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Online hate is a topic that has received considerable interest lately, as online hate represents a risk to self-determination and peaceful coexistence in societies around the globe. However, not much is known about the explanations for adolescents posting or forwarding hateful online material or how adolescents cope with this newly emerging online risk. Thus, we sought to better understand the relationship between a bystander to and perpetrator of online hate, and the moderating effects of problem-focused coping strategies (e.g., assertive, technical coping) within this relationship. Self-report questionnaires on witnessing and committing online hate and assertive and technical coping were completed by 6829 adolescents between 12 and 18 years of age from eight countries. The results showed that increases in witnessing online hate were positively related to being a perpetrator of online hate. Assertive and technical coping strategies were negatively related with perpetrating online hate. Bystanders of online hate reported fewer instances of perpetrating online hate when they reported higher levels of assertive and technical coping strategies, and more frequent instances of perpetrating online hate when they reported lower levels of assertive and technical coping strategies. In conclusion, our findings suggest that, if effective, prevention and intervention programs that target online hate should consider educating young people about problem-focused coping strategies, self-assertiveness, and media skills. Implications for future research are discussed.
Online hate is a topic that has received considerable interest lately, as online hate represents a risk to self-determination and peaceful coexistence in societies around the globe. However, not much is known about the explanations for adolescents posting or forwarding hateful online material or how adolescents cope with this newly emerging online risk. Thus, we sought to better understand the relationship between a bystander to and perpetrator of online hate, and the moderating effects of problem-focused coping strategies (e.g., assertive, technical coping) within this relationship. Self-report questionnaires on witnessing and committing online hate and assertive and technical coping were completed by 6829 adolescents between 12 and 18 years of age from eight countries. The results showed that increases in witnessing online hate were positively related to being a perpetrator of online hate. Assertive and technical coping strategies were negatively related with perpetrating online hate. Bystanders of online hate reported fewer instances of perpetrating online hate when they reported higher levels of assertive and technical coping strategies, and more frequent instances of perpetrating online hate when they reported lower levels of assertive and technical coping strategies. In conclusion, our findings suggest that, if effective, prevention and intervention programs that target online hate should consider educating young people about problem-focused coping strategies, self-assertiveness, and media skills. Implications for future research are discussed.
Background Problem behaviour theory postulates that different forms of norm violations cluster and can be explained by similar antecedents. One such cluster may include cyberbullying and cyberhate perpetration. A potential explanatory mechanism includes toxic online disinhibition, characterised by anonymity, an inability to empathise and to recognise and interpret social cues. The current study to develop a better understanding of the relationship between cyberhate and cyberbullying to inform effective intervention and prevention efforts. Aims To test the link between cyberbullying and cyberhate and whether this relationship was moderated by toxic online disinhibition. Methods Self-report questionnaires on cyberbullying, cyberhate, and toxic online disinhibition were completed by 1,480 adolescents between 12 and 17 years old (M = 14.21 years; SD = 1.68). Results Increases in cyberbullying perpetration and toxic online disinhibition were positively related to cyberhate perpetration. Furthermore, cyberbullies reported more cyberhate perpetration when they reported higher levels of toxic online disinhibition and less frequent cyberhate perpetration when they reported lower levels of toxic online disinhibition. Conclusion The current study provides evidence of a possible link between cyberbullying and cyberhate perpetration, moderated by toxic online disinhibition. This suggests that, to be effective, prevention and intervention programmes should (i) consider the co-occurrence of varying forms of cyberaggression and (ii) consider potential effects of the online environment on aggressive online behaviour among young people.
Ziel der Arbeit ist es das für die Steuerpraxis enorm bedeutsame Instrument der tatsächlichen Verständigung dogmatisch einzuordnen und deren Kriterien herauszuarbeiten. Die tatsächliche Verständigung ist insbesondere in Verfahren der steuerlichen Betriebsprüfung und der Steuerfahndung von Bedeutung, wenn über im Nachhinein nicht erforschbare Sachverhalte aufgrund der vorhandenen Beweismittel keine zureichende Bestimmtheit erlangt werden kann. Problematisch erscheint vor diesem Hintergrund, dass die bestehenden rechtlichen Anforderungen nicht im Verhältnis zur praktischen Bedeutung des Instruments stehen und in der Folge zahlreiche offene Fragen bestehen. Insbesondere auch das Verhältnis zum Strafrecht und der dort vorherrschenden - und vom Steuerrecht abweichenden - Verfahrensgrundsätze und Beweisregelungen führen dabei zu Konflikten, welche zu lösen sind.
Zentrale Fragestellungen sind dabei, ob eine Verständigung im Besteuerungsverfahren überhaupt möglich ist und wenn ja, welche Voraussetzungen an diese zu stellen sind. Schließlich wird auch auf die Frage eingegangen, ob eine Verknüpfung dieser Verständigung mit einem Steuerstrafverfahren möglich ist.
Die Arbeit untersucht die Anforderungen, welche an eine tatsächliche Verständigung als Instrument im Besteuerungsverfahren gestellt werden. Dabei wird insbesondere auf die Zulässigkeit und die Grenzen von Verständigungen und kooperativem Verwaltungshandeln im Steuerrecht eingegangen. Diese werden anhand der verfassungsrechtlichen und abgaberechtlichen Grundlagen bestimmt. Die Entwicklung der Rechtsprechung und der Verwaltungsauffassung wird dabei nachvollzogen und unter Auswertung der hierzu ergangenen Fachliteratur gewürdigt.
Schließlich werden auch auf die Anforderungen von Verständigungen im Strafverfahren beleuchtet und die Möglichkeit untersucht inwiefern die steuerrechtliche tatsächliche Verständigung hier verwertet werden kann.
