Changes In Relative Frequency Research Articles

Structural Health Monitoring of a High-Rise Building Using Ambient Noise Recordings and a Regional Earthquake Record

Abstract Resonance frequency and seismic-wave velocity monitoring are both important for structural health monitoring (SHM). However, the limited number of vibration sensors or seismometers in most buildings necessitates the study of the sensitivity of monitoring indicators to ensure effective monitoring while reducing data acquisition costs and processing time. This study compares the changes in resonance frequency and seismic-wave velocity under ambient noise and a regional seismic event. Resonance frequency is calculated by power spectral density, whereas seismic-wave velocity is estimated using impulse response function and moving-window cross-spectrum methods. The results indicate that relative resonance frequency changes are more suitable for overall SHM due to its higher sensitivity and lower instrument requirements. Moreover, the time–frequency analysis method provides higher resolution results in resonance frequency during seismic events, a precision that seismic velocity methods cannot achieve.

Performance improvement of predictive voltage control for interlinking converters of integrated microgrid

Voltage quality in Renewable Energy System may be harmed by varying power demand and fluctuating energy source outputs. The model predictive voltage (MPV) control approach is suggested in this study. The proposed control strategy enables appropriate power interactions between the AC and DC subgrids while sharing power fluctuations in a coordinated way. Both the AC and DC subgrids support each other in accordance with their normalized relative changes in AC frequency and DC voltage, respectively. A typical photovoltaic (PV) wind-battery-based hybrid AC/DC microgrid is modelled and investigated, and the usefulness of the proposed scheme is validated under the renewable energy variations and load perturbations. MATLAB/Simulink has validated the efficacy of the suggested strategy. A set of comparative tests was conducted between conventional Proportional-Integral (PI) control, Sliding Mode Control (SMC) strategies, and a novel Model Predictive Voltage Control (MPV) approach under diverse conditions. The aim was to comprehensively assess the advantages of the proposed MPV method. Results demonstrate that, in contrast to traditional PI and SMC control strategies, the MPV technique exhibits distinct benefits in terms of superior control performance and achieves exceptionally low Total Harmonic Distortion (THD) values. Ultimately, the proposed solution not only raises the performance standard but also ensures the stable operation of the Renewable Energy System (RES).

Pedestrian injuries in the United States: Shifting injury patterns with the introduction of pedestrian protection into the passenger vehicle fleet

Objective Between 2010 and 2020, an annual average of more than 70,000 pedestrians were injured in U.S. motor vehicle crashes. Pedestrian fatalities increased steadily over that period, outpacing increases in vehicle occupant fatalities. Strategies for reducing pedestrian injuries include pedestrian crash prevention and improved vehicle design for protection of pedestrians in the crashes that cannot be prevented. This study focuses on understanding trends in injuries sustained in U.S. pedestrian crashes to inform continuing efforts to improve pedestrian crash protection in passenger vehicles. Methods More than 160,000 adult pedestrians injured in motor vehicle crashes who were admitted to U.S. trauma centers between 2007 and 2016 were drawn from the National Trauma Data Bank (NTDB) Research Data Sets. The injuries in those cases were used to explore the shifting patterns of pedestrian injuries. Results The proportion of pedestrians with thorax injuries increased 3.0 percentage points to 30.7% of trauma center–admitted NTDB pedestrian cases over the 10 years studied, and the proportion with pelvis/hip injuries increased to 21.2%. The proportion of cases with head injuries fell to 48.6%, and the percentage of pedestrians with lower extremity injury (44%) did not change significantly over the 10 year period. Assessment of possible reasons for the shifts suggested that increasing numbers of sport utility vehicles, population increases among the oldest age groups, and improvements in pedestrian protection in U.S. passenger vehicles likely contributed to, but did not completely account for, the relative changes in injury frequency in each body region. Conclusions More important than the reasons for the shifts in the relative frequency of injury to each body region are the conclusions that can be drawn regarding priorities for pedestrian protection research. Though head/face and lower extremity injuries remained the most frequently injured body regions in adult pedestrians admitted to NTDB trauma centers, the relative frequency of thorax and pelvis/hip injuries increased steadily, underlining the increasing importance of pedestrian protection research on these body regions.

