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Effects of Forest Harvesting Operations on Hydrology: Experiences From the Palatinate Forest Biosphere Reserve
Full text linkThe use of timber harvesting and skidding machines significantly alters a catchment's hydrological processes due to soil compaction effects. Although it is obvious that the use of heavy forest machines increases surface runoff and water yield, quantifying these effects remains challenging. This research aimed at exploring how physically based hydrological models are suited for investigating the effects of soil compaction on hydrologic responses at the catchment scale. We employed a process-based SWAT+ hydrological model to assess the impact of temporary (e.g., skid trails) and more permanent timber harvest infrastructure on the hydrologic response of the Palatinate Forest Biosphere Reserve in Germany. We specifically analysed the role of soil compaction in hydrological processes by simulating water fluxes under three scenarios: uncompacted soil (baseline), compacted soil during harvest and skidding operations (Scenario-1) and due to permanently constructed infrastructures (Scenario-2). Results demonstrated substantial alterations in water fluxes under Scenarios-1 and -2 compared to the baseline, with annual average surface runoff increasing by 74% and 125%, respectively, and lateral flow decreasing by 14% and 26%. These changes varied notably between steep and low slope areas. Steep slope regions exhibited significantly larger increases in surface runoff, while low slope areas experienced greater reductions in lateral flow and percolation. This differentiation underlines the combined influence of management scenarios and slope, highlighting the critical need for forest harvesting strategies that account for spatial variability and the types of machinery employed
Evolution of sympatric host‐specialized lineages of the fungal plant pathogen Zymoseptoria passerinii in natural ecosystems
Full text linkThe barley disease Septoria Speckled Leaf Blotch, caused by the fungus Zymoseptoria passerinii, last appeared in North America in the early 2000s. Although rare in crops, field sampling of wild grasses in the Middle East revealed the disease persistence in wild barley. Identification of Z. passerinii in various wild barley species prompted us to examine genomic signatures of host specialization and trace the emergence of the domesticated-barley-infecting lineage. Furthermore, we applied virulence assays and confocal laser microscopy to evaluate whether the disease development differs between wild and domesticated barley. Wild- and domesticated-host-infecting populations have diverged, and phylogenetic relationships support the evolution of sympatric host-specialized lineages in wild hosts. Cross-virulence assays showed that Z. passerinii from domesticated hosts infect domesticated barley and its wild ancestor, Hordeum spontaneum. However, wild isolates from Iran did not infect domesticated barley. Wild and domesticated pathosystems have similar disease timing and progression, suggesting its persistence does not depend on a shorter period of incubation. The study supports that a wide range of hosts can foster the evolution of host-specialized lineages in sympatry and provide novel insights into the evolution of understudied fungal pathogens on wild hosts
Essays on Stock Market Reactions to Corporate Tax Reforms and Tax Avoidance
No full textThis cumulative dissertation examines stock market reactions to corporate tax reforms and tax avoidance. The first essay analyzes investor responses to a tax reform announcement in the United Kingdom that included a substantial corporation tax hike to consolidate the budget in the recovery phase after the COVID-19 pandemic. The results indicate that governments face tradeoffs in stabilizing the economy, as companies severely affected by preceding crises benefit from assured government support, while the tax rate hike penalizes more dynamic companies, thus jeopardizing future growth. However, in the presence of macro-financial risk due to excessive public debt, regaining fiscal stability becomes crucial from an investor’s perspective, even if it involves tax increases. The second essay provides a comprehensive review of the strongly growing strand of literature on the valuation of tax-related events by stock market investors. It traces the evidence from early insights on the value relevance of corporate taxes to key learnings about the relevance of tax drivers beyond the tax rate up to major tax events of the more recent past, which are centered around the stock price implications of tax avoidance, the restriction of tax planning leeway, fundamental reforms intended to ensure fairer taxation, and unilateral tax reforms aimed at increasing competitiveness or fiscal adjustment. The third essay investigates the stock market reaction to a German tax reform that was aimed at stimulating growth through tax relief and relied on targeted tax incentives. The results show that investors generally assess the tax relief provided positively, but do not expect it to be substantial enough to considerably improve the economic position of German firms. The stock market reaction to the final approval of the act further confirms that investors do not expect any strong growth impetus from the tax incentives introduced
Unlocking the Chemical and Structural Complexity of Aluminum Hydroxy Acetates: from Commodity Chemicals to Porous Materials
