Hasil untuk "History of Germany"

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DOAJ Open Access 2025
Rotational Spectroscopy and Tentative Interstellar Detection of 3-hydroxypropanal (HOCH2CH2CHO) in the G+0.693-0.027 Molecular Cloud

Zachary T. P. Fried, Roman A. Motiyenko, Miguel Sanz-Novo et al.

We synthesized the astrochemically relevant molecule 3-hydroxypropanal (HOCH _2 CH _2 CHO) and subsequently measured and analyzed its rotational spectrum in several frequency regions ranging from 130 to 485 GHz. We analyzed the ground vibrational state as well as the two perturbed lowest-lying vibrationally excited states. With the resulting rotational parameters, we searched for this molecule in the Sagittarius B2(N) and NGC 6334I hot cores, the IRAS 16293-2422B hot corino, and the G+0.693-0.027 and TMC-1 molecular clouds. Rotational emission of 3-hydroxypropanal was tentatively detected toward G+0.693-0.027, and a column density of (8.6 ±1.4) × 10 ^12 cm ^−2 was determined. However, this molecule was not detected in the other sources that were investigated. The chemical implications of this tentative discovery are analyzed, and several potential chemical formation pathways of this species are discussed.

arXiv Open Access 2024
An essay on the history of DSGE models

Genaro Martín Damiani

Dynamic Stochastic General Equilibrium (DSGE) models are nowadays a crucial quantitative tool for policy-makers. However, they did not emerge spontaneously. They are built upon previously established ideas in Economics and relatively recent advancements in Mathematics. This essay provides a comprehensive coverage of their history, starting from the pioneering Neoclassical general equilibrium theories and eventually reaching the New Neoclassical Synthesis (NNS). In addition, the mathematical tools involved in formulating a DSGE model are thoroughly presented. I argue that this history has a mixed nature rather than an absolutist or relativist one, that the NNS may have emerged due to the complementary nature of New Classical and New Keynesian theories, and that the recent adoption and development of DSGE models by central banks from different countries has entailed a departure from the goal of building a universally valid theory that Economics has always had. The latter means that DSGE modeling has landed not without loss of generality.

en econ.GN
arXiv Open Access 2024
HZ_evolution: A Package to Calculate Habitable Histories

Noah W. Tuchow, Jason T. Wright

We present HZ_evolution, a Python package to characterize the habitable histories of exoplanets. Given inputs of a planet's current effective flux and host star properties, HZ_evolution calculates its instellation history, the evolution of the star's Habitable Zone, and the duration the planet spends inside or outside the Habitable Zone.

en astro-ph.EP, astro-ph.IM
arXiv Open Access 2024
Personalised Outfit Recommendation via History-aware Transformers

Myong Chol Jung, Julien Monteil, Philip Schulz et al.

We present the history-aware transformer (HAT), a transformer-based model that uses shoppers' purchase history to personalise outfit predictions. The aim of this work is to recommend outfits that are internally coherent while matching an individual shopper's style and taste. To achieve this, we stack two transformer models, one that produces outfit representations and another one that processes the history of purchased outfits for a given shopper. We use these models to score an outfit's compatibility in the context of a shopper's preferences as inferred from their previous purchases. During training, the model learns to discriminate between purchased and random outfits using 3 losses: the focal loss for outfit compatibility typically used in the literature, a contrastive loss to bring closer learned outfit embeddings from a shopper's history, and an adaptive margin loss to facilitate learning from weak negatives. Together, these losses enable the model to make personalised recommendations based on a shopper's purchase history. Our experiments on the IQON3000 and Polyvore datasets show that HAT outperforms strong baselines on the outfit Compatibility Prediction (CP) and the Fill In The Blank (FITB) tasks. The model improves AUC for the CP hard task by 15.7% (IQON3000) and 19.4% (Polyvore) compared to previous SOTA results. It further improves accuracy on the FITB hard task by 6.5% and 9.7%, respectively. We provide ablation studies on the personalisation, constrastive loss, and adaptive margin loss that highlight the importance of these modelling choices.

en eess.SY, cs.IT
DOAJ Open Access 2024
Long-term seizure outcome after epilepsy surgery of neuroglial tumors

Attila Rácz, Philipp Müller, Albert Becker et al.

