Effects Of Temporal Changes Research Articles

The importance of considering both acoustic and non-acoustic factors in mitigating the effects of aircraft noise on residents' well-being

This study examines the effect of temporal changes in aircraft noise exposure in Vietnam, focusing on the influence of non-acoustic factors. Using data from surveys conducted around Tan Son Nhat Airport (TSN) and Noi Bai Airport (NB), the study explores changes in noise exposure levels, evaluates the applicability of existing regulations, and assesses the impact of non-acoustic factors. Surveys conducted around NB between 2014 and 2018 examined operational changes, while those around TSN investigated the impact of the COVID-19 pandemic between 2019 and 2023. Findings suggest that non-acoustic factors significantly shape community responses to noise. This study underscores the importance of implementing comprehensive noise regulation policies that consider both acoustic and non-acoustic factors in mitigating aircraft noise impacts on residents' well-being, particularly in emerging and developing countries.

Effects of spatial and temporal crop changes on bird diversity in peri‑urban agricultural lands

Numerous studies have investigated bird diversity-environment relationships in agricultural landscapes. While many studies have emphasized the importance of natural/semi-natural elements and their diversity within or surrounding farmlands, it remains unclear how crop diversity impacts birds. There is also a significant gap in our knowledge regarding the effects of temporal changes in crop composition on bird diversity. Using small farmlands in a sub-tropical city of China, we examined how spatial and temporal variation of crops and other local farmland features was linked to species diversity of birds and their traits. In small peri‑urban agricultural areas of Guangzhou, we collected bird and crop/non-crop data approximately bimonthly from December 2021 to October 2022. Overall crop diversity and seasonal crop changes were indexed by alpha diversity (Shannon-Wiener index) and beta diversity, respectively. Both alpha and beta crop diversities were positively associated with Shannon-Wiener diversity of birds. Alpha crop diversity also tended to have a positive impact on species richness. Percent cover of woody vegetation showed a positive effect on all three bird diversity indices, i.e., species richness, Shannon-Wiener diversity, and evenness. Percent cover of rice affected species richness positively and evenness negatively, whereas the effects of percent cover of corn were the opposite. In a fourth-corner analysis, the abundance of plant/seed-eating birds was negatively associated with alpha crop diversity, whereas the abundance of ground-foraging birds was positively associated with beta crop diversity. These patterns indicate that seasonally dynamic crop changes as well as local crop diversity can influence bird diversity and traits in small farmlands. They also suggest that natural/semi-natural woody vegetation, such as trees and shrubs, play a critical role in enhancing species diversity of birds in farmlands dominated by herbaceous edible crops.

Analysis of the Effect of Temporal Changes on the Coolant Viscosity of the Pendinggin System on Motorcycles

A combustion motor is a machine that converts from chemical energy to motion energy, where in the working system of a combustion motor produces power or engine rotation which is produced from the process of combustion in the combustion chamber (cylinder). In addition to producing power and rotation, it also produces heat (thermal) as a result of the combustion process. Excessive heat generated by the combustion process can also cause problems if not overcome properly, can cause overheating. Therefore, a good cooling system such as radiator coolant is needed, in the fluid cooling system there is viscositic (viscosity of the substance) which can affect the absorption of heat. The following are the test results at temperatures of 27.8oC (0.35dpa.s), 70oC (0.275dpa.s), 90oC (0.25dpa.s). If the viscosity value is low, then in the flow rate the faster the heat absorption and heat transfer will be more effective, while if the viscosity value is high, then in the flow rate the slower the heat absorption and heat transfer process becomes ineffective.

Preconception depression reduces fertility: a couple-based prospective preconception cohort.

