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Cadmium (Cd) contamination in soils and accumulation in cereal grains have posed food security risks and serious health concerns worldwide. Understanding the Cd transport process and its management for minimizing Cd accumulation in cereals may help to improve crop growth and grain quality. In this review, we summarize Cd uptake, translocation, and accumulation mechanisms in cereal crops and discuss efficient measures to reduce Cd uptake as well as potential remediation strategies, including the applications of plant growth regulators, microbes, nanoparticles, and cropping systems and developing low-Cd grain cultivars by CRISPR/Cas9. In addition, miRNAs modulate Cd translocation, and accumulation in crops through the regulation of their target genes was revealed. Combined use of multiple remediation methods may successfully decrease Cd concentrations in cereals. The findings in this review provide some insights into innovative and applicable approaches for reducing Cd accumulation in cereal grains and sustainable management of Cd-contaminated paddy fields.

As a special gas target with large aspect ratio, the planar symmetric gas jet has attracted some interests in High Harmonic Generation (HHG). It can be produced by gas adiabatic expansion through a supersonic slit nozzle into vacuum. In this work, the spatial distributions of atomic density are investigated in detail along the short side, the long side and the gas jet flow of the planar symmetric argon gas jet based on ANSYS Fluent. The results indicate that along the long side, the planar symmetric jet provides the advantages of high atomic density and the large dimension of uniform atomic density distribution. The density distribution profile is similar to the Gaussian one along the short side. The atomic density at the center of the jet outside the nozzle is lower and decreases much faster than that expected by idealized straight streamline model due to the lateral expansion of gas jet at slit nozzle width.

We studied the influences that 3d transition metals have on the cohesive energies, structural changes and operating voltages of P2-NaxMO2 during discharge based on first-principles calculations.

Oxaliplatin-based chemotherapy is a standard treatment for advanced colorectal cancer (CRC) patients. However, chemoresistance-induced resistance is an essential cause for mortality. Therefore, it is necessary to study the mechanism of drug resistance in CRC.Here, we established two strains of patient-derived organoids (PDOs) selected from oxaliplatin-resistant and treatment-naïve CRC patients. To dissect the drug-resistant mechanisms, these CRC-PDOs were subjected to single-cell RNA sequencing (scRNA-Seq).We found that the drug sensitivity test outcome from these organoids subjected to oxaliplatin and 5-FU exposure was consistent with the clinic readout. CRC-PDOs well recapitulated the morphology and histology of their parental biopsies based on HE and IHC staining of pathological biomarkers. The scRNA-Seq data filtered drug-resistant cell populations and related signaling pathways (e.g. oxidative phosphorylation and ATP metabolic process). The data also revealed several putative drug resistant-driven genes (STMN1, VEGFA and NDRG1) and transcription factors (E2F1, BRCA1, MYBL2, CDX2 and CDX1).We generated an oxaliplatin-resistant CRC organoid model that was employed to provide potential therapeutic targets for treating CRC patients exhibiting oxaliplatin-resistance.

Plastic particles of diameters ranging from 1 to 1000 nm and 1 µm to 5 mm are respectively known as nanoplastics and microplastics, and are collectively termed micro(nano)plastics (MNPs). They are ubiquitously present in aquatic and terrestrial environments, posing adverse multifaceted ecological impacts. Recent transgenerational studies have demonstrated that MNPs negatively impact both the exposed parents and their unexposed generations. Therefore, this review summarizes the available research on the transgenerational impacts of MNPs in aquatic and terrestrial organisms, induced by exposure to MNPs alone or in combination with other organic and inorganic chemicals. The most commonly reported transgenerational effects of MNPs include tissue bioaccumulation and transfer, affecting organisms' survival, growth, reproduction, and energy metabolism; inducing oxidative stress; enzyme and genetic responses; and causing tissue damage. Similarly, co-exposure to MNPs and chemicals (organic and inorganic pollutants) significantly impacts survival, growth, and reproduction and induces oxidative stress, thyroid disruption, and genetic toxicity in organisms. The characteristics of MNPs (degree of aging, size, shape, polymer type, and concentration), exposure type and duration (parental exposure vs. multigenerational exposure and acute exposure vs. chronic exposure), and MNP-chemical interactions are the main factors affecting transgenerational impacts. Selecting MNP properties based on their realistic environmental behavior, employing more diverse animal models, and considering chronic exposure and MNP-chemical mixture exposure are salient research prospects for an in-depth understanding of the transgenerational impacts of MNPs.

