Instantaneous Effect Research Articles

Instantaneous effect of real-time avatar visual feedback on interlimb coordination during walking post-stroke

BackgroundGait asymmetry, which is common after stroke, is typically characterized using spatiotemporal parameters of gait that do not consider the aspect of movement coordination. In this manuscript, we examined whether an avatar-based feedback provided as a single-session intervention to improve gait symmetry also improved inter-limb coordination among people with stroke and we examined the relationship between changes in coordination and step length symmetry. MethodsTwelve stroke participants walked on a self-paced treadmill with and without a self-avatar that replicated their locomotor movements in real time. Continuous relative phase and angular coefficient of correspondence calculated using bilateral sagittal hip movements were used to quantify temporal and spatial interlimb coordination, respectively. Spatial gait symmetry, previously shown to improve with the avatar feedback, was quantified using step length ratio between both limbs, with the largest value as numerator. FindingsParticipants who improved their spatial symmetry during avatar exposure also improved their temporal coordination, while spatial coordination remained unchanged. Overall, improvements in spatial symmetry correlated positively with improvements in temporal coordination. The non-paretic hip and paretic ankle angle excursion in the sagittal plane also significantly increased during avatar exposure. InterpretationImprovements in gait symmetry may be explained by changes in interlimb coordination. Current data and existing literature further suggest that such improvements are largely driven by adaptations in non-paretic leg movements, notably at the hip. By providing real-time information on walking movements not affordable in other ways, avatar-based feedback shows great potential to improve gait symmetry and interlimb coordination post-stroke.

Pest control switching models with instantaneous and non-instantaneous impulsive effects

In this paper, it is considered that the predation rate and transformation rate of natural enemies on pests in different time periods of pesticide action and non-action are different, and after spraying pesticides, the pesticides kill the pests and natural enemies instantaneously, and at the same time bring non-instantaneous residual effects on them. Firstly, an integrated pest control switching model with instantaneous and non-instantaneous impulsive effects at the fixed time is proposed. It assumes that spraying pesticides is more frequently used than releasing natural enemies. The sufficient condition for the global asymptotic stability of the pest-eradication periodic solution is obtained. By numerical simulations, we find that the system we study has many complex dynamics including period-doubling bifurcation, period-halving bifurcation, chaos and multiple attractors. Further, the effects of some key parameters on the threshold for pest eradication are analyzed. The results imply that it is not that the more frequent, the more conductive to pest control, and within each releasing period, applying pesticides too early or too late is not good for pest control. Finally, with the purpose of preventing pests below the economic injury level, a state-dependence pest control switching model with instantaneous and non-instantaneous impulsive effects is investigated numerically. Our results show that the frequency of applying pesticides depends on the key parameters of the established system, such as initial population density, the releasing amount of natural enemies and the period of releasing natural enemies, etc.

Whitening Optical Effect of New Chewing Gums

Background: Today, many treatments are available to enhance the color of teeth, but they require a few days to weeks to deliver this effect. Objective: To evaluate the instantaneous optical whitening effect of two new sugar-free chewing gums and one dentifrice of proven efficacy versus one placebo chewing gum. Methods: This was a single-blind, parallel trial. 424 participants entered the study and were randomly allocated to four groups. They received a personal silicone mask with a calibrated hole at one upper incisor to apply a dental colorimeter. The tools tested were chewing-gum containing indigotine (E132-FD&C Blue 2) and spirulina, chewing-gum containing only spirulina, chewing-gum placebo, and dentifrice containing Blue Covarine. Vita® Easyshade scored the tooth color, and the WIO and WID whiteness indexes were calculated. For chewing gums, the color of the teeth was scored before the assumption and after 2’30” of mastication. For dentifrice, participants brushed for 1’30”, then rinsed, and the color was scored before brushing and after 2’30”. Statistical analysis was performed by ANOVA and Tukey post-hoc. Results: The two experimental whitening chewing gums and the dentifrice significantly increased the WIO and the WID indexes from the baselines (p<0.001). Moreover, their effects were statistically greater than those reported for the placebo chewing gum (p<0.05) but not significatively different among them (p=NS). Conclusion: All the tested whitening tools showed an instant optical whitening perception. Further studies are required to assess the intensity of the effect over a prolonged time to meet the people's request for fast whitening tools. The clinical trial registration no. is PVM-2020-01.

