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Four prenylated indole alkaloids (1−4) were targeted isolated from the mangrove rhizosphere soil-derived fungus Penicillium janthinellum HK1-6 by using molecular networking strategies. Among them, the planar structure and relative configuration of notoamide X (1) were elucidated by detailed analysis of the spectroscopic data especially the NOESY spectrum for the first time and its absolute configuration was determined by ECD spectrum. Furthermore, curated molecular networks of MS/MS data were generated with GNPS which allowed highlighting six prenylated indole alkaloids (5, 6, 8, 9, 11, 12) that had not previously been identified in this fungus and two (7, 10) that had never been observed in any fungus. The MS/MS fragmentation pathway of these prenylated indole alkaloids was summarized. [ABSTRACT FROM AUTHOR]

The search was conducted by a combination of subject terms and free words, and the Chinese search terms included: Chinese medicine, cancer-caused fatigue, cancer fatigue, cancer, tumor, fatigue, fatigue, randomized, and control. Clinical study on Fuzheng Sanjie Jiedu recipe in the treatment of cancer-related fatigue in patients with colorectal cancer after postoperative chemotherapy. Cancer-caused fatigue originates from cancer itself, and different cancer types invade different internal organs, and different patients have a different physical constitution, so a clear standard TCM symptom score is of vital importance. On the other hand, cancer fatigue is different from ordinary illnesses, and any treatment has a big impact on the progression of cancer and the patient's condition. [Extracted from the article]

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The evaluation of rock mechanic characteristics of shale reservoir is the key for the success of fracturing. Several limitations such as complex lithology can affect the accuracy of the rock mechanic property computation. In this research, the mechanical rock properties of shale reservoirs were analyzed based on experimental tests including shale-reservoir mineral composition, uniaxial compressive strength, and triaxial compression tests. The results showed that (1) the difference in mineral composition leads to easier fracturing of sand shale reservoirs compared with pure shale reservoir. (2) Under uniaxial conditions, the rock mechanical parameters along the vertical bedding direction of sand shale reservoirs are better than pure shale reservoir parameters. The mechanical properties of shale reservoirs in parallel bedding direction are less affected by lithology. Under triaxial conditions, the confining pressure increases more than 4.0 times with the compressive strength of rocks, and the rock Young's modulus in the parallel bedding direction is higher compared with the vertical bedding direction. (3) Rock failure mode is mainly subdivided into cutting and splitting modes, and the bedding features of rock mechanic properties highly influence the drilling and fracturing operations. This study offers guidelines for the optimization of the drilling and fracturing process based on accurate evaluation of the rock mechanical properties. [ABSTRACT FROM AUTHOR]

Concise one-pot biarylamination of quinones with arylamines was developed to synthesize N -arylamine-functionalized p -iminoquinones derivatives. The approach employed AgOAc as the catalyst and (NH4)2 S2 O8 as the oxidant in the presence of 3-chlorophenylboronic acid, giving a series of N -arylamine-functionalized p -iminoquinone derivatives in moderate to good yields whereas reaction in the absence of the 3-chlorophenylboronic acid, gave a series of N -arylamine-functionalized 1,4-naphthoquinone derivatives. This catalytic approach represents a step-economic and convenient strategy for the difunctionalization of quinones. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seven new copper(ii) coordination networks combining flexible 3,3′,5,5′-tetramethyl-4,4′-bipyrazole (bpz) and diverse dicarboxylates, [Cu(bpz)0.5(adip)]n (1), [Cu2(bpz)4(sub)2]n (2), [Cu4(bpz)1.5(aze)·H2O]n (3), [Cu2(bpz)(pta)2(H2O)·H2O]n (4), [Cu2(bpz)(ipa)]n (5), [Cu2(bpz)(o-pda)2·H2O]n (6), and [Cu2(μ3-OH)(bpz)(p-pda)1.5·H2O]n (7) (H2adip = adipic acid, H2sub = suberic acid, H2aze = azelaic acid, H2pta = phthalic acid, H2ipa = isophthalic acid, H2o-pda = o-phenylenediacetic acid, H2p-pda = p-phenylenediacetic acid), have been obtained under solvothermal conditions and structurally verified by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, powder X-ray diffraction (PXRD), infrared spectroscopy (IR), UV-vis spectroscopy and thermogravimetric analyses (TGA). Single crystal X-ray diffraction analysis revealed that both 1 and 6 are 6-connected pcu networks (point symbol: {412·63}) based on paddle-wheel [Cu2(COO)4] secondary building units (SBU). Complexes 2 and 4 are 2D 44-sql networks based on a single metal ion node and a binuclear [Cu2(COO)4(H2O)] SBU, respectively, while complex 3 features an extremely rare 3D 5-connected hxg-d-5-C2/c (point symbol: {42·67·8}) network. Complex 5 shows a 1D tape structure built from bpz sealed 1D helical Cu2(ipa) chains along the b axis, and 7 is a 3D 8-connected hex (point symbol: {36·418·53·6}) network based on a centrosymmetric [Cu4(μ3-OH)2(COO)4] SBU. A thorough structural comparison of these coordination networks suggests that the coordination fashions, conformations of dicarboxylates along with the different inorganic Cu(ii) SBUs simultaneously play a significant role in constructing the diverse networks. Variable-temperature magnetic susceptibility data denote that 4 and 7 display antiferromagnetic interactions in binuclear [Cu2(COO)4(H2O)] and [Cu4(μ3-OH)2(COO)4] SBUs. Moreover, the thermal stability and UV-vis spectra of 1–7 are discussed in detail. [ABSTRACT FROM AUTHOR]