Nanoplastics (NPs) are good carriers of persistent organic pollutants (POPs) such as polybrominated diphenyl ethers (PBDEs) and can modify their bioavailability and toxicity to aquatic organisms. This study highlights the single and combined toxic effects of polystyrene nanoplastics (PS-NPs) and 2,2 ',4,4 '-tetrabromodiphenyl ether (BDE-47, one of the major PBDE congeners) on zebrafish embryos after an exposure of up to 120 hpf. Our results showed that PS-NPs and BDE-47 formed larger particle aggregates during co-exposure, which attached to the surface of the yolk membrane and even changed its structure, and these particles also bioaccumulated in the intestine of zebrafish larvae, compared with the PS-NPs single exposure. Further, the co-exposure significantly increased mortality, accelerated voluntary movements, enhanced hatching rate, and decreased heart rate. Hepatoxicity analyses revealed that the mixture exposure induced a darker/browner liver colour, atrophied liver and greater hepatotoxicity in zebrafish larvae. In addition to increased ROS accumulation, the reduced expression of the antioxidant gpx1a gene and increased expression of cyp1a1 were found after co-treatment. Moreover, ache and chrn7α genes associated with neurocentral development, were significantly downregulated, mainly in the co-exposure group. In conclusion, simultaneous exposure to PS-NPs and BDE-47 exacerbated oxidative stress, developmental impacts, hepatotoxicity, and neurodevelopmental toxicity in zebrafish larvae. Therefore, neurotoxic effects of complex chemical interactions between PS-NPs and persistent organic pollutants in freshwater environments should be paid more attention.

Organic pollutants such as di-(2-ethylhexyl) phthalate (DEHP) interact with nanoplastics (NPs) and change their bioavailability and toxicity to aquatic organisms. This study aims to assess the ecotoxicological impacts of NPs in the presence and absence of DEHP on juvenile largemouth bass (LMB) Micropterus salmoides. Therefore, LMB was fed with diets containing various concentrations (0, 2, 10, and 40 mg/g) of polystyrene nanoplastics (PSNPs) by the weight of diets. After a 21-day of PSNPs dietary exposure, LMB was treated with DEHP at 450 μg/L through waterborne exposure for three days. Our results showed that PSNPs were accumulated in the intestinal tissues, which significantly decreased the feeding and growth rates in LMB. The histopathological analysis showed the intestine and liver of LMB were subjected to various degrees of structural damage caused by PSNPs, and DEHP-PSNP co-exposure enhanced those histopathological damages in both tissues. Additionally, the co-exposure induced oxidative stress in terms of increased activities of glutathione S-transferase, catalase, and superoxide dismutase enzymes in the liver, intestine, spleen, and serum. Furthermore, the co-exposure significantly changed the intestinal microbial composition, i.e., the decrease in the abundance of probiotics (Bacteroidetes and Proteobacteria) and the increase in pathogenic bacteria (Firmicutes) posed a great threat to fish metabolism and health. Therefore, this study highlights that the presence of DEHP enhances the toxicity of NPs on LMB in freshwater and suggests the regulated use of plastic and its additives for improving the health status of aquaculture fish for food safety in humans.

