409 research outputs found
Development of in vitro Chylomicron Assay Using Caco-2 Cells
Dietary fats are mainly transported by the intestine in lipoproteins: chylomicrons (CMs) and very low density lipoproteins (VLDLs). Unfortunately, studies of the intestinal absorption of dietary fat have been hampered by the lack of an adequate in vitro model system. As an in vitro model Caco-2 cells are able to secrete lipoproteins. We investigated the possible factors that may affect the secretion of CMs through the ultracentrifugation technique. The dose-dependent effects of oleic acid, mono-olein, egg lecithin, collagen matrix, and the effect of cell differentiation on CM secretion were then tested. We found that oleic acid, lecithin, and cell differentiation are critical for CM secretion by Caco-2 cells. To further confirm that our optimal condition is, in fact, favorable for efficient CM production, we compared it with control groups. We observed that our condition led to more efficient CM secretion as determined by the TGs, ApoB, and TEM analysis
Effects of Stirrups on Bond Behavior Between Concrete and Corroded Steel Bars
Steel corrosion leads to the deterioration of bond between concrete and steel bars. The serviceability and ultimate strength of concrete elements within RC structures are hence affected. Many researchers have studied the bond behavior of corroded steel bars. However, very few studies have investigated the effects of confinements on the degradation of bond strength. The present paper proposed a new kind of beam specimen based on which the effects of stirrups on degradation of bond were investigated. The test results proved that stirrups can effectively increase the bond strength between concrete and corroded steel bars
Clinical Assistant Diagnosis for Electronic Medical Record Based on Convolutional Neural Network
Automatically extracting useful information from electronic medical records
along with conducting disease diagnoses is a promising task for both clinical
decision support(CDS) and neural language processing(NLP). Most of the existing
systems are based on artificially constructed knowledge bases, and then
auxiliary diagnosis is done by rule matching. In this study, we present a
clinical intelligent decision approach based on Convolutional Neural
Networks(CNN), which can automatically extract high-level semantic information
of electronic medical records and then perform automatic diagnosis without
artificial construction of rules or knowledge bases. We use collected 18,590
copies of the real-world clinical electronic medical records to train and test
the proposed model. Experimental results show that the proposed model can
achieve 98.67\% accuracy and 96.02\% recall, which strongly supports that using
convolutional neural network to automatically learn high-level semantic
features of electronic medical records and then conduct assist diagnosis is
feasible and effective.Comment: 9 pages, 4 figures, Accepted by Scientific Report
Studying dawn-dusk asymmetries of Mercury's magnetotail using MHD-EPIC simulations
MESSENGER has observed a lot of dawn-dusk asymmetries in Mercury's
magnetotail, such as the asymmetries of the cross-tail current sheet thickness
and the occurrence of flux ropes, dipolarization events and energetic electron
injections. In order to obtain a global pictures of Mercury's magnetotail
dynamics and the relationship between these asymmetries, we perform global
simulations with the magnetohydrodynamics with embedded particle-in-cell
(MHD-EPIC) model, where Mercury's magnetotail region is covered by a PIC code.
Our simulations show that the dawnside current sheet is thicker, the plasma
density is larger, and the electron pressure is higher than the duskside. Under
a strong IMF driver, the simulated reconnection sites prefer the dawnside. We
also found the dipolarization events and the planetward electron jets are
moving dawnward while they are moving towards the planet, so that almost all
dipolarization events and high-speed plasma flows concentrate in the dawn
sector. The simulation results are consistent with MESSENGER observations
High Sensitivity Tunable Radio Frequency Sensors
Highly sensitive and tunable RF sensors that provide detection and analysis of single cells and particles are provided. The tunable RF sensors are configured as tunable interferometers, wherein cells or particles to be analyzed are passed through a channel, such as a microfluidic channel, across waveguides corresponding to reference and test branches of the interferometers. A network analyzer coupled to the interferometers can be configured to measure a plurality of scattering parameters, such as transmission scattering coefficients (S.sub.21) of the reference and test branches, to evaluate characteristics of cells passing through the channel. A plurality of tunable interferometers may be employed, each interferometer operating in different frequency bands such that information obtain from the plurality of interferometers may be combined to provide further information
