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Objective. Transplantation of bone marrow-derived mesenchymal stem cells (BMSCs) remains a hopeful therapeutic approach for bone defect reconstruction. Herein, we investigated the effects and mechanisms of leukemia inhibitory factor (LIF) in the function and viability of hypoxic BMSCs as well as bone defect repair. Methods. The effects of LIF on apoptosis (flow cytometry, TUNEL staining), mitochondrial activity (JC-1 staining), proliferation (colony formation, EdU staining), and differentiation (CD105, CD90, and CD29 via flow sorting) were examined in hypoxic BMSCs. LIF, LIFR, gp130, Keap1, Nrf2, antioxidant enzymes (SOD1, catalase, GPx-3), bone-specific matrix proteins (ALP, BSP, OCN), PI3K, and Akt were detected via immunoblotting or immunofluorescent staining. BMSCs combined with biphasic calcium phosphate scaffolds were implanted into calvarial bone defect mice, and the therapeutic effect of LIF on bone defect was investigated. Results. Hypoxic BMSCs had increased apoptosis and oxidative stress and reduced mitochondrial activity. Additionally, LIF, LIFR, and gp130 were upregulated and PI3K/Akt activity was depressed in hypoxic BMSCs. Upregulated LIF alleviated apoptosis and oxidative stress and heightened mitochondrial activity and PI3K/Akt signaling in hypoxic BMSCs. Additionally, LIF overexpression promoted self-renewal and osteogenic differentiation of BMSCs with hypoxic condition. Mechanically, LIF facilitated self-renewal and differentiation as well as attenuated oxidative stress of BMSCs through enhancing PI3K/AKT signaling activity. Implantation of LIF-overexpressed BMSC-loaded BCP scaffolds promoted osteogenesis as well as alleviated oxidative stress and apoptosis through PI3K/Akt signaling. Conclusion. Our findings demonstrate that LIF facilitates self-renewal and differentiation and attenuates oxidative stress of BMSCs by PI3K/AKT signaling.

Chaetomium fungi produce a diversity of bioactive compounds. Chaetomium cochliodes SD-280 possesses 91 secondary metabolite gene clusters and exhibits strong antibacterial activity. One of the active compounds responsible for that activity, chetomin, has a minimum inhibitory concentration (MIC) for anti-methicillin-resistant Staphylococcus aureus (MRSA) of 0.05 μg/mL (vancomycin: 0.625 μg/mL). This study demonstrated that the addition of glutathione (GSH) can enhance chetomin yield dramatically, increasing its production 15.43-fold. Following genome sequencing, cluster prediction, and transcriptome and proteome analyses of the fungus were carried out. Furthermore, a relatively complete chetomin biosynthetic gene cluster was proposed, and the coding sequences were acquired. In the cluster of GSH-treated cells, proteome analysis revealed two up-regulated proteins that are critical enzymes for chetomin biosynthesis. One of these enzymes, a nonribosomal peptide synthetase (NRPS), was heterologously expressed in Aspergillus nidulans, and one of its metabolites was determined to be an intermediate in the chetomin biosynthetic pathway. We present here, to our knowledge, the first experimental evidence that chetomin exhibits strong bioactivity against MRSA. Our work also provides extensive insights into the biosynthetic pathway of chetomin, in particular identifying two key enzymes (glutathione S-transferase (CheG) and NRPS (CheP)) that substantially up-regulate chetomin. These mechanistic insights into chetomin biosynthesis will provide the foundation for further investigation into the anti-pathogenic properties and applications of chetomin. KEY POINTS: • Chetomin exhibits strong anti-MRSA activity with MIC of 0.05 μg/mL. • Addition of glutathione improved the yield of chetomin by 15.43-fold. • CheG and CheP involved in the chetomin biosynthesis were revealed for the first time.

Pregnancy and lactation are a window period during which interventions on mothers bring beneficial effects to newborns.

