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Functional telomeres protect chromosome ends and play important roles in stem cell maintenance and differentiation. Short telomeres negatively impact germ cell development and can contribute to age-associated infertility. Moreover, telomere syndrome resulting from mutations of telomerase or telomere-associated genes exhibits short telomeres and reduced fertility. It remains elusive whether and how telomere lengths affect germ cell specification. We report that functional telomere is required for the coordinated germ cell and somatic cell fate decisions. Using telomerase gene Terc deficient mice as a model, we show that short telomeres restrain germ cell specification of epiblast cells but promote differentiation towards somatic lineage. Short telomeres increase chromatin accessibility to elevate TGFβ and MAPK/ERK signaling for somatic cell differentiation. Notably, elevated Fst expression in TGFβ pathway represses the BMP4-pSmad signaling pathway, thus reducing germ cell formation. Re-elongation of telomeres by targeted knock-in of Terc restores normal chromatin accessibility to suppress TGFβ and MAPK signaling, thereby facilitating germ cell formation. Taken together, our data reveal that functional telomeres are required for germ cell specification by repressing TGFβ and MAPK signaling.

Telomeres, at the ends of chromosomes, protect chromosomes from fusion and preserve genomic stability. However, the molecular mechanisms underlying telomere attrition-induced genome instability remain to be understood. We systematically analyzed the expression of retrotransposons and performed genomic sequencing of different cell and tissue types with telomeres of varying lengths due to telomerase deficiency. We found that critically short telomeres altered retrotransposon activity to promote genomic instability in mouse embryonic stem cells, as evidenced by elevated numbers of single nucleotide variants, indels and copy number variations (CNVs). Transpositions of retrotransposons such as LINE1 resulting from the short telomeres can also be found in these genomes with elevated number of mutations and CNVs. Retrotransposon activation is linked to increased chromatin accessibility, and reduced heterochromatin abundance correlates with short telomeres. Re-elongation of telomeres upon recovery of telomerase partly represses retrotransposons and heterochromatin accumulation. Together, our findings suggest a potential mechanism by which telomeres maintain genomic stability by suppressing chromatin accessibility and retrotransposon activity.

We report the preparation of epoxy-based composites by intercalating low loading of core–shell silicon carbide nanowire-silica-amino (named as SiCnw–SiO2–NH2) hybrids, exhibiting simultaneously high permittivity and thermal conductivity (TC) and maintaining rather low dielectric loss. More interestingly, the epoxy composites with the cobweb-structured SiCnw–SiO2–NH2 hybrids exhibited high thermal conductivity at low filler loading due to space micro-structures and hydrogen bond interaction. Specifically, permittivity of the sample with 3.0 vol% SiCnw–SiO2–NH2 hybrids reaches 61.9 under 0.1 Hz, while its dielectric loss is only 0.012, and possessing a high TC of 1.59 W/m K, respectively.

This study aimed to investigate the correlation of sirtuin2 (SIRT2) with clinical characteristics, prognosis in endometrial cancer (EC) patients, and its effect on chemosensitivity in EC cell lines. A total of 137 EC patients who underwent surgical resection were retrospectively enrolled. SIRT2 expression in tumor tissues (n = 137) and adjacent tissues (n = 61) was detected by immunohistochemistry (IHC) staining and evaluated by a semiquantitative scoring method. EC patients’ clinical characteristics and survival data were collected. Besides, SIRT2 was modulated by plasmid transfection in EC cells, then their chemosensitivity to cisplatin and paclitaxel was evaluated. SIRT2 was increased in tumor tissues compared with adjacent tissues (reflected by both IHC score and high-expression ratio, both P

Co3−xMnxO4 is a bimetal oxide with excellent electrochemical activity in alkaline solution, has been regarded as a promising alternative in the field of ion-air batteries and proton exchange membrane fuel cell (PEMFC). Herein, we report a simple solvothermal-calcination method to fabricate Co3−xMnxO4 with tunable external Co3+/Co2+ and Mn3+/Mn2+ ratio. The tunable ratio of element valence in the bimetal results in a higher exposure of active center for oxygen redox reaction (ORR), and thus lead to a better ORR activity, which was confirmed by X-ray photoelectron spectroscopy characterizations and electrochemical measurements. Specially, Co1.8Mn1.2O4 with a Co3+/Co2+ ratio of 2.08 showed an overpotential of 0.37 V at benchmark ORR current density of 3 mA/cm2 in 0.1 M KOH, which is lower than that of pure oxide (Mn3O4 0.53 V and Co3O4 0.56 V). In addition, the as prepared Co1.8Mn1.2O4 exhibited a positive half-wave potential (0.83 V vs RHE) due to their more active sites, promotes charge transfer, adsorption and desorption of oxygen species. This work provides a strategy for the design and fabrication of earth-abundant, low-cost electrocatalysts for PEMFC in practical applications. Co3−xMnxO4 was fabricated by tuning external Co3+/Co2+ and Mn3+/Mn2+ ratio, and the activity initially shows a positive correlation with the ration of Co3+/Co2+ in Co3−xMnxO4.

