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1.
Int J Biol Macromol ; 264(Pt 2): 130820, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38484812

RESUMEN

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its variants has resulted in global economic losses and posed a threat to human health. The pandemic highlights the urgent need for an efficient, easily producible, and broad-spectrum vaccine. Here, we present a potentially universal strategy for the rapid and general design of vaccines, focusing on the design and testing of omicron BA.5 RBD-conjugated self-assembling ferritin nanoparticles (NPs). The covalent bonding of RBD-Fc to protein A-ferritin was easily accomplished through incubation, resulting in fully multivalent RBD-conjugated NPs that exhibited high structural uniformity, stability, and efficient assembly. The ferritin nanoparticle vaccine synergistically stimulated the innate immune response, Tfh-GCB-plasma cell-mediated activation of humoral immunity and IFN-γ-driven cellular immunity. This nanoparticle vaccine induced a high level of cross-neutralizing responses and protected golden hamsters challenged with multiple mutant strains from infection-induced clinical disease, providing a promising strategy for broad-spectrum vaccine development for SARS-CoV-2 prophylaxis. In conclusion, the nanoparticle conjugation platform holds promise for its potential universality and competitive immunization efficacy and is expected to facilitate the rapid manufacturing and broad application of next-generation vaccines.


Asunto(s)
COVID-19 , Nanopartículas , Animales , Cricetinae , Humanos , SARS-CoV-2 , COVID-19/prevención & control , Vacunas contra la COVID-19 , Inmunidad Innata , Ferritinas/genética , Nanovacunas , Anticuerpos Neutralizantes , Anticuerpos Antivirales
2.
Antiviral Res ; 225: 105854, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38447647

RESUMEN

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with frequent mutations has seriously damaged the effectiveness of the 2019 coronavirus disease (COVID-19) vaccine. There is an urgent need to develop a broad-spectrum vaccine while elucidating the underlying immune mechanisms. Here, we developed a SARS-CoV-2 virus-like particles (VLPs) vaccine based on the Canarypox-virus vector (ALVAC-VLPs) using CRISPR/Cas9. Immunization with ALVAC-VLPs showed the effectively induce SARS-CoV-2 specific T and B cell responses to resist the lethal challenge of mouse adaptive strains. Notably, ALVAC-VLPs conferred protection in golden hamsters against SARS-CoV-2 Wuhan-Hu-1 (wild-type, WT) and variants (Beta, Delta, Omicron BA.1, and BA.2), as evidenced by the prevention of weight loss, reduction in lung and turbinate tissue damage, and decreased viral load. Further investigation into the mechanism of immune response induced by ALVAC-VLPs revealed that toll-like receptor 4 (TLR4) mediates the recruitment of dendritic cells (DCs) to secondary lymphoid organs, thereby initiating follicle assisted T (Tfh) cell differentiation, the proliferation of germinal center (GC) B cells and plasma cell production. These findings demonstrate the immunogenicity and efficacy of the safe ALVAC-VLPs vaccine against SARS-CoV-2 and provide valuable insight into the development of COVID-19 vaccine strategies.


Asunto(s)
COVID-19 , Vacunas de Partículas Similares a Virus , Ratones , Animales , Humanos , SARS-CoV-2 , Vacunas contra la COVID-19 , Sistemas CRISPR-Cas , Edición Génica , Anticuerpos Antivirales , Anticuerpos Neutralizantes
3.
Environ Monit Assess ; 195(10): 1148, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37668812

RESUMEN

Vegetation makes an outstanding contribution to the stability of ecosystems and to a certain extent reflects the state of the terrestrial ecosystem. Drought conditions greatly affect the growth and development process of vegetation due to its remarkable stochasticity and complexity. Due to the complex coupling mechanism between vegetation and drought, the research on vegetation drought risk is still limited. In this work, we focus on Northwest China and use the improved vegetation health index (VHI) and other multi-source data. We selected indicator factors based on both hazard and vulnerability, and adopt three weight determination methods, namely entropy method, critic method, and coefficient of variation method, to construct the corresponding index model, and also to establish a vegetation drought risk assessment model to quantitatively evaluate the drought risk of vegetation in northwest China. Results show that the percentage of each drought category remarkably changed during the period encompassing 1981-2020, and the vegetation drought shows deterioration in more areas of northwest China. The vegetation drought risks derived from the three weight determination methods were generally consistent, but differed for a particular vegetation type. The overall spatial distribution pattern of vegetation drought risk in Northwest China is higher in the west and lower in the east, and the vegetation in southern Qinghai and northwestern Xinjiang presents higher drought risk. This study may be used as a tool to provide quantitative basis for vegetation protection and vegetation drought management.


