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Graphical abstract Highlights • Compounds from the rhizosphere soil of Lanzhou lily were isolated and identified. • Phytotoxic activities of the compounds were evaluated and primary allelochemicals were clarified. • Concentrations of allelochemicals in the rhizosphere soil were quantified. Abstract Lanzhou lily (Lilium davidii var. unicolor) is a perennial plant with medical and edible dual purpose in China and mainly planted in the middle area of Gansu province as a bulb crop. Like many other plants of the genus Lilium , the yield and quality of Lanzhou lily have been severely hampered by replanting failure during the cultivation. Previous reports showed that aqueous extractions of different organs from Lilium plants influenced the seed germination and seedling growth of several target plants. But the specific compounds which are responsible for the phytotoxicity remain obscure. In this study, six compounds were isolated and elucidated from the rhizosphere soil of Lanzhou lily. Among them, dibutyl phthalate, decyl trans - p -coumarate, 7-oxo-sitosterol, 6-hydroxystigmast-4-en-3-one and β-sitosterol-3- O -glucoside, observably inhibited the growth of Lactuca sativa and Lanzhou lily seedlings, were clarified as main allelochemicals. They were further confirmed and quantified in the rhizosphere by high-performance liquid chromatography (HPLC), with a total concentration of 117.36 μg/g (dry soil). These findings provide allelopathic evidence of Lanzhou lily, which may be helpful for clarifying the replanting problems of Lilium plants. [ABSTRACT FROM AUTHOR]

Abstract Nuclear receptor RXRα plays an important role in many biological and pathological processes. The nongenomic action of RXRα is implicated in many cancers. K-8008, a non-canonical RXRα ligand derived from sulindac, inhibits the TNFα-activated PI3K/AKT pathway by mediating the interaction between a truncated form of RXRα (tRXRα) and the p85α regulatory subunit of PI3K and exerts potent anticancer activity in animal model. Herein we report our studies of a novel series of K-8008 analogs as potential anticancer agents targeting RXRα. Two compounds 8b and 18a were identified to have slightly stronger binding to RXRα and improved apoptotic activities in breast cancer cells. Graphical abstract Image 1 Highlights • Four series of sulindac analogs (26 compounds) were designed and synthesized. • 8b and 18a have improved binding affinity and apoptotic activity against breast cancer cells. • 8b and 18a can induce the PARP cleavage in a RXRα-dependent manner. [ABSTRACT FROM AUTHOR]

Abstract Aphelenchoides besseyi and Ditylenchus destructor can cause serious problems for a number of important agricultural crops and vegetables. In this study, the ethanol extract of Stellera chamaejasme L. roots showed strong nematicidal activity against Aphelenchoides besseyi and Ditylenchus destructor. By using a bioactivity-driven fractionation, three biflavonoids were isolated from the extract and their structures were identified by mass and nuclear magnetic resonance spectral data. Nematicidal activity bioassays revealed that isoneochamaejasmin A had the strongest nematicidal activity against A. besseyi and D. destructor with LC 50 values of 2.32 and 0.18 mM at 72 h, respectively. Chamaejasmenin B displayed weaker nematicidal activity against A. besseyi with an LC 50 value of 3.94 mM at 72 h. Neochamaejasmin B induced the lowest mortality against D. destructor with an LC 50 values of 15.6 mM at 72 h. These results suggested that the kind and position of substitutions and the relative configuration of 2-H/3-H and 2"-H/3"-H could be considered as important factors responsible for the nematicidal activity of these purified C-3/C-3″ biflavonoids. Graphical abstract Unlabelled Image Highlights • isoneochamaejasmin A was found to display the strongest activities against two phytonematodes. • The kind and position of substitutions and the relative configuration of 2-H/3-H and 2"-H/3"-H are important factors. • The extracts and the biflavonoids from S. chamaejasme roots might be of use as botanical nematicides. [ABSTRACT FROM AUTHOR]

