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Optics Express Nov 2023Metasurfaces have enabled precise electromagnetic (EM) wave manipulation with strong potential to obtain unprecedented functionalities and multifunctional behavior in...
Metasurfaces have enabled precise electromagnetic (EM) wave manipulation with strong potential to obtain unprecedented functionalities and multifunctional behavior in flat optical devices. One promising aspect to achieve multifunction is polarization-dependent metadevices enabled by simultaneous phase control over orthogonally polarized waves. Among these, metasurfaces with geometric phase shows their natural and robust phase control ability over different circularly polarized waves. However, the phase responses under the circularly polarized incidence are locked to be opposite with each other, resulting in limited multifunctionality. In this study, we propose what we believe to be a novel transmission-type microwave metadevice constructed by linear-to-circular metasurface and spin-decoupled metasurface. By endowing independent phase adjustment capability to each unit structure in a spin-decoupled metasurface, the metadevice can reconfigure arbitrary phase wavefronts under orthogonal polarization state incidence, thereby achieving flexible multifunctionality. As a proof-of-concept, the feasibility and reliability of proposed metasurfaces were verified by simulating multifunctional directional deflection, off-axis focusing, and focused vortex beam generation. Finally, the multifunctional manipulation capability of the metadevice is successfully demonstrated by actually measuring the generation of orbital angular momentum modes. This work is expected to drive the application development of metasurface devices in wireless communication.
PubMed: 38041360
DOI: 10.1364/OE.505555 -
Bioinformatics (Oxford, England) Dec 2023statistics from genome-wide association studies enable many valuable downstream analyses that are more efficient than individual-level data analysis while also reducing... (Meta-Analysis)
Meta-Analysis
MOTIVATION
statistics from genome-wide association studies enable many valuable downstream analyses that are more efficient than individual-level data analysis while also reducing privacy concerns. As growing sample sizes enable better-powered analysis of gene-environment interactions, there is a need for gene-environment interaction-specific methods that manipulate and use summary statistics.
RESULTS
We introduce two tools to facilitate such analysis, with a focus on statistical models containing multiple gene-exposure and/or gene-covariate interaction terms. REGEM (RE-analysis of GEM summary statistics) uses summary statistics from a single, multi-exposure genome-wide interaction study to derive analogous sets of summary statistics with arbitrary sets of exposures and interaction covariate adjustments. METAGEM (META-analysis of GEM summary statistics) extends current fixed-effects meta-analysis models to incorporate multiple exposures from multiple studies. We demonstrate the value and efficiency of these tools by exploring alternative methods of accounting for ancestry-related population stratification in genome-wide interaction study in the UK Biobank as well as by conducting a multi-exposure genome-wide interaction study meta-analysis in cohorts from the diabetes-focused ProDiGY consortium. These programs help to maximize the value of summary statistics from diverse and complex gene-environment interaction studies.
AVAILABILITY AND IMPLEMENTATION
REGEM and METAGEM are open-source projects freely available at https://github.com/large-scale-gxe-methods/REGEM and https://github.com/large-scale-gxe-methods/METAGEM.
Topics: Gene-Environment Interaction; Genome-Wide Association Study; Models, Statistical; Sample Size; Data Interpretation, Statistical; Polymorphism, Single Nucleotide; Phenotype
PubMed: 38039147
DOI: 10.1093/bioinformatics/btad730 -
Journal, Genetic Engineering &... Nov 2023Factorial design is a simple, yet elegant method to investigate the effect of multiple factors and their interaction on a specific response simultaneously. Hence, this...
