Our agrifood systems require transformation to meet today’s challenges, especially the growing demand for protein. Promising alternative protein sources include algae, crickets and jellyfish, but little is known how the public perceives these future options. We argue that to identify responsible pathways for the protein transitions, the public’s views need to be explored. Consequently, the aim of this study was to understand public perceptions of three alternative future pathways for protein transition. Our survey of 474 respondents in Germany showed that the consumption of algae in the future is perceived as possible and more probable than the consumption of animal-based sources of proteins such as cricket and jellyfish. Gender, age, geographical location and food habits were found to influence these perceptions. Reflecting on the differences in the public perceptions of three alternative protein sources, we discuss how inclusive these future visions are and how to manage the innovation and transition responsibly.
Weniger anzeigenBased on six newsroom surveys, this article analyzes the history of digital German journalism. The surveys cover a period of 17 years (1997–2014). Periodizing the history of digital journalism into three phases, this article considers the interplay between journalism and journalism research. The results show how journalistic digital media define their role in the relationships between old media and the Internet, digital media and other outlets, and digital media and their audiences. Furthermore, the results substantiate how digital editorial staff define their journalistic identities regarding tasks, rules, and skills. During the first period (surveys conducted in 1997 and 2000), the view from old mass media to the Internet dominated, also in scholarship where the mass media paradigm was extended to the Internet. The second period (surveys conducted in 2006 and 2007) was characterized by clarifying the relationships between journalism and newly emerged outlets. These studies focused on how participative formats (such as Wikipedia and blogs) and search engines could be used for journalistic purposes without compromising quality. These new outlets were not regarded then as much of a threat. This attitude did not change during the third period (surveys conducted in 2010 and 2014). In this phase, too, the studies focused on how editorial staff utilized the ever-increasing number of social media. The six surveys’ different research interests reveal that the reviewed journalism research primarily addressed changing demands in journalistic practice. Therefore, exogenous factors (“the sector”) had a greater impact than endogenous factors (the “scholarship”) on research interests.
Weniger anzeigenWe investigate the magneto-optical response of Co to an ultrashort laser excitation by x-ray resonant magnetic reflectivity (XRMR) employing circular polarization. The time-resolved reflectivities detected for opposite sample magnetization are separated into magnetic and nonmagnetic contributions, which contain information about the structural, electronic, and magnetic properties of the sample. Different response times of the different contributions are observed. The experimental results are reproduced numerically by two different simulation approaches. On the one hand, we use a purely thermal model, a time-dependent heat-induced loss of macroscopic magnetization, and an inhomogeneous laser-induced strain profile. On the other hand, we employ time-dependent density-functional theory to calculate the transient optical response to the laser-induced excitation and from that the reflected intensities. While both methods are able to reproduce the time dependence of the magnetic signal, the ultrafast nonmagnetic change in reflectivity is captured satisfactorily only in simulations of the transient optical response function and has thus to be assigned to electronic effects. The energy dependence of the magnetic circular dichroism is investigated in the simulations, highlighting a dependence of the observable on the probing energy. Finally, a phenomenological explanation of the dynamics measured in dichroic x-ray reflectivity in the different channels is offered.
Weniger anzeigenThe Simons process is an electrochemical fluorination method to prepare organofluorine compounds. Despite the wide application, the underlying mechanism is still unclear. We report the investigation of the black film formed on the surface of the anodes in aHF by an in situ Ni K-edge X-ray absorption near edge structure (XANES) investigation. An electrochemical cell for in situ X-ray absorption spectroscopy (XAS) is presented.
