The effects of different complex refractive indices of underwater suspended particles on the polarization characteristics of forward and backward scattering of polarized photons are analyzed by ...simulation experiments to study the transmission characteristics of polarized light as influenced by underwater suspended particles. The Mie scattering theory is used to establish the scattering model of underwater photon transmission. The Mueller matrix and Meridian Planes Monte Carlo method are adopted to simulate the process of photon radiation transmission in the scattering medium. Simulation results show that the polarization degree of the scattered linearly polarized light is less affected than the scattered circularly polarized light by the refractive index parameter in the scattering system. As the absorption coefficient increases, the polarization-maintaining ability of the forward scattered linearly polarized light is enhanced, whereas the degree of circular polarization of the backward scattered circularly polarized light is periodically changed.
The perijunctional actomyosin ring contributes to myosin light chain kinase (MLCK)-dependent tight junction regulation. However, the specific protein interactions involved in this process are ...unknown. To test the hypothesis that molecular remodeling contributes to barrier regulation, tight junction protein dynamic behavior was assessed by fluorescence recovery after photobleaching (FRAP). MLCK inhibition increased barrier function and stabilized ZO-1 at the tight junction but did not affect claudin-1, occludin, or actin exchange in vitro. Pharmacologic MLCK inhibition also blocked in vivo ZO-1 exchange in wild-type, but not long MLCK⁻/⁻, mice. Conversely, ZO-1 exchange was accelerated in transgenic mice expressing constitutively active MLCK. In vitro, ZO-1 lacking the actin binding region (ABR) was not stabilized by MLCK inhibition, either in the presence or absence of endogenous ZO-1. Moreover, the free ABR interfered with full-length ZO-1 exchange and reduced basal barrier function. The free ABR also prevented increases in barrier function following MLCK inhibition in a manner that required endogenous ZO-1 expression. In silico modeling of the FRAP data suggests that tight junction-associated ZO-1 exists in three pools, two of which exchange with cytosolic ZO-1. Transport of the ABR-anchored exchangeable pool is regulated by MLCK. These data demonstrate a critical role for the ZO-1 ABR in barrier function and suggest that MLCK-dependent ZO-1 exchange is essential to this mechanism of barrier regulation.
An analytical and closed-form optimal solution expressed in elementary functions for superdirectivity of a circular sensor array is proposed in this paper. By utilizing the circulant property of the ...data covariance matrix for circular sensor arrays, such solutions are derived to accurately calculate the optimal beamforming vector, optimal beam pattern, corresponding directivity factor, and eigenbeams. Based on these solutions, it is proved that such array possesses several important properties which facilitate an eigenbeam decomposition and synthesis approach for practical implementations. Experiments conducted result in superdirective beams which contain zeroth- to fifth- and sixth-order eigenbeams. As a typical result, the superdirective beam which contains zeroth- to fifth-order eigenbeams has a 28 ° beamwidth and a 12-dB directivity index with a small circular array radius of 0.267 wavelength.
Although the C-terminal cytoplasmic tail of the tight junction protein occludin is heavily phosphorylated, the functional impact of most individual sites is undefined. Here, we show that inhibition ...of CK2-mediated occludin S408 phosphorylation elevates transepithelial resistance by reducing paracellular cation flux. This regulation requires occludin, claudin-1, claudin-2, and ZO-1. S408 dephosphorylation reduces occludin exchange, but increases exchange of ZO-1, claudin-1, and claudin-2, thereby causing the mobile fractions of these proteins to converge. Claudin-4 exchange is not affected. ZO-1 domains that mediate interactions with occludin and claudins are required for increases in claudin-2 exchange, suggesting assembly of a phosphorylation-sensitive protein complex. Consistent with this, binding of claudin-1 and claudin-2, but not claudin-4, to S408A occludin tail is increased relative to S408D. Finally, CK2 inhibition reversed IL-13-induced, claudin-2-dependent barrier loss. Thus, occludin S408 dephosphorylation regulates paracellular permeability by remodeling tight junction protein dynamic behavior and intermolecular interactions between occludin, ZO-1, and select claudins, and may have therapeutic potential in inflammation-associated barrier dysfunction.
