Search

The Cu2+ in the drinking water has a very serious impact on human health and social ecology. Many countries have the policy on the Cu2+ concentration limitation in drinking water and the industrial Cu2+ emission standards for the treated wastewater. Scientists have developed many methods to remove Cu2+ from wastewater. Among all the adsorption method is widely used due to its high efficacy, feasibility and low cost. The adsorbent is critical to achieving superior Cu2+ removal result. In this paper, Fe3O4/carbon-graphene oxide nanocomposites (Fe3O4@C-GO) were prepared by a hydrothermal method. The Fe3O4@C-GO is the main absorbent to Cu2+ through chemisorption. The specific surface area of Fe3O4@C-GO dramatically increases from 16 m2/g of Fe3O4@C to 62 m2/g, which expands the Cu2+ absorption capacity up to 350 mg/g. Fe3O4 nanoparticles with about 12 nm in diameter are uniformly encapsulated in the C-GO matrix, and therefore the Fe3O4@C-GO can be easily separated from the solution via magnetics. This adsorbent is also very easily recovered by an external magnetic field from the treated wastewater and has high reusability.

Due to the poor plasticity of an aluminum alloy at room temperature, it is difficult to form thin-walled and complex curved parts. This paper proposes a composite method of inverse bulge pre-deformation deep-drawing based on intelligent magnetorheological (MR) fluid material. The experiments and FEM modeling of cylindrical parts with drawing ratios of K1 = 2.125 and K2=2.25 were carried out under different forming conditions. The effect of soft mold medium on the drawing forming of cylindrical parts was studied. The research results show that the uniformity of the wall thickness of the parts is enhanced after using the soft mold medium. When the inverse bulge height is about 9mm and 5mm, the wall thickness variance of the cylindrical part is 0.0023 and 0.0025, respectively, which is reduced by 86.31% and 82.8%, respectively. In the pre-deformation stage, as the height of the inverse bulge is increased, the maximum equivalent stress moves from the fillet area of the blank holder to the outer surface of the highest point of the bulging area. Taking a drawing ratio of K1 = 2.125 as an example, the circumferential compressive stress in the flange area decreases and is distributed uniformly under the back pressure and soft draw beads; the radial stress gradient and equivalent stress gradient at the fillet of die are reduced. For cylindrical parts with drawing ratios of K1 = 2.125 and K2 = 2.25, when the inverse bulge height is 9mm and 5mm, the forming effect of the part is the best.

This work describes the investigation of separation performance of the p-tert-butyl(tetradecyloxy)calix[6]arene (C6A-C10-OH) as stationary phase for gas chromatography (GC) separations. Its structure was characterized by IR, 1H NMR, 13C NMR, MS and single-crystal X-ray diffraction analysis. The C6A-C10-OH column shows good separation capacity for aliphatic, aromatic and cis-/trans- isomers. Especially, it exhibits multiple molecular recognition interactions for the analytes with a wide range of polarity, including dispersion, π-π, H-bonding and dipole-dipole interactions. The present work provides experimental and theoretical basis for the designing of the new calixarene stationary phases in GC analyses.

In this paper, we demonstrate a wavelength division multiplexing (WDM) based system for simultaneously delivering ultrastable optical frequency reference, 10 GHz microwave frequency reference, and one pulse per second (1 PPS) time signal via a 50 km fiber network. For each signal, a unique noise cancellation technique is used to maintain the precision of them. After being compensated, the transfer frequency instability in terms of overlapping Allan deviation (OADEV) for the optical frequency achieves 2E-17/s and scales down to 2E-20/10000 s, which for the 10 GHz microwave reference approaches 4E-15/s and decreases to 1.4E-17/10000 s, and the time uncertainty of the 1 PPS time signal along the system is 2.08 ps. In this scheme, specific channels of WDM are respectively occupied for different signals to avoid the possible crosstalk interference effect between the transmitted reference signals. To estimate the performance of the above scheme, independent of these signals is also demonstrated in this 50 km link, the results are similar to that in the case of simultaneous delivery. This work shows that the WDM-based system is a promising method for building a nationwide time and frequency fiber transfer system with a communication optical network., 11 pages,4 figures,1 table

