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Using fractal dimension analysis to assess the effects of normal aging and sex on subregional cortex alterations across the lifespan from a Chinese dataset

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CEREBRAL CORTEX 2023年第9期33卷 5289-5296页

作者： Chen, Yiyong Zuo, Yizhi Kang, Shaofang Pan, Liliang Jiang, Siyu Yan, Aohui Li, Lin Ningbo Univ Sch Med Ningbo 315211 Zhejiang Peoples R China Nanjing Med Univ Human Anatomy Dept Nanjing 211166 Jiangsu Peoples R China Ningbo Univ Coll Teacher Educ Ningbo 315211 Zhejiang Peoples R China

Fractal dimension (FD) is used to quantify brain structural complexity and is more sensitive to morphological variability than other cortical measures. However, the effects of normal aging and sex on FD are not fully understood. In this study, age- and sex-related differences in FD were investigated in a sample of 448 adults age of 19-80 years from a Chinese dataset. The FD was estimated with the surface-based morphometry (SBM) approach, sex differences were analyzed on a vertex level, and correlations between FD and age were examined. generalized additive models (GAMs) were used to characterize the trajectories of age-related changes in 68 regions based on the Desikan-Killiany atlas. The SBM results showed sex differences in the entire sample and 3 subgroups defined by age. GAM results demonstrated that the FD values of 51 regions were significantly correlated with age. The trajectories of changes can be classified into 4 main patterns. Our results indicate that sex differences in FD are evident across developmental stages. Age-related trajectories in FD are not homogeneous across the cerebral cortex. Our results extend previous findings and provide a foundation for future investigation of the underlying mechanism.

关键词： fractal dimension Desikan-Killiany atlas generalized additive models

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A novel dynamic rockfall susceptibility model including precipitation, temperature and snowmelt predictors: a case study in Aosta Valley (northern Italy)

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LANDSLIDES 2023年第10期20卷 2131-2154页

作者： Bajni, Greta Camera, Corrado A. S. Apuani, Tiziana Univ Milan Dipartimento Sci Terra A Desio Via Mangiagalli 34 I-20133 Milan Italy

The overarching goal of the study was the development of a potentially dynamic rockfall susceptibility model by including climate predictors. The work is based on previously defined critical thresholds relating three climate indices - effective water inputs (EWI), wet-dry cycles (WD) and freeze-thaw cycles (FT) - and rockfall occurrence. The pilot area is located in the Aosta Valley region (Italian Western Alps). The susceptibility model settings were optimized through a stepwise procedure, carried out by means of generalized additive models (GAM). Predictors included topographic, climatic and additional snow-related variables. As climatic predictors, the mean annual threshold exceedance frequency was calculated for each index. All models were developed including an automatic penalization of statistically non-significant variables (i.e. shrinkage). The initial susceptibility model was set without considering potential inventory bias. Secondly, a "visibility mask" was produced to limit the modelling domain according to the rockfall event census procedures. Thirdly, GAMs functional relationships were analysed to verify the physical plausibility of predictors. Finally, to reduce concurvity, a principal component analysis (PCA) including climatic and snow-related predictors was carried out. Key findings were as follows: (i) ignoring inventory bias led to excellent model performance but to physically implausible outputs;(ii) the selection of non-rockfall points inside a "visibility mask" is effective in managing inventory bias influence on outputs;(iii) the inclusion of climate predictors resulted in an improvement of the physical interpretability of the associated models and susceptibility maps, being EWI, WD and the maximum cumulated snow melting the most important physically plausible climate predictors;(iv) the PCA strategy can efficiently reduce model concurvity.