Relative frequencies of perovskite solar cells strengthened by composite materials: Application of deep neural networks for solving the vibration problem

Perovskite solar cells have shown competitive power conversion efficiencies (PCE) with the potential for better performance when compared to the most widely used photovoltaic technology. Perovskites may deteriorate when exposed for an extended amount of time to light, heat, or electrical current, as well as when they interact with moisture and oxygen. To increase stability, researchers are examining deterioration in both the perovskite material itself and the surrounding device layers. Cell durability has to be increased in order to produce perovskite solar goods for sale. Improved cell durability is critical for the development of commercial perovskite solar products. So, improving the dynamic properties of this kind of green energy device is a key issue in engineering. In the current report, the stability zone and relative frequency change of the perovskite solar cells reinforced by three-dimensional functionally graded material (3D-FGM) as the last layer is presented. For exact modeling of the perovskite solar cell structure due to its size (micro size), it is crucial to take the size effect into account. Modified couple stress theory (MCST) as a size-dependent theory for micro-scale systems with curvature derivate parameters is offered. Once the study’s findings have mastered the mathematical discoveries, they are instructed to produce the machine learning technique’s outputs. In actuality, the fast-converging numerical approach is used to derive the characteristics of the design points. The momentum-based optimizer is used to find the optimal values of the parameters influencing how the fully connected neural network functions. The method used in this research is efficient since it quickly and properly trains the multi-layered network. The funding now available may be used to promote future research on the importance of the dynamic stability of perovskite solar cells employing 3D-FG material as the constructed layer.

A study on hydrological responses of the Fuhe River Basin to combined effects of land use and climate change

Study regionThe Fuhe River Basin in Jiangxi Province, China. Study focusGlobal climate change and intensified human activities are making the hydrological processes at Fuhe River Basin experiencing dramatic changes. Although some studies have investigated their individual impacts on basin-scale water resources, their combined effects on hydrology have received little attention. In this study, future scenarios were constructed for three future periods, based on five global climate model outputs (GCMs) from the Coupled Model Intercomparison Project Phase 6 (CMIP6) and a dataset of future land use projections under three shared socioeconomic pathways and representative concentration pathways (SSP-RCPs). Then, the Soil and Water Assessment Tool (SWAT) model was used to assess the relative changes in water balance components and extreme flow frequency under these developed scenarios. Furthermore, the hydrological response assessment methodology was improved from the original multiscenario ensemble flow forecast (MESF) framework, which not only strengthens the connection between climate and land use input changes but also adds more assessment items. New hydrological insights for the regionThe flow at the outlet of Fuhe River Basin is expected to increase by approximately 27.1%− 30.2%, 24.7–39.0% and 35.5%− 43.5% in the 2030 s, 2060 s and 2090 s, respectively. Water availability will increase significantly in February, August and October and decrease in November and December. To the end of 21st century, surface runoff will have more than 100% increase. Future floods and droughts will be more frequent and severe under SSP5–8.5.

Headache Frequency and Pain Severity Following a Nerve Stimulator Implant for Chronic Migraine: A Systematic Review and Meta-Analysis

Migraines affect approximately one billion individuals worldwide. Implanted nerve stimulator devices can provide relief to some individuals who have chronic migraines refractory to other treatments. This study defines the change in headache pain severity and headache frequency following implanted nerve stimulator treatment in chronic migraineurs. A PRISMA-compliant systematic review of six databases was performed to identify all clinical trials treating at least 10 chronic migraineurs with an implanted nerve stimulator. Inverse variance random effects meta-analyses were performed to define the relative change in headache pain severity and headache frequency as compared to baseline. Nine studies met criteria, including 5 randomized controlled clinical trials and 4 uncontrolled clinical trials, and treated 559 individuals. Among studies that reported gender, 306 females and 154 males were treated. Mean patient ages ranged from 45 to 50 years. All included studies targeted the greater occipital nerve with an implanted nerve stimulator. Implanted nerve stimulator treatment reduced pain severity at 1 month by 36.42% (95%-CI: 28.35-44.49, I<sup>2</sup> = 55%) and 3 months by 50.04% (95%-CI: 39.67-60.42%, I<sup>2</sup> = 26%). Implanted nerve stimulators reduced headache frequency by 49.86% (95%-CI: 31.49-68.23, I<sup>2</sup> = 92%) at 1 to 3 months and 27.43% (95%-CI: 17.68-37.18, I<sup>2</sup> = 63%) at 6 to 97 months. Implanted nerve stimulator devices provide clinically and statistically significant improvements in headache severity and frequency in individuals with chronic migraines.

