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Mitochondrial-associated endoplasmic reticulum (ER) membranes (MAMs) play a key role in several physiological functions, including calcium ion (Ca2+) transfer and autophagy; however, the molecular mechanism controlling this interaction in cadmium (Cd)-induced neurotoxicity is unknown. This study shows that Cd induces alterations in MAMs and mitochondrial Ca2+ levels in PC12 cells and primary neurons. Ablation or silencing of mitofusin 2 (Mfn2) in PC12 cells or primary neurons blocks the colocalization of ER and mitochondria while reducing the efficiency of mitochondrial Ca2+ uptake. Moreover, Mfn2 defects reduce interactions or colocalization between GRP75 and VDAC1. Interestingly, the enhancement of autophagic protein levels, colocalization of LC3 and Lamp2, and GFP-LC3 puncta induced by Cd decreased in Mfn2-/- or Grp75-/- PC12 cells and Mfn2- or Grp75-silenced primary neurons. Notably, the specific Ca2+ uniporter inhibitor RuR blocked both mitochondrial Ca2+ uptake and autophagy induced by Cd. Finally, this study proves that the mechanism by which IP3R-Grp75-VDAC1 tethers in MAMs is associated with the regulation of autophagy by Mfn2 and involves their role in mediating mitochondrial Ca2+ uptake from ER stores. These results give new evidence into the organelle metabolic process by demonstrating that Ca2+ transport between ER-mitochondria is important in autophagosome formation in Cd-induced neurodegeneration.
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Cádmio , Cálcio , Retículo Endoplasmático , Animais , Autofagia , Cádmio/metabolismo , Cádmio/toxicidade , Cálcio/metabolismo , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Neurônios/metabolismo , RatosRESUMO
Phospholipase C zeta1 (Plcz1) was known to be a physiological factor in sperm that activates oocytes to complete meiosis by triggering Ca2+ oscillations after fertilisation. However, the role of male Plcz1 in spermatogenesis and early embryo development in progeny has been controversial. Plcz1 knockout (Plcz1-/-) mouse model (Plcz1m3 and Plcz1m5) was generated by using the CRISPR-Cas9 system. The fertility of Plcz1-/- mice was evaluated by analysing the number of offsprings, sperm quality, pathological changes in the testis and epididymis. RNA-seq and RT-PCR were performed to screen differentially expressed genes and signalling pathways related to fertility in Plcz1-/- mice. Further mechanism was explored by using Plcz1-/- cells. Plcz1 knockout led to hypofertility in male mice. In particular, a significant time delay in development and polyspermy was found in eggs fertilized by both Plcz1m3 and Plcz1m5 sperm. Interestingly, a decline in sperm quality combined with pathological changes in epididymis was found in Plcz1m3 mice but not in Plcz1m5 mice. Notably, abnormal cytoskeleton appears in epididymis of Plcz1m3 mice and Plcz1-/- cells. Cytoskeleton damage of epididymis is involved in fertility decline of males upon Plcz1 deficiency in this model.
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Epididimo , Fosfolipases Tipo C , Animais , Masculino , Camundongos , Citoesqueleto/metabolismo , Epididimo/metabolismo , Fertilidade/genética , Camundongos Knockout , Fosfoinositídeo Fosfolipase C/genética , Fosfoinositídeo Fosfolipase C/metabolismo , Sêmen/metabolismo , Espermatogênese/genética , Espermatozoides/metabolismo , Testículo/metabolismo , Fosfolipases Tipo C/metabolismoRESUMO
Controlling the morphology of highly homogeneous nanoribbons is one of the main goals for synthesizing catalysts with excellent activity and durability. In this Communication, platinum (Pt) nanoribbons were synthesized by a one-pot method. We used ammonium fluoride (NH4F) as the regulator, under 8 atm of hydrogen (H2), to synthesize zigzag-shaped two-dimensional Pt nanoribbons. Benefiting from their unique morphology, the Pt nanoribbons display superior electrocatalytic activity and stability.
