We investigate how the random long-range interactions affect the synchronization features in networks of inertial ratchets,where each ratchet is driven by a periodic time-dependent external force,under the influence of an asymmetric periodic potential.It is found that for a given coupling strength𝐶,the synchronization of the coupled ratchets is induced as the fraction of random long-range interactions𝑝increases and the ratchet networks reach full synchronization for a larger𝑝.It is also found that the system reaches synchronization more effectively for a stronger coupling strength.
Schwann cells play a critical role in peripheral nerve regeneration through dedifferentiation and proliferation. In a previous study, we performed microarray analysis of the sciatic nerve after injury. Accordingly, we predicted that long non-coding RNA NONMMUG014387 may promote Schwann cell proliferation after peripheral nerve injury, as bioinformatic analysis revealed that the target gene of NONMMUG014387 was collagen triple helix repeat containing 1（Cthrc1）. Cthrc1 may promote cell proliferation in a variety of cells by activating Wnt/PCP signaling. Nonetheless, bioinformatic analysis still needs to be verified by biological experiment. In this study, the candidate long non-coding RNA, NONMMUG014387, was overexpressed in mouse Schwann cells by recombinant adenovirus transfection. Plasmid p HBAd-MCMV-GFP-NONMMUG014387 and p HBAd-MCMV-GFP were transfected into Schwann cells. Schwann cells were divided into three groups： control（Schwann cells without intervention）, Ad-GFP（Schwann cells with GFP overexpression）, and Ad-NONMMUGO148387（Schwann cells with GFP and NONMMUGO148387 overexpression）. Cell Counting Kit-8 assay was used to evaluate proliferative capability of mouse Schwann cells after NONMMUG014387 overexpression. Polymerase chain reaction and western blot assay were performed to investigate target genes and downstream pathways of NONMMUG014387. Cell proliferation was significantly increased in Schwann cells overexpressing lnc RNA NONMMUG014387 compared with the other two groups. Further, compared with the control group, m RNA and protein levels of Cthrc1, Wnt5 a, ROR2, Rho A, Rac1, JNK, and ROCK were visibly up-regulated in the Ad-NONMMUGO148387 group. Our findings confirm that long non-coding RNA NONMMUG014387 can promote proliferation of Schwann cells surrounding the injury site through targeting Cthrc1 and activating the Wnt/PCP pathway.
Bin PanZhong-ju ShiJia-yin YanJia-he LiShi-qing Feng
Background Low-density lipoprotein （LDL） receptor is normally regulated via a feedback system that is dependent on intracellular cholesterol levels. We have demonstrated that cytokines disrupt cholesterol-mediated LDL receptor feedback regulation causing intracellular accumulation of unmodified LDL in peripheral cells. Liver is the central organ for lipid homeostasis. The aim of this study was to investigate the regulation of cholesterol exogenous uptake via LDL receptor and its underlying mechanisms in human hepatic cell line （HepG2） cells under physiological and inflammatory conditions. Methods Intracellular total cholesterol （TC）, free cholesterol （FC） and cholesterol ester （CE） were measured by an enzymic assay. Oil Red O staining was used to visualize lipid droplet accumulation in cells. Total cellular RNA was isolated from cells for detecting LDL receptor, sterol regulatory element binding protein （SREBP）-2 and SREBP cleavage-activating protein （SCAP） mRNA levels using real-time quantitative PCR. LDL receptor and SREBP-2 protein expression were examined by Western blotting. Confocal microscopy was used to investigate the translocation of SCAP-SREBP complex from the endoplasmic reticulum （ER） to the Golgi by dual staining with anti-human SCAP and anti-Golgin antibodies. Results LDL loading increased intracellular cholesterol level, thereby reduced LDL receptor mRNA and protein expression in HepG2 cells under physiological conditions. However, interleukin 1β （IL-1β） further increased intracellular cholesterol level in the presence of LDL by increasing both LDL receptor mRNA and protein expression in HepG2. LDL also reduced the SREBP and SCAP mRNA level under physiological conditions. Exposure to IL-1β caused over-expression of SREBP-2 and also disrupted normal distribution of SCAP-SREBP complex in HepG2 by enhancing translocation of SCAP-SREBP from the ER to the Golgi despite a high concentration of LDL in the culture medium. Conclusions IL-1β disrupts cholesterol-media
CHEN Ya-xiRUAN Xiong-zhongHUANG Ai-longLI QiuJohn F. MoorheadZac Varghese
Dynamic recrystallization （DRX） behaviors of a heat-resistant martensitic stainless steel 403Nb during hot deformation have been investigated by single-pass thermo-mechanical simulative experiment at temperatures of 900-1150℃ and strain rates of 0.01-1 s-1 The results show that the true stress-true strain curves of this alloy can be classified into two types, one is of dynamic recovery and the other is of dynamic recrystallization. The DRX in 403Nb alloy is easy to occur at strain rates lower than 0.5 s-1 and deformation temperatures higher than 1000℃. Using regression analysis, the stress multiplier （a） and apparent stress exponent （n） were calculated to be 0.0153 and 3.22, respectively, while the activation energy （Qd） for DRX of 403Nb was calculated to be 367.293 kJ/mol. The constitutive equation of peak stress for DRX was also obtained. Based on P-J method, the critical strain for DRX was accurately determined. The mathematical models of peak strain and kinetic equation for DRX of 403Nb steel were finally established.