Intake of low dietary fiber changes microbiota composition and reduces IL-10 production from small intestinal T cells

Abstract Regulatory immune responses are crucial for intestinal homeostasis against stimuli like diet and microbiota. The microbiota influences the regulatory immune response by inducing colonic Foxp3+ regulatory T cells and other lymphocytes by metabolizing diet-derived products. For example, fiber-fermenting microbiota process fermentable fiber into metabolites like short-chain-fatty-acids (SCFA) and help activate IL-10-producing T cells. However, studies showed that high-fat (low-fiber) diet alters the abundance of Treg-inducing commensal bacteria promoting intestinal inflammation. Previous studies in our lab showed that low fermentable fiber affects the generation of many intestinal T cells, especially intraepithelial CD4+CD8aa+ T cells (DP IELs) and CD8aa IELs. However, it is still uncertain how dietary fiber affects small intestinal T cell function, including IL-10 production. To address this, we fed IL-10-GFP reporter mice with a regular chow diet or an isocaloric isonitrogenous diet that replaced fiber with non-fermentable fiber (LFF). After four weeks, the lymphocytes and microbiota from the small intestine were analyzed. Our preliminary findings show that IL-10 mRNA expression and IL-10-GFP production from intestinal lymphocytes was lower in mice fed LFF diet when compared to the control. Moreover, 16S RNA sequencing of intestinal contents showed changes in relative frequencies of several OTUs between diets. These results suggests that certain bacterial species affected by the diet could be significant in promoting IL-10 production by small intestinal T cells. Further studies will seek to understand how fiber plays a role in orchestrating the host-microbiota interactions to maintain intestinal tolerance. These studies were conducted at Emory University and funded by the following NIH grants: 1R01DK129950-01 (NIDDK-NIH from LCB); 5T32AI106699-08 (NIDDK-NIH from Antimicrobial Resistance and Therapeutic Discovery Training Program)

In-Situ Single Crystal XRD and Raman Spectra Investigation of (Mg, Fe, Mn)CO3 at Various Temperatures

The in-situ X-ray diffraction (XRD) and Raman spectra of synthetic (Mg, Fe, Mn)CO3 single crystals for (Mg0.37Fe0.31Mn0.32)CO3, (Mg0.49Fe0.51)CO3, (Fe0.47Mn0.53)CO3, and (Mg0.50Mn0.50)CO3 were investigated up to 871 K. Lattice parameters and the volumetric thermal expansion coefficients were achieved, demonstrating an inherent anisotropy of c/a near to 3.0. The Raman spectra of our intermediate components all exhibit a negative temperature dependence similar to that of the end members. The temperature dependence of the external modes T, L, anti-symmetric stretching mode ν3, and out-of-plane bending mode 2ν2 is generally more prominent than the in-plane bending mode ν4 and symmetric stretching mode ν1 except for siderite FeCO3. Combining thermal expansion coefficients αV with the relative changes in frequency δνi/δT of Raman spectra, the average thermodynamic Grüneisen parameters (γth) for (Mg0.37Fe0.31Mn0.32)CO3, (Fe0.47Mn0.53)CO3, (Mg0.50Mn0.50)CO3, MgCO3, and MnCO3 were obtained as 1.18, 1.36, 1.34, 1.13, and 1.53, respectively. The relationship between Fe2+ and Mn2+ contents and γth illustrates that the concentration of Fe2+ causes a negative effect while the concentration of Mn2+ causes a positive effect on γth. These results could provide a reference for the contribution of Fe2+ and Mn2+ on the structural and thermodynamic properties of (Mg, Fe, Mn)CO3 carbonates.

