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Clock genes are essential for the daily functions of vertebrates and invertebrates and participate in a wide variety of biological functions including biochemical, physiological, and behavioral processes. Circadian clock disorders are detrimental to both humans and fish, and therefore research on the regulation of genes involved in the circadian clock has attracted increasing attention. Period 2 (per2) is an important gene whose expression is closely related to melatonin secretion, in addition to being affected by the photoperiod length. To gain more insights into the potential biological function of per2, we have cloned and expressed per2 in Amur minnow (Phoxinus lagowskii). We also analyzed melatonin content and AANAT2 gene expression under different short or long-term photoperiod conditions. In the present study, the secretion of melatonin in P. lagowskii was highest in the dark phase under short-term experiments. In the pituitary, the expression of the per2 gene was highest during the dark phase in both the 16L: 8D and 8L: 16D groups. The expression of the per2 gene in the brain was also highest during the dark phase in the 12L: 12D group. Though the expression of the per2 gene was not the highest in the dark phase for the other groups, there were no significant differences compared to the highest value. In addition, in the brain and pituitary, AANAT2 expression was highest during the light phase, except in the 8L: 16D group. Our findings suggested that Amper2 may participate in the feedback regulation of melatonin by regulating the expression of AANAT2. Fluorescence in situ hybridization analyses confirmed that per2 mRNA was expressed during the dark phase, especially in 16L: 8D group. Immunohistochemistry analyses confirmed that PER2 protein was expressed higher in 8L: 16D group. The dual luciferase experiment first validated the promotion of Wnt/β-Catenin expression by the per2 gene. Our results provide novel insights into the expression and location of per2, which contributes to a better understanding of the role of clock genes in the circadian rhythm and seasonal responses of high-latitude fish and might provide useful information of practical interest for high-latitude aquaculture. [ABSTRACT FROM AUTHOR]

Background: The surgical approach for patients with Siewert type II AEG remains controversial. Several studies have described a new laparoscopic radical resection approach of Siewert type II AEG through the left diaphragm. However, the technical safety and feasibility of the new surgical approach compared with the transhiatal approach have not yet been tested. Study design: We retrospectively reviewed patients with AEG who underwent TSLG and LTH operations in the Guangdong Provincial Hospital of Chinese Medicine between January 2017 and April 2021. Histologically confirmed AEG and D2 lymphadenectomy with curative R0 patients were included, and patients with Siewert I/III AEG or distant metastasis were excluded. Blood loss, the amount of harvested lymph node, and complications related to surgery were evaluated. Results: A total of 99 patients with Siewert type II AEG were analyzed, 44 in the TSLG group and 55 in the LTH group. There was no difference in clinicopathological features between the two groups. The more harvested lymph node (23.33 ± 11.41 vs. 32.18 ± 12.85, p < 0.01), lower mediastinal lymph node (1.07 ± 2.08 vs. 3.25 ± 3.31, p < 0.01), and longer proximal margin length (3.08 ± 1.19 vs. 4.47 ± 0.95 cm, p < 0.01) were observed in the TSLG group. The rate of cure (R0 gastrectomy) in the TSLG group was higher than that in the LTH group (100% vs. 89.09%, p = 0.03). Conclusion: The TSLG approach is associated with improved surgical views, simplified lymphatic dissection in the inferior mediastinum, and more reliable margins. TSLG surgery may be an effective addition to LTH surgery, particularly when lower mediastinal lymph node metastases are suspected. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate the pathogenic factors of glucocorticoids (GCs)-induced osteonecrosis of the femoral head (GONFH) and its underlying pathogenesis in vivo and in vitro. Methods: Radiographical (µCT) scanning, histopathological, immunohistochemical, reactive oxygen species (ROS) and tunel staining were conducted on GONFH patients and rats. ROS, tunel, flow cytometry, alkaline phosphatase, Oil red O staining, reverse transcription‑quantitative PCR and western blotting were applied to elucidate the exact pathogenesis mechanism. Results: Clinical and animal studies demonstrated increased levels of ROS, aggravated oxidative stress (OS) microenvironment, augmented apoptosis and imbalance in osteogenic/lipogenic in the GONFH group compared to the control group. The fate of mesenchymal stem cells (MSCs) directed by GCs is a crucial factor in determining GONFH. In vitro studies further revealed that GCs promote excessive ROS production through the expression of NOX family proteins, leading to a deterioration of the OS microenvironment in MSCs, ultimately resulting in apoptosis and imbalance in osteogenic/lipogenic differentiation. Furthermore, our results confirmed that the NOX inhibitor-diphenyleneiodonium chloride and the NF-κB inhibitor-BAY 11-7082 ameliorated apoptosis and osteogenic/lipogenic differentiation imbalance of MSCs induced by an excess of GCs. Conclusion: We demonstrated for the first time that the aggravation of the OS microenvironment in MSCs caused by high doses of GCs leading to apoptosis and differentiation imbalance is a crucial factor in the pathogenesis of GONFH, mediated through activating the NOX/ROS/NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