Abstract
Background
Arbas Cashmere goats are excellent domestic breeds with high yields of wool and cashmere. Their wool and cashmere can bring huge benefits to the livestock industry. Our studies ...intend to more fully understand the biological characteristics of hair follicle stem cells (HFSCs) in order to further explore the mechanisms of wool and cashmere regular regeneration. And they have been increasingly considered as promising multipotent cells in regenerative medicine because of their capacity to self
-
renew and differentiate. However, many aspects of the specific growth characteristics and differentiation ability of HFSCs remain unknown. This study aimed to further explore the growth characteristics and pluripotency of primary hair follicle stem cells (PHFSCs) and secondary hair follicle stem cells (SHFCs).
Results
We obtained PHFSCs and SHFSCs from Arbas Cashmere goats using combined isolation and purification methods. The proliferation and vitality of the two types of HFSCs, as well as the growth patterns, were examined. HFSC
-
specific markers and genes related to pluripotency, were subsequently identified. The PHFSCs and SHFSCs of Arbas Cashmere goat have a typical cobblestone morphology. Moreover, the PHFSCs and SHFSCs express HFSC surface markers, including
CD34
,
K14
,
K15
,
K19
and
LGR5
. We also identified pluripotency
-
associated gene expression, including
SOX2
,
OCT4
and
SOX9
, in PHFSCs and SHFSCs. Finally, PHFSCs and SHFSCs displayed multipotent abilities. PHFSCs and SHFSCs can be directed to differentiate into adipocyte
-
like, neural
-
like, and hepatocyte
-
like cells.
Conclusions
In conclusion, this study confirmed that the biological characteristics and differentiation potential of PHFSCs and SHFSCs from Arbas Cashmere goats. These findings broaden and refine our knowledge of types and characteristics of adult stem cells.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Source localization in underwater sensor networks (UWSNs) presents complex challenges due to sensor nodes drift caused by ocean currents, non-line-of-sight (NLOS) propagation resulting from ...underwater multipath effects, and environmental noise. This paper proposes a practical and innovative algebraic solution based on the time difference of arrival (TDOA) for source localization in shallow seas. The proposed solution effectively addresses the issues arising from sensor position errors and multipath effects by incorporating the sea-surface reflection non-line-of-sight (SNLOS) link and optimizing the algorithm, thereby significantly improving positioning accuracy. The core concept of the method involves utilizing the weighted least squares algorithm to obtain an initial estimate of the source position, followed by direct estimation of the bias and subsequent refinement of the solution. In contrast to traditional closed-form solutions, this method avoids the introduction of intermediate parameters and directly handles the estimated bias from the previous step. Even when only considering the line-of-sight (LOS) link, the proposed solution achieves precise localization with a minimal number of sensors. Theoretical analysis demonstrates that the solution can achieve the Cramér–Rao lower bound (CRLB) accuracy under low noise conditions, and simulation results validate the superior performance of the proposed solution.
Utilizing newly acquired 3D seismic data, piston core, bathymetry and wells, this study investigated the geomorphological characters, genesis and evolution of two main phases of Quaternary mass ...transport deposits (MTDs) in the Pearl River canyon's middle segment. The older MTDs_1 almost covers the whole trough zone of Pearl River canyon's middle segment with an area of 1570 km2, which is sourced from north, west and south. Whereas the younger MTDs_2 has a much smaller coverage area of 840 km2 and is mainly from the northern slope. These MTDs could be divided into western and northern slope-attached MTDs and southern slope-detached MTDs based on their source areas. Within the MTDs-dominated study area, coarse sediments are presented at the area connecting to the slope channels and canyons. These two phases of MTDs probably occurred at ∼0.79 Ma and ∼0.54 Ma according to a published dating result. The homogeneous, organic-rich fine-grained sediments have high compressibility, preconditioning the generation of weak layers for submarine failures on the low gradient slope in the Pearl River canyon's middle segment.