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OBJECTIVE: To identify pathological mutation of D4Z4 in a child with facioscapulohumeral muscular dystrophy (FSHD) presented initially as mental retardation. METHODS: Wechsler Intelligence Scale for Children Revised in China (WISC-IV) was used to assess the patient's IQ. Other clinical data was also collected. With genomic DNA extracted from peripheral blood samples, the child and his parents were subjected to medical exome sequencing and copy number variation analysis by next generation sequencing (NGS). The D4Z4 repeats and their origin source were determined by molecular combing. RESULTS: By the WISC-IV test, the child was found to have a total IQ of 41, with a speech comprehension IQ of 45, and perceptual inference index IQ of 52. No pathological mutation was detected by NGS. By molecular combing method, the child was found to carry a D4Z4 spanning 5.2 kb with a copy number of 2. Analysis of his parents indicate that the mutation was de novo. CONCLUSION: The D4Z4 copy number variation may account for the FSHD and mental retardation in the child. The molecular combing method can be used to identify the number of repeat units and facilitate the diagnosis of FSHD.
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Deficiência Intelectual , Distrofia Muscular Facioescapuloumeral , Criança , China , Cromossomos Humanos Par 4 , Variações do Número de Cópias de DNA , Humanos , Deficiência Intelectual/genética , Distrofia Muscular Facioescapuloumeral/genética , MutaçãoRESUMO
BACKGROUND: Intellectual disability/developmental delay is a complex condition with extraordinary heterogeneity. A large proportion of patients lacks a specific diagnosis. Next generation sequencing, enabling identification of genetic variations in multiple genes, has become an efficient strategy for genetic analysis in intellectual disability/developmental delay. METHODS: Clinical data of 112 Chinese families with unexplained intellectual disability/developmental delay was collected. Targeted next generation sequencing of 454 genes related to intellectual disability/developmental delay was performed for all 112 index patients. Patients with promising variants and their other family members underwent Sanger sequencing to validate the authenticity and segregation of the variants. RESULTS: Fourteen promising variants in genes EFNB1, MECP2, ATRX, NAA10, ANKRD11, DHCR7, LAMA1, NFIX, UBE3A, ARID1B and PTPRD were identified in 11 of 112 patients (11/112, 9.82%). Of 14 variants, eight arose de novo, and 13 are novel. Nine patients (9/112, 8.03%) got definite molecular diagnoses. It is the first time to report variants in EFNB1, NAA10, DHCR7, LAMA1 and NFIX in Chinese intellectual disability/developmental delay patients and first report about variants in NAA10 and LAMA1 in affected individuals of Asian ancestry. CONCLUSIONS: Targeted next generation sequencing of 454 genes is an effective test strategy for patients with unexplained intellectual disability/developmental delay. Genetic heterogenicity is significant in this Chinese cohort and de novo variants play an important role in the diagnosis. Findings of this study further delineate the corresponding phenotypes, expand the mutation spectrum and support the involvement of PTPRD in the disease.
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Deficiências do Desenvolvimento/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Deficiência Intelectual/genética , Mutação , Adolescente , Criança , Pré-Escolar , China , Cromossomos Humanos X , Feminino , Genes Dominantes , Genes Recessivos , Heterogeneidade Genética , Humanos , Lactente , Masculino , Linhagem , FenótipoRESUMO
The wetting behavior of hierarchically wrinkled surfaces has attracted great interest because of its broad application in flexible electronic, microfluidic chip, and biomedicine. However, theoretical studies concerning the relationship between the apparent contact angle and mechanical strain applied on the soft and flexible surface with a hierarchically wrinkled structure are still limited. We established a theoretical framework to describe and understand how prestrain and applied dynamic strain reversibly tune the wettability of the hierarchically wrinkled surface. More specifically, a direct relationship between the mechanical strain and contact angle was built through reversible tuning of the amplitude and the wavelength of the wrinkled structures caused by mechanical strain, which allowed for more precise adjustment of surface wettability. To verify the accuracy of the theoretical relationship between the contact angle and mechanical strain, a soft surface with a hierarchically wrinkled structure was prepared by combining wrinkled microstructures and strip ones. The results showed that the experimental contact angles were in agreement with the theoretical ones within a limited error range. This will be helpful for further investigation on the wettability of hierarchically wrinkled surfaces.
