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Grafting is a green, environmentally friendly, and sustainable way to prevent soil-borne diseases. Although artificial grafting is the main grafting approach used for grafting production, it has some problems which are low productivity, unstable operating quality and labor-intensive. Hence, some countries have been engaged in the development of grafting robots for the past two decades; however, the productivity of these grafting robots has no advantage when compared to artificial grafting. This study aims to develop a high-productivity grafting robot (HPR) for Solanaceae. To improve grafting productivity, this paper adopted plug trays to feed crown-removed rootstocks automatically and carried out multi-plant simultaneous grafting to improve grafting productivity and extensibility. Manipulators were employed to take out rootstocks, increase the distance between them, and transfer them to transfer cups for the simultaneous multi-plant grafting. At the same time, negative pressure mechanisms were designed for speeding up the auxiliary feeding of root-removed scions. Although the HPR was designed in a two-operator mode, a one-operator mode can also be implemented by adjusting the control program. Tests were conducted by varying the artificial feeding speed to analyze the performance of the grafting robot. The results showed that the productivity of the robot in the two-operator mode was 2250 plants/h, and 1542 plants/h in one-operator mode; comparing the artificial feeding productivity with auto grafting productivity, it was found that the capacity of the grafting robot was higher than the feeding speed of the one-operator mode but lower than that of the two-operator mode. [ABSTRACT FROM AUTHOR]

In the framework of elastocaloric (eC) refrigeration, the fatigue effect on the eC effect of natural rubber (NR) is investigated. Repetitive deformation cycles at engineering strain regime from 1 to 6 results in a rapid rupture (approx. 800 cycles). Degradation of properties and fatigue life are then investigated at three different strain regimes with the same strain amplitude: before onset strain of strain-induced crystallization (SIC) (strain regime of 0-3), onset strain of melting (strain regime of 2-5) and high strain of SIC (strain regime of 4-7). Strain of 0-3 leads to a low eC effect and cracking after 2000 cycles. Strain of 2-5 and 4-7 results in an excellent crack growth resistance and much higher eC effect with adiabatic temperature changes of 3.5K and 4.2 K, respectively, thanks to the effect of SIC. The eC stress coefficient index γ (ratio between eC temperature change and applied stress) for strains of 2-5 and 4-7 are γ2-5 =4.4KMPa-1 and γ4-7 =1.6KMPa-1, respectively, demonstrating the advantage of the strain regime 2-5. Finally, a highcycle test up to 1.7 x 105 cycles is successfully applied to the NR sample with very little degradation of eC properties, constituting an important step towards cooling applications. [ABSTRACT FROM AUTHOR]

The directly measured temperature change ΔT upon deformation (elastocaloric effect) of natural rubber was compared with indirect method, which is deduced from the Clausius-Clapeyron factor (∂σ/∂T)ε, where σ is the stress and ε is the strain. The factor (∂σ/∂T)ε can be measured by two different methods. One is to measure the stress vs. strain behavior at different static temperatures. It is found that the ΔT deduction is underestimated or even of opposite sign compared with the directly measured one. These behaviors are different from elastocaloric effect of shape memory alloys. An interpretation based on strain-induced crystallite is proposed. The other characterization is to measure the stress vs. temperature at constant strain. It results in a prediction, which is in good quantitative agreement with the directly measured one. The stress appears then to be a non-state variable, thus questioning the ergodicity of the material. [ABSTRACT FROM AUTHOR]

In the context of solid-state-cooling, the elastocaloric effect offers a very large controlled entropy change based in low-cost polymers, especially natural rubber which is environmentally friendly. However, large elastocaloric activity requires large elongation (>5), which makes this material impractical for cooling systems due to the large change in sample's area. By performing a pre-elongation, area change is limited, and β=-∂γ/∂λ (where γ is the specific entropy and λ is the elongation) is larger. The highest β value is obtained when pre-elongation is right before (at the "eve") the onset of the strain-induced crystallization, which is also interpreted in the view of molecular conformation. Experimental results obtained on a natural rubber sample showed an adiabatic temperature change of 4.3 °C for pre-elongation of 4 with further elongation of 4 (true strain change of 69%). Furthermore, the entropy exhibits a quasi-linear dependence on elongation, and the β value is found to be 6400 J K-1 m-3. [ABSTRACT FROM AUTHOR]