Real-time monitoring of the laser paint removal process is critical to realize a good cleaning effect without causing damages to the base. Acoustic signals when the laser pulse continuously acts at one point were studied through an experiment. Results show that peak values and maximum frequency component of acoustic signals decreased to a stable value with paint removal, reflecting the cleaning process. According to an experimental study on cleaning acoustic signals during laser scanning, the cleaning process is divided into paint removal, clean finished, and excessive cleaning according to the damages threshold. The acoustic signals of the different processes were analyzed. Results show that variations of frequency components could reflect the paint removal process more accurately than time-domain signals. Extracting characteristic parameters of the maximum frequency component, spectrum, spectrum centroid amplitude, and spectrum centroid frequency from the frequency domain; introducing in the discriminant analysis; and establishing a Bayesian discriminant model according to cleaning characteristics can realize the quantitative discrimination of the paint removal process. [ABSTRACT FROM AUTHOR]

The generating grinding method has the characteristics of high machining accuracy and high efficiency. Therefore, it is widely used in the finishing process of the face gear tooth surface. The physical performance of the grinding process is an important factor that influences the machining accuracy of the face gear tooth surface. Therefore, to improve the manufacturing accuracy of the face gear, it is necessary to accurately simulate the grinding process of the face gear. Owing to the influence of the complex spatial geometric characteristics of the face gear tooth surface and the grinding wheel, establishing a surface residual modeling method for the face gear is a key challenge in simulating the generating grinding process. To address the aforementioned issues, this study proposes a normal cutting depth iterative method to calculate the grinding residual in the face gear generating grinding process. This method considers the complex 3D spatial characteristics of the face gear tooth surface and establishes the spatial residual model of each node of the face gear surface in the process of generating grinding. Compared with other residual algorithms based on 2D truncation or Boolean operation of face gears, this algorithm has higher computational accuracy and efficiency. Thus, it lays the foundation for accurately establishing the complex spatial microscopic surface topography in the face gear generating grinding process. [ABSTRACT FROM AUTHOR]

The five-axis flank milling process of sculptured surfaces is an intricate process involving time-varying and nonlinear characteristics under the multiphysics coupling effect. The milling force during the process is an important factor that influences the machining accuracy of sculptured surfaces. Face gears, as parts with sculptured surfaces, are widely employed in the aerospace and machinery manufacturing industries. To realize the high-precision manufacturing of face gears with a universal milling machine, this study proposes a five-axis flank milling method for face gears. In addition, based on the tangent plane approximation algorithm and the Receptance Coupling Substructure Analysis (RCSA) method, the milling force and the tool tip vibration during the face gear machining process are investigated. Finally, a five-axis flank milling force model and a face gear surface machining error model are established considering the interaction between the milling force and the process system. [ABSTRACT FROM AUTHOR]

Molybdenum dialkyldithiocarbamate (MoDTC) is widely used as a friction modifier in engine lubricating oil. Under MoDTC lubrication, the friction and wear behaviors of tungsten-doped diamond-like carbon (W-DLC) films annealed at 100–400 °C were discussed and evaluated using scanning electron microscopy (SEM), atomic force microscopy (AFM), and Raman spectroscopy. Under (polymerized alpha olefin) PAO + MoDTC lubrication, the coefficient of friction of all samples decreased, but the wear rates of the W-DLC films annealed at 300 °C increased significantly. By interacting with zinc dialkyldithiophosphate (ZDDP), the wear rates of W-DLC films annealed at different temperatures declined significantly owing to the formation of dense phosphate tribofilms on the worn surfaces. [ABSTRACT FROM AUTHOR]

