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1.
J Environ Manage ; 355: 120251, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38422844

RESUMO

Drought synchronously affects the water cycle and interferes with the carbon cycle in terrestrial ecosystems. Ecosystem water use efficiency (WUE), serving as a vital metric for assessing the interplay between water and carbon cycles, has found extensively use in exploring how ecosystems responses to drought. However, the effects of soil moisture drought on WUE are still poorly recognized. Taking Ziya River Basin as an example, the spatial-temporal variations of WUE from 2001 to 2020 were estimated by the Penman-Monteith-Leuning Version 2 (PML-V2) data. Based on the Standardized Soil Moisture Index (SSI) calculated from Soil Moisture of China by in situ data, version 1.0 (SMCI1.0) data, the sensitivity and thresholds of different vegetation WUE to drought magnitudes were investigated, and the influences of both lagged and cumulative effects of drought on WUE were further analyzed. Results showed that the annual mean WUE was 2.160 ± 0.975 g C kg-1 H2O-1 in the Ziya River Basin, with a significant increasing trend of 0.037 g C kg-1 H2O-1 yr-1 (p < 0.05). For all the vegetation types, the WUE reached the maximum value at a certain drought threshold (SSI = -1.5 ± 0.1). The dominant factor controlling WUE sensitivity to drought changed from evapotranspiration (ET) to gross primary production (GPP) when severe drought transformed into extreme drought. Significant lagged and cumulative effects were found in the response of WUE to drought in nearly 58.64 % (72.94 %) of the study area, with an average time scale of 6.65 and 2.11 months (p < 0.05) respectively. Drought resistance in descending order was: forest > shrub > grassland > cropland. Our findings enrich the understanding of the coupled carbon and water cycle processes in terrestrial ecosystems and their response to soil moisture drought in the context of global climate change.


Assuntos
Ecossistema , Solo , Secas , Água , China
2.
J Environ Manage ; 334: 117442, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36773451

RESUMO

Urban flooding and waterlogging are becoming increasingly serious due to rapid urbanization and climate change. The stormwater management philosophy of low-impact development (LID) has been applied in urban construction to alleviate these problems. The selection and placement of LID designs are the most important tasks. In this study, LID experiments were performed to calibrate the Storm Water Management Model (SWMM). Then, a multi-objective optimization model, which adopted the minimum surface runoff coefficient, surcharge time, and investment cost as objectives, was established by coupling the SWMM and non-dominated sorting genetic algorithm-II (NSGA-II). Hydrological simulations were performed with the SWMM, and optimal calculations were conducted with NSGA-II. Real-coded optimal variables containing detailed size and location information of multiple LID measures were generated, and a decision space for LID design selection was obtained. The optimization designs reduced the surface runoff coefficient from 0.7 to approximately 0.5, the conduit surcharge duration was reduced from 1.62 h to 0.04-0.47 h, and the total investment cost only ranged from 395,000-872,000 ¥. Thus, the optimization model could achieve synchronous optimization of all objectives. This study could provide valuable information for LID design with the aim of urban flooding and waterlogging control.


Assuntos
Chuva , Água , Urbanização , Hidrologia , China , Movimentos da Água , Modelos Teóricos
3.
Adv Mater ; 35(9): e2209886, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36515180

RESUMO

Zn powder (Zn-P)-based anodes are always regarded as ideal anode candidates for zinc ion batteries owing to their low cost and ease of processing. However, the intrinsic negative properties of Zn-P-based anodes such as easy corrosion and uncontrolled dendrite growth have limited their further applications. Herein, a novel 3D cold-trap environment printing (3DCEP) technology is proposed to achieve the MXene and Zn-P (3DCEP-MXene/Zn-P) anode with highly ordered arrangement. Benefitting from the unique inhibition mechanism of high lattice matching and physical confinement effects within the 3DCEP-MXene/Zn-P anode, it can effectively homogenize the Zn2+ flux and alleviate the Zn deposition rate of the 3DCEP-MXene/Zn-P anode during Zn plating-stripping. Consequently, the 3DCEP-MXene/Zn-P anode exhibits a superior cycling lifespan of 1400 h with high coulombic efficiency of ≈9.2% in symmetric batteries. More encouragingly, paired with MXene and Co doped MnHCF cathode via 3D cold-trap environment printing (3 DCEP-MXene/Co-MnHCF), the 3DCEP-MXene/Zn-P//3DCEP-MXene/Co-MnHCF full battery delivers high cyclic durability with the capacity retention of 95.7% after 1600 cycles. This study brings an inspired universal pathway to rapidly fabricate a reversible Zn anode with highly ordered arrangement in a cold environment for micro-zinc storage systems.