Calcium induces epidermal keratinocyte differentiation, but the mechanism is not completely understood. We have previously demonstrated that calcium-induced human keratinocyte differentiation requires an intracellular calcium rise caused by phosphatidylinositol 3-kinase (PI3K)-dependent activation of phospholipase C-γ1. In this study we sought to identify the upstream signaling pathway necessary for calcium activation of PI3K and its subsequent activation of phospholipase C-γ1. We found that calcium induces the recruitment of PI3K to the E-cadherin-catenin complex at the plasma membrane of human keratinocytes. Knocking-down E-cadherin, β-catenin, or p120-catenin expression blocked calcium activation of PI3K and phospholipase C-γ1 and calcium-induced keratinocyte differentiation. However, knocking-down γ-catenin expression had no effect. Calcium-induced PI3K recruitment to E-cadherin stabilized by p120-catenin at the plasma membrane requires β-catenin but not γ-catenin. These data indicate that the recruitment of PI3K to the E-cadherin/β-catenin/p120-catenin complex via β-catenin at the plasma membrane is required for calcium-induced phospholipase C-γ1 activation and, ultimately, keratinocyte differentiation. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials exhibit many interesting properties, but most 2D materials are exfoliated from layered bulk materials, limiting the development of the 2D material group. Recently, non-layered 2D materials have aroused great attention due to their excellent catalysis performance, favored compatibility with silicon substrates and high chemical activity. With high photoconductivity, high responsivity and fast response time, non-layered selenium (Se) exhibits important applications in the field of optoelectronics. In this work, we use a simple liquid phase exfoliation method to fabricate 2D Se nanoflakes from bulk Se which possesses a unique chain structure. The thickness of 2D Se nanoflakes was measured to be in the range of 5–10 nm. As-fabricated Se nanoflakes were used in a photodetector by the photoelectrochemical method, showing a high photocurrent density (1.28 μA cm−2) and photoresponsivity (10.45 μA W−1). In addition, the long-term photoelectric measurements indicate that the 2D Se-based photodetector has good time and cycle stability. Our results show that 2D Se has promising potential in liquid-based photo-detectors. [ABSTRACT FROM AUTHOR]

The vitamin D receptor (VDR) is a transcription factor that mediates a variety of biological functions of 1,25-dihydroxyvitamin D3. Although there is growing evidence of cytological and animal studies supporting the suppressive role of VDR in cancers, the conclusion is still controversial in human cancers and no systematic pan-cancer analysis of VDR is available. We explored the relationships between VDR expression and prognosis, immune infiltration, tumor microenvironment, or gene set enrichment analysis (GSEA) in 33 types of human cancers based on multiple public databases and R software. Meanwhile, the expression and role of VDR were experimentally validated in papillary thyroid cancer (PTC). VDR expression decreased in 8 types and increased in 12 types of cancer compared with normal tissues. Increased expression of VDR was associated with either good or poor prognosis in 13 cancer types. VDR expression was positively correlated with the infiltration of cancer-associated fibroblasts, macrophages, or neutrophils in 20, 12, and 10 cancer types respectively and this correlation was experimentally validated in PTC. Increased VDR expression was associated with increased percentage of stromal or immune components in tumor microenvironment (TME) in 24 cancer types. VDR positively and negatively correlated genes were enriched in immune cell function and energy metabolism pathways, respectively, in the top 9 highly lethal tumors. Additionally, VDR expression was increased in PTC and inhibited cell proliferation and migration. In conclusion, VDR is a potential prognostic biomarker and positively correlated with immune infiltration as well as stromal or immune components in TME in multiple human cancers. [ABSTRACT FROM AUTHOR]

In order to achieve continuous and dynamic detection of sugarcane nodes, improve the automatic production efficiency of pre-cut sugarcane seed, and lower the cost of mechanized sugarcane production, a detection method based on linear array charge-coupled device (CCD) photoelectric sensor signal processing was developed. Firstly, the mechanical drive unit was controlled to drive the photoelectric detection system to acquire the signal of the vertical projection of the sugarcane profile. The projection information was then binarized into profile information using the Otsu algorithm. The profile signal was then decomposed using a variable mode decomposition algorithm optimized based on the sparrow search algorithm, and the component reflecting the node content was regarded as the feature signal. Finally, the position of the wave peaks above the judgment threshold in the normalized feature signal was considered the position of the sugarcane nodes. One-way and two-way experiments were conducted to investigate the effects of scan speed and illuminance on identification precision. The results showed that the identification rate, average response time, and average error values were 98.40%, 0.13 s, and 1.36 mm at a scan speed of 75 mm/s and an illuminance of 91.91 lx. Compared to other node identification methods discussed in this article, the proposed method has a high identification rate and accuracy with a high response speed, which can improve the automation efficiency of sugarcane seed production. [ABSTRACT FROM AUTHOR]

