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Angela Jancius 《Ethnos》2013,78(2):213-232
Drawing from an evening of fieldwork at an eastern German Protestant churchin the rapidly deindustrialized city of Leipzig, this article finalyzes a discussion among church leaders, former ‘dissidents,’ and unemployed workers on the subject of ‘community economy’ (Gemeinschaftsökonomie), a concept people interpret to represent a potential solution to the crisis of mass unemployment. Such local debates on unemployment offer a frame for understanding the re-negotiation of labor and social welfare in eastern Germany following socialism's end. finalyzing this discussion within the context of theoretical debates on ‘civil society,’ I follow Burawoy's and Gramsci's lead in fillustrating that the imagined economic sphere of ‘community economy’ is an ideological battle ground, where hegemonic discourse supporting economic neoliberalism may be either reinforced or subverted.  相似文献   

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This review explores Rex and Moore's (1967) study of Birmingham as an enduring model of ethnic segregation, stratification, conflict and cooperation. The commentary focuses on the legacy of this research for understanding ethnic segregation, community and the city as a barometer of social change.  相似文献   

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《植物生态学报》2018,42(6):681
为了探讨植物对干旱、高温及协同胁迫的响应, 该研究以木犀(Osmanthus fragrans) ‘波叶金桂’为材料, 采用盆栽质量控水法模拟干旱胁迫(对照、轻度、中度和重度)和高温胁迫, 利用动态顶空气体循环吸附法和热脱附-气相色谱-质谱(TDS-GC-MS)联用技术对其挥发性有机化合物(VOCs)进行测定; 同时测定其非结构性碳(NSC)含量及次生代谢酶活性。结果表明: 干旱胁迫对‘波叶金桂’叶片NSC组分含量影响不显著; 可溶性糖和淀粉含量在高温胁迫下显著降低, 在协同胁迫后持续性下降, 重度协同胁迫下, 葡萄糖、果糖、蔗糖和淀粉分别比对照降低47.7%、46.4%、34.4%和38.2%。干旱胁迫和协同胁迫下3-羟基-3-甲基戊二酸单酰辅酶A还原酶(HMGR)、1-脱氧木酮糖-5-磷酸还原酶(DXR)活性表现出先上升后下降, 而脂氧合酶(LOX)活性表现出持续性上升趋势; 高温胁迫后, HMGR、DXR和LOX活性显著高于对照。干旱胁迫下萜烯类VOCs释放量表现出先上升后下降趋势, 中度干旱胁迫和高温胁迫下分别比对照高37.9%和32.3%; 协同胁迫下萜烯类释放量逐渐降低, 干旱、高温和协同胁迫诱导醛类释放量明显增加。上述结果表明: 干旱胁迫条件下, ‘波叶金桂’通过NSC进行自我渗透调节, 同时合成大量萜烯类化合物来提高抗旱性; ‘波叶金桂’调控萜烯类化合物合成以及绿叶挥发物(GLVs)的释放抵御高温胁迫; 协同胁迫下萜烯类化合物的合成途径受阻, ‘波叶金桂’提高GLVs合成与释放量抵御协同胁迫; 中度和重度协同胁迫导致‘波叶金桂’细胞膜严重受损, 自我调节能力降低。  相似文献   

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The actual evidence observed in studies of LEK (local environmental knowledge) is nearly always talk about the environment, or what we refer to as LET (local environmental talk), with the claim of studying LEK usually being built upon the implicit assumption that talk about the environment is the expression of knowledge about the environment. We suggest that it is critically important for researchers to question this assumption, especially when the distinction between LET and LEK is also emphasized by local people themselves. In the case we present here, residents of small fishing villages on the Northern Peninsula of Newfoundland are routinely skeptical about what other local residents say about the environment; that is, they engage in LES (local environmental skepticism). We suggest that paying explicit attention to LES can help distinguish LEK from LET.  相似文献   

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A recent report on trade in stag beetles and rhinoceros beetles in Japan highlights a number of issues of considerable importance for beetle conservation resulting from such trade over much of south east Asia. The popularity of these beetles has both positive and negative effects, and there is need for more effective control and monitoring of this trade to enhance positive values and reduce likely harm to species and habitats.  相似文献   

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Aims

Climate, soil water potential (SWP), leaf relative water content (RWC), stomatal conductance (gs), fruit and shoot growth, and carbohydrate levels were monitored during the 2008 and 2009 growing seasons to study the responses of ‘Gala’ and ‘Fuji’ apple trees to irrigation placement or volume.