Polyalphaolefin (PAO) oil is one of the most commonly-used based oil to decrease the fuel energy consumption of mechanical systems, like vehicles. Nevertheless, it heavily relies on environmental toxic organic additives with sulfur, phosphorus, and/or chlorine. Accordingly, nano-carbon materials, such as nano-diamond (ND), onion-like-carbon (OLC) and graphene (Gr.), was adopted to develop a novel kind of environmentally-friendly PAO-based lubricants with low toxic additives. Synergetic effects between nano-carbon materials and MoDTC additives were investigated to enhance friction-reduction and anti-wear performances of PAO oil with molybdenum di-thiocarbamate (MoDTC) additive. Experimental results show that ND and OLC additives are effective in the enhancement of friction-reduction and anti-wear performances of self-mated AISI 52100 steels lubricated under poly-alpha-olefin (PAO) oil with Mo-DTC additive, due to the formation of tribo-film consist of MoSx, polishing, ball-bearing and reinforcement effects of nano-particles. Via the addition of ND or OLC additive with a content of 0.05 wt.%, the optimized dosage of MoDTC additive can be significantly decreased from 1 to 0.1 wt.%. Friction coefficient of self-mated AISI 52100 steels lubricated under PAO oil with 0.1 wt.% Mo-DTC and 0.05 wt.% ND additive is about 0.05, approximately equal to that lubricated under PAO oil with 1 wt.% Mo-DTC additives. Moreover, ND additive resulted in a lower friction coefficient, better wear resistance (about 2.3 × 10− 16 m3/N m) and shorter duration of run-in period than OLC additive in PAO oil with MoDTC additive. Graphene is not helpful to enhance the friction-reduction and anti-wear performance of PAO oil with or without MoDTC, due to the absence of polishing, ball-bearing and reinforcement of nano-particles effects. Although, individual addition of OLC additive in PAO oil also caused friction-reduction effectiveness, serious wear damage occurred attributed to the abrasive of nano-particles. [ABSTRACT FROM AUTHOR]

This study aimed to develop software for multi-axis electrical discharge machining (EDM) computer numerical control (CNC) systems using open CNC technology and soft CNC technology and to then apply the software to the machining of rimmed turbine blisks. Through the analysis of functional requirements, this study established the hierarchy structure of the software. On the basis of this structure, three main modules and their communications were established with Linux and RT-Linux as the development platforms. The software architecture was also constructed. Through the construction of the modules and communications and the realization of the functions, the multi-axis EDM CNC system software was developed and installed into a five-axis EDM CNC machine to realize the machining of rimmed turbine blisks. Machining results show that the architecture of the software is correct, harmonious, and reasonable. The software is also stable and reliable and features strong real-time capability and accurate movement control. [ABSTRACT FROM AUTHOR]

Dense AlO-TiB-BC composites are synthesized by in situ reactive hot press sintering of BC with 20 wt% TiAl and TiAl at 1700 °C, respectively. The sinterability of BC is improved by the intermetallic compounds due to the formation of AlO and TiB. The sizes of AlO, TiB, and BC grains are less than 2.5 μm. The agglomerates of AlO and TiB particles tend to orientationally align in the direction perpendicular to the pressure axis. By incorporation of TiAl, the flexural strength and fracture toughness reach 482 MPa and 3.6 MPa m, respectively. When TiAl is added, the flexural strength is reduced to 408 MPa because of the thermal residual stress, while the fracture toughness is increased to 4.2 MPa·m. The increase of AlO in the composite can reduce the strength and enhance the toughness of the composite due to the thermal residual stress originated from the thermal expansion mismatch between BC and AlO. [ABSTRACT FROM AUTHOR]