To explore the RecET-Cre/loxP system for chromosomal replacement of promoter and its application on enhancement l-leucine production in Corynebacterium glutamicum (C. glutamicum) ATCC14067. The RecET-Cre/loxP system was used to achieve the chromosomal replacement of promoter in C. glutamicum ATCC14067 to adjust the metabolic flux involving the l-leucine synthetic pathway. First, leuAr_13032 from C. glutamicum ATCC13032 which carried two mutations was overexpressed to release enzyme feedback inhibition. Then, comparing different mutations in ilvBNC gene clusters, the results indicated that ilvBNC_CP was most effective to enhance the metabolic flux of pyruvate towards l-leucine synthesis. The promoters of pck, odx and pyk2 were overexpressed under the strong promoter Peftu or Psod to improve the supply of pyruvate. Besides, the promoter PilvBNC was employed to dynamically control the transcription level of icd due to its attenuation mechanism by responding to the concentration of l-leucine. The final engineered strain produced 14.05 g l-leucine/L in flask cultivation. The RecET-Cre/loxP system is effective for gene manipulation in C. glutamicum ATCC14067. Besides, the results demonstrate the potential of C. glutamicum ATCC14067 for l-leucine production and provide new targets and strategies for strain development.

Excessive exposure of glucocorticoids activates adipose lipolysis, increases circulating free fatty acids, and contributes to ectopic lipid deposition in liver and skeletal muscle. Our previous study demonstrated that maternal betaine supplementation attenuates glucocorticoid-induced hepatic lipid accumulation in rat offspring. However, it is unclear whether maternal betaine supplementation is effective in preventing glucocorticoid-induced lipolysis in the adipose tissue of offspring. In this study, 20 pregnant rats were fed with basal or betaine-supplemented (10 g/kg) diets throughout gestation and lactation, and the offspring rats were raised on the basal diet from weaning till 3 months of age followed by daily intraperitoneal injection of saline or 0.1 mg/kg dexamethasone (DEX) for 3 weeks. Chronic DEX treatment significantly (P

The concentration degree of floret flowering date (CDFFD) is an important selection index for earliness breeding of peanut, while the genetic basis of CDFFD-related traits in peanut is poorly understood. The aim of this study was to develop a high-density genetic linkage map of cultivated peanut by combining SLAF-seq (specific locus amplified fragment sequencing) with SSR (simple sequence repeat) techniques and to identify QTL (quantitative trait loci) controlling CDFFD. A RIL population derived from a cross between Silihong and Jinonghei 3 was sequenced by the HiSeq 2500 platform. A total of 1262.02 M high-quality paired-end reads were obtained, and 1,328,966 SNPs (single nucleotide polymorphisms) were developed from parents and progenies, of which 754,499 SNPs were successfully encoded and genotyping. The resulting map consisted of 3326 genetic markers (2996 SNPs and 330 SSRs) distributed in 20 linkage groups (LGs), spanning 1822.83 cM with an average distance of 0.55 cM between adjacent markers. These assigned SNP markers had average sequencing depths of 16.94-, 15.66-, and 20.94-fold in the male parent, female parent, and their progenies, respectively. Based on phenotyping in 4 environments, 15 significant QTL for the CDFFD were identified. And one major QTL for days to accumulation of 25 flowers (DA25F), qDA25F6.2, located on chromosome 6 was obtained, with a phenotypic variance explanation (PVE) of 12.49%. This map exhibited higher resolution and accuracy, which will facilitate more QTL discovery for interested agronomic and quality traits in cultivated peanut.

