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The in vivo effectiveness of DNAzymes 10-23 (Dz10-23) is limited due to the low concentration of divalent cations. Modifications of the catalytic loop are being sought to increase the activity of Dz10-23 in physiological conditions. We investigated the effect of 5'S or 5'R 5',8-cyclo-2'deoxyadenosine (cdA) on the activity of Dz10-23. The activity of Dz10-23 was measured in a cleavage assay using radiolabeled RNA. The Density Functional Tight Binding methodology with the self-consistent redistribution of Mulliken charge modification was used to explain different activities of DNAzymes. The substitution of 2'-deoxyadenosine with cdA in the catalytic loop decreased the activity of DNAzymes. Inhibition was dependent on the position of cdA and its absolute configuration. The order of activity of DNAzymes was as follows: wt-Dz > ScdA5-Dz ≈ RcdA15-Dz ≈ ScdA15-Dz > RcdA5-Dz. Theoretical studies revealed that the distance between phosphate groups at position 5 in RcdA5-Dz was significantly increased compared to wt-Dz, while the distance between O4 of dT4 and nonbonding oxygen of PO2 attached to 3'O of dG2 was much shorter. The strong inhibitory effect of RcdA5 may result from hampering the flexibility of the catalytic loop (increased rigidity), which is required for the proper positioning of Me2+ and optimal activity.
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DNA Catalítico , DNA Catalítico/metabolismo , Desoxiadenosinas , Modelos TeóricosRESUMO
Based on surface air temperature and precipitation, the current study examines the climate fluctuations over Sistan-and-Baluchestan Province, Iran's second-largest province. This area suffers from insufficient direct observations and a lack of climatic investigation. Three datasets were utilized including in situ data, gridded data (1984-2013), outputs of historical runs (during 1984-2013), and projections under the SSP5-8.5, SSP3-7.0, and SSP1-2.6 scenarios (in 2020-2049) of twenty-six Global Climate Models (GCMs) from the latest Coupled Model Intercomparison Project (CMIP6). The models' performance has been evaluated and ranked using the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) in Multi-Criteria Decision Making (MCDM) technique including eight metrics in both seasonal and annual scales. The surface air temperature showed an increasing trend in seasonal and annual scales during 1984-2013, while the monthly precipitation trend increased for September-October-November and decreased for the other seasons and annual scale during 1984-2013. The top-ranked models for simulating surface air temperature (precipitation) were CESM2 (GFDL-ESM4), IPSL-CM6A-LR (UKESM1-0-LL), ACCESS-CM2 (GFDL-ESM4), and MIROC-ES2L (MPI-ESM1-2-LR) models in DJF, MAM, JJA, and SON seasons, respectively, while ACCESS-CM2 (CNRM-CM6-1-HR) model outperformed others in annual scale. Bias-corrected outputs of the top-ranked CMIP6 GCMs showed an increasing trend for surface air temperature in all seasons (from a 0.7 K increase in December-January-February season under SSP3-7.0 scenario to a 2.5 K increase in June-July-August season under SSP5-8.5 scenario) for period 2020-2049, comparing with that in 1984-2013 period. Bias-corrected monthly precipitation projected by top-ranked CMIP6 GCMs indicated both increasing and decreasing trends depending on selected season and scenario. This varied from a 5 mm/month decrease within December-January-February season under SSP5-8.5 scenario to a 13 mm/month increase during the March-April-May season under SSP1-2.6 scenario in 2020-2050, comparing with that from previous years.
