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Crop byproducts can be supplemented in livestock feeds to improve the utilization of resources and reduce greenhouse gas (GHG) emissions. We explored the mitigation potential of GHG emissions by supplementing crop byproducts in feeds based on a typical intensive dairy farm in China. Results showed that GHG emissions associated with production of forage were significantly decreased by 25.60 % when no GHG emissions were allocated to crop byproducts, and enteric methane emission was significantly decreased by 13.46 % on the basis of CO2 eq, g/kg fat and protein corrected milk. The supplementation did not affect lactation performance, rumen microbiota and microbial enzymes at the gene level. Metabolomics analysis revealed changes in amino acid catabolism of rumen fluid, which were probably responsible for more propionate production. In conclusion, supplementing crop byproducts in feeds can be a potential strategy to reduce GHG emissions of livestock.
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Gases de Efecto Invernadero , Animales , Femenino , Gases de Efecto Invernadero/análisis , Gases de Efecto Invernadero/metabolismo , Ganado , Leche/química , Suplementos Dietéticos/análisis , Alimentación Animal/análisis , Metano/análisis , Efecto InvernaderoRESUMEN
The classification of individual tree species (ITS) is beneficial to forest management and protection. Previous studies in ITS classification that are primarily based on airborne LiDAR and aerial photographs have achieved the highest classification accuracies. However, because of the complex and high cost of data acquisition, it is difficult to apply ITS classification in the classification of large-area forests. High-resolution, satellite remote sensing data have abundant sources and significant application potential in ITS classification. Based on Worldview-3 and Google Earth images, convolutional neural network (CNN) models were employed to improve the classification accuracy of ITS by fully utilizing the feature information contained in different seasonal images. Among the three CNN models, DenseNet yielded better performances than ResNet and GoogLeNet. It offered an OA of 75.1% for seven tree species using only the WorldView-3 image and an OA of 78.1% using the combinations of WorldView-3 and autumn Google Earth images. The results indicated that Google Earth images with suitable temporal detail could be employed as auxiliary data to improve the classification accuracy.
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Tecnología de Sensores Remotos , Árboles , Bosques , Redes Neurales de la Computación , Estaciones del AñoRESUMEN
In this work, we report the fabrication of nonvolatile memory devices based on chemical vapor deposition-grown copper polyphthalocyanine (CuPPc) thin films. The high polymerization degree and crystallinity of the as-obtained films were confirmed by transmission electron microscopy, X-ray photoelectron spectroscopy, and UV-vis studies. It was found that the device with Au/CuPPc/indium tin oxide sandwich structure exhibits good nonvolatile memory performance with a large ON/OFF current ratio of 103 and long retention time of 1.2 × 103 s.
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This study aimed to investigate the developmental potential of and the ultrastructural changes and gene expression differences resulting from liquid helium (LHe; -269 °C) vitrification in immature bovine oocytes. Immature oocytes were randomly divided into three groups: fresh oocytes (control, negative control), oocytes vitrified in liquid nitrogen (LN group, positive control), and oocytes vitrified in LHe (LHe group). In experiment 1, the rates of normal morphology, maturation, cleavage, and blastocyst in the LHe group were higher than those in the LN group (87.1% vs. 80.5%, 51% vs. 48%, 41.7% vs. 36.8%, and 13% vs. 8.5%, respectively; P < 0.05), and the rates of development in the control group (100%, 73.2%, 62%, and 39.8%) were higher than those in the treated groups (P < 0.05). In experiment 2, oocytes displayed various degrees of injury at the ultrastructural level after vitrification, but more severe degeneration was observed in the LN group, such as formation of several lipid droplets, swelling of mitochondria, and absence of cortical granules. Compared with the LN group, fewer lipid droplets, relatively intact mitochondria, and clustered cortical granules were distributed in the cytoplasm of oocytes in the LHe group. In experiment 3, the mRNA expression levels of p53, CDC20, Eg5, and Npm2 were investigated by real-time quantitative polymerase chain reaction. Expression levels of the kinesin Eg5 and the apoptotic gene p53 expression levels were higher in the LN group compared with the control and LHe groups (P < 0.05). CDC20 and Npm2 expression did not differ significantly between the LN and LHe groups (P > 0.05), the CDC20 expression in the LN and LHe groups were lower than control group (P < 0.05), the Npm2 expression in LHe group was lower than control group (P < 0.05), but there was no significant difference between the LN and control groups (P > 0.05). In conclusion, LHe vitrification decreased the negative effect of cryoinjury on the ultrastructure of some organelles and the expression of some related genes, thereby improving the viability of immature bovine oocytes compared to LN vitrification.
