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In this study, we present a straightforward and environmentally friendly electrochemical approach for achieving selective halogenation of N‐heteroarenes, including indoles, diazoles, pyrroles, quinolinone, and naphthols. Our method utilizes commercially available and affordable ammonium halides as halogen source. A library of valuable halogenated N‐heteroarenes can be synthesized in moderate to excellent yields under mild conditions (transition‐metal‐free, oxidant‐free, ethanol as solvent, atmospheric environment). The approach demonstrates a broad substrate scope, excellent tolerance towards various functional groups, and scalability. [ABSTRACT FROM AUTHOR]

17β-19-nortestosterone (17β-NT) has been illegally used in antifatigue functional foods to promote muscle growth and improve endurance. A rapid and sensitive solid-phase extraction–enzyme-linked immunosorbent assay (SPE-ELISA) method was developed and successfully applied to analyze the levels of 17β-NT in antifatigue functional foods. A polyclonal antibody against 17β-NT was produced from rabbits immunized with the 17β-NT-BSA conjugate, and a competitive direct enzyme-linked immunosorbent assay was developed for the rapid detection of 17β-NT. The concentration causing 50% inhibition ( IC50) and the limit of detection (LOD) were found to be 0.08 and 0.0055 ng/mL, respectively; this was better than methods previously reported that had a LOD of 2.4 ng/mL. C18 cartridges were investigated for use in removing the effects of matrix in foods, and the sample purification protocol was optimized. Using the developed SPE-ELISA method, recoveries of functional food samples were obtained in the range of 71% to 91.5%. Moreover, 2 kinds of antifatigue functional foods were analyzed using the established ELISA and HPLC methods. The correlation coefficient of the results obtained using the 2 methods was greater than 0.98. Thus, the preliminary evaluation of the SPE-ELISA method proved that it is a specific, sensitive, and precise tool that can be used for the practical detection of 17β-NT in various antifatigue functional food samples. [ABSTRACT FROM AUTHOR]

BACKGROUND: The long-standing goal of a preclinical diagnostic test for transmissible spongiform encephalopathy (TSE) has recently become urgent because of the discovery that humans with variant Creutzfeldt-Jakob disease can transmit disease via blood transfusions. STUDY DESIGN AND METHODS: The misfolded protein diagnostic (MPD) assay employs a pyrene-labeled palindromic sequence of prion peptides that undergoes a cascade of coil to β-sheet conversion in the presence of the misfolded prion protein (PrPTSE). The ability of the assay to detect PrPTSE in brain, serum, and plasma was tested. The basic protocol involved a several-hour incubation of 200-µL sample volumes with the peptide reagent in 96-well plates, after which fluorescence was monitored by a fluorescence plate reader with an excitation wavelength of 350 nm and emission scanning wavelength range of 365 to 600 nm. RESULTS: Target specificity for PrPTSE was documented by correlation of assay signal with Western blot signals in brain tissue from TSE-infected, normal, and knockout mice and negative assay signals by use of reagents with different peptide sequences. When applied to plasma or serum, the assay discriminated between samples from a variety of experimental and natural TSE infections compared to uninfected controls, with a sensitivity threshold of approximately 1 infectious dose per mL in pooled plasma from TSE-infected mice. CONCLUSIONS: The MPD assay is a sensitive and specific test for the detection of PrPTSE that may be useful in both preclinical and clinical diagnosis of TSE diseases of animals and humans. [ABSTRACT FROM AUTHOR]

OBJECTIVES: To assess the effectiveness and safety of additional bedtime H2-receptor antagonists (H2RAs) in suppressing nocturnal gastric acid breakthrough (NAB) via a systematic review. METHODS: Eligible trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 2, 2004), MEDLINE (January 1966–June 2004), EMBASE (January 1980–June 2004) and CINAHL (January 1982–June 2004). Additional hand-searching was conducted on the proceedings of correlated conferences, eight important Chinese journals and references of all included trials. All randomized controlled trials evaluating H2RAs for the control of NAB were eligible for inclusion. The systematic review was conducted using methods recommended by The Cochrane Collaboration. RESULTS: Only two randomized crossover studies, comprising 32 participants, met the inclusion criteria. Because the design, dosage and duration of the treatments were different between the studies, it was not possible to conduct meta-analysis. There were no consistent conclusions found between the two included studies in evaluating H2RAs for the control of NAB. CONCLUSIONS: No implications for practice at this stage can be concluded. Appropriately designed large-scale randomized controlled trials with long-term follow up are needed to determine the effects of additional bedtime H2RAs in suppressing NAB. [ABSTRACT FROM AUTHOR]