According to the requirements in real-time, accuracy and convenience characteristics of pre-warning technology in coal and gas outburst, the characteristics and regularity of electromagnetic radiation in coal and rock fracture, and regularity and relativity of electromagnetic radiation and conventional indexes during coal and gas outburst evolution were analyzed. The coal and gas outburst electromagnetic radiation warning equipment and software were developed. The pre-warning criteria of coal and gas outburst forecasting with electromagnetic radiation was built. The automatic analysis and pre-warning of electromagnetic radiation in coal and gas outburst forecasting was realized. The results showed that there was high positive correlation between electromagnetic radiation and conventional indexes of coal and gas outburst, which could reflect coal and gas outburst risk. The field application of coal and gas outburst pre-warning results showed that electromagnetic radiation had high pre-warning accuracy, and could predict outburst hazard ahead 13 meters or ahead two days. [ABSTRACT FROM AUTHOR]

The controllable key factors in magnetorheological finishing device were studied to determine their influence on efficiency of magnetorheological finishing ( MRF ) and surface of MRF, as well as interaction between efficiency and surface. Based on theoretical and experimental research, the law of material removal was explored and a new process variable based material removal model (PVMR) was proposed. The experimental findings demonstrate that PVMR reveals the law of the material removal with introduction of three concepts and makes a material removal function z (y i) where the magnetorheological finishing process parameters are considered since they are easy to control and adjust. So the material function of this model is quadratic curve function which is readily suitable for stability and online control magnetorheological finishing. [ABSTRACT FROM AUTHOR]

This letter reports high performance AlGaN solar-blind avalanche photodiodes (APDs) with separate absorption and multiplication structure grown by metal–organic chemical vapor deposition on AlN templates. In fabricating APD devices, we applied a photo-electrochemical treatment process after mesa etching to reduce damage induced by etching. After introducing this process, the leakage current of the fabricated devices was reduced obviously and a record-high gain of 1.2\times 10^4 at the reverse bias of 84 V was achieved under the measurement condition with the protection current constrained to 10^-5~A. [ABSTRACT FROM AUTHOR]

The non-coplanar substituted phenyl rings at the 9-position of a fluorenyl unit can be involved in π-electron delocalization in which the resulting oligofluorenes exhibit a very large enhancement of two-photon absorption cross sections up to 2559 GM at 710 nm. [ABSTRACT FROM AUTHOR]

GaN films with an AlxGa1−xN/AlyGa1−yN superlattice (SL) buffer layer are grown on Si(111) substrates by metal-organic chemical vapor deposition (MOCVD). The structure and strain properties of the samples are studied by optical microscopy, Raman spectroscopy, x-ray diffractometry and atomic force microscopy. The results show that the strain status and crystalline quality of the GaN layers are strongly dependent on the difference of the Al composition between AlxGa1−xN barriers and AlyGa1−yN wells in the SLs. With a large Al composition difference, the GaN film tends to generate cracks on the surface due to the severe relaxation of the SLs. Otherwise, when using a small Al composition difference, the crystalline quality of the GaN layer degrades due to the poor function of the SLs in filtering dislocations. Under an optimized condition that the Al composition difference equals 0.1, the crack-free and compressive strained GaN film with an improved crystalline quality is achieved. Therefore, the AlxGa1−xN/AlyGa1−yN SL buffer layer is a promising buffer structure for growing thick GaN films on Si substrates without crack generation. [ABSTRACT FROM AUTHOR]