Full text linkAluminum acetates have been in use for more than a century, but despite their widespread commercial applications, essential scientific knowledge of their synthesis-structure-property relationships is lacking. High-throughput screening, followed by fine tuning and extensive optimization of reaction conditions using Al3+, OH- and CH3COO- ions, has unraveled their complex synthetic chemistry, yielding for the first time the four phase pure products Al(OH)(O2CCH3)2 ⋅ x H2O (x=0, 2) (1A and CAU-65, 1B), Al3O(HO2CCH3)(O2CCH3)7 (2), and the porous aluminum salt [Al24(OH)56(CH3COO)12](OH)4 (CAU-55-OH, 3). Structure determination by electron and X-ray diffraction was carried out and the data suggested porosity for 1B and 3, which was confirmed by physisorption experiments. Even the scale-up to the 10 L scale was accomplished for 1A, 1B and 3 with yields of up to 1.1 kg (99 %). This study of a seemingly simple chemical system provides important information on both fundamental inorganic chemistry and porous materials
Advancing Energy Materials by In Situ Atomic Scale Methods
Full text linkDespite significant advancements in materials design for renewable energy devices, the fundamental understanding of the underlying processes in many materials remains limited, particularly in complex, inhomogeneous systems and interfaces. In such cases, in situ studies with high spatial and energy resolution are essential for uncovering new insights into excitation, dissipation, and conversion processes. Recent progress in in situ atomic scale methods has greatly enhanced the understanding of energy materials. Here, key advances are reviewed, including in situ, environmental and ultra-fast transmission electron microscopy, scanning probe techniques, single-photon-resolved infrared spectroscopy, velocity-resolved molecular kinetics, and in situ grazing-incidence X-ray spectroscopy. These techniques enable the study of energy conversion with spatial resolution from nanometers down to individual atoms, energy resolution down to meV, and single-quantum detection. Especially they enable access to processes that involve multiple degrees of freedom, strong coupling, or spatial inhomogeneities. They have driven a qualitative leap in the fundamental understanding of energy conversion processes, opening new avenues for improving existing materials and designing novel clean and efficient energy materials in photovoltaics, friction, and surface chemistry and (photo-)electrochemistry
Travertine increases the concentration of trace elements in groundwater in Chahar Takab, Fariman county, northeast Iran
Full text linkGroundwater has emerged as a crucial water source, supplying half of the world’s domestic water needs, particularly in rural areas without supply systems. This study assesses the impact of travertine formations, on water quality in Chahar Takab village, Iran, focusing on suitability for human consumption and ecosystem sustainability where groundwater is the primary source. Thirty-four samples from various sources, including travertine springs, surface water, and groundwater, underwent ICP-OES analysis. Travertine springs exhibited higher electrical conductivity (EC), lower pH, and elevated concentrations of major cations (Na, Ca, Mg) and anions (Cl, HCO3). In them, all samples exceeded European Union limits for Cl and Na in drinking water. Hydrochemical facies were influenced by water-rock interactions, leading to Ca-HCO3 dominance in surface and groundwater samples and Ca-Mg-Cl dominance in travertine springs. Heavy metal analysis revealed high concentrations of As, B, Fe, Mn, and Pb in travertine spring and surface water samples, with As exceeding World Health Organization limits by up to 28.5 times. Additionally, the Metal Index indicated values exceeding drinking water guidelines set by the World Health Organization in 58% of the samples. Travertine springs had the highest toxicity risks, especially for As, Cd, and Pb. Results suggest a tectonic origin for heavy metal contamination (As-containing travertine springs), emphasizing the need for mitigation measures and regular monitoring. Action is necessary to address water quality issues in the region
Factors associated with reduction in quality of life after SARS-CoV-2 infection
Full text linkLong-term changes in health-related quality of life (HrQoL) after SARS-CoV-2 infection are common, but their causes and consequences are poorly understood. This prospective, population-based study examined associations between HrQoL and 49 demographic and clinical variables. HrQoL was assessed using the European Quality-of-Life-5-Dimensions-5-Level-Version in 3,475 participants (56% female; aged 18-88 years) approximately 9 months (baseline) and 26 months (follow-up) after their initial infection. Results were compared with the demographic and clinical variables using recursive feature elimination and random forest regression analyses. A statistically significant improvement in HrQoL was observed during the observation period. At baseline, 39% of the variance in HrQoL was explained by fatigue, muscle pain, number of remaining symptoms (RS), perceived stress, and age. At follow-up, fatigue, RS, perceived stress, muscle and joint pain, and age explained 54% of the variance in HrQoL. Changes in HrQoL were associated with changes in fatigue, RS, and perceived stress, meaning that if these decreased from baseline to follow-up, then HrQoL was improved. However, it was not possible to predict whether an individual's HrQoL would improve or worsen 1 year later based on baseline variable scores. The aforementioned symptoms are specifically associated with impairment in the population's usual activities
