An integrated method for compensating and correcting nonlinear error in five-axis machining utilizing cutter contacting point data.

In current five-axis computer numerical control (CNC) machining, the use of minute linear path segments as an approximation for the ideal cutter contacting (CC) point trajectory is still prevalent. However, introducing rotation axes leads to a deviation of the actual CC point trajectory from the ideal, resulting in nonlinear errors. An integrated method is proposed in this paper for compensating and correcting both the contour error, associated with the approximation of the part surface by the ideal CC point trajectory and the nonlinear error of the CC point trajectory based on the information in the CC point data. By analyzing the spatial relationship between the tool posture and the CC point path during the five-axis linear interpolation process, two adjacent machining tool positions containing CC point data information are selected as the starting and ending points of the five-axis linear interpolation machining. The ideal tool center point and the actual CC point are calculated during the interpolation process, as well as the distance and the unit vector in the perpendicular direction between the actual CC point and the ideal CC point trajectory segment. In the comprehensive error compensation and correction phase, the obtained unit vectors are used as direction vectors for error compensation, and the tool center point during interpolation is first compensated and corrected. This ensures the actual CC point and the contour curve are on the same plane. The compensation direction for contour error is calculated using the start/end tool axis vectors and the ideal CC point trajectory vectors. The size of the contour error approximating the contour curve is calculated through the chord error. A second compensation and correction are applied to the tool center point for interpolation, ultimately achieving comprehensive compensation and correction of nonlinear errors. The data calculations were conducted in the MATLAB environment using actual machining data. After compensation and correction, the contour error was reduced by 76%, the nonlinear error of the CC point trajectory decreased to below 0.88 µm, and the comprehensive nonlinear error of the CC point trajectory was reduced from 19 to 1.5 µm, a reduction of 93%. This demonstrates significant practical value in enhancing the accuracy of five-axis CNC machining. Through actual machining verification, after using the method described in this paper, the average surface roughness decreased from 1.133 to 0.220 µm, and the maximum surface roughness decreased from 6.667 to 1.240 µm. This significantly demonstrates that the compensation and correction method proposed in this paper can significantly improve the surface quality of machined parts.

Control over Charge Separation by Imine Structural Isomerization in Covalent Organic Frameworks with Implications on CO2 Photoreduction.

Two-dimensional covalent organic frameworks (COFs) are an emerging class of photocatalytic materials for solar energy conversion. In this work, we report a pair of structurally isomeric COFs with reversed imine bond directions, which leads to drastic differences in their physical properties, photophysical behaviors, and photocatalytic CO2 reduction performance after incorporating a Re(bpy)(CO)3Cl molecular catalyst through bipyridyl units on the COF backbone (Re-COF). Using the combination of ultrafast spectroscopy and theory, we attributed these differences to the polarized nature of the imine bond that imparts a preferential direction to intramolecular charge transfer (ICT) upon photoexcitation, where the bipyridyl unit acts as an electron acceptor in the forward imine case (f-COF) and as an electron donor in the reverse imine case (r-COF). These interactions ultimately lead the Re-f-COF isomer to function as an efficient CO2 reduction photocatalyst, while the Re-r-COF isomer shows minimal photocatalytic activity. These findings not only reveal the essential role linker chemistry plays in COF photophysical and photocatalytic properties but also offer a unique opportunity to design photosensitizers that can selectively direct charges.

Circ-SATB2 (hsa_circ_0008928) and miR-150-5p are regulators of TRIM66 in the regulation of NSCLC cell growth and metastasis of NSCLC cells via the ceRNA pathway.

Circular RNA (circRNA) was an important modulator and potential molecular target of nonsmall cell lung cancer (NSCLC). CircSATB2 was reported to be upregulated in NSCLC. However, the role and mechanism of circSATB2 in NSCLC progression remain to be illustrated. The RNA and protein expression was detected by quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry assay. Cell counting kit-8, cell colony formation, and 5-ethynyl-2'-deoxyuridine assays were applied to assess cell growth. The migrated and invaded cells were examined by transwell assay. Flow cytometry was performed to measure apoptotic cells. The interaction among circSATB2, microRNA-150-5p (miR-150-5p), and tripartite motif-containing protein 66 (TRIM66) was identified by dual-luciferase reporter assay and RNA immunoprecipitation assay. An in vivo experiment was conducted to investigate the effect of circSATB2 on tumor growth. CircSATB2 expression was highly expressed in NSCLC tissues and cell lines. CircSATB2 and TRIM66 silencing both suppressed NSCLC cell growth, migration, and invasion whereas promoted NSCLC cell apoptosis. CircSATB2 acted as a molecular sponge for miR-150-5p, and miR-150-5p interacted with the 3' untranslated region (3'UTR) of TRIM66. Moreover, circSATB2 knockdown-induced effects were partly reversed by TRIM66 overexpression in NSCLC cells. Besides, cirSATB2 expression was negatively correlated with miR-150-5p level and positively correlated with TRIM66 level in NSCLC tumor tissues. CircSATB2 knockdown blocked xenograft tumor growth in vivo. In summary, this study verified that circSATB2 stimulated NSCLC cell malignant behaviors by miR-150-5p/TRIM66 pathway, providing a possible circRNA-targeted therapy for NSCLC.