Molecular identification and functional characterization of an adenylyl cyclase from the honeybee
(2006)
Cyclic AMP (cAMP) serves as an important messenger in virtually all organisms. In the honeybee (Apis mellifera), cAMP-dependent signal transduction has been implicated in behavioural processes as well as in learning and memory. Key components of cAMP-signalling cascades are adenylyl cyclases. However, the molecular identities and biochemical properties of adenylyl cyclases are completely unknown in the honeybee. We have cloned a cDNA (Amac3) from honeybee brain that encodes a membrane-bound adenylyl cyclase. The Amac3 gene is an orthologue of the Drosophila ac39E gene. The corresponding proteins share an overall amino acid similarity of approximately 62%. Phylogenetically, AmAC3 belongs to group 1 adenylyl cyclases. Heterologously expressed AmAC3 displays basal enzymatic activity and efficient coupling to endogenous G protein signalling pathways. Stimulation of beta-adrenergic receptors induces AmAC3 activity with an EC50 of about 3.1 mu m. Enzymatic activity is also increased by forskolin (EC50 approximately 15 mu m), a specific agonist of membrane-bound adenylyl cyclases. Similar to certain biogenic amine receptor genes of the honeybee, Amac3 transcripts are expressed in many somata of the brain, especially in mushroom body neurones. These results suggest that the enzyme serves in biogenic amine signal transduction cascades and in higher brain functions that contribute to learning and memory of the bee
The present work is a case study contributing to the major planning project “Suedlink”. It is structured as follows: first, in a theoretical part, mandatory theories of social acceptance (Wüstenhagen et al., 2007), steps of participation (Münnich, 2014), and the governance theory (Benz and Dose, 2011) are elaborated. Secondly, the relevant methods are discussed. Thirdly, in a qualitative analytical part, the information that were gathered from the expert interviews are analyzed with the use of the aforementioned theories. In the fourth place, an empirical quantitative analysis of data regarding the public acceptance towards Suedlink is presented.
In this case study, with the use of qualitative and quantitative methods, two questions are answered: first, which governance aspects were relevant for the priority use of underground cables for the construction of high voltage direct current transmission lines? For this question, intensive document analysis and different expert interviews were conducted. Secondly, the central question of the present work addresses the question whether local or/and individual factors affect the public acceptance towards SüdLink. Here, in particular, it is interesting to analyze if the priority use of underground cables affected the people’s acceptance towards SuedLink. In order to respond to both questions, an online survey was conducted among citizen initiatives, district administrators, and individuals in social media during March till July 2016. Thereafter, the data was analyzed with the use of descriptive quantitative methods. The data shows, that underground cables not necessarily increase public acceptance (see also Menges and Beyer, 2013). On the contrary, individual and local criteria were relevant for the survey respondents. For example criteria such as the quality of participation, distance between home and transmission lines, and the additional financial burden (taxes, higher prices for electricity) were important for the evaluation. In addition, survey respondents who participated in citizen initiatives were more critical against the priority use of underground cables and SuedLink in general. Likewise, residential homeowners rejected every form of transmission lines.
Cenozoic magnetostratigraphy and magnetic properties of the southern Issyk-Kul basin, Kyrgyzstan
(2014)
We present paleomagnetic data from the northern flank of the Tianshan range, southeast of Lake Issyk-Kul (Kyrgyzstan). 613 cores were collected in two parallel sections with a total thickness of 960 m (Chon Kyzylsuu, CK) and 990 m Jeti Oguz, JO), as well as 48 cores at six sites in a nearby anticline. Rock magnetic analyses identify both magnetite and hematite in the fluvial-lacustrine sediments. The concentration of both minerals, the magnetite:hematite ratio, and the average magnetite grain size increase upward in both sections. Anisotropy of anhysteretic remanent magnetization defines a tectonic fabric with sub-horizontal maximum axes that parallel the strike direction together with intermediate and minimum axes that streak out about a great circle orthogonal to the maximum axes suggestive of a tectonic fabric emplaced during folding. Stepwise thermal demagnetization isolates interpretable magnetization components in 284 samples that define 26 polarity chrons in CK and 19 in JO. A positive fold test, dual polarities and systematic changes in rock-magnetic parameters with depth suggest that the high temperature magnetization component was acquired coevally with deposition. An age model based on a visual magnetostratigraphic correlation of both sections with the geomagnetic polarity time scale defines absolute ages from 26.0 to 13.3 Ma, with a fairly constant sedimentation rate of 9-10 cm/ka. A correlation based on a numerical algorithm arrives at a slightly different conclusion, with deposition ages from 25.2 to 11.0 Ma and sedimentation rates from 5 to 8 cm/ka. In comparison with sedimentation rates found at other magnetostratigraphic sections in the Tianshan realm, we infer that the sedimentary record in this part of the Issyk-Kul Basin precedes the more rapid phase of uplift of the Kyrgyz Tianshan. The onset of deposition and concomitant erosion of the adjacent Terskey Range is in good agreement with independent assessments of the exhumation history of this mountain range, with erosion increasing at 25-20 Ma and accelerating after 11-13 Ma. (C) 2014 Elsevier B.V. All rights reserved.
Animals depend on a large set of essential compounds in their food. A reduced supply of specific lipid compounds has been shown to be critical for growth, reproduction and survival of aquatic molluscs and might also be critical for terrestrial gastropods. The effects were investigated of different fatty acid and cholesterol supplies on the growth, reproduction, and survival of the land snail Arianta arbustorum. Surprisingly, differences in diet did not affect shell growth, time to reach adulthood, and reproductive traits such as the number of eggs, dry mass and volume of spermatophores. However, snails reared on low cholesterol diets and low polyunsaturated fatty acid (PUFA) diets decreased their consumption rates and had a higher mortality. Snails fed a PUFA-rich diet showed higher mating activity than snails fed a diet deficient in PUFAs. A depletion of internal PUFA reserves may affect the regulation of mating behaviour because PUFAs play an important role as precursors for signal-transduction involved in the regulation of mating and reproduction. In contrast, when the diets were deficient in cholesterol, mating activity was not affected
Animals depend on a large set of essential compounds in their food. However, not all units of food are equal from a nutritional point of view. A reduced supply of protein and calcium might be critical for the growth, reproduction and survival of herbivorous gastropods. We experimentally examined the effects of different protein and calcium supplies on the growth and survival of the land snail Arianta arbustorum. Groups of snails were reared on agar-based diets with each of three levels of protein and calcium (nine treatments). Snails fed a high-protein diet grew faster and reached adulthood earlier and at a larger adult size than snails fed intermediate and low-protein diets. Surprisingly, the calcium concentration did not affect shell growth and adult size. Snails reared on intermediate- and low-calcium diets increased their consumption rates, but, despite this compensatory feeding, these snails were unable to take up the amount of calcium required for metabolism and shell growth and had a higher mortality. The calcium deficiency could partly be mitigated by the snails' internal calcium storage and reallocation capacity. A depletion of internal calcium reserves adversely affects the entire nutrient metabolism and was the probable cause for the high mortality rates associated with the intermediate- and low calcium diets observed in the present study
Food quality effects of unsaturated fatty acids on larvae of the zebra mussel Dreissena polymorpha
(2002)
In standardized growth experiments, newly hatched larvae of the zebra mussel Dreissena polymorpha were fed diets representing different biochemical compositions. Algae that were rich in (n-3) polyunsaturated fatty acids (PUFAs), except for long-chained (.C18) PUFAs (Chlorella minutissima and Monoraphidium minutum) were of low food quality. Higher growth than on C. minutissima or M. minutum was supported by a culture of the cyanobacterium Aphanothece sp., which contained traces of a long-chained (n-3) PUFA, docosahexaenoic acid (DHA, 22 : 6n-3). The alga Isochrysis aff. galbana, which contained high amounts of the longchained (n-3) PUFAs DHA and eicosapentaenoic acid (EPA, 20 : 5n- 3), supported the highest growth. The alga Nannochloropsis limnetica, which differed from I. galbana by a defi- ciency in DHA, allowed slightly, but significantly lower, growth. Growth of larvae on N. limnetica was increased by enrichment of N. limnetica cells with a lipid extract of I. galbana, showing that larval growth on N. limnetica was limited by the deficiency of a compound that was present in I. galbana. Growth was also enhanced by feeding N. limnetica cells supplemented with DHA, but not by cells enriched with EPA, indicating that DHA was the limiting factor. We conclude that, on DHA-deficient food, the larvae of D. polymorpha were not able to sufficiently convert C18-PUFAs into long- chained (n-3) PUFAs and that the rates for elongation and desaturation of EPA into DHA limited growth.