2114. Invasive fusariosis in the era of mold active azoles and molecular targeted chemotherapy: Increasing incidence and lack of improved outcomes

Abstract Background Invasive fusariosis (IF) is an uncommon opportunistic mold infection primarily affecting patients (pts) with leukemia and allogeneic hematopoietic cell transplant (HSCT). Historically, IF had poor outcome when there is lack of recovery from immunosuppression. However, IF incidence and outcome in the in the era of new mold-active triazoles and leukemia regimens that incorporate molecularly targeted drugs is unknown. Methods We retrospectively studied the incidence, risk factors, clinical features, and outcome of microbiologically documented IF (revised EORTC/MSG criteria) in pts with leukemia at MD Anderson Cancer Center in the last 12 years (June 2009-October 2021). The independent risk factors for 42-day (d) mortality from IF diagnosis were assessed by a binary multivariable logistic regression model. Annual incidence density (1998-2021) was estimated using Poisson regression analysis. Results Among 140 IF pts (114 proven, 26 probable), 100 (71%) had pneumonia, 88 (63%) disseminated infection, and 32 (23%) sinusitis, with no apparent changes in relative frequency over the years. 124 pts (89%) had neutropenia (ANC < 500) at IF diagnosis, 118 (84%) had relapsed/refractory (R/R) leukemia, and 43 (31%) had prior HSCT. 19% (18/97 pts) of IF pts had positive serum galactomannan and 55% had coinfections. In the last 5 years of the study, 45/58 IF cases (78%) were breakthrough infections to mold active triazoles (12 voriconazole, 25 posaconazole, 8 isavuconazole). 74 (53%) out of the 140 IF pts died by d42. Only 6 pts (9%) had neutrophil recovery at time of death compared to 47 (64%) who survived until day 42 (P < 0.001). Neutrophil recovery (aOR 0.04, 95% CI 0.01-0.14), SOFA score (aOR 1.91 per point, 95% CI 1.47-2.50), and pneumonia (aOR 3.28, 95% CI 1.11-9.70) were independent predictors of 42-d mortality. Since 1998, the incidence density of IF continuously increased (P = 0.006) at an annual ratio of 1.05 (95% CI 1.02-1.07, Figure 1). Figure 1Incidence density of invasive fusariosis (per 100,000 patient-days) in leukemia patients between 1998 and 2021 Conclusion Over the past 23 years, IF incidence has been increasing. IF is predominantly seen in pts with R/R acute leukemia and increasingly seen as a breakthrough infection to mold-active triazoles. Even in contemporary pt cohorts, IF has high mortality in the setting of persistent myelosuppression. Disclosures Russell E. Lewis, PharmD, Air: Advisor/Consultant|Cidara: Advisor/Consultant|F2G: Advisor/Consultant|Gilead: Advisor/Consultant|Merck & Co, Inc: Grant/Research Support|Synexis: Advisor/Consultant Dimiitrios P. Kontoyiannis, MD, ScD, PhD (hon), AbbVie: Advisor/Consultant|Astellas Pharma: Advisor/Consultant|Astellas Pharma: Grant/Research Support|Astellas Pharma: Honoraria|Cidara Therapeutics: Advisor/Consultant|Gilead Sciences: Advisor/Consultant|Gilead Sciences: Grant/Research Support|Gilead Sciences: Honoraria|Merck: Advisor/Consultant.