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Bovinos/fisiología , Criopreservación/veterinaria , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Oocitos/fisiología , Oocitos/ultraestructura , Vitrificación , Animales , Células del Cúmulo/fisiología , Femenino , Regulación de la Expresión Génica/fisiología , Helio , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
The objectives of this study were to compare the effectiveness of liquid helium (LHe) and liquid nitrogen (LN2) as cryogenic liquid for vitrification of bovine immature oocytes with open-pulled straw (OPS) system and determine the optimal cryoprotectant concentration of LHe vitrification. Cumulus oocyte complexes were divided into three groups, namely, untreated group (control), LN2 vitrified with OPS group, and LHe vitrified with OPS group. Oocyte survival was assessed by morphology, nuclear maturation, and developmental capability. Results indicated that the rates of normal morphology, maturation, cleavage, and blastocyst (89.3%, 52.8%, 42.7%, and 10.1%, respectively) in the LHe-vitrified group were all higher than those (79.3%, 43.4%, 34.1%, and 4.7%) in the LN2-vitrified group (P < 0.05) although the corresponding rates in both treated groups decreased compared with the control group (100%, 75.0%, 64.9%, and 40.8%; P < 0.05). Normal calves were obtained after the transfer of blastocysts derived from LHe- and LN2-vitrified oocytes. The effects of the different vitrification solutions (EDS30, EDS35, EDS40, EDS45, and EDS50) in LHe vitrification for bovine immature oocytes vitrification were examined. No difference was found in the rates of morphologically normal oocytes among the EDS30 (87.9%), EDS35 (90.1%), EDS40 (89.4%), and EDS45 (87.2%) groups (P > 0.05). The maturation rate of the EDS35 group (65.0%) was higher than those of the EDS30 (51.3%), EDS40 (50.1%), EDS45 (52.1%), and EDS50 groups (36.9%; P < 0.05). No significant differences were observed in the cleavage and blastocyst rates between the EDS35 (49.0% and 12.1%) and EDS40 (41.7% and 10.2%) groups. However, the cleavage and blastocyst rates in the EDS35 group were higher (P < 0.05) than those of the EDS30 (36.2% and 6.8%), EDS45 (35.9% and 5.8%), and EDS50 (16.6% and 2.2%) groups. In conclusion, LHe can be used as a cryogenic liquid for vitrification of bovine immature oocytes, and it is more efficient than LN2-vitrified oocytes in terms of blastocyst production. EDS35 was the optimal cryoprotectant agent combination for LHe vitrification in this study.
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Criopreservación/veterinaria , Helio , Nitrógeno , Oocitos , Animales , Bovinos , Técnicas de Cultivo de Célula/veterinaria , Criopreservación/métodos , Técnicas de Maduración In Vitro de los Oocitos/veterinaria , Técnicas Reproductivas Asistidas/veterinaria , VitrificaciónRESUMEN
Previous studies showed that several miRNAs can regulate pathways involved in UVB-induced premature senescence and response to ultraviolet irradiation. It has also been reported that miR-34c-5p may be involved in senescence-related mechanisms. We propose that miR-34c-5p may play a crucial role in senescence of normal human primary dermal fibroblasts. Here, we explored the roles of miR-34c-5p in UVB-induced premature senescence on dermal fibroblasts. MiR-34c-5p expression was increased in dermal fibroblasts after repeated subcytotoxic UVB treatments. Underexpression of miR-34c-5p in dermal fibroblasts led to a marked delay of many senescent phenotypes induced by repeated UVB treatments. Furthermore, underexpression of miR-34c-5p in dermal fibroblasts can antagonize the alteration of G1-arrested fibroblasts. Moreover, E2F3, which can inactivate p53 pathway and play a role in cell cycle progression, is a down-stream target of miR-34c-5p. Forced down-expression of miR-34c-5p decreased the expression of UVB-SIPS induced P21 and P53 at both mRNA and protein levels. Our data demonstrated that down-regulation of miR-34c-5p can protect human primary dermal fibroblasts from UVB-induced premature senescence via regulations of some senescence-related molecules.
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Senescencia Celular/efectos de la radiación , Fibroblastos/efectos de la radiación , MicroARNs/fisiología , Rayos Ultravioleta , Células Cultivadas , Senescencia Celular/genética , Niño , Regulación hacia Abajo , Factor de Transcripción E2F3/biosíntesis , Fibroblastos/citología , Humanos , Masculino , MicroARNs/metabolismo , Piel/citología , Piel/efectos de la radiación , Proteína p53 Supresora de Tumor/biosíntesis , Quinasas p21 Activadas/biosíntesisRESUMEN
The aim of this study was to assess the effects of ultraviolet B (UVB) irradiation on microRNA (miRNA) expression in normal human keratinocytes. Global miRNA expression profiles of primary cultures of normal human keratinocytes 4 and 24 h postirradiation were studied using miRNA microarray with further confirmation by real-time PCR. We found that upon 30 or 60 mJ/cm(2) of UVB radiation, the expression of 44 miRNAs was up- or downregulated more than twofold compared with non-irradiated keratinocytes. MiRNAs were either up- or downregulated after 4 h and then either returned to normal levels or remained affected after 24 h, resulting in four distinct patterns of miRNA expression change. It appears that acute exposure of keratinocytes to UVB radiation results in several specific patterns of miRNA response.