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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]

The rational design and exploitation of highly active and stable catalysts for the electrochemical oxidation of biomass-derived 5-hydroxymethylfurfural (HMF) to valuable chemical 2,5-furandicarboxylic acid (FDCA), is of great significance. Herein, a ternary metal–organic framework nanoarray is in situ hydrothermally deposited on Ni foam via assembling of multiple metal ions (Co2+, Ni2+ and Fe2+) and 2-amino-terephthalic acid. The integrated MOF composite can directly act as a catalytic electrode, which exhibits excellent electrocatalytic HMF oxidation activity with a high current density of 100 mA cm−2 at a potential of only 1.35 V vs. RHE. More importantly, the constant potential electrolysis at 1.4 V vs. RHE in combination with chromatographic analysis reveals a high faradaic efficiency close to 100% towards the production of FDCA with a yield of 99.76%. The high electrocatalytic performance for HMF oxidation is attributed to the abundant accessible active sites of two-dimensional morphology and the optimized electronic structure of the intrinsic catalytic centers in MOFs. The present study sheds light on the rational design and synthesis of new MOF-based catalysts for biomass conversion and stimulate the extensive explorations of MOFs with tunable active sites for potential electrocatalysis applications. [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]

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]

Objectives: To evaluate the prognosis of adult severe aplastic anemia (SAA) patients with absolute neutrophil count (ANC) values of zero prior to immunosuppressive therapy (IST). Methods: Patients with ANC values of zero prior to IST were separated from very SAA and analyzed in a prospective study. All patients received IST with rabbit anti-thymocyte globulin (ATG) and cyclosporine (CsA). Results: A significantly lower response rate (RR) was identified in patients with ANC = 0 prior to IST when compared to patients with SAA after both 3 and 6 month periods or compared to those with vSAA at 3 months only. The efficacy of IST was inversely related to ANC = 0. The overall survival rate of the 'zero' group was significantly lower than that of the vSAA or SAA groups. Overall survival was closely associated with response to IST, and was inversely related to ANC = 0. Discussion: In SAA patients, ANC is associated with prognosis, the elucidated overall survival improvement in patients without ANC = 0 occurred in conjunction with decreased infection-related mortality. Our study revealed that adult patients with ANC = 0 prior to IST responded poorly to IST, suggesting that having a very low number of neutrophils was a highly predictive factor for efficacy and survival of SAA patients treated with IST. Conclusion: Adult SAA patients with ANC = 0 had a very poor prognosis and new therapeutic regimens may result in better outcome for these patients. [ABSTRACT FROM AUTHOR]

Although the roles of 5-methylcytosine and 5-hydroxymethylcytosine in epigenetic regulation of gene expression are well established, the functional effects of 5-formylcytosine and 5-carboxylcytosine on the process of transcription are not clear. Here we report a systematic study of the effects of five different forms of cytosine in DNA on mammalian and yeast RNA polymerase II transcription, providing new insights into potential functional interplay between cytosine methylation status and transcription. [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]

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.)