BACKGROUND
Factorial design is a simple, yet elegant method to investigate the effect of multiple factors and their interaction on a specific response simultaneously. Hence, this type of study design reaches the best optimization conditions of a process. Although the interaction between the variables is widely prevalent in cell culture procedures, factorial design per se is infrequently utilized in improving cell culture output. Therefore, we aim to optimize the experimental conditions for generating mature bone marrow-derived dendritic cells (BMDCs). Two different variables were investigated, including the concentrations of the inducing factors and the starting density of the bone marrow mononuclear cells. In the current study, we utilized the design of experiments (DoE), a statistical approach, to systematically assess the impact of factors with varying levels on cell culture outcomes. Herein, we apply a two-factor, two-level (2) factorial experiment resulting in four conditions that are run in triplicate. The two variables investigated here are cytokines combinations with two levels, granulocyte-macrophage colony-stimulating factor (GM-CSF) alone or with interleukin-4 (IL4). The other parameter is cell density with two different concentrations, 2 × 10 and 4 × 10 cells/mL. Then, we measured cell viability using the trypan blue exclusion method, and a flow cytometer was used to detect the BMDCs expressing the markers FITC-CD80, CD86, CD83, and CD14. BMDC marker expression levels were calculated using arbitrary units (AU) of the mean fluorescence intensity (MFI).
RESULTS
The current study showed that the highest total viable cells and cells yield obtained were in cell group seeded at 2 × 10 cells/mL and treated with GM-CSF and IL-4. Importantly, the expression of the co-stimulatory molecules CD83 and CD80/CD86 were statistically significant for cell density of 2 × 10 cells/mL (P < 0.01, two-way ANOVA). Bone marrow mononuclear cells seeded at 4 × 10 in the presence of the cytokine mix less efficiently differentiated and matured into BMDCs. Statistical analysis via two-way ANOVA revealed an interaction between cell density and cytokine combinations.
CONCLUSION
The analysis of this study indicates a substantial interaction between cytokines combinations and cell densities on BMDC maturation. However, higher cell density is not associated with optimizing DC maturation. Notably, applying DoE in bioprocess designs increases experimental efficacy and reliability while minimizing experiments, time, and process costs.
PubMed: 38017248
DOI: 10.1186/s43141-023-00597-4 -
Physica Medica : PM : An International... Dec 2023In NM-imaging, theoretical curves for the recovery coefficient (RC) of the signal maximum and mean are known for spheres and cubes, if a 3D Gaussian PSF is assumed. The...
BACKGROUND
In NM-imaging, theoretical curves for the recovery coefficient (RC) of the signal maximum and mean are known for spheres and cubes, if a 3D Gaussian PSF is assumed. The RC of the maximum is also known for cylinders. For these and other shapes empirical equations with one or two fit-parameters have been utilized.
METHODS
An equation for the RC for large objects of arbitrary shape is derived and generalized into an empirical equation for smaller objects, which is verified by numerical simulations. The proposed equation is compared to published results on SPECT kidney phantom measurements and to PET measurements on the NEMA IEC PET body phantom with six spheres.
RESULTS
The signal loss (1-RC) for large spheres is inversely proportional to the radius, where the slope is proportional to the FWHM of the spatial resolution. For non-spherical shapes the generalized instead of the volume equivalent radius should be utilized. For smaller objects, an equation with one added empirical fit-parameter is presented. It is demonstrated that the EANM-guidelines' two-parameter logistic function results in a poor fit if the theoretical slope and inverse proportionality are forced and it gives a suboptimal fit when both parameters are fitted.
CONCLUSIONS
A novel model-based equation for the mean RC-curve is derived. It can be used for arbitrary shapes as long as the sphericity is taken into account and it is accurate down to RC = 10 %. One parameter is directly related to the spatial resolution, while the other is a shape depending fit-parameter.
Topics: Positron-Emission Tomography; Tomography, X-Ray Computed; Phantoms, Imaging; Image Processing, Computer-Assisted
PubMed: 38007296
DOI: 10.1016/j.ejmp.2023.103174 -
Nanomedicine : Nanotechnology, Biology,... Feb 2024Flow cytometry allows to characterize nanoparticles (NPs) and extracellular vesicles (EVs) but results are often expressed in arbitrary units of fluorescence. We...
Flow cytometry allows to characterize nanoparticles (NPs) and extracellular vesicles (EVs) but results are often expressed in arbitrary units of fluorescence. We evaluated the precision and accuracy of molecules of equivalent soluble fluorophores (MESF) beads for calibration of NPs and EVs. Firstly, two FITC-MESF bead sets, 2 and 6 um in size, were measured on three flow cytometers. We showed that arbitrary units could not be compared between instruments but after calibration, comparable FITC MESF units were achieved. However, the two calibration bead sets displayed varying slopes that were consistent across platforms. Further investigation revealed that the intrinsic uncertainty related to the MESF beads impacts the robust assignment of values to NPs and EVs based on extrapolation into the dim fluorescence range. Similar variations were found with PE MESF calibration. Therefore, the same calibration materials and numbers of calibration points should be used for reliable comparison of submicron sized particles.