Measuring trade rule uncertainty and its impacts on the commodity market

A measurement of global trade rule uncertainty (TRU) is developed by performing textual data mining on global media reports and trade remedy cases. Spikes in TRU are connected with major events that result in uncertainty in trade rules. The empirical results reveal that TRU has instantaneous effect to energy and agricultural prices, a delayed effect on nonferrous and metal prices, a continuous effect on sugar prices in Chinese commodity markets, and no significant impacts on US commodities. Our work not only contributes to extending measurements of uncertainty but also can help quantify the impacts of uncertainty on the real economy.

Application of High Spatiotemporal Air Pollution Surfaces and Participants’ Activity Space for Identification of the Instantaneous Effect of Air Pollution on Rescue Medication Use for California Residents

Application of High Spatiotemporal Air Pollution Surfaces and Participants’ Activity Space for Identification of the Instantaneous Effect of Air Pollution on Rescue Medication Use for California Residents

The impact of comprehensive public hospital reforms on the direct medical cost of inpatients with coronary heart disease.

ObjectivesTo curb the unreasonable growth of medical expenses and reduce the burden of medical treatment, Beijing launched two rounds of comprehensive reform of public hospitals. In the two reforms, the addition of drugs and consumables was canceled successively. This study compared the changes in the direct medical cost of inpatients with coronary heart disease (CHD) in the three stages of two comprehensive public hospital reforms in Beijing and provides data support for health reform policies.SettingCHD diagnosis and treatment data were extracted from the Hospital Information System (HIS) of 33 public hospitals. The total amount and composition of the direct medical expenses of CHD inpatients in the three stages were calculated. Interrupted time series analysis was used to study the instantaneous changes and trend changes in the three stages.ParticipantsThe data were obtained from the HIS system of 33 public hospitals above the second level in Beijing. A total of 66,647 medical and diagnosis records and 24,371,139 charge detail records were included.ResultsAfter the two reforms, the total cost for CHD inpatients with most clinical classifications and treatment methods decreased. The proportion of drug and consumable costs decreased significantly, whereas the proportion of medical consultation service costs increased. Drug-treated patients were mainly affected by the instantaneous reforms, percutaneous coronary intervention-treated patients were simultaneously affected by instantaneous and trending effects, and coronary artery bypass graft-treated patients were mainly affected by the reform trend.ConclusionThe overall change in the direct medical cost of CHD inpatients was consistent with the goal of the comprehensive medical reform of public hospitals in Beijing, which is “total control and structural adjustment.”

The Influence of Exchange Rate and Foreign Capital on the Performance of Inflation Targeting Framework in Indonesia

This study provides empirical evidence on the problem of the trilemma of monetary policy in an open economy, in the context of the effect of exchange rates and foreign capital flows on the performance of the ITF in Indonesia. The method used as an empirical estimate is the Structural Vector Autoregressive (SVAR) model. This model allows to include restrictions in the empirical estimation of parameters that measure the contemporaneous effect of one variable on another variable according to the structure of the macroeconomic model. Meanwhile, the lagged effects are estimated according to the VAR model. Therefore, the SVAR model is considered more appropriate than the ordinary VAR model because it can measure both the instantaneous effect and the intertemporal effect of the problem under study. The SVAR model uses restrictions that are consistent with the theoretical model in its estimation, regardless of the time-to-time effect of one variable on another. There are 9 variables in the SVAR model, namely: global risk, oil prices, federal funds rate, economic growth, inflation, interest rates, monetary policy, credit interest rates, foreign portfolio investment flows, and the rupiah exchange rate. All data used were obtained from several sources, including: Bank Indonesia, Central Statistics Agency, and IMF. Based on the estimation results, the exchange rate and foreign capital flows have a significant effect on inflation and economic growth, thus affecting the performance of the ITF in Indonesia. In particular, there is a relative influence between external factors, particularly global commodity prices, US monetary policy interest rates, and global risks, and domestic factors, particularly economic growth, monetary policy interest rates, and bank interest or credit rates. This study also concludes that in addition to inflation and economic growth considerations, Bank Indonesia also considers exchange rate movements in determining its interest rate policy response.