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BACKGROUND: X-linked agammaglobulinaemia (XLA) is a rare inherited primary immunodeficiency disease characterized by the B cell developmental defect, caused by mutations in the gene coding for Bruton's tyrosine kinase (BTK), which may cause serious recurrent infections. The diagnosis of XLA is sometimes challenging because a few number of patients have higher levels of serum immunoglobulins than expected. In this study, we reported an atypical case with recurrent meningitis, delayed diagnosis with XLA by genetic analysis at the second episode of meningitis at the age of 8 years. CASE REPORT: An 8-year-old Chinese boy presented with fever, dizziness and recurrent vomiting for 3 days. The cerebrospinal fluid (CSF) and magnetic resonance imaging (MRI) results were suggestive of bacterial meningoencephalitis, despite the negative gram staining and cultures of the CSF. The patient was treated with broad-spectrum antibiotics and responded well to the treatment. He had history of another episode of acute pneumococci meningitis 4 years before. The respective level of Immunoglobulin G (IgG), Immunoglobulin A (IgA) and Immunoglobulin M (IgM) was 4.85 g/L, 0.93 g/L and 0.1 g/L at 1st episode, whereas 1.9 g/L, 0.27 g/L and 0 g/L at second episode. The B lymphocytes were 0.21 and 0.06% of peripheral blood lymphocytes at first and second episode respectively. Sequencing of the BTK coding regions showed that the patient had a point mutation in the intron 14, hemizyous c.1349 + 5G > A, while his mother had a heterozygous mutation. It was a splice site mutation predicted to lead to exon skipping and cause a truncated BTK protein. CONCLUSION: Immunity function should be routinely checked in patients with severe intracranial bacterial infection. Absence of B cells even with normal level of serum immunoglobulin suggests the possibility of XLA, although this happens only in rare instances. Mutational analysis of BTK gene is crucial for accurate diagnosis to atypical patients with XLA.
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Agamaglobulinemia/complicações , Agamaglobulinemia/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/complicações , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Encefalite Infecciosa/genética , Tirosina Quinase da Agamaglobulinemia/genética , Agamaglobulinemia/genética , Criança , Análise Mutacional de DNA , Diagnóstico Tardio , Doenças Genéticas Ligadas ao Cromossomo X/genética , Humanos , Masculino , MutaçãoRESUMO
The wetting transition on submersed superhydrophobic surfaces with hierarchical structures and the influence of trapped air on superhydrophobic stability are predicted based on the thermodynamics and mechanical analyses. The dewetting transition on the hierarchically structured surfaces is investigated, and two necessary thermodynamic conditions and a mechanical balance condition for dewetting transition are proposed. The corresponding thermodynamic phase diagram of reversible transition and the critical reversed pressure well explain the experimental results reported previously. Our theory provides a useful guideline for precise controlling of breaking down and recovering of superhydrophobicity by designing superhydrophobic surfaces with hierarchical structures under water.
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Highly adherent wettability patterns on the substrate-independent superhydrophobic surfaces of trimethoxyoctadecylsilane modified titanium dioxide (TiO2)-based coatings were prepared by using commercial photolithography. Three custom unidirectional channels with gradient wettability patterns were obtained by spatially selective wettability conversion from superhydrophobic to superhydrophilic when the coatings were exposed to ultraviolet light (â¼365 nm). The movement behavior of droplets on these unidirectional channels was studied and the displacement of droplet movement was effectively controlled. Integrating the idea of gradient wettability patterns into planar microfluidic devices (microreactors), a self-driven fluid transport was achieved to realize droplet metering, merging or reaction, and rapid transport. This self-driven fluid transport with gradient wettability patterns has great potential in fabricating a new category of pump-free microfluidic systems that can be used in various conditions.
