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Non-contact identification of cattle is the basis for cattle management, insurance claims, and traceability of milk sources and meat products. In order to lower the threshold of deep learning technology in practical application and improve the recognition accuracy, this paper uses the localization and classification paradigm, fills the image and proposes the LKA (Locate Key Area) module, which further improves the identification accuracy of cattle without using any labeling information. To avoid the impact of different collection devices, we use three brands of mobile phones and two cameras to collect data. Due to the fact that CNN features do not have scale invariance, the image is filled as a square, and the filling value is discussed. Finally, (0,0,0) is selected for filling. In order to reduce the labeling of new data, the face, torso, and body of the cattle are first detected, and then automatically trimmed to build a classification dataset. In order to further improve the accuracy of classification, LKA module is proposed. This module locates key areas based on the results of class activation map and uses shallow features for monitoring. Thereby completing fine-grained feature extraction without supervision information. Finally, the features of different parts are adjusted for fusion recognition. Experiments were conducted on the head, torso, and whole of cattle. Based on the ResNet50 network architecture, after filling the image into a square, the recognition accuracy has been improved by 0.30%, 0.21%, and 0.43%, respectively. After further adding LKA modules, the accuracy rates were improved by 0.59%, 0.59%, and 0.45%, respectively. In the fusion experiment, ResNet50_LKA and MobileNetV3_LKA achieves 100% accuracy. Experiments have realized dataset construction and fine-grained feature extraction without labeled information, and achieved high recognition accuracy, proving the effectiveness of our method. [ABSTRACT FROM AUTHOR]

A series of aralkyl diamine derivatives were designed, synthesized, and evaluated for their triple reuptake inhibitory abilities. Compounds 18c (5-HT, NE, DA, IC 50 = 389, 69, 238 nM), 36a (5-HT, NE, DA, IC 50 = 378, 477, 247 nM), and 36d (5-HT, NE, DA, IC 50 = 501, 206, 357 nM) showed in vivo activities in the rat forced swim test at 5, 10, and 20 mg/kg PO. 36a was identified as the most promising candidate in this study. Specifically, 36a exhibited high selectivity for monoamine transporters over a number of CNS-related targets. Furthermore, 36a showed a good pharmacokinetic properties and acceptable safety profile in preclinical studies. [ABSTRACT FROM AUTHOR]

Nucleic acid hybridization plays a critical role in medical diagnostics and nanotechnology, but its selectivity and robustness remain to be improved. Here, focusing on double-stranded nucleic acid-based hybridization, we present a series of related strategies. Above all, two simple strategies for enriching toehold-included double-stranded nucleic acids have been proposed. On this basis, two universal hybridization methods with higher selectivity than typical toehold exchange reaction and a long target detection method using short probes to extend the detectable length range are realized. We also provide a double-stranded nucleic acids-catalyzed cycle amplification reaction to improve sensitivity, which has superior interference resistance and excellent discrimination for single-base mismatches. Besides, double-stranded nucleic acids with forked toeholds are used as essential elements to construct a series of logic gates that can evaluate different input combinations. Given the unique advantages of double-stranded nucleic acids, we expect the current work to advance the application of double-stranded nucleic acid-based hybridization in medical diagnostics and nanotechnology. [Display omitted] • Two methods for enriching double-stranded nucleic acids that possess toeholds. • Two universal hybridization methods and a long targets detection method were provided. • A double-stranded nucleic acids-catalyzed cycle amplification reaction for improving sensitivity. • Double-stranded nucleic acids for robust logic computation. [ABSTRACT FROM AUTHOR]

Predicting water quality data is an important measure for ecological environment protection in watersheds. Aiming at the problem that existing prediction algorithms rarely analyze the characteristics of future changes in water quality indicators, this paper proposes an out-of-sample prediction model for water quality parameters based on the dual-attention mechanism. The model adopts the Encoder-Decoder architecture to realize the prediction of data series, and combines the dual attention of dimension and time step to improve the prediction performance of out-of-sample data. The model is used to predict the water quality parameters of a multi-parameter river, analyze the trend of the out-of-sample data, and compare the prediction results with the traditional LSTM network and Encoder-Decoder LSTM network, the prediction accuracies of the water quality indicators are improved, and the prediction accuracy of the out-of-sample data of the water quality indicators reaches 80%. This will be of great significance to the comprehensive management of river waters and the high-quality development of ecological environment. • The model achieved out-of-sample prediction of water quality parameters and analyzed the future trend of the data. • Seq2Seq codec structure has been adopted to improve out-of-sample prediction performance. • A dual-attention mechanism has been created to assign weights in both time step and dimension simultaneously. [ABSTRACT FROM AUTHOR]