It has been proposed that growth and reproduction of animals is frequently limited by multiple nutrients simultaneously. To improve our understanding of the consequences of multiple nutrient limitations (i.e. co-limitation) for the performance of animals, we conducted standardized population growth experiments using an important aquatic consumer, the rotifer Brachionus calyciflorus. We compared nutrient profiles (sterols, fatty acids and amino acids) of rotifers and their diets to reveal consumerdiet imbalances and thus potentially limiting nutrients. In concomitant growth experiments, we directly supplemented potentially limiting substances (sterols, fatty acids, amino acids) to a nutrient-deficient diet, the cyanobacterium Synechococcus elongatus, and recorded population growth rates. The results from the supplementation experiments corroborated the nutrient limitations predicted by assessing consumerdiet imbalances, but provided more detailed information on co-limiting nutrients. While the fatty acid deficiency of the cyanobacterium appeared to be of minor importance, the addition of both cholesterol and certain amino acids (leucine and isoleucine) improved population growth rates of rotifers, indicating a simultaneous limitation by sterols and amino acids. Our results add to growing evidence that consumers frequently face multiple nutrient limitations and suggest that the concept of co-limitation has to be considered in studies assessing nutrient-limited growth responses of consumers.
The underlying mechanisms and consequences of competition and diversity are central themes in ecology. A higher diversity of primary producers often results in higher resource use efficiency in aquatic and terrestrial ecosystems. This may result in more food for consumers on one hand, while, on the other hand, it can also result in a decreased food quality for consumers; higher biomass combined with the same availability of the limiting compound directly reduces the dietary proportion of the limiting compound. Here we tested whether and how interspecific competition in phytoplankton communities leads to changes in resource use efficiency and cellular concentrations of nutrients and fatty acids. The measured particulate carbon : phosphorus ratios (C:P) and fatty acid concentrations in the communities were compared to the theoretically expected ratios and concentrations of measurements on simultaneously running monocultures. With interspecific competition, phytoplankton communities had higher concentrations of the monounsaturated fatty acid oleic acid and also much higher concentrations of the ecologically and physiologically relevant long-chain polyunsaturated fatty acid eicosapentaenoic acid than expected concentrations based on monocultures. Such higher availability of essential fatty acids may contribute to the positive relationship between phytoplankton diversity and zooplankton growth, and may compensate limitations by mineral nutrients in higher trophic levels.
We tested the influence of two light intensities [40 and 300 μmol PAR / (m2s)] on the fatty acid composition of three distinct lipid classes in four freshwater phytoplankton species. We chose species of different taxonomic classes in order to detect potentially similar reaction characteristics that might also be present in natural phytoplankton communities. From samples of the bacillariophyte Asterionella formosa, the chrysophyte Chromulina sp., the cryptophyte Cryptomonas ovata and the zygnematophyte Cosmarium botrytis we first separated glycolipids (monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and sulfoquinovosyldiacylglycerol), phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, and phosphatidylserine) as well as non-polar lipids (triacylglycerols), before analyzing the fatty acid composition of each lipid class. High variation in the fatty acid composition existed among different species. Individual fatty acid compositions differed in their reaction to changing light intensities in the four species. Although no generalizations could be made for species across taxonomic classes, individual species showed clear but small responses in their ecologically-relevant omega-3 and omega-6 polyunsaturated fatty acids (PUFA) in terms of proportions and of per tissue carbon quotas. Knowledge on how lipids like fatty acids change with environmental or culture conditions is of great interest in ecological food web studies, aquaculture, and biotechnology, since algal lipids are the most important sources of omega-3 long-chain PUFA for aquatic and terrestrial consumers, including humans.
We tested the influence of two light intensities [40 and 300 μmol PAR / (m2s)] on the fatty acid composition of three distinct lipid classes in four freshwater phytoplankton species. We chose species of different taxonomic classes in order to detect potentially similar reaction characteristics that might also be present in natural phytoplankton communities. From samples of the bacillariophyte Asterionella formosa, the chrysophyte Chromulina sp., the cryptophyte Cryptomonas ovata and the zygnematophyte Cosmarium botrytis we first separated glycolipids (monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and sulfoquinovosyldiacylglycerol), phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, and phosphatidylserine) as well as non-polar lipids (triacylglycerols), before analyzing the fatty acid composition of each lipid class. High variation in the fatty acid composition existed among different species. Individual fatty acid compositions differed in their reaction to changing light intensities in the four species. Although no generalizations could be made for species across taxonomic classes, individual species showed clear but small responses in their ecologically-relevant omega-3 and omega-6 polyunsaturated fatty acids (PUFA) in terms of proportions and of per tissue carbon quotas. Knowledge on how lipids like fatty acids change with environmental or culture conditions is of great interest in ecological food web studies, aquaculture, and biotechnology, since algal lipids are the most important sources of omega-3 long-chain PUFA for aquatic and terrestrial consumers, including humans.
