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Let (U, R) be an approximation space with U being non-empty set and R being an equivalence relation on U, and let G ¯ and G ̲ be the upper approximation and the lower approximation of subset G of U. A topological rough group G is a rough group G = (G ̲ , G ¯) endowed with a topology, which is induced from the upper approximation space G ¯ , such that the product mapping f : G × G → G ¯ and the inverse mapping are continuous. In the class of topological rough groups, the relations of some separation axioms are obtained; some basic properties of the neighborhoods of the rough identity element and topological rough subgroups are investigated. In particular, some examples of topological rough groups are provided to clarify some facts about topological rough groups. Moreover, the version of open mapping theorem in the class of topological rough group is obtained. Further, some interesting open questions are posed. [ABSTRACT FROM AUTHOR]

Core-shell structured magnetic covalent organic framework (Fe3O4@COF) nanospheres were rapidly synthesized at room temperature using the monodisperse Fe3O4 nanoparticles (NPs) as magnetic core and benzene-1,3,5-tricarbaldehyde (BTA) and 3,3′-dihydroxybenzidine (DHBD) as two building blocks (denoted as Fe3O4@BTA-DHBD), respectively. They can serve as a mass spectrometry probe for rapid and high-throughput screening of bisphenols (BPs) from pharmaceuticals and personal care products (PPCPs) by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). The Fe3O4@BTA-DHBD nanospheres showed some superior features involving average pore size distribution (2.82 nm), high magnetization values (42.5 emu g−1), high specific surface area (82.96 m2 g−1), and good chemical/thermal stability. It was used as both ideal adsorbent for enrichment of BPs and new substrate to assist ionization in SELDI-TOF-MS. The method exhibited good linearity in the range 0.05–4000 ng mL−1 with correlation coefficients (r) higher than 0.9920. Low limits of detection (LODs) (500 pg mL−1 for bisphenol A (BPA), 2 pg mL−1 for bisphenol B (BPB), 28 pg mL−1 for bisphenol C (BPC), 60 pg mL−1 for bisphenol F (BPF), 33 pg mL−1 for bisphenol AF (BPAF), 200 pg mL−1 for bisphenol BP (BPBP), 10 pg mL−1 for bisphenol S (BPS), 90 pg mL−1 for tetrabromobisphenol A (BPA(Br)4), and 380 pg mL−1 for tetrabromobisphenol S (BPS(Br)4)) and good recoveries (80.6–115%) of BPs in PPCPs were achieved. The relative standard deviations (RSDs) of spot-to-spot (n = 10) and sample-to-sample (n = 5) were in the ranges 5–11% and 5–12%, respectively. The dual-function platform was successfully applied to the quantitative determination of BPs in PPCPs. It not only expanded the scope of the application of COFs but also provided an alternative strategy for the determination of hazardous compounds in PPCPs. [ABSTRACT FROM AUTHOR]

The ability of cells to repair DNA double-strand breaks (DSBs) is important for maintaining genome stability and eliminating oncogenic DNA lesions. Two distinct and complementary pathways, non-homologous end joining (NHEJ) and homologous recombination (HR), are employed by mammalian cells to repair DNA DSBs. Each pathway is tightly controlled in response to increased DSBs. The Ku heterodimer has been shown to play a regulatory role in NHEJ repair. Ku80 ubiquitination contributes to the selection of a DSB repair pathway by causing the removal of Ku heterodimers from DSB sites. However, whether Ku80 deubiquitination also plays a role in regulating DSB repair is unknown. To address this question, we performed a comprehensive study of the deubiquitinase specific for Ku80, and our study showed that the deubiquitinase OTUD5 serves as an important regulator of NHEJ repair by increasing the stability of Ku80. Further studies revealed that OTUD5 depletion impaired NHEJ repair, and hence reduced overall DSB repair. Furthermore, OTUD5-depleted cells displayed excess end resection; as a result, HR repair was facilitated by OTUD5 depletion during the S/G2 phase. In summary, our study demonstrates that OTUD5 is a specific deubiquitinase for Ku80 and establishes OTUD5 as an important and positive regulator of NHEJ repair. [ABSTRACT FROM AUTHOR]