Strain NEAU-ST10-9 is a moderately halophilic, coccoid and non-motile bacterium isolated from saline and alkaline soils in the Dechang Township, Zhaodong City, China. The bacterium was found to be aerobic and Gram-stain positive. It forms orange colonies and grows at NaCl concentrations of 2-10 % (w/v) (optimum, 4 % w/v), at 4-50 °C (optimum, 30 °C) and at pH 6.0-10.0 (optimum, pH 7.0). Phylogenetic analyses based on 16S rRNA gene sequences indicated that it belongs to the genus Planococcus within the family Planococcaceae. The most closely related species was Planococcus maritimus, whose type strain (TF-9) showed gene sequence similarities of 99.1 % for 16S rRNA, 83.7 % for gyrB and 87.0 % for rpoB with those of strain NEAU-ST10-9, respectively. DNA-DNA hybridization relatedness values between strain NEAU-ST10-9 and type strains P. maritimus DSM 17275 , P. rifietoensis DSM 15069 , P. plakortidis DSM 23997, P. citreus DSM 20549, P. maitriensis DSM 15305, P. salinarum KCTC 13584 and P. columbae DSM 17517 were from 55 ± 1 to 32 ± 2 %. The DNA G+C content was found to be 45.2 mol %. The major fatty acids (>5 %) were determined as C anteiso, C ω7c alcohol, C ω9c and C anteiso. The major menaquinones of strain NEAU-ST10-9 were identified as MK-7 and MK-8. The polar lipids were found to contain of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphocholine and two unknown lipids. The genotypic, chemotaxonomic and phenotypic analysis indicated that strain NEAU-ST10-9 represents a novel species of the genus Planococcus, for which we proposed the name Planococcus dechangensis sp. nov. The type strain is NEAU-ST10-9 (=CGMCC 1.12151=DSM 25871). [ABSTRACT FROM AUTHOR]

The novel species Halomonas zhaodongensis NEAU-ST10-25 recently identified by our group is a moderate halophile which can grow at the range of 0-2.5 M NaCl (optimum 0.5 M) and pH 6-12 (optimum pH 9). To explore its halo-alkaline tolerant mechanism, genomic DNA was screened from NEAU-ST10-25 in this study for Na(Li)/H antiporter genes by selection in Escherichia coli KNabc lacking three major Na(Li)/H antiporters. One mrp operon could confer tolerance of E. coli KNabc to 0.8 M NaCl and 100 mM LiCl, and an alkaline pH. This operon was previously mainly designated mrp (also mnh, pha or sha) due to its multiple resistance and pH-related activity. Here, we will also use mrp to designate the homolog from H. zhaodongensis (Hz_ mrp). Sequence analysis and protein alignment showed that Hz_ mrp should belong to Group 1 mrp operons. Further phylogenetic analysis reveals that Hz_Mrp system should represent a novel sub-class of Group 1 Mrp systems. This was confirmed by a significant difference in pH-dependent activity profile or the specificity and affinity for the transported monovalent cations between Hz_Mrp system and all the known Mrp systems. Therefore, we propose that Hz_Mrp should be categorized as a novel Group 1 Mrp system. [ABSTRACT FROM AUTHOR]

Background: Clear-cell renal cell carcinoma (ccRCC) is one of the most common types of kidney cancer in adults; however, its causes are not completely understood. The study was designed to filter the key pathways and genes associated with the occurrence or development of ccRCC, acquaint its pathogenesis at gene and pathway level, to provide more theory evidence and targeted therapy for ccRCC. Methods: Gene set enrichment analysis (GSEA) and meta-analysis (Meta) were used to screen the critical pathways and genes which may affect the occurrence and progression of ccRCC on the transcription level. Corresponding pathways of significant genes were obtained with the online website DAVID (). Results: Thirty seven consistent pathways and key genes in these pathways related to ccRCC were obtained with combined GSEA and meta-analysis. These pathways were mainly involved in metabolism, organismal systems, cellular processes and environmental information processing. Conclusion: The gene pathways that we identified could provide insight concerning the development of ccRCC. Further studies are needed to determine the biological function for the positive genes. [ABSTRACT FROM AUTHOR]