Tetranuclear CuII Cluster as the Ten Node Building Unit for the Construction of a Metal-Organic Framework for Efficient C2 H2 /CO2 Separation.

Rational design of high nuclear copper cluster-based metal-organic frameworks has not been established yet. Herein, we report a novel MOF (FJU-112) with the ten-connected tetranuclear copper cluster [Cu4 (PO3 )2 (µ2 -H2 O)2 (CO2 )4 ] as the node which was capped by the deprotonated organic ligand of H4 L (3,5-Dicarboxyphenylphosphonic acid). With BPE (1,2-Bis(4-pyridyl)ethane) as the pore partitioner, the pore spaces in the structure of FJU-112 were divided into several smaller cages and smaller windows for efficient gas adsorption and separation. FJU-112 exhibits a high separation performance for the C2 H2 /CO2 separation, which were established by the temperature-dependent sorption isotherms and further confirmed by the lab-scale dynamic breakthrough experiments. The grand canonical Monte Carlo simulations (GCMC) studies show that its high C2 H2 /CO2 separation performance is contributed to the strong π-complexation interactions between the C2 H2 molecules and framework pore surfaces, leading to its more C2 H2 uptakes over CO2 molecules.

Optimized Sieving Effect for Ethanol/Water Separation by Ultramicroporous MOFs.

High-purity ethanol is a promising renewable energy resource, however separating ethanol from trace amount of water is extremely challenging. Herein, two ultramicroporous MOFs (UTSA-280 and Co-squarate) were used as adsorbents. A prominent water adsorption and a negligible ethanol adsorption identify perfect sieving effect on both MOFs. Co-squarate exhibits a surprising water adsorption capacity at low pressure that surpassing the reported MOFs. Single crystal X-ray diffraction and theoretical calculations reveal that such prominent performance of Co-squarate derives from the optimized sieving effect through pore structure adjustment. Co-squarate with larger rhombohedral channel is suitable for zigzag water location, resulting in reinforced guest-guest and guest-framework interactions. Ultrapure ethanol (99.9 %) can be obtained directly by ethanol/water mixed vapor breaking through the columns packed with Co-squarate, contributing to a potential for fuel-grade ethanol purification.

A Flexible Hydrogen-Bonded Organic Framework Constructed from a Tetrabenzaldehyde with a Carbazole N-H Binding Site for the Highly Selective Recognition and Separation of Acetone.

Rational design of hydrogen-bonded organic frameworks (HOFs) with multiple functionalities is highly sought after but challenging. Herein, we report a multifunctional HOF (HOF-FJU-2) built from 4,4',4'',4'''-(9H-carbazole-1,3,6,8-tetrayl)tetrabenzaldehyde molecule with tetrabenzaldeyde for their H bonding interactions and carbazole N-H site for its specific recognition of small molecules. The Lewis acid N-H sites allow HOF-FJU-2 facilely separate acetone from its mixture with another solvent like methanol with smaller pKa value. The donor (D)-π-acceptor (A) aromatic nature of the organic building molecule endows this HOF with solvent dependent luminescent/chromic properties, so the column acetone/methanol separation on HOF-FJU-2 can be readily visualized.

Nesfatin-1 alleviated lipopolysaccharide-induced acute lung injury through regulating inflammatory response associated with macrophages modulation.

Acute lung injury (ALI) is a continuum of lung changes associated with uncontrolled excessive lung inflammation. However, the pathogenesis of ALI is still complicated and effective clinical pharmacological management is required. Various signaling pathways are involved in the inflammatory responses of ALI. Here, we aimed to explore the role of nesfatin-1, an amino-acid peptide with anti-inflammatory action, in an LPS-induced ALI mice model, and its role in regulating macrophages in response to LPS stimulation in vitro. This was to clarify the underlying mechanisms of regulating the inflammatory response in the development of ALI. The results show that nesfatin-1 expression was downregulated in the lung tissues of ALI mice compared to control mice. Nesfatin-1 treatment ameliorated the inflammatory response and lung tissue damage in LPS-induced ALI in mice. In vitro studies showed that nesfatin-1 attenuated the generation and release of proinflammatory cytokines interleukin-6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α) in LPS-induced RAW 264.7 cells. Nesfatin-1 also inhibited reactive oxygen species production and improved superoxide dismutase (SOD) activity in LPS-induced RAW 264.7 cells. These findings suggest that nesfatin-1 exerted a crucial role in regulating the LPS-mediated activation of M1 macrophages. Further mechanism investigations indicated that nesfatin-1 inhibited the activation of p38 MAPK/c-Jun and NF-κB pathways in LPS-induced RAW 264.7 cells, as evidenced by decreased expression levels of p-p38, p-c-Fos, and p-p65. Overall, nesfatin-1 alleviated LPS-induced ALI, which might be attributed to regulating inflammatory response through macrophages modulation.