Enhanced CO2 hydrate formation via biopromoter coupled with initial stirring activation

CO2 sequestration based on hydrate technology is considered to be the most promising long-term CO2 sequestration technology. In this study, a method of using initial stirring to activate CO2 hydrate formation process was proposed in the aim of saving energy and avoiding the problem of stirring shaft stuck, where the stirring only played a role in activating hydrate formation process. Two amino acids, l-Methionine and d-leucine, were chosen as promoters for improving the formation kinetics of CO2 hydrates, and l-Methionine presents better than d-leucine. When the concentration of l-methionine solution is equal to or greater than 4 mmol/L, even with the initial stirring of 10 rpm within 8 min, T90 can be shortened to close to or less than 40 min with a high gas consumption of more than 7.3 mmol gas/mL water, where the promoting effect is similar to the condition of continuous stirring of about 100 min, indicating that about 90 % of the energy consumed for mechanical stirring can be saved. Moreover, an interesting phenomenon was observed that CO2 hydrates firstly nucleated inside the l-methionine solution, and a large number of small hydrate floccules rapidly formed and filled the entire solution under the action of magnetic stirring, which proved the instantaneous excitation effect of stirring on hydrate formation. This work contributes to rethinking the promoting roles of stirring and promoters in CO2 hydrate formation.

Instantaneous effects of mindfulness meditation on tennis return performance in elite junior athletes completing an implicitly sequenced serve return task.

Single-session meditation augmentation of sport-specific skill performance was tested with elite junior tennis athletes. Athletes completed one of two styles of mindfulness meditation (focused-attention or open-monitoring) or a control listening condition prior to performing an implicitly sequenced tennis serve return task involving the goal of hitting a target area placed on the service court. Unbeknownst to athletes, six distinct serves followed a repeating second-order conditional sequence for two task blocks before the sequence was altered in a third transfer block. Task performance was operationalized as serve return outcome and analyzed using beta regression modeling. Models analyzed group by block differences in the proportion of returned serves (i.e., non-aces), returns placed in the service court, and target hits. Contrary to previous laboratory findings, results did not support meditation-related augmentation of performance and/or sequence learning. In fact, compared to control, meditation may have impaired performance improvements and acquisition of serve sequence information. It is possible that the effects of single-session meditation seen in laboratory research may not extend to more complex motor tasks, at least in highly-trained adolescents completing a well-learned skill. Further research is required to elucidate the participant, task, and meditation-related characteristics that might promote single-session meditation performance enhancement.

An Extended Thermodynamics Model for Blood Flow

A model for blood flow is introduced in the context of the Rational Extended Thermodynamics (RET). The balance equations are applied to the two-hierarchy structure recently introduced by Ruggeri and Sugiyama. The constitutive relations are derived with universal physical principles and the remaining constitutive functions are evaluated by use of the kinetic theory. The model herein obtained is a hyperbolic generalization of a classical blood flow model. Our equations by construction have the same physical proprieties of the classical system; in addition, owing to its hyperbolic structure, our model avoids the unphysical feature of instantaneous diffusive effects which is typical of parabolic systems. Furthermore we expect that our model, as all RET systems, can describe the physical phenomena better than the classical ones when the fields change rapidly or one has steep gradients.

The announcement effects of a change in the Bank of Japan’s ETF purchase program: An event study

This study investigates the announcement effects of the Bank of Japan’s (BOJ) ETF purchase program on equity prices, focusing on the policy change made on March 19, 2021 when the BOJ announced that it would no longer purchase Nikkei225-tracking and JPX400-tracking ETFs but would purchase more TOPIX-tracking ETFs. A regression of intraday stock returns revealed that the announcement of a future decrease (increase) in the amount of BOJ purchases has the instantaneous effect of decreasing (increasing) stock prices.

Microwaves reduce water refractive index

Microwaves, long used as a convenient household appliance, have been increasingly used in industrial processes such as organic synthesis and oil processing. It has been proposed that microwaves can enhance these chemical processes via a non-thermal effect. Here we report the instantaneous effect of microwaves on the permittivity and phase velocity of light in water through the in-situ measurement of changes in refractive index. Microwave irradiation was found to reduce the water refractive index (RI) sharply. The reduction increased as a function of microwave power to a far greater extent than expected from the change in temperature. The phase velocity of light in water increases up to ~ 5% (RI of 1.27) during microwave irradiation. Upon stopping irradiation, the return to the equilibrium RI was delayed by up to 30 min. Our measurement shows that microwaves have a profound non-thermal and long-lasting effect on the properties of water. Further investigation is planned to verify if the observed RI reduction is restricted to the region near the surface or deep inside water bulk. The observation suggests a relationship between microwave-induced and the enhanced aqueous reactions.