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Benchmarking , Monitoramento Ambiental , Irã (Geográfico) , Temperatura , Estações do AnoRESUMO
Composted manure and green waste amendments have been shown to increase net carbon (C) sequestration in rangeland soils and have been proposed as a means to help lower atmospheric CO2 concentrations. However, the effect of climate change on soil organic C (SOC) stocks and greenhouse gas emissions in rangelands is not well understood, and the viability of climate change mitigation strategies under future conditions is even less certain. We used a process-based biogeochemical model (DayCent) at a daily time step to explore the long-term effects of potential future climate changes on C and greenhouse gas dynamics in annual grassland ecosystems. We then used the model to explore how the same ecosystems might respond to climate change following compost amendments to soils and determined the long-term viability of net SOC sequestration under changing climates. We simulated net primary productivity (NPP), SOC, and greenhouse gas fluxes across seven California annual grasslands with and without compost amendments. We drove the DayCent simulations with field data and with site-specific daily climate data from two Earth system models (CanESM2 and HadGEM-ES) and two representative concentration pathways (RCP4.5 and RCP8.5) through 2100. NPP and SOC stocks in unamended and amended ecosystems were surprisingly insensitive to projected climate changes. A one-time amendment of compost to rangeland acted as a slow-release organic fertilizer and increased NPP by up to 390-814 kg C ha-1 year-1 across sites. The amendment effect on NPP was not sensitive to Earth system model or emissions scenario and endured through the end of the century. Net SOC sequestration amounted to 1.96 ± 0.02 Mg C ha-1 relative to unamended soils at the maximum amendment effect. Averaged across sites and scenarios, SOC sequestration peaked 22 ± 1 years after amendment and declined but remained positive throughout the century. Though compost stimulated nitrous oxide (N2 O) emissions, the cumulative net emissions (in CO2 equivalents) due to compost were far less than the amount of SOC sequestered. Compost amendments resulted in a net climate benefit of 69.6 ± 0.5 Tg CO2 e 20 ± 1 years after amendment if applied to similar ecosystems across the state, amounting to 39% of California's rangeland. These results suggest that the biogeochemical benefits of a single amendment of compost to rangelands in California are insensitive to climate change and could contribute to decadal-scale climate change mitigation goals alongside emissions reductions.
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Mudança Climática , Gases de Efeito Estufa , Ecossistema , Pradaria , Dióxido de Carbono , Solo , CarbonoRESUMO
Cyclohexan-1,3-dione derivatives are versatile scaffolds for the synthesis of a variety of value-added organic molecules including heterocycles and natural products. Six-membered oxygen heterocycles prepared from cyclohexan-1,3-diones are of much importance as they are intermediate for the synthesis of a number of natural products and several other valuable bioactive molecules which shows anti-viral, anti-bacterial, analgesic, antimalarial, anti-inflammatory, anti-allergic, anti-tumor and anti-cancer activities. These advantages have inspired us to write a detailed survey on the newly developed methods which are very essential in the construction of six-membered oxygen heterocycles. Further, the versatility in the chemistry of cyclohexan-1,3-dione and its derivatives is due to the presence of highly active methylene moiety and its active di-carbonyl groups. Recently, reactions of cyclohexane-1,3-dione and its derivatives with other substrates for instance aldehydes, malononitriles, NMSM, chalcones, isatin etc. have been established for the construction of a variety of six-membered oxygen heterocycles. The studies reported in this review article involved the synthesis of six-membered oxygen-containing heterocycles which includes 4H-chromen-5(6H)-one, 2H-xanthen-1(9H)-one, 2H-xanthen-1,8(5H,9H)-dione, 6H-chromen-2,5-dione derivatives and natural products having six-membered oxygen heterocycles from cyclohexane-1,3-dione and its derivatives as one of the substrate.
