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991.
T. N. den Hertog M. de Jong A. J. van der Ham D. Hinton R. Reis 《Culture, medicine and psychiatry》2016,40(3):383-403
“Thinking too much”, and variations such as “thinking a lot”, are common idioms of distress across the world. The contextual meaning of this idiom of distress in particular localities remains largely unknown. This paper reports on a systematic study of the content and cause, consequences, and social response and coping related to the local terms |x’an n|a te and |eu-ca n|a te, both translated as “thinking a lot”, and was part of a larger ethnographic study among the Khwe of South Africa. Semi-structured exploratory interviews with community members revealed that “thinking a lot” refers to a common experience of reflecting on personal and interpersonal problems. Consequences were described in emotional, psychological, social, behavioral, and physical effects. Coping strategies included social support, distraction, and religious practices. Our contextualized approach revealed meanings and experiences of “thinking a lot” that go beyond a psychological state or psychopathology. The common experience of “thinking a lot” is situated in socio-political, economic, and social context that reflect the marginalized and displaced position of the Khwe. We argue that “thinking a lot” and associated local meanings may vary across settings, may not necessarily indicate psychopathology, and should be understood in individual, interpersonal, community, and socio-political dimensions. 相似文献
992.
Ruth Kevers Peter Rober Ilse Derluyn Lucia De Haene 《Culture, medicine and psychiatry》2016,40(4):620-640
In the aftermath of war and armed conflict, individuals and communities face the challenge of dealing with recollections of violence and atrocity. This article aims to contribute to a better understanding of processes of remembering and forgetting histories of violence in post-conflict communities and to reflect on related implications for trauma rehabilitation in post-conflict settings. Starting from the observation that memory operates at the core of PTSD symptomatology, we more closely explore how this notion of traumatic memory is conceptualized within PTSD-centered research and interventions. Subsequently, we aim to broaden this understanding of traumatic memory and post-trauma care by connecting to findings from social memory studies and transcultural trauma research. Drawing on an analysis of scholarly literature, this analysis develops into a perspective on memory that moves beyond a symptomatic framing toward an understanding of memory that emphasizes its relational, political, moral, and cultural nature. Post-conflict memory is presented as inextricably embedded in communal relations, involving ongoing trade-offs between individual and collective responses to trauma and a complex negotiation of speech and silence. In a concluding discussion, we develop implications of this broadened understanding for post-conflict trauma-focused rehabilitation. 相似文献
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995.
Megan B. Machmuller Jacqueline E. Mohan Jeffrey M. Minucci Carly A. Phillips Nina Wurzburger 《Biogeochemistry》2016,129(3):255-272
Climate change may affect the microbial production and temperature sensitivity of extracellular enzymes that release carbon (C) and nutrients from soil organic matter. We measured the response of six hydrolytic enzymes involved in C, nitrogen (N), and phosphorus (P) degradation to experimental warming in a mixed-deciduous forest persisting on highly-weathered Ultisols (Whitehall Forest, Georgia, US). We found that warming produced no consistent enzyme response. However, we observed significant seasonal variation in enzyme activities, temperature sensitivities and elemental enzyme ratios (C:N and C:P). Seasonal differences in enzyme activity and temperature sensitivity were best explained by soil moisture and temperature. Our results suggest that seasonal dynamics in soil microclimate, organic matter supply, and microbial demand exert more control on enzyme dynamics than does a uniform increase in soil temperature. 相似文献
996.
The rate at which catalytic capacity of microbial exo-enzymes degrades post-exudation will influence the time during which return on microbes’ investment in exo-enzyme production can be realized. Further, if exo-enzyme degradation rates vary across exo-enzymes, microbial investment returns may vary by element across time. We quantify how aging of two soil organic matter (SOM)-decaying enzymes (β-D-cellobioside, BGase; and N-acetyl-β-D-glucosaminide, NAGase) influences enzyme-substrate V max at multiple temperatures (5, 15, 25 °C), and compute how enzyme age influences relative availabilities of C and N. Both BGase and NAGase exhibited similar, exponential declines in catalytic rate with age at 25 °C (0.22 ± 0.02 and 0.36 ± 0.14 d?1, respectively). At 15 °C, NAGase exhibited exponential declines in catalytic rates with age (0.79 ± 0.31 d?1), but BGase exhibited no decline. Neither enzyme exhibited a decline in catalytic rate over 72 h at 5 °C. At 15 °C, the amount of C liberated from cellulose and chitin analogues relative to N increased, on average, by more than one order of magnitude. The ratio of C:N liberated from the two substrates remained constant across enzyme age at 25 and 5 °C, but for different reasons: no differences in decay rate across enzymes at 25 °C, and no observed decay at 5 °C. Thus, temperature-dependent decreases of catalytic activity over time may influence microbial resource allocation strategies and rates of SOM decomposition. Because the enzyme decay rates we observed differ considerably from values assumed in most models, such assumptions should be revisited when parameterizing microbial process models. 相似文献
997.