In this paper, to improve the pose measurement accuracy of the Time-of-Flight (ToF) camera for space non-cooperative targets, a pose estimation method based on ORBFPFH Simultaneous Localization and Mapping (SLAM) with effective integration of strength and depth measurement information is proposed. The primary process of the method is as follows: First, a unique ORBFPFH Bag of Words (BoW) model for space targets is trained based on the ToF image dataset of spacecraft; Secondly, the pose of the non-cooperative space target is tracked based on the ORBFPFH feature and optimized using the pose graph; Then, based on the ORBFPFH BoW model, loop closure is detected to reduce the cumulative error. Finally, the proposed method is tested on the ToF image dataset: compared with the advanced ORB-SLAM2 algorithm, the proposed method has a minor translation error and rotation error on the test data, with a mean translation error less than 0.144 m and mean rotation error less than 0.642°. The test results show that the proposed method can improve the pose estimation accuracy of space non-cooperative targets, achieve a better 3D point cloud reconstruction effect, and provide technical support for space applications such as rendezvous and docking of non-cooperative spacecraft. © 2001 Elsevier Science. All rights reserved [ABSTRACT FROM AUTHOR]

Autotoxicity has been considered as one of the critical factors resulting in replanting failure in agriculture. To clarify the chemical reasons for the replanting problems of Pinellia ternate , a widely used and cultivated Traditional Chinese Medicine, eight compounds were isolated and identified from its rhizosphere soil. Bioassays showed that chrysophanol ( 1 ), benzofuran ( 6 ) and protocatechuic aldehyde ( 8 ) obviously inhibited the seedling growth of P. ternate and Raphanus sativus in a concentration-dependent manner. The isolated compounds were further confirmed and quantified by HPLC in the rhizosphere soil and tissues of P. ternate , and the origins of the allelochemicals being released into the soil environment were also investigated. Physiological analyses demonstrated that the allelochemicals evidently affected the levels of protective enzymes in the tested plant seedlings and caused membrane damage, which resulted in the reduction of cell vitality. These findings provide allelopathic evidence for the replanting problems of P. ternate and would be helpful for assessing plant-soil interactions. [ABSTRACT FROM AUTHOR]

Additive manufacturing (AM) has been recognized as a promising technology for achieving more secure and resilient supply chains to support social transitions to sustainable post-fossil carbon societies. AM is considered to be efficient and sustainable and its environmental impact is mainly from energy consumption. Therefore, it is of great significance to accurate predict and thus reduce the energy consumption of AM. However, current models to predict AM energy consumption are not sufficiently accurate. In this paper, a hybrid mechanism-based and data-driven approach is proposed to forecast the AM energy consumption. This approach accurately modelled the working time and power of each energy-consuming component of the FDM machine. Firstly, the physical model was used to establish the energy consumption prediction framework which documents the total energy into energy consumed by each component. Secondly, the data-driven method was leveraged via data fitting and deep learning to obtain the power and temporal model of the nozzle and the platform, considering their working states and interactions between them and the cooling fan. Thirdly, experimental measurements and G-code parsing were utilized to obtain data of the power model and the temporal model of the remaining components. In this work, the different types of parts were fabricated by the fused deposition modelling (FDM) printer and the energy consumption was measured and compared with the predicted values to verify the accuracy and effectiveness of the proposed method. Finally, the proposed method was compared with other methods to document the benefits of the proposed method. The results showed that the prediction accuracy of the proposed method for these four experiments was more than 94% accurate and it outperformed other methods. The proposed method can be used to guide process design to more accurately predict and thus reduce the energy consumption of AM parts during their manufacturing processes. [ABSTRACT FROM AUTHOR]

