion tool. Extensive validation of these simulation tools is required to ensure results of the study are clinically meaningful. PURPOSE: To evaluate different PET AC methods using a synthetic lesion insertion tool that simulates lesions in a patient cohort that has both PET/MR and PET/CT images. To further demonstrate how lesion insertion tool may be used to extend knowledge of PET reconstruction parameters, including but not limited to AC. METHODS: Lesion quantitation is compared using conventional Dixon-based MR-based AC (MRAC) to that of using CT-based AC (CTAC, a "ground truth"). First, the pre-existing lesions were simulated in a similar environment; a total of 71 lesions were identified in 18 pelvic PET/MR patient images acquired with a time-of-flight simultaneous PET/MR scanner, and matched lesions were inserted contralaterally on the same axial slice. Second, synthetic lesions were inserted into four anatomic target locations in a cohort of four patients who didn't have any observed clinical lesions in the pelvis. RESULTS: The matched lesion insertions resulted in unity between the lesion error ratios (mean SUVs), demonstrating that the inserted lesions successfully simulated the original lesions. In the second study, the inserted lesions had distinct characteristics by target locations and demonstrated negative max-SUV%diff trends for bone-dominant sites across the patient cohort. CONCLUSIONS: The current work demonstrates that the applied lesion insertion tool can simulate uptake in pelvic lesions and their expected SUV values, and that the lesion insertion tool can be extended to evaluate further PET reconstruction corrections and algorithms and their impact on quantitation accuracy and precision.

Measurement Method of Stress in High-Voltage Cable Accessories Based on Ultrasonic Longitudinal Wave Attenuation.

High-voltage cables are the main arteries of urban power supply. Cable accessories are connecting components between different sections of cables or between cables and other electrical equipment. The stress in the cold shrink tube of cable accessories is a key parameter to ensure the stable operation of the power system. This paper attempts to explore a method for measuring the stress in the cold shrink tube of high-voltage cable accessories based on ultrasonic longitudinal wave attenuation. Firstly, a pulse ultrasonic longitudinal wave testing system based on FPGA is designed, where the ultrasonic sensor operates in a single-transmit, single-receive mode with a frequency of 3 MHz, a repetition frequency of 50 Hz, and a data acquisition and transmission frequency of 40 MHz. Then, through experiments and theoretical calculations, the transmission and attenuation characteristics of ultrasonic longitudinal waves in multi-layer elastic media are studied, revealing an exponential relationship between ultrasonic wave attenuation and the thickness of the cold shrink tube. Finally, by establishing a theoretical model of the radial stress of the cold shrink tube, using the thickness of the cold shrink tube as an intermediate variable, an effective measurement of the stress of the cold shrink tube was achieved.

Unraveling the fate of 6PPD-Q in aquatic environment: Insights into formation, dissipation, and transformation under natural conditions.

The widespread occurrence of N-(1,3-Dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD-Q) in aquatic environments and its hazards to aquatic species underscore the necessity of comprehending its environmental fate. Here, we investigated the transformation from 6PPD to 6PPD-Q and the attenuation of 6PPD-Q in surface water under natural conditions. Contrary to prior findings, this work revealed that 6PPD-Q and its precursor 6PPD-OH/6PPD-(OH)2, were not detected through target analysis and suspect screening during 6PPD transformation in the surface water under the natural conditions. 6PPD-Q predominantly accumulated in TWPs in ambient atmosphere with 1.28 % mass yield from the 6PPD dissipation. Subsequently, 6PPD-Q was eluted from TWPs and released to the water environment. The investigation on the natural attenuation of 6PPD-Q in the surface water demonstrated that direct and indirect photolysis facilitated the rapid dissipation of 6PPD-Q with a half-life of 2.57 h. Utilizing the liquid chromatography high resolution mass spectrometry (LC-HRMS), including both time of flight (TOF) MS and Orbitrap MS, twelve novel transformation products (TPs) of 6PPD-Q were identified by using a comprehensive non-targeted screening strategy. The results from two dimensions gas chromatography (GC×GC) TOF-MS revealed additional two TPs. Based on the molecular structure of TPs, four major pathways of 6PPD-Q attenuation were proposed, including bond cleavage, hydroxylation, quinone cleavage and rearrangement. All TPs were predicted to exhibit lower toxicity, indicating the natural attenuation of 6PPD-Q reduced its toxicity and potential environmental risks. This study provides crucial insights into the environmental fate of 6PPD-Q, highlighting the significance of understanding both its formation from 6PPD and its subsequent attenuation processes under natural conditions.