The widespread occurrence of microplastics (MPs) in aquatic ecosystems that caused environmental pollution has attracted worldwide attention. Herein, graphene electrode was initially derived from petroleum waste. Then the electrochemical responses of the electrode were evaluated using electrochemical impedance spectroscopy (EIS) toward polystyrene (PS) under various optimum conditions. For the quantitative measurement of PS concentration, principal component analysis (PCA) score images displayed that the data points offered the best discrimination of the classes, and singular value decomposition (SVD) showed that a good linearity was achieved between Z"u(1) and lgC

Formation of pure gaseous water cluster in the supersonic gas flow from a conical nozzle was investigated by simulation. The simulation results show that average size of water cluster indicates a different size evolution along the gas flow, i.e., the average cluster size firstly increases to a maximum size and then decreases slowly, rather than keeps increasing like other gases. By further calculations of the nucleation rate and the growth rate of water cluster, it is found that the decrease of average size results from a high nucleation rate and a low size growth rate in the downstream of gas flow far away from conical nozzle throat. Formation of pure gaseous water cluster in the supersonic gas flow from a conical nozzle was investigated by simulation. The simulation results show that average size of water cluster indicates a different size evolution along the gas flow, i.e., the average cluster size firstly increases to a maximum size and then decreases slowly, rather than keeps increasing like other gases.

Grain weight and grain number, the two important yield traits, are mainly determined by grain size and panicle architecture in rice. Herein, we report the identification and functional analysis of OsSPL4 in panicle and grain development of rice. Using CRISPR/Cas9 system, two elite alleles of OsSPL4 were obtained, which exhibited an increasing number of grains per panicle and grain size, resulting in increase of rice yield. Cytological analysis showed that OsSPL4 could regulate spikelet development by promoting cell division. The results of RNA-seq and qRT-PCR validations also demonstrated that several MADS-box and cell-cycle genes were up-regulated in the mutation lines. Co-expression network revealed that many yield-related genes were involved in the regulation network of OsSPL4. In addition, OsSPL4 could be cleaved by the osa-miR156 in vivo, and the OsmiR156-OsSPL4 module might regulate the grain size in rice. Further analysis indicated that the large-grain allele of OsSPL4 in indica rice might introgress from aus varieties under artificial selection. Taken together, our findings suggested that OsSPL4 could be as a key regulator of grain size by acting on cell division control and provided a strategy for panicle architecture and grain size modification for yield improvement in rice.

With the development of femtosecond (fs) laser technology, an fs laser pulse with 10s of Joule, even 100s of Joule energy is available and the focused laser intensity can be expected to induce the pure Coulomb explosion of the cluster with a much larger average radius than before. Meanwhile, the production of gas cluster with an average radius of upto 10s of nanometer has been possible. In this case, it is necessary to reinvestigate the feasibility of 109 n/shot neutron yield for the practical application in the intense fs laser-driven nuclear fusion. In this work, the neutron yield from the explosions of the D2 clusters of 6–20 nm average radius at the 0.5–100 J pulse energy and the CD4 clusters was investigated theoretically. It is found that the optimum neutron yield of 109 n/shot can be obtained at the laser energy and the cluster radius currently available. However, a clustered-gas jet with a large cross-section is demanded to match the proper plasma diameter.

Microplastic/nanoplastic (MP/NP) pollution has emerged as one of the world's most serious environmental issues, with the potential for grave consequences for ecosystems and human health. This review summarizes the current literature on the impacts of MPs/NPs on higher plants to reveal their phytotoxicity. MPs/NPs can be absorbed into plant roots and then enter and translocate to other tissues by transpirational pull. The interaction between plastic particles and plants not only causes oxidative stress but also induces adverse impacts on photosynthesis, metabolism, genetic expression, and other growth parameters. Furthermore, the combination of MP/NP pollution with other contaminants makes the joint effect more complex. The phytotoxicity of MPs/NPs depends on the characteristics of the plastic particles (exposure dose, size, shape, type, age, and surface charge) and of the plants (species, tissues, and growth stage). The ecotoxicity of MPs/NPs in plant species' surrounding habitats is also discussed. MPs/NPs can alter soil characteristics such as soil structure, water holding capacity, and pH in the rhizosphere. In addition, the rhizosphere microbial community composition and diversity were observed to change in the presence of MPs/NPs. Therefore, MPs/NPs can indirectly affect plant growth by changing the soil properties and the microbial community. In addition, suggestions for future study directions were also given. In summary, this review highlights the potential effects of MPs/NPs on higher plants and the surrounding environment and calls for additional studies to be carried out on the impact of plastic particles on the ecosystem and human health.