4.
Ying Yong Sheng Tai Xue Bao ; 34(12): 3195-3202, 2023 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-38511357

RESUMO

To clarify ecological environment quality and its influencing factors, we constructed an improved remote sensing ecological index (ISREI) coupled with greenness, humidity, dryness and aerosol optical depth based on satellite remote sensing data. We evaluated the ecological environment quality of Luanhe River Basin by IRSEI, and investigated the influencing factors. The results showed that IRSEI were 0.488, 0.532, 0.563, and 0.586 in 2000, 2008, 2016, and 2022, respectively, indicating that ecological environment quality of the basin continued to rise. The ecological environment quality and its change were characterized by high in southeast and low in northwest, improvement in southeast and degradation in northwest. Annual precipitation, slope, land use, primary industry and tertiary industry were the key factors affecting the spatial variations of ecological environment quality. The interaction of these factors had a more significant impact on the ecological environment quality.


Assuntos
Tecnologia de Sensoriamento Remoto , Rios , Monitoramento Ambiental/métodos , China , Umidade , Ecossistema
5.
ACS Appl Mater Interfaces ; 14(48): 54034-54043, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36383043

RESUMO

In this work, we demonstrate the performance of a silicon-compatible, high-performance, and self-powered photodetector. A wide detection range from visible (405 nm) to near-infrared (1550 nm) light was enabled by the vertical p-n heterojunction between the p-type antimony telluride (Sb2Te3) thin film and the n-type silicon (Si) substrates. A Sb2Te3 film with a good crystal quality, low density of extended defects, proper stoichiometry, p-type nature, and excellent uniformity across a 4 in. wafer was achieved by atomic layer deposition at 80 °C using (Et3Si)2Te and SbCl3 as precursors. The processed photodetectors have a low dark current (∼20 pA), a high responsivity of (∼4.3 A/W at 405 nm and ∼150 mA/W at 1550 nm), a peak detectivity of ∼1.65 × 1014 Jones, and a quick rise time of ∼98 µs under zero bias voltage. Density functional theory calculations reveal a narrow, near-direct, type-II band gap at the heterointerface that supports a strong built-in electric field leading to efficient separation of the photogenerated carriers. The devices have long-term air stability and efficient switching behavior even at elevated temperatures. These high-performance and self-powered p-Sb2Te3/n-Si heterojunction photodetectors have immense potential to become reliable technological building blocks for a plethora of innovative applications in next-generation optoelectronics, silicon-photonics, chip-level sensing, and detection.

6.
Ying Yong Sheng Tai Xue Bao ; 33(3): 801-807, 2022 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-35524534

RESUMO

Drought is one of the main disasters causing agricultural production losses. Accurate and effective agricultural drought monitoring is of great significance to reduce agricultural production losses. In this study, the standardized soil moisture index for agricultural drought evaluation was established by using the historical time series of soil moisture. Based on the index, the temporal and spatial distribution of drought events in the Luanhe River Basin from 2002 to 2019 were analyzed, and the agricultural drought was quantitatively evaluated. The results showed that soil moisture of most grid units in the Luanhe River Basin obeyed normal distribution during the study period, and that the soil moisture of a few grid units obeyed generalized extreme distribution. The changes of drought and flood in each grid unit had good temporal consistency, that is, the changes of drought and flood was consistent. The changes of drought and flood in the middle of the basin was relatively significant, while the agricultural drought generally showed a trend of reduction. The spatial distribution of agricultural drought severity was not obvious. Relatively speaking, the drought characteristics (the frequency, duration and intensity of drought) were higher in the middle and northwest of the basin and lower in the southeast. The results could provide a reference for agricultural drought prediction and the formulation of drought prevention and mitigation measures in the Luanhe River Basin.


