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High-quality antiferromagnetic Mott insulator thin films of LaTiO3 (LTO) were epitaxially grown onto SrTiO3 (STO) (110) substrates using the pulsed laser deposition. The LTO/STO heterostructures are not only highly conducting and ferromagnetic, but also show Kondo effect, Shubnikov-de Haas (SdH) oscillations with a nonzero Berry phase of π, and low-field hysteretic negative magnetoresistance (MR). Angle-dependent SdH oscillations and a calculation of the thickness of the interfacial conducting layer indicate the formation of a 4-nm high mobility two-dimensional electron gas (2DEG) layer at the interface. Moreover, an amazingly large low-field negative MR of ∼61.8% is observed at 1.8 K and 200 Oe, which is approximately one to two orders of magnitude larger than those observed in other spin-polarized 2DEG oxide systems. All these results demonstrate that the 2DEG is spin-polarized and the 4-nm interfacial layer is ferromagnetic, which are attributed to the presence of magnetic Ti3+ ions due to interfacial oxygen vacancies and the diffusion of La3+ ions into the STO substrate. The localized Ti3+ magnetic moments couple to high mobility itinerant electrons under magnetic fields, giving rise to the observed low-field MR. Our work demonstrates the great potential of antiferromagnetic titanate oxide interface for designing spin-polarized 2DEG and spintronic devices. [ABSTRACT FROM AUTHOR]

Alternaria foliar diseases are important factors that pose a significant threat to yield in solanaceous crops. To clarify the diversity of large‐spored Alternaria species in China, diseased leaves of three solanaceous vegetables (potato, tomato and eggplant) were collected and used for fungal isolation. In total, 67 strains representing six species in section Porri of Alternaria were isolated, based on morphological characterizations and multilocus phylogenetic analyses. There were three known species (A. blumeae, A. linariae and A. solani), one new record of A. argyroxiphii and two new species, A. melongenicola sp. nov. and A. yichangensis sp. nov. The sequence analyses encompassed the internal transcribed spacer region of rDNA (ITS), glyceraldehyde‐3‐phosphate dehydrogenase (GAPDH), Alternaria major allergen (Alt a 1), translation elongation factor 1‐α (TEF1) and RNA polymerase second largest subunit (RPB2). To confirm pathogenicity, 15 representative strains were evaluated for their virulence under greenhouse conditions. The results revealed that they were able to induce leaf spot symptoms on potato, tomato and eggplant plants with a range of aggressive abilities. The present study provides a basis for the recognition and management of Alternaria foliar diseases. [ABSTRACT FROM AUTHOR]

In September 2019, two diseased plants of Campsis grandiflora showing the main symptom of witches' ‐broom (CgWB) were found in a nursery garden in Yangling, Shaanxi province, China. Partial 16S ribosomal RNA (F2nR2 region) and ribosomal protein (rp) genes of phytoplasmas were generated from the symptomatic plants by PCR amplification, and phytoplasma bodies were observed in the sieve tube elements of the CgWB samples under a transmission electron microscope, indicating phytoplasma infection in the two CgWB plants. Restriction fragment length polymorphism analysis of the F2nR2 region and similarity coefficient results suggested that the two associated phytoplasmas belong to two novel subgroups of 16SrI (aster yellows) group, designated as AK and AL. On the reconstructed phylogenetic trees based on F2nR2 regions and rp genes of phytoplasmas, respectively, the CgWB‐associated phytoplasmas clustered together with members of 16SrI subgroups. This was the first record of phytoplasmas infecting C. grandiflora worldwide. [ABSTRACT FROM AUTHOR]

Ten varieties of potted apple were subjected to thermotherapy coupled with in vitro meristem culture and in vivo shoot-tip grafting. Using reverse transcription-polymerase chain reaction assays prior to treatment, all treated apple varieties were infected by more than two viruses, and nine of ten varieties were infected by Apple chlorotic leaf spot virus ( ACLSV), Apple stem pitting virus ( ASPV) and Apple stem grooving virus ( ASGV). After treatment, the survivals of the two methods were more different. Total survival rates of the seven apple varieties ( YF9, XYF3, X2001, GL, HF, A123 and ZZ5) treated by thermotherapy coupled with in vitro meristem culture were 25.9% (14/54). The survival rate of YF9, XYF3, X2001, GL, YF6, JJ and XNH treated by thermotherapy coupled with in vivo shoot-tip grafting was from 33.3% to 75.0%, and the average rate (63.0%, 34/54) was twice than that of meristem culture. The virus-free apple plants were acquired only from in vitro variety HF and A123, and the elimination rate of A123 was highest, up to 71.4% (5/7). Fourteen apple survival grafting plants from five varieties ( YF9, XYF3, X2001, YF6 and XNH) were detected virus-free. The average elimination rate of the meristem culture and shoot-tip grafting was very close, 42.9% (6/14) and 41.2% (14/34), respectively. [ABSTRACT FROM AUTHOR]