Although the synthesis of α‐tertiary amino acids (ATAAs) has been extensively studied, the development of an inexpensive and facile methodology to incorporate multifunctionality on ATAAs remains challenging. In this article, we present a single‐step radical approach for the modular synthesis of functionally diverse ATAAs. This synthesis takes place under mild conditions with an absence of metals, photocatalysts, and all other additives. We demonstrate the broad applications of this approach on a variety of aliphatic and aromatic carboxylic acids, alkenes, 1,3‐enynes, and oxazolones. The results prove that our method provides excellent functional group tolerance and late‐stage applicability, as well as gram‐scale synthesis via flow chemistry. Additionally, we include mechanistic studies which reveal that the excited state of oxazolone enolate upon light excitation is a key intermediate that acts as a radical precursor and an efficient reductant. [ABSTRACT FROM AUTHOR]

Although the synthesis of α‐tertiary amino acids (ATAAs) has been extensively studied, the development of an inexpensive and facile methodology to incorporate multifunctionality on ATAAs remains challenging. In this article, we present a single‐step radical approach for the modular synthesis of functionally diverse ATAAs. This synthesis takes place under mild conditions with an absence of metals, photocatalysts, and all other additives. We demonstrate the broad applications of this approach on a variety of aliphatic and aromatic carboxylic acids, alkenes, 1,3‐enynes, and oxazolones. The results prove that our method provides excellent functional group tolerance and late‐stage applicability, as well as gram‐scale synthesis via flow chemistry. Additionally, we include mechanistic studies which reveal that the excited state of oxazolone enolate upon light excitation is a key intermediate that acts as a radical precursor and an efficient reductant. [ABSTRACT FROM AUTHOR]

The temperature-dependent photophysical properties of a series of 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) derivatives with different oligo(ethylene glycol) (OEG) dendrons were investigated. Weak fluorescence emission was observed for these BODIPY derivatives in dilute solution with low viscosity. BDP-G0 and BDP-G1-TEG exhibit a high quantum yield in viscous glycerol solutions, contrary to the moderate and little fluorescence enhancement for BDP-G1 and BDP-G2 under the same conditions. The photoinduced electron transfer (PET) may have quenched the fluorescence, as supported by calculation. Interestingly, the thermoresponsive BODIPY derivatives show heat-induced luminescence enhancement with a high signal-to-noise ratio and their emission maxima are dependent on the structures of branched tri(ethylene glycol) moieties. Finally, preliminary studies on the BODIPY derivatives as intracellular fluorescence indicators in living HeLa cells were carried out. [ABSTRACT FROM AUTHOR]

Wheat is one of the most common and productive crops in the world, and the growth and production of wheat are sensitive to climate change. Climate change affects wheat phenology by influencing sowing/maturity dates and the duration of growing stages, and ultimately affects the grain yield. Reliable prediction of changes in wheat yield is significant for maintaining global food security. However, studies addressing the potential impact of crop phenology changes on grain yield are rarely reported, which is a big challenge. Using the CERES-Wheat model and first-order differential equation models, we quantified the impact of future climate change on wheat phenology and grain yield for two periods (P1: 2011-2040; P2: 2041-2070) under three representative concentration pathways (RCP2.6, RCP4.5, RCP8.5) in China's twomain wheat-growing areas (Northwest SpringWheat-Growing Area(NWSWA) and Huang-Huai-Hai Winter Wheat-Growing Area (HHWWA)); the baseline period was 1981-2010. Accumulated thermal time during thewhole growing period (WGP) tends to significantly increase in NWSWA and HHWWA under all RCPs and periods. This rising accumulated thermal time will reduce the time to anthesis and maturity and shorten the vegetative growing period (VGP), reproductive growing period (RGP), and theWGP. In P2, spring wheat grain yield is projected to diminish by a regional average of 2.67% for RCP2.6, 4.07% for RCP4.5, and 5.66% for RCP8.5, which is dominated by the lower accumulated solar radiation during the VGP in NWSWA. Additionally, for the winter wheat grain yield in HHWWA in P2, its grain yield reduction is projected to decline by 4.8% (RCP2.6), 7.9% (RCP4.5), and 9.8% (RCP8.5), which is caused by increasing accumulated thermal time in the VGP. These results suggest that breeding high-temperature-tolerant varieties with high calorie requirements is an adaptive strategy to mitigate the negative impact of climate change on wheat yield in the study areas. [ABSTRACT FROM AUTHOR]