Assuntos
Secas , Rios , Agricultura , Inundações , Solo
7.
Sci Total Environ ; 699: 134278, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33736192

RESUMO

The aim of this paper is to propose a new non-stationarity hydrological drought index, which incorporates the climate-driven and human-induced non-stationarities in streamflow. For this purpose, significant teleconnection indices have been selected by correlation analysis to represent large-scale climate variability, and human-induced indices have been calculated using the Soil and Water Assessment Tool (SWAT) to indicate varying anthropogenic forcing. Whereafter, a non-stationary probability model fitted to streamflow series has been developed using the climate-driven and human-induced indices as covariates. Base on the non-stationary model, we present a variation of the classical Standardized Streamflow Index (SSI), named Non-stationary Standardized Streamflow Index (NSSI). Focusing on the streamflow records of Luanhe River basin from 1958 to 2011, a comparison of performance between NSSI and SSI has been conducted to demonstrate the capability of the NSSI. Finally temporal-spatial patterns of drought during the last 40 years over the basin have been estimated by using the NSSI. The results show that the non-stationary model describes the variability of streamflow better than a stationary one, and the covariates selected with Akaike information criterion (AIC) provide insights into non-stationary behaviors. Since the NSSI effectively accounts for the non-stationarities of streamflow associated with climate changes and human activities, it provides more reasonable and satisfactory results than the SSI. Additionally, it is indicated that serious long-term droughts generally appeared more frequently in the southeast of Luanhe River basin, and an obvious aggravating tendency of drought was observed in this area during 1971-2011. The presented NSSI enables hydrological droughts to be better characterized in a non-stationary context, thus providing valuable references for the improvement of drought index and the drought related policy-making.

8.
Inorg Chem ; 57(12): 7121-7128, 2018 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-29851482

RESUMO

Ba1+ xMoO4 (-0.03 ≤ x ≤ 0.03) ceramics were fabricated by a conventional two-step sintering technique. X-ray diffraction patterns show that there appeared new diffraction peaks when x > 0, which were identified as Ba2MoO5. The Rietveld refinement results indicate that the unit cell volume is the largest at x = -0.02, because it has the lowest packing fraction and covalency. The far-infrared reflectivity (IR) spectra were fitted and analyzed for calculating the intrinsic properties, which comply well with the data obtained from microscopic polarizabilities and damping coefficient angle. The proportion of each mode in the dielectric response demonstrates that the Ba-O8 polyhedra have a decisive role on the dielectric properties. And based on the Raman modes, the internal relations of the structural-properties were revealed with the changes of Ba2+ content.

9.
Sci Rep ; 7(1): 13336, 2017 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-29042593

RESUMO

Pr(Mg1/2Sn1/2)O3 (PMS) ceramic was prepared through a conventional solid-state reaction method. Crystal structure was investigated through X-ray diffraction (XRD), which certificates that the main phase is PMS with monoclinic P2 1/n1 symmetry. Lattice vibrational modes were obtained through Raman scattering spectroscopy and Fourier transform far-infrared reflection spectroscopy. The Raman spectrum active modes were assigned and illustrated, respectively, and then fitted with Lorentzian function. The four modes within the range of 110-200 cm-1 are derived from the F 2g vibrations (A-site cations), and the other three modes (300-430 cm-1) are derived from the F 2g vibrations (B-site cations).The mode with highest frequency above 650 cm-1 is attributed to A 1g -like mode that corresponds to the symmetric breathing of oxygen octahedral. The far-infrared spectrum with seven infrared active modes was fitted using four-parameter semi-quantum models to calculate intrinsic properties (permittivity and loss). F 2u(2) yielded the greatest contribution to dielectric constant and loss, which is mainly performed as the inverted translational vibration of Pr-MgO6 octahedron.