Near-infrared (NIR)-light-triggered photothermal therapy (PTT) is a promising treatment for breast cancer. However, its therapeutic efficiency is often compromised due to the heatinduced up-regulation of heat shock proteins, which confer photothermal resistance. To solve this urgent problem, PEGylated two-dimensional boron nanosheets (B-PEG)--which allow both multimodal imaging and photothermal conversion--were loaded with gambogic acid (GA), which can inhibit heat shock protein 90 (Hsp90). Experimental findings indicated that this combination of B-PEG and GA could serve as an integrated drug delivery system for cancer diagnosis and treatment. It could be used to administer mild PTT as well as chemotherapy for breast cancer, provide improved anti-tumor effects, and reduce the toxicity of PTT, all while inhibiting breast cancer growth. This drug delivery system could offer a novel tool for administering chemotherapy combined with PTT while avoiding the adverse effects of traditional PTT. [ABSTRACT FROM AUTHOR]

Differentiated thyroid carcinoma (DTC) is the most common endocrine malignancy and highly expresses the receptor for 1,25-dihydroxyvitamin D (1,25(OH)2D). However, it is unclear whether 1,25(OH)2D regulates DTC proliferation and differentiation. Here, we found that 1,25(OH)2D3 inhibited proliferation but not differentiation of the DTC cells. Notably, CYP27B1 was elevated in DTC cells and 25-hydroxyvitamin D3 (25(OH)D3) reduced DTC cell proliferation. Knockdown of VDR did not affect the anti-proliferative effects of 1,25(OH)2D3. However, knockdown of CCAAT enhancer-binding protein β (C/EBPβ) abolished 1,25(OH)2D3-suppressed DTC cell proliferation. In addition, 1,25(OH)2D3 induced phosphorylation and translocation of C/EBPβ to the nucleus from the cytoplasm. However, inhibition of p38 mitogen-activated protein kinases (MAPK) abrogated 1,25(OH)2D3- induced phosphorylation and nuclear translocation of C/EBPβ as well as 1,25(OH)2D3- suppressed DTC cell proliferation. Knockdown of C/EBPβ reduced the expression of Notch3. Knockdown of Notch3 blocked 1,25(OH)2D3-suppressed DTC cell proliferation. In the DTC cell-derived xenograft SCID mouse, knockdown of C/EBPβ markedly increased tumor growth and proliferation and decreased apoptosis. In DTC patients, C/EBPβ was predominantly located in the cytoplasm of DTC cells in the tumor tissue when compared with adjacent non-cancerous tissue in which C/EBPβ is located in the nucleus. In conclusion, C/EBPβ stimulated Notch3 signaling via the p38 MAPK-dependent pathway mediates the inhibitory effect of 1,25(OH)2D on DTC cell proliferation. [ABSTRACT FROM AUTHOR]

Thyroid cancer has the fastest rising incidence among cancers, especially for differentiated thyroid carcinoma (DTC). Although the prognosis of DTC is relatively good, if it changes to anaplastic thyroid carcinoma (ATC), the prognosis will be very poor. The prognosis of DTC is largely depending on the degree of cell differentiation and proliferation. However, whether the vitamin D receptor (VDR) plays a role in regulating the proliferation and the differentiation of DTC cells is unclear. In the present study, we found that VDR was upregulated in DTC tissues compared to the a djacent non-cancerous tissue. Knockdown of VDR increased proliferation and decreased differentiation proliferation in DTC cells in vitro as well as DTC cell-derived xenografts in vivo. In contrast, overexpression of VDR had an opposite effect. Knockdown of E-cadherin abolished VDR-induced suppression of proliferation and enhancement of differentiation of the DTC cells. Knockdown of β-catenin partially reversed the effect of the VDR knockdown. VDR increases the levels of E-cadherin in the plasma membrane a nd decreases the levels of β-catenin in the nucleus. VDR binds to E-cadherin and β-catenin in the plasma membrane of the DTC cell. Taken together, VDR inhibits DTC cell proliferation and promotes differentiation via regulation of the E-cadherin/β-catenin complex, potentially representing novel clues for a therapeutic strategy to attenuate thyroid cancer progression. [ABSTRACT FROM AUTHOR]