PurposeNeuroglial tumors are frequently associated with pharmacorefractory epilepsies. However, comprehensive knowledge about long-term outcomes after epilepsy surgery and the main prognostic factors for outcome is still limited. We sought to evaluate long-term outcomes and potential influencing factors in a large cohort of patients who underwent surgery for neuroglial tumors in a single-center setting.MethodsThe study analyzed the outcomes of 107 patients who underwent epilepsy surgery for neuroglial tumors between 2001 and 2020 at the Department of Epileptology, University Hospital Bonn, in Germany. The outcomes were evaluated using Engel classification. Differences in outcome related to potential prognostic factors were examined using the Chi2-test, Fisher’s exact test and sign test. Additionally, stepwise logistic regression analysis was employed to identify independent prognostic factors.ResultsComplete seizure freedom (Engel Class IA) was achieved in 75% of the operated patients at 12 months, and 56% at the last follow-up visit (70.4 ± 6.2 months, median: 40 months). Completeness of resection was a crucial factor for both 12-month follow-up outcomes and the longest available outcomes, whereas lobar tumor localization, histology (ganglioglioma vs. dysembryoplastic neuroepithelial tumor), history of bilateral tonic–clonic seizures prior to surgery, invasive diagnostics, side of surgery (dominant vs. non-dominant hemisphere), age at epilepsy onset, age at surgery, and epilepsy duration did not consistently impact postsurgical outcomes. Among temporal lobe surgeries, patients who underwent lesionectomy and lesionectomy, including hippocampal resection, demonstrated similar outcomes.ConclusionNeuroglial tumors present as excellent surgical substrates in treating structural epilepsy. To achieve an optimal postsurgical outcome, a complete lesion resection should be pursued whenever possible.

Neurology. Diseases of the nervous system
DOAJ Open Access 2024
Identification of the Top TESS Objects of Interest for Atmospheric Characterization of Transiting Exoplanets with JWST

Benjamin J. Hord, Eliza M.-R. Kempton, Thomas M. Evans-Soma et al.

JWST has ushered in an era of unprecedented ability to characterize exoplanetary atmospheres. While there are over 5000 confirmed planets, more than 4000 Transiting Exoplanet Survey Satellite (TESS) planet candidates are still unconfirmed and many of the best planets for atmospheric characterization may remain to be identified. We present a sample of TESS planets and planet candidates that we identify as “best-in-class” for transmission and emission spectroscopy with JWST. These targets are sorted into bins across equilibrium temperature T _eq and planetary radius R _p and are ranked by a transmission and an emission spectroscopy metric (TSM and ESM, respectively) within each bin. We perform cuts for expected signal size and stellar brightness to remove suboptimal targets for JWST. Of the 194 targets in the resulting sample, 103 are unconfirmed TESS planet candidates, also known as TESS Objects of Interest (TOIs). We perform vetting and statistical validation analyses on these 103 targets to determine which are likely planets and which are likely false positives, incorporating ground-based follow-up from the TESS Follow-up Observation Program to aid the vetting and validation process. We statistically validate 18 TOIs, marginally validate 31 TOIs to varying levels of confidence, deem 29 TOIs likely false positives, and leave the dispositions for four TOIs as inconclusive. Twenty-one of the 103 TOIs were confirmed independently over the course of our analysis. We intend for this work to serve as a community resource and motivate formal confirmation and mass measurements of each validated planet. We encourage more detailed analysis of individual targets by the community.

DOAJ Open Access 2024
Fenye by the Numbers: A Quantitative Analysis of Astrological Contents in Chinese Local Gazetteers

Chen Shih-Pei

Fenye (分野, lit., “field allocation”), is a traditional Chinese astrological system that associated celestial phenomena with regions on earth since ancient times. During middle and late imperial China, many literati writings criticized this system as illogical. Yet in the local gazetteers that were compiled in late imperial China to document local data within each administrative region, compilers continued to use fenye as the canonical way to identify their regions within the vast empire. The Jesuit introduction of Western sciences to China, in particular the technology that could precisely locate any place or region with latitude and longitude, appeared to render fenye obsolete, which fueled even more literati criticism. Modern scholars consider the public criticism from the Qianlong emperor and the resulting removal of fenye from the 1781 Rehe Gazetteer the end of fenye in imperial orthodoxy. However, by quantitatively analyzing a collection of 4,410 titles of local gazetteers and their section headings, this paper reveals many examples of local literati who resisted removing fenye entirely from their local history, well into the late Republican period.