Asunto(s)
Sequías , Ecosistema , Monitoreo del Ambiente , China , Medición de Riesgo
4.
BMC Genomics ; 24(1): 224, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37127571

RESUMEN

BACKGROUND: The receptor-like kinase (RLK) gene families in plants contains a large number of members. They are membrane proteins with an extracellular receptor domain and participate in biotic and abiotic stress responses. RESULTS: In this study, we identified RLKs in 15 representative plant genomes, including wheat, and classified them into 64 subfamilies by using four types of phylogenetic trees and HMM models. Conserved exon‒intron structures with conserved exon phases in the kinase domain were found in many RLK subfamilies from Physcomitrella patens to Triticum aestivum. Domain distributions of RLKs were also diagrammed. Collinearity events and tandem gene clusters suggested that polyploidization and tandem duplication events contributed to the member expansions of T. aestivum RLKs. Global expression pattern analysis was performed by using public transcriptome data. These analyses were involved in T. aestivum, Aegilops tauschii and Brachypodium distachyon RLKs under biotic and abiotic stresses. We also selected 9 RLKs to validate the transcriptome prediction by using qRT‒PCR under drought treatment and with Fusarium graminearum infection. The expression trends of these 9 wheat RLKs from public transcriptome data were consistent with the results of qRT‒PCR, indicating that they might be stress response genes under drought or F. graminearum treatments. CONCLUSION: In this study, we identified, classified, evolved, and expressed RLKs in wheat and related plants. Thus, our results will provide insights into the evolutionary history and molecular mechanisms of wheat RLKs.


Asunto(s)
Proteínas de Plantas , Triticum , Filogenia , Triticum/genética , Proteínas de Plantas/genética , Genes de Plantas , Plantas/genética , Genoma de Planta , Familia de Multigenes , Proteínas Tirosina Quinasas/genética , Estrés Fisiológico/genética , Regulación de la Expresión Génica de las Plantas
5.
Sci Rep ; 11(1): 16954, 2021 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-34417492

RESUMEN

Hydrological models are widely used as simplified, conceptual, mathematical representatives for water resource management. The performance of hydrological modeling is usually challenged by model calibration and uncertainty analysis during modeling exercises. In this study, a multicriteria sequential calibration and uncertainty analysis (MS-CUA) method was proposed to improve the efficiency and performance of hydrological modeling with high reliability. To evaluate the performance and feasibility of the proposed method, two case studies were conducted in comparison with two other methods, sequential uncertainty fitting algorithm (SUFI-2) and generalized likelihood uncertainty estimation (GLUE). The results indicated that the MS-CUA method could quickly locate the highest posterior density regions to improve computational efficiency. The developed method also provided better-calibrated results (e.g., the higher NSE value of 0.91, 0.97, and 0.74) and more balanced uncertainty analysis results (e.g., the largest P/R ratio values of 1.23, 2.15, and 1.00) comparing with other traditional methods for both case studies.

