A copy of this work was available on the public web and has been preserved in the Wayback Machine. The capture dates from 2017; you can also visit the original URL.
The file type is
Osteoarthritis (OA) is a complex process comprised of mechanical load, inflammation, and metabolic factors. It is still unknown that if chondrocytes undergo ferroptosis during OA and if ferroptosis contribute to the progression of OA. In our study, we use Interleukin-1 Beta (IL-1β) to simulate inflammation and ferric ammonium citrate (FAC) to simulate the iron overload in vitro. Also, we used the surgery-induced destabilized medial meniscus (DMM) mouse model to induce OA in vivo. We verifydoi:10.1016/j.jot.2020.09.006 pmid:33376672 pmcid:PMC7750492 fatcat:aq5z4n763nez3oov6u75xtn53a
more »... ptosis by its definition that defined by the Nomenclature Committee on Cell Death with both in vitro and in vivo model. We observed that both IL-1β and FAC induced reactive oxygen species (ROS), and lipid ROS accumulation and ferroptosis related protein expression changes in chondrocytes. Ferrostatin-1, a ferroptosis specific inhibitor, attenuated the cytotoxicity, ROS and lipid-ROS accumulation and ferroptosis related protein expression changes induced by IL-1β and FAC and facilitated the activation of Nrf2 antioxidant system. Moreover, erastin, the most classic inducer of ferroptosis, promoted matrix metalloproteinase 13 (MMP13) expression while inhibited type II collagen (collagen II) expression in chondrocytes. At last, we proved that intraarticular injection of ferrostatin-1 rescued the collagen II expression and attenuated the cartilage degradation and OA progression in mice OA model. In summary, our study firstly proved that chondrocytes underwent ferroptosis under inflammation and iron overload condition. Induction of ferroptosis caused increased MMP13 expression and decreased collagen II expression in chondrocytes. Furthermore, inhibition of ferroptosis, by intraarticular injection of ferrostatin-1, in our case, seems to be a novel and promising option for the prevention of OA. The translation potential of this article is that we first indicated that chondrocyte ferroptosis contribute to the progression of osteoarthritis which provides a novel strategy in the prevention of OA.
Colorectal cancer is one of the most common cancers worldwide with a high incidence rate. Therefore, the molecular basis of colorectal tumorigenesis and evolution must be clarified. Structure-specific recognition protein 1 (SSRP1) is involved in transcriptional regulation, DNA damage repair, and cell cycle regulation and has been confirmed to be highly expressed in various tumor tissues, including colorectal cancer. However, the role of SSRP1 in the development of colorectal cancer remainsdoi:10.7150/ijms.38439 pmid:31839745 pmcid:PMC6909804 fatcat:osikwe3dprcb5bjahrwf62fcnq
more »... ar. Therefore, this study explored the role of SSRP1 in the occurrence and development of colorectal cancer. Using bioinformatics databases, including samples from the Cancer Genome Atlas (TCGA), we confirmed high SSRP1 expression in human colorectal adenocarcinoma tissues. We demonstrated that SSRP1 knockdown via small interfering RNA significantly inhibited the proliferation of colorectal cancer cells and promoted apoptosis through the AKT signaling pathway, suppressing the invasion and migration of colorectal cancer cells in vitro and in vivo. In conclusion, this study demonstrated that SSRP1 silencing influenced the proliferation and apoptosis of colorectal cancer cells via the AKT signaling pathway.
Beam splitters, especially those with tunable split ratios, play significant role in interferometers, spectrometers, and communication systems. To this end, we proposed a polarization-controllable beam splitter based on dielectric metasurface composed of an array of dielectric pillars. The dielectric metasurface presents phase gradients along two orthogonal directions, say, x-and y-axis, with each phase gradient applicable to one of two orthogonal linear polarizations. Due to the orthogonalitydoi:10.1109/jphot.2020.2971113 fatcat:h2v4qsjtxna6pfgvf22ej6krke
more »... f the dual phase gradients in both position and polarization, an elliptically polarized incident beam can be diffracted into two refracted beams, one lies within xoz plane and the other in yoz plane. More importantly, the split ratio of the two refracted beams is continuously tunable by changing the ellipticity of incident beam. Under extreme case, x-or y-polarized incident beam is refracted into one beam, but in different planes for different kind of linear polarization. Besides, the refracted angle of each refracted beam in respective refracted plane can be easily set by adjusting the phase difference of adjacent rows or columns of metasurface. With same method, a polarization-controllable dual-wavelength beam splitter is also achieved on the basis of phase-gradient metasurface. Such a noncoplanar beam splitter with tunable split ratios may play significant role in novel miniature optical devices and systems.