History (General)
DOAJ Open Access 2024
Exploring botanical diversity, ecological traits, and edaphic determinants in Kala Chitta National Park, Pakistan: Implications for conservation and management

Muhammad Waheed, Um e Hani, Fahim Arshad et al.

Globally, environmental degradation has prompted several countries to strengthen their protected area networks to halt biodiversity loss. National parks incorporate into their design, are based on scientific evidence, and offer a complete management mechanism to enable successful conservation for the most ecologically critical and vulnerable ecosystem. However, managing these protected areas effectively requires a grasp of the complex dynamics of plant ecosystems and edaphic factors. Nevertheless, Pakistan's protected areas have seen the least investigation of these relationships. To fill this knowledge gap, this study investigates the vegetation dynamics and edaphic factors that influence plant distribution in Kala Chitta National Park of Pakistan. A comprehensive botanical survey documented 203 plant species across 60 study sites, revealing a diverse flora comprising species from 160 genera and 54 families. The most abundant families were Poaceae (34 species) and Fabaceae (21 species), Amaranthaceae (13 species) and Asteraceae (15 species). The majority of species were herbaceous (49.2%), followed by grasses (16.7%) and shrubs (15.2%). Climbers and ferns constituted 1.4% and 1.9% of the total, respectively, with co-dominant habits of tall reed and sedge accounting for 2.9% of the vegetation. Ecologically, Therophytes emerged as the most numerous life forms (42.8%), followed by hemicryptophytes (17.7%) and megaphanerophytes (8.3%). Analysis of leaf spectra revealed Nanophylls as the dominant type (36.9%), followed by Microphylls (33%). Phytogeographical distribution highlighted three major clusters, with Asia Tropical, Asia Temperate, and Europe accounting for 45% of species. Four distinct plant communities were identified using TWINSPAN analysis: Senegalia-Dichanthium-Justica (SDJ), Neltuma-Lantana-Cannabis (NLC), Prosopis-Saccharum-Desmostachya (PSD), and Dodonaea-Alhagi-Oxalis (DAO). Each community exhibited unique species compositions and ecological gradients influenced by edaphic factors. PCA revealed associations between specific edaphic variables and plant communities, with available phosphorus (AP) and potassium (AK) linked to the NLC community. At the same time, total nitrogen (TN) was predominantly associated with the DAO community. These findings highlight the importance of soil conservation and sustainable land management practices for preserving biodiversity and ecosystem integrity within Kala Chitta National Park. Future research should focus on long-term monitoring of vegetation dynamics and collaborative conservation initiatives involving local stakeholders to promote ecosystem resilience in the face of environmental change.

Environmental sciences
DOAJ Open Access 2024
The energy–population dividend: evidence from energy-specific population projections

Camille Belmin, Peter-Paul Pichler, Guillaume Marois et al.

In a climate-constrained world, understanding the energy required to achieve universal access to modern energy is critical. This requires making assumptions on future population trajectories. Although access to modern energy can affect population dynamics, this feedback has not yet been accounted for in demographic models. Access to modern energy leads to fertility declines as it reduces child mortality, improves health, increases women’s access to information, education and employment. In this paper we present a demographic model that endogenizes the effect of increased access to modern energy on population dynamics and estimates the size of this effect on total final energy use by households for the case of Zambia. To do so, we built a microsimulation model to project future population size and composition, accounting for how fertility depends on access to modern energy and education. We used these population projections to then estimate household energy demand of the Zambian population until 2070, under different scenarios. We found that in 2070, while electricity consumption is higher in a universal access scenario compared to a baseline scenario, total energy demand is 29% lower, partly due to a strong decline in the use of inefficient traditional cooking fuels. We also found that reduced population growth due to universal energy access contributes to lowering the energy demand by 56% by 2050, compared to a more limited expansion in energy access, and this contribution increases over time. Although the challenge of achieving universal access to modern energy seems daunting, our results suggest that this could have co-benefits with achieving climate goals. Our study also reveals that accounting for the energy–population dividend in energy models will scale down the currently assumed energy needs to ensure a decent life for all.