Projecting multi-attribute flood regime changes for the Yangtze River basin

Climate change is altering flood risk globally. The nature of those alterations varies locally, creating the need for regional assessments to inform flood-risk management and planning. This study projects future changes in flood regime in the Yangtze River basin. To characterize flood regimes, we use a multi-attribute approach that measures the relative change in flood magnitude, timing, frequency, and duration between historical and future periods. We use climate projections from the Coupled Model Intercomparison Project Phase 6 (CMIP6) to force the Soil and Water Assessment Tool (SWAT), and generate daily streamflow projections along the Yangtze River network for two Shared Socioeconomic Pathways (SSPs), SSP2-4.5 and SSP5-8.5. We use seasonal maxima, annual maxima, and peaks-over-threshold to determine the different flood attributes. Results show that downscaled CMIP6 precipitation and near-surface temperature are both projected to increase substantially in the future, with a consequent surge in floods across the basin. In the far future (years 2061–2100), under SSP5-8.5, average annual flood magnitude, timing, frequency, and duration are projected to increase 66.6 %, arrive 1.9 days earlier, increase 27.5 %, and prolong 19.1 days, respectively. Projected changes in flood attributes at annual timescale are generally higher in the basin's northern tributaries than in the southern ones. Changes in flood magnitude and frequency tend to resemble each other, whereas flood timing and duration exhibit distinct change patterns. Our multi-attribute approach to flood regime characterization provides a systematic way for translating raw CMIP6 projections into informative future flood projections. This approach can help inform flood-risk planning and improve the reliability of climate change impact assessment.

Damage localization in beams based on the analysis of modal parameters

This paper presents a two-step method for damage localization in beams by combining natural frequencies and mode shapes. The general locations of the damage are first identified from an indicator developed using relative natural frequency change (RNFC) curves and the values of RNFCs. A curvature-mode-shape-based method is then utilized to determine the specific location of the damage in the second step. The proposed two-step method is verified by detecting damage in a simulated simply-supported beam. The identified damage location agrees well with the actual damage location. A strategy for fast and accurate damage localization based on general localization using natural frequencies and specific localization using mode shapes is the main novelty of the paper.

Spatiotemporal characteristics of lower back muscle fatigue during a ten minutes endurance test at 50% upper body weight in healthy inactive, endurance, and strength trained subjects.

In modern developed societies, heavy physical demands are decreasing and getting replaced by longer periods of static, low-exertion activities such as sitting or standing. To counteract this lack of physical activity, more and more people are engaging in physical activity through exercise and training. Virtually opposite training modalities are endurance and strength. We asked if back muscle endurance capacity is influenced by training mode. 38 healthy male subjects (age range 19–31 years, mean age 22.6 years) were investigated: sedentary (Control, n = 12), endurance trained (ET, n = 13), and strength trained participants (ST, n = 13). They underwent a ten-minutes isometric extension task at 50% of their upper body weight. Surface EMG was measured in the low-back region utilizing quadratic 4*4 monopolar electrode montages per side. Relative amplitude and mean frequency changes were analysed with respect to electrode position and group during the endurance task. Eight ST subjects failed to complete the endurance task. Relative amplitude and frequency changes were largest in the ST group, followed by Control and ET groups (amplitude: F 6.389, p 0.004, frequency: F 11.741, p<0.001). Further, independent of group largest amplitude increase was observed for the most upper and laterally positioned electrodes. Mean frequency changes showed no systematic spatial distribution pattern. Although, in the light of an aging population, strength training has its merits our results question the functional suitability of frequent and isolated high-impact strength training for everyday endurance requirements like doing the dishes. Fatigue related amplitude elevations are systematically distributed in the back region, showing least fatigue signs for the most caudal and medial, i.e. the lumbar paravertebral region.

Warp-based edge feature reinforcement network for medical image segmentation.