Is preconception depression associated with time to pregnancy (TTP) and infertility? Couples with preconception depression needed a longer time to become pregnant and exhibited an increased risk of infertility. Preconception depression in women contributes to impaired fertility in clinical populations. However, evidence from the general population-especially based on couples-is relatively scant. A couple-based prospective preconception cohort study was performed in 16 premarital examination centers between April 2019 and June 2021. The final analysis included 16521 couples who tried to conceive for ≤6 months at enrollment. Patients with infertility were defined as those with a TTP ≥12 months and those who conceived through ART. Couples' depression was assessed using the Patient Health Questionnaire-9 at baseline. Reproductive outcomes were obtained via telephone at 6 and 12 months after enrollment. Fertility odds ratios (FORs) and infertility risk ratios (RRs) in different preconception depression groups were analyzed using the Cox proportional-hazard models and logistic regression, respectively. Of the 16 521 couples analyzed, 10834 (65.6%) and 746 (4.5%) couples achieved pregnancy within the first 6 months and between the 6th and 12th months, respectively. The median (P25, P75) TTP was 3.0 (2.0, 6.0) months. The infertility rate was 13.01%. After adjusting for potential confounders, in the individual-specific analyses, we found that preconception depression in women was significantly related to reduced odds of fertility (FOR = 0.947, 95% CI: 0.908-0.988), and preconception depression in either men or women was associated with an increased risk of infertility (women: RR = 1.212, 95% CI: 1.076-1.366; men: RR = 1.214, 95% CI: 1.068-1.381); in the couple-based analyses, we found that-compared to couples where neither partner had depression-the couples where both partners had depression exhibited reduced fertility (adjusted FOR = 0.904, 95% CI: 0.838-0.975). The risk of infertility in the group where only the woman had depression and both partners had depression increased by 17.8% (RR = 1.178, 95% CI: 1.026-1.353) and 46.9% (RR = 1.469, 95% CI: 1.203-1.793), respectively. Reporting and recall bias were unavoidable in this large epidemiological study. Some residual confounding factors-such as the use of anti-depressants and other medications, sexual habits, and prior depressive and anxiety symptoms-remain unaddressed. We used a cut-off score of 5 to define depression, which is lower than prior studies. Finally, we assessed depression only at baseline, therefore we could not detect effects of temporal changes in depression on fertility. This couple-based study indicated that preconception depression in individuals and couples negatively impacts couples' fertility. Early detection and intervention of depression to improve fertility should focus on both sexes. This work was supported by grants from the National Natural Science Foundation of China (No. 82273638) and the National Key Research and Development Program of China (No. 2018YFC1004201). All authors declare no conflicts of interest. N/A.

HiPSC-CM electrophysiology: impact of temporal changes and study parameters on experimental reproducibility.

Human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are frequently used for preclinical cardiotoxicity testing and remain an important tool for confirming model-based predictions of drug effects in accordance with the comprehensive in vitro proarrhythmia assay (CiPA). Despite the considerable benefits hiPSC-CMs provide, concerns surrounding experimental reproducibility have emerged. We investigated the effects of temporal changes and experimental parameters on hiPSC-CM electrophysiology. iCell cardiomyocytes2 were cultured and biosignals were acquired using a microelectrode array (MEA) system (2-14 days). Continuous recordings revealed a 22.6% increase in the beating rate and 7.7% decrease in the field potential duration (FPD) during a 20-min equilibration period. Location-specific differences across a multiwell plate were also observed, with iCell cardiomyocytes2 in the outer rows beating 8.8 beats/min faster than the inner rows. Cardiac endpoints were also impacted by cell culture duration; from 2 to 14 days, the beating rate decreased (-12.7 beats/min), FPD lengthened (+257 ms), and spike amplitude increased (+3.3 mV). Cell culture duration (4-10 days) also impacted cardiomyocyte drug responsiveness (E-4031, nifedipine, isoproterenol). qRT-PCR results suggest that daily variations in cardiac metrics may be linked to the continued maturation of hiPSC-CMs in culture (2-30 days). Daily experiments were also repeated using a second cell line (Cor.4U). Collectively, our study highlights multiple sources of variability to consider and address when performing hiPSC-CM MEA studies. To improve reproducibility and data interpretation, MEA-based studies should establish a standardized protocol and report key experimental conditions (e.g., cell line, culture time, equilibration time, electrical stimulation settings, and raw data values).NEW & NOTEWORTHY We demonstrate that iCell cardiomyocytes2 electrophysiology measurements are impacted by deviations in experimental techniques including electrical stimulation protocols, equilibration time, well-to-well variability, and length of hiPSC-CM culture. Furthermore, our results indicate that hiPSC-CM drug responsiveness changes within the first 2 wk following defrost.

Effects of temporal changes in resting heart rate on future diabetes-related outcomes.

