Allele frequency analysis of Chinese chestnut (Castanea mollissima) populations using fluorescent simple sequence repeats (SSR) analysis

The aim of this study was to establish a method for allele frequency detection in bulk samples. The abundance of polymerase chain reaction (PCR) products in bulk leaf samples was detected using fluorescent labeled Simple sequence repeat (SSR) primers and an Applied biosystems (AB) automatic DNA analyzer. Compared with the conventional SSR technique based on polyacrylamide gel electrophoresis (PAGE) and silver staining, fluorescent SSR was much more sensitive. A total of 78 alleles, an average of 4.6 alleles per locus, were detected among 17 chestnut populations with the primer CmTCR10 (NED) and a total of 41 alleles, an average of 2.4 alleles per locus, were detected with the primer CmTCR24 (6-FAM). Multiplexing the PCR reaction by combining the primer pairs of CmTCR10 and CmTCR24, using different fluorescent dyes for different primers, showed that the alleles could be discriminated and the sizes of the amplified segments were similar. Furthermore, the exact sizes of the amplified fragments and the abundance of the PCR products were determined by fluorescent SSR. After data analysis with GeneScan software and allele calling and output with Genotyper software, allele frequencies were calculated for equal pooled samples in each population using the FREQS-R module in the R statistical computing language. The results indicate that it is feasible to determine allele frequencies in bulked samples based on the detection of SSR-PCR products. The advantages and additional applications of this method are also discussed. The abundance of the PCR products can be used to determine the allele frequencies in bulk samples of chestnut populations.Keywords: Fluorescent simple sequence repeats (SSR), chestnut population, bulk sampling, allele frequencie

Gate-tunable negative differential conductance in hybrid semiconductor-superconductor devices

Negative differential conductance (NDC) manifests as a significant characteristic of various underlying physics and transport processes in hybrid superconducting devices. In this work, we report the observation of gate-tunable NDC outside the superconducting energy gap on two types of hybrid semiconductor-superconductor devices, i.e., normal metal-superconducting nanowire-normal metal and normal metal-superconducting nanowire-superconductor devices. Specifically, we study the dependence of the NDCs on back-gate voltage and magnetic field. When the back-gate voltage decreases, these NDCs weaken and evolve into positive differential conductance dips; and meanwhile they move away from the superconducting gap towards high bias voltage, and disappear eventually. In addition, with the increase of magnetic field, the NDCs/dips follow the evolution of the superconducting gap, and disappear when the gap closes. We interpret these observations and reach a good agreement by combining the Blonder-Tinkham-Klapwijk (BTK) model and the critical supercurrent effect in the nanowire, which we call the BTK-supercurrent model. Our results provide an in-depth understanding of the tunneling transport in hybrid semiconductor-superconductor devices.Comment: 15+6 pages, 4+6 figure

