The optical performance of the human cornea under intraocular pressure (IOP) is the result of complex material properties and their interactions. The measurement of the numerous material parameters that define this material behavior may be key in the refinement of patient-specific models. The goal of this study was to investigate the relative contribution of these parameters to the biomechanical and optical responses of human cornea predicted by a widely accepted anisotropic hyperelastic finite element model, with regional variations in the alignment of fibers. Design of experiments methods were used to quantify the relative importance of material properties including matrix stiffness, fiber stiffness, fiber nonlinearity and fiber dispersion under physiological IOP. Our sensitivity results showed that corneal apical displacement was influenced nearly evenly by matrix stiffness, fiber stiffness and nonlinearity. However, the variations in corneal optical aberrations (refractive power and spherical aberration) were primarily dependent on the value of the matrix stiffness. The optical aberrations predicted by variations in this material parameter were sufficiently large to predict clinically important changes in retinal image quality. Therefore, well-characterized individual variations in matrix stiffness could be critical in cornea modeling in order to reliably predict optical behavior under different IOPs or after corneal surgery.
Three
novel organic dyes coded as FHD4, FHD5,
and FHD6 featuring spiro[dibenzo[3,4:6,7]cyclohepta[1,2-b]quinoxaline-10,9′-fluorene] (SDBQX) moieties were developed for dye-sensitized solar cells (DSSCs).
The fluorenyl moiety of SDBQX is perpendicular to the
quinoxaline moiety, which is beneficial in inhibiting the H-aggregation
in DSSCs. The band gap energies according to DFT calculations showed
a good correlation with the transition energy calculated from the
absorption spectra, which indicates that the DFT calculations would
be an effective method to predict the absorption spectra range for FHD-type dyes. Broad spectral coverage and a high molar extinction
were observed in the absorption spectrum of FHD4, which
leads to the best power conversion efficiency that was obtained for
the FHD4-based DSSC. Coadsorption of CDCA improved the
power conversion efficiency slightly for FHD4-based DSSCs
(from 4.61 to 4.69%) and FHD6-based DSSCs (from 3.59
to 3.69%). The coadsorption of CDCA decreased the dye loading amount
of FHD5 significantly, while the power conversion efficiency
increased significantly from 3.18 to 3.73%. Finally, we have developed SDBQX as a new architecture for developing efficient organic
dyes for DSSC applications.
As typical perfluorinated compounds (PFCs), perfluorooctanoic
acid
(PFOA) and perfluorooctane sulfonate (PFOS) have been detected in
various environmental media and their toxic effects have been extensively
studied. Nevertheless, it remains unclear how PFCs cause cell apoptosis
in healthy hepatocytes by inducing oxidative stress at the subcellular
and molecular levels. In this study, the apoptotic pathways induced
by PFOA and PFOS were explored. Besides, the effects of PFCs on the
structure and function of lysozyme (LYZ) were investigated. After
PFOA and PFOS exposure, the cell membrane and mitochondrial membrane
potential were damaged. Further, PFOA and PFOS increased intracellular
Ca2+ levels to 174.41 ± 1.70 and 158.91 ± 5.94%,
respectively. Ultimately, caspase-3 was activated, causing cell apoptosis.
As an indirect antioxidant enzyme, the molecular structure of LYZ was
destroyed after interacting with PFOA and PFOS. Both PFOA and PFOS
bound to the active center of LYZ, leading to the decrease of LYZ
activity to 91.26 ± 0.78 and 76.01 ± 4.86%, respectively.
This study demonstrates that PFOA and PFOS inhibit LYZ function, which
can reduce the body’s ability to resist oxidative stress, and
then lead to mitochondria-mediated apoptosis.
Whole body vibration (WBV) is a non-invasive physical therapy that has recently been included in the hospital's patient rehabilitation training catalog, but its health effects have not been sufficiently studied. In the present study, to examine the possible effects of WBV on immune cell differentiation, the IFN, IL-4,−17, F4/80 and CD3,−4,−8,−11b,−11c,−19 markers were used to characterizing the cells in mouse spleen. The results showed that the CD4 and CD25 positive lymphocytes in the spleen were significantly increased in the WBV group, and the population of Treg cells was enhanced significantly in response to WBV. Since the differentiation in immune cells is usually associated with microbiota, therefore the intestinal flora was characterized in mice and human individuals. The results indicated that WBV significantly reduced the α-diversity of mouse intestinal microbiota. Moreover, the principal coordinate analysis (PCoA) results indicated that the β-diversities of both mice and human fecal microbiota increased after WBV. Analysis of the bacterial composition indicated that the contents of a variety of bacteria changed in mice upon the stimulation of vibration, such as Lactobacillus animalis in mice, and Lactobacillus paraplantarum and Lactobacillus sanfranciscensis in human. The succeeding correlation analysis revealed that some bacteria with significant content variations were correlated to the regulatory T cell differentiation in mice and physical characteristics in human. Our research will provide the basis for future non-invasive treatment of microbial and immune related diseases.
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