The accurate measurement of human joint torque is one of the research hotspots in the field of biomechanics. However, due to the complexity of human structure and muscle coordination in the process of movement, it is difficult to measure the torque of human joints in vivo directly. Based on the traditional elbow double-muscle musculoskeletal model, an improved elbow neuromusculoskeletal model is proposed to predict elbow muscle torque in this paper. The number of muscles in the improved model is more complete, and the geometric model is more in line with the physiological structure of the elbow. The simulation results show that the prediction results of the model are more accurate than those of the traditional double-muscle model. Compared with the elbow muscle torque simulated by OpenSim software, the Pearson correlation coefficient of the two shows a very strong correlation. One-way analysis of variance (ANOVA) showed no significant difference, indicating that the improved elbow neuromusculoskeletal model established in this paper can well predict elbow muscle torque.

Chiral imidodiphosphates (IDPs) have emerged as strong Brønsted acid catalysts for many enantioselective processes. However, the dynamic transformation between O,O-syn and O,O-anti conformers typically results in low enantioselectivity. Here we demonstrate that topologies of metal-organic frameworks (MOFs) can be exploited to control IDP conformations and local chiral microenvironments for enantioselective catalysis. Two porous Dy-MOFs with different topologies are obtained from an enantiopure 1,1'-biphenol IDP-based tetracarboxylate ligand. While the ligand adopts a 4- or 3-connected (c) binding mode, all IDPs are rigidified to get only a single O,O-syn conformation and display greatly enhanced Brønsted acidity relative to the free IDP. The MOF with the 4-c IDP that has a relatively less compact shape than the 3-c IDP can be an efficient and recyclable heterogeneous Brønsted acid catalysing the challenging asymmetric O,O-acetalization reaction with up to 96 % enantiomeric excess.

Shikonins (SK) and acetyl-shikonins (acetyl-SK) are known to possess great pharmaceutical potentials however, their ability to disrupt infectious bacterial communication system viz. quorum sensing (QS) remains unexplored. Therefore, the rationale behind this research was to investigate the QS-quenching potential of SK and acetyl-SK against C. violaceum through biofilm formation and violacein production assays. The quantitative evaluation was followed by the investigation of transcript abundance of violacein-regulating genes using RT-qPCR. Quantitative analysis indicated marked inhibition of QS-related traits with more obvious inhibition (87.5% biofilm, and 58% violacein inhibition) with 0.4 mM SK-treatment. Our RT-qPCR results displayed a substantially significant decrease in the expression level of CviR in SK-treated cells. Furthermore, SK treatment resulted in reduced transcript abundance of violacein biosynthetic genes such as vioB, vioC, and vioD. It was found that SK-induced QS inhibition in C. violaceum occurred through CviR down-regulation, which might further potentially disrupt the AHL-CviR receptor interaction. Both SK and acetyl-SK treatments were found to be ineffective against pre-mature biofilms, implying that SK-mediated biofilm attenuation is caused by interference with the expression of genes involved in biofilm attachment. In our study, SK strongly interfered with AHL-regulated physiological attributes while acetyl-SK was effective in inhibiting biofilm formation only. Collectively we found SK as anti-QS agents that mediate C. violaceum QS inhibition and bring new hope in combating C. violaceum infections. In addition, our findings can help prevent drug resistance in microbial pathogens in the future.

Rapid and sensitive detection of various analytes is in high demand. Apart from its application in genome editing, CRISPR–Cas also shows promises in nucleic acid detection applications. To further exploit the potential of CRISPR–Cas for detection of diverse analytes, we present a versatile biosensing platform that couples the excellent affinity of aptamers for broad-range analytes with the collateral single-strand DNA cleavage activity of CRISPR–Cas12a. We demonstrated that the biosensors developed by this platform can be used to detect protein and small molecule in human serum with a complicated background, i.e., the tumor marker alpha fetoprotein and cocaine with the detection limits of 0.07 fmol/L and 0.34 μmol/L, respectively, highlighting the advantages of simplicity, sensitivity, short detection time, and low cost compared with the state-of-the-art biosensing approaches. Altogether, this biosensing platform with plug-and-play design show great potential in the detection of diverse analytes.