The aim of this study was to determine the effect of bone morphogenetic protein-7 (BMP-7) and ornidazole (ORN) loaded Chitosan/β-glycerophosphate (CS/β-GP) thermosensitive hydrogels on periodontal regeneration. CS/β-GP hydrogels with and without BMP-7 and ORN were compared with respect to physicochemical properties, release kinetics, and antimicrobial activity in vitro, and periodontal regeneration properties in class III furcation defects in beagles via radiography, histology including immunohistochemical staining of osteoblasts and osteoclasts, and histometric analysis. CS/β-GP hydrogels with and without BMP-7 and ORN had comparable physicochemical properties and gelation kinetics. Release kinetics showed that the hydrogels were capable of stable and sustained release of BMP-7 and ORN. The hydrogels loaded with ORN exhibited obvious antimicrobial activity against P. gingivalis. Histometric analysis quantitatively showed significantly more new bone and cementum, and less connective tissue in defects implanted with BMP-7 loaded hydrogels compared with hydrogels without BMP-7. The number of osteoclasts reduced significantly in the CS/BMP-7/ORN and CS/BMP-7 groups, while the number of osteoblasts increased significantly in these groups. Our findings showed that BMP-7 and ORN conferred additional advantages to the CS/β-GP hydrogel in periodontal regeneration and suggest potential consideration of this approach for periodontal therapy.

Highly dense zirconia dental ceramic coatings were fabricated by aqueous electrophoretic deposition (EPD) and subsequently sintered between 1250 and 1450 °C. Microstructural examination revealed that aqueous EPDZrO2 coatings possessed a tetragonal phase structure and the grain size increased with increasing sintering temperature. Nanoindentation study proved that the aqueous EPDZrO2 coating also had excellent mechanical properties. The effect of different applied loads on hardness and elastic modulus of the 1350 °C-sintered sample at room temperature was investigated by the method of progressive multicycle measurement nanoindentation. The simulative experiment proved that hardness of aqueous EPDZrO2 exhibited reverse indentation size effect (ISE) behavior and then displayed the normal ISE response. The analysis indicates that the reverse ISE is attributed to the relaxation of surface stresses resulting from indentation cracks at small loads and normal ISE is caused by geometrically necessary dislocations. The tetragonal—monoclinic stress-induced phase transformation during nanoindentation is the primary cause of dental zirconia failures.

Due to the poor plasticity of aluminum alloy at room temperature, it is difficult to form thin-walled and complex curved parts. This paper proposes a composite method of inverse bulge pre-forming deep drawing based on intelligent magnetorheological (MR) fluid materials. Through the experiments and finite element modeling of cylindrical parts with drawing ratios of K1=2.125 and K2=2.25 were carried out under different forming conditions. The effect of soft mold medium on the drawing forming of cylindrical parts was studied. The research results show that the uniformity of the wall thickness of the parts is enhanced after using the soft mold medium. When the inverse bulge height is about 9mm and 5mm, the wall thickness variance of the cylindrical part is 0.0023 and 0.0025 pectively, which is reduced by 86.31% and 82.8% respectively. In the pre-forming stage, as the height of inverse bulge is increased, the maximum equivalent stress moves from the fillet area of the blank holder to the outer surface of the highest point of the bulging area. Taking drawing ratio of K1=2.125 as an example, the circumferential compressive stress in the flange area decreases and is distributed unifomly under the back pressure and soft drawbeads, the radial stress gradient and equivalent stress gradient at the fillet of die are reduced; For cylindrical parts with drawing ratios of K1=2.125 and K2=2.25, when the inverse bulge height is 9mm and 5mm, the forming effect of the part is the best.

Dalbergia cultrata is a Near Threatened species with high ecological and economic values. In this study, its chloroplast genome was assembled using Illumina pair-end sequencing dataset. The chloroplast genome has a quadripartite structure with 156,385 bp in length and contains a pair of 16,392 bp inverted repeat (IR) regions, which were separated by large single copy (LSC: 86,040 bp) region and small single copy (SSC: 37,561 bp) region. A total of 121 genes were annotated, including 77 protein-coding genes (PCGs), 36 tRNAs, and 8 rRNAs. The overall GC content was 36.1%. The phylogenetic analysis revealed that D. cultrata has close relationship to D. hainanensis and D. odorifera. This complete chloroplast genome can be readily used for population genetic studies of D. cultrata.