HYTANE-Identified Latrophilin-3 Cleavage by Meprin β Leads to Loss of the Interaction Domains
Full text linkThe metalloprotease meprin β is upregulated in neurons and astrocytes of Alzheimer's disease patients' brains. While the role of meprin β as the β-secretase of amyloid precursor protein (APP) has been characterized, its broader substrate profile within the brain remains largely unexplored. Hence, to identify additional substrates, we conducted N-terminomics of brain lysates from mice overexpressing meprin β in astrocytes employing the Hydrophobic Tagging-Assisted N-terminal Enrichment (HYTANE) strategy. We observed 3906 (82.2%) N-terminal peptides and identified seven new substrates that match meprin β in terms of localization and cleavage specificity. Of note, the meprin β overexpressing mice show mild cognitive impairments caused by amyloidogenic APP processing alongside hyperactivity and altered exploratory behavior seemingly independent of APP cleavage. Hence, latrophilin-3 was of particular interest, as latrophilin-3 defects are associated with hyperactivity in mice and human. In brain lysates from mice overexpressing meprin β in astrocytes as well as in cellulo, we validated the cleavage of latrophilin-3, resulting in the release of two N-terminal domains. These domains promote interactions with neuronal proteins such as fibronectin leucine-rich repeat transmembrane proteins, promoting adequate synapse formation. Thus, meprin β might affect synaptic integrity by cleaving interaction domains of latrophilin-3, potentially exacerbating the observed hyperactivity phenotype
Trabecular texture and paraspinal muscle characteristics for prediction of first vertebral fracture: a QCT analysis from the AGES cohort
Full text linkVertebral fractures (VFs) significantly increase risk of subsequent fractures. Areal bone mineral density (BMD) assessed by DXA and volumetric BMD by QCT, are strong predictors of VF. Nevertheless, risk prediction should be further improved. This study used data from the Age, Gene/Environment Susceptibility Reykjavik (AGES-Reykjavik) cohort to evaluate whether trabecular texture and paraspinal muscle assessments improve the prediction of the first incident VF. CT scans of the L1 and L2 vertebrae of 843 elderly subjects; including 167 subjects with incident, VFs occurring within a 5-year period and 676 controls without fractures. Image analysis included measurement of BMD, cortical thickness and of parameters characterizing trabecular architecture and the autochthonous muscles. Fifty variables were used as predictors, including a BMD, a trabecular texture and a muscle subset. Each included age, BMI and corresponding parameters of the QCT analysis. The number of variables in each subset was reduced using stepwise logistic regression to create multivariable fracture prediction models. Model accuracy was assessed using the likelihood ratio test (LRT) and the area under the curve (AUC) criteria. Bootstrap analyses were performed to assess the stability of the model selection process. 96 women and 78 men with prior VF were excluded. Of 50 initial predictors, 17 were significant for women and 11 for men. Bone and texture models showed significantly better fracture prediction in women (p<0.001) and men (p<0.01) than the combination of age and BMI. The muscle model showed better fracture prediction in men only (p<0.03). Compared to the BMD model alone, LRT showed a significantly improved VF prediction of the combinations of BMD with texture (women and men) (p<0.05) [...
Impact of Soil Amendments and Alternate Wetting and Drying Irrigation on Growth, Physiology, and Yield of Deeper-Rooted Rice Cultivar Under Internet of Things-Based Soil Moisture Monitoring
Full text linkEffective water and soil management is crucial for crop productivity, particularly in rice cultivation, where poor soil quality and water scarcity pose challenges. The response of deeper-rooted rice grown in soils amended with different soil amendments (SAs) to Internet of Things (IoT)-managed alternate wetting and drying (AWD) irrigations remains undetermined. This study explores the effects of various SAs on DRO-1 IR64 rice plants under IoT-based soil moisture monitoring of AWD irrigation. A greenhouse experiment executed at the Tokyo University of Agriculture assessed two water management regimes—continuous flooding (CF) and AWD—alongside six types of SAs: vermicompost and peat moss (S + VC + PM), spirulina powder (S + SPP), gypsum (S + GS), rice husk biochar (S + RHB), zeolite (S + ZL), and soil without amendment (S + WA). Soil water content was continuously monitored at 10 cm depth using TEROS 10 probes, with data logged via a ZL6 device and managed through the ZENTRA Cloud application (METER GROUP Company). Under AWD conditions, VC + PM showed the greatest decline in volumetric water content due to enhanced root development and water uptake. In contrast, SPP and ZL maintained consistent water levels. Organic amendments like VC + PM improved soil properties and grain yield, while AWD with ZL and GS optimized water use. Strong associations exist between root traits, biomass, and grain yield. These findings highlight the benefits of integrating SAs for improved productivity in drought-prone rice systems