Separation of racemic mixtures is of great importance and interest in chemistry and pharmacology. Porous materials including metal-organic frameworks (MOFs) have been widely explored as chiral stationary phases (CSPs) in chiral resolution. However, it remains a challenge to develop new CSPs for reversed-phase high-performance liquid chromatography (RP-HPLC), which is the most popular chromatographic mode and accounts for over 90% of all separations. Here we demonstrated for the first time that highly stable Zr-based MOFs can be efficient CSPs for RP-HPLC. By elaborately designing and synthesizing three tetracarboxylate ligands of enantiopure 1,1'-biphenyl-20-crown-6, we prepared three chiral porous Zr(IV)-MOFs with the framework formula [Zr6O4(OH)8(H2O)4(L)2]. They share the same flu topological structure but channels of different sizes and display excellent tolerance to water, acid, and base. Chiral crown ether moieties are periodically aligned within the framework channels, allowing for stereoselective recognition of guest molecules via supramolecular interactions. Under acidic aqueous eluent conditions, the Zr-MOF-packed HPLC columns provide high resolution, selectivity, and durability for the separation of a variety of model racemates, including unprotected and protected amino acids and N-containing drugs, which are comparable to or even superior to several commercial chiral columns for HPLC separation. DFT calculations suggest that the Zr-MOF provides a confined microenvironment for chiral crown ethers that dictates the separation selectivity.

To better understand the substituent effect of cyclic catalysts on propylene polymerization, a series of cyclic bis(phenoxyimine) titanium catalysts bearing different size substituents at the ortho...

Brassica napus cultivars have little or no primary dormancy; however, they are prone to secondary dormancy induction. Secondary dormant seeds can produce volunteer plants, which can result in genetic contamination, reduced quality and biosafety issues. However, information regarding the molecular mechanism underlying secondary dormancy is limited. The MOTHER OF FT AND TFL1 (MFT) gene, which is evolutionarily conserved in the plant kingdom, acts in a complex gene network in the seed dormancy or germination processes. In this study, we identified four B. napus genes that share high homology with AtMFT, named as BnaMFT. Analyses of cis-acting elements showed that BnaMFT promoters contain multiple seed-specific regulatory elements, and various stress- and hormone-responsive elements. Further experiments validated that BnaMFTs were specifically expressed during seed maturation and in the dry seed, with peaks at 35–42 days after pollination. BnaMFTs were not sufficient for primary dormancy; however, they were significantly enhanced by secondary dormancy induction with PEG6000 treatment. Moreover, BnaMFT transcripts were elevated by treatment with abscisic acid (ABA), which is known to be accumulated during secondary dormancy. These results collectively suggest that increased BnaMFT transcription levels are associated with secondary dormancy induction in an ABA-dependent manner in B. napus.

Precise control over olefin polymerization, especially polymer stereochemistry, through artful catalyst design is attractive and highly challenging. A rigid cyclic framework was first introduced in...

Low temperature germination (LTG) is a key agronomic trait in rice (

Micronutrient metals, such as Mn, Cu, Fe, and Zn, are essential heavy metals for plant growth and development, while Cd is a nonessential heavy metal that is highly toxic to both plants and humans. Our understanding of the molecular mechanisms underlying Cd and micronutrient metal accumulation in plants remains incomplete. Here, we show that OsFWL7, an FW2.2-like (FWL) family gene in Oryza sativa, is preferentially expressed in the root and encodes a protein localized to the cell membrane. The osfwl7 mutation reduces both the uptake and the root-to-shoot translocation of Cd in rice plants. Additionally, the accumulation of micronutrient metals, including Mn, Cu, and Fe, was lower in osfwl7 mutants than in the wildtype plants under normal growth conditions. Moreover, the osfwl7 mutation affects the expression of several heavy metal transporter genes. Protein interaction analyses reveal that rice FWL proteins interact with themselves and one another, and with several membrane microdomain marker proteins. Our results suggest that OsFWL7 is involved in Cd and micronutrient metal accumulation in rice. Additionally, rice FWL proteins may form oligomers and some of them may be located in membrane microdomains.