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Menkes disease (MD) is a fatal X-linked multisystem disease caused by mutations in ATP7A. In this study, clinical and genetic analysis was performed in 24 male MD patients. Development delay, seizures, kinky coarse hair, and dystonia were found in 24, 22, 24, and 24 patients, respectively. Serum ceruloplasmin/copper tested in 19 patients was low. Abnormal classic features of MD presented in the MRI/MRA of 19 patients. Seventeen mutations of ATP7A were identified in 22 patients. Twelve were novel mutations including three small deletion/insertion, one missense mutation, two nonsense mutations, three splicing-site mutations, and three gross deletions. Twenty-two patients were genetically diagnosed; neither point mutation nor deletion/duplication was found in two of them. c.2179G > A found in five patients might be a hot-spot mutation. Prenatal molecular diagnosis was performed for five unrelated fetuses (1 female and 4 male), which found four fetuses to be wild type and one male carried the same mutation as the proband. This study of the largest sample of Chinese MD patients examined to date discovered the unique phenotype and genotype spectrum in Chinese patients with 12 novel mutations of ATP7A, and that c.2179G > A might be a hot-spot mutation in MD patients. Five successful prenatal diagnosis contributed important information for MD families.
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ATPases Transportadoras de Cobre/genética , Síndrome dos Cabelos Torcidos/diagnóstico , Mutação , China , Feminino , Testes Genéticos , Humanos , Masculino , Síndrome dos Cabelos Torcidos/genética , Gravidez , Diagnóstico Pré-NatalRESUMO
The mechanisms involved in the fast growth of Angiostrongylus cantonensis from fifth-stage larvae (L5) to female adults and how L5 breaks through the blood-brain barrier in a permissive host remain unclear. In this work, we compared the transcriptomes of these two life stages to identify the main factors involved in the rapid growth and transition to adulthood. RNA samples from the two stages were sequenced and assembled de novo. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses of 1,346 differentially expressed genes between L5 and female adults was then undertaken. Based on a combination of analytical results and developmental characteristics, we suggest that A. cantonensis synthesizes a large amount of cuticle in L5 to allow body dilatation in the rapid growth period. Products that are degraded via the lysosomal pathway may provide sufficient raw materials for cuticle production. In addition, metallopeptidases may play a key role in parasite penetration of the blood-brain barrier during migration from the brain. Overall, these results indicate that the profiles of each transcriptome are tailored to the need for survival in each developmental stage.
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BACKGROUND: Ferulic acid (FA) and p-coumaric acid (PCA) are widely distributed in graminaceous plant cell walls. This study investigated the in vitro and in vivo digestibility of ester-linked FA (FAest) and PCA (PCAest) in lactating dairy cows. RESULTS: Regarding corn stover, ensiled corn stover, whole corn silage, Chinese wild ryegrass and alfalfa hay with different phenolic acid profiles, the in vitro rumen digestibility of forage FAest and PCAest was negatively correlated with the ether-linked FA content and original PCA/FA ratio in the forages. The concentration of both phenolic acids in culture fluids was low after a 72 h incubation, and the mixed rumen microorganisms metabolized nearly all phenolic acids released into the culture fluids. FAest digestibility in the whole digestive tract was negatively correlated with dietary PCA/FA ratio, but a converse result occurred with dietary PCAest digestibility. The digestibility in either the rumen or the whole digestive tract was greater for FAest than for PCAest. CONCLUSION: Forage PCAest in comparison with FAest is not easily digested in either the rumen or the whole digestive tract, and they were negatively affected by forage FAeth content and lignification extent indicated by the original dietary PCA/FA ratio.