Micro(nano)plastics (MNPs) have sparked growing public and scientific concerns as emerging pollutants in recent decades, due to their small size and potential for significant ecological and human health impacts. Understanding the toxicological effects of MNPs on aquatic organisms is of great importance; however, most of the available research on aquatic organisms has focused on the pelagic organisms, and studies on benthic organisms are lacking yet. Being bottom-dwelling creatures, benthos perhaps confronts more extreme pressure from MNPs. Therefore, this review summarizes the current literature on the impacts of MNPs on benthic organisms to reveal their toxicity on the survival, growth, development and reproductive systems. MNPs can accumulate in various tissues of benthos and probably cause tissue-specific damage, resulting in genotoxicity and reproductive toxicity to benthic organisms. And, in severe cases, they may also pass on the adverse effects to the next generations. The complexity of co-exposure to MNPs with other aquatic contaminants is also highlighted. Furthermore, we have comprehensively discussed the internal and external factors affecting the toxicity of MNPs in benthic organisms. Additionally, we also presented the current research gaps and potential future challenges, providing overall background information for a thorough understanding of the toxic effects of MNPs in the benthic aquatic ecosystem.

Background: Transient Ischemic Attack (TIA) (1) is a neurological dysfunction of transient cerebrovascular ischemia, which is more common in clinical practice. The risk of further progression to ischemic stroke after a higher TIA can be used as a strong early warning signal of cerebral infarction. Objectives: To explore the correlation between stromal cell-derived factor 1 (SDF-1) and the prognosis of TIA. Methods: A number of 65 patients with TIA were collected, the ABCD2 clinical risk prediction score was implemented, relevant tests and nuclear magnetic resonance imaging (MRI) were performed, and the SDF-1 was recorded in serum levels. End-point events were selected in patients after cerebral infarction in the short term. The statistical analysis method was used to evaluate TIA short-term development for the occurrence of cerebral infarction after risk, the severity of serum level of SDF-1, and infarction. Results: Based on the results, the high-risk group, middle-risk group, and low-risk group had statistically significant differences in serum SDF-1 levels (F=3.820; P

Microplastics (MPs) are emerging global contaminants, attracting more and more attention because of their difficulty in degradation, extensive and persistent pollution. In freshwater environment, especially in the ocean, they have become a global, public and even political research hotspot. However, the distribution, fate and ecological hazards of MPs in agricultural land and other soils have not been explored fully. Although the occurrence of MPs in different habitats has been reviewed at home and abroad, little attention has been paid to its environmental behavior, ecotoxicology and interaction with biological and chemical pollutants in soil. This review summaries the research progress on the source, accumulation, degradation and migration of MPs in soil, the potential risks of ecological environment and food chain. In order to provide theoretical basis and practical suggestions for related research and regulatory countermeasures, the detection and treatment methods and mechanism of microplastics in soil need to be further explored.

The small size of microplastics and their wide distribution in water environments have attracted worldwide attention and heated discussion, because of their ingestion by aquatic organisms. At present, there are few studies on microplastics pollution in freshwater aquaculture ponds, especially shrimp ponds. In this study, the aquaculture ponds in the Pearl River Estuary were investigated. The abundance and composition of microplastics in different environmental media were studied to explore the potential sources and risk levels of microplastics, so as to provide basic data for the study of microplastics pollution in aquaculture ponds. Microplastics were observed in water and sediment samples at all sampling sites, with the abundance of 6.6 × 103–263.6 × 103 items/m3 (surface water) and 566.67–2500 items/kg (sediment), respectively. Thirty-seven individuals collected in six ponds belong to four species. Microplastics were observed in the gastrointestinal tract (GIT) of all fishes and shrimps, with the abundance ranging from 3–92 items/individual (fish) and 4–21 items/individual (shrimp). Among all samples, microplastics with the size range of &lt, 1 mm and fiber shape were the most common. The main microplastic components were cellulose, polypropylene (PP), and polyethylene (PE). The results of potential risk assessment showed that the pollution investigation of microplastics should not only consider the abundance. Low abundance does not mean low risk. Taking the toxicity score and abundance of microplastics as evaluation indexes to reflect the pollution status of microplastics may make the results more reliable.