Micronutrient metals, such as Mn, Cu, Fe, and Zn, are essential heavy metals for plant growth and development, while Cd is a nonessential heavy metal that is highly toxic to both plants and humans. Our understanding of the molecular mechanisms underlying Cd and micronutrient metal accumulation in plants remains incomplete. Here, we show that OsFWL7, an FW2.2-like (FWL) family gene in Oryza sativa, is preferentially expressed in the root and encodes a protein localized to the cell membrane. The osfwl7 mutation reduces both the uptake and the root-to-shoot translocation of Cd in rice plants. Additionally, the accumulation of micronutrient metals, including Mn, Cu, and Fe, was lower in osfwl7 mutants than in the wildtype plants under normal growth conditions. Moreover, the osfwl7 mutation affects the expression of several heavy metal transporter genes. Protein interaction analyses reveal that rice FWL proteins interact with themselves and one another, and with several membrane microdomain marker proteins. Our results suggest that OsFWL7 is involved in Cd and micronutrient metal accumulation in rice. Additionally, rice FWL proteins may form oligomers and some of them may be located in membrane microdomains.

Antigen detection provides particularly valuable information for medical diagnoses; however, the current detection methods are less sensitive and accurate than nucleic acid analysis. The combination of CRISPR/Cas12a and aptamers provides a new detection paradigm, but sensitive sensing and stable amplification in antigen detection remain challenging. Here, we present a PCR-free multiple trigger dsDNA tandem-based signal amplification strategy and a de novo designed dual aptamer synergistic sensing strategy. Integration of these two strategies endowed the CRISPR/Cas12a and aptamer-based method with ultra-sensitive, fast, and stable antigen detection. In a demonstration of this method, the limit of detection was at the single virus level (0.17 fM, approximately two copies/μL) in SARS-CoV-2 antigen nucleocapsid protein analysis of saliva or serum samples. The entire procedure required only 20 min. Given our system's simplicity and modular setup, we believe that it could be adapted reasonably easily for general applications in CRISPR/Cas12a-aptamer-based detection.

Significance Excessive use of antibiotics for patient therapy and livestock results in the selection of pathogenic bacteria resistant to multiple drugs. The spread of multidrug-resistant bacteria into the community is associated with increased morbidity, mortality, and financial burden of health care. We constructed a library of SuFEx-derived arylfluorosulfates that demonstrated potent activities in combating multidrug-resistant bacteria both in vitro and in vivo. Significantly, these arylfluorosulfate analogs show enhanced potency to disrupt bacterial biofilm as well as kill persisters and have a synergistic effect with clinical bactericidal drugs. This study suggests that arylfluorosulfates derived from SuFEx-based modification of phenols could serve as a convenient strategy to search for bactericidal candidates.

CoAPO-5 molecular sieves were synthesized by a novel dynamic method. Crystallization, morphology and surface acidity were investigated by XRD, SEM, and Py-IR in details, and compared with samples prepared by traditional static method. Synthesis conditions, reaction time, temperature and the amount of catalyst were optimized as important parameters. The desulfurization performance of CoAPO-5 catalysts synthesized by two different methods was evaluated and compared. Also, some experiments were carried out to test selectivity and regenerability of CoAPO-5 catalysts synthesized by the dynamic method. Finally, ODS reaction kinetics and mechanism using CoAPO-5 was studied and discussed. Results indicated that dynamic method greatly shortened crystallization time, while kept the same structure and sulfur removal capacity of CoAPO-5. The dynamic synthesis method could be considered as an alternative method to prepare porous molecular sieves.