The ultrafast and element-specific response of magnetic systems containing ferromagnetic 3d transition metals and 4d/5d heavy metals is of interest both from a fundamental as well as an applied research perspective. However, to date no consensus about the main microscopic processes describing the interplay between intrinsic 3d and induced 4d/5d magnetic moments upon femtosecond laser excitation exist. In this work we study the ultrafast response of CoFeB/Pt bilayers by probing element-specific, core-to-valence-band transitions in the extreme ultraviolet spectral range using high harmonic radiation. We show that the combination of magnetic scattering simulations and analysis of the energy- and time-dependent magnetic asymmetries allows us to accurately disentangle the element-specific response in spite of overlapping Co and Fe M2,3 as well as Pt O2,3 and N7 resonances. We find a considerably smaller demagnetization time constant as well as much larger demagnetization amplitudes of the induced moment of Pt compared to the intrinsic moment of CoFeB. Our results are in agreement with enhanced spin-flip probabilities due to the high spin-orbit coupling localized at the heavy metal Pt, as well as with the recently formulated hypothesis that a laser-generated, incoherent magnon population within the ferromagnetic film leads to an overproportional reduction of the induced magnetic moment of Pt.
Weniger anzeigenBifurcating electron transferring flavoproteins (Bf-ETFs) tune chemically identical flavins to two contrasting roles. To understand how, we used hybrid quantum mechanical molecular mechanical calculations to characterize noncovalent interactions applied to each flavin by the protein. Our computations replicated the differences between the reactivities of the flavins: the electron transferring flavin (ETflavin) was calculated to stabilize anionic semiquinone (ASQ) as needed to execute its single-electron transfers, whereas the Bf flavin (Bfflavin) was found to disfavor the ASQ state more than does free flavin and to be less susceptible to reduction. The stability of ETflavin ASQ was attributed in part to H-bond donation to the flavin O2 from a nearby His side chain, via comparison of models employing different tautomers of His. This H-bond between O2 and the ET site was uniquely strong in the ASQ state, whereas reduction of ETflavin to the anionic hydroquinone (AHQ) was associated with side chain reorientation, backbone displacement, and reorganization of its H-bond network including a Tyr from the other domain and subunit of the ETF. The Bf site was less responsive overall, but formation of the Bfflavin AHQ allowed a nearby Arg side chain to adopt an alternative rotamer that can H-bond to the Bfflavin O4. This would stabilize the anionic Bfflavin and rationalize effects of mutation at this position. Thus, our computations provide insights on states and conformations that have not been possible to characterize experimentally, offering explanations for observed residue conservation and raising possibilities that can now be tested.
Weniger anzeigenInterfaces of dye molecules and two-dimensional transition metal dichalcogenides (TMDCs) combine strong molecular dipole excitations with high carrier mobilities in semiconductors. Förster type energy transfer is one key mechanism for the coupling between both constituents. We report microscopic calculations of a spectrally resolved Förster induced transition rate from dye molecules to a TMDC layer. Our approach is based on microscopic Bloch equations which are solved self-consistently together with Maxwell's equations. This approach allows to incorporate the dielectric environment of a TMDC semiconductor, sandwiched between donor molecules and a substrate. Our analysis reveals transfer rates in the meV range for typical dye molecules in closely stacked structures, with a nontrivial dependence of the Förster rate on the molecular transition energy resulting from unique signatures of dark, momentum forbidden TMDC excitons.
Weniger anzeigenThe presence of pathogens, e.g., Escherichia coli (E. coli), in chicken manure can potentially lead to serious infections and foodborne diseases when spread on land as organic fertilizer. Therefore, it is essential to inactivate these bacteria before land application. The aim of the present study was to determine the survival of E. coli and the temperature development in compost piles during composting of chicken manure with a typically low carbon/nitrogen (C/N) ratio and moisture content (MC). In a summer and winter trial, chicken manure piles were stacked in 1) uncovered static piles, 2) covered static piles, and 3) periodically turned piles. Samples were inoculated with a nonpathogenic E. coli strain at levels of 107 cfu/g and placed at subsurface and center locations of the piles. Within 24 h, E. coli were undetectable by direct count in all piles and at all sample locations. By d 28, all samples were also negative for E. coli by enrichment. Despite the suboptimal composting conditions with an initial C/N ratio of 10:1 and an MC below 40%, temperatures within all piles mainly exceeded 50°C within the first 24 h. Statistical analyses showed that the sample location and the total hours at temperatures ≥50 and 55°C in the piles had significant influences on the survival of E. coli in the chicken manure compost. The season and manure treatment method had no significant effects on the presence of E. coli.