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Bactérias/metabolismo , Bovinos/metabolismo , Ácidos Cumáricos/metabolismo , Digestão , Rúmen/microbiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Feminino , Lactação/fisiologia , Lolium/química , Medicago sativa/química , Propionatos , Silagem , Zea mays/químicaRESUMO
Although Apostichopus japonicus is recognized as a food and drug resource with significant immunomodulatory activity, its role in regulating the mucosal immunity remains unclear. This study aimed to explore the effects of dietary A. japonicus on mucosal immunity with an immunosuppressive mouse model. The expression of lysozyme, secretory immunoglobulin A(sIgA), and immunoglobulin A(IgA) as well as polymeric immunoglobulin receptor(pIgR) in respiratory and intestine organs was investigated. The results showed that A. japonicus could improve both the systematic and mucosal immunity. The expression of lysozyme, sIgA, and IgA in the respiratory organ was increased more significantly. Consumption of A. japonicus with the dose of 512 mg kg(-1), which equals to (1)/2 sea cucumber per day for adults, showed better effects. This study elucidated positive effects of A. japonicus on mucosal immunity for the first time, suggesting that moderate consumption of A. japonicus is helpful in improving mucosal immunity and preventing exogenous infection.
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Dieta , Imunidade nas Mucosas/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Terapia de Imunossupressão , Intestinos/imunologia , Sistema Respiratório/imunologia , Stichopus/química , Animais , Relação Dose-Resposta a Droga , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/imunologia , Imunoglobulina A Secretora/metabolismo , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Muramidase/metabolismo , Especificidade de Órgãos , Receptores de Imunoglobulina Polimérica/metabolismo , Sistema Respiratório/efeitos dos fármacos , Sistema Respiratório/metabolismoRESUMO
BACKGROUND: We aimed to delineate the genotype and phenotype of patients with KCNQ2 mutations from South China. METHODS: Clinical manifestations and characteristics of KCNQ2 mutations of patients from South China were analyzed. Previous patients with mutations detected in this study were reviewed. RESULTS: Eighteen epilepsy patients with KCNQ2 mutations, including seven self-limited neonatal epilepsy (SeLNE), two self-limited infantile epilepsy (SeLIE) and nine developmental and epileptic encephalopathy (DEE) were enrolled. The age of onset (p=0.006), mutation types (p=0.029), hypertonia (p=0.000), and seizure offset (p=0.029) were different in self-limited epilepsy (SeLE) and DEE. De novo mutations were mainly detected in DEE patients (p=0.026). The mutation position, EEG or the age of onset were not predictive for the seizure or ID/DD outcome in DEE, while the development of patients free of seizures was better than that of patients with seizures (p=0.008). Sodium channel blockers were the most effective anti-seizure medication, while the age of starting sodium channel blockers did not affect the seizure or development offset. We first discovered the seizure recurrence ratio in SeLNE/SeLIE was 23.1% in South China. Four novel mutations (c.790T>C, c.355_363delGAGAAGAG, c.296+2T>G, 20q13.33del) were discovered. Each of eight mutations (c.1918delC, c.1678C>T, c.683A>G, c.833T>C, c.868G>A, c.638G>A, c.997C>T, c.830C>T) only resulted in SeLE or DEE, while heterogeneity was also found. Six patients in this study have enriched the known phenotype caused by the mutations (c.365C>T, c.1A>G, c.683A>G, c.833T>C, c.830C>T, c.1678C>T). CONCLUSION: This research has expanded known phenotype and genotype of KCNQ2-related epilepsy, and the different clinical features of SeLE and DEE from South China.