In 2011, typical symptoms suggestive of phytoplasma infection such as reddening of leaves were observed in peach trees in Fuping, Shaanxi Province, China. Phytoplasma-like bodies were observed by transmission electron microscope in the petiole tissues of symptomatic peach trees. Products of c. 1.2 kb were generated from all symptomatic peach leaf samples by a nested polymerase chain reaction using phytoplasma universal primer pairs P1⁄P7 and R16F2n⁄R16R2, whereas no such amplicon was obtained from healthy samples. Results of phylogenetic analysis and restriction fragment length polymorphism suggested that the phytoplasma associated with such peach red leaf disease was a member of subgroup 16SrI-C. To our knowledge, this is the first record of 16SrI-C subgroup phytoplasma occurred in peach tree in China. [ABSTRACT FROM AUTHOR]

Preparation of trisubstituted alkenes from low-activity β-diketones and aldehydes with aluminum chloride as catalyst has been studied. The frequently used catalyst AlCl 3 is used for the first time to promote this condensation. The procedure is a convenient, low toxicity, and highly efficient method for industrial synthesis of trisubstituted alkenes in high yield. [ABSTRACT FROM AUTHOR]

Spin polarization of two-dimensional electron gas (2DEG) at the interface of EuTiO 3 /SrTiO 3 (STO) heterostructures has been theoretical predicted and experimentally observed via x-ray magnetic circular dichroism and polarized x-ray absorption spectroscopy, which, however, is lack of magnetotransport evidence. Here, we report the fabrication of high-quality EuTiO 3 /STO heterostructures by depositing antiferromagnetic insulating EuTiO 3 thin films onto STO substrates. Shubnikov-de Haas oscillation, Hall, and magnetoresistance (MR) measurements show that the interface is not only highly conducting, with electron mobility up to5.5×103cm 2 V -1 s -1 at 1.8 K, but also shows low-field hysteretic MR effects. MR of ∼9% is observed at 1.8 K and 20 Oe, which is one order of magnitude higher than those observed in other spin-polarized 2DEG oxide systems. Moreover, the heterostructures show ferromagnetic hysteresis loops. These results demonstrate that the high-mobility 2DEG is spin polarized, whose origin is attributed to the interfacial Ti 3+ -3 d states due to oxygen deficiency and the exchange interactions between interfacial Eu spins and itinerant Ti-3 d electrons., (© 2023 IOP Publishing Ltd.)

In order to understand the colonization pattern of Bacillus subtilis JL4 both on and inside grape leaves, and its control of grape downy mildew, a shuttle vector pGFP78, carrying the GFP gene, was transformed into B. subtilis JL4, and a GFP-labelled transformant designated as JL4-gfp was obtained successfully. The stability of the marker and antagonistic activity to Plasmopara viticola of JL4-gfp were tested. JL4-gfp was spray inoculated on grape leaves in a vine yard and colonization of the leaves was investigated by dilution plating on selective medium. Leaves treated with JL4-gfp were collected and taken to the laboratory for inoculation of a sporangial suspension of P. viticola, to determine its control effect on grape downy mildew. The green fluorescence of the marked strain was stable for at least 10 subcultures, and JL4-gfp maintained wild type antagonistic activity against P. viticola. JL4-gfp was recovered from the grape leaves by dilution plating on medium supplemented with antibiotics. Numbers recovered from the leaf surface of grape leaves were 3.6×10 5 , 2.7×10 5 and 3.1×10 3 CFU·g -1 at 0, 3 and 7 days after inoculation, and the population density inside the leaf tissue reached a maximum of 9.6×10 4 CFU·g -1 at 3 days after inoculation, but could not be recovered after 14 days. The efficiency of downy mildew control by the marked strain was more than 88.0% at 3 days after inoculation, but no significant control effect was observed after 7 days. Our results suggested that there was a positive correlation between the JL4-gfp population density and control efficiency of grape downy mildew, and a threshold colonization level at 10 5 CFU·g -1 was a prerequisite for this Bacillus strain to present efficient control effects.