Most studies have analyzed the relationship between resting heart rate (RHR) measured at only one time point and future clinical events. The current study aims to investigate the impact of long-term RHR changes on future clinical outcomes in a decade-long cohort with type 2 diabetes mellitus (T2DM). The two-staged follow-up involved 2,513 T2DM participants. The first stage (2008-2014) intended to identify levels and trends in RHR changes, while the second stage (2014-2018) attempted to collect new occurrence records of clinical results. Cox proportional hazards models were applied to predict hazard ratios (HRs), along with 95% confidence interval (CI) for the correlation between RHR changes and future events. There is no significant correlation between baseline RHR levels and long-term clinical events. According to the range of RHR change, compared with the stable RHR group, the adjusted HRs for cardiovascular events and all-cause death in the large increase group were 3.40 (95% CI: 1.33-8.71, p=0.010) and 3.22 (95% CI: 1.07-9.64, p=0.037), respectively. While the adjusted HRs for all-cause death and major adverse cardiac and cerebrovascular events (MACCE) in the moderate decrease group were 0.55 (95% CI: 0.31-0.96, p=0.037) and 0.51 (95% CI: 0.26-0.98, p=0.046). According to the trend of RHR, compared with the normal-normal group, the adjusted HRs for composite endpoint events and cerebrovascular events in the normal-high group were 1.64 (95% CI: 1.00-2.68, p=0.047) and 2.82 (95% CI: 1.03-7.76, p=0.043), respectively. Changes in RHR had predictive value for long-term clinical events in diabetic populations. Individuals with significantly elevated RHR over a particular period of time showed an increased risk of adverse events.

Effect of temporal changes in stamen position on reproductive success in flowers with many stamens: Manipulations of stamen position.

Male and female reproductive success is enhanced (increased outcrossing and seed production, respectively) by stamen movement in species that have few stamens per flower. Does such enhancement also occur in species that have many stamens per flower? We examined the effects of stamen movement on male and female reproductive success in Anemone flaccida, which has many stamens per flower. We measured stamen movement, including temporal changes in anther-stigma and anther-anther distances. We experimentally fixed stamens in their pre- or post-movement positions. The anthers moved horizontally away from the stigmas with increasing flower age, thus reducing female-male interference. The dehisced anthers tended to move farther from the stigmas, while the undehisced or dehiscing anthers remained closer to them. The number of anthers touched per flower visit was higher in flowers whose stamens were fixed in the pre-movement position than in flowers whose stamens were fixed in the post-movement position or in flowers that were not manipulated. Thus, this position may promote male reproductive success. Seed production was lower for the untreated flowers than for those with stamens fixed in the post-movement position, suggesting that the post-movement stamen position is advantageous and stamen movement is suboptimal for female reproductive success. Stamen movement promotes male reproductive success in the early flowering stage and female reproductive success in the late flowering stage. In species having many stamens per flower, female-male interference can be reduced, but not eliminated, by stamen movement due to the conflict between female and male reproductive successes.

Spatio-temporal variation of bacterial community structure in two intertidal sediment types of Jiaozhou Bay

The intertidal sediment environment is dynamic and the biofilm bacterial community within it must constantly adapt, but an understanding of the differences in the biofilm bacterial community within sediments of different types is still relatively limited. The semi-enclosed Jiaozhou Bay has a temperate monsoon climate, with strong currents at the mouth of the bay. In this study, the structure of the bacterial community in Jiaozhou Bay sediment biofilms are described using high-throughput 16 S rRNA gene sequencing and the effects of temporal change and different sediment environment types are discussed. Alpha diversity was significantly higher in sandy samples than in muddy samples. Sandy sediments with increased heterogeneity promote bacterial aggregation. Beta diversity analysis showed significant differences between sediment types and between stations. Proteobacteria and Acidobacteria were significantly more abundant at ZQ, while Campilobacterota was significantly more abundant at LC. The relative abundances of Bacteroidetes, Campilobacterota, Firmicutes, and Chloroflexi were significantly higher in the muddy samples, while Actinobacteria and Proteobacteria were higher in the sandy samples. There were different phylum-level biomarkers between sediment types at different stations. There were also different patterns of functional enrichment in biogeochemical cycles between sediment types and stations with the former having more gene families that differed significantly, highlighting their greater role in determining bacterial function. Bacterial amplicon sequence variant variation between months was less than KEGG ortholog variation between months, presumably the temporal change had an impact on shaping the intertidal sediment bacterial community, although this was less clear at the gene family level. Random forest prediction yielded a combination of 43 family-level features that responded well to temporal change, reflecting the influence of temporal change on sediment biofilm bacteria.

