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Expansins, which are important components of plant cell walls, act as loosening factors to directly induce turgor-driven cell wall expansion, regulate the growth and development of roots, leaves, fruits, and other plant organs, and function essentially under environmental stresses. In multiple species, many expansin genes (EXPs) have been cloned and functionally validated but little is known in pomegranate. In this study, a total of 33 PgEXPs were screened from the whole genome data of 'Taishanhong' pomegranate, belonging to the EXPA(25), EXPB(5), EXLA(1), and EXLB(2) subfamilies. Subsequently, the composition and characteristics were analyzed. Members of the same branch shared similar motif compositions and gene structures, implying they had similar biological functions. According to cis-acting element analysis, PgEXPs contained many light and hormone response elements in promoter regions. Analysis of RNA-seq data and protein interaction network indicated that PgEXP26 had relatively higher transcription levels in all pomegranate tissues and might be involved in pectin lyase protein synthesis, whilst PgEXP5 and PgEXP31 might be involved in the production of enzymes associated with cell wall formation. Quantitative real-time PCR (qRT-PCR) results revealed that PgEXP expression levels in fruit peels varied considerably across fruit developmental phases. PgEXP23 was expressed highly in the later stages of fruit development, suggesting that PgEXP23 was essential in fruit ripening. On the other hand, the PgEXP28 expression level was minimal or non-detected. Our work laid a foundation for further investigation into pomegranate expansin gene functions. [ABSTRACT FROM AUTHOR]

This study aims to explore a preparation method based on a combination of melting and ultrasound to produce a Ga2O3/ZnO (GZ) spherical composite with a snake raspberry structure for the degradation of methyl orange at room temperature in dark. The catalyst exists in the form of a (GZ) composite and an anhydrous ethanol mixture after the ultrasonic treatment of premelted GaZn liquid metal alloy in anhydrous ethanol. The degradation activity of the catalyst was evaluated according to the amount of catalyst, alloy extraction temperature, acid–base environment, and inorganic salt ions. A transmission electron microscope (TEM) was used to confirm that the material was Ga2O3 coated with ZnO, with a structure similar to that of snakeberry. The electron paramagnetic resonance (EPR) and a series of free radical inhibition experiments demonstrated that ·O2− is produced during the ultrasonic preparation of the catalyst and plays an important role in the degradation process after adding MO. The removal rate of MO reached 99.75% at 3 min. Three possible degradation pathways were proposed based on the intermediates produced during the degradation process, which were identified by liquid chromatography–mass spectrometry (LC–MS). The results of this study may provide a new choice for the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Biochar amendments have been widely used in agricultural soil for lowering N2O and NO emissions while improving soil fertility and crop performance. However, a thorough understanding of the longevity of the favorable effects would be a prerequisite for large-scale biochar application in agriculture. We conducted a three-year greenhouse vegetable trial in Southeast China to systematically investigate the impacts of biochar mixed with nitrogen (N) on soil N2O and NO emissions, vegetable performance, and soil fertility at an interannual scale. The field experiment was established in November 2016 with biochar (0, 20 and 40 t ha−1; C0, C1, and C2, respectively), applied once without/with 240 kg N ha−1 urea (N0 or N1, respectively). Soil N2O and NO emissions were monitored during the spring vegetable cultivation period, and vegetable yield, quality, and soil properties were measured after harvests in 2018, 2019, and 2020. Results indicated that N application significantly increased N2O and NO emissions and vegetable yield throughout the trial period. Biochar combined with N generally reduced N2O and NO emissions and emission factors while increasing the vegetable yield, leading to lower yield-scaled N2O and NO emissions in 2018 and 2019. Biochar markedly enhanced soil pH and organic carbon and persisted, but generally had no significant effect on N use efficiency (NUE), vegetable quality, and soil fertility index (SFI) among treatments in over-fertilized vegetable fields. Based on our results, biochar application at 20 t ha−1 combined with N seemed to achieve the highest agronomic and environmental benefits for intensive vegetable production in Southeast China. [ABSTRACT FROM AUTHOR]

A physical map has been constructed of the human genome containing 15,086 sequence-tagged sites (STSs), with an average spacing of 199 kilobases. The project involved assembly of a radiation hybrid map of the human genome containing 6193 loci and incorporated a genetic linkage map of the human genome containing 5264 loci. This information was combined with the results of STS-content screening of 10,850 loci against a yeast artificial chromosome library to produce an integrated map, anchored by the radiation hybrid and genetic maps. The map provides radiation hybrid coverage of 99 percent and physical coverage of 94 percent of the human genome. The map also represents an early step in an international project to generate a transcript map of the human genome, with more than 3235 expressed sequences localized. The STSs in the map provide a scaffold for initiating large-scale sequencing of the human genome., A physical map affording ready access to all chromosomal regions is an essential prerequisite for the international effort to sequence the entire human genome. In the shorter term, it is [...]

