Search

Traditional agricultural cultivation is labor-intensive and vulnerable to natural climate conditions, such as heavy rainfall and drought. Concerns over food safety have also brought attention to the growth of weeds and the misuse of agricultural chemicals, which can have a serious negative impact on crop growth and safety. We investigated the feasibility of the YoloX model in the field of agricultural weed identification to address the problem of weed handling in growing crops. In order to overcome the effects of climate and environment, we chose a purchased weed model for our study. We used a binocular vision camera for image acquisition and created a database containing 6,000 samples and enhanced the original database of 1,000 samples with data. In order to address the complex background of the weed images, the changing lighting environment of the binocular camera-acquired images, and the noise interference, we performed histogram equalization, image denoising, and background processing on the dataset. These processing measures aim to improve the overall learning efficiency of the model in order to improve the accuracy of deep learning on weeds. Target detection platforms based on the TensorFlow and PyTorch frameworks were established, respectively, and the mainstream target detection models Faster R-CNN and YoloX series target detection models were trained with the same dataset for comparative analysis using the longitudinal comparison method. The results show that the training under the PyTorch framework yields better models than the training under the TensorFlow framework. YoloX-x has higher recognition accuracy, faster recognition speed, and more stable compared to the Faster R-CNN model, with an average recognition rate of 97.07% and an average recognition time of 0.062 s. Moreover, the optimization of YoloX by incorporating an attention-focusing mechanism resulted in an improved accuracy rate with a decrease in recognition time, with an average recognition rate of 97.70% and an average recognition time of 0.029 s. [ABSTRACT FROM AUTHOR]

Substrate‐supported metal–organic frameworks (MOFs) films are desired to realize their potential in practical applications. Herein, a novel substrate‐seeding secondary‐growth strategy is developed to prepare composites of uniform MOFs films on aerogel walls. Briefly, the organic ligand is "pre‐seeded" onto the aerogel walls, and then a small amount of metal‐ion solution is sprayed onto the prepared aerogel. The sprayed solution diffuses along the aerogel walls to form a continuous thin layer, which confines the nucleation reaction, promoting the formation of uniform MOFs films on the aerogel walls. The whole process is simple in operation, highly efficient, and eco‐friendly. The resulting hierarchical MOFs/aerogel composites have abundant accessible active sites and enable excellent mass transfer, which endows the composite with outstanding catalytic activity and stability in both liquid‐phase CO2 cycloaddition and electrochemical oxygen evolution reaction (OER) process. [ABSTRACT FROM AUTHOR]

Owing to significantly prolonged survival, targeted therapy has become standardized recommendation for advanced non-small cell lung cancer patients with mutated driver genes. However, the genetic status of lung cancer patients is dynamic. By dynamically monitoring the evolution of genes status, differential genes and concomitant genes related to progressive disease could be confirmed early, so as to achieve a more accurate and comprehensive insight of the whole process management of targeted therapy for lung cancer patients. Under the guidance of accurate genetic testing results, it is helpful to provide patients with more effective, long-term, and stable individualized targeted therapy. [ABSTRACT FROM AUTHOR]

We describe strand-specific, base-resolution detection of 5-hydroxymethylcytosine (5-hmC) in genomic DNA with single-molecule sensitivity, combining a bioorthogonal, selective chemical labeling method of 5-hmC with single-molecule, real-time (SMRT) DNA sequencing. The chemical labeling not only allows affinity enrichment of 5-hmC-containing DNA fragments but also enhances the kinetic signal of 5-hmC during SMRT sequencing. We applied the approach to sequence 5-hmC in a genomic DNA sample with high confidence. [ABSTRACT FROM AUTHOR]

Soil C, N, and P elements are important components of the forest ecosystem. Studying the influence of exogenous carbon input change on the stoichiometry of the forest soil can reveal the element recycling process and the balanced feedback mechanism of the forest ecosystem. In this study, using the research object of a spruce forest in Tianshan Mountain, the short-term effect of exogenous carbon input on soil C, N, and P in the soil was analyzed through Detritus Input and Removal Treatment (DIRT), and then the interrelationship between soil stoichiometry and other soil physicochemical factors under different treatments was discussed. The results showed that:① the soil C, N, and P contents in most soil layers were the highest double litter (DL) treatment, soil ω (C) by soil depth from shallow to deep was 168.92, 119.88, 103.33, and 64.23 g·kg -1 ; soil ω (N) was 10.60, 9.32, 8.78, and 8.07 g·kg -1 ; soil ω (P) was 0.50, 0.45, 0.37, and 0.36 g·kg -1 ; in the no input (NI) treatment, soil ω (C) by soil depth from shallow to deep was 104.56, 89.24, 48.08, and 43.96 g·kg -1 ; soil ω (N) was 6.83, 2.60, 2.63, and 2.22 g·kg -1 ; soil ω (P) was 0.40, 0.34, 0.32, and 0.22 g·kg -1 ; and a decreased trend was shown with the deepening of the soil layer. Except in the NI treatment, C:N was 0-10 cm and significantly higher than that in other soils ( P <0.05), NL soil C:P at 30-50 cm was significantly higher than that in other soils, and NI soil N:P was 0-10 cm and significantly higher than that in other soils ( P <0.05). ② Microbial carbon, nitrogen, and phosphorus were significantly higher from 0-10 cm than that in other soil layers ( P <0.05). ③ Redundancy analysis results showed that soluble organic carbon and microbial nitrogen at different carbon input levels were important factors affecting the stoichiometric characteristics of soil C, N, and P.