Environmental technology. Sanitary engineering, Environmental sciences
DOAJ Open Access 2024
Search for the decay of the Higgs boson to a Z boson and a light pseudoscalar particle decaying to two photons

G. Aad, B. Abbott, K. Abeling et al.

A search for the decay of the Higgs boson to a Z boson and a light, pseudoscalar particle, a, decaying respectively to two leptons and to two photons is reported. The search uses the full LHC Run 2 proton–proton collision data at s=13 TeV, corresponding to 139 fb−1 collected by the ATLAS detector. This is one of the first searches for this specific decay mode of the Higgs boson, and it probes unexplored parameter space in models with axion-like particles (ALPs) and extended scalar sectors. The mass of the a particle is assumed to be in the range 0.1–33 GeV. The data are analysed in two categories: a merged category where the photons from the a decay are reconstructed in the ATLAS calorimeter as a single cluster, and a resolved category in which two separate photons are detected. The main background processes are from Standard Model Z boson production in association with photons or jets. The data are in agreement with the background predictions, and upper limits on the branching ratio of the Higgs boson decay to Za times the branching ratio a→γγ are derived at the 95% confidence level and they range from 0.08% to 2% depending on the mass of the a particle. The results are also interpreted in the context of ALP models.

DOAJ Open Access 2024
Safeguarding Our Heritage—The TRIQUETRA Project Approach

Charalabos Ioannidis, Styliani Verykokou, Sofia Soile et al.

Cultural heritage (CH) sites are frequently exposed to natural elements, and their exposure becomes particularly precarious with the onset of climate change. This increased vulnerability places these sites at risk of deterioration or complete destruction. Risks such as land deformation, floods, acid rain, and erosion significantly threaten historic monuments, while water-related hazards, significantly influenced by both climate change and human activities, present a particularly grave risk to these invaluable sites. Considerable research efforts have focused on safeguarding CH sites. However, there remains a deficiency in systemic approaches towards identifying and mitigating risks for CH sites. The TRIQUETRA project proposes a technological toolbox and a methodological framework for tackling climate change risks and natural hazards threatening CH in the most efficient way possible. It aims at creating an evidence-based assessment platform allowing precise risk stratification as well as a database of available mitigation measures and strategies, acting as a Decision Support System (DSS) towards efficient risk mitigation and site remediation. TRIQUETRA is a European project that brings together a diverse group of researchers with varied expertise, encompassing university research groups, research institutes, public entities, as well as small and medium-sized enterprises. In this article, TRIQUETRAs overall methodology is presented, and preliminary results concerning risk identification, TRIQUETRAs knowledge base, as well as novel sensors and coatings, are discussed.

arXiv Open Access 2023
Learning to Select the Relevant History Turns in Conversational Question Answering

Munazza Zaib, Wei Emma Zhang, Quan Z. Sheng et al.

The increasing demand for the web-based digital assistants has given a rapid rise in the interest of the Information Retrieval (IR) community towards the field of conversational question answering (ConvQA). However, one of the critical aspects of ConvQA is the effective selection of conversational history turns to answer the question at hand. The dependency between relevant history selection and correct answer prediction is an intriguing but under-explored area. The selected relevant context can better guide the system so as to where exactly in the passage to look for an answer. Irrelevant context, on the other hand, brings noise to the system, thereby resulting in a decline in the model's performance. In this paper, we propose a framework, DHS-ConvQA (Dynamic History Selection in Conversational Question Answering), that first generates the context and question entities for all the history turns, which are then pruned on the basis of similarity they share in common with the question at hand. We also propose an attention-based mechanism to re-rank the pruned terms based on their calculated weights of how useful they are in answering the question. In the end, we further aid the model by highlighting the terms in the re-ranked conversational history using a binary classification task and keeping the useful terms (predicted as 1) and ignoring the irrelevant terms (predicted as 0). We demonstrate the efficacy of our proposed framework with extensive experimental results on CANARD and QuAC -- the two popularly utilized datasets in ConvQA. We demonstrate that selecting relevant turns works better than rewriting the original question. We also investigate how adding the irrelevant history turns negatively impacts the model's performance and discuss the research challenges that demand more attention from the IR community.

en cs.CL, cs.AI
arXiv Open Access 2023
From Halos to Galaxies. VII. The Connections Between Stellar Mass Growth History, Quenching History and Halo Assembly History for Central Galaxies

Cheqiu Lyu, Yingjie Peng, Yipeng Jing et al.