Effects of transgenic crops on soil microbial communities are important constituents in ecological risk assessment. The Illumina MiSeq sequencing method was employed to examine the effects of transgenic glufosinate-resistant rapeseed and the associated herbicide application on rhizospheric bacterial communities at different growth stages. Our results showed that both transgenic rapeseed and the application of herbicide Basta (active ingredient: glufosinate) had no significant influence on alpha-diversity of rhizospheric bacterial communities. The dominant phyla across all samples were Proteobacteria, Bacteroidetes, Acidobacteria, Gemmatimonadetes and Actinobacteria. These dominant phyla show no remarkable differences under transgenic rapeseed, transgenic rapeseed with glufosinate applied, and non-transgenic acceptor counterpart rapeseed. Nevertheless, they respond differently at different growth stages. These results indicate that community variation was strongly dependent on the growth stage. Therefore, growing glufosinate-resistant transgenic rapeseed line Z7B10 and application of glufosinate herbicide had no adverse effects on the rhizospheric bacterial community composition.

Two methods, PCR and amplicon labeling based, were developed and successfully applied to reliably detect CRISPR/Cas9 induced indels in rice. The use of CRISPR/Cas9 has emerged as a powerful nuclease-based genome editing tool in several model organisms including plants for mutagenesis by inducing precise gene editing through efficient double strand DNA breaks (DSBs) at the target site and subsequent error-prone non-homologous end joining (NHEJ) repair, leading to indel mutations. Different molecular methods including enzymatic mismatch cleavage (EMC), high-resolution melting curve analysis (HRMA) and conventional polymerase chain reaction (PCR) combined with ligation detection reaction (LDR) have been developed to quick identify CRISPR/Cas9 induced mutations. However, their intrinsic drawbacks limit their application in the identification of indel mutants in plants. Here we present two methods (one simple PCR based and the other amplicon labeling based) for effective and sensitive detection of CRISPR/Cas9 induced indels in rice. In PCR-based method, targets were amplified using two pairs of primers for each target locus and visualized on gel electrophoresis, while in amplicon labeling-based method, targets were amplified using tri-primers (with one a universal 6-FAM 5'-labelled) and detected by DNA capillary electrophoresis. Both methods can accurately define indel sizes down to ± 1 bp, and are amenable for high throughput analysis, therefore, will significantly facilitate the identification of indel mutants generated by CRISPR/Cas9 for further functional analysis and breeding in rice and other plants.

Antigen detection provides particularly valuable information for medical diagnoses; however, the current detection methods are less sensitive and accurate than nucleic acid analysis. The combination of CRISPR/Cas12a and aptamers provides a new detection paradigm, but sensitive sensing and stable amplification in antigen detection remain challenging. Here, we present a PCR-free multiple trigger dsDNA tandem-based signal amplification strategy and a de novo designed dual aptamer synergistic sensing strategy. Integration of these two strategies endowed the CRISPR/Cas12a and aptamer-based method with ultra-sensitive, fast, and stable antigen detection. In a demonstration of this method, the limit of detection was at the single virus level (0.17 fM, approximately two copies/μL) in SARS-CoV-2 antigen nucleocapsid protein analysis of saliva or serum samples. The entire procedure required only 20 minutes. Given our system’s simplicity and modular setup, we believe that it could be adapted reasonably easily for general applications in CRISPR/Cas12a-aptamer-based detection.