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Cicloexanos/química , Compostos Heterocíclicos/química , Oxigênio/química , Analgésicos/síntese química , Analgésicos/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/química , Benzopiranos/síntese química , Benzopiranos/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Compostos Heterocíclicos/síntese química , Sesquiterpenos/síntese química , Sesquiterpenos/química , Xantenos/síntese química , Xantenos/químicaRESUMO
Despite recent efforts to curtail greenhouse gas emissions, current global emission trajectories are still following the business-as-usual representative concentration pathway (RCP) 8.5 emission pathway. The resulting ocean warming and acidification have transformative impacts on coral reef ecosystems, detrimentally affecting coral physiology and health, and these impacts are predicted to worsen in the near future. In this study, we kept fragments of the symbiotic corals Acropora intermedia (thermally sensitive) and Porites lobata (thermally tolerant) for 7 weeks under an orthogonal design of predicted end-of-century RCP8.5 conditions for temperature and pCO2 (3.5°C and 570 ppm above present-day, respectively) to unravel how temperature and acidification, individually or interactively, influence metabolic and physiological performance. Our results pinpoint thermal stress as the dominant driver of deteriorating health in both species because of its propensity to destabilize coral-dinoflagellate symbiosis (bleaching). Acidification had no influence on metabolism but had a significant negative effect on skeleton growth, particularly when photosynthesis was absent such as in bleached corals or under dark conditions. Total loss of photosynthesis after bleaching caused an exhaustion of protein and lipid stores and collapse of calcification that ultimately led to A. intermedia mortality. Despite complete loss of symbionts from its tissue, P. lobata maintained small amounts of photosynthesis and experienced a weaker decline in lipid and protein reserves that presumably contributed to higher survival of this species. Our results indicate that ocean warming and acidification under business-as-usual CO2 emission scenarios will likely extirpate thermally sensitive coral species before the end of the century, while slowing the recovery of more thermally tolerant species from increasingly severe mass coral bleaching and mortality. This could ultimately lead to the gradual disappearance of tropical coral reefs globally, and a shift on surviving reefs to only the most resilient coral species.
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The association of genetic variants and congenital bilateral absence of the vas deferens (CBAVD) has been well acknowledged. By contrast, the link between nonobstructive azoospermia (NOA) or oligospermia and alterations in the cystic fibrosis transmembrane conductive regulator (CFTR) remains inconclusive. To clarify the problem, a meta-analysis was performed out after systematically searching Pubmed, Web of Science, Embase and the Chinese national knowledge infrastructure (CNKI) database. As we know, the ∆F508 and IVS8-5T gene mutations are the most studied genetic variants in CFTR gene. We reviewed the data from male patients who underwent the aforementioned genetic test. Our study revealed that the IVS8-5T mutation may be positively associated with the risk of nonobstructive male infertility (odds ratio (OR) 1.69; 95% CI: 1.12-2.55). This association strengthened when concerning NOA (OR: 2.62; 95% CI: 1.49-4.61). However, the ∆F508 mutation seemed to be a smaller contributing factor to this risk (OR: 1.63; 95% CI: 0.86-3.08). Our study aims to clarify the association between the ∆F508 and IVS8-5T gene mutations and nonobstructive male infertility. Therefore, screening for the IVS8-5T mutation in the CFTR gene may be recommended for men with NOA or severe oligozoospermia seeking assisted reproductive technology (ART).
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Regulador de Condutância Transmembrana em Fibrose Cística/genética , Infertilidade Masculina/genética , Humanos , Masculino , MutaçãoRESUMO
The phytotoxic potential of the leaves and twigs of Schumannianthus dichotomus, discarded in the mat-making industry against four test plants (lettuce (Lactuca sativa L.), rapeseed (Brassica napus L.), foxtail fescue (Vulpia myuros (L.) C.C. Gmel.) and timothy (Phleum pratense L.)) was investigated and found strong phytotoxic activity. An assay-guided fractionation of S. dichotomus extarcts against cress (Lepidium sativum L.) through a series of column chromatography steps yielded two compounds, 8-(5-oxo-2,5-dihydrofuran-2-yl) octanoic acid (ODFO) and (E)-6-hydroxy-2,6-dimethylocta-2,7-dienoic acid (8-carboxylinalool). ODFO and 8-carboxylinalool showed strong phytotoxic activity against cress and timothy. The concentrations required for 50% growth inhibition (I50 value) of the seedlings of cress and timothy were 111.94-128.01 and 36.30-91.75 µM, respectively, for ODFO, but the values were much higher at 315.98-379.13 and 107.92-148.41 µM, respectively, for 8-carboxylinalool, indicating the stronger phytotoxic activity of ODFO. This study is the first to isolate ODFO and 8-carboxylinalool from S. dichotomus and their phytotoxic potential while ODFO is firstly encountered from any natural source. The growth inhibitory activity of the identified compounds may explain their role in the phytotoxic activity of S. dichotomus, which suggests the possible use of its leaves and twigs or its active constituents as natural bioherbicides.