Methods

Three irrigation treatments were imposed, conventional irrigation (CI), partial root-zone drying (PRD, 50% of CI water on one side of the root-zone, which was alternated periodically), and continuous deficit irrigation (DI, 50% of CI water on both sides of the root-zone).

Results

After each irrigation season, DI generated twice the soil water deficit (SWDint) than PRD (average of dry and wet sides) and a greater integrated leaf water deficit (LWDint) than PRD and CI. Both PRD and DI reduced gs by 9 and 15% over the irrigation period. RWC of both PRD and DI was directly related to SWP and inversely related (non-linear) to vapor pressure deficit (VPD), whereas it was unrelated to gs. Considering individual sampling days, gs of ‘Gala’ leaves was inversely related to VPD mainly until early August (fruit at cell expansion phase and high VPD), while it was directly related to VPD in September (no fruit and low VPD). On the contrary, gs of ‘Fuji’ leaves was inversely related to VPD from late August until mid October (low VPD and fruit at cell expansion phase). Fruit growth was not affected by irrigation, whereas shoot and trunk growth was reduced by DI. Irrigation induced sporadic and inconsistent changes in carbohydrate contents or partitioning, with a general tendency of DI leaves to degrade and PRD to accumulate sorbitol and sucrose in dry periods.

Conclusions

‘Gala’ trees exhibited a more conservative water use than ‘Fuji’ trees due primarily to different timing of fruit growth and crop loads. Different levels of SWDint, rather than changes in stomatal control and carbohydrate partitioning, seem to play a major role in determining a better water status in PRD than in DI trees.  相似文献   

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Three sterilized acid soils were inoculated with inocula of vesicular-arbuscular mycorrhizal fungi. Soils were limed and/or P fertilized to produce different fertility levels. Most inocula consisted of mixtures of fine + coarse type endophytes. Red clover (Trifolium pratense L.) was seeded in pots and grown in a glasshouse for 4 months. Root colonization by VAM fungi, the relative infection byGlomus tenue compared to that by coarse VAM fungi and the effect of inoculation on red clover growth and mineral nutrition (P, K, Ca and Mg) were studied. Spores were also checked and tentatively identified.Results showed that root colonization by VAM fungi was higher than 50% in most cases, the lower values being found in the soil with the highest P content. Inocula containingG. mosseae + G. tenue infected plant roots only in limed (pH>5.7) soils. A study of the relative colonization by fine and coarse endophytes showed that the competitive ability againstG. tenue followed the orderG. fasiculatum > G. mosseae > G. epigaeum > G. macrocarpum, although soil properties and fertility were crucial factors.Glomus lacteum was tentatively identified in two of the three experimental soils. The inoculum in whichGlommus tenue was most infective was also the most efficient in improving plant growth and nutrient uptake. The effect of inoculation on P and Mg uptake followed a similar pattern.  相似文献   

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The alarm response to skin extract has been well documented in fish. In response to skin extract, there is a decline in both locomotion activity and aggressive interactions. Our observation herein of these responses in the cichlid Nile tilapia, Oreochromis niloticus, confirmed the existence of the alarm response in this species. However, so far there has been a paucity of information on the autonomic correlates of this response. In this study, the ventilatory change in response to the chemical alarm cue was evaluated. This parameter was measured 4 min before and 4 min after exposure to 1 mL of either conspecific skin extract or distilled water (extract vehicle). Skin extract induced an increase in the ventilation rate, which suggested an anticipatory adjustment to potentially harmful stimuli. The chemical cue (alarm substance) also interfered with the prioritisation of responses to different environmental stimuli (stimuli filtering); this was suggested by the observation that the Nile tilapia declined to fight after exposure to a cue that indicates a risk of predation. Furthermore, histological analysis of the Nile tilapia skin revealed the presence of putative alarm substance-producing (club) cells.  相似文献   