Rapid and accurate segmentation of medical images can provide important guidance in the early stages of life-threatening diseases. However, fuzzy edges and high similarity with the background in images usually cause undersegmentation or oversegmentation. To solve these problems. We propose a novel edge features-reinforcement (EFR) module that uses relative frequency changes before and after warping images to extract edge information. Then, the EFR module leverages deep features to guide shallow features to produce a band-shaped edge attention map for reinforcing the edge region of all channels. We also propose a multiscale context exploration (MCE) module to fuse multiscale features and to extract channel and spatial correlations, which allows a model to focus on the parts that contribute most to the final segmentation. We construct EFR-Net by embedding EFR and MCE modules on the encoder-decoder architecture. We verify EFR-Net's performance with four medical datasets: retinal vessel segmentation dataset DRIVE, endoscopic polyp segmentation dataset CVC-ClinicDB, dermoscopic image dataset ISIC2018, and aortic true lumen dataset Aorta-computed tomography (CT). The proposed model achieves Dice similarity coefficients (DSCs) of 81.61%, 92.87%, 89.87%, and 96.98% on DRIVE, CVC-ClinicDB, ISIC2018, and Aorta-CT, respectively, which are better than those of current mainstream methods. In particular, the DSC of polyp segmentation increased by 3.87%. Through quantitative and qualitative research, our method is determined to surpass current mainstream segmentation methods, and EFR modules can effectively improve the edge prediction effect of color images and CT images. The proposed modules are easily embedded in other encoder-decoder architectures, which has the potential to be applied and expanded.

Investigation of the incidence trend of follicular lymphoma from 2008 to 2017 in Taiwan and the United States using population-based data.

The incidence of follicular lymphoma (FL) in Taiwan has not been well investigated since its inclusion as a histological subtype in the Taiwan Cancer Registry in 2008. The purpose of this study was to describe the incidence patterns of FL in Taiwan and compare the trends with those in other racial groups in the United States. We conducted an epidemiological study using population-based data from the Taiwan Cancer Registry, Ministry of Health and Welfare, and the 18 Surveillance, Epidemiology, and End Results (SEER) registries to evaluate the FL incidence from 2008 to 2017. We calculated the annual percent change (APC) to describe the trends in the incidence of FL in subpopulations defined by race and sex over time. The annual age-adjusted incidence rate of FL in Taiwan increased significantly from 0.59 per 100,000 persons in 2008 to 0.82 per 100,000 persons in 2017, with an APC of 3.2. By contrast, the incidence rate in whites in the United States during the same period decreased from 3.42 to 2.74 per 100,000 persons, with an APC of -2.1. We found no significant change for the blacks (APC, -1.5%), Hispanics (APC, -0.7%), and Asians or Pacific Islanders (APC, +0.7%). The temporal trend was similar between the males and females. The relative frequency of FL among the incident non-Hodgkin lymphoma (NHL) cases also increased significantly in Taiwan from 7.64% in 2008 to 11.11% in 2017 (APC = 3.8). The relative frequency of FL among the incident NHL cases in the whites decreased from 2008 to 2012 (APC, -3.8%) and then stabilized after 2012 (APC, -0.2%). By contrast, little change in relative frequency of FL among the incident NHL cases was observed in the blacks, Hispanics, and APIs between 2008 and 2017. We found increases in the incidence of FL and the relative frequency of FL among the incident NHL cases in both males and females in Taiwan from 2008 to 2017. The FL incidence rates were unchanged for all races and sex groups in the United States, except for the decreases in the whites.

Phylogenetic inference of changes in amino acid propensities with single-position resolution.

Fitness conferred by the same allele may differ between genotypes and environments, and these differences shape variation and evolution. Changes in amino acid propensities at protein sites over the course of evolution have been inferred from sequence alignments statistically, but the existing methods are data-intensive and aggregate multiple sites. Here, we develop an approach to detect individual amino acids that confer different fitness in different groups of species from combined sequence and phylogenetic data. Using the fact that the probability of a substitution to an amino acid depends on its fitness, our method looks for amino acids such that substitutions to them occur more frequently in one group of lineages than in another. We validate our method using simulated evolution of a protein site under different scenarios and show that it has high specificity for a wide range of assumptions regarding the underlying changes in selection, while its sensitivity differs between scenarios. We apply our method to the env gene of two HIV-1 subtypes, A and B, and to the HA gene of two influenza A subtypes, H1 and H3, and show that the inferred fitness changes are consistent with the fitness differences observed in deep mutational scanning experiments. We find that changes in relative fitness of different amino acid variants within a site do not always trigger episodes of positive selection and therefore may not result in an overall increase in the frequency of substitutions, but can still be detected from changes in relative frequencies of different substitutions.

