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621.
Food sovereignty movements (FSMs) globally have sought to rearrange relations between land, power, state actions and societal forces outside the state, towards a new ideal of democratised, egalitarian and ecological food systems. The question of how best to reach this ideal has vexed movements and scholars alike, with many anti-capitalist theorists proposing that because of the historical dedication of states to maintaining unequal and unsustainable capitalist relations, change must be pursued outside and against the state rather than through it (i.e. through “autonomism”). Yet, analysis of FSMs globally shows that autonomism is relative, partial and best seen as an aspirational ideal rather than a fixed dogma. This paper deepens this insight by analysing a case within the United States where a local direct action group promoted food sovereignty by illegally occupying public land. The case shows how even apparently autonomist movements can through influence on state and societal actors contribute to state-based “policy currents” that flow in the direction of food sovereignty. This mutual codetermination by actors in and out of state institutions of the possibility and shape of “policy currents” renders state–society relations as important, even to those interested in (relative) autonomism. This paper thus leaves behind dichotomous interpretations of (and recommendations for) FSMs vis-à-vis autonomism, in order to unpack the influence (in thought) and impact (in action) of autonomist tendencies in food sovereignty construction.  相似文献   
622.
It is increasingly expected that private actors play the role as entrepreneurs and front-runners in implementing climate measures, whereas empirical studies of the position, role and engagement of private actors are scarce. Situated in the context of urban planning, a critical arena for triggering climate transitions, the aim of this paper is to explore how Swedish property developers respond to climate change. Qualitative analyses of corporate policy documents and semi-structured interviews with property developers reveal a vast divergence between the written policies, where leadership ambitions are high, and how the practice of property development is discussed in interviews. In the latter, there is little evidence of property developers pursuing a forward-looking or cutting-edge climate change agenda. Instead, they are critical of increased public regulation for climate-oriented measures. Explanations both confirm previous studies, highlighting lack of perceived customer demand, uncertainty of financial returns and limited innovations, and add new elements of place-dependency suggesting that innovative and front-runner practices can only be realized in the larger urban areas. Municipalities seeking to improve their climate-oriented profile in urban planning by involving private property developers need to develop strategies to maneuver the variance in responses to increase the effectiveness of implementation.  相似文献   
623.
人工湿地污水处理系统冬季植物的筛选与评价   总被引:16,自引:5,他引:11  
选用25种冬季湿地植物进行了污水净化潜力筛选试验,并在综合应用原有湿地植物筛选与评价体系的基础上,增加植物逆境酶和基质酶指标,对试验植物进行了聚类分析.结果表明,测试植物的根系长度、活力、叶片丙二醛含量、生长量、氮磷浓度、氮磷的积累能力、根际基质脲酶活性与磷酸酶活性均存在显著差异.采用建立的净化潜力评价体系将测试植物聚类分为3大类,第1类净化力强,植物种类有水芹、油菜、灯芯草、虎耳草、德国鸢尾、桂花和花菖蒲,第2类净化力中等,植物种类有羽衣甘蓝、金盏菊、撒金珊瑚、女贞、红甜菜、杜鹃和大叶冬青,第3类净化力弱,植物种类有白菜、五月菊、月季、金鱼草、麦冬、葱兰、熊掌木、矮牵牛、小叶冬青、香石竹和红继木.  相似文献   
624.
625.
2006年12月至2007年1月(冬季)期间,对北部湾海区的生物固氮作用进行了初步研究,结果表明:当培养时间为2 h时,水体浮游生物固氮速率最高,且固氮速率随着培养时间的延长而逐渐降低。北部湾冬季固氮速率存在周日变化,8∶10~11∶10时段内固氮速率达到最高值。10 m和30 m水深在夜间仍能检测到固氮活性,这可能是浮游生物昼夜垂直移动引起的。北部湾冬季固氮速率的范围为447.5~1447.2 pmol/(L.h),固氮速率呈现出从湾内往湾外不断增加的趋势,湾口海区(B06站)的积分固氮速率为319.5μmol/(m2.d)。B06站Fe加富实验表明,添加100 nmol/L Fe能够明显促进生物固氮作用,北部湾冬季湾口海区生物固氮作用可能受到Fe限制。  相似文献   
626.