Dormancy induced by oxidative damage during disinfection facilitates conjugation of ARGs through enhancing efflux and oxidative stress: A lagging response

Disinfection is known to greatly alter bacterial characteristics in water, and high horizontal gene transfer (HGT) frequency occurs in eutrophic conditions. Interestingly, these two seemingly irrelevant phenomena were closely linked by a lagging response of the increased conjugation frequency probably via daily water disinfection in this study. Three disinfection methods (UV, chlorine, and UV/chlorine) were selected to investigate the increased frequency of conjugation of ARGs during the stage of continuing culture after disinfection. The results showed that the conjugative transfer frequency was inhibited for all disinfection treatments after 24 h of co-incubation. Unexpectedly, after 3–7 days of co-cultivation, the HGT frequencies were increased by 2.71–5.61-fold and 5.46–13.96-fold in chlorine (30 min) and UV/chlorine (1 min) groups compared to the control, but not in UV-irradiated groups. A neglected lagging response was found for the first time, i.e., oxidative disinfection-induced dormancy promotes conjugative transfer of ARGs. Furthermore, mechanistic insights were gained from (1) membrane permeability, (2) conjugation-regulated system, (3) efflux pump system, and (4) oxidative stress system, suggesting the critical role of enhancing efflux and oxidative stress in the propagation of ARGs. Finally, the known instantaneous effect of oxidation disinfection was compared to address the controversial debate in this research field, proposing that the dormancy level of donor bacteria is the key to evaluating whether it can promote the HGT process. This study has important environmental implications for elucidating the transmission of ARGs after oxidation disinfection.

Stick or carrot for traffic demand management? Evidence from experimental economics

The debate between stick (penalties) and carrot (rewards) strategies has been widely carried out in various academic realms, including transportation. This paper seeks to compare the instantaneous and longitudinal effectiveness of a traditional penalty-based congestion pricing strategy and an innovative Incentive-Based Traffic Demand Management (IBTDM) strategy using an online interactive laboratory experiment focused on departure time choice. We also investigate the social-economic phenomena of loss aversion and risk aversion. The experimental results show that penalties and rewards can both positively induce sustainable travel behavior. The stronger demand-shifting performance of the penalty-based strategy at first demonstrates that ‘loss aversion’ does exist in TDM, at least initially. However, this loss aversion weakens as the experiment continues, which verifies the myopic loss aversion theory. Moreover, risky decision-making in the gambling games proves the existence of risk seeking, which violates the ‘certainty effect’. To overcome the disadvantage of laboratory experiment that participants need to accomplish the experiment all in once for considerably long time, an agent-based model is calibrated based on real participants’ behavior to further verify the long-term effectiveness of penalties and rewards, and to verify the effectiveness of other optimized penalty/reward schemes. The simulated results based on the agent-based model indicate that the theoretical optimal penalty scheme performs better in general in congestion alleviation, while a more reasonable reward scheme that considers psychological factors can achieve the same effectiveness in terms of total system travel time reduction. The findings of this research can be used to guide the design of TDM strategies, and the behavioral data collection approach based on our laboratory experiment is portable for future studies.

The impact of chief diversity officers on diverse faculty hiring

AbstractRacial diversity among faculty, students, and administrators is increasing at universities in the United States. These changes have been uneven, with growth in underrepresented students exceeding that of faculty diversity. To address these and other inequities, a growing number of universities have established an executive‐level chief diversity officer (CDO). Our study offers a first empirical examination of this effort at selected 4‐year U.S. universities from 2001 to 2019 using unique data on the initial hiring date of a CDO and publicly available demographic data. We provide a comprehensive overview of demographic trends within our data and find confidence intervals around the estimated instantaneous average treatment effect for an executive‐level CDO on diverse hiring tightly contain zero. Estimated treatment effects are small and lack statistical significance within 4 years of a CDO position being established. We discuss other possible factors that explain trends toward higher diversity on campus and several possible constraints.