Substrate-supported metal-organic frameworks (MOFs) films are desired to realize their potential in practical applications. Herein, a novel substrate-seeding secondary-growth strategy is developed to prepare composites of uniform MOFs films on aerogel walls. Briefly, the organic ligand is "pre-seeded" onto the aerogel walls, and then a small amount of metal-ion solution is sprayed onto the prepared aerogel. The sprayed solution diffuses along the aerogel walls to form a continuous thin layer, which confines the nucleation reaction, promoting the formation of uniform MOFs films on the aerogel walls. The whole process is simple in operation, highly efficient, and eco-friendly. The resulting hierarchical MOFs/aerogel composites have abundant accessible active sites and enable excellent mass transfer, which endows the composite with outstanding catalytic activity and stability in both liquid-phase CO 2 cycloaddition and electrochemical oxygen evolution reaction (OER) process., (© 2020 Wiley-VCH GmbH.)

Objective: To investigate the clinical characteristics, laboratorial and bone marrow pathological features of primary thrombocytopenia (ET) patients with different mutations of CALR, JAK2 and MPL genes., Methods: The chinical data of 120 cases of ET in Jiangsu provincial people's hospital/ The First Affiliated Hospital of Nanjing Medical University from January 2015 to December 2017 were collected and analyzed, including 76 cases with JAK2 gene mutation, 40 cases with CALR gene mutation, 2 cases with MPL gene mutations, 2 cases without gene mutation., Results: Among the ET patients, compared with the JAK2 gene mutation, CALR gene mutation showed statistically significant deareament of white blood cells and hemoglobin (P=0.001, P=0.01) and the male platelets in CALR group showed significant increament (P=0.04). Fourthermore, the average number of megakaryocytes and its cluster numbers in each hight power field of vision showed statistically significant decreament in CALR group as compared with JAK2 group (P=0.001, P=0.001), and thrombotic events in CALR group were signicantly lower than those in JAK2 group (7.5% vs 18.4%) (P=0.03)., Conclusion: Mutations of CALR, JAK2 have different clinical characteristics and blood pathological changes of Chinese ET patients, and their clinical significance is worth to explore.

Suzuki-Miyaura coupling of unactivated alkenyl carbamates is described to construct polysubstituted olefins. The developed process is also suitable for heteroaromatic and even electron-rich aromatic carbamates.

Diaryl sulfates were successfully applied as one-by-one organo electrophiles in Kumada coupling to construct biaryls with the emission of harmless inorganic salts.

Three kinds of conventional surfactants, namely, two nonionic surfactants [polyethylene glycol (23) lauryl ether (Brij-35) and Triton X-100 (TX-100)], one cationic surfactant [n-tetradecyltrimethyl ammonium bromide (TTAB)], and an anionic surfactant [sodium n-dodecyl sulfate (SDS)}, were mixed into the quaternary ammonium gemini surfactant [C(14)H(29)N(+)(CH(3))(2)](2)(CH(2))(2).2Br(-) (14-2-14) in aqueous solution. The exchange rate constants between 14-2-14 molecules in the mixed micelles and those in the bulk solution were detected using two nuclear magnetic resonance (NMR) methods: one-dimensional (1D) line shape analysis and two-dimensional (2D) exchange spectroscopy (EXSY). The results obtained from these two methods were consistent. Both showed that mixing a nonionic conventional surfactant, either Brij-35 or TX-100, enhanced the exchange process between the 14-2-14 molecules in the mixed micelles and those in the bulk solution. In contrast, the anionic surfactant SDS and the cationic surfactant TTAB slowed the process slightly.

Hooking up: FeCl(2) catalyzes the efficient cross dehydrogenative arylation of substrates having benzylic C-H bonds (see scheme). High regioselectivity was observed during the cross-coupling between compounds containing aromatic C(sp(2))-H bonds and benzylic C(sp(3))-H bonds. This process is proposed to proceed by single-electron-transfer oxidation and Friedel-Crafts alkylation.