Caffeic acid (CA), a familiar color stabilizing reagent, has aroused general concern due to its uncontrolled addition, and thus the detection of CA is increasingly important. In our report, the bright carbon dots (CDs) were prepared via hydrothermal treatment with urea and citric acid act as raw material and their characteristics were discussed through X-ray diffraction (XRD), transmission electron microscopy (TEM) and so on. Impressively, the strong emission of the as-prepared CDs (Quantum Yield: 24.3%) decreased sharply upon a full reaction with the added CA. Hence, we first present an improved strategy for determining CA based upon the quenching of the strong emission of CDs. In this strategy, 0.79-100.0 µmol L− 1 caffeic acid could be simply detected, and a detection limit of 0.24 µmol L− 1 was allowed. Additionally, CA in red wine samples can be successfully detected by this method and the exploration of the quenching mechanism of the CA-CDs system was done. [ABSTRACT FROM AUTHOR]

In this study, a new Al–17Si–2.5P master alloy has been successfully prepared to refine primary Si in hypereutectic A390 alloys. By means of electron probe microanalyzer (EPMA), a large number of AlP particles can be found in the Al–17Si–2.5P master alloy. An orthogonal L9(33) test was designed to investigate the integrated effects of refining factors including phosphorus addition level, melting temperature and holding time, and subsequently to optimize the processing parameters. It is found that under the optimized conditions, i.e., phosphorus addition of 375 ppm, melting temperature of 800 °C, and holding time of 30 min, the average sizes of primary Si can be most remarkably decreased from 116 μm to 14 μm with sphere-like morphology. Meanwhile, the Brinell hardness and tensile strength can be significantly increased by 14.1 and 27.8%, respectively. In addition, thermal analysis is also performed with differential scanning calorimeter (DSC) to analyze the solidification process of Al–18Si alloys. [ABSTRACT FROM AUTHOR]

Schizophrenia is a kind of neurodevelopmental disease. Epidemiological data associates schizophrenia with prenatal exposure to famine. Relevant prenatal protein deprivation (PPD) rodent models support this result by observing decreasing prepulse inhibition, altered hippocampal morphology and impaired memory in offspring. All these abnormalities are highly consistent with the pathophysiology of schizophrenia. We developed a prenatal famine rat model by restricting daily diet of the pregnant rat to 50% of low protein diet. A metabolomics study of prefrontal cortex was performed to integrate GC-TOFMS and UPLC-QTOFMS. Thirteen controls and thirteen famine offspring were used to differentiate in PLS-DA (partial least squares-discriminate analysis) model. Furthermore, metabolic pathways and diseases were enriched via KEGG and HMDB databases, respectively. A total of 67 important metabolites were screened out according to the multivariate analysis. Schizophrenia was the most statistical significant disease (P = 0.0016) in our famine model. These metabolites were enriched in key metabolic pathways related to energy metabolism and glutamate metabolism. Based on these important metabolites, further discussion speculated famine group was characterized by higher level of oxidized damage compared to control group. We proposed that oxidative stress might be the pathogenesis of prenatal undernutrition which is induced schizophrenia. [ABSTRACT FROM AUTHOR]

A novel method of atmospheric pressure gas chromatography-tandem mass spectrometry (APGC-MS/MS) for the analysis of organochlorine pesticides (OCPs) in human serum was developed. Better sensitivity and selectivity were achieved compared to conventional gas chromatography-mass spectrometry (GC-MS) and GC-MS/MS. The limits of detection (LODs) of OCPs ranged from 0.22 to 0.90 pg/mL for the analysis in serum samples. The recoveries and repeatability of the developed method were evaluated from the analysis of spiked serum at three levels (0.05, 0.5, and 5 ng/mL). The recoveries ranged from 84.5 to 118.2%, and the relative standard deviations (RSDs) were less than 20%. The developed APGC-MS/MS method was applied to measure OCPs in pooled human serum from the interlaboratory comparison study. The obtained results of OCPs were within the acceptable ranges. The method has been successfully applied to the analysis of OCPs in human serum samples with the sample volume of up to 100 μL. [ABSTRACT FROM AUTHOR]