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Herbicidas/toxicidade , Marantaceae/química , Marantaceae/toxicidade , Resíduos , Brassica napus/efeitos dos fármacos , Brassica napus/crescimento & desenvolvimento , Brassicaceae/efeitos dos fármacos , Brassicaceae/crescimento & desenvolvimento , Lepidium sativum/efeitos dos fármacos , Lepidium sativum/crescimento & desenvolvimento , Lactuca/efeitos dos fármacos , Lactuca/crescimento & desenvolvimento , Estrutura Molecular , Extratos Vegetais/análise , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta/química , Caules de Planta/química , Poaceae/efeitos dos fármacos , Poaceae/crescimento & desenvolvimento , Plântula/efeitos dos fármacos , Testes de Toxicidade , Resíduos/análiseRESUMO
Human lymphocyte antigen (HLA) class I molecules play a central role in cytotoxic T lymphocytes (CTL)-based antitumor immunity. However, the expression rate of HLA class I in cancer cells remains a topic of discussion. We compared HLA class I expression levels between cancer cells and surrounding non-tumorous hepatocytes in 20 early-stage hepatocellular carcinoma (HCC) patients by immunohistochemistry using EMR 8-5. The expression levels of HLA class I were classified as negative, incomplete positive or complete positive. Similarly, for various types of solid cancers, HLA class I expression was examined. For the HLA class I expression in cancer cells, among 20 HCC patients, 13 were complete positive, 3 were incomplete positive, and 4 were negative. In addition, 15 (75.0%) had higher expression levels of HLA class I in cancer cells compared with that in surrounding non-tumorous hepatocytes. An interferon-γ (IFN-γ) enzyme-linked immunospot (ELISPOT) assay indicated that cancer cells with positive expression of HLA class I had strong sensitivity to antigen-specific CTL. We suggested that HLA class I expression in cancer cells could be involved in the clinical prognosis of HCC patients. Similarly, 66.7%, 100.0%, 66.7% and 62.5% of patients with early-stage pancreatic, gallbladder, esophageal and breast cancers, respectively, had higher expression levels of HLA class I in cancer cells than in surrounding normal tissue cells. We suggest that in several early-stage solid cancers, including HCC, HLA class I expression levels in cancer cells are higher than that in surrounding normal tissue cells, which could result in the anti-tumor effect of CTL-based cancer immunotherapy.
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Carcinoma Hepatocelular/imunologia , Antígenos HLA/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Neoplasias Hepáticas/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Feminino , Antígenos HLA/biossíntese , Antígenos de Histocompatibilidade Classe I/biossíntese , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismoRESUMO
The timing of the annual phytoplankton spring bloom is likely to be altered in response to climate change. Quantifying that response has, however, been limited by the typically coarse temporal resolution (monthly) of global climate models. Here, we use higher resolution model output (maximum 5 days) to investigate how phytoplankton bloom timing changes in response to projected 21st century climate change, and how the temporal resolution of data influences the detection of long-term trends. We find that bloom timing generally shifts later at mid-latitudes and earlier at high and low latitudes by ~5 days per decade to 2100. The spatial patterns of bloom timing are similar in both low (monthly) and high (5 day) resolution data, although initiation dates are later at low resolution. The magnitude of the trends in bloom timing from 2006 to 2100 is very similar at high and low resolution, with the result that the number of years of data needed to detect a trend in phytoplankton phenology is relatively insensitive to data temporal resolution. We also investigate the influence of spatial scales on bloom timing and find that trends are generally more rapidly detectable after spatial averaging of data. Our results suggest that, if pinpointing the start date of the spring bloom is the priority, the highest possible temporal resolution data should be used. However, if the priority is detecting long-term trends in bloom timing, data at a temporal resolution of 20 days are likely to be sufficient. Furthermore, our results suggest that data sources which allow for spatial averaging will promote more rapid trend detection.
