Metabolomics and transcriptomics analyses provide new insights into the nutritional quality during the endosperm development of different ploidy rice

Autotetraploid rice is developed from diploid rice by doubling the chromosomes, leading to higher nutritional quality. Nevertheless, there is little information about the abundances of different metabolites and their changes during endosperm development in autotetraploid rice. In this research, two different kinds of rice, autotetraploid rice (AJNT-4x) and diploid rice (AJNT-2x), were subjected to experiments at various time points during endosperm development. A total of 422 differential metabolites, were identified by applying a widely used metabolomics technique based on LC-MS/MS. KEGG classification and enrichment analysis showed the differences in metabolites were primarily related to biosynthesis of secondary metabolites, microbial metabolism in diverse environments, biosynthesis of cofactors, and so on. Twenty common differential metabolites were found at three developmental stages of 10, 15 and 20 DAFs, which were considered the key metabolites. To identify the regulatory genes of metabolites, the experimental material was subjected to transcriptome sequencing. The DEGs were mainly enriched in starch and sucrose metabolism at 10 DAF, and in ribosome and biosynthesis of amino acids at 15 DAF, and in biosynthesis of secondary metabolites at 20 DAF. The numbers of enriched pathways and the DEGs gradually increased with endosperm development of rice. The related metabolic pathways of rice nutritional quality are cysteine and methionine metabolism, tryptophan metabolism, lysine biosynthesis and histidine metabolism, and so on. The expression level of the genes regulating lysine content was higher in AJNT-4x than in AJNT-2x. By applying CRISPR/Cas9 gene-editing technology, we identified two novel genes, OsLC4 and OsLC3, negatively regulated lysine content. These findings offer novel insight into dynamic metabolites and genes expression variations during endosperm development of different ploidy rice, which will aid in the creation of rice varieties with better grain nutritional quality

The oyster genome reveals stress adaptation and complexity of shell formation

The Pacific oyster Crassostrea gigas belongs to one of the most species-rich but genomically poorly explored phyla, the Mollusca. Here we report the sequencing and assembly of the oyster genome using short reads and a fosmid-pooling strategy, along with transcriptomes of development and stress response and the proteome of the shell. The oyster genome is highly polymorphic and rich in repetitive sequences, with some transposable elements still actively shaping variation. Transcriptome studies reveal an extensive set of genes responding to environmental stress. The expansion of genes coding for heat shock protein 70 and inhibitors of apoptosis is probably central to the oyster's adaptation to sessile life in the highly stressful intertidal zone. Our analyses also show that shell formation in molluscs is more complex than currently understood and involves extensive participation of cells and their exosomes. The oyster genome sequence fills a void in our understanding of the Lophotrochozoa. © 2012 Macmillan Publishers Limited. All rights reserved

Dzyaloshinskii-Moriya interaction of polar magnet Fe

We propose a theoretical model with Dzyaloshinskii-Moriya interaction for the polar magnet Fe2Mo3O8. Via Wigner-Jordan transformation, the electric polarization Px and the magnetization M formula are obtained. Combined with the Green's function equation of motion method, we show that the electric polarization can be induced by a magnetic ordering and manipulated by a magnetic field. There exist structural and metamagnetic transitions in the Fe2Mo3O8 system, which is in agreement with the experimental results

Landsat-based dataset for mapping annual center-pivot irrigated cropland in Brazil

<p>Center-pivot irrigated cropland (CPIC) is a critical component of irrigation and plays an essential role in improving water use efficiency and increasing food production. To automatically extract the spatial distribution of CPIC in Brazil based on the remote sensing technology, we constructed a training dataset that supports the semantic segmentation models.</p><p>The dataset were built with the  <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/landsat-5">Landsat 5</a> , 7 and 8<a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/landsat-7"> </a> images as well as the CPIC maps from <a href="https://metadados.snirh.gov.br/geonetwork/srv/por/catalog.search#/metadata/e2d38e3f-5e62-41ad-87ab-990490841073">ANA reference</a> data. We used the Landsat images in 2005, 2010 and 2015 to build the dataset.</p><p>The samples in train_images and train_masks were used to train and valid the Convolutional Neural Network models; </p><p>The samples in valid_data were used to test the model's prediction accuracy.</p><p>Pixels with values 255 and 0 in the mask samples represent the CPIC and background categories.</p><p><strong>For technical details that used to create the dataset, please refer to </strong><i><strong>https://doi.org/</strong></i><strong>10.1016/j.isprsjprs.2023.10.007.</strong></p&gt