We demonstrate the coherent transfer of an ultrastable optical frequency reference over a 490 km noisy field fiber link. The fiber-induced phase noise power spectrum density per-unit-length at 1 Hz offset frequency can reach up to 510 rad2⋅Hz−1⋅km−1, which is much higher than the fiber noise observed in previous reports. This extreme level of phase noise is mainly due to the fiber link laying underground along the highway. Appropriate phase-locked loop parameters are chosen to complete the active compensation of fiber noise by measuring the intensity fluctuation of additional phase noise and designing a homemade digital frequency division phase discriminator with a large phase detection range of 212 π rad. Finally, a noise suppression intensity of approximately 40 dB at 1 Hz is obtained, with fractional frequency instability of 1.1 × 10−14 at 1 s averaging time, and 3.7 × 10−19 at 10000 s. The transfer system will be used for remote atomic clock comparisons and optical frequency distribution over a long-distance communication network established in China.

Although the prevalence of inflammatory bowel disease (IBD) has been increasing worldwide, the etiology remains elusive. Investigating oral microbiota dysbiosis is essential to understanding IBD pathogenesis. Our study evaluated variations in salivary microbiota and identified potential associations with IBD. The saliva microbiota of 22 IBD patients and 8 healthy controls (HCs) was determined using 16S ribosomal RNA (rRNA) gene sequencing and analyzed using QIIME2. A distinct saliva microbiota dysbiosis in IBD, characterized by alterations in microbiota biodiversity and composition, was identified. Saccharibacteria (TM7), Absconditabacteria (SR1), Leptotrichia, Prevotella, Bulleidia, and Atopobium, some of which are oral biofilm-forming bacteria, were significantly increased. Moreover, levels of inflammatory cytokines associated with IBD were elevated and positively correlated with TM7 and SR1. Functional variations include down-regulation of genetic information processing, while up-regulation of carbohydrate metabolism and protein processing in the endoplasmic reticulum in IBD. Our data implicate salivary microbiota dysbiosis involving in IBD pathogenesis.

Wei Wang, Lin Zhang, Yan Xie, Tianchang Zhen, Gongzhang Su, Qi Zang Department of Thoracic Surgery, The Affiliated Qianfoshan Hospital of Shandong University, Jinan, China Abstract: Targeted therapy is commonly used for treating advanced malignant tumors. Compared with cytotoxic drugs, targeted drugs have the characteristics of good curative results, less adverse effects, and convenient oral administration. Hence, they are especially suitable for patients with cancer who are not able to tolerate chemotherapy. Anti-angiogenic therapy can achieve the objective by inhibiting the formation of new blood vessels in tumors. Apatinib is a novel tyrosine kinase inhibitor targeting the intracellular domain of vascular endothelial growth factor receptor-2. It has been proven to be effective and safe in treating patients with gastric carcinoma and gastroesophageal junction carcinoma. So far, no reports are available on the treatment of esophageal cancer with apatinib. Two patients with advanced esophageal cancer were treated with oral apatinib because of their poor physical condition. After treatment, the dyspnea symptoms disappeared and quality of life significantly improved. Chest computed tomography showed massive necrosis of tumor tissues in each patient. The tumors significantly reduced and a cavity was formed locally in each patient. However, both patients died of massive hemoptysis, probably due to the rupture of the bronchial artery eroded by tumors. The results indicated that apatinib was effective in treating some patients with advanced esophageal cancer, and adverse effects were controllable. However, doctors should choose appropriate candidates according to apatinib’s indications. In addition, the use of apatinib should be carefully controlled for patients with esophageal cancer, especially in those with large vessels and trachea or bronchus eroded by tumor, so as to avoid or reduce the occurrence of fatal hemorrhage. Keywords: angiogenesis inhibitor, esophageal carcinoma, targeted drug, hemoptysis, VEGFR-2

NiO and graphene composite electrode materials, due to their synergistic effects, are gaining increasing attention in the field of energy storage. However, the nucleation mechanism of NiO on graphene is incompletely understood. Here, highly dispersed NiO nanodots with a size of 1.48 nm anchored on reduced graphene oxide (NiO NDs@rGO) were synthesized by a solvothermal method. Density functional theory (DFT) results show that NiO NDs are more easily trapped by the defects on graphene through strong adsorption, which greatly reduces the possibility of diffusion and prevents agglomeration of NiO NDs. As a result, NiO NDs are mainly connected to defects on graphene, which explain the uniform dispersion of NiO NDs on the graphene surface. This unique structure serves to promote ion accessibility and shorten the electron transfer path from redox sites to the graphene backbone. Electrochemical evaluation shows that utilizing the composite as an electrode material for aqueous electrolytes can greatly improve the overall electrochemical performance. The combination of theory and the experimental study provides guidance for the design of new electrode materials.