The high-voltage spindles (HVSs), one of the characteristic oscillations that include theta frequencies in the basal ganglia (BG)-cortical system, are involved in immobile behavior and show increasing power in Parkinson's disease (PD). Our previous results suggested that the D2 dopamine receptor might be involved in HVSs modulations in a rat model of PD. Membrane resonance is one of the cellular mechanisms of network oscillation; therefore, we investigated how dopamine modulates the theta frequency membrane resonance of neurons in the subthalamic nucleus (STN), a central pacemaker of BG, and whether such changes in STN neurons subsequently alter HVSs in the BG-cortical system. In particular, we tested whether dopamine modulates HVSs through hyperpolarization-activated cyclic nucleotide-gated (HCN) channels-dependent membrane resonance in STN neurons. We found that an antagonist of D2 receptors, but not of D1 receptors, inhibited membrane resonance and HCN currents of STN neurons through a G-protein activity in acute brain slices. Our further in vivo experiments using local injection of a D2 receptor antagonist or an HCN blocker in STNs of free-moving rats showed an increase in HVSs power and correlation in the BG-cortical system. Local injection of lamotrigine, an HCN agonist, counteracted the effect induced by the D2 antagonist. Taken together, our results revealed a potential cellular mechanism underlying HVSs activity modulation in the BG-cortical system, i.e. tuning HCN activities in STN neurons through dopamine D2 receptors. Our findings might lead to a new direction in PD treatment by providing promising new drug targets for HVSs activity modulation. [ABSTRACT FROM AUTHOR]

Allelopathy, the negative effect on plants of chemicals released to the surroundings by a neighboring plant, is an important factor which contributes to the spread of some weeds in plant communities. In this field, Stellera chamaejasme L . (Thymelaeaceae) is one of the most toxic and ecologically-threatening weeds in some of the grasslands of north and west China. Bioassay-guided fractionation of root extracts of this plant led to the isolation of eight flavonoids 1 – 8 , whose structures were elucidated by spectroscopic analysis. All compounds obtained, except 7-methoxylneochaejasmin A ( 4 ) and (+)-epiafzelechin ( 5 ), showed strong phytotoxic activity against Arabidopsis thaliana seedlings. Seedling growth was reduced by neochamaejasmin B ( 1 ), mesoneochamaejasmin A ( 2 ), chamaejasmenin C ( 3 ), genkwanol A ( 6 ), daphnodorin B ( 7 ) and dihydrodaphnodorin B ( 8 ) with IC 50 values of 6.9, 12.1, 43.2, 74.8, 7.1 and 27.3 μg/mL, respectively, and all of these compounds disrupted root development. Endogenous auxin levels at the root tips of the A. thaliana DR5::GUS transgenic line were largely reduced by compounds 1 , 2 and 6 – 8 , and were increased by compound 4 . Moreover, the inhibition rate of A. thaliana auxin transport mutants pin2 and aux1 – 7 by compounds 1 – 8 were all lower than the wild type (Col-0). The influence of these compounds on endogenous auxin distribution is thus proposed as a critical factor for the phytotoxic effect. Compounds 1 , 2 , 4 and 8 were found in soils associated with S. chamaejasme , and these flavonoids also showed phytotoxicity to Clinelymus nutans L., an associated weed of S. chamaejasme . These results indicated that some phytotoxic compounds from roots of S. chamaejasme may be involved in the potential allelopathic behavior of this widespread weed. [ABSTRACT FROM AUTHOR]

Abstract: Cadmium selenide (CdSe) nanocrystalline thin films were prepared by chemical bath deposition (CBD) using ammonia and triethanolamine (TEA) as complexing agents, cadmium chloride and sodium selenosulphate as the sources of Cd2+ and Se2− ions, respectively. The structural and optical properties of CdSe nanocrystalline thin films were investigated as a function of the sodium selenosulphate concentrations or ammonia concentrations in precursors using scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) measurements, transmission electron microscopy (TEM) and UV–visible spectrophotometer measurements. The results reveal that the CdSe thin films are in the pure cubic phase, which composed of a large number of uniform spherical particles. Each spherical particle contains many nanocrystals 3–10nm in crystallite size. An increase in both the average diameter of the spherical particles and the crystallite size of the nanocrystals occurs with an increase in ammonia concentrations. The Se/Cd atom ratios of CdSe thin films firstly increase and then decrease with an increase in ammonia concentration or sodium selenosulphate concentration. The optical band gap of CdSe thin films decrease with an increase in ammonia concentrations. The kinetics and reaction mechanism of the CdSe nanocrystalline thin films during deposition are discussed. [Copyright &y& Elsevier]

