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Parametric modeling framework for assessing urban structure vulnerability to natural disasters
No full textEin Konsensus der Deutschsprachigen Arbeitsgemeinschaft für Mikrochirurgie (DAM): Welche apparative Diagnostik ist für die Darstellung der Anschlussgefäße vor mikrochirurgischen Transplantationen an der unteren Extremität notwendig?
No full textLinear free energy relationship between reduction potential and photoreduction rate: studies on Drosophila cryptochrome
No full textCryptochromes are flavin adenine dinucleotide (FAD)-containing blue-light photoreceptors involved in the regulation of the circadian clock and may play a role in magnetic field sensing. The photochemistry of cryptochromes is based on the isoalloxazine moiety, which can be photoreduced and subsequently reoxidized by an electron acceptor such as oxygen, corresponding to a photo-switch between the dark and signaling state. We replaced the FAD cofactor of Drosophila cryptochrome with a series of FAD cofactors modified at the 7α or 8α positions, in order to modulate the chemical properties of the electron acceptor. These modifications were shown to alter the kinetics of the light-dependent reactions. Notably, 7-halogenated FADs form the signaling state more than six times faster compared to the natural FAD cofactor. The more positive reduction potentials as well as the increased intersystem crossing rates due to heavy halogen atoms were identified as reasons for the altered photochemistry. Both parameters show a linear dependence on the reaction kinetics, according to the Hammett relationship. With this knowledge, the photochemistry of cryptochromes may be modified in a defined way without changing its amino acid sequence
An early-life survival and reproductive trade-off shapes selection on body size
No full textEvolutionary trade-offs—opposing trait effects on total fitness via different fitness components—are likely to be widespread. Some key trade-offs are expected to be the result of chains of causation acting across an organism’s lifetime. For example, a trait imparting reproductive benefits early in life may trade off against reduced survival to attain later-life reproductive opportunities. Tools in evolutionary quantitative genetics have recently been developed to formally characterize selection acting through different causal pathways throughout the life cycle and, therefore, to formally characterize evolutionary trade-offs. We use these methods to investigate a trade-off between early life reproduction and survival and how that trade-off affects selection on body size in the Soay sheep population inhabiting St Kilda (Outer Hebrides, Scotland). We decompose and quantify the total effects of first-year female body mass on lifetime fitness, with particular attention to the effect of body mass on early-life reproduction and the potential survival cost of early-life reproduction. Our results establish that the total effect of body mass on lifetime fitness is positive, despite the strong negative contribution acting via early life reproduction. Moreover, we show that the magnitude of the selection on body mass acting through different causal paths highly depends on population density. At higher densities, the cost of early-life reproduction is higher, and therefore, it contributes a strong negative component to the total selection of body mass—i.e., at higher population density, selection on body mass is weaker than it is when the population density is smaller. By decomposing total selection and quantifying selection acting through different causal paths, we expose the underlying mechanics shaping body mass in Soay sheep female lambs, and we provide a meaningful contribution to the understanding of the evolution of body size in this population
The relationship between therapeutic alliance, early symptom change, and outcome among in-patients with anorexia nervosa
No full textObjectiveTherapeutic alliance (TA) is an important process variable, evidence suggesting its influence on treatment outcome across several mental disorders. Yet, its role in treating anorexia nervosa (AN) remains under-examined. Previous research has yielded heterogeneous results, indicating a complex relationship between TA, early change, and outcome, potentially depending on contributing factors like age. This relationship was examined in a sample of 173 adult and adolescent inpatients with AN treated in a specialized clinic.MethodData were collected in weeks 2, 5, 9, and the week before discharge. Outcome was defined dimensionally (Eating Disorder Examination Questionnaire, Body Mass Index) and categorically (premature termination, weight status, remission status). Several potential influencing factors (e.g., duration of illness, previous therapy) were analyzed. The effect of TA on early change and outcome, and vice versa, was analyzed using regression analyses.ResultsTA was positively associated with greater early weight gain and overall general symptom change. Later TA predicted premature termination and remission status. The latter effect ceased when early change was considered. The TA subscale “task” played the most important role. Early change in ED symptoms predicted better TA later in treatment.DiscussionIn accordance with previous research, a complex bidirectional relationship between TA and outcome in AN patients was identified. The results indicate the importance of focusing on symptom improvement as well as establishing an agreement on therapeutic tasks. Future research should concentrate on the complexity and bidirectionality of TA and symptom change over the course of treatment, considering possible mediators
cGAS-STING are responsible for premature aging of telomerase-deficient zebrafish
No full textTelomere shortening occurs in multiple tissues throughout aging. When telomeres become critically short, they trigger DNA-damage responses and p53 stabilization, leading to apoptosis or replicative senescence. In vitro, cells with short telomeres activate the cGAS-STING innate immune pathway resulting in type-I interferon-based inflammation and senescence. However, the consequences of these events for the organism are not yet understood. Here, we show that sting is responsible for premature aging of telomerase-deficient zebrafish. We generated sting-/- tert-/- double-mutant animals and observed a thorough rescue of tert-/- phenotypes. At the cellular level, lack of cGAS-STING in tert mutants resulted in reduced senescence, increased cell proliferation, and decreased inflammation despite similarly short telomeres. Critically, absence of sting function resulted in dampening of the DNA damage response and reduced p53 levels. At the organism level, sting-/- tert-/- zebrafish regained fertility, showed delayed cachexia, and decreased cancer incidence, resulting in increased healthspan and lifespan of telomerase mutant animals
