Performance of The Decarboxylation Index To Predict CO2 Removal And Mechanical Ventilation Reduction Under VV-ECMO Or High-Flow ECCO2R

Background: Optimal decarboxylation dose under extracorporeal respiratory support to ensure sufficient reduction of mechanical ventilation stress remains unclear and understudied. The aim of this study was to assess the interdependence of blood flow (BF) and gas flow (GF) in predicting CO2 removal and mechanical ventilation reduction (MVR) under extracorporeal respiratory support. Methods: All patients who benefited from veno-venous ECMO (HLS-maquet 7.0, 1.8 m²) and high-flow ECCO2R (HLS-maquet 5.0, 1.3 m²) in our intensive care unit over a period of 18 months were included. CO2 removal was calculated from inlet/outlet blood gases performed in clinical practice during the first 7 days of oxygenator use. The relationship between the BF × GF product and CO2 removal or MVR was studied using linear regression models. Results: Eighteen patients were analysed, corresponding to 24 oxygenators and 261 datasets. CO2 removal was 393 mL/min (IQR, 310–526 mL/min) for 1.8 m2 oxygenators and 179 mL/min (IQR, 165–235 mL/min) for 1.3 m2 oxygenators. The decarboxylation index was associated linearly with CO2 removal (R2 = 0.62 and R2 = 0.77 for the two oxygenators, respectively) and MVR (R2 = 0.72 and R2 = 0.62, respectively). Values in the range 20−30L2/min2 were associated with an MVR ratio between 38% and 58% for 1.8 m2 oxygenators, and between 37% and 55% for 1.3 m2 oxygenators. Conclusion: The decarboxylation index is a simple parameter to predict CO2 removal and MVR under extracorporeal respiratory support. A BF of 2 L2/min2 or more may be necessary to obtain a significant reduction of mechanical convection.Trial Registration: Being a retrospective study, no trial registration was made.

A New Mapping Function for Spaceborne TEC Conversion Based on the Plasmaspheric Scale Height

The mapping function is crucial for the conversion of slant total electron content (TEC) to vertical TEC for low Earth orbit (LEO) satellite-based observations. Instead of collapsing the ionosphere into one single shell in commonly used mapping models, we defined a new mapping function assuming the vertical ionospheric distribution as an exponential profiler with one simple parameter: the plasmaspheric scale height in the zenith direction of LEO satellites. The scale height obtained by an empirical model introduces spatial and temporal variances into the mapping function. The performance of the new method is compared with the mapping function F&K by simulating experiments based on the global core plasma model (GCPM), and it is discussed along with the latitude, seasons, local time, as well as solar activity conditions and varying LEO orbit altitudes. The assessment indicates that the new mapping function has a comparable or better performance than the F&K mapping model, especially on the TEC conversion of low elevation angles.

Response to Comment on “Information arms race explains plant-herbivore chemical communication in ecological communities"

Zu et al. 2020 (1) proposed a simple, parameter-free, information-arms-race theory to explain the distributions of plant-herbivore interactions and plant-volatile associations observed in plant-herbivore communities. We received a comment by Bass and Kessler (Oct. 2020) questioning this theory and suggesting that a simpler neutral model can explain the observed distributions. This, with our response, went to peer review and was not published (Oct. 29, 2020). The authors have decided to publish their comment on EcoEvoRxiv (2) and so here, we are posting our reply. In sum, we present arguments to show that the comment from Bass and Kessler is based on an incorrect understanding of our study and furthermore suffers from circular reasoning, and that therefore their conclusions are not supported.

Response to Comment on “Information arms race explains plant-herbivore chemical communication in ecological communities”

Zu et al. 2020 (1) proposed a simple, parameter-free, information-arms-race theory to explain the distributions of plant-herbivore interactions and plant-volatile associations observed in plant-herbivore communities. We received a comment by Bass and Kessler (Oct. 2020) questioning this theory and suggesting that a simpler neutral model can explain the observed distributions. This, with our response, went to peer review and was not published (Oct. 29, 2020). The authors have decided to publish their comment on EcoEvoRxiv (2) and so here, we are posting our reply. In sum, we present arguments to show that the comment from Bass and Kessler is based on an incorrect understanding of our study and furthermore suffers from circular reasoning, and that therefore their conclusions are not supported.

Free manipulation system for nanorobot cluster based on complicated multi-coil electromagnetic actuator

Chemotherapy is an important method in the field of cancer treatment and often follows surgery and/or radiotherapy to remove as many tumor cells as possible. In particular, among the chemotherapy methods, treatment using electromagnetic-based actuation systems is considered an effective method owing to the remote control of nanorobots. The existing electromagnetic-based actuation systems, however, have certain disadvantages such as the lack of degrees of freedom and the difficulty of manipulating large numbers of nanorobots (i.e., nanorobot clusters). Herein, we report that nanorobot clusters can be manipulated with high degrees of freedom through a simple parameter alpha that easily controls the gradient of the magnetic field of a multi-coil electromagnetic actuation system. The simulation results show that the gradient of the magnetic field is controlled using an introduced parameter, alpha, and the corresponding velocity is also controlled. Not only the velocity of the nanorobot cluster but also the unrestricted spatial control is enabled in two- and three-dimensions. We believe this study highlights an efficient method of electromagnetic control for cluster-based drug delivery.