Weniger anzeigenBACKGROUND: The Pavlovian-to-instrumental transfer (PIT) paradigm measures the effects of Pavlovian conditioned cues on instrumental behavior in the laboratory. A previous study conducted by our research group observed activity in the left nucleus accumbens (NAcc) elicited by a non–drug-related PIT task across patients with alcohol dependence (AD) and healthy control subjects, and the left NAcc PIT effect differentiated patients who subsequently relapsed from those who remained abstinent. In this study, we aimed to examine whether such effects were present in a larger sample collected at a later date.
METHODS: A total of 129 recently detoxified patients with AD (21 females) and 74 healthy, age- and gender-matched control subjects (12 females) performing a PIT task during functional magnetic resonance imaging were examined. After task assessments, patients were followed for 6 months. Forty-seven patients relapsed and 37 remained abstinent.
RESULTS: We found a significant behavioral non–drug-related PIT effect and PIT-related activity in the NAcc across all participants. Moreover, subsequent relapsers showed stronger behavioral and left NAcc PIT effects than abstainers. These findings are consistent with our previous findings.
CONCLUSIONS: Behavioral non–drug-related PIT and neural PIT correlates are associated with prospective relapse risk in AD. This study replicated previous findings and provides evidence for the clinical relevance of PIT mechanisms to treatment outcome in AD. The observed difference between prospective relapsers and abstainers in the NAcc PIT effect in our study is small overall. Future studies are needed to further elucidate the mechanisms and the possible modulators of neural PIT in relapse in AD.
Weniger anzeigenIn chickens, γδ T cells represent a large fraction of peripheral T cells; however, their function remains largely unknown. Here, we describe the selective in vitro expansion of γδ T cells from total splenocytes by stimulation with the cytokines IL-2 and IL-12. Under these conditions, γδ T cells proliferated preferentially and reached frequencies of >95% within three weeks. Although IL-2 alone also triggered proliferation, an increased proliferation rate was observed in combination with IL-12. Most of the expanded cells were γδ TCR and CD8 double-positive. Splenocytes sorted into TCR1+CD8+, TCR1highCD8−, and TCR1lowCD8− subsets proliferated well upon dual stimulation with IL-2/IL-12, indicating that none of the three γδ T cell subsets require bystander activation for proliferation. TCR1+CD8+ cells maintained CD8 surface expression during stimulation, whereas CD8− subpopulations showed varied levels of CD8 upregulation, with the highest upregulation observed in the TCR1high subset. Changes in the γδ T-cell receptor repertoire during cell culture from day 0 to day 21 were analyzed by next-generation sequencing of the γδ variable regions. Overall, long-term culture led to a restricted γ and δ chain repertoire, characterized by a reduced number of unique variable region clonotypes, and specific V genes were enriched at day 21. On day 0, the δ chain repertoire was highly diverse, and the predominant clonotypes differed between animals, while the most frequent γ-chain clonotypes were shared between animals. However, on day 21, the most frequent clonotypes in both the γ and δ chain repertoires were different between animals, indicating that selective expansion of dominant clonotypes during stimulation seems to be an individual outcome. In conclusion, IL-2 and IL-12 were sufficient to stimulate the in vitro outgrowth of γδ T cells. Analyses of the TCR repertoire indicate that the culture leads to an expansion of individual T cell clones, which may reflect previous in vivo activation. This system will be instrumental in studying γδ T cell function.