Extracellular Ca2+ (Ca2+o) is a critical regulator that promotes differentiation in epidermal keratinocytes. The calcium sensing receptor (CaR) is essential for mediating Ca2+ signaling during Ca2+o-induced differentiation. Inactivation of the endogenous CaR-encoding gene CASR by adenoviral expression of a CaR antisense cDNA inhibited the Ca2+o-induced increase in intracellular free calcium (Ca2+i) and expression of terminal differentiation genes, while promoting apoptosis. Ca2+o also instigates E-cadherin-mediated cell-cell adhesion, which plays a critical role in orchestrating cellular signals mediating cell survival and differentiation. Raising Ca2+o concentration ([Ca2+]o) from 0.03 to 2 mM rapidly induced the co-localization of α-, β-, and p120-catenin with E-cadherin in the intercellular adherens junctions (AJs). To assess whether CaR is required for the Ca2+o-induced activation of E-cadherin signaling, we examined the impact of CaR inactivation on AJ formation. Decreased CaR expression suppressed the Ca2+o-induced AJ formation, membrane translocation, and the complex formation of E-cadherin, catenins, and the phosphatidylinositol 3-kinase (PI3K), although the expression of these proteins was not affected. The assembly of the E-cadherin-catenin-PI3K complex was sensitive to the pharmacologic inhibition of Src family tyrosine kinases but was not affected by inhibition of Ca2+o-induced rise in Ca2+i. Inhibition of CaR expression blocked the Ca2+o-induced tyrosine phosphorylation of β-, γ-, and p120-catenin, PI3K, and the tyrosine kinase Fyn and the association of Fyn with E-cadherin and PI3K. Our results indicate that the CaR regulates cell survival and Ca2+o-induced differentiation in keratinocytes at least in part by activating the E-cadherin/PI3K pathway through a Src family tyrosine kinase-mediated signaling. [ABSTRACT FROM AUTHOR]

The production of hydroponic leafy vegetable plug-seedlings uses coco-peat as culture substrate in South China. Coco-peat has lowered density than peat-moss, and the friction between substrate block and pickup tool is small. So, it is hard to pick up in mechanism transplantation. In order to increase the friction, the existing transplanting manipulator had relatively complex structures. To simplify the structure of transplanting manipulator and improve the stability of picking up substrate block, four stainless steel fingers with rectangular cross-section were used in this research. A vertical driving was used to realize the coupling effect that could insert and shrink at the same time, by applying different combination of constraints to the steel fingers. This could increase friction between the steel fingers and the substrate block, and then enhance the stability of the substrate block. Different combinations of constraints were applied to the rectangular stainless steel fingers (3 mm x 0.8 mm). The working videos of steel fingers were taken by high-speed photography. High-speed motioned analysis software was used to acquire and analyze traces of steel fingers movements. When the length which top end of the steel fingers moved outward (M) is equal to 1.5 mm, the length which guiding part widened (N) is equal to 1 mm, the shrinking distance of steel fingers is 4.2 mm. In this research, 16-day hydroponic leafy vegetable plug-seedlings were used for performance, which cultivated with coco-peat substrate with the moisture in the substrate at 81%. The transplanting manipulator was attached to a Denso robotic arm to conduct transplanting performance test. When the shrinking distance of steel fingers increased from 0 mm to 3.2 mm and the inserting angle decreased from 80° to 77°, the lifting force of substrate block increased by 118% from 1.45 N to 3.16 N. However, excessive shrinkage stirred the substrate block, which would reduce the friction between the substrate block and pickup parts and lowered the lifting force of pickup part in the substrate block. The experimental results also demonstrated that when the shrinking distance of the steel fingers reached 3.2 mm and the root distribution rate reached 46%, the success rate of transplantation was 80%. When the leafy vegetable plug-seedlings root distribution rate reached 92%, the success rate of transplantation was 96.67%. The degree of root distribution rate was positively correlated with the transplantation success rate. Therefore, in order to ensure an acceptable success rate of transplantation, the root distribution rate of leafy vegetable plug-seedlings should be at least 90%. This study provides a technical reference for developing simplified transplanting manipulator that can be used to transplant the hydroponic leafy vegetable plug-seedlings with coco-peat as the culture substrate. [ABSTRACT FROM AUTHOR]

Humans with selected mutations in the vitamin D receptor (VDR) and mouse models lacking VDR develop alopecia. Mice null for the Vdr gene are born with a normal coat of hair, but fail to initiate normal hair follicle cycling. In this study, we examined the morphology of the hair follicle of the Vdr null mouse during days 13–22 when the hair follicle normally initiates and completes the first catagen. We then explored the possibility that the abnormality in hair follicle cycling was associated with abnormal expression of hairless (Hr), a putative transcriptional regulator known to regulate hair follicle cycling and recently shown to regulate VDR transcriptional activity. Our results demonstrate the progressive deterioration of the hair follicle through catagen. Comparable to VDR, Hr was found in the basal cells of the epidermis and ORS of the hair follicle. However, Hr was also found in the IRS and matrix of the follicle, regions with little or no VDR. Hr levels increased during catagen, reaching a peak by day 19. Levels of Hr were greater in the Vdr null mice compared to wildtype controls, results confirmed by quantitative RT-PCR. We conclude that lack of VDR causes disruption of hair follicle structure during the first catagen resulting in failure of subsequent hair follicle cycling. These changes are associated with increased expression of Hr, suggesting a role for VDR in regulating Hr expression. Both Hr and VDR are required for normal hair follicle cycling. J. Cell. Physiol. 207: 340–353, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]