6.
Carbon Balance Manag ; 16(1): 24, 2021 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-34398330

RESUMEN

BACKGROUND: Soil organic carbon (SOC) plays a crucial role in the global carbon cycle and terrestrial ecosystem functions. It is widely known that climate change and soil water content (SWC) could influence the SOC dynamics; however, there are still debates about how climate change, especially climate warming, and SWC impact SOC. We investigated the spatiotemporal changes in SOC and its responses to climate warming and root-zone SWC change using the coupled hydro-biogeochemical model (SWAT-DayCent) and climate scenarios data derived under the three Representative Concentration Pathways (RCPs2.6, 4.5, and 8.5) from five downscaled Global Climate Models (GCMs) in a typical loess watershed--the Jinghe River Basin (JRB) on the Chinese Loess Plateau. RESULTS: The air temperature would increase significantly during the future period (2017-2099), while the annual precipitation would increase by 2.0-13.1% relative to the baseline period (1976-2016), indicating a warmer and wetter future in the JRB. Driven by the precipitation variation, the root-zone SWC would also increase (by up to 27.9% relative to the baseline under RCP4.5); however, the SOC was projected to decrease significantly under the future warming climate. The combined effects of climate warming and SWC change could more reasonably explain the SOC loss, and this formed hump-shaped response surfaces between SOC loss and warming-SWC interactions under both RCP2.6 and 8.5, which can help explain diverse warming effects on SOC with changing SWC. CONCLUSIONS: The study showed a significant potential carbon source under the future warmer and wetter climate in the JRB, and the SOC loss was largely controlled by future climate warming and the root-zone SWC as well. The hump-shaped responses of the SOC loss to climate warming and SWC change demonstrated that the SWC could mediate the warming effects on SOC loss, but this mediation largely depended on the SWC changing magnitude (drier or wetter soil conditions). This mediation mechanism about the effect of SWC on SOC would be valuable for enhancing soil carbon sequestration in a warming climate on the Loess Plateau.

7.
Viruses ; 13(7)2021 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-34209472

RESUMEN

West Nile virus disease (WND) is an arthropod-borne zoonosis responsible for nonspecific fever or severe encephalitis. The pathogen is West Nile virus belonging to the genus Flavivirus, family Flaviviridae. Every year, thousands of cases were reported, which poses significant public health risk. Here, we constructed a West Nile virus chimera, ChiVax-WN01, by replacing the prMΔE gene of JEV SA14-14-2 with that of the West Nile virus NY99. The ChiVax-WN01 chimera showed clear, different characters compared with that of JEV SA14-14-2 and WNV NY99 strain. An animal study indicated that the ChiVax-WN01 chimera presented moderate safety and immunogenicity for 4-week female BALB/c mice.


Asunto(s)
Quimera , Virus de la Encefalitis Japonesa (Especie)/genética , Virus del Nilo Occidental/genética , Animales , Línea Celular , Cricetinae , Virus de la Encefalitis Japonesa (Especie)/patogenicidad , Femenino , Ratones , Ratones Endogámicos BALB C , Virulencia , Virus del Nilo Occidental/patogenicidad
8.
BMC Vet Res ; 17(1): 172, 2021 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-33892731

RESUMEN

BACKGROUND: Canine distemper virus (CDV) is an enveloped negative-strand RNA virus that exhibits a high mutation rate and continuously expands the range of hosts. Notably, CDV has infected giant panda with spill over from viral reservoirs in canines. Giant pandas (Ailuropoda melanoleuca), especially captive pandas, are known to be susceptible to natural infection with CDV. The high fatality rate of CDV poses a serious threat to the safety of the giant panda population. However, vaccines or drugs for canine distemper in giant pandas have not been developed to date. Therefore, a rapid test that can achieve accurate onsite detection of CDV is important to enable the timely implementation of control measures. In this study, we established a nucleic acid visualization assay for targeting the CDV N gene by using combines reverse transcription recombinase polymerase amplification with a closed vertical flow visualization strip (RT-RPA-VF). RESULTS: The RT-RPA-VF assay does not require sophisticated equipment, and it was determined to provide rapid detection at 35 °C for 30 min, while the limit of detection was 5 × 101 copies/µl RNA transcripts and 100.5 TCID50 ml- 1 viruses. The results showed that the assay was high specific to CDV and had no cross-reactivity with other viruses infecting the giant panda. Compared with RT-qPCR, RT-RPA-VF assay had a sensitivity of 100% and a specificity of 100% in 29 clinical samples. The coincidence rate between RT-RPA-VF and RT-qPCR was 100% (kappa = 1), indicating that the RT-RPA-VF assay possessed good diagnostic performance on clinical samples. CONCLUSIONS: The RT-RPA-VF provides a novel alternative for the simple, sensitive, and specific identification of CDV and showed great potential for point of care diagnostics for captive and wild giant panda.