Extensive applications of plastic in human life has caused substantial microplastic pollution in the global environment, which, due to plastic's ubiquitous nature and everlasting ecological impact, has caused worldwide concern. In aquatic ecosystems, microplastics are ingested by aquatic animals, affecting their growth and development and resulting in trophic transfer to higher organisms in the food chain. Therefore, consumption of aquatic products is a main primary source of human exposure to microplastics. Recently, aquaculture production has experienced tremendous growth and will exceed production from fish catch soon. Because they constitute an important source of protein in the human food supply, aquaculture products contaminated with microplastics directly affect food quality and safety. The present review summarizes documented studies regarding the occurrence and distribution of microplastics in various aquaculture systems and species and compares microplastic pollution in aquaculture species and captured species. Microplastics in aquaculture environments mainly come from exogenous imports, such as plastic waste and debris from the land, tourism, shipping transportation and atmospheric deposition. In addition, the use of plastic gear and equipment, aquaculture feed and health products, and special aquaculture environments contribute to a higher accumulation of microplastics. We also discuss the adverse effects of microplastics in aquaculture species and the potential health risks of microplastics to humans through the food chain. In summary, this review highlights the effects of microplastic pollution in aquaculture, particularly the ecological impacts on aquaculture species and associated human health implications, and calls for restricted control of microplastics in aquaculture ecosystems.

Scaling operations are widely used in traditional image processing. Therefore, in this paper, an improved quantum image representation based on HSI color space (IQIRHSI) is proposed, which extends the original \(2^{n} \times 2^{n}\) size to general \(2^{{n_{1} }} \times 2^{{n_{2} }}\) size. Then, the quantum algorithms and circuits were designed to implement quantum image scaling. Interpolation was introduced to recover the lost information in the scaled image. The nearest neighbor interpolation method was researched on scaled IQIRHSI to make the interpolation method easy to implement. Finally, the complexity of the quantum circuit for image scaling was analyzed and the process of quantum image scaling was described in detail by examples.

The widespread presence of microplastics in global aquatic ecosystems has aroused growing concern about the potential impacts of microplastics on aquatic biota. In marine and freshwater environments, microplastics are distributed pervasively within water bodies from the upper water column to the bottom layer, making them available to a large variety of aquatic organisms that inhabit different locations. The ingestion of microplastic particles may cause harm to aquatic organisms. Although China's aquatic environments have been seriously polluted by microplastics, the impacts of microplastics on aquatic biota remain to be elucidated. This review summarizes the current state of knowledge about microplastic pollution in aquatic biota in China; specifically, the concentration and characteristics of microplastic particles in aquatic organisms from both seawater and freshwater environments are discussed. The results showed that various aquatic organisms in China have been found to consume microplastics. The average number of microplastic pieces discovered in biota ranged from 0.07 particles to 164 particles per individual in different organisms. The most frequently observed colors of microplastics detected in biota were blue and transparent, and the detected microplastics mainly consisted of fibers. In addition, the impacts of microplastics on aquatic organisms, including physical impacts, chemical impacts, the trophic transfer of microplastics and the potential risks to humans, were discussed. Finally, knowledge gaps were identified in order to guide future studies.