The popularization of silicon transistor technology has arisen because of the high‐quality native oxide passivation of the silicon surface. The high‐k oxide solution to the continuous scaling of the devices is another technology milestone. In the new era of More Moore and More than Moore, 2D semiconductor alternatives as the channel materials are of considerable interest. Major 2D candidates, however, have not demonstrated thermally induced semiconductor/native oxide interfaces, analogous to Si:SiO2, for workable devices. Recently, a prototype 2D transistor based on a native oxide high‐k stack was showcased. The transistor is based on Bi2O2Se, an emerging layered 2D semiconductor, with its native high‐k oxide, Bi2O5Se, grown by thermal oxidation. This holds great promise for the development of 2D electronics. Here, comprehensive first‐principles investigations are carried out on the fundamental electrical properties of the native oxygen and selenium vacancies in Bi2O5Se, and two other less explored oxidized forms of Bi2O2Se, i.e., Bi2O9Se3 and Bi2O10Se3, which are found to have comparable bandgap values to that of Bi2O5Se. The corresponding vacancy defect landscapes are provided as an important guideline for the developmental applications of the Bi2O2Se:Bi2OxSey stack, as a 2D analogue of Si:SiO2. [ABSTRACT FROM AUTHOR]

PdSe2 is a unique layered two-dimensional (2D) material with pentagonal structural motif and anisotropic properties. In addition, its strong interlayer interaction leads to new 2D form of the exfoliated monolayer, that is, Pd2Se3. Despite the increasing interest in these emerging 2D materials, the landscape of the native point defects, as a fundamental materials property, has not been revealed. In this work, we systematically investigate different types of defects in mono- and bi-layer PdSe2 and monolayer Pd2Se3. In contrast to the common expectation, Se vacancy is not the readily formed defect. Instead, Se-excess defects, such as SePd antisite and Se interstitial, are more likely to form over a majority of the allowed range of the atomic chemical potentials. Se-deficiency defect, Pd interstitial, is able to form under the Se-poor condition in bilayer PdSe2. The defect-mediated interlayer fusion model in the formation of monolayer Pd2Se3 from bilayer PdSe2 is reformulated. These dominant defects are found to stay in the neutral charge state, partly explaining the ambipolar behavior of the PdSe2 transistors. Finally, the stacked and lateral contacts between these few-layer semiconductors and the native Pd17Se15 metal are also studied. All these interfaces show p-type contact properties. This work reveals the important materials properties of few-layer PdSe2 and Pd2Se3 for the better development of new functional devices. [ABSTRACT FROM AUTHOR]

The strategies of substituting inorganic fertilizers with organic fertilizers have been shown to significantly impact the dynamics of soil organic carbon (SOC) combating soil degradation and climate changes in intensive vegetable production. However, the underlying mechanisms and comprehensive assessment of environmental consequences are not fully understood. We conducted a five-year field experiment in the Yangtze River Delta Alluvial Plain, China, four fertilization treatments were established at equal nitrogen (N) levels: sole mineral fertilizers (SN); organic substituting 20 % (M1N4), 50 % (M1N1), and 100 % (SM) of mineral N fertilizer with organic fertilizer. Soil carbon (C) pools, physical and chemical composition of SOC, and C footprint were measured based on soil aggregates, 13C nuclear magnetic resonance spectroscopy, and life cycle assessment to investigate the effects of organic substitution on SOC quantity, quality, and environmental implications. Our results showed a significant increase in SOC content, particularly in the M1N1 treatment. This increase was attributed to changes in soil properties, an elevation in dissolved organic C content, and improved SOC stability. Specifically, organic substitution increased the proportion of macroaggregates, content of lignin phenols, and enrichment of alkyl C groups. Based on life cycle assessment incorporating field measurements, the average C footprint ranged from 1.82 to 2.58 CO 2 kg eq kg−1 vegetable in the five-year experiment, primarily influenced by transportation and fertilizer manufacturing. Partial organic substitution reduced the C footprint by 6.2–10.1 %, while the SM treatment increased it by 0.54 CO 2 eq kg−1 vegetable, and the M1N1 had the lowest C footprint at 1.82 CO 2 eq kg−1 vegetable. As a whole, this approach of substituting 50 % of mineral N with organic fertilizers serves as a viable strategy to bolster soil C stabilization, promote C accumulation, and mitigate the C footprint linked to intensive vegetable production in subtropical regions. [Display omitted] • SOC content increased in proportion to 0–20-50–100 % organic substitution strategies. • SOC changes were driven by soil physicochemical properties and compositions. • Organic substitutions promoted SOC stabilization and reduced the C footprint. • 50 % substitution had a higher SOC increase and generated the minimum C footprint. [ABSTRACT FROM AUTHOR]