To explore the conditions ensuring amplitude death is always a topic of research for understanding the nature of real systems. However, the previous studies mainly focus on the coupling, that is, continuous or time-invariant. Here we would bring the discontinuous (on–off) coupling to the coupled nonidentical Stuart–Landau oscillators and Rossler oscillators, respectively. We show that the domains of amplitude death can be effectively enlarged along two directions of coupling strength and parameter mismatch. Specifically, the range of coupling strength is extended infinitely for the appropriate on–off rate and on–off period although it usually is considered to be bounded to induce the amplitude death for continuous coupling. Moreover, our findings are of great importance and have many potential applications for the research of neuroscience and biology where the interaction between the neurons or cells is usually intermittent or discontinuous.

The amplitude death (AD) phenomenon is an important dynamical behavior. Seeking the generation condition that induces AD has been an active and popular research field over the last two decades. In this paper, we report the emergence of AD in the identical coupled system with different network topologies through the pinning control. Using the negative self-feedback as the controllers to pin the network nodes, the critical condition that AD appears can be obtained theoretically. Moreover, the numerical scenarios, such as a single oscillator, two coupled oscillators, and coupled oscillators in regular and complex networks, have also been carried out to validate the effectiveness of the strategy, which coincides with the theoretical predictions. We show that, although the high degree nodes should be pinned preferentially to reach better efficiency for complex networks, the location (or significance) of nodes in network is more noteworthy than the degree of nodes for some regular networks. Our findings therefore provide a possibility to induce AD in coupled systems with different network topologies whose internal parameters and coupling schemes cannot be modified.

Nonlocal coupling, as an important connection topology among nonlinear oscillators, has attracted increasing attention recently with the research boom of chimera states. So far, most previous investigations have focused on nonlocally coupled systems interacted via similar variables. In this work, we report the evolutions of dynamical behaviors in the nonlocally coupled Stuart–Landau oscillators by applying conjugate variables feedback. Through rigorous analysis, we find that the oscillation death (OD) can convert into the amplitude death (AD) via the cluster state with the increasing of coupling range, making the AD regions to be expanded infinitely along two directions of both the natural frequency and the coupling strength. Moreover, the limit cycle oscillation (OS) region and the mixed region of OD and OS will turn to anti-synchronization state through amplitude-mediated chimera. Therefore, the procedure from local coupling to nonlocal one implies indeed the continuous enhancement of coherence among neighboring oscillators in coupled systems.

The amplitude death (AD) phenomenon is found in the relay system in the presence of the mixed couplings composed of attractive coupling and repulsive coupling. The generation mechanism of AD is revealed and shows that the middle oscillator achieving AD is a prerequisite to further suppress oscillation of the outermost oscillators for the paradigmatic Stuart-Landau and Rossler models. Moreover, regarding the Stuart-Landau relay system as a small motif of star network, we also observe that the mixed couplings can facilitate AD state of the whole network system. Particularly, the threshold of coupling strength is invariable with the change of network size. Our findings may shed a new insight to explore the effects of hybrid coupling on complex systems, also provide a new strategy to control dynamic behaviors in engineering science and neuroscience fields.

Rare earth element gadolinium-doped aluminum–zinc oxide (Gd–AZO) semiconductor thin film material was deposited on both silicon and glass substrate by radio frequency (RF) sputtering at room temperature. Electrical properties and microstructure of Gd–AZO thin film were mainly modulated by altering O2 partial pressure (OPP) during the RF sputtering process. Scanning electron microscope (SEM) and X-ray diffraction (XRD) test were carried out to uncover the microstructure variation trend with the sputtering OPP, and amorphous structure which is beneficial to large mass industry manufacture was also demonstrated by the XRD pattern. Transmittance in visible light spectrum implies the potential application for Gd–AZO to be used in transparent material field. Finally, bottom gate, top contact device structure thin film transistors (TFTs) with Gd–AZO thin film as the active channel layer were fabricated to verify the semiconductor availability of Gd–AZO thin film material. Besides, the Gd–AZO TFTs exhibit preferable transfer and output characteristics.

Various aluminum-doped zinc oxide (AZO) films were prepared on Si substrate by atomic layer deposition (ALD) at 100 °C. The effect of the composition of AZO films on their electrical, optical characteristics, structural property and surface topography was investigated. The appearance of electrical resistivity shows their semiconducting properties. In most of the visible light band, all the AZO films present transparency of more than 80 %. Al doping suppresses the AZO film crystallization. When the Al doping concentration increases up to 3.95 at%, the AZO film has some small multicrystal grains with random orientation. Al doping improves the roughness of i-ZnO film. The root mean square (RMS) roughness of samples prepared by ALD is much smaller than that prepared by radio-frequency magnetron sputtering reported.