Migration and natural attenuation of leachate pollutants in bedrock fissure aquifer at a valley landfill site.

Groundwater pollution from valley type landfills is concerning, and natural attenuation by contaminants is increasingly relied upon. However, the reliability of natural attenuation in such complex sites has been called into question due to incomplete understanding of their attenuation mechanisms. Therefore, we conducted field investigations, monitoring analyses, mathematical statistics, and machine learning techniques to elucidate the natural attenuation mechanisms of pollutants within bedrock fissures at a prototypical valley type landfill located in the east Yanshan Mountains, China. Our results indicate that 50% of the monitored indicators showed extreme pollution in bedrock fissure aquifers, due to seepage from the valley type landfill site. Ammonia nitrogen, arsenic, cadmium, lead, iron, manganese, and mercury were among the contaminants that could pose serious risks to human health. Pollutant concentrations in bedrock fissure aquifers were lower during the rainy season compared to the dry season as the aquifer was rapidly recharged by strong rainfall runoff. The initial concentration of bedrock fissure water generally increased during the flow through the landfill. However, significant natural attenuation of total dissolved solids, oxygen consumption, ammonia, cadmium, and lead occurred after passing through the landfill (p<0.05), with attenuation coefficients of 0.0041 m-1, 2.56×E-5m-2, 4.18×E-5m-2、0.0015 m-0.99, and 6.83×E-33m-12.49, respectively. The driving mechanisms for natural attenuation include physical migration, leaching, microbiological degradation, and adsorption, primarily occurring within 600-650 m downstream of the landfill boundary. This study makes fundamental contribution to the understanding of the migration and natural attenuation process of leachate pollutants in bedrock fissure aquifer, which will provide a scientific basis for implementation of natural attenuation strategies in complex site remediation. Future research should examine more precise evidence of natural attenuation feasibility in complex sites in conjunction with monitoring networks.

Enhancing Breast Cancer Detection through Advanced AI-Driven Ultrasound Technology: A Comprehensive Evaluation of Vis-BUS.

This study aims to enhance breast cancer detection accuracy through an AI-driven ultrasound tool, Vis-BUS, developed by Barreleye Inc., Seoul, South Korea. Vis-BUS incorporates Lesion Detection AI (LD-AI) and Lesion Analysis AI (LA-AI), along with a Cancer Probability Score (CPS), to differentiate between benign and malignant breast lesions. A retrospective analysis was conducted on 258 breast ultrasound examinations to evaluate Vis-BUS's performance. The primary methods included the application of LD-AI and LA-AI to b-mode ultrasound images and the generation of CPS for each lesion. Diagnostic accuracy was assessed using metrics such as the Area Under the Receiver Operating Characteristic curve (AUROC) and the Area Under the Precision-Recall curve (AUPRC). The study found that Vis-BUS achieved high diagnostic accuracy, with an AUROC of 0.964 and an AUPRC of 0.967, indicating its effectiveness in distinguishing between benign and malignant lesions. Logistic regression analysis identified that 'Fatty' lesion density had an extremely high odds ratio (OR) of 27.7781, suggesting potential convergence issues. The 'Unknown' density category had an OR of 0.3185, indicating a lower likelihood of correct classification. Medium and large lesion sizes were associated with lower likelihoods of correct classification, with ORs of 0.7891 and 0.8014, respectively. The presence of microcalcifications showed an OR of 1.360. Among Breast Imaging-Reporting and Data System categories, category C5 had a significantly higher OR of 10.173, reflecting a higher likelihood of correct classification. Vis-BUS significantly improves diagnostic precision and supports clinical decision-making in breast cancer screening. However, further refinement is needed in areas like lesion density characterization and calcification detection to optimize its performance.

Comparative Prognostic Value of Coronary Calcium Score and Perivascular Fat Attenuation Index in Coronary Artery Disease.