Evaluation of Soundscape Perception in Urban Forests Using Acoustic Indices: A Case Study in Beijing

Soundscape is an essential component of urban forest landscapes, acoustic indices can be effectively used to monitor biodiversity, but whether they can be used for soundscape perception assessments needs to be further explored. In this study, soundscape recordings were collected in Beijing Eastern Suburban Forest Park, and acoustic indices were used to explore the relationship between the acoustic environment and soundscape perception, as well as the possible effects of temporal changes. To achieve this, audio recordings collected in spring and summer were divided, and a total of 90 audio segments were extracted from three time periods—morning, afternoon, and evening—to calculate the acoustic index and complete a questionnaire survey. The urban forest soundscape was evaluated according to the eight perceptual attribute quality indicators of ISO 12913, and generalized linear models were constructed to quantify the relationships between the acoustic indices and perception. The results showed that the temporal variation of the soundscape influenced the subjective evaluation, with the highest overall evaluation relating to the morning soundscape. The combination of acoustic indices explained the soundscape pleasantness (R2 = 0.58) better than the soundscape eventfulness (R2 = 0.54), demonstrating the utility of these indices in soundscape assessment. Linking acoustic indices to human perception generates innovative ideas and theoretical support for soundscape enhancement, contributing to a more pleasant acoustic environment and maximizing the social value of urban forests.

Risk of fracture according to temporal changes of low body weight changes in adults over 40 years: a nationwide population-based cohort study

BackgroundLow body weight is associated with an increased risk of fractures. However, the effect of temporal changes in the low body weight status on the risk of fracture remains unknown. This study aimed to evaluate the relationships between temporal changes in low body weight status and the risk of fractures in adults over the age of 40 years.MethodsThis study included data on adults over 40 years old who underwent two biannual consecutive general health examinations between January 1, 2007 and December 31, 2009 extracted from the National Health Insurance Database, a large nationwide population database. Fracture cases in this cohort were monitored from the time of the last health examination to the end of the designated follow-up period (from January 1, 2010 to December 31, 2018) or the participant's death. Fractures were defined as any fracture resulting in hospitalization or outpatient treatment claim after the date of general health screening. The study population was then separated into four groups based on the temporal changes in low body weight status as follows: low body weight to low body weight (L-to-L), low body weight to non-low body weight (L-to-N), non-low body weight to low body weight (N-to-L), and non-low body weight to non-low body weight (N-to-N). The hazard ratios (HRs) for new fractures, depending on weight changes over time, were calculated using Cox proportional hazard analysis.ResultsAdults in the L-to-L, N-to-L, and L-to-N groups had a substantially increased risk of fractures after multivariate adjustment (HR, 1.165; 95% confidence interval [CI], 1.113–1.218; HR, 1.193; 95% CI, 1.131–1.259; and HR, 1.114; 95% CI, 1.050–1.183, respectively). Although the adjusted HR was greater in participants who changed into having a low body weight, followed by those with consistently low body weight, those with low body weight remained to have an elevated risk of fracture independent of weight fluctuation. Elderly men (aged over 65 years), high blood pressure, and chronic kidney disease were significantly associated with an increase in fractures (p < 0.05).ConclusionIndividuals aged over 40 years with low body weight, even after regaining normal weight, had an increased risk of fracture. Moreover, having a low body weight after having a normal body weight increased the risk of fractures the most, followed by those with consistently low body weight.

How do circadian rhythms and neural synchrony shape networked cooperation?

This study investigates the effects of temporal changes at the individual and social levels and their impact on cooperation in social networks. A theoretical framework is proposed to explain the probability of cooperation as a function of endogenously driven periodic temporal variation and neural synchrony modeled as a diffusion process. Agents are simulated playing a prisoner’s dilemma game, with and without evolution, in a two-player setting and on networks. Most importantly, we find that temporal variation and synchrony influence cooperation patterns in a non-trivial way and can enhance or suppress cooperation, depending on exact parameter values. Furthermore, some of our results point to promising future research on human subjects. Specifically, we find that cooperators can dramatically increase their payoff—as opposed to defectors—if neural synchrony is present. Furthermore, the more heterogeneous the synchrony between two agents, the less they cooperate. In a network setting, neural synchrony inhibits cooperation, and variation in circadian patterns counteracts this effect.Call: Hidden Order Behind Cooperation in Social Systems.

