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Purpose

Bio-jet fuel derived from energy crops has been promoted by governments around the world through policies such as the Carbon Offsetting and Reduction Scheme for International Aviation. The environmental impact and techno-economic analysis of bio-jet fuel are particularly pertinent to China because China is under huge pressure to reduce emissions, endeavouring to meet bio-economic goals.

Methods

An LCA study was conducted on the production of bio-jet fuel from jatropha and castor by estimating the well-to-wake emissions and its economic impact. The functional unit was 1 MJ of bio-jet fuel, and field survey data was used in inventory analysis. A scenario analysis was performed to measure diverse conditions, including the planting conditions, planting regions, allocation methods, and hydrogen sources. A techno-economic analysis that combined the production costs and co-product credits was performed to calculate the minimum bio-jet fuel selling price (MJSP) based on a plant capacity of 2400 metric tonnes of feedstock per day.

Results and discussion

Compared to the environmental impacts to the fossil jet fuel, the use of biofuel would reduce the majority environmental impacts by 36–85%, when a 1:1 displacement of fossil jet fuel is considered, though the human toxicity potential impact was 100% higher. The scenario analysis indicated that (i) planting castor in harsh and unevenly distributed conditions and jatropha in stable or fertile conditions can leverage their respective advantage; (ii) the global warming potential (GWP) from castor planting in the region of north-east China ranges from 34 to 48 g CO2 eq/MJ; (iii) the GWP produced through the steam methane reforming process can be reduced by 16–17%, using advances in technological processes. The MJSP for fuel produced from jatropha and castor under the basic scenario is estimated to be 5.68 and 4.66 CNY/kg, respectively, which falls within the current market price range of 4.5–7.5 CNY/kg.

Conclusions

Bio-jet fuel from jatropha and castor oilseeds offers potential environmental benefits if they can reduce fossil jet fuel on an energy-equivalent basis. However, these benefits are likely to be reduced by the rebound effect of the fuel market. Future research is needed to better understand the magnitude of the rebound effect in China and what policy interventions can be implemented to alleviate it. Scenario analysis demonstrated the feasibility and potential of bio-jet fuel development from multiple perspectives and technological progress are conducive to the realization of environmental protection policies.