Photosynthetic acclimation of phytoplankton to lower irradiation can be met by several strategies such as increasing the affinity for light or increasing antenna size and stacking of the thylakoids. The latter is reflected by a higher proportion of polyunsaturated fatty acids (PUFAs). Additionally, photosynthetic capacity (P-max), respiratory losses, and proton leakage can be reduced under low light. Here we consider the effect of light intensity and phosphorus availability simultaneously on the photosynthetic acclimation and fatty acid composition of four phytoplankters. We studied representatives of the Chlorophyceae, Cryptophyceae and Mediophyceae, all of which are important components of plankton communities in temperate lakes. In our analysis, excluding fatty acid composition, we found different acclimation strategies in the chlorophytes Scenedesmus quadricauda, Chlamydomonas globosa, cryptophyte Cryptomonas ovata and ochrophyte Cyclotella meneghiniana. We observed interactive effects of light and phosphorus conditions on photosynthetic capacity in S. quadricauda and Cry. ovata. Cry. ovata can be characterized as a low light-acclimated species, whereas S. quadricauda and Cyc. meneghiniana can cope best with a combination of high light intensities and low phosphorus supply. Principal component analyses (PCA), including fatty acid composition, showed further species-specific patterns in their regulation of P-max with PUFAs and light. In S. quadricauda and Cyc. meneghiniana, PUFAs negatively affected the relationship between P-max and light. In Chl. globosa, lower light coincided with higher PUFAs and lower P-max, but PCA also indicated that PUFAs had no direct influence on P-max. PUFAs and P-max were unaffected by light in Cry. ovata. We did not observe a general trend in the four species tested and concluded that, in particular, the interactive effects highlight the importance of taking into account more than one environmental factor when assessing photosynthetic acclimation to lower irradiation.
The factors that determine the efficiency of energy transfer in aquatic food webs have been investigated for many decades. The plant-animal interface is the most variable and least predictable of all levels in the food web. In order to study determinants of food quality in a large lake and to test the recently proposed central importance of the long-chained eicosapentaenoic acid (EPA) at the pelagic producer-grazer interface, we tested the importance of polyunsaturated fatty acids (PUFAs) at the pelagic producerconsumer interface by correlating sestonic food parameters with somatic growth rates of a clone of Daphnia galeata. Daphnia growth rates were obtained from standardized laboratory experiments spanning one season with Daphnia feeding on natural seston from Lake Constance, a large pre-alpine lake. Somatic growth rates were fitted to sestonic parameters by using a saturation function. A moderate amount of variation was explained when the model included the elemental parameters carbon (r2 = 0.6) and nitrogen (r2 = 0.71). A tighter fit was obtained when sestonic phosphorus was incorporated (r2 = 0.86). The nonlinear regression with EPA was relatively weak (r2 = 0.77), whereas the highest degree of variance was explained by three C18-PUFAs. The best (r2 = 0.95), and only significant, correlation of Daphnia's growth was found with the C18-PUFA α-linolenic acid (α-LA; C18:3n-3). This correlation was weakest in late August when C:P values increased to 300, suggesting that mineral and PUFA-limitation of Daphnia's growth changed seasonally. Sestonic phosphorus and some PUFAs showed not only tight correlations with growth, but also with sestonic α-LA content. We computed Monte Carlo simulations to test whether the observed effects of α-LA on growth could be accounted for by EPA, phosphorus, or one of the two C18-PUFAs, stearidonic acid (C18:4n-3) and linoleic acid (C18:2n-6). With >99 % probability, the correlation of growth with α-LA could not be explained by any of these parameters. In order to test for EPA limitation of Daphnia's growth, in parallel with experiments on pure seston, growth was determined on seston supplemented with chemostat-grown, P-limited Stephanodiscus hantzschii, which is rich in EPA. Although supplementation increased the EPA content 80-800x, no significant changes in the nonlinear regression of the growth rates with α-LA were found, indicating that growth of Daphnia on pure seston was not EPA limited. This indicates that the two fatty acids, EPA and α-LA, were not mutually substitutable biochemical resources and points to different physiological functions of these two PUFAs. These results support the PUFA-limitation hypothesis for sestonic C:P < 300 but are contrary to the hypothesis of a general importance of EPA, since no evidence for EPA limitation was found. It is suggested that the resource ratios of EPA and α-LA rather than the absolute concentrations determine which of the two resources is limiting growth.
Significant seasonal variation in size at settlement has been observed in newly settled larvae of Dreissena polymorpha in Lake Constance. Diet quality, which varies temporally and spatially in freshwater habitats, has been suggested as a significant factor influencing life history and development of freshwater invertebrates. Accordingly, experiments were conducted with field-collected larvae to test the hypothesis that diet quality can determine planktonic larval growth rates, size at settlement and subsequent post-metamorphic growth rates. Larvae were fed one of two diets or starved. One diet was composed of cyanobacterial cells which are deficient in polyunsaturated fatty acids (PUFAs), and the other was a mixed diet rich in PUFAs. Freshly metamorphosed animals from the starvation treatment had a carbon content per individual 70% lower than that of larvae fed the mixed diet. This apparent exhaustion of larval internal reserves resulted in a 50% reduction of the postmetamorphic growth rates. Growth was also reduced in animals previously fed the cyanobacterial diet. Hence, low food quantity or low food quality during the larval stage of D. polymorpha lead to irreversible effects for postmetamorphic animals, and is related to inferior competitive abilities.
Species such as Dreissena polymorpha sometimes contribute substantially in the transfer of primary to secondary production. During the ontogenetic cycle, the reproductive investment of adult mussels is one of the main parameters that affect recruitment success. We studied how food quality and temperature affect the reproductive investment in term of egg mass of D. polymorpha in a lake by sampling mussels monthly from 4 m and 15 m depths. Temperature affected reproduction directly and also indirectly through the food. To assess whether temperature and/or food conditions led to the differences observed in mussels sampled from the two depths, mussels were reared in the laboratory under two different temperature regimes for 3 months, simulating the temperature of the lake at 4 m and 15 m depth. Possible effects of food quality were tested at each temperature using four diets differing in fatty acid composition. Temperature played an important role as a trigger for spawning, and the type of diet clearly affected the reproductive investment. When the heterokont chromophyte alga Nannochloropsis limnetica, which is rich in polyunsaturated fatty acids (PUFAs) and long-chained PUFAs (>C18), was fed to mussels, an increased egg mass was obtained. This result was in contrast to that found when the green alga Scenedesmus obliquus and the cyanobacterium Aphanothece sp., both of which are deficient in long-chained PUFAs, were offered as food to the mussels. Such a PUFA-dependent food quality may affect reproduction in lakes. Food quality effects vary seasonally in a lake and may be most important in summer, when low-food- quality green algae and cyanobacteria are abundant. The low biochemical quality of these blooms may affect at least the later period of gametogenesis of D. polymorpha, which reproduces from June to August.