A slightly halophilic bacterium (strain NEAU-ST10-25) was isolated from saline-alkaline soils in Zhaodong City, Heilongjiang Province, China. The strain is a Gram-negative, aerobic motile rod. It accumulates poly- β-hydroxyalkanoate and produces exopolysaccharide. It produces beige-yellow colonies. Growth occurs at NaCl concentrations (w/v) of 0-15 % (optimum 3 %), at temperatures of 4-60 °C (optimum 35 °C) and at pH 6-12 (optimum pH 9). Its G+C content is 53.8 mol%. Phylogenetic analyses based on the separate 16S rRNA gene and concatenation of the 16S rRNA, gyrB and rpoD genes indicate that it belongs to the genus Halomonas in the class Gammaproteobacteria. The most phylogenetically related species is Halomonas alkaliphila DSM 16354, with which strain NEAU-ST10-25 showed 16S rRNA, gyrB and rpoD gene sequence similarities of 99.2, 82.3 and 88.2 %, respectively. The results of DNA-DNA hybridization assays showed 60.47 ± 0.69 % DNA relatedness between strain NEAU-ST10-25 and H. alkaliphila DSM 16354, 42.43 ± 0.37 % between strain NEAU-ST10-25 and Halomonas venusta DSM 4743 and 30.62 ± 0.43 % between strain NEAU-ST10-25 and Halomonas hydrothermalis DSM 15725. The major fatty acids are C ω7c (62.3 %), C (17.6 %), C ω7c/C ω6c (7.7 %), C (2.9 %), C 3-OH (2.8 %), C (2.1 %) and C ω9c (1.6 %) and the predominant respiratory quinone is ubiquinone 9 (Q-9). The proposed name is Halomonas zhaodongensis, NEAU-ST10-25 (=CGMCC 1.12286 = DSM 25869) being the type strain. [ABSTRACT FROM AUTHOR]

The advent of microfluidic technologies has enabled a better recapitulation of in vitro tumor model with higher biological relevance over conventional monolayer assays. This work built upon a microfluidic system that supported the spontaneous aggregate formation of tumoral cells under flow-induced dynamic physical forces in a confined microchamber without additional matrix materials. Our findings indicated that fluidic streams significantly modulated the biological and architectural features of human breast adenocarcinoma cell (MCF-7), human hepatocarcinoma cell (HepG2), and human cervix adenocarcinoma cell (HeLa) with cell-type-dependent variation. The microfluidic platform was further integrated with a fluorescence detection and imaging system, allowing for non-invasive monitoring of cellular accumulation and spatial distribution of a chemotherapeutic agent, doxorubicin (DOX). The cytotoxic effects of DOX of various concentrations were determined and compared in MCF-7 cells in conventional two-dimensional (2D) static and microfluidic culture conditions. Dose-dependent response to DOX was noticed in both cultures, whereas tumor micronodules grown in microfluidic devices demonstrated significantly lower sensitivity to DOX at increased concentration. Our platform owns promising potentials as a universal modality for bridging traditional 2D cell cultures and in vivo experimentation for preclinical anticancer drug screening. [ABSTRACT FROM AUTHOR]

The contribution of angiogenesis inhibitor TNP-470 to the growth and metastasis of ACHN renal cell carcinoma (RCC) was studied. TNP-470 (40 mg/kg, every two days) was administrated to BABL/c nude mice bearing ACHN RCC. The mice were sacrificed after a treatment duration of 31 days and the weight and volume of subcutaneous tumors as well as foci of lung metastasis were measured. The microvascular density (MVD) of the tumor as well as the PCNA index and apoptotic index of the tumor cells were evaluated immunohistochemically. Result showed that the growth of ACHN RCC was suppressed significantly and none metastasis was observed in TNP-470-treated mice. Compared with the control group, the MVD was decreased markedly ( P<0.01) and the apoptotic index was increased significantly ( P<0.01) in the treated group. The tumor volume was positively correlated to the MVD ( r=0.7144, P<0.01) and inversely correlated to the apoptotic index ( r=−0.8607, P<0.01), and MVD was conversely correlated to the apoptotic index. It was determined that TNP-470 could effectively inhibit angiogenesis of ACHN RCC, which resulting in ischemia and hypoxia, leading to increased apoptosis, thus obviously suppressing the growth and metastasis of ACHN RCC in nude mice. [ABSTRACT FROM AUTHOR]