Pectate lyase catalyses the eliminative cleavage of de-esterified pectin, which is a major component of primary cell walls in many higher plants. Pectate lyase-like (PLL) genes have been identified in various plant species and are involved in a broad range of physiological processes associated with pectin degradation. Previous studies have functionally identified two PLL genes in rice (Oryza sativa. L). However, the knowledge concerning genome-wide analysis of this family remains limited, and functions of the other PLL genes have not been thoroughly elucidated to date. In this study, we identified 12 PLL genes based on a genome-wide investigation in rice. A complete overview of this gene family is presented, including chromosomal locations, exon-intron structure, cis-acting elements and conserved motifs. PLL protein sequences from multiple plant species were compared and divided into five groups based on phylogenetic analysis. Quantitative RT-PCR analysis revealed that only a portion of OsPLL genes (4 of 12) exhibits detectable expression levels. Notably, OsPLL1, OsPLL3, OsPLL4 and OsPLL12 exhibit strong and preferential expression in panicles suggesting that the potential roles of these genes are crucial during rice panicle development. Moreover, knockdown of OsPLL3 and OsPLL4 by artificial microRNA (amiRNA) disrupted normal pollen development and resulted in partial male sterility. These results could provide valuable information for characterising the functions and dissecting the molecular mechanisms of the OsPLL genes.

A gas jet produced by adiabatic expansion of gas through a slit nozzle into a vacuum has been served as a target in the study of high harmonic generation or laser wakefield electron acceleration. In this work, Mach–Zehnder interferometry was utilized to obtain the gas density distribution in an argon cluster gas jet produced from a supersonic slit nozzle. The interference fringe distortion caused by the gas jet along the slit width under high backing pressure was recorded and inverted to a gas density profile. The gas backing pressure was up to 80 bars to obtain a gas jet with a higher density. It is found that the gas density in the jet is not uniform along the width direction of the slit nozzle and is the highest at the center of the jet. Along the gas jet, the highest gas density roughly decreases linearly. However, a steep density gradient is observed at P0 = 60–80 bars. Meanwhile, the highest gas density depends linearly on the gas backing pressure and the degree of dependence gradually decreases along the gas jet.

This study evaluates the efficacy of combined chemotherapy for the management of acute promyelocytic leukemia (APL).Literature search was carried out in several electronic databases. Meta-analyses were performed to achieve weighted effect sizes of overall survival (OS), disease-free survival (DFS), complete remission (CR) rate, and relapse rate. Metaregression analyses were performed to evaluate the factors affecting CR and relapse rates.Data from 37 studies (7566 patients) were used for meta-analysis. Median follow-up was 49.24 [95% confidence interval (CI): 41.33, 57.16] months. Five-year OS and DFS were 86.41 [83.97, 88.85] % and 75.42 [67.44, 83.40] %, respectively (pooled effect size [95% CI]). Following induction therapy, 89.77 [87.04, 92.50] % patients achieved CR in 38.25[37.84, 38.65] days and 6.34 [5.98, 6.70] % of the patients died during induction. Induction with all-trans retinoic acid (ATRA), arsenic trioxide (ATO), and daunorubicin (DNR) combination was associated with the highest rate of CR (96.16 [89.92, 92.40] %), followed by ATRA-DNR (94.29 [93.15, 95.43] %), ATRA-DNR-cytarabine (92.04 [88.38, 95.71] %), and ATRA-idarubicin (91.16 [89.92, 92.40] %). Overall relapse rate in the study population was 14.42 [11.97, 16.86] %. Baseline leukocyte count was inversely related to the CR rate.Combined chemotherapy for APL is associated with 90% CR, 14.4% relapse rate, 86% 5-year OS, and 75% 5-year DFS. Induction with ATRA-DNR-ATO is found better than other combinations with respect to CR and relapse rates. Initial leukocyte count may affect prognosis.

Studies of microplastics (MPs) have highlighted their ubiquity in various environments. Recently, microplastics have been observed in atmospheric fallout collected from some cities. Although the studies are limited, some researches have shown that synthetic textiles are main source of airborne microplastics, and fibers are the dominant shape of microplastics in the atmosphere. Due to their small size, airborne microplastics can be directly inhaled posing health risks to humans, particularly to industry workers. Meteorological conditions and human activities affect the distribution and deposition of airborne microplastics. Furthermore, airborne microplastics are contributors to microplastic pollution in aquatic environments. We summarized the current knowledge and provide insights into further research to better understand airborne microplastics and their risks to human.