Abstract: Tissue-specific stem cells can be coaxed or harvested for tissue regeneration. In this study, we identified and characterized a new type of stem cells from the synovial membrane of knee joint, named neural crest cell-like synovial stem cells (NCCL-SSCs). NCCL-SSCs showed the characteristics of neural crest stem cells: they expressed markers such as Sox10, Sox17 and S100β, were clonable, and could differentiate into neural lineages as well as mesenchymal lineages, although NCCL-SSCs were not derived from neural crest during the development. When treated with transforming growth factor β1 (TGF-β1), NCCL-SSCs differentiated into mesenchymal stem cells (MSCs), lost the expression of Sox17 and the differentiation potential into neural lineages, but retained the potential of differentiating into mesenchymal lineages. To determine the responses of NCCL-SSCs to microfibrous scaffolds for tissue engineering, electrospun composite scaffolds with various porosities were fabricated by co-electrospinning of structural and sacrificial microfibers. The increase in the porosity in microfibrous scaffolds enhanced cell infiltration in vitro and in vivo, but did not affect the morphology and the proliferation of NCCL-SSCs. Interestingly, microfibrous scaffolds with higher porosity increased the expression of chondrogenic and osteogenic genes but suppressed smooth muscle and adipogenic genes. These results suggest that the differentiation of NCCL-SSCs can be controlled by both soluble chemical factors and biophysical factors such as the porosity of the scaffold. Engineering both NCCL-SSCs and scaffolds will have tremendous potential for tissue regeneration. [Copyright &y& Elsevier]

Abstract: Electrospun scaffolds are used extensively in tissue-engineering applications as they offer a cell-friendly microenvironment. However, one major limitation is the dense fibers, small pore size and consequently poor cell infiltration. Here, we employ a femtosecond (FS) laser system to ablate and create microscale features on electrospun poly(l-lactide) (PLLA) nanofibrous scaffolds. Upon determining the ablation parameters, we pattern structured holes with diameters of 50, 100 and 200μm and spacings of 50 and 200μm between adjacent holes on the scaffolds. The elastic moduli of ablated scaffolds decrease with the decrease in spacing and the increase in hole size. Cells seeded on the laser-ablated scaffolds exhibit different morphology but similar proliferation rate when compared with control (non-ablated) scaffold. Furthermore, animal studies indicate that ablated scaffolds facilitate endothelial cell ingrowth as well as drastically increase M2 macrophage and overall cell infiltration. These findings demonstrate that FS laser ablation can be used to increase cell infiltration into nanofibrous scaffolds. Laser ablation not only can create desired features in micrometer length scale but also presents a new approach in the fabrication of three-dimensional porous constructs for tissue engineering. [Copyright &y& Elsevier]

The catalysts modified with hydrophobic organic groups can quickly remove water from the surface of the catalyst. Consequently, the oxidation of copper species and the growth of copper particles are inhibited, while the catalytic stability of methanol synthesis in the presence of water is improved. [Display omitted] • Cu species oxidation and its particle growth induced by water lead to the deactivation of Cu-based catalyst. • The hydrophobic modification is capable of inhibiting water approach to active site, then improving catalyst stability. • Organic group with longer chain also acts as a physical barrier in preventing Cu particles migration and aggregation. Improving the stability of Cu-based catalysts, especially in the presence of water, has always been a great challenge. The hydrophobization strategy and effects on the catalyst surface property and catalytic performance deserve rigorous investigations. Herein, the hydrophobic modified silica was introduced as a support for CuZn catalyst to hinder the adsorption of water on active sites of Cu-based catalysts, thereby improving its stability. And silane agents (methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane) were selected to modify the SiO 2 surface by a reaction between the silane agent and the hydroxyl groups on the silica surface. After modification, the catalysts exhibited the better stability for methanol synthesis in the presence of water. FT-IR, BET, H 2 -TPR, XRD, TEM, XPS characterization were employed to determine the surface physical properties, reduction properties, crystal structure and particle size of the catalysts before and after the reaction. The results showed that water can simultaneously cause the oxidation and growth of Cu species resulting in the deactivation of Cu-based catalyst. However, the introduction of hydrophobic groups reduced the contact time between water and the active center, which prevented the growth and oxidation of Cu species, thus improving the catalyst stability. [ABSTRACT FROM AUTHOR]