Highlights: [•] To detect object from complex background, illumination variations and texture. [•] Object recognition from mobile device that utilizes texture and color features. [•] A simple victor distance matching classifier. [•] The proposed method would adopt the few characteristic value. [•] Euclidean distance is also used to represent object similarity. [Copyright &y& Elsevier]

• Novel bio-based poly (aryl ether ketone) from FDCA and guaiacal with the highest biomass content. • The optimum conditions for the reaction using orthogonal experiments. • Excellent thermal properties, mechanical properties, thermoforming solution processablity. • Study of mechanism of polymerization by analyzing the molecular simulations and the properties of the resins. To reduce the dependence on non-renewable resources and to address environmental issues, bio-based high-performance poly(aryl ether ketone), PGFEKK, is prepared using two bio-based monomers derived from guaiacol and 2,5-furandicarboxylic acid. With a biomass content of 64.9%, it is the highest biomass content for poly(aryl ether ketone)s reported to date. In this report, the reaction of the bio-based monomers 6-(4-hydroxy-3-methoxyphenyl) pyridazin-3(2H)-one (GSPZ) and furan-2,5-diylbis((4-fluorophenyl)methanone) (BFBF) is carried out via base-catalyzed nucleophilic substitution. The optimum conditions for the reaction are studied using orthogonal experiments and PGFEKK is obtained with a molecular weight up to 21.5 kg/mol, a glass transition temperature of 212 °C, a 10% weight loss temperature of 452 °C, and a tensile strength of 84 MPa. In addition, PGFEKK has a melt viscosity of only 207 MPa at 329 °C and dissolves in most solvents at room temperature. Such a high-performance bio-based poly(aryl ether ketone) has never been reported before. Furthermore, to study the mechanism of how two bio-based monomers affected the polymerization process and material properties, three other polymers are prepared using two petroleum-based monomers, DHPZ and BFBB, instead of GSPZ and BFBF, by analyzing the molecular simulations and the properties of the materials. [ABSTRACT FROM AUTHOR]

Abstract: Polo-like kinase 1 (PLK1), a variety of serine/threonine-protein kinase, has been reported to play important roles in malignant transformation. The purpose of this study was to investigate the clinicopathological significance of PLK1 expression in malignant glioma. A semi-quantitative RT-PCR assay was performed to detect the expression of PLK1 mRNA in 68 cases of glioma tissues and corresponding non-cancerous brain tissues. Additionally, the correlation of PLK1 mRNA expression with clinicopathological factors or prognosis of glioma patients was statistically analyzed. Multivariate analysis of prognostic factors was performed using the Cox proportional hazard model. Small interfering RNA was used to knockdown PLK1 expression in a glioma cell line and analyze the effects of PLK1 inhibition on growth, cell cycle, apoptosis and chemo- or radiosensitivity of glioma cells. Results showed that the expression of PLK1 mRNA was significantly higher in glioma tissues than in corresponding normal brain tissues. The expression of PLK1 mRNA was closely correlated with WHO grade, KPS and tumor recurrence of glioma patients (P =0.022, 0.030 and 0.041, respectively). Meanwhile, the disease-free and overall survival rates of patients with high PLK1 mRNA expression were obviously lower than those of patients with low PLK1 mRNA expression. Multivariate analysis showed that high PLK1 mRNA expression was a poor prognostic factor for glioma patients (P =0.028). The expression of PLK1 mRNA and protein was significantly down-regulated in stably transfected U251-S cells. PLK1 down-regulation could inhibit growth, induce cell arrest in G2/M phase of cell cycle and apoptosis enhancement in glioma cells. Further, PLK1 down-regulation could enhance the sensitivity of glioma cells to cisplatin or irradiation. Thus, the status of PLK1 mRNA expression might be an independent prognostic factor for glioma patients and targeting PLK1 could be a novel strategy for chemo- or radiosensitization of human malignant gliomas. [Copyright &y& Elsevier]

Abstract: Acrylate polymer/silica nanocomposite particles were prepared through miniemulsion polymerization by using methyl methacrylate/butyl acrylate mixture containing the well-dispersed nano-sized silica particles coupling treated with 3-(trimethoxysilyl)propyl methacrylate (MPS). The encapsulation efficiency of silica particles was determined through the elution and hydrofluoride acid etching experiments, and the size distribution and the morphology of the composite latex particles were characterized by dynamic light scattering and transmission electron microscopy. The coupling treatment of silica with MPS can improve the encapsulation efficiency of silica and the degree of grafting of polymer onto silica. When 0.10g MPS/g silica was used to modify silica, the encapsulation efficiency of silica was greater than 95%, and the degree of grafting of acrylate polymer onto silica was about 60%. Although the average size and the size distribution index of the composite latex particles increased as the weight fraction of silica increased, the stable latex containing the ‘guava-like’ composite particles was obtained. The grafting of polymer onto silica particles improved the dispersion of silica particles in the solvents for acrylate polymer and in the polymer matrix. [Copyright &y& Elsevier]

