Predicting neonatal sepsis using features of heart rate variability, respiratory characteristics and ECG-derived estimates of infant motion

\u3cp\u3eThis study in preterm infants was designed to characterize the prognostic potential of several features of heart rate variability (HRV), respiration, and (infant) motion for the predictive monitoring of late-onset sepsis (LOS). In a neonatal intensive care setting, the cardiorespiratory waveforms of infants with blood-culture positive LOS were analyzed to characterize the prognostic potential of 22 features for discriminating control from sepsis-state, using the Naïve Bayes algorithm. Historical data of the subjects acquired from a period sufficiently before the clinical suspicion of LOS was used as control state, whereas data from the 24 h preceding the clinical suspicion of LOS were used as sepsis state (test data). The overall prognostic potential of all features was quantified at three-hourly intervals for the period corresponding to test data by calculating the area under the receiver operating characteristics curve. For the 49 infants studied, features of HRV, respiration, and movement showed characteristic changes in the hours leading up to the clinical suspicion of sepsis, namely, an increased propensity toward pathological heart rate decelerations, increased respiratory instability, and a decrease in spontaneous infant activity, i.e., lethargy. While features characterizing HRV and respiration can be used to probe the state of the autonomic nervous system, those characterizing movement probe the state of the motor system-dysregulation of both reflects an increased likelihood of sepsis. By using readily interpretable features derived from cardiorespiratory monitoring, opportunities for pre-emptively identifying and treating LOS can be developed.\u3c/p\u3

The butoxylation of dodecylamine: reaction mechanism and kinetics

The reaction mechanism and kinetics of the butoxylation of dodecylamine were investigated experimentally using a semi-batch, fully liquid process at temperatures ranging from 120 °C to 150 °C and varying stoichiometric ratios of the reactants. In addition, the catalytic effect of adding 1-3%mol of twelve different functional organic species containing hydroxyl, aldehyde, amine, and/or amide functional groups was studied. It was found that only proton donating groups increase the observed reaction rate. In particular hydroxyl groups in combination with an amine group resulted in a strong acceleration of the reaction. Since the reaction intermediates mono-and dibutoxylated amines have this combination, an auto-catalytic reaction mechanism and corresponding rate law are proposed. The kinetic constants were fitted to the experimental data as a function of temperature, following an Arrhenius type of dependency. The results from the model describe the experimental data with 95% accuracy. Moreover, the results show that the butoxylation of dodecylamine, as a model reactant for a short substituted ethylene oxide, with fatty amines, follows the same mechanism and has similar kinetics as epoxide hardening reactions with amines

Designing image-based control systems considering workload variations

We consider the problem of designing an Image-\u3cbr/\u3eBased Control (IBC) application mapped to a multiprocessor platform. Sensing in IBC consists of compute-intensive image processing algorithms whose execution times are dependent on image workload. The challenge is that the IBC systems have a high (worst-case) workload with significant workload variations. Designing controllers for such IBC systems typically consider the worst-case workload that results in a long sensing delay with suboptimal quality-of-control (QoC). The challenge is: how to improve the QoC of IBC for a given multiprocessor platform allocation?\u3cbr/\u3e\u3cbr/\u3eWe present a controller synthesis method based on a Markovian jump linear system (MJLS) formulation considering workload variations. Our method assumes that system knowledge is available for modelling the workload variations as a Markov chain. We compare the MJLS-based method with two relevant control paradigms - LQR control considering worst-case workload, and switched linear control - with respect to QoC and available system knowledge. Our results show that taking into account workload variations in controller design benefits QoC. We then provide design guidelines on the control paradigm to choose for an IBC application given the requirements and the system knowledge

How does walkability change behavior?:a comparison between different age groups in the Netherlands

Empirical research provides evidence that, in neighborhoods with higher walkability, individuals make more walking trips. However, it is not clear what the exact nature is of the relationships between neighborhood walkability and walking trips, since a higher walking frequency can be explained in different ways. This study examined whether the extra walking trips in better walkable neighborhoods are related primarily to trip generation, destination choice, or transport mode choice and whether this is the same for different age groups. A neighborhood fixed effects regression analysis was conducted in a first step to obtain a walkability measure for each neighborhood in the Netherlands including systematic as well as unobserved effects. Subsequently, the estimated fixed effects were used as walkability data for a path analysis based on a causal model to test the hypotheses stated. The results of the path analysis show direct relationships of neighborhood walkability with trip generation, destination choice, and transport mode choice, after controlling for the mutual relationships between the activity and trip variables. Comparing different age groups (i.e., children, adults, and elderly), the differences found mostly concerned the relationship between neighborhood walkability and trip generation. We concluded therefore that conditions for walkability are not the same for all age groups

Impact of turbulence models and roughness height in 3D steady RANS simulations of wind flow in an urban environment