Topics: Calibration; Fluorescein-5-isothiocyanate; Flow Cytometry; Fluorescent Dyes; Extracellular Vesicles; Nanoparticles
PubMed: 38007067
DOI: 10.1016/j.nano.2023.102720 -
International Journal of Molecular... Nov 2023The selection of components within a formulation or for treatment must stop being arbitrary and must be focused on scientific evidence that supports the inclusion of...
Evaluation of the Antimicrobial Activity of a Formulation Containing Ascorbic Acid and Eudragit FS 30D Microparticles for the Controlled Release of a Curcumin-Boric Acid Solid Dispersion in Turkey Poults Infected with : A Therapeutic Model.
The selection of components within a formulation or for treatment must stop being arbitrary and must be focused on scientific evidence that supports the inclusion of each one. Therefore, the objective of the present study was to obtain a formulation based on ascorbic acid (AA) and Eudragit FS 30D microparticles containing curcumin-boric acid (CUR-BA) considering interaction studies between the active components carried out via Fourier transform infrared spectrometry (FTIR) and differential scanning calorimetry (DSC) to minimize antagonistic effects, and comprehensively and effectively treat turkey poults infected with (). The DSC and FTIR studies clearly demonstrated the interactions between AA, BA, and CUR. Consequently, the combination of AA with CUR and/or BA should be avoided, but not CUR and BA. Furthermore, the Eudragit FS 30D microparticles containing CUR-BA (SD CUR-BA MP) showed a limited release of CUR-BA in an acidic medium, but they were released at a pH 6.8-7.0, which reduced the interactions between CUR-BA and AA. Finally, in the infection model, turkey poults treated with the combination of AA and SD CUR-BA MP presented lower counts of in cecal tonsils after 10 days of treatment. These results pointed out that the use of an adequate combination of AA and CUR-BA as an integral treatment of infections could be a viable option to replace the indiscriminate use of antibiotics.
Topics: Animals; Curcumin; Salmonella enteritidis; Delayed-Action Preparations; Ascorbic Acid; Turkeys; Anti-Bacterial Agents
PubMed: 38003375
DOI: 10.3390/ijms242216186 -
Nature Communications Nov 2023Novel fundamental notions helping in the interpretation of the complex dynamics of nonlinear systems are essential to our understanding and ability to exploit them. In...
Novel fundamental notions helping in the interpretation of the complex dynamics of nonlinear systems are essential to our understanding and ability to exploit them. In this work we predict and demonstrate experimentally a fundamental property of Kerr-nonlinear media, which we name mode rejection and takes place when two intense counter-propagating beams interact in a multimode waveguide. In stark contrast to mode attraction phenomena, mode rejection leads to the selective suppression of a spatial mode in the forward beam, which is controlled via the counter-propagating backward beam. Starting from this observation we generalise the ideas of attraction and rejection in nonlinear multimode systems of arbitrary dimension, which paves the way towards a more general idea of all-optical mode control. These ideas represent universal tools to explore novel dynamics and applications in a variety of optical and non-optical nonlinear systems. Coherent beam combination in polarisation-maintaining multicore fibres is demonstrated as example.
PubMed: 38001059
DOI: 10.1038/s41467-023-42869-0 -
Scientific Reports Nov 2023Our goal was to investigate the effects of head-thorax elevation (HUP) during chest compressions (CC) on lung ventilation. A prospective study was performed on seven...