David L. Achat Laurent Augusto Anne Gallet-Budynek Denis Loustau 《Biogeochemistry》2016,131(1-2):173-202
Climate change has consequences for terrestrial functioning, but predictions of plant responses remain uncertain because of the gaps in the representation of nutrient cycles and C–N–P interactions in ecosystem models. Here, we review the processes that are included in ecosystem models, but focus on coupled C–N–P cycle models. We highlight important plant adjustments to climate change, elevated atmospheric CO2, and/or nutrient limitations that are currently not—or only partially—incorporated in ecosystem models by reviewing experimental studies and compiling data. Plant adjustments concern C:N:P stoichiometry, photosynthetic capacity, nutrient resorption rates, allocation patterns, symbiotic N2 fixation and root exudation (phosphatases, carboxylates) and the effect of root exudation on nutrient mobilization in the soil rhizosphere (P solubilization, biochemical mineralization of organic P and priming effect). We showed that several plant adjustments could be formulated and calibrated using existing experimental data in the literature. Finally, we proposed a roadmap for future research because improving ecosystem models necessitate specific data and collaborations between modelers and empiricists. 相似文献
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999.
Margaret von Faber Gerda M. van der Weele Geertje van der Geest Jeanet W. Blom Nicolette van der Zouwe Ria Reis Roos C. van der Mast Jacobijn Gussekloo 《Tijdschrift voor gerontologie en geriatrie》2016,47(6):249-257
Background
To gain new insights for support for older people with low mood, we explored the perceptions of ‘screenpositive’ older people on underlying causes and possible solutions.Design and method
We conducted two in-depth interviews with 38 participants (≥77 years) who screened positive for depressive symptoms in general practice. To investigate the influence of the presence of complex health problems, we included 19 persons with and 19 without complex problems. Complex problems were defined as a combination of functional, somatic, psychological or social problems.Results
All participants used several cognitive, social or practical coping strategies. Four patterns emerged: mastery, acceptance, ambivalence, and need for support. Some participants, especially those with complex problems, were ambivalent about possible interventions.Conclusion
Most older participants perceived their coping strategies as sufficient. General practitioners can support self-management by exploring the (effectiveness of) personal coping strategies, providing information, elaborating on perceptions of risks and discussing alternative options with older persons.1000.
The rates of mineralization processes influence C sequestration and soil fertility, but despite their importance for ecosystem functioning, C, N and P net mineralization rates are seldom investigated together. Hence, we studied the relationships between net mineralization rates and organic matter stoichiometry in an 8-week incubation experiment with Oi, Oe and Oa horizon material of six beech, one spruce and one pine site. We determined C, N and P net mineralization rates, organic C quality and C:N:P stoichiometry. Net N mineralization only occurred below molar organic matter C:N ratios of 40 (Oi) or 28 (Oa) and N:P ratios of 42 (Oi) or 60 (Oa), and increased with decreasing C:N and N:P ratios. Net P mineralization only occurred below C:P ratios of 1400 (Oi) and N:P ratios of 40 (Oi), and increased with decreasing C:P and N:P ratios. Net N and P mineralization were strongly positively correlated with each other (r = 0.64, p < 0.001), whereas correlations of both net N and net P mineralization with C mineralization were weak. The average C:N:P stoichiometry of net mineralization was 620:4:1 (beech, Oi), 15,350:5:1 (coniferous, Oi), 1520:8:1 (Oe) and 2160:36:1 (Oa). On average, ratios of C:N net mineralization were higher, and ratios of N:P net mineralization lower than organic matter C:N and N:P ratios. This difference contributed to the decrease of C:N ratios and increase of N:P ratios from the Oi to the Oa horizons. In conclusion, the study shows that C, N and P net mineralization rates were closely correlated with the organic matter stoichiometry and that these correlations were modified by the degree of decomposition of the organic matter. 相似文献