Background: Hepatitis B virus (HBV) infection, a liver disease caused by hepatitis B virus, may lead to serious complications such as cirrhosis and hepatocellular carcinoma. People with HBV infection may have co-infections including HIV and other hepatitis viruses (hepatitis C or D), and co-infection may increase the risk of all-cause mortality. Chronic HBV infection increases morbidity and psychological stress and is an economic burden on people with chronic hepatitis B and their families. Radix Sophorae flavescentis, an herbal medicine, is administered most often in combination with other drugs or herbs. It is believed that it decreases discomfort and prevents replication of the virus in people with chronic hepatitis B. However, the benefits and harms of Radix Sophorae flavescentis for patient-centred outcomes are not known, and its wide usage has never been established with rigorous review methodology., Objectives: To assess the benefits and harms of Radix Sophorae flavescentis versus placebo or no intervention in people with chronic hepatitis B., Search Methods: We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE Ovid, Embase Ovid, LILACS, Science Citation Index Expanded, Conference Proceedings Citation Index - Science, China National Knowledge Infrastructure (CNKI), Chongqing VIP (CQVIP), Wanfang Data, and SinoMed. We also searched the World Health Organization International Clinical Trials Registry Platform (www.who.int/ictrp), ClinicalTrials.gov (www.clinicaltrials.gov/), and the Chinese Clinical Trial Registry for ongoing or unpublished trials. We conducted the last search in December 2018., Selection Criteria: We included randomised clinical trials, irrespective of publication status, language, or blinding, comparing Radix Sophorae flavescentis versus no intervention or placebo in people with chronic hepatitis B. We excluded polyherbal blends containing Radix Sophorae flavescentis. We allowed co-interventions when the co-interventions were administered equally to all intervention groups., Data Collection and Analysis: We used standard methodological procedures expected by The Cochrane Collaboration. Review authors in pairs retrieved data from individual published reports and after correspondence with investigators. Our primary outcomes were all-cause mortality, serious adverse events, and health-related quality of life. Our secondary outcomes were hepatitis B-related mortality, hepatitis B-related morbidity, and adverse events considered 'not to be serious'. We presented meta-analysed results as risk ratios (RRs) with 95% confidence intervals (CIs). We assessed risk of bias using domains with pre-defined definitions. We conducted Trial Sequential Analyses to control the risk of random errors. We used GRADE methodology to evaluate our certainty in the evidence (i.e. "the extent of our confidence that the estimates of the effect are correct or are adequate to support a particular decision or recommendation")., Main Results: We included 35 randomised clinical trials with 3556 participants. One trial compared Radix Sophorae flavescentis with placebo; the remaining 34 trials compared effects of Radix Sophorae flavescentis in addition to a co-intervention versus the same co-intervention. The included trials assessed heterogenous forms and ways of administering Radix Sophorae flavescentis (e.g. oral capsules, oral tablets, intravenous infusion, intramuscular injection, acupoint (a specifically chosen site of acupuncture) injection) with treatment duration of 1 to 24 months. Two of the trials included children up to 14 years old. Participants in two trials had cirrhosis in addition to chronic hepatitis B. All trials were assessed at high risk of bias, and certainty of the evidence for all outcomes was very low.Only one of the 35 trials assessed mortality; no deaths occurred. Ten trials assessed serious adverse events; no serious adverse events occurred. None of the trials reported health-related quality of life, hepatitis B-related mortality, or morbidity. Adverse events considered 'not to be serious' was an outcome in 19 trials; nine of these trials had zero events in both groups. Radix Sophorae flavescentis versus placebo or no intervention showed no difference in effects on adverse events considered 'not to be serious' (RR 1.10, 95% CI 0.76 to 1.59; I² = 49%; 10 trials, 1050 participants). Radix Sophorae flavescentis showed a reduction in the proportion of participants with detectable HBV-DNA (RR 0.61, 95% CI 0.55 to 0.68; I² = 56%; 29 trials, 2914 participants) and in the proportion of participants with detectable HBeAg (hepatitis B e-antigen) (RR 0.71, 95% CI 0.66 to 0.76; I² = 19%; 20 trials, 2129 participants).Seven of the 35 randomised clinical trials received academic funding from government or hospital. Four trials received no funding. The remaining 24 trials provided no information on funding.Additionally, 432 trials lacked the methodological information needed to ensure inclusion of these trials in our review., Authors' Conclusions: The included trials lacked data on health-related quality of life, hepatitis B-related mortality, and hepatitis B-related morbidity. The effects of Radix Sophorae flavescentis on all-cause mortality and on the proportion of participants with serious adverse events and adverse events considered 'not to be serious' remain unclear. We advise caution in interpreting results showing that Radix Sophorae flavescentis reduced the proportion of people with detectable HBV-DNA and detectable HBeAg because the trials reporting on these outcomes are at high risk of bias and both outcomes are non-validated surrogate outcomes. We were unable to obtain information on the design and conduct of a large number of trials; therefore, we were deterred from including them in our review. Undisclosed funding may influence trial results and may lead to poor trial design. Given the wide usage of Radix Sophorae flavescentis, we need large, unbiased, high-quality placebo-controlled randomised trials in which patient-centred outcomes are assessed.

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.

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.