Flexible Differentially Private Vertical Federated Learning with Adaptive Feature Embeddings
The emergence of vertical federated learning (VFL) has stimulated concerns
about the imperfection in privacy protection, as shared feature embeddings may
reveal sensitive information under privacy attacks. This paper studies the
delicate equilibrium between data privacy and task utility goals of VFL under
differential privacy (DP). To address the generality issue of prior arts, this
paper advocates a flexible and generic approach that decouples the two goals
and addresses them successively. Specifically, we initially derive a rigorous
privacy guarantee by applying norm clipping on shared feature embeddings, which
is applicable across various datasets and models. Subsequently, we demonstrate
that task utility can be optimized via adaptive adjustments on the scale and
distribution of feature embeddings in an accuracy-appreciative way, without
compromising established DP mechanisms. We concretize our observation into the
proposed VFL-AFE framework, which exhibits effectiveness against privacy
attacks and the capacity to retain favorable task utility, as substantiated by
extensive experiments
2,5-Bis[(3-hydroxypropyl)amino]-1,4-benzoquinone monohydrate
The title compound, C12H18N2O4·H2O, was obtained as a product of the reaction of hydroquinone with n-propanol amine. The compound crystallizes as a monohydrate, integrating water into its hydrogen-bonded network. Each diaminoquinone moiety forms two centrosymmetric 10-membered rings through C=O⋯H—N bonds. The resulting bands along [102] are interlinked through hydroxy groups and water molecules into three-dimensional network. The chemically equivalent bond lengths in the diaminoquinone moiety exhibit a perceptible discrepancy [e.g. C=O bond lengths differ by 0.016 (2) Å], apparently as a result of asymmetric hydrogen bonding: one O atom serves as an acceptor of one hydrogen bond, whereas the other is an acceptor of two
Chylomicrons Produced by Caco-2 Cells Contained ApoB-48 with Diameter of 80-200 nm
The small intestine generally transports dietary fats to circulation in triglyceride (TG)-rich lipoproteins. The two main intestinal lipoproteins are chylomicron (CM) and very low-density lipoprotein (VLDL). Unfortunately, studies on the CM biogenesis and intestinal transport of dietary fats have been hampered by the lack of an adequate in vitro model. In this study, we investigated the possible factors that might increase the efficiency of CM production by Caco-2 cells. We utilized sequential NaCl gradient ultracentrifugation to isolate the CMs that were secreted by the Caco-2 cells. To confirm the successful isolation of the CMs, we performed Fat Red 7B staining, TG reading, apolipoprotein B (ApoB) measurement, and transmission electron microcopy (TEM) analysis. We then tested the effects of cell differentiation, oleic acid, mono-olein, egg lecithin, incubation time, and collagen matrix on CM secretion. We found that cell differentiation, oleic acid, and lecithin were critical for CM secretion. Using the Transwell system, we further confirmed that the CMs produced by our Caco-2 cells contained significant amount of TGs and ApoB-48 such that they could be detected without the use of isotope labeling. In conclusion, when fully differentiated Caco-2 were challenged with oleic acid, lecithin, and sodium taurocholate, 21% of their total number of lipoproteins were CMs with the diameter of 80-200 nm
Chylomicrons Produced by Caco-2 Cells Contained ApoB-48 With Diameter of 80-200 nm
The small intestine generally transports dietary fats to circulation in triglyceride (TG)-rich lipoproteins. The two main intestinal lipoproteins are chylomicron (CM) and very low-density lipoprotein (VLDL). Unfortunately, studies on the CM biogenesis and intestinal transport of dietary fats have been hampered by the lack of an adequate in vitro model. In this study, we investigated the possible factors that might increase the efficiency of CM production by Caco-2 cells. We utilized sequential NaCl gradient ultracentrifugation to isolate the CMs that were secreted by the Caco-2 cells. To confirm the successful isolation of the CMs, we performed Fat Red 7B staining, TG reading, apolipoprotein B (ApoB) measurement, and transmission electron microcopy (TEM) analysis. We then tested the effects of cell differentiation, oleic acid, mono-olein, egg lecithin, incubation time, and collagen matrix on CM secretion. We found that cell differentiation, oleic acid, and lecithin were critical for CM secretion. Using the Transwell system, we further confirmed that the CMs produced by our Caco-2 cells contained significant amount of TGs and ApoB-48 such that they could be detected without the use of isotope labeling. In conclusion, when fully differentiated Caco-2 were challenged with oleic acid, lecithin, and sodium taurocholate, 21% of their total number of lipoproteins were CMs with the diameter of 80-200 nm
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