Weniger anzeigenDespite two centuries of fossils collecting, no cetacean remains from the Oligocene marine deposits of the Mainz Basin (western Germany) have ever been reported. Here, we describe a possible mysticete tooth from the sand pit of Eckelsheim, which exposes high energy deposits belonging to the Rupelian Alzey Formation. The latter has yielded a rich assemblage of vertebrates and invertebrates, but so far, only one marine mammal in the form of the sirenian Kaupitherium. The whale tooth in some ways resembles the m2 of Llanocetus from the latest Eocene of Seymour Island, Antarctica. If the find from the Mainz Basin is not a regionally evolved form, Llanocetus, which is known from the South Atlantic, could have migrated through the Atlantic realm during the early Oligocene. It cannot be excluded that the tooth represents a more widely occurring lineage, neither endemic nor necessarily related to llanocetids, that—given the generally poor Rupelian record—has not been well documented yet.
Weniger anzeigenTransition metal dichalcogenide (TMD) materials attract significant research attention thanks to their exceptional excitonic and optical properties. In this work, we analyze the formation of strained ultrasharp zigzag edges in MoS2 multilayers produced by anisotropic wet etching. The topography of the edges is determined by the relative stability of the different crystallographic directions of the multilayer as well as the interlayer interactions. Furthermore, we study the linear (Raman) and nonlinear (second-harmonic generation) spectroscopic characteristics of such edges and observe enhanced second-order nonlinearity originating from the strained zigzag edges. We also confirm that ultrasharp hexagonal nanoholes in MoS2 grow along the most stable crystallographic directions despite potential stacking faults or instabilities in the crystal quality. Our results open the way to exploit a broad range of phenomena occurring at the edges of MoS2 material, including the unique determination of crystal orientation for moiré engineering and strongly correlated phenomena in 2D material-based systems, as well as potential applications in TMD-based electrocatalysis and gas sensing.
Weniger anzeigenIn addition to the whole white-flowered pea, pea protein concentrates and pea hulls can be utilized in animal nutrition. In particular, fermentable carbohydrates and fibers in peas and pea products seem to contribute to intestinal health and health maintenance in poultry, due to their prebiotic effect on the intestinal microbiota. This study was conducted to investigate the effect of different proportions of peas (P), pea protein concentrate (PPC) and pea hulls (PH) in complete feed mixtures for broilers on growth and slaughter performance as well as intestinal microbiota. Twenty diets with varying proportions of peas and pea products were fed to male broilers from d 1 to 34. Short-chain fatty acid analysis and 16S sequencing were used to examine the ileal and cecal microbiota for selected feeding groups. Overall, the attained fattening performances were at a high level. The use of peas and pea products did not affect body weight on d 34 or slaughter performance. The use of pea hulls up to 6% resulted in the highest overall feed intake and overall feed conversion ratio (P < 0.001). Microbiota composition and ileal bacterial metabolites were unchanged. Microbiota changes in the cecum were found between dietary treatments for several subdominant microbial genera that preferentially ferment carbohydrates. This study has shown that peas and pea products are well-suited as feedstuffs for feeding broilers when used appropriately. Furthermore, the intestinal microbiota responded with an increased abundance of nonpathogenic genera that may help maintain intestinal microbial homeostasis.
Weniger anzeigenDespite the variety of pathogens that are transmitted via the airborne route, few data are available on factors that influence the tenacity of airborne pathogens. In order to better understand and thus control airborne infections, knowledge of these factors is important. In this study, three agents, S. aureus, G. stearothermophilus spores and the MS2 bacteriophage, were aerosolized at relative humidities (RH) varying between 30% and 70%. Air samples were then analyzed to determine the concentration of the agents. S. aureus was found to have significantly lower survival rate in the aerosol at RH above 60%. It showed the lowest recovery rates of the three agents, ranging from 0.13% at approximately 70% RH to 4.39% at 30% RH. G. stearothermophilus spores showed the highest tenacity with recovery rates ranging from 41.85% to 61.73% with little effect of RH. For the MS2 bacteriophage, a significantly lower tenacity in the aerosol was observed with a recovery rate of 4.24% for intermediate RH of approximately 50%. The results of this study confirm the significant influence of the RH on the tenacity of airborne microorganisms depending on the specific agent. These data show that the behavior of microorganism in bioaerosols is varies under different environmental conditions.