In this study, an ultrasensitive electrochemical miRNA biosensor based on toehold mediated strand displacement reaction circuits (SDRCs) and molecular beacon mediated isothermal circular strand displacement polymerization reaction (ICSDPR) has been proposed. During the SDRCs module, the cascade strand displacement reaction induces the recycling of the target let 7a and generation of a large amount of strand A (SA). The SA recognition opens the hairpin capture probe immobilized on the gold electrode, thus, varying the distance between the redox molecules and electrode surface. The primer mediated ICSDPR is observed to further generate a large amount of SA, thus, leading to a reduction in the signal. Considering these merits, the proposed method is observed to exhibit a log-linear linearity from 10 aM to 100 pM and ultrahigh sensitivity towards let 7a down to 6.2 aM, with a capability of distinguishing the let 7a family members, thereby, providing a new electrochemical route for early cancer screening. Isothermal amplification combined SDRCs and ICSDPR for sensitive and selective let 7a detection. Image 1 • A multiple amplification strategy based on SDRCs and ICSDPR was designed. • The SDRCs and ICSDPR process exhibited good selectivity and amplified the signal efficiently. • The method exhibited high sensitivity with the LOD of 6.2 aM for miRNA let 7a. • The proposed strategy achieved extensive prospect in complex matrix and real samples of cells. [ABSTRACT FROM AUTHOR]

Sensitive and specific miRNA detection is essential for the early cancer diagnosis. In this work, we design a fluorescent microRNA biosensor based on exponential amplification reaction (EXPAR) and nicking endonuclease-powered three-dimensional (3-D) bipedal DNA walkers (BDW). Target microRNA initiates EXPAR with the help of polymerase and nicking endonuclease to generate the large number of BDW in solution. The newly generated BDW can be continuously assembled onto polystyrene microsphere track co-modified with fluorescence-labeled DNA strand. Thus, in the presence of nicking endonuclease, the walking machine is activated to produce enhanced fluorescent signal in the supernatant. Besides, we prove that BDW holds the faster walking speed than single-legged DNA walker (SDW) based on comparative study. Under optimal conditions, the proposed amplification method owns a wide linear range from 10 fM to 5 nM with a detection limit down to 5.2 fM. The reaction time of the assay takes about 70 min. The combination of enzyme-assisted EXPAR in solution and enzyme-powered BDW on particle significantly increases the signal amplification efficiency and improves the detection sensitivity. Therefore, our method has enormous potential for the application of BDW-related biosensors. EXPAR-BDW strategy based on exponential amplification reaction-triggered three-dimensional bipedal DNA walkers. Image 1 • A strategy for detection microRNA was constructed based on exponential amplification reaction and 3-D bipedal DNA walkers. • The proposed assay shows high sensitivity towards target microRNA 21 with a detection limit of 5.2 fM. • This method is simple in nucleic acid design and can be completed in short measurement time. [ABSTRACT FROM AUTHOR]

During the damage and defects related to rolling contact fatigue (RCF), together with wear occurring at the rail surface, the microscopic characteristics of the rail material change with the accumulation of wheel cycles. To find the relationship between rail material characteristics and RCF damage under wheel-rail contact situations, a series of twin-disc rolling-sliding tests, based on real wheel-rail contact situations at a radius of 80 mm rail profile, was established for a heavy-haul railway in China. The microscale characteristics of the rail disc contact surface was researched, including crack, wear, roughness, and hardness of the U75V rail with different load cycles. The results show that the damage mechanism of RCF and wear alternately dominates the rail disc surface at the microscale, taking a certain cycle as a boundary which makes the RCF crack number and wear rate have opposite evolutionary trends. The above factors also affect the wear at the surface rail discs, alternating between fatigue and adhesion. Meanwhile, increasing the surface micro-hardness leads to a decrease in the relative wear rate and an increase in the roughness, length and number of RCF cracks. The plastic deformation layers, including the severely deformed layer (SDL) and the transition layer (TL), almost maintain the same thickness and the dynamic equilibrium increases during the cycles. Two kinds of cracks are initiated and propagated at the rail disc surface, one at the SDL and the other at the junction of SDL and TL. The number of each kind of crack depends on the SDL thickness. • The RCF and wear mechanisms dominated the rail surface alternately by a certain cycle. • Increasing the microhardness makes wear decreasing followed by an increase in roughness and RCF cracks. • The adhesive and fatigue wear happened alternately during the cycles. • The fracture mode of along or through the crystal depends on plastic deformation layer. • The thickness of the severely deformed and transition layers changes on opposite while keeps the entire thickness constant. [ABSTRACT FROM AUTHOR]