Objective: To evaluate the effects of the combination of basic fibroblast growth factor (bFGF), transforming growth factor-Β1 (TGF-Β1), bone marrow mesenchymal stem cells (BMSCs), and temperature-responsive chitosan hydrogel (TCH) gel on the repair of degenerative intervertebral disc in rat models., Methods: Rat models of intervertebral disc degeneration were established by acupuncture. The degenerative effects were observed under magnetic resonance imaging (MRI). The BMSCs was cultured in vitro and then transfected by adenovirus with enhanced green fluorescent protein to make it carry the gene of enhanced green fluorescent protein,which functioned as fluorescence labeling. The SD rat models of intervertebral disc degeneration were divided into four groups: group A, treated with the combination of bFGF, TGF-Β1,BMSCs,and TCH gel; group B, treated with the combination of BMSCs and TCH gel;group C, treated with the combination of bFGF,TGF-Β1, and TCH gel;and group D, treated with PBS buffer solution. After the corresponding reagents were injected into the degenerative intervertebral discs of each group, the rats were cultivated for another four weeks and then the repair effects of the intervertebral discs were observed under MRI. Furthermore,the intervertebral discs of each group were taken out and observed by HE and Masson staining. The nucleus pulposus was aspirated and the expressions of aggrecan,collagen 2,Sox-9,and collagen I of nucleus pulposus of each group were tested by reverse transcription polymerase chain reaction and Western blot., Results: The transplanted BMSCs survived in the intervertebral disc and differentiated into nucleus pulposus-like cells. MRI showed that:the signal intensity of the nucleus pulposus of group A was much higher than that of the rest groups, the signal intensity of group B was higher than that of group C, and the signal intensity of group D was the lowest,in which the dura mater spinalis was in compression and the spinal cord changed in beaded shape. The differences of the Pfirrmann grading among the four groups had statistical significance (P<0.05). The results of the HE and Masson stains showed:the intervertebral disc of group A was well-structured,the quantity of nucleus pulposus cells was larger than that of the other three groups,and the boundary between the nucleus pulposus and the annulus fibrosus was clearly defined;the quantity of the nucleus pulposus cells of group B was larger than that of group C, and the broken annulus fibrosus was not observed in group B, while the broken annulus fibrosus could be observed in group C; and, the nucleus pulposus cells of group D were replaced by fibrous tissue. The results of the reverse transcription polymerase chain reaction and Western blot tests showed that,in terms of the expressions of aggrecan,collagen 2 and Sox-9,group A was the highest, followed by group B,group C,and group D (P<0.05); in terms of the expression of collagen 1,there was no obvious difference among these four groups (P>0.05)., Conclusions: The transplanted BMSCs can survive in the degenerative intervertebral disc and differentiate into nucleus pulposus-like cells. The combination of bFGF, TGF-Β1, BMSCs,and TCH gel has obvious repair effect on the degenerative intervertebral discs. The effect of the combination of BMSCs and TCH gel on transplantation therapy of the degenerative intervertebral discs is better than that of the combination of bFGF, TGF-Β1 and TCH gel but worse than that of the combination of bFGF, TGF-Β1, BMSCs, and TCH gel.

A method based on microwave-assisted extraction (MAE) has been developed for the determination of paclitaxel and five related taxoids, namely 10-deacetylbaccatin III (10-DAB III), cephalomannine, 10-deacetylpaclitaxel (10-DAT), 7-xyl-10- deacetylpaclitaxel (7-xyl-10-DAT), and 7-epi-10-deacetylpaclitaxel (7-epi-10-DAT) in Taxus species in this study. The influential parameters of the MAE procedure were optimized, and the optimal conditions were as follows: extraction solvent 80% ethanol solution, solid/liquid ratio 1:10 (g/mL), temperature 50 degrees C, and three extraction cycles, each cycle 10 min. The method validation for LC-MS/MS analysis was performed. The LOD and LOQ were 3.16-9.20 and 12.20-30.45 ng/mL, respectively. Repeatability and reproducibility for the six taxiods with RSD ranged from 2.78 to 3.85% and from 5.26 to 6.60%. The recoveries of the method for the six taxoids were 92.6-105.6%. The developed MAE-LC-MS/MS method was also successfully applied to determine the contents of six taxoids in different Taxus species.

It is very difficult to diagnosis osteoarthritis in the early stage, due to the slow development of the disease, no symptoms occures, and no X-ray findings in the early stage, it is difficult to early diagnosis with the traditional diagnostic methods, resulting in the poor treatment outcome, and even some patients develop joint deformity, activity limitation, and must take an operation, it brought great pain and heavy financial burden to patients. How to early diagnosis of articular cartilage injury become difficult now. Some scholars suggest that to those suspected patients, the arthroscopic diagnosis must be taken. Although the small trauma and quick recover, the method of operation has trauma, not only increase the suffering of the patients, but the treatment is very expensive, make the patients finch. A large number of domestic and foreign scholars to study patients with OA to find the ideal fluid biological markers (BM) to reflect articular cartilage metabolism, and revealed disease activity or prognosis. The CTX-II can reflect degradation of the articular cartilage.