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2.
Renal hypertrophy and extracellular matrix accumulation are early features of diabetic nephropathy. Hyperglycemia-induced oxidative stress is implicated in the etiology of diabetic nephropathy. Resveratrol has potent antioxidative and protective effects on diabetic nephropathy. We aimed to examine whether high glucose (HG)-induced NADPH oxidase activation and reactive oxygen species (ROS) production contribute to glomerular mesangial cell proliferation and fibronectin expression and the effect of resveratrol on HG action in mesangial cells. By using rat mesangial cell line and primary mesangial cells, we found that NADPH oxidase inhibitor (apocynin) and ROS inhibitor (N-acetyl cysteine) both inhibited HG-induced mesangial cell proliferation and fibronectin expression. HG-induced elevation of NADPH oxidase activity and production of ROS in mesangial cells was inhibited by apocynin. These results suggest that HG induces mesangial cell proliferation and fibronectin expression through NADPH oxidase-mediated ROS production. Mechanistic studies revealed that HG upregulated NADPH oxidase subunits p22(phox) and p47(phox) expression through JNK/NF-κB pathway, which resulted in elevation of NADPH oxidase activity and consequent ROS production. Resveratrol prevented HG-induced mesangial cell proliferation and fibronectin expression through inhibiting HG-induced JNK and NF-κB activation, NADPH oxidase activity elevation and ROS production. These results demonstrate that HG enhances mesangial cell proliferation and fibronectin expression through JNK/NF-κB/NADPH oxidase/ROS pathway, which was inhibited by resveratrol. Our findings provide novel therapeutic targets for diabetic nephropathy.  相似文献   
3.
骨形态发生蛋白1(BMP1)是一类属于虾红素家族的金属蛋白酶,它在细胞外基质的形成以及调控TGFβ信号通路的过程中发挥重要作用。BMP1基因在动物卵泡发育过程中具有不同程度表达,并以某种形式参与了动物胚胎的发生和发育过程。开展对BMP1基因的研究将有助于人们从基因角度进一步阐明动物卵泡的形成和胚胎发育的机制,对医学和畜牧业等领域将产生积极的影响。着重从BMP1基因在动物胚胎发育过程中的表达定位、功能及其机制进行综述。  相似文献   
4.
生态条件对马占相思结瘤固氮的影响   总被引:17,自引:3,他引:14  
本文研究了马占相思(Acaciamangium)结瘤固氮和生态条件的关系.结果显示.马占相思根瘤固氮活性的昼夜变化与固氮能源的供给有关,它受光、温影响较大,固氮活性昼夜变化的范围为1—5μmolC2H4·g-1freshnoduleh-1。固氮活性的季节性差异也很明显,且与温、湿度的变化关系密切,在温、湿度较好的5月—10月.固氮活性较高.为3—10μmolC2H4·g-1freshnoduleh-1.冬春的干旱和低温会影响根瘤的生长和存活.造成固氮活性降低甚至失去活性.不同年份和林地的根瘤生物量为104—625kg·ha-1,以幼林期根瘤生物量较高.多数样地的根瘤生物量在300hg·ha-1以上.随着森林生态系统的发展.根系往土层深处生长以及林下草本和灌木层的增长等原因,根瘤生物量会受影响而有所下降。施肥松土能提高根瘤生物量57—344kg·ha-1,对增加固氮量有重大意义。  相似文献   
5.
LMNA基因编码A型和C型核纤层蛋白,参与细胞核核膜的组织,影响基因组稳定性并对细胞分化产生影响。人类肿瘤中LMNA表达异常普遍存在,其突变造成多种核纤层蛋白病,如Emery-Dreifuss肌营养不良症(Emery-Dreifussmusculardystrophy,EDMD)、扩张型心肌病(dilatedcardiomyopathy,DCM)和儿童早老症(Hutchinson-Glifordprogeriasyndrome,HGPS)等。为进一步研究LMNA在细胞内的功能,本研究利用CRISPR/Cas9技术对体外培养的293T与HepG2细胞株的LMNA基因进行编辑,获得两株LMNA基因敲除(LMNA KO)的稳定细胞系。与野生型相比,LMNAKO细胞系增殖能力相对减弱,凋亡增加。同时,细胞形态上也发生显著改变,核膜凹凸不平。本研究首次报道了LMNA KO永生细胞系构建和形态研究结果,为后续LMNA基因功能研究和致病突变体研究奠定基础。  相似文献   
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Cyclodextrin has been found to be an attractive novel solubilizer due to its unique material properties. Absidia coerulea is widely used in steroid bioconversion. The effects of hydroxypropyl-β-cyclodextrin (HP-β-CD) on the growth, morphology, and steroid-converting activity of A. coerulea CICC 40302 were systematically studied. HP-β-CD affected A. coerulea growth, resulting in changes in its spore morphology and mycelial morphology. It induced an increase in the spore germination rate and a decrease in cell biomass at the stationary phase. Optical microscopy revealed that HP-β-CD altered the mycelial morphology and reduced the pellet compactness of A. coerulea. A convenient and feasible computing method was used to measure pellet compactness, and it demonstrated that the compactness degree of the pellet decreased as HP-β-CD increased, which could be attributed to the modification of the physical properties of the fermentation medium. Moreover, the changing of mycelial morphology influenced steroid-converting activity. The results showed that HP-β-CD had multiple concentration-dependent effects on A. coerulea cells. HP-β-CD in the proper concentration range holds great potential as a biocompatible solubilizer.  相似文献   
7.
Three previously undescribed chlorophenyl glycosides, (2,4,6-trichloro-3-hydroxy-5-methoxyphenyl)methyl β-D-glucopyranoside ( 1 ), (2,4-dichloro-3,5-dimethoxyphenyl)methyl 6-O-β-D-glucopyranosyl-β-D-glucopyranoside ( 2 ) and 4-chloro-3-methoxy-5-methylphenyl 6-O-(6-deoxy-β-L-mannopyranosyl)-β-D-glucopyranoside ( 3 ) were obtained from Lilium regale. The absolute configurations of these new finds were elucidated by comprehensive analyses of spectroscopic data combined with acid hydrolysis derivatization. (2,4-dichloro-3,5-dimethoxyphenyl)methyl 6-O-β-D-glucopyranosyl-β-D-glucopyranoside ( 2 ) can inhibit the proliferation of lung carcinoma A549 cells with an IC50 value of 29 μΜ.  相似文献   
8.
Immunogenic cell death (ICD) is one of the mechanisms regulating cell death, which activates adaptive immunity in immunocompetent hosts and is associated with tumor progression, prognosis and therapeutic response. Endometrial cancer (EC) is one of the most common malignancies of the female genital tract, and the potential role of immunogenic cell death-related genes (IRGs) in the tumor microenvironment (TME) remains unclear. We describe the variation of IRGs and assess the expression patterns in EC samples from The Cancer Genome Atlas and Gene Expression Omnibus cohorts. Based on the expression of 34 IRGs, we identified two different ICD-related clusters and subsequently differentially expressed genes between the two ICD-related clusters were used for the identification of two ICD gene clusters. We identified the clusters and found that alterations in the multilayer IRG were associated with patient prognosis and TME cell infiltration characteristics. On this basis, ICD score risk scores were calculated, and ICD signatures were constructed and validated for their predictive power in EC patients. To help clinicians better apply the ICD signature, an accurate nomogram was constructed. The low ICD risk group was characterized by high microsatellite instability, high tumor mutational load, high IPS score and stronger immune activation. Our comprehensive analysis of IRGs in EC patients suggested a potential role in the tumor immune interstitial microenvironment, clinicopathological features and prognosis. These findings may improve our understanding of the role of ICDs, and provide a new basis for assessing prognosis and developing more effective immunotherapeutic strategies in EC.  相似文献   
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