Modeling of polyethylene, poly(l-lactide), and CNT composites: a dissipative particle dynamics study

Dissipative particle dynamics (DPD), a mesoscopic simulation approach, is used to investigate the effect of volume fraction of polyethylene (PE) and poly(l-lactide) (PLLA) on the structural property of the immiscible PE/PLLA/carbon nanotube in a system. In this work, the interaction parameter in DPD simulation, related to the Flory-Huggins interaction parameter χ, is estimated by the calculation of mixing energy for each pair of components in molecular dynamics simulation. Volume fraction and mixing methods clearly affect the equilibrated structure. Even if the volume fraction is different, micro-structures are similar when the equilibrated structures are different. Unlike the blend system, where no relationship exists between the micro-structure and the equilibrated structure, in the di-block copolymer system, the micro-structure and equilibrated structure have specific relationships

Marching velocity of capillary meniscuses in microchannels

[[abstract]]This paper describes a new method and an analytical model for characterizing the surface energy inside a microchannel using the measurement of the marching velocity of a capillary meniscus. This method is based on the fact that surface tension of a liquid meniscus in a hydrophilic case produces pressure to pull liquid into the channel and the velocity of the meniscus is related to the surface energy. Both Parylene and silicon nitride microchannels with different surface conditions were fabricated to perform the liquid-filling experiments. It is shown that our model agrees well with the data and this is a valid method.[[conferencetype]]國際[[conferencedate]]20020120~20020124[[iscallforpapers]]Y[[conferencelocation]]Las Vegas, NV, US

Operative Treatment of Intra-articular Distal Radius Fractures Using the Small AO External Fixation Device

BackgroundA retrospective group study was done to evaluate the effect of the small AO external fixator in the management of acute intra-articular fractures of the distal radius.MethodsBetween January 1995 and December 1996, 70 consecutive patients with articular fractures of the distal radius were treated by closed reduction and external fixation with small AO external fixators. The mean age at the time of surgery was 58.9 years (range, 14–87 years). There were 58 Colles' Barton's fractures and 12 Smith's Barton's fractures. The follow-up period was 104 months (range, 92–118 months).ResultsAll fractures united in a mean of 5.8 weeks (range, 4–10 weeks). At the final follow-up, the average range of motion was 56.3 ± 11.6° in flexion, 58.6 ± 10.7° in extension, 21.5 ± 4.2° in ulnar deviation, 9.1 ± 2.9° in radial deviation, 71.5 ± 8.5° in pronation, and 67.3 ± 9.2° in supination. Compared with the normal side, the average grip force was 87 ± 6%. The overall clinical and functional outcomes, according to the scoring system of Gartland and Werley, showed that 22 patients (31.4%) had excellent results, 36 (51.4%) had good results, 9 (12.9%) had fair results, and 3 (4.3%) had poor results.ConclusionClosed reduction and external fixation with the small AO external fixator is useful and effective in the management of displaced comminuted articular fractures of the distal radius

Comparison of the Offspring Sex Ratio Between Cleavage Stage Embryo Transfer and Blastocyst Transfer

SummaryObjectiveTo compare the sex ratio of offspring born after cleavage stage embryo transfer and blastocyst transfer.Materials and MethodsIn this retrospective study of embryo transfer (ET), we included 473 offspring from 446 deliveries during the period January 2002 to December 2007. Statistical analysis was performed on the sex ratio of offspring resulting from day 3 cleavage stage embryo transfer and from sequential blastocyst culture transfer.ResultsIn total, 446 patient deliveries were included in this analysis. There were 251 singleton pregnancies, 109 twin pregnancies, and four triplet pregnancies. The total number of offspring was 473, of which 118 resulted from day 3 ETs, and 355 resulted from blastocyst ETs. At our center, the influence on the sex ratio of cleavage stage ET and blastocyst-stage ET showed a bias towards males in both cases. The overall female to male ratio for offspring resulting from day 3 ETs was not significantly higher than the same ratio for offspring resulting from blastocyst ETs (p = 0.24; odds ratio, 0.762). The female to male ratio for either singleton births or multiple deliveries was also not significantly different between day 3 ETs and blastocyst ETs.ConclusionThe sex ratio was influenced by cleavage stage ET and blastocyst-stage ET. In both cases, there was a bias towards males. In addition, when blastocyst ET was compared with day 3 ET, there was no further increase in the percentage of male offspring

Differential Cytotoxicity Induced by Transition Metal Oxide Nanoparticles is a Function of Cell Killing and Suppression of Cell Proliferation