Based on the exploratory spatial data analysis （ESDA） technique and geographic information system （GIS） platform, with statistic data of counties in 2005, this paper confirms that there is a large population density gap between counties in 2005 because the Gini coefficient is 0.55. Population distribution does not change a lot during the past decades, and the southeast China is still much more densely populated than the northwest China. The global spa- tial autoeorrelation of population distribution is obvious because Moran＇s I scores 0.42 and local spatial autocorrelation is partly significant. Climate and elevation are still the main natural influ- encing factors. Meanwhile industrial structure and transportation significantly influence population distribution. Different combinations of natural factors have different effects on population distribution. For a long term, climate and terrain factor stability affect population distribution. But its influence will be weakened by progress of technology. Economic development is the main factor that changes population distribution for a short term.
Cucumis hystrix Chakr.(2n=2x=24)is a wild species that can hybridize with cultivated cucumber(C.sativus L.,2n=2x=14),a globally important vegetable crop.However,cucumber breeding is hindered by its narrow genetic base.Therefore,introgression from C.hystrix has been anticipated to bring a breakthrough in cucumber improvement.Here,we report the chromosome-scale assembly of C.hystrix genome(289 Mb).Scaffold N50 reached 14.1 Mb.Over 90%of the sequences were anchored onto 12 chromosomes.A total of 23,864 genes were annotated using a hybrid method.Further,we conducted a comprehensive comparative genomic analysis of cucumber,C.hystrix,and melon(C.melo L.,2n=2x=24).Whole-genome comparisons revealed that C.hystrix is phylogenetically closer to cucumber than to melon,providing a molecular basis for the success of its hybridization with cucumber.Moreover,expanded gene families of C.hystrix were significantly enriched in“defense response,”and C.hystrix harbored 104 nucleotide-binding site-encoding disease resistance gene analogs.Furthermore,121 genes were positively selected,and 12(9.9%)of these were involved in responses to biotic stimuli,which might explain the high disease resistance of C.hystrix.The alignment of whole C.hystrix genome with cucumber genome and self-alignment revealed 45,417 chromosome-specific sequences evenly distributed on C.hystrix chromosomes.Finally,we developed four cucumber-C.hystrix alien addition lines and identified the exact introgressed chromosome using molecular and cytological methods.The assembled C.hystrix genome can serve as a valuable resource for studies on Cucumis evolution and interspecific introgression breeding of cucumber.
Carbon emission is inevitable,and changes with energy consumption and economic development,presents policy options toward sustainable development path.Currently,there is little assurance from policymakers in committing to climate change pledges:taking the Middle-East and North African(MENA)region as a specific case with using 2019 as a cut-off period.We conducted an interim assessment of the Paris Agreement to ascertain whether climate actions are in tandem with emissions reduction targets.Making use of difference-in-difference technique as a quasiexperiment supported by fixed-effects and placebo treatment models,the results point to evidence of less than 1%effective CO_(2) emissions reduction as of 2019 compared to the 2015 level.The current carbon emissions reduction commitment level is far-reaching contrary to the Nationally Determined Contributions(NDCs)pledged(16.43%on average by 2030 compared to the 2015 level).The analysis suggests that achieving NDCs commitments are currently major burden on policymakers since the economic development is highly linked with nonrenewable energy consumption.Furthermore,a more comprehensive framework when accounting for all available renewable and clean energy projects shows reduction levels in the range of 30%-40%from 2020 to 2030.These results suggest that the Paris Agreement in MENA countries may be more effective from 2020,thus underscore the importance of capturing ongoing projects(involving renewable and clean energy technologies)into interim policy assessment.The shared implication is that greater efforts are demanded from the region and at country levels to further decrease emissions through the use of negative emissions technologies particularly in the electricity generation sector.
The AHP-GDM model is used for the assessment of structural stability, with the Bohai Sea area as an exam- ple. In this model, the credit degree of each expert is calculated through the assessment matrix based on the similarity and diversity of vector. The comprehensive opinions of expert panel are quantitatively obtained by considering the effect ofcredit degree. According to the geological structural setting, the Bohai Sea is di- vided into twelve assessment zones of structural stability by non-uniform element method. The structural stability grade of each zone is obtained on the basis of the latest geophysical data, earthquake statistical data, and the information of fault activities, current stress field and crustal deformation. The results show that there are one relatively stable area, three relatively sub-stable areas, six relatively sub-unstable areas and two relatively unstable areas. The assessment results of non-uniform element method are very close with those of uniform grid method with size of 0.25 in longitude direction and 0.14 in latitude direction. However the workload of non-uniform element method is only 1 / 16 of the latter. Compared with traditional assessment methods of structural stability, a more objective and reliable assessment result can be obtained by combining non-uniform element method and AHP-GDM model.
We investigate numerically the influences of Gaussian white noise on the dynamical behaviors of power systems.The studied model is a three-bus system at some specific parameters,and it demonstrates a stable regime that is far from collapse.It is found that with the increasing noise intensityσ,power systems become unstable and fall into oscillations;asσis further increased,noise-induced voltage collapse in power systems takes place.Our results confirm that the presence of noise has a detrimental effect on power system operation.Furthermore,the possible mechanism behind the action of noise is addressed based on a dynamical approach where the bifurcation of the system is analyzed.Our results may provide useful information for avoiding instability problems in power systems.