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East Asian nations have become increasingly diverse in their ethnic composition since the 1990s. A large proportion of recent immigrants consists of women from China, Vietnam, Indonesia, Thailand and the Philippines, who migrated following their marriage to male citizens from South Korea and Taiwan. To study this new group of foreign residents, the governments of both Taiwan and South Korea have conducted national surveys since 2000. This paper conducts a content analysis of the questions of these surveys to elaborate a criticism of the ethnic statistics produced from them. These surveys provide relevant information on this group of new residents, but they also have the potential to reinforce existing negative stereotypes due to prior assumptions that shaped the content of questionnaires. The analysis reveals that the production of statistics on migrants is influenced by three ideologies: assimilation, patriarchy and nationalism.  相似文献   

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Gregory Bateson was welcomed into Biosemiotics as one of its precursors along with C. S. Peirce and Jacob von Uexküll He certainly endorsed Peirce pragmatic concern with learning as an essential characteristic of mammalian life, and also endorsed von Uexküll’s notion that the fundamental unit of animate existence is organism plus econiche. But he was at odds both with the subjectivism and with the cognitivism that connects Peirce to von Uexküll. Bateson rests his case on information theory which, he believes replaces many metaphysical notions that were the background to Peirce and von Uexküll’s approaches to ‘meaning.’ His idea of cybernetic ‘feedback’ in information circuits or networks yields a new understanding of recursiveness. Yet biofeedback in mammalian interaction had to be wrestled away from technical cybernetics and its thermodynamic rules about information, for the latter payed no attention to ‘meaning’ (“Bioentropy” section). Of the contrasts between Peirce and Bateson, the most significant is that Bateson regards ‘difference’ as primary to perception, while Peirce is concerned with continuity as primary from perception to cognition. This contrast is at the heart of Bateson’s Korzybski Lecture (see “On the Title of ‘Steps’” section), and shows how ‘difference’ in Learning develops orders and levels (see “Memory and Learning” section) leading to different categories of learning. With regard to perception, Bateson argues that the processes of perception do not bind perception to conscious awareness in any exclusive sense. Further, patterns of perception are not bounded by the skin for they include all external pathways along which information can travel. This recursive activity develops ‘agency’ (“Perception and Consciousness” section). We are ourselves interact with living mental ‘things’ but interactions with animate ‘creatura,’ is not the same as the objective interactions we purse in measuring inanimate material ‘things’ (pleroma) (“How Bioentropy Informs Bateson’s Notions of Pleroma and Creatura ” section). The grasping of context in communicative interaction, for example, is unique to creatura (“Context in Recursive Communication” section). Recognition of ‘difference’ occurs through communicative interactions and is meta-physical (without dimension). The pattern of interaction is the ‘thing,’ and ostensive aspects of communication are contextual, inclusive of all ‘external’ aspects vital for interpretation of ‘signals’ between initiators and responders to messages. Towards the end of his life, Bateson’s concerns with non-human conditions of ‘meaning’ and ‘mind’ in nature, resulted in his dropping several of the Peirce’s conditions of semiosis, as he looks at ‘meaning’ without language. He rests his method the propositional order of Peirce’s abduction rather than the latter’s full array of abduction, induction and deduction. Bateson is supported by the Biosemantics of Ruth Millikan, this paper will argue, who also believes that the derivation of meaning in animals through natural signs requires the stripping away of any ‘meaning rationalism’ (“Meaning Rationalism” section). Together they provide joint conclusions about as sign use in the ecosystems of creatura (“Conclusion” section).  相似文献   