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Mudança Climática , Fitoplâncton/fisiologia , Dinâmica Populacional , Estações do Ano , Temperatura , Fatores de TempoRESUMO
Polar cod (Boreogadus saida) is an important prey species in the Arctic ecosystem, yet its habitat is changing rapidly: climate change, through rising seawater temperatures and CO2 concentrations, is projected to be most pronounced in Arctic waters. This study aimed to investigate the influence of ocean acidification and warming on maximum performance parameters of B. saida as indicators for the species' acclimation capacities under environmental conditions projected for the end of this century. After 4 months at four acclimation temperatures (0, 3, 6, 8°C) each combined with two PCO2 levels (390 and 1170â µatm), aerobic capacities and swimming performance of B. saida were recorded following a Ucrit protocol. At both CO2 levels, standard metabolic rate (SMR) was elevated at the highest acclimation temperature indicating thermal limitations. Maximum metabolic rate (MMR) increased continuously with temperature, suggesting an optimum temperature for aerobic scope for exercise (ASex) at 6°C. Aerobic swimming performance (Ugait) increased with acclimation temperature irrespective of CO2 levels, while critical swimming speed (Ucrit) did not reveal any clear trend with temperature. Hypercapnia evoked an increase in MMR (and thereby ASex). However, swimming performance (both Ugait and Ucrit) was impaired under elevated near-future PCO2 conditions, indicating reduced efficiencies of oxygen turnover. The contribution of anaerobic metabolism to swimming performance was very low overall, and further reduced under hypercapnia. Our results revealed high sensitivities of maximum performance parameters (MMR, Ugait, Ucrit) of B. saida to ocean acidification. Impaired swimming capacity under ocean acidification may reflect reduced future competitive strength of B. saida.
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Gadiformes/fisiologia , Aquecimento Global , Água do Mar/química , Natação/fisiologia , Aclimatação/fisiologia , Animais , Regiões Árticas , Metabolismo Basal/fisiologia , Dióxido de Carbono/metabolismo , Dióxido de Carbono/farmacologia , Gadiformes/metabolismo , Concentração de Íons de Hidrogênio , Hipercapnia/fisiopatologia , TemperaturaRESUMO
The distribution of lignin, 8-5' and 8-8' linked lignin substructure, and noncellulosic polysaccharides in hemp (Cannabis sativa L.) phloem fibers were explored based on histochemical and immunological methods. Ultraviolet absorption and potassium permanganate staining were observed mainly in the compound middle lamella (CML) and S1 layers, and rarely in the G-layer of phloem fibers, suggesting that lignin concentration is high at the CML and S1 layers, and very low at the G-layer of hemp fibers. Acriflavine staining, uniform KM1 labeling (8-5' linked lignin substructure), and no KM2 labeling (8-8' linked structure) were observed in the G-layer, suggesting that there is a small amount of lignin-like compound with 8-5' linked structure in the G-layer. In addition, some fiber cells showed a multilayered structure. Uniform arabinogalactan protein (AGP) labeling was observed on the S1 layers and G-layers using JIM14, but little appeared in the CML of hemp fibers, indicating that these layers of the phloem fibers contain AGP. Immunogold labeling of xylan (LM11) and glucomannan (LM21) showed that xylan and glucomannan were mainly present in the S1 layers and the G-layers, respectively. In some phloem fibers, LM21 immunofluorescence labeling showed multilayered structure, suggesting the heterogeneous distribution of glucomannan.
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Cannabis/química , Parede Celular/química , Galactanos/metabolismo , Lignina/metabolismo , Floema/química , Polissacarídeos/metabolismo , Anticorpos Monoclonais/imunologia , Imunofluorescência , Lignina/imunologia , Mananas/análise , Coloração e Rotulagem , Xilanos/análiseRESUMO
BACKGROUND: Ocean acidification and warming are happening fast in the Arctic but little is known about the effects of ocean acidification and warming on the physiological performance and survival of Arctic fish. RESULTS: In this study we investigated the metabolic background of performance through analyses of cardiac mitochondrial function in response to control and elevated water temperatures and PCO2 of two gadoid fish species, Polar cod (Boreogadus saida), an endemic Arctic species, and Atlantic cod (Gadus morhua), which is a temperate to cold eurytherm and currently expanding into Arctic waters in the wake of ocean warming. We studied their responses to the above-mentioned drivers and their acclimation potential through analysing the cardiac mitochondrial function in permeabilised cardiac muscle fibres after 4 months of incubation at different temperatures (Polar cod: 0, 3, 6, 8 °C and Atlantic cod: 3, 8, 12, 16 °C), combined with exposure to present (400µatm) and year 2100 (1170µatm) levels of CO2. OXPHOS, proton leak and ATP production efficiency in Polar cod were similar in the groups acclimated at 400µatm and 1170µatm of CO2, while incubation at 8 °C evoked increased proton leak resulting in decreased ATP production efficiency and decreased Complex IV capacity. In contrast, OXPHOS of Atlantic cod increased with temperature without compromising the ATP production efficiency, whereas the combination of high temperature and high PCO2 depressed OXPHOS and ATP production efficiency. CONCLUSIONS: Polar cod mitochondrial efficiency decreased at 8 °C while Atlantic cod mitochondria were more resilient to elevated temperature; however, this resilience was constrained by high PCO2. In line with its lower habitat temperature and higher degree of stenothermy, Polar cod has a lower acclimation potential to warming than Atlantic cod.