Assessment of auditory processing in childhood dysphonia

IntroductionClinical experience shows that children with functional dysphonia often present disorders that are associated with abnormal auditory and emotional development. These children also struggle with voice therapy, perhaps because of difficulties with auditory control during speech. It has been hypothesized that difficulties in auditory processing in children may be an important factor in the pathogenesis of childhood dysphonia. ObjectiveThe study aimed to assess selected auditory functions in children with hyperfunctional dysphonia. Materials and methodThe study group consisted of 331 children aged from 7 to 12 years suffering from hyperfunctional dysphonia. The control group consisted of 213 children aged 7–12 years. All patients underwent ENT and phoniatric examination. All children underwent two standardized psychoacoustic tests: the Frequency Pattern Test (FPT) and the Duration Pattern Test (DPT). ResultsIn the examined material, 223 children had edematous vocal fold nodules. The largest statistically significant differences were seen in the acoustic parameters describing relative frequency changes. FPT and DPT showed statistically significant differences in children with hyperfunctional dysphonia compared to the control group. At all ages the percentage of correctly identified tone sequences was significantly lower in children with dysphonia. ConclusionChildren with hyperfunctional dysphonia have difficulties in judging the pitch and duration of auditory stimuli. Difficulties in auditory processing appear to be important in the pathomechanism of functional voice disorders. Impaired hearing processes in children with hyperfunctional dysphonia can make it difficult to obtain positive and lasting effects from voice therapy.

Efficacy and Safety of Pregabalin for Muscle Cramps in Liver Cirrhosis: A Double-Blind Randomized Controlled Trial.

BackgroundMuscle cramp is possibly related to peripheral nerve hyperexcitability (PNH), and one of the most debilitating symptoms frequently encountered in patients with liver cirrhosis. We investigated whether pregabalin, a gamma-aminobutyric acid analogue, can suppress neuronal excitability and reduce muscle cramps in cirrhotic patients.MethodsWe conducted a randomized, double-blind, placebo-controlled trial in which study participants with cirrhosis from a single tertiary center were enrolled. Primary endpoint was the relative change in cramp frequency from the run-in to standard dose treatment phase (4 weeks per each). Secondary endpoints included the responder rate, and the changes in cramp frequency during sleep, pain intensity, health-related quality of life (Liver Disease Quality of Life Instrument, Short Form-36) and electrophysiological measures of PNH.ResultsThis study was terminated early because of insufficient accrual. 80% (n = 56) of the target number of participants (n = 70) were randomized to pregabalin (n = 29) or placebo (n = 27). Median baseline frequency of muscle cramps (interquartile range) was 5.8 (3.5–10) per week in the pregabalin group and 6.5 (4.0–10) in the placebo group (P = 0.970). The primary analysis showed a significant reduction in cramp frequency with pregabalin compared to placebo (−36% vs. 4.5% for the percentage change, P = 0.010). Secondary outcomes did not differ significantly between the two groups. Adverse effects with pregabalin were mainly dizziness and lethargy.ConclusionWith multiple problems emerging from premature termination in mind, the results suggested an acceptable safety profile and favorable effect of pregabalin in reducing muscle cramps compared to placebo in cirrhotic patients.Trial RegistrationClinicalTrials.gov Identifier: NCT01271660

A two-step method for additional mass identification in beam structures by measurements of natural frequencies and guided waves

This paper presents a two-step method for the identification of additional masses in beam structures. In the first step, relative natural frequency change (RNFC) curves are developed as an indicator for identifying the possible locations of additional masses at the global level. The RNFC curves based method allows detection of possible mass locations using natural frequencies alone and as such is a significant improvement over the state of the art. To further identify the precise locations of the masses, guided wavefield imaging is used for local mass detection in the second step. The two-step method is successfully applied for the precise localization of additional masses on a simply-supported beam. The paper firstly shows that additional mass-induced RNFC curves are different from those caused by cracks in beams. As a result, a theoretical formulation and validation of additional mass identification is needed and is the main novelty of the paper.