Random Forest-based Fingerprinting Technique for Device-free Indoor Localization System

The device-free indoor localization (DFIL) research is gaining attention due to the popularity of location-based service (LBS)-based advertisement. In DFIL, a user or an object does not need to bring any device to be localized. In this paper, we propose the Wi-Fi-based DFIL and the random forest algorithm for the fingerprint-based technique. The simple parameter commonly used in indoor localization is the Received Signal Strength Indicator (RSSI). We apply the fingerprint technique because of its reliability to handle the RSSI fluctuation and time-varying effect in a static indoor environment. We conducted an actual measurement campaign to observe the DFIL's implementation visibility. The DFIL system works by comparing the database fingerprint in an empty open office with the database in which a person is inside the measurement area without bringing any devices. Thus, we have the device-free RSSI database for fingerprint technique from both empty rooms and RSSI affected by a person inside the room. We validated the random forest algorithm results by comparing them with the k-nearest neighbor (kNN) and artificial neural network (ANN). The results show that our proposed system's accuracy is better than kNN and ANN with a mean error of 0.63 m than kNN with 0.80 m and ANN with 1.01 m. Meanwhile, the precision of the random forest is 0.63 m, whereas kNN and ANN are 0.67 m and 0.80 m, showing that the random forest performed better. We concluded that our simple DFIL system is visible to apply with acceptable accuracy performance.

Using simulation to predict reverberation room performance: Validation and parameter study

Predicting the behavior of a reverberation room is inherently challenging and often puzzling. Many still rely on a time-consuming trial-and-error approach when designing the interior and placing diffusers to achieve a diffuse field. An accurate finite element simulation of a reverberation room would enable design ideas and modifications to be tested without any downtime of the physical room. Room modifications of interest are diffuser geometry, material, size, and placement, and the addition of tuned absorbers. For a simulation to be capable of such a task, each surface would need to accurately emulate the material specific behaviors occurring in the room. A finite element simulation in Actran VI was tuned to reflect the real-world low-frequency behavior of the reverberation room at Blachford Acoustics located in West Chicago, IL. A detailed analysis of the process and methods used to create and verify the model are discussed. This is followed by a simple parameter study to look at some modifications of interest.

Ground State Energies of Helium-Like Ions Using a Simple Parameter-Free Matrix Method

This study aims to use hydrogenic orbitals within an analytic and numeric parameter-free truncated-matrix method to solve the projected Schrödinger equation of some Helium-like ions (3 ≤ Z ≤ 10). We also derived a new analytical expression of the ion ground state energies, which was simple and accurate and improved the accuracy of the analytic calculation, numerically using Mathematica. The standard matrix method was applied, where the wave function of the ions was expanded in a finite number of eigenvectors comprising hydrogenic orbitals. The Hamiltonian of the systems was calculated using the wave function and diagonalized to obtain their ground state energies. The results showed that a simple analytic expression of the ground state energies of He-like ions was successfully derived. Although the analytic expression was derived without involving any variational parameter, it was reasonably accurate with a 0.12% error for Ne8+ ion. From this method, the accuracy of the analytic energies was also numerically improved to 0.10% error for Ne8+ ion. The results clearly showed that the energies obtained using this method were more accurate than the hydrogenic perturbation theory and the uncertainty principle-variational approach. In addition, for Z > 4, our results were more accurate than those from the geometrical model.

Neutrophil-to-Lymphocyte Ratio and Covid-19 Symptom-based Severity at Admission

Background: Increased Neutrophil-to-Lymphocyte Ratio (NLR) is an independent risk factor for mortality in Covid-19 patients and is considered as an early warning sign of Covid-19 severity. This study aimed to observe the differences in NLR at admission between patients with mild, moderate, and severe symptoms of Covid-19 treated in a referral hospital in Banda Aceh, Indonesia.Methods: A total of 114 patients with Covid-19 admitted to a referral hospital in Banda Aceh, Indonesia, during March–September 2020 were included in this study. Demographic information and baseline laboratory data, including the NLR, were collected. Descriptive and inferential statistics were used to analyze the data. Results: The median NLR at admission was higher among patients with moderate to severe symptoms than those with mild symptoms [6.54 (2.80–97.00, IQR 4.81–9.44) vs 2.27 (0.79–5.07, IQR 1.43-2.98), p <0.001]. Covid-19 patients who died had a higher NLR than those who survived [10.88 (4.17–47.50, IQR 7.00–15.17) vs 6.15 (2.80–97.00, IQR 4.63–8.50), p 0.02]. Patients with moderate-severe symptoms had an initial NLR of 4.63–8.50 and decreased to 2.75–5.43 at the end of the treatment had a greater chance of survival. There was an increased probability of death in patients with moderate-severe symptoms whose initial NLR was 7.00–15.17, which was then elevated to 14.33–23.25.Conclusion: Different NLR at admission is seen among Covid-19 patients with mild and moderate-severe symptoms, leading to significantly different outcomes. The NLR can be used as a simple parameter to determine the severity of the disease and predict the outcome of Covid-19 patients.