a ( a 辽宁师范大学功能材料化学研究所 大连 116029) ( b 大连理工大学精细化工国家重点实验室 大连 116024) 摘要 开发低温、高活性和良好稳定性的催化剂成为甲醇气相脱水制二甲醚乃至合成气一步法制二甲醚反应的核心. 在氧化铝挤条成型的纳米 HZSM-5 沸石上负载 Keggin 结构 12-磷钨酸制备了复合固体酸催化剂, 通过 FT-IR、 UV-Raman、 31 P MAS-NMR 和 XRD 对所制备的样品进行表征. 以甲醇气相脱水制二甲醚为探针反应的研究结果表明, 在选定的操作条件下连续运转超过 300 h, 甲醇摩尔转化率大于 87%(理论转化率 90.9%), 二甲醚摩尔选择性高于 99.0%, 是目前该反应非常有效的催化剂之一. 关键词 12-磷钨酸; 纳米 HZSM-5 沸石; 甲醇脱水; 二甲醚 Abstract Exploiting the catalysts with higher activity and stability for methanol dehydration at low temperature has become thedoi:10.6023/a13010107 fatcat:636buzvckjfdlfzl6xfwkkjeoy
more »... central part of research dimethyl ether from synthesis gas or methanol. The crystal size of HZSM-5 zeolite is 50~100 nm. The nanocrystalline HZSM-5 zeolite is thought to be an ideal material for the encapsulation of heteropoly acid (HPA) molecules having a Keggin or Dawson structure since they have the intergranular secondary pores. A HPA/nanocrystalline HZSM-5 complex solid acidic catalyst was prepared by an impregnation method and characterized by FT-IR, UV-Raman, XRD and 31 P MAS-NMR. The 12-phosphotungstic acid (HPW) loaded on nanocrystalline HZSM-5 zeolites was prepared by the following steps. The strip (ф 1 mm×2 mm) nanocrystalline HZSM-5 (Si/Al=4.2) catalyst was prepared by the procedure that reported in the literature. 1.00 g HPW was dissolved in 15 mL deionized water. 10.0 g of the strip nanocrystalline HZSM-5 zeolite were added into the solution and steeped the mixture for 12 h. The slurry mixture was calcined at 350 ℃ for 4 h. This catalyst is denoted HPW-HZSM-5. The FT-IR spectroscopy, UV-Raman spectroscopy and 31 P MAS-NMR of HPW-HZSM-5 characterization results show that the Dawson type structure was well preserved after calcination of the catalysts. The reaction was carried out in a continuous flow fixed-bed reactor (diameter 10 mm). Reaction conditions are listed as following: temperature 200 ℃, WHSV=1.6, F RH (methanol flow rate)=0.08 mL/min; F RH (N 2 flow rate)=8.0 mL/min; catalyst 2.05 g; system pressure 0.8 MPa. The composition of the products was analyzed by a GC-8820 gas chromatograph equipped with FID and a GDX-403 (2 m×4 mm). The reaction performance results, including methanol conversion and dimethyl ether selectivity were subsequently calculated. Under steady state conditions, the catalyst shows good stability, and the conversion of methanol maintains above 87.0 mol% (90.9 mol%) during 300 h, it also shows the selectivity (99.0 mol%) of dimethyl ether under the experimental conditions.
This study aimed to develop and test the reliability and validity of a multi-item nurses' presenteeism behaviour questionnaire. Study 1 administered the Nurse Presenteeism Questionnaire (NPQ) to 250 Chinese nurses. Study 2, surveyed 650 nurses with the NPQ, the Sickness Presenteeism Questionnaire, the Stanford Presenteeism Scale, the General Health Questionnaire, and the Emotional Exhaustion Scale using convenience sampling. After item analysis, the subjects were randomly divided into twodoi:10.3389/fpsyg.2021.679801 pmid:34093374 pmcid:PMC8175652 fatcat:6utg2chanrev3hnhepmmb3ruia
more »... to verify the questionnaire structure. Study 1 revealed the nurses' core symptoms when they go to work with illness, and the NPQ with 11 items was developed. Study 2's item analysis revealed that 11 NPQ items had good discrimination (t = 22.67∼36.11, p < 0.01) and high homogeneity. Besides, the scale had good reliability (Cronbach's = 0.93) and external criterion validity (r = 0.24∼0.84, p < 0.01). Thus, the NPQ can be used to measure presenteeism behaviour in nursing.