Unveiling the ghosts of landscapes past: Changes in landscape connectivity over the last decades are still shaping current woodland plant assemblages

Abstract In ever‐changing landscapes, there is increasing evidence that current plant assemblages are shaped by the temporal dynamics of landscape connectivity. So far, attempts to take the temporal dynamics of connectivity into account have only focused on the degree of connectivity at one or several moments in time, but neglected the cumulative effects of temporal changes in connectivity. We investigated the effects of the temporal dynamics of landscape connectivity (i.e. the degree of connectivity, the magnitude and the variability of its temporal changes) over the last seven decades on current woodland plant herbaceous assemblages. The assemblages were described using a taxonomic approach combined with a functional approach based on four traits linked to the colonisation capacity of plant species. The taxonomic diversity of current woodland assemblages did not respond to the degree of connectivity nor to the magnitude and the variability of temporal changes, but the mean and/or the diversity of trait values linked to their colonisation capacity did. Responses, mainly driven by generalist species, were modulated by the type of connectivity trend experienced by woodlands. In woodlands experiencing an upward connectivity trend, high magnitude of temporal changes in connectivity increased the abundance of species that invest mostly in sexual reproduction at the expense of vegetative reproduction whereas the degree of connectivity and the variability of its temporal changes had no effect. In woodlands experiencing a downward connectivity trend, the diversity of seed mass values was independent on the magnitude but decreased with the variability of temporal changes, and increased with the degree of connectivity. Synthesis. Overall, we show that, besides the degree of connectivity, the cumulative effects of decades of changes in connectivity shape woodland plant community assembly by selecting for particular trait values in plant species. This study opens new perspectives for integrating the temporal dynamics of landscape connectivity in the theoretical framework of plant assembly rules. It should also be considered in the development of management strategies to restore and maintain landscape connectivity.

Assessing protected area network effectiveness through the temporal change in avian communities’ composition

Current rates of land use are driving temporal changes in avian communities. Thus, it is essential to properly designate and manage protected areas since they mitigate the adverse effects of temporal changes on species populations. By using common bird monitoring data in Czechia from two periods (2005/2006 and 2014/2015), we calculated two indices of temporal change per each site, the Jaccard dissimilarity index (temporal dissimilarity between the community composition) and the difference in bird species richness between both periods (delta bird species richness). We tested three main predictions on temporal change in bird communities between protected and unprotected areas: (i) bird species richness will be higher inside protected areas, (ii) temporal changes in avian communities will be lower inside protected areas, (iii) the effect of protected areas will interact with land-use types, land-use richness, and altitudinal zones. Bird species richness was higher inside protected areas in 2014/2015, ten years after the implementation of Natura 2000 in Czechia. Both indices of temporal change were lower inside protected areas. The interactions of protected areas and land-use types on the indices of temporal change were not significant. However, interactions with altitudinal zones had a significant positive effect on the indices, i.e., in higher altitudes, delta bird species richness and higher dissimilarity levels. Our study underlines the importance of protected areas for conservation by buffering the consequences of factors driving temporal community changes. Together, our results indicate a positive ‘umbrella’ effect of protected areas on avian communities that was likely facilitated by the implementation of Natura 2000.

Cardiovascular outcomes associated with treatment of type 2 diabetes in patients with ischaemic heart failure.