\u3cp\u3eThe accuracy and reliability of 3D steady RANS CFD simulations of wind flow in urban environments can be affected by numerical settings including the turbulence model and the imposed roughness heights. In that regard, various k-ε and k-ω turbulence models and roughness height (k\u3csub\u3es\u3c/sub\u3e) values are commonly used when predicting wind flow in urban environments. However, it is insufficiently known to which extent the CFD results may be influenced by these settings when simulating wind flows in complex urban environments with large changes in surface roughness. This is the scope of the present paper, for which wind-tunnel (WT) measurements and CFD simulations were performed on a reduced-scale model (1:300) of a district of Livorno (Italy). Mean wind speed (U), turbulent kinetic energy (k) and turbulence dissipation rate (ε) profiles from WT measurements and CFD simulations were compared at 25 positions and deviations between experimental and numerical results were quantified by three metrics: fractional bias, correlation coefficient and fraction of data within a factor of 1.3. The turbulence model selection had a larger impact compared to the surface roughness selection on U, k and ε values. The best and worst performing turbulence models (e.g. for α = 240° at 0.02 m above the bottom) showed a deviation in terms of correlation (0.89 and 0.61, respectively) of about 0.28. Conversely, the best and worst performing roughness set, (e.g. for α = 240° at 0.02 m above the bottom), showed a deviation in terms of correlation (0.77 and 0.78, respectively) of only 0.01.\u3c/p\u3

Optimization of combustion in micro combined heat and power (mCHP) system with the biomass-Stirling engine using SiO2 and Al2O3 nanofluids

In this paper, a typical mCHP system was integrated by gamma type Stirling engine to meet electric, heating and hot water demands. The combustion test results, which is a key technology for small and micro scale mCHP systems have been presented and the combustion parameters for the Gamma type Stirling engine power system are discussed. Finally, the effect of SiO2 and Al2O3 nanoparticles, dispersed in Polyalkylene glycol (PAG) of mCHP system on the viscosity and thermal conductivity, were investigated. Also, the effect of sawdust biomass fuel on mCHP system emissions (such as CO, NOx, HC) have investigated. The test results confirm the fact that Stirling engines that are driven by the temperature of biomass gases are able to achieve a valuable output power. Also, Analysis of pollutants showed that by increasing of sawdust mass flow rate from 0 to 0.14 (g/s), CO emissions increased 164 Vol%, also HC and NOx emissions increased 295-24 ppm respectively. Finally, the comparison between Al2O3/PAG and SiO2/PAG nano-lubricant demonstrate that Al2O3/PAG have better performance, therefore, the findings suggest Al2O3/PAG with a volume concentration of 0.010% as an optimum and best performance nano-lubricant for mCHP system. On the basis of the experimental results, we conclude that using the SiO2 and Al2O3 nanofluids in mCHP system can be introduced as new way to improve the performance of mCHP

A soft transporter robot fueled by light

Mobile organisms with ability for locomotion and transportation, such as humans and other animals, utilize orchestrated actuation to perform actions. Mimicking these functionalities in synthetic, light‐responsive untethered soft‐bodied devices remains a challenge. Inspired by multitasking and mobile biological systems, an untethered soft transporter robot with controlled multidirectional locomotion with the ability of picking up, transporting, and delivering cargo driven entirely by blue light is created. The soft robot design is an ensemble of light‐responsive liquid crystalline polymers that can harness motion either collectively or individually to obtain a high degree of motion control for the execution of advanced tasks in a dry environment. Through orchestrated motion of the device's “legs”, single displacement strides, which exceed 4 mm and can be taken in any direction, allow for locomotion around objects. Untethered cargo transportation is demonstrated by a pickup and release mechanism using the device's “arms”. This strategy demonstrates the constructive harnessing of orchestrated motion in assemblies of established actuators, performing complex functions, mimicking constructive behavior seen in nature

Verduurzaming van de huurwoningen: rol van motivatie en communicatie

De duurzaamheidsopgave in de sociale sector is omvangrijk en betreft ruim twee miljoen huurwoningen en tientallen miljarden euro’s aan investeringen door woningcorporaties. Een extra uitdaging is de wettelijke eis dat huurders moeten instemmen met de duurzaamheidsmaatregelen zoals woningisolatie, zonnepanelen, et cetera en de eventuele huurverhoging die hiermee gaat gepaard. In dit artikel wordt onderzocht hoeveel huurverhoging sociale huurders bereid zijn te dragen bij verschillende duurzaamheidsmaatregelen en hoe informatie en communicatie hun beslissingen hierover beïnvloedt.\u3cbr/\u3e\u3cbr/\u3eWe focussen op de maatregelen die voorkomen in de scenario’s Routekaart CO2-neutraal van de Nederlandse branchevereniging van woningcorporaties Aedes (2017, 2018). De maatregelen omvatten onder meer: woningisolatie in verschillende varianten, zonnepanelen, installatie van HR++ apparaten, overstappen van aardgasverwarming naar een warmtepomp, etc