Numerical Study on the Shear Stress Characteristics of Open-Channel Flow over Rough Beds

Bed shear stress is an important measure of benthic habitats since it is related to many ecological processes. In this study, we focused on the fluctuating characteristics of shear stress in rough-bed open-channel flows. The roughness element method was adopted to mimic natural rough beds and the Improved Delayed Detached Eddy Simulation (IDDES) model was used to obtain comprehensive information about shear stress near the rough bed. Three arrangement patterns of the roughness elements were simulated to compare their effects on flow structure and shear stresses. The arrangements of the roughness elements altered the Reynold stress and turbulent kinetic energy characteristics, due to the variance of blockage in lateral directions that led to flow detachment and changes in the flow directions. Quadrant analysis revealed the spatial variations of the instantaneous shear stress burst events at different locations in the wake. By using spectrum analysis, the accumulation of shear-stress energy from small to large vortex scales was estimated, which revealed that the instantaneous effect of the shear stress was significantly stronger than the effect of the time-averaged shear stress, especially on small scales. The results of this study suggest the significance of the fluctuation part of shear stress in further studies on ecological processes.

Fibrin Sealants: Challenges and Solutions.

Intraoperative bleeding and postoperative bleeding are major surgical complications. Tissue sealants, hemostats, and adhesives provide the armamentarium for establishing hemostatic balance, including the tissue sealant fibrin. Fibrin sealants combine advantages including instantaneous effect, biocompatibility, and biodegradability. However, several challenges remain. This review summarizes current fibrin product generations and highlights new trends and potential strategies for future improvement.

Partial Directed Coherence and the Vector Autoregressive Modelling Myth and a Caveat.

Here we dispel the lingering myth that Partial Directed Coherence is a Vector Autoregressive (VAR) Modelling dependent concept. In fact, our examples show that it is spectral factorization that lies at its heart, for which VAR modelling is a mere, albeit very efficient and convenient, device. This applies to Granger Causality estimation procedures in general and also includes instantaneous Granger effects. Care, however, must be exercised for connectivity between multivariate data generated through nonminimum phase mechanisms as it may possibly be incorrectly captured.

Identifying and modelling key physiological traits that confer tolerance or sensitivity to ozone in winter wheat

Tropospheric ozone threatens crop production in many parts of the world, especially in highly populated countries in economic transition. Crop models suggest substantial global yield losses for wheat, but typically such models fail to address differences in ozone responses between tolerant and sensitive genotypes. Therefore, the purpose of this study was to identify physiological traits contributing to yield losses or yield stability under ozone stress in 18 contrasting wheat cultivars that had been pre-selected from a larger wheat population with known ozone tolerance. Plants were exposed to season-long ozone fumigation in open-top chambers at an average ozone concentration of 70 ppb with three additional acute ozone episodes of around 150 ppb. Compared to control conditions, average yield loss was 18.7 percent, but large genotypic variation was observed ranging from 2.7 to 44.6 percent. Foliar chlorophyll content represented by normalized difference vegetation index and net CO2 assimilation rate of young leaves during grain filling were the physiological traits most strongly correlated with grain yield losses or stability. Accumulative effects of chronic ozone exposure on photosynthesis were more detrimental for grain yield than instantaneous effects of acute ozone shocks, or accelerated senescence of older leaves represented by changes in the ratio of brown leaf area/green leaf area index. We used experimental data of two selected tolerant or sensitive varieties, respectively, to parametrize the LINTULCC2 crop model expanded with an ozone response routine. By specifying parameters representing the distinct physiological responses of contrasting genotypes, we simulated yield losses of 7 percent (tolerant) or 33 percent (sensitive). By considering genotypic differences in ozone response models, this study helps to improve the accuracy of simulation studies, estimate the effects of adaptive breeding, and identify physiological traits for the breeding of ozone tolerant wheat varieties that could deliver stable yields despite ozone exposure.

Instantaneous effect of prolonged stretch on monosynaptic excitability in hemiplegic cerebral palsied children: Repeated measures design

Instantaneous effect of prolonged stretch on monosynaptic excitability in hemiplegic cerebral palsied children: Repeated measures design