Asunto(s)
Virus del Moquillo Canino/genética , Virus del Moquillo Canino/aislamiento & purificación , Moquillo/diagnóstico , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Ursidae/virología , Animales , Moquillo/virología , Técnicas de Amplificación de Ácido Nucleico/métodos , ARN Viral , Reacción en Cadena en Tiempo Real de la Polimerasa/veterinaria , Transcripción Reversa , Sensibilidad y Especificidad
9.
Front Cell Infect Microbiol ; 11: 820144, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35198456

RESUMEN

A feline panleukopenia virus (FPV), Giant panda/CD/2018, was isolated from a captive giant panda with mild diarrhea in 2018 in Chengdu, China, and further identified via indirect immunofluorescence assay (IFA), transmission electron microscopy (TEM) observation, and genetic analysis. Phylogenetic analysis based on the complete VP2 nucleotide sequences showed that it shared high homology with Chinese FPV isolates and grouped within FPV cluster 1. One unique substitution Gly(G)299Glu(E) in the capsid protein VP2 was first identified with Giant panda/CD/2018. The presence of the G299E substitution is notable as it is located on the top region of the interconnecting surface loop 3, which may be involved in controlling the host range and antigenicity of FPV. These findings first demonstrate that FPV with natural point mutation G299E in the VP2 gene is prevalent in giant panda and suggest that etiological surveillance and vaccination among all giant pandas are urgently needed to protect this endangered species against FPV infection.


Asunto(s)
Virus de la Panleucopenia Felina , Infecciones por Parvoviridae , Ursidae , Animales , Animales de Zoológico/virología , Proteínas de la Cápside/genética , China/epidemiología , Diarrea/veterinaria , Diarrea/virología , Virus de la Panleucopenia Felina/genética , Infecciones por Parvoviridae/veterinaria , Filogenia , Ursidae/virología
10.
Vet Microbiol ; 251: 108920, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33197867

RESUMEN

Canine distemper virus (CDV) is the causative agent of canine distemper (CD), which is one of the most important infectious diseases affecting wild and domestic carnivores. Vaccination represents an effective approach to prevent CDV infection among domestic carnivores. Canarypox-vectored recombinant CD vaccines (such as Recombitek CDV, PureVax Ferret Distemper, and Merial) with the CDV hemagglutinin (H) and fusion (F) genes can induce a potent immune response in dogs and ferrets. However, the vaccine's effectiveness varies with the species. In the current study, we developed a highly efficient recombinant canarypox virus termed as "ALVAC-CDV-M-F-H/C5-" that contained CDV virus-like particles (VLPs) by using the CRISPR/Cas9 gene editing method, which enabled concurrent expression of the matrix (M), H, and F genes. The recombinant strain provided faster seroconversion than the parent strain among minks as well as provided higher rates of antibody positivity than the parent strain among foxes and minks even before the administration of a second booster vaccination. We demonstrated, for the first time, that the CRISPR/Cas9 system can be applied for the rapid and efficient modification of the ALVAC-CDV-F-H genome and also that a high-dose new recombinant strain that produces CDV VLPs may present good outcomes in the prevention of CD among foxes and minks.


Asunto(s)
Anticuerpos Antivirales/sangre , Sistemas CRISPR-Cas , Virus de la Viruela de los Canarios/genética , Virus del Moquillo Canino/genética , Virus del Moquillo Canino/inmunología , Moquillo/prevención & control , Edición Génica/métodos , Vacunas Virales/inmunología , Animales , Virus de la Viruela de los Canarios/inmunología , Embrión de Pollo/citología , Pollos , Chlorocebus aethiops , Perros , Femenino , Fibroblastos/virología , Zorros/inmunología , Glicoproteínas/genética , Glicoproteínas/inmunología , Hemaglutininas Virales/genética , Hemaglutininas Virales/inmunología , Masculino , Visón/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/inmunología , Células Vero , Proteínas Virales de Fusión/genética , Proteínas Virales de Fusión/inmunología , Vacunas Virales/administración & dosificación , Vacunas Virales/genética
11.
Sci Rep ; 10(1): 9260, 2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32518298