The assembly of galaxies over cosmic time is tightly connected to the assembly of their host dark matter halos. We investigate the stellar mass growth history and the chemical enrichment history of central galaxies in SDSS-MaNGA. We find that the derived stellar metallicity of passive central galaxies is always higher than that of the star-forming ones. This stellar metallicity enhancement becomes progressively larger towards low-mass galaxies (at a given epoch) and earlier epochs (at a given stellar mass), which suggests strangulation as the primary mechanism for star formation quenching in central galaxies not only in the local universe, but also very likely at higher redshifts up to $z\sim3$. We show that at the same present-day stellar mass, passive central galaxies assembled half of their final stellar mass $\sim 2$ Gyr earlier than star-forming central galaxies, which agrees well with semi-analytic model. Exploring semi-analytic model, we find that this is because passive central galaxies reside in, on average, more massive halos with a higher halo mass increase rate across cosmic time. As a consequence, passive central galaxies are assembled faster and also quenched earlier than their star-forming counterparts. While at the same present-day halo mass, different halo assembly history also produces very different final stellar mass of the central galaxy within, and halos assembled earlier host more massive centrals with a higher quenched fraction, in particular around the "golden halo mass" at $10^{12}\mathrm{M_\odot}$. Our results call attention back to the dark matter halo as a key driver of galaxy evolution.

en astro-ph.GA
DOAJ Open Access 2023
Screening for Influenza and Morbillivirus in Seals and Porpoises in the Baltic and North Sea

Iben Stokholm, Christine Baechlein, Sara Persson et al.

Historically, the seals and harbour porpoises of the Baltic Sea and North Sea have been subjected to hunting, chemical pollutants and repeated mass mortalities, leading to significant population fluctuations. Despite the conservation implications and the zoonotic potential associated with viral disease outbreaks in wildlife, limited information is available on the circulation of viral pathogens in Baltic Sea seals and harbour porpoises. Here, we investigated the presence of the influenza A virus (IAV), the phocine distemper virus (PDV) and the cetacean morbillivirus (CeMV) in tracheal swabs and lung tissue samples from 99 harbour seals, 126 grey seals, 73 ringed seals and 78 harbour porpoises collected in the Baltic Sea and North Sea between 2002–2019. Despite screening 376 marine mammals collected over nearly two decades, we only detected one case of PDV and two cases of IAV linked to the documented viral outbreaks in seals in 2002 and 2014, respectively. Although we find no evidence of PDV and IAV during intermediate years, reports of isolated cases of PDV in North Sea harbour seals and IAV (H5N8) in Baltic and North Sea grey seals suggest introductions of those pathogens within the sampling period. Thus, to aid future monitoring efforts we highlight the need for a standardized and continuous sample collection of swabs, tissue and blood samples across Baltic Sea countries.

arXiv Open Access 2022
The Value of Recycling for Low-Carbon Energy Systems -- a Case Study of Germany's Energy Transition

Felix Kullmann, Peter Markewitz, Leander Kotzur et al.

To achieve climate neutrality, synergies between circular economy and reduction of greenhouse gas emissions must be strengthened. Previously idle emission reduction potentials of resource efficiency are to be exploited. Since all potentially possible emission reduction measures are linked by interactions, the evaluation of a single measure in terms of cost efficiency, effectiveness, and compliance with climate protection targets is very complex and requires a model-based analysis that takes the entire energy system into account. This work advances an energy system model for Germany so that through comprehensive modeling of industrial processes and implementation of recycling options, the impact of recycling measures in the context of national greenhouse gas mitigation strategies can be analyzed. The scenario evaluation shows that different recycling strategies have large effects on the German energy system. Without recycling energy demand in 2050 will increase by more than 300 TWh and cost of transformation will rise by 85% compared to a reference scenario. On the other hand, if maximum recycling rates can be achieved, costs of transformation can be reduced by 26% until 2050. Recycling is an essential and cost-efficient greenhouse gas reduction strategy for future low-carbon energy system designs.

en math.OC
arXiv Open Access 2021
A new perspective of exponential stability for Timoshenko systems under history and thermal effects