Our results showed that slope canyon types, variations of sediment supply and the regional tectonic evolution exerted important controls on the generation and evolution of these MTDs. The eastern slope canyons with little slope fans have a steeper slope at the canyon mouths, resulting the northeastern MTDs to be prone to retrograde landwards. The change of shelf-channel system from un-incised type to incised type increased the sediment delivery efficiency, resulting in larger scale MTDs_1 in the Pearl River canyon. While the subsequent decrease in the number of incised shelf channels cut down the sediment delivery into the deep-water and reduced the younger MTDs' scale as well. The variation of sediment supply had a greater impact on the development of slope-attached MTDs. The rapid subsidence of Baiyun Sag and tectonic activities of Dongsha Rise during the Quaternary favored the occurrence of the submarine landslides on low gradient slopes in the study area. However, the weakening of the tectonic activities resulted the Quaternary MTDs’ scale to be decreased upwards, especially for the southern slope-detached MTDs. The complex topography formed by the slope-attached MTDs has a greater potential to capture the subsequent turbidity currents from the shelf-edge deltas, bringing the generation of potential good turbidite reservoirs in the deep-water region.
•The sedimentary features of the mass transport deposits (MTDs) are displayed.•The spatial distribution and evolution of the MTDs are discerned.•The controls on the genesis and evolution of the Quaternary MTDs are revealed.•Implication on the formation of MTDs-related turbidite reservoir is proposed.
Underwater acoustic localization (UWAL) is extremely challenging due to the multipath nature of extreme underwater environments, the sensor position uncertainty caused by unpredictable ocean ...currents, and the lack of underwater observation data due to sparse array, which all affect localization performance. Addressing these issues, this paper proposes a simple and effective underwater acoustic localization method using the time difference of arrival (TDOA) measurements based on the multipath channel effect of the underwater environment. By introducing the calibration source, localization performance was improved, and the sensor position error was corrected. The Cramér–Rao lower bound (CRLB) was derived, and the proposed method was able to achieve the CRLB with small deviation. Numerical simulations confirm the improved performance of the proposed method, including (1) a 20 dB and 30 dB reduction in the CRLB for far and near source scenarios, respectively, indicating improved accuracy and reliability when estimating unknown sources; (2) better Mean Squared Error (MSE) performance compared to existing methods and an efficiency of over 90% in low noise and above 80% in moderate noise in several scenarios, with a delayed threshold effect; and (3) achieving CRLB performance with only three sensors in a 3D space, even under moderate noise, while existing methods require at least five sensors for comparable performance. Our results demonstrate the efficacy of the proposed method in enhancing the accuracy and efficiency of source localization.
In this article, we study a class of fractional Kirchhoff with a superlinear nonlinearity:
<disp-formula> <tex-math id="FE1"> \begin{document}$ \begin{equation} \begin{cases} ...M(\int_{\mathbb{R}^{N}}|(-\triangle)^{\frac{\alpha}{2}}u|^{2}dx)(-\triangle)^{\alpha}u+\lambda V(x)u = f(x, u)\; \; \mbox{in}\; \; \mathbb{R}^{N}, \\ u\in H^{\alpha}(\mathbb{R}^{N}), \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; \; N\geq1, \; \; \; \; \; \; \; \; (1.1)\notag \end{cases} \end{equation} $\end{document} </tex-math></disp-formula>
where $ \lambda > 0 $ is a parameter, $ a $ and $ b $ are positive numbers satisfying $ M(t) = am(t)+b $, $ m:\mathbb{R}^{+}\rightarrow \mathbb{R}^{+} $ is continuous. $ V: \mathbb{R}^{N}\times\mathbb{R}\rightarrow \mathbb{R} $ is continuous. $ f $ satisfies $ \lim\limits_{|t|\rightarrow \infty}f(x, t)/|t|^{k-1} = Q(x) $ uniformly in $ x\in\mathbb{R}^{N} $ for each $ 2 < k < 2_{\alpha}^{\ast}, (2_{\alpha}^{\ast} = \frac{2N}{N-2\alpha}) $. We investigated the effects of functions $ m $ and $ Q $ on the solution. By applying the variational method, we obtain the existence of multiple solutions. Furthermore, it is worth mentioning that the ground state solution has also been obtained.
PDF