Lung adenocarcinoma (LAC) is the leading cause of cancer-related death worldwide. Aberrant expression of genes expressed preferentially in the lung tumor vasculature may yield clues for prognosis and treatment. Von Willebrand factor (vWF) is a large multifunctional glycoprotein with a well-known function in hemostasis. However, vWF has been reported to exert an anti-tumor effect, independent of its role in hemostasis. We investigated the expression of vWF in LAC through immunohistochemical staining of tumor tissue microarrays (TMAs). We found that vWF was overexpressed preferentially in the tumor vasculature of LAC compared with the adjacent tissue vasculature. Consistently, elevated vWF expression was found in endothelial cells (ECs) of fresh human LAC tissues and transplanted mouse LAC tissues. To understand the mechanism underlying vWF up-regulation in LAC vessels, we established a co-culture system. In this system, conditioned media (CM) collected from A549 cells increased vWF expression in human umbilical vein endothelial cells (HUVECs), suggesting enhanced expression is regulated by the LAC secretome. Subsequent studies revealed that the transcription factor GATA3, but not ERG, a known regulator of vWF transcription in vascular cells, mediated the vWF elevation. Chromatin immunoprecipitation (ChIP) assays validated that GATA3 binds directly to the +220 GATA binding motif on the human vWF promoter and A549 conditioned media significantly increases the binding of GATA3. Taken together, we demonstrate that vWF expression in ECs of LAC is elevated by the cancer cell-derived secretome through enhanced GATA3-mediated transcription.

The Polycomb group genes are a general class of regulators that are responsible for maintaining homeotic gene expression throughout cell division. Polycomb group expression plays an important role in oncogenesis of several types of human cancer. Melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 are key Polycomb group proteins. Studies have shown that melanoma nuclear protein 18 is a potential tumor suppression, and B-cell-specific Moloney leukemia virus insert site 1 is overexpressed in several human malignancies. However, the roles of melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 in esophageal squamous cell carcinoma are still unclear. In this study, we analyzed the expression levels of melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 in 89 esophageal cancer tissues and paired normal mucosal tissues using immunohistochemistry, Western blotting, and quantitative real-time polymerase chain reaction analyses. We found that the expression of melanoma nuclear protein 18 in the carcinoma tissues was significantly lower than that in the noncancerous mucosal tissues (P < .05), and B-cell-specific Moloney leukemia virus insert site 1 expression in the carcinoma tissues was significantly higher than that in the noncancerous mucosal tissues (P < .05). In addition, the expression of melanoma nuclear protein 18 was correlated with clinical stage, depth of invasion, and lymph node metastasis (P < .05) but was not correlated with gender, age, degree of differentiation, or disease-free survival (P > .05). B-cell-specific Moloney leukemia virus insert site 1 expression was strongly correlated with the degree of differentiation, clinical stage, and lymph node metastasis (P .05). Moreover, there was a negative correlation between melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 expressions in esophageal squamous cell carcinoma (P < .05). Our study suggests that melanoma nuclear protein 18 and B-cell-specific Moloney leukemia virus insert site 1 may play a crucial role in esophageal squamous cell carcinoma. Melanoma nuclear protein 18 or B-cell-specific Moloney leukemia virus insert site 1 may be a potential biomarker for diagnosis and prognosis of esophageal squamous cell carcinoma.

High expression of B-cell specific Moloney leukemia virus insert site 1 (Bmi-1) and peptidyl arginine deiminase IV (PADI4) is associated with esophageal carcinoma. However, few studies have investigated the association between the Bmi-1 and PADI4 genes. The aim of the present study was to evaluate the expression of Bmi-1 and PADI4 and identify the association between the Bmi-1 and PADI4 genes in esophageal squamous cell carcinoma (ESCC) tissues. Bmi-1 and PADI4 gene expression levels were measured using immunohistochemistry, western blotting and reverse transcription-quantitative polymerase chain reaction in ESCC tissues from 86 patients who had not received pre-operative chemoradiation. The results revealed that the Bmi-1 and PADI4 genes had increased expression in carcinoma tissues compared with pericarcinous tissue (P0.05). The expression of PADI4 was associated with clinical stage, depth of invasion and lymph node metastasis (P0.05). In addition, there was a positive association between Bmi-1 and PADI4 gene expression in ESCC (P

We demonstrate the effect of utralstable laser in the high-precision coherent phase transfer of optical frequency. The ultra-stable laser with a linewidth of 0.68 Hz is applied for the optical frequency transfer over a 100 km-fiber link, achieving a transfer instability of 4.9× 10-17 at 100 s, which is about one order of magnitude superior than that with a 2.7 kHz linewidth laser, two times less than that with a 50 Hz linewidth laser. This indicates that the ultrastable lasers will play an important role in the optical frequency transfer.