STIM2 promotes the invasion and metastasis of breast cancer cells through the NFAT1/TGF-ß1 pathway.

A large amount of evidence indicates that the abnormal activation of multiple signal transduction pathways in cells is closely related to the occurrence and development of tumors. TGF-ß and NFAT1 signaling pathways can inhibit cell proliferation and promote apoptosis in the early stage of breast cancer, but with the increase of tumor malignancy, the two appear to promote tumor progression and deterioration. Therefore, the study of the relationship between STIM2 and NFAT1/TGF-ß1 is helpful for the discovery and treatment of breast cancer, which is of great significance for improving the survival rate of breast cancer patients. This article focuses on the effect of STIM2 molecules on breast cancer cell migration through the NFAT1/ TGF-ß1 pathway and discusses the regulatory mechanism of STIM2 affecting breast cancer cell migration. Experimental data shows that the positive rate of breast cancer NFAT1 is 54%, which is significantly lower than that of benign breast Tissue 85%; the positive expression rate of TGF-ß1 in benign breast tissue is 85%, and the positive expression rate in breast cancer tissue is 49%. The results show that STIM2 protein can promote the invasion and metastasis of breast cancer cells through the NFAT1 / TGF-ß1 pathway.

An Ultramicroporous Hydrogen-Bonded Organic Framework Exhibiting High C2 H2 /CO2 Separation.

The separation of C2 H2 /CO2 is not only industrially important for acetylene purification but also great scientific challenge due to their very similar molecular size and physical properties. To address this difficulty, herein, we present an ultramicroporous hydrogen-bonded organic framework (HOF-FJU-1) from tetracyano bicarbazole to separate C2 H2 from CO2 by taking advantage of differences in their electrostatic potential distribution. This material possesses a suitable pore environment and electrostatic potential distribution fitting well to C2 H2 , thus showing extra strong affinity to C2 H2 (46.73 kJ mol-1 ) and the highest IAST selectivity of 6675 for C2 H2 /CO2 separation among the adsorbents reported. The single crystal X-ray diffraction reveals that the suitable pore environment in HOF-FJU-1 provides multiple C-H⋅⋅⋅π and hydrogen-bonded interactions N⋅⋅⋅H-C with C2 H2 molecules. Dynamic breakthrough experiments demonstrate its outstanding separation performance to C2 H2 /CO2 mixtures.

The effect of miR-138 on the proliferation and apoptosis of breast cancer cells through the NF-κB/VEGF signaling pathway.

The analyze the effect of miR-138 on the proliferation and apoptosis of breast cancer cells through the NF-κB/VEGF signaling pathway is the Objective of this experiment. For this aim, the endometrial stem breast cancer cell line MCF-7 was cultured in vitro, and the overexpression mimic miR-138 mimics and the inhibitor anti-miR-138 were transfected into the endometrial stem breast cancer cell line MCF-7, which was set to overexpress miR-138 group and interfere with miR-138, and set up negative control of overexpression and negative control of inhibitor. Observe the cell proliferation and apoptosis ability of each group, and the changes in tumor necrosis factor-α (TNF-α), interleukin 1ß, 6, 18 (IL-1ß, IL-6, IL-18) levels, and compare the Bax of each group, NF-κB, VEGF protein expression level. Results showed that the proliferation ability of the miR-138 overexpression group was significantly lower than that of the miR-138 overexpression control group (P<0.05); the proliferation ability of the miR-138 interference group was significantly higher than that of the miR-138 interference control group (P<0.05). The apoptosis rate, caspase-3 and caspase-9 expression levels of the miR-138 overexpression group were significantly higher than those of the miR-138 overexpression control group (P<0.05);  the apoptosis rate, caspase-3 and caspase-9 expression levels of the miR-138 interference group were significantly lower than those of the miR-138 interference control group (P<0.05). The expression levels of IL-1 ß, IL-6, IL-18 and TNF - α in the miR-138 overexpression group were significantly lower than those in the miR-138 overexpression control group (P < 0.05). The protein expression levels of Bax, NF-κB and VEGF in the miR-138 overexpression group were significantly lower than those in the miR-138 overexpression control group (P < 0.05); the protein expression levels of Bax, NF-κB and VEGF in the miR-138 interference group were significantly higher than those in the miR-138 interference control group (P <0.05). The proliferation ability of the miR-138 overexpression group was significantly lower than that of the miR-138 overexpression control group (P < 0.05); the proliferation ability of the miR-138 + NF-κB overexpression group was significantly higher than that of the miR-138 overexpression group (P<0.05). The apoptosis rate of the miR-138 + NF-κB overexpression group was significantly lower than that of the miR-138 overexpression group (P < 0.05). Then MiR-138 can significantly inhibit the proliferation of breast cancer cells, promote apoptosis, and regulate the expression of inflammatory factors in the cells. It is speculated that the related mechanism may be related to the negative regulation of the NF-κB/VEGF signaling pathway.