Coronary artery disease (CAD) is the leading global cause of mortality, accounting for approximately 30% of all deaths. It is primarily characterized by the accumulation of atherosclerotic plaques within the coronary arteries, leading to reduced blood flow to the heart muscle. Early detection of atherosclerotic plaques is crucial to prevent major adverse cardiac events. Notably, recent studies have shown that 15% of myocardial infarctions occur in patients with non-obstructive CAD, underscoring the importance of comprehensive plaque assessment beyond merely identifying obstructive lesions. Cardiac Computed Tomography Angiography (CCTA) has emerged as a cost-effective and efficient technique for excluding obstructive CAD, particularly in patients with a low-to-intermediate clinical likelihood of the disease. Recent advancements in CCTA technology, such as improved resolution and reduced scan times, have mitigated many technical challenges, allowing for precise quantification and characterization of both calcified and non-calcified atherosclerotic plaques. This review focuses on two critical physiological aspects of atherosclerotic plaques: the burden of calcifications, assessed via the coronary artery calcium score (CACs), and perivascular fat attenuation index (pFAI), an emerging marker of vascular inflammation. The CACs, obtained through non-contrast CT scans, quantifies calcified plaque burden and is widely used to stratify cardiovascular risk, particularly in asymptomatic patients. Despite its prognostic value, the CACs does not provide information on non-calcified plaques or inflammatory status. In contrast, the pFAI, derived from CCTA, serves as an indirect marker of coronary inflammation and has shown potential in predicting adverse cardiac events. Combining both CACs and pFAI assessment could offer a comprehensive risk stratification approach, integrating the established calcification burden with novel inflammatory markers to enhance CAD prevention and management strategies.

The reduction of nitrobenzene by Fe(II)-goethite-hematite heterogeneous systems: Insight from thermodynamic parameters of reduction potential.

Determining the contaminants reduction rate by dissolved ferrous iron (Fe(II)aq) bound to iron oxides is curial for evaluating the abiotic attenuation of contaminants in aquifers. However, few studies have assessed the contaminants reduction rate controlled by thermodynamic parameters in heterogeneous systems with different iron oxides. In this study, a linear free energy relationship (LFER) was established between the nitrobenzene reduction rate and the thermodynamic driving force (reduction potential (EH) and pH) in Fe(II)aq-goethite-hematite co-existing systems. Results showed that the reduction rate of nitrobenzene correlated with the EH of the heterogeneous system. The standard reduction potential (EH0mix) of the mixed iron oxides could be obtained by a proportionate linear combination of the single iron oxide system EH0. Based on this, the EH of the heterogeneous systems could be calculated theoretically by combining EH0mix and the Nernst equation. Furthermore, a parallel LFER with the slope of 1 was established to associate the nitrobenzene reduction rate with EH and pH. The intercept term was related to the adsorption capacity of different iron oxides towards Fe(II)aq. The Fe(II)aq saturation adsorption capacity of hematite was 1.5 times higher than that of goethite. After normalizing the nitrobenzene reduction rate to the Fe(II)aq saturation adsorption capacity, the maximum difference in intercept terms was reduced from 37% to 15%. These findings would provide an important and feasible methodological support for the quantitative evaluation of abiotic attenuation of contaminants in groundwater.

Ultrasound attenuation imaging as a strategy for evaluation of early and late ambulatory functions in Duchenne muscular dystrophy.

BACKGROUND: Duchenne muscular dystrophy (DMD) is a genetic neuromuscular disorder that leads to mobility loss and life-threatening cardiac or respiratory complications. Quantitative ultrasound (QUS) envelope statistics imaging, which characterizes fat infiltration and fibrosis in muscles, has been extensively used for DMD evaluations. PURPOSE: Notably, changes in muscle microstructures also result in acoustic attenuation, potentially serving as another crucial imaging biomarker for DMD. Expanding upon the reference frequency method (RFM), this study contributes to the field by introducing the robust RFM (RRFM) as a novel approach for ultrasound attenuation imaging in DMD. METHODS: The RRFM algorithm was developed using an iterative reweighted least squares technique. We conducted standard phantom measurements with a clinical ultrasound system equipped with a linear array transducer to assess the improvement in attenuation estimation bias by RRFM. Additionally, 161 DMD patients, included in both a validation dataset (n = 130) and a testing dataset (n = 31), underwent ultrasound scanning of the gastrocnemius for RRFM-based attenuation imaging. The diagnostic performances for ambulatory functions and discrimination between early and late ambulatory stages were evaluated and compared with those of QUS envelope statistics imaging (involving Nakagami distribution, homodyned K distribution, and entropy values) using the area under the receiver operating characteristic curve (AUROC). RESULTS: The results indicated that the RRFM method more closely matched the actual attenuation properties of the phantom, reducing measurement bias by 50% compared to conventional RFM. The AUROCs for RRFM-based attenuation imaging, used to discriminate between early and late ambulatory stages, were 0.88 and 0.92 for the validation and testing datasets, respectively. These performances significantly surpassed those of QUS envelope statistics imaging (p < 0.05). CONCLUSIONS: Ultrasound attenuation imaging employing RRFM may serve as a sensitive tool for evaluating the progression of ambulatory function deterioration, offering substantial potential for the health management and follow-up care of DMD patients.