Our goal was to investigate the effects of head-thorax elevation (HUP) during chest compressions (CC) on lung ventilation. A prospective study was performed on seven human cadavers. Chest was automatically compressed-decompressed in flat position and during progressive HUP from 18 to 35°. Lung ventilation was measured with electrical impedance tomography. In each cadaver, 5 sequences were randomly performed: one without CC at positive end-expiratory pressure (PEEP) 0cmHO, 3 s with CC at PEEP0, 5 or 10cmHO and 1 with CC and an impedance threshold device at PEEP0cmHO. The minimal-to-maximal change in impedance (VT in arbitrary unit a.u.) and the minimal impedance in every breathing cycle (EELI) the) were compared between flat, 18°, and 35° in each sequence by a mixed-effects model. Values are expressed as median (1st-3rd quartiles). With CC, between flat, 18° and 35° VT decreased at each level of PEEP. It was 12416a.u. (10,689; 14,442), 11,239 (7667; 13,292), and 6457 (4631; 9516), respectively, at PEEP0. The same was true with the impedance threshold device. EELI/VT significantly decreased from - 0.30 (- 0.40; - 0.15) before to - 1.13 (- 1.70; - 0.61) after the CC (P = 0.009). With HUP lung ventilation decreased with CC as compared to flat position. CC are associated with decreased in EELI.
Topics: Humans; Prospective Studies; Respiration, Artificial; Positive-Pressure Respiration; Thorax; Electric Impedance; Cadaver; Lung
PubMed: 37989865
DOI: 10.1038/s41598-023-47727-z -
Nature Communications Nov 2023Safety-critical sensory applications, like medical diagnosis, demand accurate decisions from limited, noisy data. Bayesian neural networks excel at such tasks, offering...
Safety-critical sensory applications, like medical diagnosis, demand accurate decisions from limited, noisy data. Bayesian neural networks excel at such tasks, offering predictive uncertainty assessment. However, because of their probabilistic nature, they are computationally intensive. An innovative solution utilizes memristors' inherent probabilistic nature to implement Bayesian neural networks. However, when using memristors, statistical effects follow the laws of device physics, whereas in Bayesian neural networks, those effects can take arbitrary shapes. This work overcome this difficulty by adopting a variational inference training augmented by a "technological loss", incorporating memristor physics. This technique enabled programming a Bayesian neural network on 75 crossbar arrays of 1,024 memristors, incorporating CMOS periphery for in-memory computing. The experimental neural network classified heartbeats with high accuracy, and estimated the certainty of its predictions. The results reveal orders-of-magnitude improvement in inference energy efficiency compared to a microcontroller or an embedded graphics processing unit performing the same task.
PubMed: 37985669
DOI: 10.1038/s41467-023-43317-9 -
Nutrients Oct 2023A drinking strategy aiming to replace a given percentage of the sweat losses incurred during exercise should result in reproducible fluid intake volume and, hence, fluid...
A drinking strategy aiming to replace a given percentage of the sweat losses incurred during exercise should result in reproducible fluid intake volume and, hence, fluid balance from one exercise session to the other performed under similar scenarios. Whether this may also be the case with ad libitum drinking during exercise is unclear. We characterized the repeatability of ad libitum water intake during repeated 1 h exercise sessions and examined its effect over time on fluid balance and selected physiological functions and perceptual sensations. Twelve (3 women) healthy individuals participated in this study. At weekly intervals, they completed four 2 × 30 min walking/jogging exercise bouts (55% V˙O, 40 °C, 20-30% relative humidity) interspersed by a 3 min recovery period. During exercise, participants consumed water (20 °C) ad libitum. There were no significant differences among the four exercise sessions for absolute water intake volume (~1000 mL·h), percent body mass loss (~0.4%), sweat rate (~1300 mL·h) and percent of sweat loss replaced by water intake (~80%). Heart rate, rectal temperature, and perceived thirst and heat stress did not differ significantly between the first and fourth exercise sessions. Perceived exertion was significantly lower during the fourth vs. the first exercise session, but the difference was trivial (<1 arbitrary unit). In conclusion, ad libitum water intake during four successive identical 1 h walking/jogging sessions conducted in the heat will result in similar water intake volumes and perturbations in fluid balance, heart rate, rectal temperature, and perceived thirst, heat stress and exertion.
Topics: Female; Humans; Dehydration; Drinking; Hot Temperature; Jogging; Osmolar Concentration; Walking; Water-Electrolyte Balance; Male
PubMed: 37960153
DOI: 10.3390/nu15214500