Weniger anzeigenDo different medico-scientific understandings of autoimmune inflammation, whose carriers disobediently promote the therapeutic use of immunostimulants, have the potential to destabilize the hegemony of the standard palliative treatment based on immunosuppression? Here I explore whether and how medical paradigms in Brazil develop and expand around immunopathologies through practices of exclusion and inclusion in the context of global circulation of knowledges, therapies, and regulatory frameworks. While focusing on concurrent immunotherapeutic models within biomedicine, I discuss aspects of legal-epistemological frictions that animate controversies in which distinct ways of co-producing medical evidence affect and are affected by the biomedical establishment.
Weniger anzeigenCaryophyllaceae with a cushion-like life form occur with a large number of species at the higher altitudes of the Andes (3500–5000 m) and have evolved convergently in several different lineages. Based on molecular phylogenetic analysis it is shown that members of the former genera Plettkea and Pycnophyllopsis, but also certain species previously classified as Arenaria constitute a subclade nested within the monophyletic genus Stellaria. Both plastid (trnK-matK-psbA + trnL-F) and nuclear (nrITS) trees converged on such a highly supported ‘Plettkea’ clade. Morphologically, the members of the ‘Plettkea’ subclade of Stellaria are further characterized by reduced to completely absent petals and seeds with a more or less conspicuous tuberculate testa. This clade is described as S. sect. Plettkea (Mattf.) Montesinos & Borsch. Species-level relationships within S. sect. Plettkea are also congruently inferred by plastid and nuclear genomic compartments, with three further sublineages recognized: Altogether, our detailed taxonomic revision showed that the ‘Plettkea’ clade in fact constitutes an Andean radiation of 21 species within Stellaria, four of which are described as new to science. Earlier treatments indicated just a few species with a putative placement. The results of this investigation underscore the importance of fieldwork and integrated molecular-morphological approaches to assess the species diversity in Andean plant groups. In addition to the phylogenetic analysis, we provide a taxonomic backbone including all names and types, descriptions and information on distribution and ecology and a key for identification. Regarding the next relatives of the S. sect. Plettkea clade, our plastid trees depict the ‘Nitentes’ clade of Stellaria as sister, whereas nrITS instead suggests a sister group relationship of the ‘Nitentes’ with the speciose ‘Larbreae’ clade. Our inferred relationships of major clades further deviate from published molecular trees by indicating an early branching position of the ‘Petiolares’ clade.
Weniger anzeigenCanine babesiosis has been increasingly diagnosed in various regions of Germany such as north-eastern Germany in recent years. A dog with several relapses of Babesia canis infection after treatment with imidocarb is described. A 9-year-old male Magyar Viszla with B. canis infection was referred after two treatments with imidocarb (dosage 2.1 mg/kg SC) because of lethargy, fever and pancytopenia (additional treatments with prednisolone and doxycycline). Merozoites were detected in the blood smear and imidocarb treatment was repeated. Clinical signs, pancytopenia and a positive B. canis PCR occurred after the 3rd (6 mg/kg SC), 4th (7.7 mg/kg SC) and 5th (7.5 mg/kg SC and doxycycline for 4 weeks in addition) imidocarb injection and thorough tick prevention with isoxazoline and permethrin products. 12 days after the 5th injection, the PCR was negative for the first time. The dog was again presented with fever 35 days after the 5th injection. The B. canis PCR was positive and laboratory examination revealed pancytopenia. Treatment with atovaquone/azithromycin for 18 days was performed and no further relapse occurred for 32 weeks. In the case of suspected imidocarb resistance in B. canis infection, treatment with atovaquone/azithromycin can be an alternative.