The application of nanoparticles (NPs) in industry is on the rise, along with the potential for human exposure. While the toxicity of microscale equivalents has been studied, nanoscale materials exhibit different properties and bodily uptake, which limits the prediction ability of microscale models. Here, we examine the cytotoxicity of seven transition metal oxide NPs in the fourth period of the periodic table of the chemical elements. We hypothesized that NP-mediated cytotoxicity is a function of cell killing and suppression of cell proliferation. To test our hypothesis, transition metal oxide NPs were tested in a human lung cancer cell model (A549). Cells were exposed to a series of concentrations of TiO2, Cr2O3, Mn2O3, Fe2O3, NiO, CuO, or ZnO for either 24 or 48 h. All NPs aside from Cr2O3 and Fe2O3 showed a time-and dose-dependent decrease in viability. All NPs significantly inhibited cellular proliferation. The trend of cytotoxicity was in parallel with that of proliferative inhibition. Toxicity was ranked according to severity of cellular responses, revealing a strong correlation between viability, proliferation, and apoptosis. Cell cycle alteration was observed in the most toxic NPs, which may have contributed to promoting apoptosis and suppressing cell division rate. Collectively, our data support the hypothesis that cell killing and cell proliferative inhibition are essential independent variables in NP-mediated cytotoxicity

New Plasma Separation Glucose Oxidase-based Glucometer in Monitoring of Blood With Different PO2 Levels

BackgroundThe PalmLab glucometer is a newly designed plasma separation glucose oxidase (GO)-based glucometer. Past studies have shown that the accuracy of GO-based glucometers is compromised when measurements are taken in patients with high PO2 levels. We performed a two-arm study comparing the fitness of the PalmLab blood glucometer with that of a standard glucose analyzer in monitoring blood glucose levels in pediatric patients, especially when arterial partial pressure of oxygen (PO2) was high.MethodsIn the first arm of the study, arterial blood samples from pediatric patients were measured by the PalmLab blood glucometer and the YSI 2302 Plus Glucose/Lactate analyzer. In the second arm of the study, venous blood samples from adult volunteers were spiked with glucose water to prepare three different levels of glucose (65, 150, and 300mg/dL) and then oxygenated to six levels of PO2 (range, 40–400mmHg). The biases of the PalmLab glucometer were calculated.ResultsA total of 162 samples were collected in the first arm of the study. Results of linear regression showed that the coefficient of determination (R2) between PalmLab glucometer and standard glucose analyzer was 0.9864. Error grid analysis revealed that all the results were within Zone A (clinically accurate estimate zone). The biases between the two systems were low at different PO2 levels. In the second arm of the study, the results were also unaffected by changes in PO2.ConclusionThe PalmLab glucometer provides accurate results in samples with high PO2 and is suitable for measuring arterial glucose levels in pediatric patients

Functional annotation of proteomic data from chicken heterophils and macrophages induced by carbon nanotube exposure

With the expanding applications of carbon nanotubes (CNT) in biomedicine and agriculture, questions about the toxicity and biocompatibility of CNT in humans and domestic animals are becoming matters of serious concern. This study used proteomic methods to profile gene expression in chicken macrophages and heterophils in response to CNT exposure. Two-dimensional gel electrophoresis identified 12 proteins in macrophages and 15 in heterophils, with differential expression patterns in response to CNT co-incubation (0, 1, 10, and 100 µg/mL of CNT for 6 h) (p < 0.05). Gene ontology analysis showed that most of the differentially expressed proteins are associated with protein interactions, cellular metabolic processes, and cell mobility, suggesting activation of innate immune functions. Western blot analysis with heat shock protein 70, high mobility group protein, and peptidylprolyl isomerase A confirmed the alterations of the profiled proteins. The functional annotations were further confirmed by effective cell migration, promoted interleukin-1β secretion, and more cell death in both macrophages and heterophils exposed to CNT (p < 0.05). In conclusion, results of this study suggest that CNT exposure affects protein expression, leading to activation of macrophages and heterophils, resulting in altered cytoskeleton remodeling, cell migration, and cytokine production, and thereby mediates tissue immune responses

Strong Gravitational Lensing Parameter Estimation with Vision Transformer

Quantifying the parameters and corresponding uncertainties of hundreds of strongly lensed quasar systems holds the key to resolving one of the most important scientific questions: the Hubble constant ($H_{0}$) tension. The commonly used Markov chain Monte Carlo (MCMC) method has been too time-consuming to achieve this goal, yet recent work has shown that convolution neural networks (CNNs) can be an alternative with seven orders of magnitude improvement in speed. With 31,200 simulated strongly lensed quasar images, we explore the usage of Vision Transformer (ViT) for simulated strong gravitational lensing for the first time. We show that ViT could reach competitive results compared with CNNs, and is specifically good at some lensing parameters, including the most important mass-related parameters such as the center of lens $\theta_{1}$ and $\theta_{2}$, the ellipticities $e_1$ and $e_2$, and the radial power-law slope $\gamma'$. With this promising preliminary result, we believe the ViT (or attention-based) network architecture can be an important tool for strong lensing science for the next generation of surveys. The open source of our code and data is in \url{https://github.com/kuanweih/strong_lensing_vit_resnet}.Comment: Accepted by ECCV 2022 AI for Space Worksho