The purpose of the study is to discuss the process of construct the writing teaching mode based on Rain Classroom and explore the effects of the writing teaching mode based on Rain Classroom on ...College English teaching. This paper concludes that the main links of the writing teaching mode based on Rain Classroom are: model text analysis, imitation exercise, practical writing, and mutual evaluation and revision. In addition, the writing teaching mode based on Rain Classroom has significant effect on improving college students' English writing ability.
The purpose of the study is to introduce a new Model of Coarticulation, namely, Degree of Articulatory Dispersion. This paper reviews the Models of Coarticulation, and then the validity of the Degree ...of Articulatory Dispersion is proved by finding the correlation between the dispersion of DAD and the slope of LEM in the four groups of Monguor consonants classified by the manner of articulation. The finding shows that there is a significant negative correlation between the dispersion of DAD and the slope of LEM. Therefore, Degree of Articulatory Dispersion can be a valid Model of Coarticulation to measure the degree of coarticulation.
The purpose of the study is to discuss acoustic effects of consonant positions on monophthongs in Monguor language and whether the preceding and the subsequent consonants have the same effect on the ...coarticulation COD of monophthongs. This paper concludes that both in the CV structure and in the VC structure, the monophthongs with the tongue back, the tongue high, and the lip round are more likely to be influenced by their preceding or subsequent consonants. In addition, the lower the tongue, the smaller the coarticulation COD of vowels.
The purpose of the study is to discuss the process of constructing the blended teaching mode based on Rain Classroom and explore the effects of blended teaching mode based on Rain Classroom on ...College English teaching. This paper concludes that the main components of the blended teaching mode based on Rain Classroom are pre-class study, during-class interaction, and after-class review and expansion. In addition, the blended teaching mode based on Rain Classroom has significant effect on improving college students' comprehensive language level.
The purpose of the study is to discuss the transitional modes for triphthongs in Monguor language and whether the preceding consonants have significant effect on the transitional modes of ...triphthongs. This paper concludes that the change rates of the first parts for F1 or F2 are higher than those of the second parts, and the first parts for F1 or F2 are the transitional segments, and the second parts for F1 or F2 stable segments. In addition, the preceding consonants have significant effect on the transitional modes of triphthongs from the perspective of change rates.
Land use and related pressures have reduced local terrestrial biodiversity, but it is unclear how the magnitude of change relates to the recently proposed planetary boundary ("safe limit"). We ...estimate that land use and related pressures have already reduced local biodiversity intactness–the average proportion of natural biodiversity remaining in local ecosystems–beyond its recently proposed planetary boundary across 58.1% of the world's land surface, where 71.4% of the human population live. Biodiversity intactness within most biomes (especially grassland biomes), most biodiversity hotspots, and even some wilderness areas is inferred to be beyond the boundary. Such widespread transgression of safe limits suggests that biodiversity loss, if unchecked, will undermine efforts toward long-term sustainable development.
•Studies with information on PM2.5 and NO2 measurement error structures were reviewed.•We derived outdoor source personal exposure to compare with ambient concentrations.•Outdoor sources contribute ...44% to total personal exposure to PM2.5 and 74% for NO2.•Mean difference (measurement error) was 5.72 μg/m3 for PM2.5 and 7.17 ppb for NO2.•Error variability was also greater for NO2. Error correlation was not reported.
The use of proxy exposure estimates for PM2.5 and NO2 in air pollution studies instead of personal exposures, introduces measurement error, which can produce biased epidemiological effect estimates. Most studies consider total personal exposure as the gold standard. However, when studying the effects of ambient air pollution, personal exposure from outdoor sources is the exposure of interest.
We assessed the magnitude and variability of exposure measurement error by conducting a systematic review of the differences between personal exposures from outdoor sources and the corresponding measurements for ambient concentrations in order to increase understanding of the measurement error structures of the pollutants.
We reviewed the literature (ISI Web of Science, Medline, 2000–2016) for English language studies (in any age group in any location (NO2) or Europe and North America (PM2.5)) that reported repeated measurements over time both for personal and ambient PM2.5 or NO2 concentrations. Only a few studies reported personal exposure from outdoor sources. We also collected data for infiltration factors and time-activity patterns of the individuals in order to estimate personal exposures from outdoor sources in every study.
Studies using modelled rather than monitored exposures were excluded. Type of personal exposure monitor was assessed. Random effects meta-analysis was conducted to quantify exposure error as the mean difference between “true” and proxy measures.