合唱活动对中老年的健康促进

Objective: Assessment of chorus activity on elderly health promotion in the level of immunity, cardiopulmonary function and mental health. Methods: 3 groups of related data within 68 members in the chorus before training, training for 6 months and 12 months were counted and analyzed by computer analysis software. Compared with 50 cases of the same age group, that was collected at the same period, about data at 3 stages. Results: The average data of three phases of chorus is: immune level (CD4): 662.38, 761.22, 764.15, left ventricular ejection fraction (LVEF): 61.11, 61.13, 62.66, short axial shortening rate (FS): 32.61, 32.88, 33.65, lung function tidal volume (TV):1.06, 1.18, 1.16, forced vital capacity (FVC): 2.76, 2.85, 2.95, 1s forced expiratory volume (FEV1): 2.31, 2.42, 2.55, 1s rate (FEV1/FVC): 83.69, 84.91, 86.44, the chase volume (MVV is): 83.25, 81.11, 81.93, mental health score values 124.44, 125.67, 126.22, in addition to that, the TV, MVV and mental health score (SF - 36) did not change outside, other indicators, including the CD4, LVEF, FS, FVC, FEV and FEV1/FVC all have different degrees of ascension. Among them, the CD4 in training after 6 months improved obviously, little change after 12 months. Cardiac function index: EF and FS were improved after training 12 months. Lung function, FEV1, FVC, FEV1/FVC are ascending after training for 6 months and for 12 months. The average data of three phases)of the other group is: immune level (CD4) : 660.24, 661.85, 661.32, left ventricular ejection fraction (LVEF): 61.33, 61.28, 61.31, short axial shortening rate (FS): 32.55, 32.38, 32.46, lung function tidal volume (TV): 1.16, 1.17, 1.16，forced vital capacity (FVC): 2.74, 2.76, 2.76, 1s forced expiratory volume (FEV1): 2.30, 2.31, 2.30,1s rate (FEV1/FVC): 83.94, 83.69, 83.33, the chase volume (MVV is): 83.35, 82.49, 83.06, mental health score values 125.31, 124.86, 124.93. No changes were found in all measurement data of all 3 stages in the other group. Conclusions: The scientific, reasonable and continued chorus training has different degrees of help for raising the level of immune, improving cardiopulmonary function and raising the level of overall health to elderly.目的  评估合唱活动对中老年人群在机体免疫水平、心肺功能及心理健康等方面的促进作用。方法  运用计算机分析软件，对某中老年合唱团68名成员在合唱训练前（第一阶段）、训练6个月（第二阶段）、训练12个月后（第三阶段）所采集的3组数据进行回顾性同比统计分析，并与同期50例同年龄段人群采集的3阶段数据进行比对。结果  合唱团三阶段3组数据各自平均值的变化如下：机体免疫水平（CD4）：662.38、761.22、764.15；心功能左室射血分数（LVEF）值：61.11、61.13、62.66；短轴缩短率（FS）值：32.61、32.88、33.65；肺功能潮气量（TV）值：1.16、1.18、1.16；用力肺活量（FVC）值：2.76、2.85、2.95，第1秒用力呼气容量（FEV1）值：2.31、2.42、2.55，1s率（FEV1/FVC）值：83.69、84.91、86.44；最大通气量（MVV）值：83.25、81.11、81.93；心理健康评分值124.44、125.67、126.22。该组数据除了TV、MVV和健康调查简表（SF-36）没有变化外，其他指标，包括CD4、LVEF、FS、FVC、FEV1和FEV1/FVC均有不同程度的提升。其中，CD4在训练6月后提升明显，第三阶段变化不大。心功能指标：LVEF和FS则在训练12个月后才有提高。肺功能FVC、FEV1和FEV1/FVC则在训练6个月、12个月两个阶段均有提升。非合唱组3阶段3组数据各自平均值的变化如下：CD4：660.24、661.85、661.32；LVEF：61.33、61.28、61.31；FS：32.55、32.38、32.46；TV：1.16、1.17、1.16；FVC：2.74、2.76、2.76；FEV1：2.30、2.31、2.30；FEV1/FVC：83.94、83.69、83.33；MVV：83.35、82.49、83.06；心理健康评分值125.31、124.86、124.93。该组所有测数据3阶段比对均无明显变化。结论  科学、合理、持续的合唱训练，对中老年免疫水平的提高、心肺功能的改善和整体健康水平的提高有着不同程度的帮助

Observation of first-order quantum phase transitions and ferromagnetism in twisted double bilayer graphene

Twisted graphene multilayers are highly tunable flatband systems for developing new phases of matter. Thus far, while orbital ferromagnetism has been observed in valley polarized phases, the long-range orders of other correlated phases as well as the quantum phase transitions between different orders mostly remain unknown. Here, we report an observation of Coulomb interaction driven first-order quantum phase transitions and ferromagnetism in twisted double bilayer graphene (TDBG). At zero magnetic field, the transitions are revealed in a series of step-like abrupt resistance jumps with prominent hysteresis loop when either the displacement field (D) or the carrier density (n) is tuned across symmetry-breaking boundary near half filling, indicating a formation of ordered domains. It is worth noting that the good turnability and switching of these states gives a rise to a memory performance with a large on/off ratio. Moreover, when both spin and valley play the roles at finite magnetic field, we observe abundant first-order quantum phase transitions among normal metallic states from charge neutral point, orbital ferromagnetic states from quarter filling, and spin-polarized states from half filling. We interpret these first-order phase transitions in the picture of phase separations and spin domain percolations driven by multi-field tunable Coulomb interactions, in agreement with Lifshitz transition from Hartree-Fock calculations. The observed multi-filed tunable domain structure and its hysteresis resembles the characteristics of multiferroics, revealing intriguing magnetoelectric properties. Our result enriches the correlated phase diagram in TDBG for discovering novel exotic phases and quantum phase transitions, and it would benefit other twisted moir\'e systems as well

TNF-α Promotes Nuclear Enrichment of TonEBP/NFAT5 to Selectively Control Inflammatory but not Osmoregulatory Responses in Nucleus Pulposus Cells.