10.
Mol Biol Rep ; 38(6): 3751-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21104013

RESUMO

The techniques of homology cloning and anchored PCR were used to clone the fucose-binding lectin (F-type lectin) gene from Japanese sea perch (Lateolabrax Japonicus). The full-length cDNA of sea perch F-lectin (JspFL) contained a 5' untranslated region (UTR) of 39 bp, an ORF of 933 bp encoding a polypeptide of 310 amino acids with an estimated molecular mass of 10.82 kDa and a 3' UTR of 332 bp. The searches for nucleotides and protein sequence similarities with BLAST analysis indicated that the deduced amino acid sequence of JspFL was homological to the Fucose-binding lectin in other fish species. In the JspFL deduced amino acid sequence, two tandem domains that exhibit the eel carbohydrate-recognition sequence motif were found. The temporal expressions of gene in the different tissues were measured by real-time PCR. And the mRNA expressions of the gene were constitutively expressed in tissues including spleen, head-kidney, liver, gill, and heart. The JspFL expression in spleen was different during the stimulated time point, 2 h later the expression level became up-regulated, and 6 h later the expression level became down-regulated. The result indicated that JspFL was constitutive and inducible expressed and could play a critical role in the host-pathogen interaction.


Assuntos
Perfilação da Expressão Gênica , Lectinas/genética , Percas/genética , Animais , Clonagem Molecular , Regulação da Expressão Gênica/efeitos dos fármacos , Japão , Lectinas/metabolismo , Lipopolissacarídeos/farmacologia , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Baço/efeitos dos fármacos , Baço/metabolismo , Fatores de Tempo
11.
Mol Biol Rep ; 37(6): 2821-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19760093

RESUMO

The techniques of homology cloning and anchored PCR were used to clone the peroxiredoxin (Prx) gene from black tiger shrimp (Penaeus monodon). The full length cDNA of black tiger shrimp Prx (PmPrx) contained a 5' untranslated region (UTR) of 51 bp, an ORF (open reading frame) of 582 bp encoding a polypeptide of 193 amino acids with an estimated molecular mass of 22.15 kDa and a 3' UTR of 948 bp. Sequence comparison showed that PmPrx shared higher identities with Prx IVs than that with other isoforms of Prx, indicating PmPrx was a member of the Prx IV family. A quantitative reverse transcriptase Real-Time PCR (qRT-PCR) assay was developed to assess the mRNA expression of PmPrx in different tissues and the temporal expression of PmPrx in the hepatopancreas challenged by lipopolyssacharide (LPS). Higher-level mRNA expression of PmPrx was detected in the tissues of hepatopancreas, gonad and heart. The expression of PmPrx in the hepatopancreas was up regulated after stimulated by LPS. The results indicated that PmPrx was a constitutive and inducible expressed protein and could be induced by LPS.


Assuntos
Regulação da Expressão Gênica , Penaeidae/genética , Peroxirredoxinas/genética , Animais , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Dados de Sequência Molecular , Peroxirredoxinas/metabolismo , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Fatores de Tempo
12.
Gen Comp Endocrinol ; 163(3): 233-41, 2009 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-19361510