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The synthesis, SAR, and preclinical characterization of a series of substituted 6,7-dihydro[1,2,4]triazolo[4,3]pyrazin-8(5H)-one P2X7 receptor antagonists are described. Optimized leads from this series comprise some of the most potent human P2X7R antagonists reported to date (IC50s<1nM). They also exhibit sufficient potency and oral bioavailability in rat to enable extensive in vivo profiling. Although many of the disclosed compounds are peripherally restricted, compound 11d is brain penetrant and upon oral administration demonstrated dose-dependent target engagement in rat hippocampus as determined by ex vivo receptor occupancy with radiotracer 5 (ED50=0.8mg/kg).
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Fármacos do Sistema Nervoso Central/farmacologia , Antagonistas do Receptor Purinérgico P2X/farmacologia , Pirazinas/farmacologia , Triazóis/farmacologia , Animais , Barreira Hematoencefálica/metabolismo , Células CACO-2 , Fármacos do Sistema Nervoso Central/síntese química , Fármacos do Sistema Nervoso Central/farmacocinética , Hipocampo/metabolismo , Humanos , Microssomos Hepáticos/metabolismo , Antagonistas do Receptor Purinérgico P2X/síntese química , Antagonistas do Receptor Purinérgico P2X/farmacocinética , Pirazinas/síntese química , Pirazinas/farmacocinética , Ratos , Receptores Purinérgicos P2X7/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/farmacocinética , TrítioRESUMO
Climate change could shift the phenology of insects and plants and alter their linkage in space and time. We examined the synchrony of rice and its insect pest, Scotinophara lurida (Burmeister), under the representative concentration pathways (RCP) 8.5 climate change scenario by comparing the mean spring immigration time of overwintered S. lurida with the mean rice transplanting times in Korea. The immigration time of S. lurida was estimated using an overwintered adult flight model. The rice transplanting time of three cultivars (early, medium, and medium-late maturing) was estimated by forecasting the optimal cultivation period using leaf appearance and final leaf number models. A temperature increase significantly advanced the 99% immigration time of S. lurida from Julian day 192.1 in the 2000s to 178.4 in the 2050s and 163.1 in the 2090s. In contrast, rice transplanting time was significantly delayed in the early-maturing cultivar from day 141.2 in the 2000s to 166.7 in the 2050s and 190.6 in the 2090s, in the medium-maturing cultivar from day 130.6 in the 2000s to 156.6 in the 2050s and 184.7 in the 2090s, and in the medium-late maturing cultivar from day 128.5 in 2000s to 152.9 in the 2050s and 182.3 in the 2090s. These simulation results predict a significant future phenological asynchrony between S. lurida and rice in Korea.