Relationship Between Perceived Exercise Intensity And Natural Killer Cell Mobilization After Exercise

The mobilization of lymphocyte subsets into and out of peripheral blood after dynamic exercise is well-characterized. While the magnitude of this effect has been shown to relate to objective measures of exercise intensity, the role of perceived intensity of the exercise bout is less understood. PURPOSE: Determine if the change in frequency of peripheral blood lymphocytes following acute dynamic exercise is associated with ratings of perceived exertion (RPE). METHODS: 18 physically active adults (8 women, aged 27.7 ± 4.4 years) cycled on a stationary bicycle 30 min at a power sufficient to elicit 80% of their age predicted maximum heart rate (HR). Heart rate and RPE (Borg 6-20 scale) was recorded each minute. Venous blood sampled pre- and post-exercise was analyzed by flow cytometry, and the relative change in lymphocyte subset frequency was calculated post-exercise relative to pre-exercise. The relationship between change in lymphocyte subset frequency with RPE in the final minute of exercise (RPE-end), or HR in final minute of exercise (HR-end), was assessed by linear regression. RESULTS: RPE-end significantly predicted the change in NK-cell frequency post-exercise, where RPE-end was higher in those displaying a greater mobilization (b = 40.41, SE = 17.28, p = .034, R2 = .267). Likewise, RPE-end predicted the increase in cytotoxic CD56dim NK-cells (b = 43.81, SE = 18.73, p = .034, R2 = .267). Analyzing subsets of CD56dim NK-cells differentiated by expression of inhibitory NKG2A and killer cell immunoglobulin-like receptor CD158b revealed RPE-end predicted the change in low- (b = 37.26, SE = 15.77, p = .032, R2 = .271), medium- (b = 43.03, SE = 18.41, p = .034, R2 = .267), and high-differentiated (b = 52.08, SE = 21.78, p = .030, R2 = .276) subsets. RPE-end did not significantly predict change in CD4 or CD8 T-cell subsets. HR-end did not significantly predict change in frequency of any lymphocyte subset. CONCLUSIONS: End of exercise RPE, but not HR, significantly predicted changes in the frequency of NK-cells in peripheral blood post-exercise. Although the current results are limited by the small sample, they suggest a role for the perception of exercise intensity in predicting immune responses to exercise.

Coral microbiome changes over the day–night cycle

Coral-associated microbiomes play important roles in host health and metabolism. It is therefore critical to understand the factors that shape microbiome taxonomic composition and function. Little is known about the stability of coral microbiomes over hourly fluctuations in environmental conditions. For parameters such as temperature and pH, the magnitude of day–night fluctuations can exceed those observed in mean values over seasons, especially on shallow reefs. Such short-term heterogeneity can affect longer term trends, possibly by influencing the extent to which corals acclimate to stress and increase resilience. This study examined diel dynamics of microbiomes (Bacteria and Archaea) in three species of stony coral (Porites lutea, Porites cylindrica, and Pocillopora damicornis) from a shallow reef in Mo’orea (French Polynesia). We assessed microbiome composition and relative transcriptional activity by analyzing 16S rRNA gene and transcript sequences from six timepoints over 48 h for each species. Both the composition and transcription of microbiome members changed significantly over the diel cycle. Most changes did not exhibit clear diel periodicity but were instead stochastic, a pattern potentially influenced also by microspatial variation within a coral colony. However, a subset of taxa, notably the dinoflagellate-associated bacterium Porticoccus and bacteria of the ubiquitous coral-associated Endozoicomonas genus, exhibited cyclic changes in relative frequency over the 2 d sampling period in the DNA dataset of Porites lutea. These patterns raise the possibility that ecological functions of the microbiome may vary substantially over hourly timescales, notably between day and night. Further studies are needed to compare temporal change in the coral microbiome with that due to other factors, such as spatial distance within and among colonies.