Food quality controls egg quality of the zebra mussel Dreissena polymorpha : The role of fatty acids
(2004)
We investigated the investment of adult Dreissena polymorpha to the eggs by sampling mussels monthly from 4- and 15-m water depth. The fatty acid composition of eggs differed significantly between depths and over time. To assess whether temperature and food conditions led to the differences observed for mussels sampled from the two depths, mussels were reared in the laboratory under two different 3-month temperature regimes, simulating the temperature of the lake at 4- and 15-m depth. Possible effects of food quality were tested in each simulation using four diets differing in fatty acid composition: Cryptomonas erosa, Nannochloropsis limnetica [rich in polyunsaturated fatty acids (PUFAs) and long- chained PUFAs (.C18)], Scenedesmus obliquus, and the cyanobacterium Aphanothece sp. (deficient in long-chained PUFAs). In newly released eggs, specific (n-3) and (n-6) long-chained PUFAs increased when these fatty acids were available in the natural seston or in the laboratory diets. Mussels fed organisms deficient in long-chained PUFAs were still able to allocate arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid into eggs, which suggests that minimum levels of particular fatty acids were maintained in eggs by transfer from internal reserves of the female mussels to oocytes. In contrast to the diet, there were no effects of the temperature on the fatty acid composition of eggs.
Settlement on suitable substrata under favourable environmental conditions is an important factor for a successful recruitment of adult populations of Dreissena polymorpha. Therefore, the pattern of settlement of zebra mussel (Dreissena polymorpha) larvae at different depths was studied in Lake Constance. Maximum densities of larvae and newly settled juvenile mussels were observed at 4m depth, while only single settlement episodes were recorded at greater depths (15 m and 30 m). Temperature fluctuation was used as a surrogate parameter for internal seiches. Biotic and abiotic parameters were subjected to a principal component analysis (PCA). The tight coupling of the internal seiches, larval abundance and settlement at 4-m depth vs. the lack of coupling of the latter two variables at greater depths indicated that water currents transported settling larvae to the substrata at greater depth. Our data suggest that physical factors, such as boundary mixing and internal seiches, should be considered as sources of variability in settlement.
The factors that determine the efficiency of energy transfer in aquatic food webs have been investigated for many decades. The plant-animal interface is the most variable and least predictable of all levels in the food web. In order to study determinants of food quality in a large lake and to test the recently proposed central importance of the long-chained eicosapentaenoic acid (EPA) at the pelagic producer-grazer interface, we tested the importance of polyunsaturated fatty acids (PUFAs) at the pelagic producer-consumer interface by correlating sestonic food parameters with somatic growth rates of a clone of Daphnia galeata. Daphnia growth rates were obtained from standardized laboratory experiments spanning one season with Daphnia feeding on natural seston from Lake Constance, a large pre-alpine lake. Somatic growth rates were fitted to sestonic parameters by using a saturation function. A moderate amount of variation was explained when the model included the elemental parameters carbon (r2 = 0.6) and nitrogen (r2 = 0.71). A tighter fit was obtained when sestonic phosphorus was incorporated (r2 = 0.86). The nonlinear regression with EPA was relatively weak (r2 = 0.77), whereas the highest degree of variance was explained by three C18-PUFAs. The best (r2 = 0.95), and only significant, correlation of Daphnia's growth was found with the C18-PUFA a-linolenic acid (a-LA; C18:3n-3). This correlation was weakest in late August when C:P values increased to 300, suggesting that mineral and PUFA- limitation of Daphnia's growth changed seasonally. Sestonic phosphorus and some PUFAs showed not only tight correlations with growth, but also with sestonic alpha-LA content. We computed Monte Carlo simulations to test whether the observed effects of alpha-LA on growth could be accounted for by EPA, phosphorus, or one of the two C18-PUFAs, stearidonic acid (C18:4n-3) and linoleic acid (C18:2n-6). With >99% probability, the correlation of growth with alpha-LA could not be explained by any of these parameters. In order to test for EPA limitation of Daphnia's growth, in parallel with experiments on pure seston, growth was determined on seston supplemented with chemostat-grown, Plimited Stephanodiscus hantzschii, which is rich in EPA. Although supplementation increased the EPA content 80-800x, no significant changes in the nonlinear regression of the growth rates with alpha-LA were found, indicating that growth of Daphnia on pure seston was not EPA limited. This indicates that the two fatty acids, EPA and alpha-LA, were not mutually substitutable biochemical resources and points to different physiological functions of these two PUFAs. These results support the PUFA-limitation hypothesis for sestonic C:P < 300 but are contrary to the hypothesis of a general importance of EPA, since no evidence for EPA limitation was found. It is suggested that the resource ratios of EPA and alpha-LA rather than the absolute concentrations determine which of the two resources is limiting growth.
A significant seasonal variation in size at settlement has been observed in newly settled larvae of Dreissena polymorpha in Lake Constance. Diet quality, which varies temporally and spatially in freshwater habitats, has been suggested as a significant factor influencing the life history and development of freshwater invertebrates. Accordingly, experiments were conducted with field-collected larvae to test the proposal that diet quality can determine planktonic larval growth rates, size at settlement and subsequent post-metamorphic growth rates. Larvae were fed one of two diets or starved. One diet was composed of cyanobacterial cells, which are de; cient in polyunsaturated fatty acids (PUFAs) and the other was a mixed diet rich in PUFAs. Freshly metamorphosed animals from the starvation treatment had a carbon content per individual 70% lower than that of larvae fed the mixed diet. This apparent exhaustion of larval internal reserves resulted in a 50% reduction of the post-metamorphic growth rates. Growth was also reduced in animals previously fed the cyanobacterial diet. Hence, low food quantity or low food quality during the larval stage of D. polymorpha, lead to irreversible effects for post-metamorphic animals and are related to inferior competitive abilities.