Tian and Guo  formulated a credibilistic optimization model for a single-product single-period inventory problem with two suppliers. ... Based on credibility measure, Guo  proposed two single-period inventory models, where the uncertain demands were characterized by discrete and continuous possibility distributions, respectively. ...doi:10.1155/2017/2159281 fatcat:fqw6dqzhdbdv3cffztp3pmtena
The gravel packing completion method for horizontal wells has the advantages of maintaining high oil production for a long time, maintaining wellbore stability, and preventing sand production, so it has become the preferred completion method for horizontal wells. At present, this technology still faces the problems of high sand bed height and poor gravel migration. In order to improve the efficiency of gravel packing in horizontal wells, pulsed gravel packing technology for horizontal wells isdoi:10.3390/en14020292 fatcat:tvdrryfvzjhijm2zh4m6qmyube
more »... roposed for the first time. Based on the mechanism of hydraulic pulse, the Eulerian–Eulerian model, k-ε model based on the renormalization group theory (RNG k-ε model), and Fluent are used to simulate the solid-liquid two-phase flow. By optimizing the parameters such as frequency and amplitude of pulse waveform, the optimal pulse waveform of pulsed gravel packing in horizontal wells is determined. The effects of parameters such as sand-carrying fluid displacement, sand-carrying fluid viscosity, sand-carrying ratio, gravel particle size, and string eccentricity on pulsed gravel packing in horizontal wells are studied, and the distribution law of gravel migration velocity and volume fraction in horizontal wells is obtained. According to the results, it can be seen that with the increase of displacement and viscosity of carrier fluid, the volume fraction of fixed bed and moving bed decreases gradually, while that of suspension bed increases gradually. With the increase of sand-carrying ratio, gravel particle size, and string eccentricity, the volume fraction of fixed bed and moving bed increases gradually, while that of suspended bed decreases gradually. Comparing the effects of conventional gravel packing and pulsed gravel packing in horizontal wells, it can be concluded that the efficiency of pulsed gravel packing in horizontal wells is higher. The volume fraction of fixed bed and moving bed decreased by 30% and 40% respectively, while the volume fraction of suspended bed increased by 20%. The migration velocity of moving bed and suspended bed increased by 40% and 25%, respectively, and the migration ability of gravel improved obviously.
, Shengnan Guo; visualization, Shengnan Guo; writing-original draft, Shengnan Guo; writing-review and editing, Shengnan Guo. ... , Shengnan Guo; methodology, Shengnan Guo and Jianqiu Xu; project administration, Shengnan Guo and Jianqiu Xu; resources, Jianqiu Xu; software, Jianqiu Xu; supervision, Shengnan Guo and Jianqiu Xu; validation ...doi:10.3390/ijgi10070468 fatcat:mxnhp75vlngdheamj4ec77yp5e
We present the design and performance characterization of a Faraday laser directly lasing on the Rb 1529 nm transition (Rb, 5P 3/2 − 4D 5/2 ) with high stability, narrow spectral linewidth and low cost. This system does not need an additional frequency-stabilized pump laser as a prerequisite to preparing Rb atom from 5S to 5P excited state. Just by using a performance-improved electrodeless discharge lamp-based excited-state Faraday anomalous dispersion optical filter (LESFADOF), we realized adoi:10.1038/s41598-017-09501-w pmid:28827670 pmcid:PMC5566958 fatcat:o2gkytzkwfcxzjyxcgopp3fbyy
more »... eterogeneously Faraday laser with the frequency corresponding to atomic transition, working stably over a range of laser diode (LD) current from 85 mA to 171 mA and the LD temperature from 11 °C to 32 °C, as well as the 24-hour long-term frequency fluctuation range of no more than 600 MHz. Both the laser linewidth and relative intensity noisy (RIN) are measured. The Faraday laser lasing on Rb 1529 nm transition (telecom C-band) can be applied to further research on metrology, microwave photonics and optical communication systems. Besides, since the transitions correspongding to the populated excited-states of alkali atoms within lamp are extraordinarily rich, this scheme can increase the flexibility for choosing proper wavelengths for Faraday laser and greatly expand the coverage of wavelength corresponding to atomic transmission for laser frequency stabilization. Published: xx xx xxxx OPEN www.nature.com/scientificreports/ 2 SCIeNtIfIC RePoRtS | 7: 8995 |
Guo 等 人  提 出 注 意 力 时 空 图 卷 积(attention based spatial- temporal graph convolutional networks， ASTGCN)模 型 ， 同 时 捕 获 交 通 流 量 在 空 间 和 时 间 上 的 动 态 影 响 。 ...doi:10.3778/j.issn.1673-9418.2008093 doaj:7e1dfb04850c49c7820a6d11cb8868ef fatcat:4zanv34afvdr7pe4rkthbkq5rq
Phosphorus (P) is an essential nutrient for plant growth. In recent decades, the application of phosphate (Pi) fertilizers has contributed to significant increases in crop yields all over the world. However, low efficiency of P utilization in crops leads to intensive application of Pi fertilizers, which consequently stimulates environmental pollution and exhaustion of P mineral resources. Therefore, in order to strengthen the sustainable development of agriculture, understandings of moleculardoi:10.3390/cells11040651 pmid:35203302 pmcid:PMC8870294 fatcat:okfzclcqe5dl5er5x4hr273hsa
more »... chanisms underlying P efficiency in plants are required to develop cultivars with high P utilization efficiency. Recently, a plant Pi-signaling network was established through forward and reverse genetic analysis, with the aid of the application of genomics, transcriptomics, proteomics, metabolomics, and ionomics. Among these, proteomics provides a powerful tool to investigate mechanisms underlying plant responses to Pi availability at the protein level. In this review, we summarize the recent progress of proteomic analysis in the identification of differential proteins that play roles in Pi acquisition, translocation, assimilation, and reutilization in plants. These findings could provide insights into molecular mechanisms underlying Pi acquisition and utilization efficiency, and offer new strategies in genetically engineering cultivars with high P utilization efficiency.