分布于湖南东北部的石蛤蟆岩体侵位于新元古代地层中。由微细粒斑状黑云母花岗闪长岩和细粒斑状黑云母二长花岗岩等两期侵入体组成。通过锆石SHRIMP U-Pb法测得岩体侵位年龄为157±2 Ma(2σ),MSWD=0.98,成岩时代为晚侏罗世。SiO2=68.26%~68.53%,K2O/Na2O=1.37~1.59,岩石属镁质、准铝质-微过铝质、高钾钙碱性-钾玄岩系列;岩石明显富集大离子亲石元素,亏损高场强元素,Rb/Sr较低(0.40~0.56);ΣREE较高(171.48~183.81),Eu为弱负异常(δEu=0.86~0.93),(La/Yb)N=27.11~45.87;具较高的εNd值(-5.11)和高T2DM(1.63 Ga)。综合研究表明,石蛤蟆花岗岩为混合源高钾钙碱性花岗岩类(KCG),其花岗岩浆有大量幔源物质加入。讨论认为岩体形成于构造体制转换下的地球动力学背景,是造山晚期张弛作用下的产物。  相似文献   
627.
Introduction: This study explored the relationship between person–job fit and safety behavior, as well as the mediating role played by psychological safety, from the perspective of social cognitive theory and person–environment fit theory. Method: A total of 800 employees from petroleum enterprises were recruited, with cluster random sampling used to collect data in two stages. Results: The results showed that employees’ safety behavior is higher under the condition of “high person–job fit—high person–organization fit” than under that of “low person–job fit—low person–organization fit.” In other words, the more congruent the level of person–job fit and person–organization fit for a given employee, the higher their level of safety behavior. Practical Applications: Psychological safety plays a mediating role between the congruence of both person–job fit and person–organization fit and employees’ safety behavior.  相似文献   
628.
The inhibition mechanism of gas-solid inhibitors on Al dust explosion was investigated experimentally in a closed cuboid chamber. The variation of parameters concerning flame propagation characteristic and explosion severity used to reflect the synergistic inhibition effect of gas-solid inhibitors on Al dust explosion were elucidated. The results showed that flame propagation velocity and explosion overpressure were inhibited with the increase of gas-solid inhibitors. The inhibition curves of gas-solid inhibitors within the experimental range were further obtained. The reason concerning the SEEP phenomenon was revealed through the GC-MS analysis. The combustion of ammonia enhanced the explosion overpressure when solid inhibitors performed at low concentration. The gas-phase product could be regarded as the inert gas as long as enough amount of inhibitors were added. To comprehend the inhibition mechanism of gas-solid inhibitors, X-ray diffraction was applied to figure out the crystal structure of explosion residue. The results indicated that both physical and chemical inhibition effects were imposed on Al dust explosion by gas-solid inhibitors, including endothermic decomposition, dilution of oxidizer, coverage of Al dust, and scavenger of free radicals. The results of this study will provide a scientific basis for the design of inhibition technology for the dust explosion.  相似文献   
629.
简要介绍了淮安市四季青污水处理厂基本概况与主要设备,针对冬季雨雪天气及较低温度情况,对A曝与B曝所呈现的不同问题和现状进行了简述,并根据污泥负荷、效率变化等指标,得出了生物活性相对值随水温变化的曲线,同时还列举了构筑物、机械设备及仪表曾出现过的异常情况,提出了一些可行性对策与预防措施,如提前做好机械设备的维护与保养,在冬季加大A、B段污泥回流比,确保微生物处在较佳状态,从而保证出水达标。  相似文献   
630.
Beckwith–Wiedemann syndrome (BWS) is an overgrowth syndrome associated with congenital malformations and tumour predisposition. BWS results from variable mutations or epigenetic modifications of imprinted genes in the 11p15 chromosomal region. We present a fetus with mild general overgrowth and bilateral enlarged echogenic kidneys with loss of the corticomedullary differentiation in which prenatal diagnosis of BWS was suspected. The rest of the fetal anatomy and the amniotic fluid volume appeared normal. After termination of the pregnancy, molecular analysis confirmed the diagnosis of BWS by showing an isolated hypermethylation of the H19 gene. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
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