Environmental conditions, such as photoperiod and temperature, can affect male fertility in plants. While this feature is heavily exploited in rice to generate male-sterile lines for hybrid breeding, the underlying molecular mechanisms remain largely unknown. In this study, we use a transcriptomics approach to identify key genes and regulatory networks affecting pollen maturation in rice anthers in response to different day lengths. A total of 11,726 differentially expressed genes (DEGs) were revealed, of which 177 were differentially expressed at six time points over a 24-h period. GO enrichment analysis revealed that genes at all time points were enriched in transport, carbohydrate, and lipid metabolic processes, and signaling pathways, particularly phytohormone signaling. In addition, co-expression network analysis revealed four modules strongly correlated with photoperiod. Within these four modules, 496 hub genes were identified with a high degree of connectivity to other photoperiod-sensitive DEGs, including two previously reported photoperiod- and temperature-sensitive genes affecting male fertility, Carbon Starved Anther and UDP-glucose pyrophosphorylase, respectively. This work provides a new understanding on photoperiod-sensitive pollen development in rice, and our gene expression data will provide a new, comprehensive resource to identify new environmentally sensitive genes regulating male fertility for use in crop improvement.

Although Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR-associated 9 (Cas9) system has been widely used for basic research in model plants, its application for applied breeding in crops has faced strong regulatory obstacles, due mainly to a poor understanding of the authentic output of this system, particularly in higher generations. In this study, different from any previous studies, we investigated in detail the molecular characteristics and production performance of CRISPR/Cas9-generated SD1 (semi-dwarf 1) mutants from T2 to T4 generations, of which the selection of T1 and T2 was done only by visual phenotyping for semidwarf plants. Our data revealed not only on- and off-target mutations with small or lager indels but also exogenous elements in T2 plants. All indel mutants passed stably to T3 or T4 without additional modifications independent on the presence of Cas9, while some lines displayed unexpected hereditary patterns of Cas9 or some exogenous elements. In addition, effects of various SD1 alleles on rice height and yield differed depending on genetic backgrounds. Taken together, our data showed that the CRISPR/Cas9 system is effective in producing homozygous mutants for functional analysis, but it may be not as precise as expected in rice, and that early and accurate molecular characterization and screening must be carried out for generations before transitioning of the CRISPR/Cas9 system from laboratory to field.

A multiplex ligation-dependent probe amplification (MLPA)-based method was developed and successfully utilized to efficiently detect both CRISPR/Cas9-induced and naturally occurred mutations in rice. The site-specific nuclease-based CRISPR/Cas9 system has emerged as one of the most efficient genome editing tools to modify multiple genomic targets simultaneously in various organisms, including plants for both fundamental and applied researches. Screening for both on-target and off-target mutations in CRISPR/Cas9-generated mutants at the early stages is an indispensable step for functional analysis and subsequent application. Various methods have been developed to detect CRISPR/Cas9-induced mutations in plants. Still, very few have focused on the detection of both on- and off-targets simultaneously, let alone the detection of natural mutations. Here, we report a multiplex capable method that allows to detect CRISPR/Cas9 induced on- and off-target mutations as well as naturally occurred mutation based on a multiplex ligation-dependent probe amplification (MLPA) method. We demonstrated that unlike other methods, the modified target-specific MLPA method can accurately identify any INDELs generated naturally or by the CRISPR/Cas9 system and that it can detect natural variation and zygosity of the CRISPR/Cas9-generated mutants in rice as well. Furthermore, its high sensitivity allowed to define INDELs down to 1 bp and substitutions to a single nucleotide. Therefore, this sensitive, reliable, and cheap method would further accelerate functional analysis and marker-assisted breeding in plants, including rice.

The FW2.2-like (FWL) genes encode cysteine-rich proteins with a placenta-specific 8 domain. They play roles in cell division and organ size control, response to rhizobium infection, and metal ion homeostasis in plants. Here, we target eight rice FWL genes using the CRISPR/Cas9 system delivered by Agrobacterium-mediated transformation. We successfully generate transgenic T0 lines for 15 of the 16 targets. The targeted mutations are detected in the T0 lines of all 15 targets and the average mutation rate is found to be 81.6%. Transfer DNA (T-DNA) truncation is a major reason for the failure of mutagenesis in T0 plants. T-DNA segregation analysis reveals that the T-DNA inserts in transgenic plants can be easily eliminated in the T1 generation. Of the 30 putative off-target sites examined, unintended mutations are detected in 13 sites. Phenotypic analysis reveals that tiller number and plant yield of OsFWL4 gene mutants are significantly greater than those of the wild type. Flag leaves of OsFWL4 gene mutants are wider than those of the wild type. The increase in leaf width of the mutants is caused by an increase in cell number. Additionally, grain length of OsFWL1 gene mutants is higher than that of the wild type. Our results suggest that transgene-free rice plants with targeted mutations can be produced in the T1 generation using the Agrobacterium-mediated CRISPR/Cas9 system and that the OsFWL4 gene is a negative regulator of tiller number and plant yield.