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Canal de Potássio KCNQ2 , Mutação , Fenótipo , Humanos , Canal de Potássio KCNQ2/genética , China/epidemiologia , Feminino , Masculino , Lactente , Pré-Escolar , Genótipo , Criança , Recém-Nascido , Epilepsia/genética , Epilepsia/tratamento farmacológico , Testes Genéticos/métodosRESUMO
BACKGROUND: The natural history and genotype-phenotype correlation of Pelizaeus-Merzbacher disease (PMD) of Chinese patients has been rarely reported. METHOD: Patients who met the criteria for PMD were enrolled in our study. Genomic analysis was conducted by multiplex ligation probe amplification (MLPA) and Sanger or whole-exome sequencing (WES). Natural history differences and genotype-phenotype correlations were analyzed. RESULT: A total of 111 patients were enrolled in our follow-up study. The median follow-up interval was 53 m (1185). Among PMD patients, developmental delay was the most common sign, and nystagmus and hypotonia were the most common initial symptoms observed. A total of 78.4% of the patients were able to control their head, and 72.1% could speak words. However, few of the patients could stand (9.0%) or walk (4.5%) by themselves. Nystagmus improved in more than half of the patients, and hypotonia sometimes deteriorated to movement disorders. More PLP1 point mutations patients were categorized into severe group, while more patients with PLP1 duplications were categorized into mild group (p < 0.001). Compared to patients in mild groups, those in the severe group had earlier disease onset and had acquired fewer skills at a later age. CONCLUSION: PMD patients have early disease onset with nystagmus and hypotonia followed by decreased nystagmus and movement disorders, such as spasticit. Patients with PLP1 duplication were more likely to be categorized into the mild group, whereas patients with point mutations were more likely to be categorized into the severe group.
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Doença de Pelizaeus-Merzbacher , China , Seguimentos , Estudos de Associação Genética , Humanos , Proteína Proteolipídica de Mielina/genética , Doença de Pelizaeus-Merzbacher/diagnóstico , Doença de Pelizaeus-Merzbacher/genéticaRESUMO
Chimonobambusa sichuanensis is an ornamental shrubby bamboo endemic to southern China. In this study, the complete chloroplast genome (cpDNA) sequence of Chimonobambusa sichuanensis was first reported. The cpDNA is 139,594 bp in length, including a small single-copy (SSC) region of 12,820 bp and a large single-copy (LSC) region of 83,196 bp, which were separated by a pair of inverted repeat (IR) regions of 21,789 bp. The genome contains 140 genes, consisting of 93 protein-coding genes, seven ribosomal RNA (rRNA) genes, and 40 transfer RNA (tRNA) genes. The phylogenetic analysis showed that C. sichuanensis is highly clustered in the Phyllostachys clade, sister to C. tumidissinoda.
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To understand the effects of straw return modes on soil carbon pools, we investigated total soil organic carbon (SOC), labile organic carbon fractions, and inorganic carbon (SIC) in different straw return modes at a depth of 0-40 cm under a maize-wheat cropping system in the Guanzhong Plain, Shaanxi, based on an 11-year field experiment. There were five straw return modes, i.e., no return of straw of both wheat and maize (CK), the retention of high wheat stubble plus the return of chopped maize straw (WH-MC), the return of both chopped wheat and maize straw (WC-MC), the retention of high wheat stubble and no return of maize straw (WH-MN), and the return of chopped wheat straw and no return of maize straw (WC-MN). The proportions of SOC storage were significantly higher under the WH-MC and WC-MC treatments than that under the CK by 28.1% and 22.2%, respectively. The proportions of SIC storage were increased by 20.4% and 17.3%, respectively. Compared with the initial value, the increases of sequestered SOC and SIC ranged from -0.84 t·hm-2 to 6.55 t·hm-2, respectively, and from -0.26 t·hm-2 to 8.61 t·hm-2, respectively. The efficiency of sequestration of SOC was 7.5%. To maintain the basic SOC level, the minimum carbon input from straw was 4.65 t·hm-2·a-1. The contents of labile carbon fractions at the 0-20 cm layer increased significantly under the WH-MC and WC-MC treatments compared with those of the control. Results of principal component analysis showed that the changes in soil carbon pools were primarily affected by the amount of straw return. Additionally, the increases in SIC storage could be ascribed to the Ca2+ and Mg2+ ions derived from irrigation water and plant residues that could coprecipitate with the CO2 from SOC mineralization to form CaCO3. In conclusion, our results indicated that the straw return mode that utilized the retention of high wheat stubble and chopped maize straw was sufficient to maintain soil carbon storage and would be the optimal straw-returning strategy for the region.