The Old World buntings (Aves: Emberizidae) mainly inhabit open habitats in Eurasia and Africa. It has long been debated whether the group originated in the New World or the Old World and whether their radiation is related to the expansion of open habitats and shifts in migratory behaviours. To answer these questions, we reconstructed their biogeographic histories and analysed their diversification patterns in terms of time, space and traits using a near-complete phylogeny. We found the most recent common ancestor of Emberizidae and their sisters distributed in the New World. After invasion into the eastern Palearctic through the Bering Straits Bridge in the middle Miocene, subsequent loss of migrations probably split Emberizidae into two lineages: one radiated in Afrotropical deserts and savannah and the other mainly diversified in Palearctic semi-open to open forests, the mountains of Central Asia and the Qinghai-Tibetan Plateau. This group began to diversify in the late Miocene (~10 Ma), at first rapidly, coinciding with the expansion of open habitats due to global cooling. As the available habitats were occupied, the diversification rate of buntings decreased rapidly in arid habitats, but shifts of habitat preference to open forests led to terminal radiations on the southern edge of taiga forests in the mountains of Central Asia and the eastern Palearctic. Our results provide insight into the biogeographic histories and radiation of the Old World buntings in open habitats. [ABSTRACT FROM AUTHOR]

A novel miniaturised dual‐band bandpass filter using a single modified stepped impedance resonator (SIR) is presented. Some different shaped slots cutting on the middle patch of the SIR are adopted to improve the return loss in the two passbands and control the resonant frequencies. Meanwhile, the impedance ratio can be changed by changing L or W to tune the resonant frequencies. To improve the selectivity and achieve a high out‐of‐band rejection, source–load coupling is utilised. The simulated and measured results are presented and show good agreement. [ABSTRACT FROM AUTHOR]

A novel BODIPY-based fluorescent thermometer, which shows a lysosome-targeting property, was successfully prepared. Due to the electron-donating ability of the oligo(ethylene glycols), the photoinduced electron-transfer pathway from morpholine to BODIPY dye is blocked. The fluorescence of the thermometer quenched by intramolecular rotation at room temperature was progressively enhanced during heating due to the increased microviscosity around the fluorophore. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m6A) is an abundant internal modification in eukaryotic mRNA and plays regulatory roles in mRNA metabolism. However, methods to precisely locate the m6A modification remain limited.We present here a photocrosslinking- assisted m6A sequencing strategy (PA-m6A-seq) to more accurately define sites with m6A modification. Using this strategy, we obtained a high-resolution map of m6A in a human transcriptome. The map resembles the general distribution pattern observed previously, and reveals new m6A sites at base resolution. Our results provide insight into the relationship between the methylation regions and the binding sites of RNA-binding proteins. [ABSTRACT FROM AUTHOR]

Oncogenic Ras induces cell‐cycle arrest in mammalian cells and in fertilized Xenopus eggs. How oncogenic Ras induces cell‐cycle arrest remains unclear. We previously showed that oncogenic Ras induces cell‐cycle arrest in activated Xenopus egg extracts (cycling extracts) and that the induced cell‐cycle arrest correlates with hyperphosphorylation of a 32 kDa protein. However, the identity of the 32 kDa protein was not known. By using a sucrose density‐gradient centrifugation, Triton X‐100–acetic acid–urea (TAU)‐gel electrophoresis, composite agarose‐polyacrylamide gel electrophoresis (CAPAGE), SDS–PAGE, and partial tryptic peptide sequence analysis, the 32 kDa protein has now been identified as S6, a 40S subunit ribosomal protein. Hence, our results indicate that the oncogenic Ras‐induced cell‐cycle arrest is correlated with hyperphosphorylation of S6, suggesting that phosphorylation of S6 plays an important role in the induced cell‐cycle arrest. It has been shown that conditional deletion of gene encoding S6 in mammalian cells prevents proliferation, demonstrating the importance of S6 in cell proliferation. The exact role S6 plays in cell proliferation is unclear. However, phosphorylation of S6 has been implicated in the regulation of protein synthesis. Thus, our results are consistent with the concept that oncogenic Ras induces S6 phosphorylation to influence protein synthesis, thereby contributing to the cell‐cycle arrest. In addition, our results also demonstrate that composite agarose‐polyacrylamide gel electrophoresis is suitable for the separation of large molecular complexes. © 2004 Wiley‐Liss, Inc. [ABSTRACT FROM AUTHOR]