We performed an international collaborative ring trial to validate gene-specific loop-mediated isothermal amplification (LAMP) assays targeting four exogenous transgenes commonly utilized in the development of genetically modified (GM) crops: bar, pat, cp4-epsps, and Cry1Ac, respectively. A total of 12 laboratories participated in the ring trial and returned their test results. Statistical analysis of the returned results showed high specificity and low limit of detection (LOD) of the four LAMP assays. The LOD for cp4-epsps, Cry1Ac, bar and pat genes assay was 5, 10, 20 and 20 haploid genome equivalents (HGE), respectively. Furthermore, good performance of the four assays was further demonstrated in the analysis of practical samples in which all participating laboratories returned expected and accurate test results. Altogether, the ring trial results confirmed that the four gene-specific LAMP assays can be utilized for quick screening of transgenic traits in routine laboratory analysis.

A series of binuclear nickel phenoxyiminato catalysts with different linkers and fluorine substituents were efficiently synthesized. Binuclear nickel catalysts with rigid linkers showed higher catalytic activity and thermal stability in ethylene polymerization and produced polymers with higher molecular weight possibly due to the larger steric hindrance and metal-metal synergistic effect. The introduction of fluorine atoms on the N-terphenyl moity also enhanced polymerization activity and molecular weight of polymer due to the electronic effect of fluorine atoms.

A series of macrocyclic multinucleating phenoxyimine ligands and the corresponding neutral binuclear (2-Ni2) and trinuclear (3-Ni3) nickel catalysts have been efficiently synthesized. The trinuclear nickel complex 3-Ni3 showed high activity, high thermal stability, and slow chain transfer in ethylene polymerization, thus producing polyethylene with high molecular weight and low branch density. Highly regiospecific and isospecific polymerization of propylene was also achieved with 3-Ni3, generating regioregular and highly isotactic propylene with high Tm and crystallinity. This is the first example of regio- and stereocontrolled propylene polymerization promoted by nickel phenoxyimine catalysts. Statistical analysis suggested selective 1,2-insertion and enantiomorphic site control mechanism in the chain propagation step, likely caused by the unique steric effect of macrocyclic ligands and the potential cooperative effect.