RESUMEN

The importance of the energy exchange between the land surface and the atmosphere can be characterized by bulk transfer coefficients for momentum, Cd, and heat, Ch. The diurnal and monthly variations of both bulk transfer coefficients and lengths of surface roughness are analyzed. Based on observed data from January to December 2009 in hinterland of the Taklimakan Desert, the characteristics of aerodynamic roughness length, z0m, and thermal roughness length, z0h, are discussed. It should be noted that the diurnal and monthly variations of the parameters are fundamentally different from those reported in vegetated areas. Specifically, four unique features can be identified in the surface layer. First, in Taklimakan Desert, z0m does not vary with seasons; however, it significantly depends on wind speed. Second, z0h is higher in the daytime and lower at night, showing obvious diurnal characteristics. The high values appear at sunrise and sunset. Third, both Cd and Ch have two peaks, one peak at sunrise, and another one at noon. Fourth, both Cd and Ch have larger values in winter season and smaller values in summer season.

12.
Sci Rep ; 10(1): 81, 2020 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-31919374

RESUMEN

Climate changes significantly impact environmental and hydrological processes. Precipitation is one of the most significant climatic parameters and its variability and trends have great influences on environmental and socioeconomic development. We investigate the spatio-temporal variability of precipitation occurrence frequency, mean precipitation depth, PVI and total precipitation in China based on long-term precipitation series from 1961 to 2015. As China's topography is diverse and precipitation is affected by topography strongly, ANUSPLIN can model the effect of topography on precipitation effectively is adopted to generate the precipitation interpolation surface. Mann-Kendall trend analysis and simple linear regression was adopted to examine long-term trend for these indicators. The results indicate ANUSPLIN precipitation surface is reliable and the precipitation variation show different regional and seasonal trend. For example, there is a sporadic with decreasing frequency precipitation trend in spring and a uniform with increasing frequency trend in summer in Yangtze Plain, which may affect spring ploughing and alteration of flood risk for this main rice-production areas of China. In north-western China, there is a uniform with increasing precipitation frequency and intensity trend, which is beneficial for this arid region. Our study could be helpful for other counties with similar climate types.

13.
Sci Rep ; 9(1): 17227, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31754126

RESUMEN

Soil moisture plays an important role in land-atmosphere interactions, agricultural drought monitoring, and water resource management, particularly across arid regions. However, it is challenging to simulate soil moisture of high spatial resolution and to evaluate soil moisture at fine spatial resolution in arid regions in Northwest China due to considerable uncertainties in forcing data and limited in situ measurements. Then, the data set was used to produce the 1 km high-resolution atmospheric forcing datasets and to drive the Community Land Model version 3.5 (CLM3.5) for simulating spatiotemporally continuous surface soil moisture. The capabilities of soil moisture simulation using CLM3.5 forced by the XJLDAS-driven field were validated against data obtained at three soil layers (0-10, 0-20, and 0-50 cm) from 54 soil moisture stations in Xinjiang. Results show that the simulated soil moisture agreed well with the observations [CORR > 0.952], and the intra-annual soil moisture in Xinjiang gradually increased during May through August. The main factors that affect changes in soil moisture across the study region were precipitation and snowmelt. The overall finding of this study is that an XJLDAS, high-resolution forcing data driven CLM3.5 can be used to generate accurate and continuous soil moisture of high resolution (1km) in Xinjiang. This study can help understand the spatiotemporal features of the soil moisture, and provide important input for hydrological studies and agricultural water resources management over the arid region.

15.
Artículo en Inglés | MEDLINE | ID: mdl-30708935

RESUMEN

Urban particulate air pollution is a known cause of adverse human health effects worldwide. Urumqi is a large oasis city in which rapid urbanization has caused a series of eco-environmental problems including serious air pollution, water shortage, dense population, excess energy consumption, and the creation of an urban heat island, among others. Coal is the most important source of energy and air pollutants that are poorly dispersed into the natural surroundings are the main reasons for serious pollution in the Urumqi urban area. Using differential optical absorption spectroscopy (DOAS), aerosol levels were determined using the double optical path method. We found that aerosol concentrations in Urumqi increased rapidly in winter, and that the concentration of fine particles was much higher than that of coarse particles. The background aerosol concentration was highest in winter in the research area, and the air-flow speed had a significant impact on this because high speed surface winds that correspond to high air flows can transport the aerosol to other places. Some of the observed day-to-night differences may be caused by differing wind directions that transport air masses from different emission sources during the day and the night. Daily and seasonal differences in PM1.0 concentrations of different grades of polluted air were statistically analyzed using average daily concentration data for particles smaller than 10, 2.5 and 1.0 microns (PM10, PM2.5 and PM1.0), and meteorological observations for Urumqi, Tianshan District in 2010.