We report the development of ultrastable lasers at 1.5μm. Through PDH method, the fiber lasers are locked to two ultra-stable optical cavities with finesse of 483000 and 148000 respectively. Through comparing two similar ultrastable laser systems, the linewidth of 0.68Hz and the fractional frequency instability of 2.7×10-15 at 1s averaging time are achieved.

Com o desenvolvimento da globalização, a China e os países lusófonos têm cada vez mais contactos e comunicações ao nível de cultura, política, turismo, economia e especialmente de comércio. Considerando que muitos alunos chineses pretendem ter a Língua Portuguesa como instrumento de trabalho, nomeadamente como tradutores, é crucial que possuam um conhecimento alargado da carga semântica das palavras. Nesse sentido, foram realizados alguns testes para verificar o domínio de algumas palavras polissémicas e entender os motivos para as dificuldades sentidas, de modo a apresentar ideias para as solucionar em contexto de sala de aula. Os dados da investigação conduzida com alunos chineses que frequentam a Universidade de Aveiro mostram que uma grande parte dos alunos chineses que aprendem Português como Língua 2.ª (PL2) têm dificuldades na compreensão das palavras polissémicas em casos específicos. Além disso, desconhecem os significados das palavras polissémicas de uso menos comum ou de baixa referência e revelam problemas para expressar com precisão os significados solicitados em português. Mediante os resultados, sugere se conhecer a cultura portuguesa, formar um pensamento português, alterar a atitude passiva da aprendizagem e procurar métodos adequados e eficazes para melhorar o português. As the development of globalization, China and the Portuguese-speaking countries have more and more contacts and communications at the areas of culture, politics, tourism, economy, especially trade. Considering that many Chinese students intend to have Portuguese as their working language, in particular, those want to be a translator, it is critical that they have a thorough understanding of the semantic knowledge of words. In this sense, it is important to make some tests to verify the mastery of some polysemic words, to understand the motivations for the difficulties they are having and to present some ideas to solve them in the classroom context. The research data from Chinese students attending University of Aveiro show that a large proportion of Chinese students learning Portuguese as Second Language (PL2) have difficulties in understanding polysemic words in specific cases, and their main difficulties are unaware of the meanings of polysemic words of less common or low reference use and lack of ability to accurately express the meanings requested in Portuguese. Conforming the analysis of the results the author provides some solutions of the problems. Through the results, it is suggested to know the Portuguese culture, to form a Portuguese thought, to change the passive attitude of learning, and to seek adequate and effective methods to improve Portuguese. Mestrado em Português Língua Estrangeira/Língua Segunda

A polarization-insensitive recirculating delayed self-heterodyne method (PI-RDSHM) is proposed and demonstrated for the precise measurement of sub-kilohertz laser linewidths. By a unique combination of Faraday rotator mirrors (FRMs) in an interferometer, the polarization-induced fading is effectively reduced without any active polarization control. This passive polarization-insensitive operation is theoretically analyzed and experimentally verified. Benefited from the recirculating mechanism, a series of stable beat spectra with different delay times can be measured simultaneously without changing the length of delay fiber. Based on Voigt profile fitting of high-order beat spectra, the average Lorentzian linewidth of the laser is obtained. The PI-RDSHM has advantages of polarization insensitivity, high resolution, and less statistical error, providing an effective tool for accurate measurement of sub-kilohertz laser linewidth.

We demonstrate a novel polarization control system based on a gradient descent algorithm, applied to a 450-km optical frequency transfer link. The power of the out-loop beat note is retrieved by controlling the polarization state of the transferred signal, with a recovery time of 24 ms, thereby ensuring the long-term evaluation of the fiber link. As a result, data utilization is enhanced from 70% to 99% over a continuous measurement period of ∼12 h. A fractional transfer instability of 7.2 × 10−20 is achieved at an integration time of 10000 s. This work lays the foundation for the comparison of a remote optical clock system via a long-haul optical fiber link.