To examine whether there were significant differences in sleep during weekdays/weekends and whether the intra-individual variability in sleep was related to glycaemic control in patients with type 2 diabetes.Correlational, longitudinal design.Data were collected between February 2017-January 2018. In all, 56 adults with type 2 diabetes were included (60.7 years, 55.4% female). Sleep was measured using the Consensus Sleep Diary over 8 days. Intra-individual variability of sleep was calculated as the standard deviation of sleep variables. Standard deviations of sleep duration, sleep efficiency, sleep quality, and mid-sleep time were obtained. Glycaemic control was measured by haemoglobin A1C. Paired t test and multiple regression analysis were used.Overall, there were no differences in sleep parameters between weekdays and weekends. Participants slept 20 min more over the weekends than during weekdays. The mid-sleep time during weekends was about 35 min later than during weekdays. Intra-individual variability of sleep duration and mid-sleep ranged from 27.6-167.4 min and 13-137 min, respectively. Controlling for covariates (e.g., distress, symptoms, and self-care), larger variability in sleep duration, and mid-sleep were significantly related to higher A1C levels.Diabetes educators are recommended to include the assessment of intra-individual variability in sleep. Maintaining a regular sleep habit (e.g., sleep duration and sleep timing) should be highlighted during patient education.Intra-individual variability in sleep is an alternative dimension for sleep assessment. This study examined whether intra-individual variability in sleep was related to glycaemic control in an older sample of type 2 diabetes patients using a sleep diary across 8 days. This sample had a similar sleep pattern during weekdays and weekends. Larger intra-individual variabilities in sleep duration and mid-sleep time were independently related to worse glycaemic control. Diabetes patients are recommended to maintain a regular sleep routine.目的: 检查II型糖尿病患者工作日/周末睡眠是否存在显著差异,以及个体内部睡眠差异是否与血糖控制有关。 设计: 相关纵向设计。 方法: 采集2017年2月至2018年1月的数据。共有56例II型糖尿病成人患者(60.7岁,55.4%为女性)参与此项研究。使用认知睡眠日记来记录8天的睡眠情况。个体内部睡眠差异被计算为睡眠变量的标准差。计算睡眠时间、睡眠效率、睡眠质量和平均睡眠时间的标准差。通过血红蛋白A1C测定血糖控制。采用配对t检验和多元回归分析。 结果: 总体而言,工作日和周末的睡眠参数没有差异。受试者周末睡眠时间比工作日多20分钟。周末的平均睡眠时间比工作日晚约35分钟。个体内部睡眠差异和平均睡眠时间范围分别为27.6~167.4分钟和13~137分钟。协变量(如抑郁、病症和自我护理)控制、较大的睡眠持续时间差异和平均睡眠时间与较高的血红蛋白A1C水平显著相关。 结论: 建议糖尿病教育工作者考虑评估个体内部睡眠差异。在患者教育期间,应重点强调保持规律的睡眠习惯(如睡眠持续时间和睡眠时间)。 影响: 个体内容睡眠差异是另一项睡眠评估维度。通过记录了8天睡眠情况的日记,该研究检查了II型糖尿病老年患者的个体内部睡眠变异是否与血糖控制有关。该样本对象在工作日和周末的睡眠方式相似。较大的个体内部睡眠差异和平均睡眠时间与血糖控制较差有着独立关联。建议糖尿病患者保持规律的睡眠。.

Background Brassica napus L. has little or no primary dormancy, but exhibits great variation in secondary dormancy. Secondary dormancy potential in oilseed rape can lead to the emergence of volunteer plants that cause genetic contamination, reduced quality and biosafety issues. However, the mechanisms underlying secondary dormancy are poorly understood. In this study, cultivars Huaiyou-WSD-H2 (H) and Huaiyou-SSD-V1 (V), which exhibit low (approximately 5%) and high (approximately 95%) secondary dormancy rate, respectively, were identified. Four samples, before (Hb and Vb) and after (Ha and Va) secondary dormancy induction by polyethylene glycol (PEG), were collected to identify the candidate genes involved in secondary dormancy via comparative transcriptome profile analysis. Results A total of 998 differentially expressed genes (DEGs), which are mainly involved in secondary metabolism, transcriptional regulation, protein modification and signaling pathways, were then detected. Among these DEGs, the expression levels of those involved in the sulfur-rich indole glucosinolate (GLS)-linked auxin biosynthesis pathway were markedly upregulated in the dormant seeds (Va), which were validated by qRT-PCR and subsequently confirmed via detection of altered concentrations of indole-3-acetic acid (IAA), IAA conjugates and precursors. Furthermore, exogenous IAA applications to cultivar H enhanced secondary dormancy. Conclusion This study first (to our knowledge) elucidated that indole GLS-linked auxin biosynthesis is enhanced during secondary dormancy induced by PEG, which provides valuable information concerning secondary dormancy and expands the current understanding of the role of auxin in rapeseed. Electronic supplementary material The online version of this article (10.1186/s12870-019-1866-z) contains supplementary material, which is available to authorized users.