Weniger anzeigenPrecise synaptic connectivity is a prerequisite for the function of neural circuits, yet individual neurons, taken out of their developmental context, readily form unspecific synapses. How does the genome encode brain wiring in light of this apparent contradiction? Synaptic specificity is the outcome of a long series of developmental processes and mechanisms before, during and after synapse formation. How much promiscuity is permissible or necessary at the moment of synaptic partner choice depends on the extent to which prior development restricts available partners or subsequent development corrects initially made synapses. Synaptic promiscuity at the moment of choice can thereby play important roles in the development of precise connectivity, but also facilitate developmental flexibility and robustness. In this review, we assess the experimental evidence for the prevalence and roles of promiscuous synapse formation during brain development. Many well-established experimental approaches are based on developmental genetic perturbation and an assessment of synaptic connectivity only in the adult; this can make it difficult to pinpoint when a given defect or mechanism occurred. In many cases, such studies reveal mechanisms that restrict partner availability already prior to synapse formation. Subsequently, at the moment of choice, factors including synaptic competency, interaction dynamics and molecular recognition further restrict synaptic partners. The discussion of the development of synaptic specificity through the lens of synaptic promiscuity suggests an algorithmic process based on neurons capable of promiscuous synapse formation that are continuously prevented from making the wrong choices, with no single mechanism or developmental time point sufficient to explain the outcome.
Weniger anzeigenLa metáfora del teatro no sólo aparece en el título del Teatro crítico universal (1726–1739) de Benito Jerónimo Feijoo, sino también fue aducida por Pierre Bayle en su Projet et fragmens d’un dictionaire critique (1692). Es cierto que, a principios de la Edad Moderna, la metáfora del teatro podía emplearse y se empleaba en multitud de contextos y con fines muy diversos. Sin embargo, la combinación de teatro y error, tal y como se da tanto en Bayle como en Feijoo, merece un examen más detenido. Se muestra cómo el Theatrum vitae humanae (1565) de Theodor Zwinger, que es el texto en el que Bayle afirma basar su Dictionnaire, introduce una noción de teatro que no se centra en el escenario sino en el auditorio. Esto es significativo tanto para las estrategias de escritura de Bayle como para las de Feijoo, ya que apunta a la gestión de vastos cuerpos de conocimiento y, en última instancia, a la citacionalidad de ambos proyectos. Al mismo tiempo, sitúa al lector frente a la sabiduría tradicional y prepara así un espacio para el modo emergente de la crítica – por algunos caracterizado como escepticismo – que informa los proyectos de ambos autores.
Weniger anzeigenThe main purpose of this article is to describe and analyze Indigenous women’sparticipation in the prolonged takeover of Wounded Knee in 1973. Indigenouswomen’s grassroots activism was fundamental for sustaining and keeping the occu-pation alive, yet their contributions were largely eclipsed by the actions of theirmedia-savvy, male comrades-in-arms. What is more important, Indigenous women inthe American Indian Movement (AIM) frequently claimed that they were in a state of“double oppression” or “double colonization”—first, through colonial domination andracial inequality, and second, through male privilege and female subordination—itself,part of the legacy of colonization and the imposition of dominant white patriarchalmasculinity.2 Nationalist struggles such as that of the anticolonial AIM tend to repli-cate the very structures of male dominance that they struggle against. While womenhave been included in public discourse, they have been largely left out of politicaldecision-making.3
At Wounded Knee, Indigenous women took on a series of interrelated roles andresponsibilities that kept the occupation alive. Indigenous women skillfully renegoti-ated their gendered position of power within the masculinist organization, constructingfemininities that shifted between domesticated motherhood and female comrades-in-arms. In so doing, they both reaffirmed and challenged sexist and chauvinist attitudes within AIM. They were well known as long-standing community organizers, andtheir active participation at the Wounded Knee takeover was an indication of female empowerment.
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