Efficient Separation of Acetylene-Containing Mixtures Using ZIF-8 Membranes.

Metal-organic framework (MOF) membranes show great potential in the separation of acetylene mixtures. In this work, we have prepared ZIF-8 membranes on polyamide (PA) substrates for the highly selective separation of acetylene/methane and acetylene/carbon dioxide mixtures. The C2H2/CH4 and C2H2/CO2 mixtures can be successfully separated using the ZIF-8 membranes, with separation factors of 12.1 and 1.8, respectively. Based on the results of the cross-permeation tests of C2H2/CH4, CO2/CH4, and C2H2/CO2, the separation mechanism of C2H2/CH4 in our ZIF-8 membrane can be attributed to a higher affinity for acetylene and molecular sieving effect, while C2H2/CO2 separation is related to thermodynamic factors. It is worth noting that this is the first example of MOF membranes to successfully separate C2H2 from CH4 and CO2.

Metal-Organic Framework with Rich Accessible Nitrogen Sites for Highly Efficient CO2 Capture and Separation.

A novel microporous metal-organic framework (FJU-44), with abundant accessible nitrogen sites on its internal surface, was constructed from the tetrapodal tetrazole ligand tetrakis(4-tetrazolylphenyl)ethylene (H4TTPE) and copper chloride. Notably, the CO2 uptake capacity (83.4 cm3/g, at 273 K and 1 bar) in the activated FJU-44a is higher than most of tetrazolate-containing MOF materials. Particularly, FJU-44a exhibits superior adsorption selectivity of CO2/N2 (278-128) and CO2/CH4 (44-16), which is comparable to some well-known CO2 capture materials. Furthermore, the fixed-bed breakthrough experiment indicates that the postcombustion flue gas flow over a packed column with FJU-44a adsorbents can be effectively separated.

Robustness, Selective Gas Separation, and Nitrobenzene Sensing on Two Isomers of Cadmium Metal-Organic Frameworks Containing Various Metal-O-Metal Chains.

Poor stability has been one of the major difficulties affecting to the practical application of metal-organic frameworks (MOFs). In this work, we obtained two 3D structurally isomeric Cd-MOFs, {[Cd6(NH2Me2)2(PTB)4(HCOO)2(H2O)]·(DMF)13·(H2O)4} n (FJU-35) and {[Cd6(NH2Me2)2(PTB)4(HCOO)2]·(DMF)6·(H2O)2} n (FJU-36) (H3PTB = pyridine-2,4,6-tribenzoic acid) containing different CdII-O-CdII chains by varying the addition agents. FJU-35 with coordinated solvent and formate in asymmetric µ3-η1:η2 coordination mode within the CdII-O-CdII chains is vulnerable to external attacks and is apt to collapse after activation, while FJU-36 with no coordinated solvent in the CdII-O-CdII chains but fully protected by the carboxylates from the ligands and the symmetric formate in the coordination mode µ3-η2:η2 is stable, and its activated sample shows efficient separation of C2H2/CH4 and C2H2/CO2 mixtures. Conversely, FJU-35 with more vulnerability is more sensitive to the detection of nitrobenzene than FJU-36.

Additive-Induced Supramolecular Isomerism and Enhancement of Robustness in Co(II)-Based MOFs for Efficiently Trapping Acetylene from Acetylene-Containing Mixtures.

Although supramolecular isomerism in metal-organic frameworks (MOFs) would offer a favorable platform for in-depth exploring their structure-property relationship, the design and synthesis of the isomers are still rather a challenging aspect of crystal engineering. Here, a pair of supramolecular isomers of Co(II)-based MOFs (FJU-88 and FJU-89) can be directionally fabricated by rational tuning the additives. In spite of the fact that the isomers have the similar Co3 secondary building units and organic linkers, they adopt distinct networks with acs and snw topologies, respectively, which derive from the conformational flexibility of the organic ligands. It is noteworthy that the porous structure of FJU-88 would be collapsed after removal of the solvent from the pores. But FJU-89a shows permanent porosity accompanied with unusual hierarchical micro- and mesopores and superior gas selective adsorption performance. In addition, FJU-89a can efficiently trap C2H2 from C2H2/CO2 and C2H2/CH4 mixture gases through fixed-bed dynamic breakthrough experiments.