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Paxillin facilitates timely neurite initiation on soft-substrate environments by interacting with the endocytic machinery.
Neurite initiation is the first step in neuronal development and occurs spontaneously in soft tissue environments. Although the mechanisms regulating the morphology of migratory cells on rigid substrates in cell culture are widely known, how soft environments modulate neurite initiation remains elusive. Using hydrogel cultures, pharmacologic inhibition, and genetic approaches, we reveal that paxillin-linked endocytosis and adhesion are components of a bistable switch controlling neurite initiation in a substrate modulus-dependent manner. On soft substrates, most paxillin binds to endocytic factors and facilitates vesicle invagination, elevating neuritogenic Rac1 activity and expression of genes encoding the endocytic machinery. By contrast, on rigid substrates, cells develop extensive adhesions, increase RhoA activity and sequester paxillin from the endocytic machinery, thereby delaying neurite initiation. Our results highlight paxillin as a core molecule in substrate modulus-controlled morphogenesis and define a mechanism whereby neuronal cells respond to environments exhibiting varying mechanical properties
A Decision Support System for Planning And Design Tender Selection in Public Buildings
This paper presents an integrated system in which a knowledge-based decision support system (DSS) for selecting planning and design (P&D) tenders in public building construction. The Analytic Hierarchy Process (AHP) method is used to determine the weightings for evaluation criteria among decision makers and Fuzzy Multiple Criteria Decision Making (FMCDM) is dealt with the subjectivity and vagueness in the tender selection process. A case study consisting of nine alternatives, solicited from a public works agency in Taiwan, illustrates the effectiveness of the proposed approach and developed system
Cholinergic Circuits Integrate Neighboring Visual Signals in a Drosophila Motion Detection Pathway
SummaryDetecting motion is a feature of all advanced visual systems [1], nowhere more so than in flying animals, like insects [2, 3]. In flies, an influential autocorrelation model for motion detection, the elementary motion detector circuit (EMD; [4, 5]), compares visual signals from neighboring photoreceptors to derive information on motion direction and velocity. This information is fed by two types of interneuron, L1 and L2, in the first optic neuropile, or lamina, to downstream local motion detectors in columns of the second neuropile, the medulla. Despite receiving carefully matched photoreceptor inputs, L1 and L2 drive distinct, separable pathways responding preferentially to moving “on” and “off” edges, respectively [6, 7]. Our serial electron microscopy (EM) identifies two types of transmedulla (Tm) target neurons, Tm1 and Tm2, that receive apparently matched synaptic inputs from L2. Tm2 neurons also receive inputs from two retinotopically posterior neighboring columns via L4, a third type of lamina neuron. Light microscopy reveals that the connections in these L2/L4/Tm2 circuits are highly determinate. Single-cell transcript profiling suggests that nicotinic acetylcholine receptors mediate transmission within the L2/L4/Tm2 circuits, whereas L1 is apparently glutamatergic. We propose that Tm2 integrates sign-conserving inputs from neighboring columns to mediate the detection of front-to-back motion generated during forward motion
The effect of flow resistance on water saturation profile for transient two-phase flow in fractal porous media
Due to the rapid development of Micro-Electro-Mechanical System, more and more attention has been paid to the fluid properties of porous media, which is significant for petroleum engineering. However, most of surfaces of pores and capillaries in porous media are rough. On the approximation that porous medium consists of a bundle of tortuous and rough capillaries, a Buckley-Leverett conceptual model with considering flow resistance is developed based on the fractal geometry theory, which is beneficial to predict water saturation profile in porous medium. The proposed Buckley-Leverett solution is a function of fractal structural parameters (such as pore fractal dimension, tortuosity fractal dimension, maximum and minimum diameters of capillaries), fluid properties (such as viscosity, contact angle and interfacial tension) and pore structure parameter (relative roughness) in fractal porous medium. Besides, the relationship between water saturation and distance is presented according to Buckley-Leverett solution. The impaction of flow resistance on water saturation profile is discussed.Cited as: Lu, T., Li, Z., Lai, F., Meng, Y., Ma, W. The effect of flow resistance on water saturation profifile for transient two-phase flow in fractal porous media. Advances in Geo-Energy Research, 2018, 2(1): 63-71, doi: 10.26804/ager.2018.01.0
Mapping protein-specific micro-environments in live cells by fluorescence lifetime imaging of a hybrid genetic-chemical molecular rotor tag
The micro-viscosity and molecular crowding experienced by specific proteins can regulate their dynamics and function within live cells. Taking advantage of the emerging TMP-tag technology, we present the design, synthesis and application of a hybrid genetic-chemical molecular rotor probe whose fluorescence lifetime can report protein-specific micro-environments in live cells
Earnings management and corporate efficiency pre-and post-IFRS: Evidence from Taiwanese listed electronics corporations.