Abstract: In this study, a facile solvothermal method was proposed to grow Cu2ZnSnS4 (CZTS) thin films directly on transparent conductive fluorine-doped tin oxide (FTO) substrates. In the solvothermal fabrication process, precursors of hexadecyl trimethyl ammonium bromide, copper (II) chloride dihydrate, tin (II) chloride dehydrate, zinc (II) chloride, thiourea and ethanol were used. The morphology, crystallographic structure, chemical composition and optical band gap of CZTS thin films were investigated using scanning electronic microscope (SEM), X-ray diffraction (XRD), Raman spectroscopy, energy dispersive spectrometry (EDS) and UV–vis–NIR spectrophotometer, respectively. It is revealed that Cu2ZnSnS4 thin films are in kesterite phase, composed of a large number of uniform sphere-like particles with an average diameter of about 530nm. The optical band gap is found to be 1.51eV. It is believed that both the similar tetragonal structure and small lattice mismatch between the FTO substrate and Cu2ZnSnS4 play a key role in promoting the epitaxial nucleation and growth of the Cu2ZnSnS4 thin films on FTO substrates. [Copyright &y& Elsevier]

Abstract: With the advances of nanotechnology in recent years, our understanding of the therapy of cancers has deepened and the development of new technologies for cancer diseases has emerged. Here, with the recent discoveries of nanomagnetic fluids as well as microgravity effects upon cancerous cells, we suggest an innovative method of treating tumor using magnetic fluid-modeled microgravity. Magnetic fluids are delivered by outside magnetic field to tumor issue either intravenously or through direct injection, and this is followed by application of an uniform external magnetic field that causes microgravity. The modeled microgravity is to inhibit cancerous cells growth and invasion. [Copyright &y& Elsevier]

The goal of the letter is to reduce the manufacturing and alignment difficulty of a large-scale optical system with a real exit pupil on the premise of ensuring the high-quality imaging. An optical system residual aberration correction method by inserting a quasi-planar freeform mirror (QFM) near the exit pupil position is proposed, and here we define the residual aberration is caused by the reduced tolerance of the manufacturing and alignment. By correction analysis, the mathematical model with the QFM sensitivity matrix as the core has been established. In order to verify the residual aberration correction effectiveness and method of the QFM, a set of real manufactured mirrors shape errors and mirrors positions misalignments are introduced on a well-designed three-mirror-anastigmatic (TMA) system with an aperture of 2 meters, a focal ratio of f/12 and a field of view (FOV) of 1.2° to simulate optical system imaging quality damaged condition, and these errors cause the system imaging degeneration to RMS wavefront error (WFE) 0.331λ. Based on the QFM correction method, the system RMS WFE is corrected from the damaged imaging quality 0.331λ to 0.062λ. The QFM tolerance analysis shows that the QFM has looser precision requirements of manufacturing and alignment. By the verification, it shows this method can correct system residual aberration which caused by mirror manufacturing and alignment errors well at one time, and the TMA system has become less strict in manufacturing and alignment requirements by this way than before. The QFM correction ability and the correction method are effective. [ABSTRACT FROM AUTHOR]