RESUMO

The growth hormone (GH) gene has been characterized for a number of fishes and used to establish phylogenetic relationships and as a candidate gene for studies of genetic variation in connection with growth traits. In this study, we report the genomic structure of Nibea coibor GH (designated as ncGH) including its 5'-flanking region, being cloned by homology-cloning and chromosome walking methods. The ncGH gene spans approximately 3.0 kb and consists of six exons and five introns, as found for all cloned teleost GH genes with the exception of carps and catfish. The 5'-flanking region contains consensus sequences for a TATA box, a CRE, a pit-1alpha, a TRE, two HNF-3, a ERE and a GRE. Five microsatellites are identified in the ncGH gene and three of them are polymorphic marker. The open reading frame (ORF) of ncGH is 615 bp in length encoding a polypeptide of 204 amino acids with an estimated molecular mass of 23.04 kDa and theoretical isoelectric point of 7.79. The precursor of ncGH consists of a 17 amino-acid signal peptide and a 187 amino-acid mature peptide. The four Cys residues are located at conserved positions (Cys(69), Cys(177), Cys(194) and Cys(202)), and One possible site for N-glycosylation (Asn-X-Ser/Thr motif) is present at Asn(201). The coding region sequence of ncGH is used to align with the sequences of 18 other species from Percoidei and one species from Anabantoidei using Clustal X. A matrix of 612 bp was used to construct the phylogenetic trees using neighbor-joining and maximum parsimony methods. The phylogenetic trees by two methods are identical in most of the clades with high bootstrap support. Every family all forms independent monophyly on the phylogenetic trees, in the family, the different species also forms the monophyly according to the different genera. The results are also identical to those from morphological data, and demonstrated that the GH gene is very suitable for phylogenetic relationship analysis of Percoidei. To validate the predicted exon/intron boundaries, ncGH cDNA is cloned using RT-PCR, and tissue distributions are investigated using semi-quantitative RT-PCR method. The results indicate that the predicted exon/intron is correct, the ncGH mRNA are mainly expressed in pituitary, and weakly expressed in ovary, brain, liver, gill, intestine, muscle and hear, but not expressed in spleen and kidney.


Assuntos
Hormônio do Crescimento/química , Hormônio do Crescimento/classificação , Repetições de Microssatélites/genética , Polimorfismo Genético/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Passeio de Cromossomo , Hormônio do Crescimento/genética , Dados de Sequência Molecular , Perciformes/classificação , Perciformes/genética , Perciformes/metabolismo , Filogenia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência
13.
Fish Shellfish Immunol ; 24(3): 323-36, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18201905

RESUMO

Interleukin-1 beta (IL-1 beta) is an important inflammatory mediator and has also the potential as an immunoadjuvant. Here we describe the isolation and characterization of yellowfin sea bream IL-1 beta (sbIL-1 beta) cDNA and gene. The sbIL-1 beta cDNA contains a 121-bp 5' untranslated region (UTR), a single open reading frame (ORF) of 762bp that translated into a 253 amino acid protein, a 342-bp 3' UTR with six cytokine RNA instability motifs (ATTTA), and a polyadenylation signal (AATAAA) at 13 nucleotides upstream of the poly (A) tail. The organization of the genomic IL-1 beta appears to be five exons and four introns, the intron and exon boundaries all follow the GT-AG consensus. The analysis of the expression pattern showed that sbIL-1 beta was expressed weakly in the kidney, spleen, gill and intestine, but not in the liver, heart and muscle. After injection with 150 microg LPS, the expression analysis in vivo showed that sbIL-1 beta was induced in the kidney and spleen and expression level was maximal after 4h. The predicted 253 amino acid sequence shares 23.5-88.5% identity and 43.9-93.3% similarity to known IL-1 beta. Thus, IL-1 beta is very conserved in fish of the same family. No interleukin-converting enzyme (ICE) cut site is found in sbIL-1 beta, but the alignment of the amino acid sequence with other species showed a possible cut site between Tyr87 and Thr88 that would give rise to a 166-amino-acid mature peptide. The putative mature peptide was expressed in E. coli, and the recombinant sbIL-1 beta could induce the transcription of sbIL-1 beta in a dose-dependent manner and the expression levels were almost equal in the samples treated with 50 ng/ml recombinant sbIL-1 beta and 5 microg/ml LPS, which showed recombinant sbIL-1 beta was biologically active and had the potential as an immunoadjuvant.


Assuntos
Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Dourada/genética , Dourada/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Escherichia coli/genética , Expressão Gênica , Genoma , Interleucina-1beta/química , Interleucina-1beta/isolamento & purificação , Leucócitos/metabolismo , Dados de Sequência Molecular , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico
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