Associations of meat, fish and seafood consumption with kidney function in middle-aged to older Chinese: a cross-sectional study based on the Guangzhou Biobank Cohort Study
New prognostic system specific for epidermal growth factor receptor-mutated lung cancer brain metastasis
IntroductionBrain metastases (BM) from lung cancer are heterogeneous, and accurate prognosis is required for effective treatment strategies. This study aimed to identify prognostic factors and develop a prognostic system exclusively for epidermal growth factor receptor (EGFR)-mutated lung cancer BM.MethodsIn total, 173 patients with EGFR-mutated lung cancer from two hospitals who developed BM and received tyrosine kinase inhibitor (TKI) and brain radiation therapy (RT) were included. Univariate and multivariate analyses were performed to identify significant EGFR-mutated BM prognostic factors to construct a new EGFR recursive partitioning analysis (RPA) prognostic index. The predictive discrimination of five prognostic scoring systems including RPA, diagnosis-specific prognostic factors indexes (DS-GPA), basic score for brain metastases (BS-BM), lung cancer using molecular markers (lung-mol GPA) and EGFR-RPA were analyzed using log-rank test, concordance index (C-index), and receiver operating characteristic curve (ROC). The potential predictive factors in the multivariable analysis to construct a prognostic index included Karnofsky performance status, BM at initial lung cancer diagnosis, BM progression after TKI, EGFR mutation type, uncontrolled primary tumors, and number of BM.Results and discussionIn the log-rank test, indices of RPA, DS-GPA, lung-mol GPA, BS-BM, and EGFR-RPA were all significant predictors of overall survival (OS) (p ≤ 0.05). The C-indices of each prognostic score were 0.603, 0.569, 0.613, 0.595, and 0.671, respectively; The area under the curve (AUC) values predicting 1-year OS were 0.565 (p=0.215), 0.572 (p=0.174), 0.641 (p=0.007), 0.585 (p=0.106), and 0.781 (p=0.000), respectively. Furthermore, EGFR-RPA performed better in terms of calibration than other prognostic indices.BM progression after TKI and EGFR mutation type were specific prognostic factors for EGFR-mutated lung cancer BM. EGFR-RPA was more precise than other models, and useful for personal treatment
Bcp1 is the nuclear chaperone of Rpl23 in Saccharomyces cerevisiae
Eukaryotic ribosomes are composed of rRNAs and ribosomal proteins. Ribosomal proteins are translated in the cytoplasm and imported into the nucleus for assembly with the rRNAs. It has been shown that chaperones or karyopherins responsible for import can maintain the stability of ribosomal proteins by neutralizing unfavorable positive charges and thus facilitate their transports. Among 79 ribosomal proteins in yeast, only a few are identified with specific chaperones. Besides the classic role in maintaining protein stability, chaperones have additional roles in transport, chaperoning the assembly site, and dissociation of ribosomal proteins from karyopherins. Bcp1 has been shown to be necessary for the export of Mss4, a phosphatidylinositol 4-phosphate 5-kinase, and required for ribosome biogenesis. However, its specific function in ribosome biogenesis has not been described. Here, we show that Bcp1 dissociates Rpl23 from the karyopherins and associates with Rpl23 afterward. Loss of Bcp1 causes instability of Rpl23 and deficiency of 60S subunits. In summary, Bcp1 is a novel 60S biogenesis factor via chaperoning Rpl23 in the nucleus
Effects of Planting Density on Starch Particle Size Distribution and Pasting Properties of Maize Kernels along Huaihe River
The effects of different planting densities on the particle size distribution and pasting properties of starch granules in maize grains along the Huaihe River were analyzed. Taking 13 maize hybrids such as Yudan 132 and Jingke 968 as materials, three planting densities of 56 250 plants/hm2, 67 500 plants/hm2 and 77 250 plants/hm2 were set up. The effects of different planting densities on grain quality, starch particle size distribution and gelatinization characteristics of maize in the region along the Huaihe River were analyzed. The results indicated that the protein and fat content of maize grain decreased with the increase of planting density in the range of 56 250 ~ 77 250 plants/hm2. The starch content showed an increasing trend, which means, the starch/protein ratio increased. The volume and surface area percentage of large starch granules in maize grains increased significantly, while the small starch granules decreased significantly. At the same time, it was found that the peak viscosity, trough viscosity, final viscosity and breakdown value of corn starch increased significantly after rising planting density. Relevant analysis showed that the viscosity parameters such as peak viscosity of corn kernels were positively correlated with the volume percentage of small and large starch granules. There was a significant or extremely significant negative correlation with the volume percentage of medium starch granules. It shows that planting density affects the starch particle size distribution starch viscosity parameters and chemical components of corn kernels
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