Asunto(s)
Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Estaciones del Año , Aerosoles/análisis , Contaminantes Atmosféricos/química , China , Ciudades , Monitoreo del Ambiente , Humanos , Tamaño de la Partícula , Material Particulado/química , Viento
16.
Sci Rep ; 8(1): 3639, 2018 02 26.
Artículo en Inglés | MEDLINE | ID: mdl-29483567

RESUMEN

Central Asia is a region that has a large land mass, yet meteorological stations in this area are relatively scarce. To address this data issues, in this study, we selected two reanalysis datasets (the ERA40 and NCEP/NCAR) and downscaled them to 40 × 40 km using RegCM. Then three gridded datasets (the CRU, APHRO, and WM) that were extrapolated from the observations of Central Asian meteorological stations to evaluate the performance of RegCM and analyze the spatiotemporal distribution of precipitation and air temperature. We found that since the 1960s, the air temperature in Xinjiang shows an increasing trend and the distribution of precipitation in the Tianshan area is quite complex. The precipitation is increasing in the south of the Tianshan Mountains (Southern Xinjiang, SX) and decreasing in the mountainous areas. The CRU and WM data indicate that precipitation in the north of the Tianshan Mountains (Northern Xinjiang, NX) is increasing, while the APHRO data show an opposite trend. The downscaled results from RegCM are generally consistent with the extrapolated gridded datasets in terms of the spatiotemporal patterns. We believe that our results can provide useful information in developing a regional climate model in Central Asia where meteorological stations are scarce.

17.
Sci Rep ; 7(1): 15148, 2017 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-29123164

RESUMEN

The simulation abilities of the Coupled Model Inter-comparison Project Phase 5 (CMIP5) models to the arid basin (the Tarim River Basin, TRB) and humid basin (the Yangtze River Basin, YRB) were evaluated, determining the response of precipitation to external changes over typical basins. Our study shows that the future temporal and spatial variation characteristics of precipitation are different in different regions with the CMIP5. The annual and seasonal changes in precipitation were analyzed for the RCP2.6, RCP4.5 and RCP8.5 during 2021~2100 compared to those during 1961~2005. Precipitation shows an increasing trend in the TRB, but which decreases and then increases in the YRB, with a turning point in the middle of twenty-first Century. The ranges in annual precipitation increase with the increase in the scenario emissions in the future. Note that the Tarim River Basin is more vulnerable to the impact of emissions, especially for annual or spring and winter precipitation. Based on the uncertainty of CMIP5 data, the links between future precipitation changes and the elevation and relief amplitude were evaluated. The change of precipitation decreases with elevation, relief amplitude in the TRB, while it increases with elevation but decreases with relief amplitude in the YRB.

18.
Sci Rep ; 7(1): 13286, 2017 10 16.
Artículo en Inglés | MEDLINE | ID: mdl-29038535

RESUMEN

Soil temperature plays a key role in the land surface processes because this parameter affects a series of physical, chemical, and biological processes in the soil, such as water and heat fluxes. However, observation of soil temperature is quite limited, especially at the regional scale. Therefore, this study is to investigate the spatiotemporal features of soil temperature in Xinjiang, China, using the Community Land model 3.5 (CLM3.5) with the atmospheric near-surface forcing data of the China Meteorological Administration Land Data Assimilation System (CLDAS). We use the observed soil temperature data collected from 105 national automatic stations during 2009 through 2012 in the study area to verify the simulation capability. The comparison results indicate that the CLM3.5 with the CLDAS driving field could well simulate the spatiotemporal patterns of the soil temperature at hourly, daily, and monthly time scales and at three depths (5 cm, 20 cm, and 80 cm). We also produce a soil temperature database of the region that is continuous both in time and space with high resolution (about 6.25 km). Overall, this study could help understand the regional and vertical characteristics of the soil temperature and provide an important scientific basis for other land-surface processes.