Disruptive geographies and the war on Gaza : infrastructure and global solidarity
No full textThis forum explores the geopolitics of infrastructure in the context of Israel’s war on Gaza, situating the current genocide within longer histories of settler colonialism, spatial control, and transnational complicity. As homes, hospitals, and schools are reduced to rubble, this destruction is not only military, but infrastructural – an assault on the material conditions of Palestinian life. Infrastructure emerges here not as background, but as a primary mechanism of governance, dispossession, and colonial reordering. From roads and borders to electricity grids and telecommunications, the systems that organise everyday life in Gaza and the West Bank are also those that fragment space, enforce dependency, and suppress self-determination. Rather than viewing this destruction in isolation, contributors trace how it is sustained by regional and global circuits of capital, logistics, arms, and energy. Gaza’s collapse is embedded in a broader political economy of militarism, where supply chains, defence industries, and financial infrastructures turn dispossession into profit. Yet, this forum also foregrounds counter-infrastructures and practices of resistance: from survival networks and subterranean spaces of refusal, to workers’ strikes and transport disruptions that challenge the flows sustaining Israeli militarism. Together, these essays ask what it means to ‘follow infrastructures’ in a moment of mass atrocity – what such a method reveals about power, complicity, and potential rupture. The forum moves beyond documenting destruction to consider how infrastructure is both a tool of domination and a terrain of struggle. Across scales and contexts, it highlights how Palestinians resist infrastructural warfare and how international solidarity movements can intervene in the systems that enable it. In doing so, the forum contributes to a growing body of politically accountable scholarship, mapping not only how infrastructures sustain violence, but how they might be reimagined
Evergreen citrus trees exhibit distinct seasonal nitrogen remobilization patterns between mature leaves and bark
No full textSeasonal nitrogen (N) storage and remobilization are critical for tree growth. Deciduous trees primarily store N in bark; evergreen trees utilize both mature leaves and bark. Citrus is an evergreen species; leaf N storage and remobilization are well studied, but inner bark remains poorly understood. This study used pot experiments with N supply rates (low, moderate and high) to examine seasonal (winter, early, and late spring) N storage and remobilization between mature leaves (developed in autumn) and bark (main stem). Bark contains 15–35 kDa of vegetative storage proteins (VSPs), which are highly abundant and accumulate seasonally, while mature leaves contain 45–55 kDa of VSPs. Proteomic analysis revealed the oxygen-evolving enhancer protein as a key bark VSP, with Rubisco and others predominant in leaves. Under high N supply, the reduction ratio of total N content in bark from winter to early spring was higher than that in mature leaves. Under high N supply, bark arginine decreased significantly in early spring, whereas mature leaf arginine remained unchanged. Under low N supply, the decrease in proline content from winter to late spring was significantly greater in mature leaves than in bark. Thus, under high N, bark supply more arginine in early spring, whereas under low N, leaves supply more proline later. Bioinformatics indicate that ribosomal proteins may be involved in N remobilization in bark under high N and in both bark and leaves under low N. These results demonstrate that bark and mature leaves exhibit different seasonal N remobilization patterns
Invasion timing affects multiple scales, metrics, and facets of biodiversity outcomes in ecological restoration experiments
No full textThe need to develop optimal restoration protocols for degraded grasslands has led to experimental research aimed at determining how different restoration treatments influence outcomes for biodiversity. The magnitude and direction of diversity responses to restoration treatments may depend on the spatial scale at which diversity is measured (local, regional), the metric of diversity used (Hill numbers), and the facet of diversity (taxonomic, functional, phylogenetic) considered. We conducted a long-term factorial experiment in a degraded grassland in Missouri, USA, in which we experimentally applied a regionally appropriate biodiverse seed mixture, added soil nutrients to restore soil fertility, and varied the timing in which the invasive plant Lespedeza cuneata entered the community. We used a unified framework of Hill numbers to evaluate how treatments influenced diversity, considering different spatial scales, metrics, and facets (taxonomic, phylogenetic, functional). We find that the timing in which the invasive L. cuneata entered the community had large effects on diversity, while nutrient addition had more limited effects. This was driven by the high dominance of the focal invasive when allowed to invade early in the growing season, suppressing diversity. The positive effects of late invasion increased in magnitude with spatial grain and were higher for taxonomic than phylogenetic and functional facets of diversity. This was largely due to the dominance of the focal invasive, negatively affecting diversity within specific plant families or functional phenotypes across treatments. Under early invasion, nutrients had a negative effect, particularly at local scales, inflating beta diversity in this treatment and resulting in negative to no effect of late invasion on many aspects of beta diversity. Our results demonstrate the importance of looking at a multitude of different measures of diversity to understand the relative effects of ecological restoration treatments combined with invasion timing. Efforts to keep noxious plant invaders out of a system early in restoration approaches better allow desirable, native plants to establish and can have long-term benefits for multiple aspects of diversity