The Effect of Air Pollution on the Occurrence of Nonspecific Conjunctivitis

Purpose. To investigate the short-term effect of air pollution on occurrence of nonspecific conjunctivitis. Methods. Data were collected from outpatient visits from cases with conjunctivitis over a period of one year. Regression analysis was performed to evaluate the relationship between the number of outpatient visits and the air quality and the lag effect of air quality on conjunctivitis occurrence. Results. The air quality index on the day of presentation (P=0.023), one day before presentation (P=0.049), and two days before presentation day (P=0.050) had a positive relation with outpatient visits for conjunctivitis. The air quality index (P=0.001) and outpatient visits number per day (P=0.013) in autumn and winter (October to March) were significantly higher than those in spring (April) and summer (September). Conclusions. The air quality index within two days before presentation affected the probability of attending the outpatient clinic for nonspecific conjunctivitis. High number of cases can be expected in colder season

Random laser based on Rhodamine 6G (Rh6G) doped poly(methyl methacrylate) (PMMA) films coating on ZnO nanorods synthesized by hydrothermal oxidation

Random laser based on Rh6G doped PMMA thin films coating on ZnO nanorods synthesized by a simple hydrothermal oxidation method has been demonstrated. This kind of random laser medium is based on waveguide structure consisting of ZnO nanorods, Rh6G doped PMMA film and air. By controlling the time of hydrothermal oxidation reaction, wheat-like and hexagonal prism ZnO nanorods have been successfully fabricated. The emission spectra of these gain mediums based on different ZnO nanorods are different. The one based on wheat-like ZnO nanorods mainly exhibits amplified spontaneous emission, and the other one based on hexagonal prism ZnO nanorods shows random laser emission. The threshold of the random laser medium is about 73.8 μJ/pulse, and the full width at half maximum (FWHM) is around 2.1 nm. The emission spectra measured at different detecting angles reveal that the output direction is strongly confined in ±30° by the waveguide effect. Our experiments demonstrate a promising method to achieve organic random laser medium. Keywords: Random laser, ZnO nanorods, Hydrothermal oxidation, Rhodamine 6G (Rh6G), Poly(methyl methacrylate) (PMMA

Schizophrenic Core–Shell Microgels: Thermoregulated Core and Shell Swelling/Collapse by Combining UCST and LCST Phase Transitions

A variety of slightly cross-linked poly­(2-vinylpyridine)–poly­(<i>N</i>-isopropylacrylamide) (P2VP–PNIPAM) core–shell microgels with pH- and temperature-responsive characteristic were prepared via seeded emulsion polymerization. Negatively charged sodium 2,6-naphthalenedisulfonate (2,6-NDS) could be internalized into the inner core, followed by formation of (P2VPH⁺/SO₃^2–) supramolecular complex through the electrostatic attractive interaction in acid condition. The thermoresponsive characteristic feature of the (P2VPH⁺/SO₃^2–)–PNIPAM core–shell microgels was investigated by laser light scattering and UV–vis measurement, revealing an integration of upper critical solution temperature (UCST) and lower critical solution temperature (LCST) behaviors in the temperature range of 20–55 °C. The UCST performance arised from the compromised electrostatic attractive interaction between P2VPH⁺ and 2,6-NDS at elevated temperatures, while the subsequent LCST transition is correlated to the thermo-induced collapse of PNIPAM shells. The controlled release of 2,6-NDS was monitored by static fluorescence spectra as a function of temperature change. Moreover, stopped-flow equipped with a temperature-jump accessory was then employed to assess the dynamic process, suggesting a millisecond characteristic relaxation time of the 2,6-NDS diffusion process. Interestingly, the characteristic relaxation time is independent of the shell cross-link density, whereas it was significantly affected by shell thickness. We believe that these dual thermoresponsive core–shell microgels with thermotunable volume phase transition may augur promising applications in the fields of polymer science and materials, particularly for temperature-triggered release