AimThe optimal strategy for diabetes control in patients with heart failure (HF) following myocardial infarction (MI) remains unknown. Metformin, a guideline‐recommended therapy for patients with chronic HF and type 2 diabetes mellitus (T2DM), is associated with reduced mortality and HF hospitalizations. However, worse outcomes have been reported when used at the time of MI. We compared outcomes of patients with T2DM and HF of ischaemic aetiology according to antidiabetic treatment.Methods and resultsThis study used linked data from primary care, hospital admissions, and death registries for 4.7 million inhabitants in England, as part of the CALIBER resource. The primary endpoint was a composite of cardiovascular mortality and HF hospitalization. The secondary endpoints were the individual components of the primary endpoint and all‐cause mortality. To evaluate the effect of temporal changes in diabetes treatment, antidiabetic medication was included as time‐dependent covariates in survival analyses. The study included 1172 patients with T2DM and prior MI and incident HF between 3 January 1998 and 26 February 2010. Five hundred and ninety‐six patients had the primary outcome over median follow‐up of 2.53 (IQR: 0.98–4.92) years. Adjusted analyses showed a reduced hazard of the composite endpoint for exposure to all antidiabetic medication with hazard ratios (HRs) of 0.50 [95% confidence interval (CI): 0.42–0.59], 0.66 (95% CI: 0.55–0.80), and 0.53 (95% CI: 0.43–0.65), respectively. A similar effect was seen for all‐cause mortality [HRs of 0.43 (95% CI: 0.35–0.52), 0.57 (95% CI: 0.46–0.70), and 0.34 (95% CI: 0.27–0.43), respectively].ConclusionsWhen considering changes in antidiabetic treatment over time, all drug classes were associated with reduced risk of cardiovascular mortality and HF hospitalization.

Precipitation effects on nematode diversity and carbon footprint across grasslands.

Free-living nematodes are one of the most diverse metazoan taxa in terrestrial ecosystems and are critical to the global soil carbon (C) cycling through their role in organic matter decomposition. They are highly dependent on water availability for movement, feeding, and reproduction. Projected changes in precipitation across temporal and spatial scales will affect free-living nematodes and their contribution to C cycling with unforeseen consequences. We experimentally reduced and increased growing season precipitation for 2years in 120 field plots at arid, semiarid, and mesic grasslands and assessed precipitation controls on nematode genus diversity, community structure, and C footprint. Increasing annual precipitation reduced nematode diversity and evenness over time at all sites, but the mechanism behind these temporal responses differed for dry and moist grasslands. In arid and semiarid sites, there was a loss of drought-adapted rare taxa with increasing precipitation, whereas in mesic conditions increases in the population of predaceous taxa with increasing precipitation may have caused the observed reductions in dominant colonizer taxa and yielded the negative precipitation-diversity relationship. The effects of temporal changes in precipitation on all aspects of the nematode C footprint (respiration, production, and biomass C) were all dependent on the site (significant spatial×temporal precipitation interaction) and consistent with diversity responses at mesic, but not at arid and semiarid, grasslands. These results suggest that free-living nematode biodiversity and their C footprint will respond to climate change-driven shifts in water availability and that more frequent extreme wet years may accelerate decomposition and C turnover in semiarid and arid grasslands.

Analysing of atmospheric conditions and their effects on air quality in Istanbul using SODAR and CEILOMETER.

In this study, first, air pollution that is caused by the air pollutants' concentration exceeding the limit value in Istanbul between 2017 and 2020 were analysed. In addition to this analysis, the effects of meteorological parameters on pollution were also examined within the same period of time. Second, for a 14-day period during which the concentration values of the air pollutants were calculated higher than the standards, therefore, were selected as an episode. In that respect, measurements of both pollutant and meteorological parameters were obtained from air quality monitoring stations. The Weather Research and Forecasting (WRF) model was used to examine the changes of meteorological parameters in the surface and upper atmospheric levels. The cross-correlation function (CCF) was performed together with both air quality monitoring station and the WRF model output data to examine the effects of temporal changes in meteorological parameters on air pollutant concentrations on a temporal scale. In addition, some meteorological parameters were obtained from remote sensing systems (SODAR and Ceilometer). Finally, with the help of the trajectory analysis model, it was determined whether the pollutant parameters were transported or not. Consequently, within a 3-year period, the most critical parameters in terms of pollution throughout the city were assessed as NO2 and PM10. Moreover, low wind speeds and high pressure values during the episode prevented the dispersion of pollutants and caused air pollution in Istanbul.

Time course effect of corticospinal excitability for motor imagery.