Marcio A. Jorge Silva, Sandro B. Pinheiro

We address a Timoshenko system with memory in the history context and thermoelasticity of type III for heat conduction. Our main goal is to prove its uniform (exponential) stability by illustrating carefully the sensitivity of the heat and history couplings on the Timoshenko system. This investigation contrasts previous insights on the subject and promotes a new perspective with respect to the stability of the thermo-viscoelastic problem carried out, by combining the whole strength of history and thermal effects.

en math.AP
DOAJ Open Access 2021
High Blood Flow Into the Femur Indicates Elevated Aerobic Capacity in Synapsids Since the Synapsida-Sauropsida Split

Philipp L. Knaus, Philipp L. Knaus, Philipp L. Knaus et al.

Varanids are the only non-avian sauropsids that are known to approach the warm-blooded mammals in stamina. Furthermore, a much higher maximum metabolic rate (MMR) gives endotherms (including birds) higher stamina than crocodiles, turtles, and non-varanid lepidosaurs. This has led researchers to hypothesize that mammalian endothermy evolved as a second step after the acquisition of elevated MMR in non-mammalian therapsids from a plesiomorphic state of low metabolic rates. In recent amniotes, MMR correlates with the index of blood flow into the femur (Qi), which is calculated from femoral length and the cross-sectional area of the nutrient foramen. Thus, Qi may serve as an indicator of MMR range in extinct animals. Using the Qi proxy and phylogenetic eigenvector maps, here we show that elevated MMRs evolved near the base of Synapsida. Non-mammalian synapsids, including caseids, edaphosaurids, sphenacodontids, dicynodonts, gorgonopsids, and non-mammalian cynodonts, show Qi values in the range of recent endotherms and varanids, suggesting that raised MMRs either evolved in synapsids shortly after the Synapsida-Sauropsida split in the Mississippian or that the low MMR of lepidosaurs and turtles is apomorphic, as has been postulated for crocodiles.

Evolution, Ecology
DOAJ Open Access 2021
Ethics, Patents and Genome Editing: A Critical Assessment of Three Options of Technology Governance

Oliver Feeney, Julian Cockbain, Sigrid Sterckx

Current methods of genome editing have been steadily realising the once remote possibilities of making effective and realistic genetic changes to humans, animals and plants. To underpin this, only 6 years passed between Charpentier and Doudna’s 2012 CRISPR-Cas9 paper and the first confirmed (more or less) case of gene-edited humans. While the traditional legislative and regulatory approach of governments and international bodies is evolving, there is still considerable divergence, unevenness and lack of clarity. However, alongside the technical progress, innovation has also been taking place in terms of ethical guidance from the field of patenting. The rise of so-called “ethical licensing” is one such innovation, where patent holders’ control over genome editing techniques, such as CRISPR, creates a form of private governance over possible uses of gene-editing through ethical constraints built into their licensing agreements. While there are some immediately apparent advantages (epistemic, speed, flexibility, global reach, court enforced), this route seems problematic for, at least, three important reasons: 1) lack of democratic legitimacy/procedural justice, 2) voluntariness, wider/global coordination, and sustainability/stability challenges and 3) potential motivational effects/problems. Unless these three concerns are addressed, it is not clear if this route is an improvement on the longer, slower traditional regulatory route (despite the aforementioned problems). Some of these concerns seem potentially addressed by another emerging patent-based approach. Parthasarathy proposes government-driven regulation using the patent system, which, she argues, has more transparency and legitimacy than the ethical licensing approach. This proposal includes the formation of an advisory committee that would guide this government-driven approach in terms of deciding when to exert control over gene editing patents. There seem to be some apparent advantages with this approach (over traditional regulation and over the ethical licensing approach mentioned above—speed and stability being central, as well as increased democratic legitimacy). However, problems also arise—such as a “half-way house” of global democratic legitimacy that may not be legitimate enough whilst still compromising speed of decision-making under the “ethical licensing” approach). This paper seeks to highlight the various advantages and disadvantages of the three main regulatory options—traditional regulation, ethical licensing and Parthasarathy’s approach—before suggesting an important, yet realistically achievable, amendment of TRIPS and an alternative proposal of a WTO ethics advisory committee.

Political science

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