Carbon assimilation mode in mixotrophs and the fatty acid composition of their rotifer consumers
(2009)
P>1. We examined an important ecophysiological link between the mixotrophic flagellate Chlamydomonas acidophila and its consumers, the rotifers Elosa worallii, Cephalodella sp. and Brachionus sericus, by comparing their fatty acid profiles. 2. The mixotrophic flagellate was grown under either exclusively autotrophic conditions in the light, under exclusively heterotrophic conditions in the dark with an organic carbon source (glucose), or in the light plus the organic carbon sources (=mixotrophic). 3. Under heterotrophic growth conditions, C. acidophila strongly reduced its content of the n-3 polyunsaturated fatty acid (PUFA) alpha-linolenic acid (ALA, C18:3n-3) compared with auto- and mixotrophic growth conditions. Although PUFAs with more than 18 carbon atoms were not detected in C. acidophila, significant amounts of eicosatetraenoic (ETA, 20:4n-3) and eicosapentaenoic acid (EPA, 20:5n-3) were found in three rotifer consumers. 4. Species-specific differences in the fatty acid profiles with respect to ETA, EPA and the precursor ALA were found in the rotifers: Brachionus and Cephalodella fed on the heterotrophic diets synthesised less EPA. In Elosa, smaller amounts of ALA were detected but were converted efficiently to a constant content of EPA and to an exceptionally high content of ETA. 5. Since in nature the mode of carbon assimilation among mixotrophic organisms differs, and their fatty acid composition varies depending on their mode of carbon assimilation, the availability of ALA might be critical for their consumers. An insufficient dietary supply of this precursor for the synthesis of ETA and EPA can prevent consumers from regulating their content of ETA and EPA. Therefore, observed differences in values of the latter might underly species-specific differences in the competitive capability of consumers.
In der Person von Georg Potente, der von 1902 bis 1938 in Potsdam-Sanssouci tätig war, spiegelt sich eine Entwicklung vom königlichen Ober- und Hofgärtner zum staatlichen Gartendirektor, einem schöpferisch tätigen Gartendenkmalpfleger wider. Sein Schaffen in historischen Gärten ist charakterisiert durch ein zeittypisches Spannungsfeld von kaiserlichen Aufgaben zur Neuanlage und Modernisierung einzelner Parkteile bis zu komplizierten gartendenkmalpflegerischen Wiederherstellungsarbeiten ganzer Parkbereiche. Die dabei von Potente begründete und praktizierte Herangehensweise, nach der Erforschung der Entstehungsgeschichte und der Auswertung aller historischen Pläne und Beschreibungen der Gartenanlage durch eine plangrafische Überlagerung die verschiedenen zeitlichen Zustände zu gewichten und den wiederherzustellenden Zeitstil festzulegen, begründete in den 20er Jahren des 20. Jahrhunderts die wissenschaftliche Arbeitsweise der sich entwickelnden Gartendenkmalpflege.
An investigation of the conformational landscape of 1,3-dithian-2-yl bearing porphyrins and the rotational behavior of the dithianyl substituents in meso position was carried out by variable-temperature (VT) NMR spectroscopy. Additionally, theoretical results for alternative conformations and energy barriers were obtained by molecular modeling. The study revealed different NH trans tautomers with regard to the orientation of the dithianyl ligands for the free base porphyrins 1-3. Relatively ruffled porphyrin core conformations were established for the transition states of the dithianyl rotation, resulting in a lower rotational energy barrier for the nickel(II) complex 4 compared to that of the free base systems. The data obtained and the first depiction of a rotational transition state for the rotation of bulky meso-alkyl substituents illustrate the close structural interplay between meso-alkyl substituents and the macrocycle conformation in porphyrins.
Both the stoichiometry and complex stability constants of crown ether complexes with metal ions have been determined by examining gradual changes in their diffusional behavior in nonaqueous solution. Diffusion coefficients, D, were evaluated by pulsed field gradient (PFG) NMR titration experiments whilst complex stability constants were determined by nonlinear curve-fitting procedures, D versus csol., which also allow the treatment of multiple complexation equilibria (1:1 to 1:2 stoichiometries). Differences in the diffusion coefficients of the various free crown ethers with respect to their metal ion complexes indicate great sensitivity to both conformational changes and changes in molecular size upon complexation.
The performance of organic photovoltaic blend devices is critically dependent on the polymer:fullerene interface. These interfaces are expected to impact the structural and thermal properties of the polymer with regards to the conjugated backbone planarity and transition temperatures during annealing/cooling processes. Here, we report the impact of fullerene intercalation on structural and thermal properties of poly(2,5-bis(3-tetradecylthiophen-2-yOthieno[3,2-b]thiophene (PBTTT), a highly stable material known to exhibit liquid crystalline behavior. We undertake a detailed systematic study of the extent of intercalation in the PBTTT:fullerene blend, considering the use of four different fullerene derivatives and also varying the loading ratios. Resonant Raman spectroscopy allows morphology in situ during controlled heating and cooling. We find that small fullerene molecules readily intercalate into PBTTT crystallites, resulting in a planarization of the polymer backbone, but high fullerene loading ratios or larger fullerenes result in nonintercalated domains. During cooling from melt, nonintercalated blend films are found to return to their original morphology and reproduce all thermal transitions on cooling with minimal hysteresis. Intercalated blend films show significant hysteresis on cooling due to the crystallized fullerene attempting to reintercalate. The strongest hysteresis is for intercalated blend films with excess fullerene loading ratio, which form a distinct nanoribbon morphology and exhibit a reduced geminate recombination rate. These results reveal that careful consideration should be taken during device fabrication, as postdeposition thermal treatments significantly impact the charge generation and recombination dynamics.
Norway spruce (Picea abies) is periodically attacked by the bark beetle Ips typographus and its fungal associate, Endoconidiophora polonica, whose infection is thought to be required for successful beetle attack. Norway spruce produces terpenoid resins and phenolics in response to fungal and bark beetle invasion. However, how the fungal associate copes with these chemical defenses is still unclear. In this study, we investigated changes in the phenolic content of Norway spruce bark upon E. polonica infection and the biochemical factors mediating these changes. Although genes encoding the rate-limiting enzymes in Norway spruce stilbene and flavonoid biosynthesis were actively transcribed during fungal infection, there was a significant time-dependent decline of the corresponding metabolites in fungal lesions. In vitro feeding experiments with pure phenolics revealed that E. polonica transforms both stilbenes and flavonoids to muconoid-type ring-cleavage products, which are likely the first steps in the degradation of spruce defenses to substrates that can enter the tricarboxylic acid cycle. Four genes were identified in E. polonica that encode catechol dioxygenases carrying out these reactions. These enzymes catalyze the cleavage of phenolic rings with a vicinal dihydroxyl group to muconoid products accepting a wide range of Norway spruce-produced phenolics as substrates. The expression of these genes and E. polonica utilization of the most abundant spruce phenolics as carbon sources both correlated positively with fungal virulence in several strains. Thus, the pathways for the degradation of phenolic compounds in E. polonica, initiated by catechol dioxygenase action, are important to the infection, growth, and survival of this bark beetle-vectored fungus and may play a major role in the ability of I. typographus to colonize spruce trees.