Accuracy of controlled attenuation parameter for liver steatosis in patients at risk for metabolic dysfunction-associated steatotic liver disease using magnetic resonance imaging: a systematic review and meta-analysis.

Background: The controlled attenuation parameter (CAP) enables the noninvasive assessment of liver steatosis. We performed a systematic review and meta-analysis to evaluate the diagnostic accuracy of CAP for identifying liver steatosis in patients at risk for metabolic dysfunction-associated steatotic liver disease (MASLD), using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the reference standard. Methods: We searched Medline, Embase, Cochrane Library and gray literature sources up to March 2024. We defined MASLD as MRI-PDFF ≥5%. We also assessed the accuracy of CAP for identifying patients with MRI-PDFF ≥10%. We calculated pooled sensitivity and specificity estimates using hierarchical random-effects models. We assessed the risk of bias using the Quality Assessment of Diagnostic Accuracy Studies 2 tool, and the certainty in meta-analysis estimates using the Grading of Recommendations Assessment, Development and Evaluation framework. Results: We included 8 studies with 1116 participants. The prevalence of MASLD ranged from 65.2-93.9%. Pooled sensitivity and specificity of CAP for MRI-PDFF ≥5% were 0.84 (95% confidence interval [CI] 0.79-0.88) and 0.77 (95%CI 0.68-0.84), respectively, with an area under the receiver operating characteristic curve (AUROC) of 0.88. The pooled sensitivity and specificity for MRI-PDFF ≥10% were 0.83 (95%CI 0.80-0.87) and 0.72 (95%CI 0.59-0.82), with an AUROC of 0.85. The certainty in our estimates was low to very low because of the high risk of bias, inconsistency and imprecision. Conclusions: CAP has acceptable diagnostic accuracy for both MRI-PDFF ≥5% and MRI-PDFF ≥10%. Adequately powered and rigorously conducted diagnostic accuracy studies are warranted to establish the optimal CAP thresholds.

A novel hybrid LFC scheme for multi-area interconnected power systems considering coupling attenuation.

In this paper, a hybrid load frequency control (LFC) scheme is proposed for multi-area interconnected power systems to decouple the intricate double control objectives, by dividing all subareas into the responsible areas and the free areas. The LFC in the responsible area has the function of regulating both the local frequency and the tie-line power, while the control objective of the LFC in the free area is thus simplified to regulate the local frequency only. Then, addressing the complex network coupling and uncertain dynamics, an integrated LFC controller is proposed for the free areas, which consists of two parts, namely, the coupling attenuation baseline controller and the disturbance compensation controller. The coupling attenuation baseline controller satisfying the predefined bounded L2-Gain condition is derived based on the solution to a multi-player zero-sum differential game. Additionally, a novel generalized integral observer is designed to estimate the system's integrated disturbance, and the corresponding disturbance compensation controller is derived. After that, the ultimately uniformly bounded (UUB) stability of the integrated LFC controller combining baseline controller and disturbance compensation controller is proven rigorously. Finally, the performance superiority of the proposed hybrid LFC scheme is validated by the simulations in challenging operating modes.

In enzymatic reactions, the reverse reaction reduces product noise.