This study utilized air quality data on six pollutants (PM 2.5 , PM 10 , O 3 , CO, NO 2 , and SO 2 ) obtained by monitoring for one year (from Jan 1 to Dec 31, 2016) in 338 Chinese cities at or above the prefectural level, and introduced the comprehensive air quality index (CAQI). Specifically, the CAQI was used to measure the comprehensive status of ambient air quality, after which the spatiotemporal distribution of the CAQI and its spatial correlation and clustering were investigated at the month and year levels, respectively. The CAQI values were generally high nationwide, with remarkable spatiotemporal variations. Additionally, cities with higher (or lower) CAQI values were concentrated in north (or south) China, while those with higher CAQI values were also observed in west and east China. The CAQI values exhibited a U-shaped trend from January to December, with the highest values being observed in winter and spring and the lowest during summer. Moreover, particulate matter (PM 2.5 and PM 10 ) is the major pollutant during most of the year, with PM 2.5 being prevalent in east and central-south China and PM 10 in northwest and north China; CAQI values are highly dependent on particulate concentrations. During summer, O 3 becomes a major pollutant and contributes greatly to CAQI, with the highest O 3 being observed in the Bohai Rim, the middle and lower reaches of the Yellow River, and the eastern coast of China. Finally, there was significant spatial autocorrelation and clustering of the CAQI, with spatial hot spots of CAQI being observed in southwest Xinjiang province, where air pollution issues have not received a great deal of attention, as well in Beijing-Tianjin-Hebei (BTH) and its surrounding areas, while cold spots for CAQI are mainly in south and northeast China. [ABSTRACT FROM AUTHOR]

Digestive system cancers account for nearly half of all cancers around the world and have a high mortality rate. Cell culture and animal models represent cornerstones of digestive cancer research. However, their ability to enable cancer precision medicine is limited. Cell culture models cannot retain the genetic and phenotypic heterogeneity of tumors and lack tumor microenvironment (TME). Patient-derived xenograft mouse models are not suitable for immune-oncology research. While humanized mouse models are time- and cost-consuming. Suitable preclinical models, which can facilitate the understanding of mechanisms of tumor progression and develop new therapeutic strategies, are in high demand. This review article summarizes the recent progress on the establishment of TME by using tumor organoid models and microfluidic systems. The main challenges regarding the translation of organoid models from bench to bedside are discussed. The integration of organoids and a microfluidic platform is the emerging trend in drug screening and precision medicine. A future prospective on this field is also provided. [ABSTRACT FROM AUTHOR]

Abstract: Three new 6,7-seco-ent-kauranoids (1–3) were isolated and structures were elucidated from Isodon sculponeatus. Diterpenoids 1–3 possessing multicyclic skeletons formed via oxygen atoms are all unprecedented among ent-kauranes. Compound 1 displayed significant cytotoxic activity against K562, A549, and HepG2 human tumor cell lines, with IC50 values of 1.4, 2.3, and 2.0μM, respectively, equal to the positive control. Plausible pathways for the biosynthesis of 1 and 2 from one related diterpenoid were also postulated. [Copyright &y& Elsevier]

Abstract: Four novel highly oxygenated trinortriterpenoids, sphenalactones A–D (1–4), were isolated from the leaves and stems of Schisandra sphenanthera and their structures were elucidated by extensive analysis of 1D and 2D NMR data. Compounds 1–4 featured a C27 backbone and showed anti-HIV-1 activity with EC50 values in the range of 35.5–89.1μg/mL with low cytotoxicity against C8166 cells (CC50 >200μg/mL). [Copyright &y& Elsevier]

Abstract: ent-Abietane diterpenoids, hebeiabinins A–F (1–5), together with seven known diterpenoids were isolated from leaves of Isodon rubescens var. rubescens. The structures of 1–5 were established on the basis of spectroscopic analyses, including application of 2D NMR spectroscopic techniques. The diterpenoids isolated were evaluated for the cytotoxicity against A549, HT-29, and K562 tumor cells. Compound 5 was the most active with IC50 value of 0.91μM against A549 cells. [Copyright &y& Elsevier]