19.
Meat Sci ; 100: 139-44, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25460117

RESUMEN

This study evaluates the effects of pre-rigor temperature control on quality traits of Chinese yellow cattle M. longissimus lumborum (LL). One stepwise chilling (SC) treatment was used on one half-carcass, involved a fast chilling (-11 ± 1 °C;0.5 m/s) for 2h, then the refrigeration was stopped to hold a core temperature of 12-18 °C until 10h postmortem, followed by a 1 ± 1 °C chilling (0.5 m/s) to 48h postmortem. The other half-carcass was conventional chilled at 1 ± 1 °C (0.5 m/s) until 48h as control chilling (CC). Quality attributes were evaluated at 1, 7 and 14 days. The SC treatment resulted in decreased WBSF and increased myofibril fragmentation index compared with control. SC-treated LL at 7d postmortem had a lower WBSF than those of CC-treated at 14d. This pre-rigor temperature controlled chilling is a realistic alternative for the beef industry in China to ensure adequate tenderness and shorten aging time.


Asunto(s)
Frío , Manipulación de Alimentos/métodos , Carne/análisis , Miofibrillas , Cambios Post Mortem , Refrigeración/métodos , Estrés Mecánico , Animales , Bovinos , China , Humanos , Concentración de Iones de Hidrógeno , Músculo Esquelético , Rigor Mortis
20.
Artículo en Chino | MEDLINE | ID: mdl-23672141

RESUMEN

OBJECTIVE: To evaluate the effect of internal fixation on the stability of pedicled fascial flap and the osteogenesis of exceed critical size defect (ECSD) of bone so as to provide theory for the clinical application by the radiography and histology observation. METHODS: The ECSD model of the right ulnar midshaft bone and periosteum defect of 1 cm in length was established in 32 New Zealand white rabbits (aged 4-5 months), which were divided into group A and group B randomly (16 rabbits in each group). The composite tissue engineered bone was prepared by seeding autologous red bone marrow (ARBM) on osteoinductive absorbing material (OAM) containing bone morphogenetic protein and was used repair bone defect. A pedicled fascial flap being close to the bone defect area was prepared to wrap the bone defect in group A (control group). Titanium miniplate internal fixation was used after defect was repair with composite tissue engineered bone and pedicled fascial flap in group B (experimental group). At 2, 4, 6, and 8 weeks, the X-ray films examination, morphology observation, and histology examination were performed; and the imaging 4-score scoring method and the bone morphometry analysis was carried out. RESULTS: All rabbits survived at the end of experiment. By X-ray film observation, group B was superior to group A in the bone texture, the space between the bone ends, the radiographic changes of material absorption and degradation, osteogenesis, diaphysis structure formation, medullary cavity recanalization. The radiographic scores of group B were significantly higher than those of group A at different time points after operation (P < 0.05). By morphology and histology observation, group B was superior to group A in fascial flap stability, tissue engineered bone absorption and substitution rate, external callus formation, the quantity and distribution area of new cartilage cells and mature bone cells, and bone formation such as bone trabecula construction, mature lamellar bone formation, and marrow cavity recanalization. The quantitative ratio of bone morphometry analysis in the repair area of group B were significantly larger than those of group A at different time points after operation (P < 0.05). CONCLUSION: The stability of the membrane structure and the bone defect area can be improved after the internal fixation, which can accelerate bone regeneration rate of the tissue engineered bone, shorten period of bone defect repair, and improve the bone quality.


Asunto(s)
Regeneración Ósea , Fascia/trasplante , Fijación Interna de Fracturas , Colgajos Quirúrgicos , Ingeniería de Tejidos/métodos , Cúbito/cirugía , Animales , Médula Ósea , Trasplante de Médula Ósea , Sustitutos de Huesos , Fasciotomía , Femenino , Fijación Interna de Fracturas/instrumentación , Masculino , Conejos , Radiografía , Colgajos Quirúrgicos/irrigación sanguínea , Andamios del Tejido , Titanio , Trasplante Autólogo , Cúbito/diagnóstico por imagen , Cúbito/lesiones
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