This study examined the effect of temporal changes in corticospinal excitability in motor imagery (MI) and the effect of real-time guides for MI on excitability changes. The MI task involved wrist flexion and motor evoked potentials using transcranial magnetic stimulation were recorded and examined from the flexor carpi radialis. Ballistic (momentary MI) and tonic (continuous MI) conditions were used, and the duration of each MI was different. In Experiment 1, each MI task was performed using an acoustic trigger. In Experiment 2, a real-time guide was presented on a computer screen, which provided a visual indication of the onset and duration of the MI task through via moving dots on the screen. The results indicate that the corticospinal excitability changed differently, depending on the duration of MI. Additionally, with real-time guides, the change in corticospinal excitability became clearer. Thus, corticospinal excitability changes due to the temporal specificities of MI, as well as with actual motor output. Moreover, if MI is actively performed without a guide, it is likely to show an unintended change in corticospinal excitability. It is suggested that when MI is performed with visual guide, the excitatory changes of the corticospinal tract might be different from the actual motor output. Therefore, when using MI for mental practices, it is possible to improve the effect of a guide for MI, such as a visual indicator for motor output. Additionally, when examining neural activities in MI, it may be necessary to consider the characteristics of motion performed by MI.

Benchmarking Framework for Multitemporal SAR Despeckling

In this article, we propose a novel benchmarking framework for a quantitative assessment of the performance of despeckling algorithms for multitemporal synthetic aperture radar (SAR) imagery. A number of canonical scenes and data sets are analyzed so as to investigate both speckle reduction and feature preservation capabilities of the filters. Despeckling performance is evaluated by proper quality measures that are defined according to the scene. Due to the lack of real-world speckle-free SAR images, the proposed benchmarking tool relies on an accurate and well-assessed SAR simulator which allows for generating realistic SAR images accounting for electromagnetic (EM) and geometrical parameters of the sensed surface. Accuracy and convergence properties of filters are first measured on scenes with stationary reflectivity. Then, for a more realistic performance prediction in practical situations, the effects of temporal changes of the scene reflectivity on the despeckled images are measured on time series with time-varying reflectivity. In the latter case, performance parameters are intended to measure the capability of the filter to preserve both the perturbation and its impact on the other bands. The whole benchmarking framework is applied to a representative set of state-of-the-art multitemporal filters. Interestingly, their performance as evaluated by means of our framework is well in agreement with (qualitative) visual inspections by SAR specialists. Proposed quality metrics are measured under the hypothesis of uncorrelated bands, which defines the best case for most multitemporal filters. A numerical sensitivity analysis of the performance of filters against correlation coefficient is carried out to investigate the temporal correlation effects on the despeckled time series.

Temporal Variations of the Marine Geoid

AbstractThe effects of temporal changes in the marine geoid on estimates of the ocean dynamic topography are being investigated. Influences from mass redistribution due to changes of land hydrology, ice sheets, glacial isostatic adjustment (GIA), and ocean and atmospheric dynamics are considered, and the associated crustal deformation is included. The strongest signals are associated with the seasonal cycle caused by changes in terrestrial water storage and ice sheets as well as the redistribution of atmospheric mass. Second to this is the importance of an overall trend caused by GIA and decreasing ice sheets over Greenland and Antarctica. On long spatial scales, the amplitude of regional trends estimated for the geoid height has a sizable fraction of those from sea level anomaly (SLA) for the period 1993–2016, also after subtraction of steric height of the upper 1,000 m to analyze trends in deep ocean geostrophic currents. The estimated strong negative geoid height trend south of Greenland for the period 1993–2016 opposes changes in dynamic sea level for the same period thereby affecting past studies on changes of both the strength of the subpolar gyre based on SLA and the meridional overturning circulation on a section between Cape Farewell and Portugal applying ocean dynamic topography and hydrography. We conclude that temporal geoid height trends should be considered in studies of (multi)decadal trends in sea level and circulation on large spatial scales based on altimetry data referenced to a geoid field.

The burden of childhood pneumonia in India and prospects for control

Pneumonia continues to be the leading cause of mortality in children worldwide, with India accounting for 20% of those deaths and a higher burden of childhood pneumonia than any other country.1 In The Lancet Child & Adolescent Health, Brian Wahl and colleagues2 report the first comprehensive evaluation of state-specific pneumonia incidence in children in India using a risk factor-based modelling approach. By calculating the effect of temporal changes in prevalence of well-known pneumonia risk factors such as malnutrition, incomplete immunisation, and exposure to indoor air pollution on incidence, the authors estimated the change in pneumonia morbidity over time.