Diese Anfang 2006 fertiggestellte, nunmehr postum veröffentlichte Publikation untersucht und bewertet detailliert die Positionen zum Vertrag über eine Verfassung für Europa jener Parteien, die im Europäischen Parlament der "Konföderalen Fraktion der Vereinten Europäischen Linken/Nordische Grüne Linke" (GUE/NGL) angehören. Die Debatte zum europäischen Verfassungsvertrag zwang alle linken Parteien in einer erstmalig geführten transnationalen Debatte, ihre Haltung zur EU-Mitgliedschaft des eigenen Landes, ihre Position zum Verfassungsvertrag als solchem sowie ihre generelle Bereitschaft zu verdeutlichen, einem „anderen“ oder „besseren“ Vertrag zuzustimmen. Die Arbeit zeigt eine sehr hohe Fragmentierung der Haltung der linken Parteien zum Verfassungsvertrag und zur Mitgliedschaft ihrer Länder in der EU.
In-depth understanding of the potential implications of climate change is required to guide decision- and policy-makers when developing adaptation strategies and designing infrastructure suitable for future conditions. Impact models that translate potential future climate conditions into variables of interest are needed to create the causal connection between a changing climate and its impact for different sectors. Recent surveys suggest that the primary strategy for validating such models (and hence for justifying their use) heavily relies on assessing the accuracy of model simulations by comparing them against historical observations. We argue that such a comparison is necessary and valuable, but not sufficient to achieve a comprehensive evaluation of climate change impact models. We believe that a complementary, largely observation-independent, step of model evaluation is needed to ensure more transparency of model behavior and greater robustness of scenario-based analyses. This step should address the following four questions: (1) Do modeled dominant process controls match our system perception? (2) Is my model's sensitivity to changing forcing as expected? (3) Do modeled decision levers show adequate influence? (4) Can we attribute uncertainty sources throughout the projection horizon? We believe that global sensitivity analysis, with its ability to investigate a model's response to joint variations of multiple inputs in a structured way, offers a coherent approach to address all four questions comprehensively. Such additional model evaluation would strengthen stakeholder confidence in model projections and, therefore, into the adaptation strategies derived with the help of impact models. This article is categorized under: Climate Models and Modeling > Knowledge Generation with Models Assessing Impacts of Climate Change > Evaluating Future Impacts of Climate Change
Inhalt: Beschreibung und Klassifikation relevanter Rahmenbedingungen des Handels Auswirkungen der Rahmenbedingungen auf den innerstädtischen Handel von Potsdam Auswirkungen der Rahmenbedingungen auf die Einkaufszentren "auf der grünen Wiese" und in den Potsdamer Außenbezirken Entwicklungstendenzen für den innerstädtischen Handel und den Einkaufszentren "auf der grünen Wiese" und in den Potsdamer Außenbezirken
Unity in diversity
(2005)
This paper describes the creation and preparation of TUSNELDA, a collection of corpus data built for linguistic research. This collection contains a number of linguistically annotated corpora which differ in various aspects such as language, text sorts / data types, encoded annotation levels, and linguistic theories underlying the annotation. The paper focuses on this variation on the one hand and the way how these heterogeneous data are integrated into one resource on the other hand.
Zwischen 1990 und 1994 wurden rund 1000 Liegenschaften, die in der ehemaligen DDR von der Sowjetarmee und der NVA für militärische Übungen genutzt wurden, an Bund und Länder übergeben. Die größten Truppenübungsplätze liegen in Brandenburg und sind heute teilweise in Großschutzgebiete integriert, andere Plätze werden von der Bundeswehr weiterhin aktiv genutzt. Aufgrund des militärischen Betriebs sind die Böden dieser Truppenübungsplätze oft durch Blindgänger, Munitionsreste, Treibstoff- und Schmierölreste bis hin zu chemischen Kampfstoffen belastet. Allerdings existieren auf fast allen Liegenschaften neben diesen durch Munition und militärische Übungen belasteten Bereichen auch naturschutzfachlich wertvolle Flächen; gerade in den Offenlandbereichen kann dies durchaus mit einer Belastung durch Kampfmittel einhergehen. Charakteristisch für diese offenen Flächen, zu denen u.a. Zwergstrauchheiden, Trockenrasen, wüstenähnliche Sandflächen und andere nährstoffarme baumlose Lebensräume gehören, sind Großflächigkeit, Abgeschiedenheit sowie ihre besondere Nutzung und Bewirtschaftung, d.h. die Abwesenheit von land- und forstwirtschaftlichem Betrieb sowie von Siedlungsflächen. Diese Charakteristik war die Grundlage für die Entwicklung einer speziell angepassten Flora und Fauna. Nach Beendigung des Militärbetriebs setzte dann in weiten Teilen eine großflächige Sukzession – die allmähliche Veränderung der Zusammensetzung von Pflanzen- und Tiergesellschaften – ein, die diese offenen Bereiche teilweise bereits in Wald verwandelte und somit verschwinden ließ. Dies wiederum führte zum Verlust der an diese Offenlandflächen gebundenen Tier- und Pflanzenarten. Zur Erhaltung, Gestaltung und Entwicklung dieser offenen Flächen wurden daher von einer interdisziplinären Gruppe von Naturwissenschaftlern verschiedene Methoden und Konzepte auf ihre jeweilige Wirksamkeit untersucht. So konnten schließlich die für die jeweiligen Standortbedingungen geeigneten Maßnahmen eingeleitet werden. Voraussetzung für die Einleitung der Maßnahmen sind zum einen Kenntnisse zu diesen jeweiligen Standortbedingungen, d.h. zum Ist-Zustand, sowie zur Entwicklung der Flächen, d.h. zur Dynamik. So kann eine Abschätzung über die zukünftige Flächenentwicklung getroffen werden, damit ein effizienter Maßnahmeneinsatz stattfinden kann. Geoinformationssysteme (GIS) spielen dabei eine entscheidende Rolle zur digitalen Dokumentation der Biotop- und Nutzungstypen, da sie die Möglichkeit bieten, raum- und zeitbezogene Geometrie- und Sachdaten in großen Mengen zu verarbeiten. Daher wurde ein fachspezifisches GIS für Truppenübungsplätze entwickelt und implementiert. Die Aufgaben umfassten die Konzeption der Datenbank und des Objektmodells sowie fachspezifischer Modellierungs-, Analyse- und Präsentationsfunktionen. Für die Integration von Fachdaten in die GIS-Datenbank wurde zudem ein Metadatenkatalog entwickelt, der in Form eines zusätzlichen GIS-Tools verfügbar ist. Die Basisdaten für das GIS wurden aus Fernerkundungsdaten, topographischen Karten sowie Geländekartierungen gewonnen. Als Instrument für die Abschätzung der zukünftigen Entwicklung wurde das Simulationstool AST4D entwickelt, in dem sowohl die Nutzung der (Raster-)Daten des GIS als Ausgangsdaten für die Simulationen als auch die Nutzung der Simulationsergebnisse im GIS möglich ist. Zudem können die Daten in AST4D raumbezogen visualisiert werden. Das mathematische Konstrukt für das Tool war ein so genannter Zellulärer Automat, mit dem die Flächenentwicklung unter verschiedenen Voraussetzungen simuliert werden kann. So war die Bildung verschiedener Szenarien möglich, d.h. die Simulation der Flächenentwicklung mit verschiedenen (bekannten) Eingangsparametern und den daraus resultierenden unterschiedlichen (unbekannten) Endzuständen. Vor der Durchführung einer der drei in AST4D möglichen Simulationsstufen können angepasst an das jeweilige Untersuchungsgebiet benutzerspezifische Festlegungen getroffen werden.