published in the following Dove Press journal: OncoTargets and Therapy 12 February 2015 Number of times this article has been viewed submit your manuscript | www.dovepress.com correspondence: Zhanjun guo ...doi:10.2147/ott.s78647 pmid:25709475 pmcid:PMC4334349 fatcat:yu6xaapz7bdfdn3yfd3ehnsiea
Objective: To explore a new predictive model of lymphatic vascular infiltration (LVI) in rectal cancer based on magnetic resonance (MR) and computed tomography (CT). Methods: A retrospective study was conducted on 94 patients with histologically confirmed rectal cancer, they were randomly divided into training cohort (n = 65) and validation cohort (n = 29). All patients underwent MR and CT examination within 2 weeks before treatment. On each slice of the tumor, we delineated the volume ofdoi:10.3389/fonc.2020.00457 pmid:32328460 pmcid:PMC7160379 fatcat:cor5zwach5cezepsoncmu4iglq
more »... st on T2-weighted imaging, diffusion weighted imaging, and enhanced CT images, respectively. A total of 1,188 radiological features were extracted from each patient. Then, we used the student t-test or Mann-Whitney U-test, Spearman's rank correlation and least absolute shrinkage and selection operator (LASSO) algorithm to select the strongest features to establish a single and multimodal logic model for predicting LVI. Receiver operating characteristic (ROC) curves and calibration curves were plotted to determine how well they explored LVI prediction performance in the training and validation cohorts. Results: An optimal multi-mode radiology nomogram for LVI estimation was established, which had significant predictive power in training (AUC, 0.884; 95% CI, 0.803-0.964) and validation (AUC, 0.876; 95% CI, 0.721-1.000). Calibration curve and decision curve analysis showed that the multimodal radiomics model provides greater clinical benefits. Conclusion: Multimodal (MR/CT) radiomics models can serve as an effective visual prognostic tool for predicting LVI in rectal cancer. It demonstrated great potential of preoperative prediction to improve treatment decisions.
Maternally expressed gene 3 (MEG3), a long non-coding RNA (lncRNA), has tumor-suppressor properties and its expression is lost in several human tumors. However, its biological role in esophageal squamous cell carcinoma (ESCC) tumorigenesis is poorly defined. The present study determined the role and methylation status of MEG3 in esophageal cancer cells and ESCC clinical specimens, and further observed the competing endogenous RNA (ceRNA) activity of MEG3 in the pathogenesis and development ofdoi:10.1158/1541-7786.mcr-16-0385 pmid:28539329 fatcat:2xhzmecjvncgblimwiv7yvekqm
more »... CC. Significant downregulation of MEG3 was detected in esophageal cancer cells and ESCC tissues and the expression level of MEG3 was significantly increased in cancer cells after treated with the DNA methyltransferase inhibitor 5-Aza-dC. Upregulation of MEG3 led to the inhibition of proliferation and invasiveness of the cancer cells. The aberrant promoter hypermethylation of MEG3 indicates silencing of its expression. Furthermore, MEG3 acts as a ceRNA to regulate the expression of E-cadherin and FOXO1 by binding hsa-miR-9. Upregulation of miR-9 was detected in esophageal cancer cell lines and ESCC tissues, and miR-9 promoted esophageal cancer cell proliferation and invasion. Finally, downregulation and hypermethylation of MEG3 was associated with ESCC patients' survival. Implications: MEG3 functions as a tumor-suppressive lncRNA and aberrant promoter hypermethylation is critical for MEG3 gene silencing in ESCC. In addition, MEG3 acts as a ceRNA to regulate expression of E-cadherin and FOXO1 by competitively binding miR-9 and may be used as a potential biomarker in predicting ESCC patients' progression and prognosis.
« Previous Showing results 1 — 15 out of 272 results