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Spooner DE  Vaughn CC 《Oecologia》2008,158(2):307-317
The sustained decline in habitat quality and community integrity highlights the importance of understanding how communities and environmental variation interactively contribute to ecosystem services. We performed a laboratory experiment manipulating effects of acclimation temperature (5, 15, 25, and 35°C) on resource acquisition, assimilation and subsequent ecosystem services provided by eight freshwater mussel species. Our results suggest that although freshwater mussels are broadly categorized as filter feeders, there are distinct nested functional guilds (thermally tolerant and sensitive) associated with their thermal performance. At 35°C, thermally tolerant species have increased resource assimilation and higher rates of contributed ecosystem services (nutrient excretion, benthic–pelagic coupling). Conversely, thermally sensitive species have decreased assimilation rates and display an array of functional responses including increased/decreased benthic–pelagic coupling and nutrient excretion. Although thermally sensitive species may be in poorer physiological condition at warmer temperatures, their physiological responses can have positive effects on ecosystem services. We extrapolated these results to real mussel beds varying in species composition to address how shifts in community composition coupled with climate change may shift their contributed ecological services. Comparative field data indicate that two co-existing, abundant species with opposing thermal performance (Actinonaias ligamentina, Amblema plicata) differentially dominate community biomass. Additionally, communities varying in the relative proportion of these species differentially influence the magnitude (benthic–pelagic coupling) and quality (N:P excretion) of ecosystem services. As species are increasingly threatened by climate change, greater emphasis should be placed on understanding the contribution of physiological stress to the integrity and functioning of ecosystems. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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In Tanzania, a nation with a large mental health treatment gap, local stakeholders’ perspectives are critical for informing effective treatment. The practice-based perspectives of mental health providers may be particularly instructive. Existing foundational literature on the professional population in this region is scarce. We conducted semi-structured interviews with 29 mental health providers in northern Tanzania. Interviews focused on three topics: use of international diagnostic frameworks for mental illness, beliefs about causes of mental health concerns, and alternative treatments sought by clients. Interview data were coded and analyzed using consensual qualitative research and the constant comparative method. Usage of diagnostic frameworks varied widely. Providers believed frameworks accurately described many patients but neglected somatic symptoms and contained diagnoses that they had never witnessed. Providers described supernatural and spiritual attributions of mental illness as substantially impacting treatment decisions. Other notable attributions included physical illness, drug/alcohol use, and heredity. Providers reported their clients routinely sought treatment from traditional and spiritual healers prior to seeking care in the formal health system. This study builds a foundation for the ongoing development of the mental health system in northern Tanzania. Findings also support exploration of integrative models of care and task-shifting to incorporate traditional and spiritual beliefs.  相似文献   

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The effects of sublethal dosages of the chloronicotinyl insecticide imidacloprid on different strains of the tobacco whitefly, Bemisia tabaci Gennadius (Homoptera: Aleyrodidae), have been studied after leaf dip and systemic application. All bioassays were performed with the insecticide susceptible strain, SUD-S, and two Spanish biotypes, ALM-2 and LMPA-2, both resistant to conventional insecticides and with a lower susceptibility towards imidacloprid. Honeydew, excreted by all strains feeding on treated and untreated cotton leaf discs was quantified by photometric analysis of its carbohydrate content. EC50-values for the depression of honeydew excretion in female adults after systemic application of imidacloprid were calculated at 0.037 ppm, 0.027 ppm and 0.048 ppm for strains SUD-S, ALM-2 and LMPA-2, respectively, indicating no significant differences between strains in feeding behaviour throughout an 48 h testing period. Depending on the strain these EC50-values were 150- to 850-times lower than LC50-values calculated for mortality in the same bioassay. Starvation tests revealed mean survival times of >48 h for female adults placed on agar without leaf discs, indicating that sublethal dosages of imidacloprid which caused antifeedant responses, were probably not covered in common 48 h systemic bioassays, used to monitor resistance to imidacloprid. Effects of sublethal dosages on honeydew excretion after leaf dip application seem to be minor. In choice situations with systemically treated and untreated leaf discs in a single container, female adults of B. tabaci showed a clear preference for the untreated leaf discs. However, when using leaf discs treated by painting the surface with imidacloprid in the same bioassay, feeding activities on treated and untreated leaf discs were not significantly different. The results of the present study demonstrate the antifeedant properties of imidacloprid on B. tabaci, which might play an essential role after soil application or seed treatment under field conditions.  相似文献   

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