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Mudança Climática , Hemípteros/fisiologia , Modelos Teóricos , Oryza/crescimento & desenvolvimento , Estações do Ano , Animais , Folhas de Planta/crescimento & desenvolvimento , República da Coreia , TemperaturaRESUMO
This dataset provides annual statistical descriptors (mean, minimum, maximum, range and standard deviation) of key biogeochemical and physical variables for the Mediterranean Sea. It covers the period 2005-2099 under a high emissions scenario (CMIP5-RCP8.5), with a spatial resolution of 1/24 degree (â¼4 km²). The CMIP5-RCP8.5 scenario considers the current trajectory of increasing greenhouse gas emissions and population growth to the end of the century with nominal policies to reduce emissions. Variables include temperature, salinity, pH, water velocity, nutrients (NO3, PO4, NH4), dissolved inorganic carbon, oxygen, and net primary production. Data are available for both surface and at bathymetry level. The original projections were generated using OGSTM-BFM and MFS16 models at daily time and 1/16 degree grid resolution. These were downscaled to 1/24 degree resolution and bias corrected by quantile delta mapping using CMEMS reanalysis products from 2005 to 2020. The dataset is provided in a user-friendly format so that it is accessible for various ecological and environmental modelling applications.
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Artocarpus altilis, commonly known as breadfruit, is a potential crop adapted to a wide variety of climates and widely spread, including in Indonesia. However, information on how this species can adapt to climate change, in particular in Central Java, is still limited. In Indonesia, Central Java is the center for cultivation areas for many crop species to support the 145 million people living on Java Island. One of the potential crops being developed in Central Java is breadfruit. To assess the suitable cultivation areas for breadfruit, species distribution modeling (SDM) was used to predict the current and future (2050-2070) distribution of breadfruit. Two climate change scenarios, including optimistic RCP2.6 and pessimistic RCP8.5 models, were considered to represent future climate change impacts. Based on the results for both optimistic and pessimistic scenarios, the breadfruit's suitable cultivation areas will expand eastward. Implementing a mitigation climate change scenario and limiting the temperature increase to only 1°C under RCP2.6 will provide 270.967 km2 more of suitable cultivation areas for breadfruit in 2050 and 133.296 km2 in 2070. To conclude, this study provides important information on the status and potential cultivation areas for breadfruit, mainly in the Southeast Asia region. The identification of suitable areas will guide land conservation for breadfruit to support food security in this region.
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Vegetation redistribution may bring unexpected climate-soil carbon cycling in terrestrial biomes. However, whether and how vegetation redistribution alters the soil carbon pool under climate change is still poorly understood on the Tibetan Plateau. Here, we applied the G-Range model to simulate the cover of herbs, shrubs and trees, net primary productivity (NPP) and soil organic carbon density (SOCD) at the depth of 60 cm on Tibetan Plateau for the individual years 2020 and 2060, using climate projection for Representative Concentration Pathways (RCP) 4.5 and RCP8.5 scenarios with the RegCM4.6 model system. Vegetation redistribution was defined as the transitions in bare ground, herbs, shrubs and trees between 2020 and 2060, with approximately 57.9 % (RCP4.5) and 59 % (RCP8.5) of the area will redistribute vegetation over the whole Tibetan Plateau. The vegetation cover will increase by about 2.4 % (RCP4.5) and 1.9 % (RCP8.5), while the NPP and SOCD will decrease by about -14.3 g C m-2 yr-1 and -907 g C m-2 (RCP4.5), and -1.8 g C m-2 yr-1and -920 g C m-2 (RCP8.5). Shrubs and trees will expand in the east, and herbs will expand in the northwest part of the Plateau. These areas are projected to be hotspots with greater SOCD reduction in response to future climate change, and will include lower net plant carbon input due to the negative NPP. Our study indicates that the SOC pool will become a carbon source under increased air temperature and rainfall on the Tibetan Plateau by 2060, especially for the area with vegetation redistribution. These results revealed the potential risk of vegetation redistribution under climate change in alpine ecosystems, indicating the policymakers need to pay attention on the vegetation redistribution to mitigate the soil carbon emission and achieve the goal of carbon neutrality on the Tibetan Plateau.