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Solo , Triticum , Agricultura , Carbono/análise , China , Zea maysRESUMO
Flatheads are valuable commercial fish species endemic to the Indo-West Pacific. Due to their economic value and unique biological traits, such as metamorphosis and camouflage, they serve as ideal marine organisms for studies on demersal adaptation and evolution. The brown-spotted flathead (Platycephalus sp.1) is the most widely distributed in the northwestern Pacific. Despite the lack of a valid scientific name, it has been long recognized and exploited in the marine fisheries of China, Japan, and Korea. In the current study, we applied Illumina, PacBio, and Hi-C sequencing to assemble a chromosome-scale genome for this species. The assembled genome was 660.63 Mb long with a scaffold N50 of 28.65 Mb and 100% of the contigs were anchored onto 24 chromosomes. We predicted 22 743 protein-coding genes, 94.8% of which were functionally annotated. Comparative genomic analyses suggested that Platycephalus sp.1 diverged from its common ancestor with Gasterosteus aculeatus ~88.4 million years ago. The expanded gene families were significantly enriched in immune, biosynthetic, and metabolic pathways. Furthermore, three shared Gene Ontology terms and 377 common positively selected genes were identified between flathead and flatfish species, suggesting that these genes may contribute to demersal adaptation in flatheads. The assembled genomic data provide a valuable molecular resource for further research on the biological and adaptive evolution of flathead species.
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Adaptação Fisiológica/genética , Cromossomos/genética , Peixes/genética , Genoma , Genômica/métodos , Animais , Oceano Pacífico , FilogeniaRESUMO
Developing the highly efficient and low-cost electrocatalysts for the oxygen evolution reactions (OERs), as vital half reactions of water splitting, is crucial for renewable energy technology. The electrocatalysts based on multi-component and hierarchically structured non-noble metal hydr(oxy)oxide materials are of great prospects. Herein, we report an efficient strategy at low temperatures for synthesizing amorphous iron-doped cobalt-molybdenum ultrathin hydroxide (Fe-CoMo UH) nanosheets. Benefiting from the ultrathin amorphous structure and multi-metal coordination, Fe-CoMo UH nanosheets exhibit outstanding performance for OERs with a low overpotential of 245 mV at 10 mA cm-2, a small Tafel slope of 37 mV dec-1 and an excellent stability for 90 h. The mass activity of Fe-CoMo UH is higher than that of commercial Ir/C and most of the transition metal hydroxide catalysts. This work provides a feasible consideration for the construction of promising efficient non-noble metal catalysts.
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The porous polymer matrix with good stability and confined microenvironment is considered as ideal support to stabilize isolated metal centers for catalysis. Herein, we report a "one-pot" method to prepare a kind of palladium complexed with azo porous organic polymer nanospheres (Pd-azo-POPs). The method combines the synthesis of azo-POPs with the reduction of the Pd ion, where azo serves as an anchoring group to limit the growth of Pd. The unique structure is conductive to the formation of a uniform active center and provides improved electron transfer. Pd-azo-POPs-80 exhibits a high catalytic activity and cycling stability both in 4-nitrophenol reduction and Suzuki-Miyaura coupling. The knor for the 4-nitrophenol reduction was 174.7â min-1 mM-1 and the conversion remains above 90% after 6â cycles. Meanwhile, the yield was still up to 94.5% after 5â cycles for the Suzuki-Miyaura coupling reaction of benzene derivatives with I/Br under mild conditions.