Enzymatic reactions are essential for most cellular reactions and ubiquitous in living organisms. In the present study, we explore the pivotal role of the reverse reaction in enzymatic reactions. It is a powerful noise-buffering motif. By SSA (stochastic simulation algorithm), a remarkable 32% reduction of product CV (coefficient of variation) was observed. To better understand the causes, we split the upstream noise. The product CV reduction is more than 35% for the noise inherited from the enzyme but merely 6%-21% for that from the substrate. It implies that the system applies different strategies to different upstream noises. We identified two leading causes responsible for noise attenuation. A cell is well designed to control its intracellular noise, and to acquire wisdom from nature is always enjoyable.

[Measurement and evaluation of personal attenuation rating before and after the training of the noise-exposed workers wearing foam earplugs].

Objective: To measure and compare the difference of personal attenuation rating (PAR) of the workers wearing foam earplugs before and after the training, and to evaluate the effect of ear protector wearing training on the noise protection. Methods: In February 2023, 94 workers exposed to noise in a machinery manufacturing factory were selected as subjects. The production noise in the workplace was measured and subjects were trained to wear earplugs. The PAR values of wearing 3M 1110 foam test earplugs were measured and recorded before and after the training by using the fit testing of hearing protection device. The differences between the actual PAR values with nominal values and the noise attenuation values in related standards were compared, and the protective effect of hearing protection device before and after training was evaluated. Results: The average age of the subjects was (36.76±11.48) years old, the average length of service was (16.34±11.64) years, and the average exposure time to noise was (15.67±11.64) years. The noise detection results of the subjects' posts were ranged from 80.1 to 94.3 dB (A). The results of subjects wore 3M 1110 foam test earplugs for fit testing showed that the binaural PAR value after training was (19.3±6.4) dB (A), which was significantly higher than that before training (11.1±7.4) dB (A) (t=13.31, P<0.001). After training, 11 people (11.70%) could reach the corrected noise reduction value (NRR value), 26 people (27.66%) could reach the standard of single noise reduction value (SNR value) ×0.6, and 84 people (89.36%) could reach the standard of (NRR-7) /2. The under protection rate of hearing protectors after training (7.45%) was significantly lower than that before training (45.74%), and the difference of different protection levels before and after training was statistically significant (χ(2)=40.83, P<0.001) . Conclusion: It is suggested that enterprises should use the fit testing instead of nominal value estimation to evaluate the noise reduction effect of hearing protection device. Special training on the selection and use of hearing protection device should be strengthened, so as to ensure that workers wear them correctly and improve the protective effect of hearing protection device.

Effect of Indo-Mediterranean diet versus calorie-restricted diet in children with non-alcoholic fatty liver disease: A pilot randomized control trial.

BACKGROUND: Dietary interventions and increased physical activity are the cornerstones for management of the paediatric non-alcoholic fatty liver disease (NAFLD). Though, no specific diet has been proven superior, Indo-Mediterranean diet (IMD) has shown promise in adult literature. Thus, we aimed to compare the effect of IMD and a standard calorie-restricted diet (CRD) in Indian overweight children and adolescents with biopsy-proven NAFLD. METHODS: Thirty-nine consecutive biopsy-proven NAFLD children between the ages of 8 and 18 years were randomized into either IMD or CRD for 180 days, and various parameters were evaluated at baseline and then after 180 days (NCT05073588). RESULTS: A total of 34 subjects (18 in IMD and 16 in CRD group) completed the study. There was a significantly higher decrease in controlled attenuation parameter (CAP) values (as a marker of hepatic steatosis; on transient elastography) (95% CI: 4.2-73.4, p = 0.042), weight (95% CI: 0.75-5.5, p = 0.046) and body mass index (BMI) (95% CI: 0.21-2.05, p = 0.014) (but not in Pediatric NAFLD Fibrosis Index or PNFI; as a marker of hepatic fibrosis) in IMD group compared to the CRD group. Liver stiffness measurement, serum cholesterol and low-density lipoprotein levels and HOMA-IR decreased only in the IMD group (p < 0.001). Our statistical model showed that delta-Weight was the only independent variable associated with delta-CAP. CONCLUSION: Both IMD and CRD can improve the various anthropometric, clinical, imaging and biochemical parameters but IMD was superior to CRD in terms of reducing CAP values and weight/BMI over 180 days in overweight/obese NAFLD children.