Thirty-two papers for PM2.5 and 24 for NO2 were identified. Outdoor sources were found to contribute 44% (range: 33–55%) of total personal exposure to PM2.5 and 74% (range: 57–88%) to NO2. Overall estimates of personal exposure (24-hour averages) from outdoor sources were 9.3 μg/m3 and 12.0 ppb for PM2.5 and NO2 respectively, while the corresponding difference between these exposures and the ambient concentrations (i.e. the measurement error) was 5.72 μg/m3 and 7.17 ppb. Our findings indicated also higher error variability for NO2 than PM2.5. Large heterogeneity was observed which was not explained sufficiently by geographical location or age group of the study sample.
Relying only on information available in published studies led to some limitations: the contribution of outdoor sources to total personal exposure for NO2 had to be inferred, individual variation in exposure misclassification was unavailable and instrument error could not be addressed. The larger magnitude and variability of errors for NO2 compared with PM2.5 has implications for biases in the health effect estimates of multi-pollutant epidemiological models. Results suggest that further research is needed regarding personal exposure studies and measurement error bias in epidemiological models.
Spatially resolved proteomics is an emerging approach for mapping proteome heterogeneity of biological samples, however, it remains technically challenging due to the complexity of the tissue ...microsampling techniques and mass spectrometry analysis of nanoscale specimen volumes. Here, we describe a spatially resolved proteomics method based on the combination of tissue expansion with mass spectrometry-based proteomics, which we call Expansion Proteomics (ProteomEx). ProteomEx enables quantitative profiling of the spatial variability of the proteome in mammalian tissues at ~160 µm lateral resolution, equivalent to the tissue volume of 0.61 nL, using manual microsampling without the need for custom or special equipment. We validated and demonstrated the utility of ProteomEx for streamlined large-scale proteomics profiling of biological tissues including brain, liver, and breast cancer. We further applied ProteomEx for identifying proteins associated with Alzheimer's disease in a mouse model by comparative proteomic analysis of brain subregions.
Abstract
Spectrally diverse fluorescent proteins (FPs) provide straightforward means for multiplexed imaging of biological systems. Among FPs fitting standard color channels, blue FPs (BFPs) are ...characterized by lower brightness compared to other spectral counterparts. Furthermore, available BFPs were not systematically characterized for imaging in cultured mammalian cells and common model organisms. Here we introduce a pair of new BFPs, named Electra1 and Electra2, developed through hierarchical screening in bacterial and mammalian cells using a novel dual-expression vector. We performed systematic benchmarking of Electras against state-of-art BFPs in cultured mammalian cells and demonstrated their utility as fluorescent tags for structural proteins. The Electras variants were validated for multicolor neuroimaging in
Caenorhabditis elegans
, zebrafish larvae, and mice in comparison with one of the best in the class BFP mTagBFP2 using one-photon and two-photon microscopy. The developed BFPs are suitable for multicolor imaging of cultured cells and model organisms in vivo. We believe that the described dual-expression vector has a great potential to be adopted by protein engineers for directed molecular evolution of FPs.
F-box and WD-40 domain protein 7 (Fbxw7) is a component of the Skp1-Cdc53/Cullin-F-box-protein complex (SCF/β-TrCP), which is an E3 ubiquitin ligase that mediates protein degradation. This complex ...has recently been shown to negatively regulate spermatogonial stem cell self-renewal; however, its roles in Sertoli cell (SC) proliferation, differentiation, and function remain to be established. In this study, we generated conditional mutant mice with SC-specific deletion of Fbxw7 via the Cre-loxP system. Fbxw7 deficiency in SCs impaired testis development, which is characterized by age-dependent tubular atrophy, excessive germ cell loss, and spermatogenic arrest, and the mutant males were infertile at 7 months old. Fbxw7 ablation also compromised cytoskeletal organization and cell polarity of SCs, as well as integrity of the blood-testis barrier. In addition, the transcript levels of cell markers for germ cells, Leydig cells, and SCs were significantly decreased in Fbxw7 mutant mice. Importantly, protein levels of GATA-4, a transcription factor that plays a crucial role in SC maturation and testis development, were progressively decreased in control SCs after postnatal day 14, whereas levels were aberrantly elevated in Fbxw7-deleted SCs. Interestingly, the Gata-4 messenger RNA levels remained stable following Fbxw7 deletion. Fbxw7 silencing in SCs also induced progressive Leydig cell inefficiency and testosterone insufficiency. Collectively, these results demonstrate that Fbxw7 expression is required for SC maturation and function, potentially through degradation of GATA-4, to support pubertal testis development and spermatogenesis. Summary sentence Fbxw7 is essential for pubertal testis development and spermatogenesis by regulating SC maturation and function, potentially through degradation of GATA-4.
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