Does routine clinical practice require an increase in the resolution of preimplantation genetic testing for aneuploidies (PGT-A) to detect segmental aneuploidies ≤5 Mb? This retrospective study analysed 963 trophectoderm biopsies from 346 couples undergoing PGT between 2019 and 2023. Segmental aneuploidies ≥1 Mb were reported. The characteristics, clinical interpretation and concordance of segmental aneuploidies ≤5 Mb were analysed. The incidence of segmental aneuploidies was 15.1% (145/963) in blastocysts, with segmental aneuploidies of ≤5 Mb accounting for 2.3% (22/963). The size of the segmental aneuploidies showed a skewed distribution. Segmental aneuploidies ≤5 Mb were found to occur more frequently on the q arm of the chromosome, compared with the p arm. Losses of ≤5 Mb segmental aneuploidies were more prevalent than gains, with 17 deletions compared with 5 duplications. Of the segmental aneuploidies, 63.6% (14/22) ≤5 Mb were de novo , and 50.0% (7/14) of de-novo segmental aneuploidies were pathogenic/likely pathogenic (P/LP) copy number variations, accounting for 0.7% of 963 blastocysts. For blastocysts carrying ≤5 Mb segmental aneuploidies, a re-analysis of back-up biopsy samples showed that 35.7% of de-novo segmental aneuploidies (5/14) were not detected in the back-up samples. Cases were reported in which prenatal diagnosis (amniocentesis) revealed the absence of embryonic ≤5 Mb segmental aneuploidies detected at the blastocyst stage. The incidence of P/LP de-novo ≤5 Mb segmental aneuploidies in human blastocysts is extremely low. There is no compelling need to increase the resolution of PGT-A to 5 Mb in routine clinical practice. [ABSTRACT FROM AUTHOR]

• PD-1/PD-L1 pathway is an important immunosuppressive mechanism. • CAR-T cells secreting PD-L1 blocking antibody are used for targeted therapy of solid cancer. • Reduce the immunosuppression on solid tumors and improve the curative effect. • It has a good guiding significance for the clinical application. PD-1/PD-L1 pathway caused immunosuppression accounts, at least partly, for the poor therapeutic effect of Chimeric Antigen Receptor T (CAR-T) on solid tumors. In this study, we designed and prepared CAR-T cells that could secrete PD-L1 blocking antibody and target Mesothelin antigen (Sec-MesoCAR-T), to remove the immunosuppressive effect of tumor on CAR-T cells, thereby increasing the therapeutic effect of CAR-T cells on pancreatic cancer. The CAR-T cells that could not secret PD-L1 blocking antibodies (MesoCAR-T) were used as a control. Sec-MesoCAR-T cells showed an enhanced inhibitory effect on BxPC-3 tumor than MesoCAR-T cells in vitro and in vivo. Besides, Sec-MesoCAR-T cells secreted higher level of cytokines including IL-2, IL-6 and IFN-γ in vitro than MesoCAR-T cells. Following injection, there were significantly more CAR-T cells in the peripheral blood of Sec-MesoCAR-T group than that of MesoCAR-T group. This work demonstrated that the PD-L1 antibody secreted by Sec-MesoCAR-T cells relieved the immunosuppressive effect of pancreatic cancer on CAR-T cells and improved the anti-tumor activity of CAR-T cells, which has a good guiding significance for the clinical application of CAR-T cells in treating solid tumors. [ABSTRACT FROM AUTHOR]

Can preimplantation genetic testing for structural rearrangement (PGT-SR) based on low-coverage next-generation sequencing (NGS) accurately discriminate between normal and carrier embryos of reciprocal translocation (RecT) and Robertsonian translocation (RobT)? A total of 109 couples with RecT or RobT were included in this study. The ages, bad obsteric histories (BOH), blood karyotype and IVF cycle information, including the number of cumulus–oocyte complexes, metaphase II oocytes, two pronuclei oocytes and blastocysts were recorded. 0.1 × whole genome sequencing (WGS) of embryos followed by copy number variation (identifying unbalanced/balanced) and 2 × WGS of parents and embryos followed by haplotype analysis (discriminating between normal and carrier) were carried out in PGT-SR cycles. The embryos without translocation were transferred and clinical outcomes evaluated. Among all the couples in this study, 67 patients had RecT and 42 had RobT. After unbalanced and balanced detection, 103 balanced embryos underwent a further normal and carrier discrimination procedure, and 53 normal embryos were identified. Finally, 32 normal embryos were transferred, with an ongoing pregnancy rate of 46.88% (15/32). All ongoing pregnancies underwent amniocentesis, and the amninocentesis karyotyping results showed 100% concordance with PGT-SR diagnosis. Our low-coverage NGS-based PGT-SR method can accurately discriminate between normal and carrier status of balanced embryos. The method is cost-effective and has broad clinical applicability. [ABSTRACT FROM AUTHOR]