The roles of the Wnt cargo receptor Wntless (Wls) during hair follicle (HF) induction and postnatal HF cycling in skin have been elucidated. However, whether Wls regulates postnatal HF morphogenesis remains unclear. In this study, we found that Wls is expressed in developing HF during the morphogenesis stage after birth. By knocking out Wls in mouse skin epithelia with hypomorphic K14-cre, we found that Wls is required for normal HF morphogenesis. Wls-deficient HFs prematurely regressed, which was possibly caused by abnormally activated TGF-β/JNK pathway. Although Wls was reported to be a direct target of the Wnt/β-catenin pathway, we found that epithelial β-catenin was not necessary to maintain Wls expression. Therefore, other signals are involved in regulating Wls transcription in mouse skin. [ABSTRACT FROM AUTHOR]

To estimate inoculum density of Phytophthora sojae in natural soils to predict disease risk and to study the ecology of P. sojae in the soil, we developed two bioassays to quantify zoospores and another for oospores of P. sojae in soil based on inoculation of Mollisol (the most conducive soil type for this disease according to our disease survey) with a known density of zoospores or oospores of enhanced green fluorescent protein (EGFP)-labeled P. sojae Eps597-3 (pathotype 1a3c7). A linear regression equation, $$ y_{ 1} = 1.0 9 2 7x_{ 1} + 7. 3 6 5 2 $$ (Eq. 1), and an index regression equation, $$ {\text{y}}_{ 2} \, \;{ = }\; 1 8 6 2. 9 {\text{e}}^{{0.00 9 5 {\text{x}}_{ 2} }} $$ (Eq. 2), were established to quantify the zoospores in the soil, where x is the concentration of zoospores counted directly using a light microscope and y is the concentration of zoospores added to a soil suspension, x is the number of zoospores at the margin of 18 leaf discs, and y is the number of zoospores added to 10 mL of a soil suspension. Another linear regression equation, $$ y_{ 3} = 3. 3 8 3 6x_{ 3} + 20 7.0 5 $$ (Eq. 3), was determined to quantify the oospores in the soil, where x is the number of zoosporangia at the margin of 18 leaf discs, and y is the number of oospores added to 10 mL of a soil suspension. These three equations provided high reproducibility and accuracy. To verify their applicability, two other isolates with different pathotypes (3a3b678 and 1a1d23a3c578) and two other soil types (Albic luvisols and Aquic cambosols) were tested. Pathotype and soil type did not markedly affect the parameters in the three equations, suggesting that these three equations are accurate enough to serve as universal quantification bioassays of live zoospores and oospores of P. sojae isolates of any pathotype in any soil. Equations (1) and (2) can be used only to estimate zoospores, Eq. (2) for zoospores, and Eq. (3) for oospores of P. sojae in natural or inoculated soil. This method can be finished within 2-3 h for Eq. (1), 4-5 h for Eq. (2), and 7-10 days for Eq. (3). [ABSTRACT FROM AUTHOR]

We report a trap-assisted photomultiplication (PM) phenomenon in solution-processed polymer photodetectors (PPDs) based on P3HT:PC71BM as the active layer, the maximum EQE of 16,700% is obtained for the PPDs with PC71BM doping weight ratio of 1%. The PM phenomenon is attributed to the enhanced hole tunneling injection assisted by trapped electrons in PC71BM near Al cathode, which can be demonstrated by the transient photocurrent curves and EQE spectra of PPDs with different PC71BM doping ratios. The positive effect of trapped electrons in PC71BM near Al cathode on the hole tunneling injection is further confirmed by the simulated optical field and exciton generation rate distributions in the active layer and the EQE spectra of PPDs with Al(1)/P3HT:PC71BM(100:1)/Al(2) device structure under forward and reverse biases. This discovery may open a new road for organic materials to be used in highly sensitive photodetectors while preserving the advantages of organic materials. [ABSTRACT FROM AUTHOR]