Long non-coding RNAs (lncRNAs) mediate important epigenetic regulation in various biological processes related to the stress response in plants. However, the systematic analysis of the lncRNAs expressed in Brassica rapa under heat stress has been elusive. In this study, we performed a genome-wide analysis of the lncRNA expression profiles in non-heading Chinese cabbage leaves using strand-specific RNA-sequencing. A total of 4594 putative lncRNAs were identified with a comprehensive landscape of dynamic lncRNA expression networks under heat stress. Co-expression networks of the interactions among the differentially expressed lncRNAs, mRNAs and microRNAs revealed that several phytohormones were associated with heat tolerance, including salicylic acid (SA) and brassinosteroid (BR) pathways. Of particular importance is the discovery of 25 lncRNAs that were highly co-expressed with 10 heat responsive genes. Thirty-nine lncRNAs were predicted as endogenous target mimics (eTMs) for 35 miRNAs, and five of them were validated to be involved in the heat tolerance of Chinese cabbage. Heat responsive lncRNA (TCONS_00048391) is an eTM for bra-miR164a, that could be a sponge for miRNA binding and may be a competing endogenous RNA (ceRNA) for the target gene NAC1 (Bra030820), affecting the expression of bra-miR164a in Chinese cabbage. Thus, these findings provide new insights into the functions of lncRNAs in heat tolerance and highlight a set of candidate lncRNAs for further studies in non-heading Chinese cabbage.

Background Pentatricopeptide-repeat proteins (PPRs) are characterized by tandem arrays of a degenerate 35-amino-acid (PPR motifs), which can bind RNA strands and participate in post-transcription. PPR proteins family is one of the largest families in land plants and play important roles in organelle RNA metabolism and plant development. However, the functions of PPR genes involved in biotic and abiotic stresses of rice (Oryza sativa L.) remain largely unknown. Results In the present study, a comprehensive genome-wide analysis of PPR genes was performed. A total of 491 PPR genes were found in the rice genome, of which 246 PPR genes belong to the P subfamily, and 245 genes belong to the PLS subfamily. Gene structure analysis showed that most PPR genes lack intron. Chromosomal location analysis indicated that PPR genes were widely distributed in all 12 rice chromosomes. Phylogenetic relationship analysis revealed the distinct difference between the P and PLS subfamilies. Many PPR proteins are predicted to target chloroplasts or mitochondria, and a PPR protein (LOC_Os10g34310) was verified to localize in mitochondria. Furthermore, three PPR genes (LOC_Os03g17634,LOC_Os07g40820,LOC_Os04g51350) were verified as corresponding miRNA targets. The expression pattern analysis showed that many PPR genes could be induced under biotic and abiotic stresses. Finally, seven PPR genes were confirmed with their expression patterns under salinity or drought stress. Conclusions We found 491 PPR genes in the rice genome, and our genes structure analysis and syntenic analysis indicated that PPR genes might be derived from amplification by retro-transposition. The expression pattern present here suggested that PPR proteins have crucial roles in response to different abiotic stresses in rice. Taken together, our study provides a comprehensive analysis of the PPR gene family and will facilitate further studies on their roles in rice growth and development. Electronic supplementary material The online version of this article (10.1186/s12864-018-5088-9) contains supplementary material, which is available to authorized users.

Microplastic is an emerging global pollutant that have attracted a great deal of attention from researchers and the public. Guangdong Province has a large population and a relatively well-developed economy, but lacks a modern pollution control system. Guangdong has a long coastline with varying levels of pollution, and little research has been conducted on microplastics. Therefore, we investigated the level of microplastic pollution in coastal areas of Guangdong Province, and the abundance of microplastics in surface waters and sediments at 13 sampling sites. The abundance of microplastics in surface water and sediment samples ranged from 850 to 3500 items/L and 433.3 to 4166.3 items/kg, respectively. Fiber is the main type of microplastics in both surface water and sediment. The sampled microplastics were typically transparent. Raman results show that the surface water sample mainly includes rayon (38.2%), polyethylene terephthalate (16.4%), and ethylene/vinyl acetate copolymer (12.7%). This study used the pollution load index method to evaluate the pollution risk of microplastics along the coast of Guangdong, and provided the basis for the formulation of environmental policy.