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Climate change is having important effects on the migration routes and seasonal-spatial distribution patterns of aquatic animals, including the cephalopods Sepiella maindroni de Rochebrune (Hoyle, 1886) and Sepia kobiensis (Hoyle, 1885) in the East China Sea region. We conducted bottom trawling surveys from 2018 to 2019 in the East China Sea region to identify the seasonal-spatial distribution patterns, including the locations of spawning and nursery grounds of both species, and to determine how they are related to environmental variables. We used random forests and boosted regression trees to identify the distribution patterns of both species from spring to winter to estimate the annual mean situations. We also predicted the habitat distribution variations in 2050 and 2100 under the SSP1-2.6 and SSP5-8.5 climate change scenarios. From our survey data, we detected increasing biomass densities of S. maindroni from 29.50° N to 28.50° N, where the largest value of 213.92 g·ind-1 occurred. In spring, juvenile groups were present in coastal areas and larger individuals were found in offshore areas. We identified potential spawning grounds at 29.50°-33.00° N 122.50°-123.00° E adjacent to the Zhejiang coastline, and larger individuals and higher biomass densities in south of the 29.50° N line in summer. In autumn, the average individual weight increased in the 28.00° N 122.00° Eâ124.00° E area. We located potential S. kobiensis spawning grounds at 27.00° N 122.00°-123.50° E in spring. Growing overwintering juveniles migrated to the area of 29.50°-30.50° N 125.00°-127.00° E in winter. The sea surface temperature of the areas inhabited by both species showed obvious seasonal variation. The SSP1-2.6 and SSP5-8.5 scenarios indicated that the habitat of S. maindroni would shift to the south first and then to the north of the study area with the intensification of CO2 emissions, and it would first expand and then greatly decrease. However, the habitat area of S. kobiensis would increase. Our results will contribute to a better understanding of the life history traits of both species and the changes in their distribution patterns under different climate scenarios to ensure sustainable exploitation and fisheries management.
RESUMO
Global climate change profoundly impacts the East China Sea ecosystem and poses a major challenge to fishery management in this region. In addition, closely related species with low catches are often not distinguished in fishery production and relevant data are commonly merged in statistics and fishing logbooks, making it challenging to accurately predict their habitat distribution range. Here, merged fisheries-independent data of the closely related squid Loliolus beka (Sasaki, 1929) and Loliolus uyii (Wakiya and Ishikawa, 1921) were used to explore the construction and prediction performance of species distribution models. Data in 2018 to 2019 from the southern Yellow and East China Seas were used to identify the seasonal-spatial distribution characteristics of both species, revealing a boundary line at 29.00° N for L. uyii during the autumn, with the highest average individual weight occurring during the summer, with both larvae and juveniles occurring during the autumn. Thus, the life history of L. uyii can be divided into winter-spring nursery and summer-autumn spawning periods. L. beka showed a preference for inshore areas (15-60 m) during the summer and offshore areas (32.00-78.00 m) during the winter. High-value areas of both species included inshore areas of the southern Yellow and mid-East China Seas during the autumn, enlarging during the spring to include central areas of the survey region, before significantly decreasing during the summer. Therefore, this study provides both a novel perspective for modeling biological habitat distribution with limited data and a scientific basis for the adjustment of fishery resource management and conservation measures in the context of climate change.
RESUMO
Traditionally produced fish sauce can contain significant amounts of histamine. In some instances, the histamine concentration may be well above the limit recommended by the Codex Alimentarius Commission. The aim of this study was to discover new bacterial strains capable of growing under the stressful environmental conditions of fish sauce fermentation and metabolizing histamine. In this study, 28 bacterial strains were isolated from Vietnamese fish sauce products based on their ability to grow at high salt concentrations (23% NaCl) and tested for their ability to degrade histamine. Strain TT8.5 showed the highest histamine-degradation (45.1 ± 0.2% of initially 5 mM histamine within 7 days) and was identified as Virgibacillus campisalis TT8.5. Its histamine-degrading activity was shown to be localized intracellularly and the enzyme is a putative histamine dehydrogenase. The strain exhibited optimal growth and histamine-degrading activity at 37°C, pH 7%, and 5% NaCl in halophilic archaea (HA) histamine broth. It also showed pronounced histamine-degrading activity in HA histamine broth when cultivated at temperatures of up to 40 °C as well as in the presence of up to 23% NaCl. After treatment with immobilized cells, 17.6-26.9% of the initial histamine in various fish sauce products were reduced within 24 h of incubation, while no significant changes in other parameters of fish sauce quality were observed after this treatment. Our results indicate that V. campisalis TT8.5 is of potential interest to be applied in histamine degradation of traditional fish sauce.