The filtration rate of Daphnia galeata was determined in in situ experiments in Bautzen Reservoir and in laboratory experiments, where daphnids were exposed to filtrates that previously contained either natural phytoplankton or cultured eukaryotic algae (Scenedesmus obliquus or Asterionella formosa), respectively. Individual filtration rate (FR) was measured using fluorescent beads, taking into account ingested beads in the gut only. Compared to heated control treatments (100°C), dissolved compounds released by the nutritious cultured algae during the preconditioning phase or by the natural phytoplankton assemblages from Bautzen Reservoir strongly reduced the filtration rate of D. galeata (down to 60 %). Heating deactivated these dissolved compounds. A significant correlation was found between primary production measured in situ and the reduction of FR in the filtrate of reservoir water, indicating that extra- cellular products released during photosynthesis triggered the reduction of the filtration rate. The ratio of ingested to collected beads was used to quantify the proportion of food, which was not only collected but passed the mouth of D. galeata. The ratio of ingestion to collection was compared between filtered and unfiltered reservoir water both media identical with respect to the concentration of dissolved compounds, whereas other factors (e. g. food concentration, temperature, filtration rate) were different. The changes in this ratio between filtered and unfiltered reservoir water suggest that D. galeata is capable of a chemosensory control of the ingestion behaviour by detecting external metabolites.
Introduction:
The death of a significant person through suicide is a very difficult experience and can have long-term impact on an individual's psychosocial and physical functioning. However, there are only few studies that have examined the effects of interventions in suicide survivors. In the present study, we examine an online-group intervention for people bereaved by suicide using a group-webinar.
Methods:
The intervention was developed based on focus groups with the target group. The cognitive-behavioral 12-module webinar-based group intervention focuses on suicide bereavement-related themes such as feelings of guilt, stigmatization, meaning reconstruction and the relationship to the deceased. Further, the webinar includes testimonial videos and psychoeducation. The suicide survivors are randomized to the intervention or the waiting list in a group-cluster randomized controlled trial. Primary outcomes are suicidality (Beck Scale for Suicide Ideation) and depression (Beck Depression Inventory-II) and secondary outcomes are symptoms of prolonged grief disorder (Inventory of Complicated Grief-German Version ), posttraumatic stress disorder ( Revised Impact of Event Scale ), stigmatization (Stigma of Suicide and Suicide Survivor ) and posttraumatic cognitions (Posttraumatic Cognitions Inventory).
Discussion:
Previous studies of Internet-based interventions for the bereaved were based on writing interventions showing large treatment effects. Little is known about the use of webinars as group interventions. Advantages and challenges of this novel approach of psychological interventions will be discussed.
Web-based bereavement care
(2020)
Background:
Web-based interventions have been introduced as novel and effective treatments for mental disorders and, in recent years, specifically for the bereaved. However, a systematic summary of the effectiveness of online interventions for people experiencing bereavement is still missing.
Objective:
A systematic literature search was conducted by four reviewers who reviewed and meta-analytically summarized the evidence for web-based interventions for bereaved people.
Methods:
Systematic searches (PubMed, Web of Science, PsycInfo, PsycArticles, Medline, and CINAHL) resulted in seven randomized controlled trials (N= 1,257) that addressed adults having experienced bereavement using internet-based interventions. We used random effects models to summarize treatment effects for between-group comparisons (treatmentvs.control at post) and stability over time (postvs.follow-up).
Results:
All web-based interventions were based on cognitive behavioral therapy (CBT). In comparison with control groups, the interventions showed moderate (g= .54) to large effects (g= .86) for symptoms of grief and posttraumatic stress disorder (PTSD), respectively. The effect for depression was small (g= .44). All effects were stable over time. A higher number of treatment sessions achieved higher effects for grief symptoms and more individual feedback increased effects for depression. Other moderators (i.e.dropout rate, time since loss, exposure) did not significantly reduce moderate degrees of heterogeneity between the studies.
Limitations:
The number of includable studies was low in this review resulting to lower power for moderator analyses in particular.
Conclusions:
Overall, the results of web-based bereavement interventions are promising, and its low-threshold approach might reduce barriers to bereavement care. Nonetheless, future research should further examine potential moderators and specific treatment components (e.g.exposure, feedback) and compare interventions with active controls.
Dieser Text geht der Frage nach, wie die wissenschaftliche Auseinandersetzung mit den nationalsozialistischen Ghettos in der Zeit von 1945 bis 1960 im englischen Sprachraum betrieben wurde. Werke, die jüdisches Erleben und Handeln mitsamt der gesellschaftlichen Organisation in den Mittelpunkt rücken, sind in diesem Zeitraum deutlich stärker vertreten, als dies nach einer Lektüre der Sekundärliteratur zu erwarten wäre. Ein wissenschaftlicher Ansatz, der die Juden nicht nur als namenlose Masse von Opfern wahrnimmt, tritt also durchaus schon früh auf. Ebenso wird die Politik der jüdischen Führungsschichten, der so genannten ‚Judenräte‘, deutlich differenzierter verhandelt als vermutet; neben vernichtenden Urteilen finden sich Kontextualisierungen, die ihr Agieren aus verschiedenen Blickwinkeln beleuchten und einordnen. Auch wenn diese Forschungsanliegen zunächst nur bedingt rezipiert wurden und vor allem universitär marginal blieben, lassen sich doch von dieser Seite Traditionslinien besonders in die entstehende israelische Holocaustforschung beobachten.