Intervertebral disc degeneration (IDD) causes chronic back pain and is linked to production of proinflammatory molecules by nucleus pulposus (NP) and other disc cells. Activation of TonicityResponsive Enhancer-Binding Protein (TonEBP)/NFAT5 by non-osmotic stimuli, including pro-inflammatory molecules, occurs in cells involved in immune response. However, whether inflammatory stimuli activate TonEBP in NP cells and if TonEBP controls inflammation during IDD is unknown. We show that TNF-α, but not IL-1β or LPS, promoted nuclear enrichment of TonEBP protein. However, TNF-α-mediated activation of TonEBP did not cause induction of osmo-regulatory genes. RNA-sequencing showed that 8.5% of TNF-α transcriptional responses were TonEBP-dependent and identified genes regulated by both TNF-α and TonEBP. These genes were over-enriched in pathways and diseases related to Inflammatory Response and Inhibition of Matrix Metalloproteases. Based on RNA-seq results, we further investigated regulation of novel TonEBP targets CXCL1, CXCL2, and CXCL3. TonEBP acted synergistically with TNF-α and LPS to induce CXCL1 proximal promoter activity. Interestingly, this regulation required a highly conserved NF-κB binding site but not a predicted TonE, suggesting crosstalk between these two members of the Rel family. Finally, analysis of human NP tissue showed that TonEBP expression correlated with canonical osmo-regulatory targets TauT/SLC6A6, SMIT/SLC5A3, and AR/AKR1B1, supporting in vitro findings that the inflammatory milieu during IDD does not interfere with TonEBP osmoregulation. In summary, while TonEBP participates in the pro-inflammatory response to TNF-α, therapeutic strategies targeting this transcription factor for treatment of disc disease must spare osmo-protective, pro-survival, and matrix homeostatic activities. [Abstract copyright: Copyright © 2017, The American Society for Biochemistry and Molecular Biology.

Initial Growth of Single-Crystalline Nanowires: From 3D Nucleation to 2D Growth

The initial growth stage of the single-crystalline Sb and Co nanowires with preferential orientation was studied, which were synthesized in porous anodic alumina membranes by the pulsed electrodeposition technique. It was revealed that the initial growth of the nanowires is a three-dimensional nucleation process, and then gradually transforms to two-dimensional growth via progressive nucleation mechanism, which resulting in a structure transition from polycrystalline to single crystalline. The competition among the nuclei inside the nanoscaled-confined channel and the growth kinetics is responsible for the structure transition of the initial grown nanowires

Development of Mural Cells: From In Vivo Understanding to In Vitro Recapitulation

Mural cells are indispensable for the development and maintenance of healthy mature vasculature, valuable for vascular therapies and as developmental models. However, their functional plasticity, developmental diversity, and multitude of differentiation pathways complicate in vitro generation. Fortunately, there is a vast pool of untapped knowledge from in vivo studies that can guide in vitro engineering. This review highlights the in vivo genesis of mural cells from progenitor populations to recruitment pathways to maturation and identity with an emphasis on how this knowledge is applicable to in vitro models of stem cell differentiation

The Red Queen and the seed bank: pathogen resistance of ex situ and in situ conserved barley

Plant geneticists have proposed that the dynamic conservation of crop plants in farm environments (in situ conservation) is complementary to static conservation in seed banks (ex situ conservation) because it may help to ensure adaptation to changing conditions. Here, we test whether collections of a traditional variety of Moroccan barley (Hordeum vulgare ssp. vulgare) conserved ex situ showed differences in qualitative and quantitative resistance to the endemic fungal pathogen, Blumeria graminis f.sp. hordei, compared to collections that were continuously cultivated in situ. In detached-leaf assays for qualitative resistance, there were some significant differences between in situ and ex situ conserved collections from the same localities. Some ex situ conserved collections showed lower resistance levels, while others showed higher resistance levels than their in situ conserved counterparts. In field trials for quantitative resistance, similar results were observed, with the highest resistance observed in situ. Overall, this study identifies some cases where the Red Queen appears to drive the evolution of increased resistance in situ. However, in situ conservation does not always result in improved adaptation to pathogen virulence, suggesting a more complex evolutionary scenario, consistent with several published examples of plant–pathogen co-evolution in wild systems

Parametric Study on Dimensional Control of ZnO Nanowalls and Nanowires by Electrochemical Deposition

A simple electrochemical deposition technique is used to synthesize both two-dimensional (nanowall) and one-dimensional (nanowire) ZnO nanostructures on indium-tin-oxide-coated glass substrates at 70°C. By fine-tuning the deposition conditions, particularly the initial Zn(NO3)2·6H2O electrolyte concentration, the mean ledge thickness of the nanowalls (50–100 nm) and the average diameter of the nanowires (50–120 nm) can be easily varied. The KCl supporting electrolyte used in the electrodeposition also has a pronounced effect on the formation of the nanowalls, due to the adsorption of Cl− ions on the preferred (0001) growth plane of ZnO and thereby redirecting growth on the (100) and (20) planes. Furthermore, evolution from the formation of ZnO nanowalls to formation of nanowires is observed as the KCl concentration is reduced in the electrolyte. The crystalline properties and growth directions of the as-synthesized ZnO nanostructures are studied in details by glancing-incidence X-ray diffraction and transmission electron microscopy