Fabrication and Photocatalytic Properties of ZnSe Nanorod Films

ZnSe nanorod films grown on fused quartz glass substrates via a simple two-step synthesis protocol were demonstrated to be environmentally safe and effective recyclable photocatalysts. These films showed greatly enhanced photocatalytic activity compared to pulsed laser deposition ZnSe films in the degradation of methyl orange dye solutions. The well-crystalized ZnSe nanorods had a length of 15 µm and a diameter of 200 nm and were densely grown on the substrate. The morphology, crystal structure, crystal phase, and photophysical properties of the ZnSe nanorod films were investigated using field-emission scanning electron microscopy (FE-SEM), UV-Vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and high resolution transmission electron microscopy (HRTEM)

Canceling Notch Improves the Mechanical Safety of Clavicle Locking Plate: A 3D Finite Element Study

Objective Implant failure is a disastrous complication of the operative treatment of midshaft clavicle fractures, and improving the osteosynthesis plate is a strategy for preventing this. We aimed to investigate whether canceling the notch and adding screw‐hole inserts enhanced the mechanical properties of the plate. Methods A clavicle model was generated based on the CT images of six adult volunteers (age range, 20–40 years; three males and three females; height range 160–175) using dedicated software, and a midshaft fracture model was created. The domestically made seven‐hole locking plate commonly used for midshaft clavicle fractures was simulated (Model I); modifications were made to the plate (Model II). Using 3D finite element analysis, we simulated the fracture construct under three different load conditions—downward cantilever bending, axial compression, and axial torsion—and compared the stress distribution. Results We found that under axial compression, Model II experienced its maximum stress on the plate at 551.9MPa, which was less than that in Model I (790.4 MPa). Moreover, a greater stress concentration at the fracture site was observed under axial torsion, despite the maximum stress of both the models being similar. Conclusion Canceling the notch and filling the screw holes near the fracture can ameliorate stress concentration on the internal fixation construct and enhance its reliability under axial compression. This improvement has substantial effects on the mechanical properties of implants and potentially prevents implant failure. Modern osteosynthesis anatomical implants need to be improved

Risk factors associated with the prevalence of neck and shoulder pain among high school students: a cross-sectional survey in China

Abstract Background After the COVID-19 outbreak, many Chinese high school students have increased their dependence on electronic devices for studying and life, which may affect the incidence of neck and shoulder pain (NSP) in Chinese adolescents. Methods To evaluate the prevalence of NSP in high school students and its associated risk factors during COVID-19, a survey was conducted among 5,046 high school students in Shanghai, Qinghai, Henan and Macao during the second semester and summer vacation of the 2019–2020 academic year. The questionnaire included questions regarding demographic characteristics, the prevalence of NSP and lifestyle factors such as sedentary behavior, poor posture and electronic device usage. Univariable and multivariable logistic regression was used to analyze the possible influencing factors for neck and shoulder pain. Results A total of 4793 valid questionnaires (95.0%) were collected. The results indicated that the prevalence of NSP was 23.7% among high school students. Binary logistic regression analysis revealed that female gender (P < 0.05, OR = 1.82), grade (P < 0.05, range OR 1.40–1.51) and subject selection (P < 0.05, range OR 0.49–0.68) were risk factors for NSP in high school students. Sedentary behavior (P < 0.05, range OR 1.74–2.36), poor posture (P < 0.05, range OR 1.19–2.56), backpack weight (P < 0.05, range OR 1.17–1.88), exercise style and frequency (P < 0.05, range OR 1.18–1.31; P < 0.05, range OR 0.76–0.79, respectively), and the time spent using electronic devices (P < 0.05, range OR 1.23–1.38)had a significant correlation with NSP in high school students. Conclusions NSP is currently very common among high school students during the outbreak of COVID-19. Sedentary behavior, poor posture and other factors have a great impact on the occurrence of NSP in high school students. Education regarding healthy lifestyle choices should be advocated for to decrease NSP among high school students, such as more physical activity, changing poor postures and reducing the amount of time spent using electronic devices