关键词： Alps Threshold exceedance frequency Climate variables Inventory bias generalized additive models Principal component analysis

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Exploring the effects of wildfire events on movement patterns

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APPLIED GEOGRAPHY 2025年 179卷

作者： Noi, Evgeny Dodge, Somayeh Murray, Alan T. Univ Calif Santa Barbara Dept Geog St Barbara CA USA

Natural and man-made disasters have a significant impact on movement patterns, yet existing studies often focus on aggregate-level trends, overlooking the heterogeneity of mobility responses within and across communities. A critical gap remains in understanding the nuanced impacts of wildfires on localized, fine-scale human mobility patterns, particularly how factors such as proximity to the fire, socio-demographic characteristics, and infrastructure shape movement responses. In this paper, we address this gap by analyzing human movement patterns during the wildfire seasons from 2018 to 2020 in California Spatial analytics are used to examine movement flows around twelve wildfire events and map the evolution of their spatio-temporal patterns in response to these disruptive events. To quantify and assess the magnitude of changes in movement patterns between fire and non-fire years, we employ a structural similarity metric. In doing so, we identify the points of influence corresponding to the onset of the fire and the subsequent recovery period. Finally, we characterize variations between fire events and identify the wildfires that had the most significant impact on movement patterns. The findings demonstrate the complexity of movement responses to the wildfires, highlighting the intricate interactions between visitation patterns and the built environment.

关键词： Wildfires Human movement generalized additive models Spatio-temporal analysis

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Amplification of annual and diurnal cycles of alpine lightning

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CLIMATE DYNAMICS 2023年第9-10期61卷 4125-4137页

作者： Simon, Thorsten Mayr, Georg J. Morgenstern, Deborah Umlauf, Nikolaus Zeileis, Achim Univ Innsbruck Dept Math Technikerstr 21a A-6020 Innsbruck Austria Univ Innsbruck Dept Stat Univ Str 15 A-6020 Innsbruck Austria Univ Innsbruck Dept Atmospher & Cryospher Sci Innrain 52 A-6020 Innsbruck Austria

The response of lightning to a changing climate is not fully understood. Historic trends of proxies known for fostering convective environments suggest an increase of lightning over large parts of Europe. Since lightning results from the interaction of processes on many scales, as many of these processes as possible must be considered for a comprehensive answer. Recent achievements of decade-long seamless lightning measurements and hourly reanalyses of atmospheric conditions including cloud micro-physics combined with flexible regression techniques have made a reliable reconstruction of cloud-to-ground lightning down to its seasonally varying diurnal cycle feasible. The European Eastern Alps and their surroundings are chosen as reconstruction region since this domain includes a large variety of land-cover, topographical and atmospheric circulation conditions. The most intense changes over the four decades from 1980 to 2019 occurred over the high Alps where lightning activity doubled in the 2010 s compared to the 1980 s. There, the lightning season reaches a higher maximum and starts one month earlier. Diurnally, the peak is up to 50% stronger with more lightning strikes in the afternoon and evening hours. Signals along the southern and northern alpine rim are similar but weaker whereas the flatlands surrounding the Alps have no significant trend.

关键词： Lightning location system ERA5 Climate change generalized additive models Machine learning Complex terrain

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Traditional summer habitat use by Southern Resident killer whales in the Salish Sea is linked to Fraser River Chinook salmon returns

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MARINE MAMMAL SCIENCE 2023年第3期39卷 858-875页

作者： Stewart, Joshua D. Cogan, Jane Durban, John W. Fearnbach, Holly Ellifrit, David K. Malleson, Mark Pinnow, Melisa Balcomb, Kenneth C. Oregon State Univ Hatfield Marine Sci Ctr Dept Fisheries Wildlife & Conservat Sci Ocean Ecol LabMarine Mammal Inst Corvallis OR USA SR3 SeaLife Response Rehabil & Res Marine Mammal Res Program Washington DC USA Ctr Whale Res Washington DC USA

Southern Resident killer whales (SRKW, Orcinus orca) are a small, endangered population of fish-eating killer whales that inhabit coastal and inland waters of the western United States and British Columbia. SRKW have been in decline since 1995, with food availability, vessel disturbance, and pollutants proposed as drivers of their decline. We used 17 years of sightings data from the SRKW core summer habitat in the Salish Sea to examine trends in presence of SRKW, and how these trends may be related to the availability of a key food source, Fraser River-origin Chinook salmon. We found that SRKW occupancy has declined by more than 75%, in step with reduced average catch per unit effort (CPUE) of Fraser River Chinook salmon. J pod was present in the core summer habitat most often, followed by K and L pods. All three pods demonstrated declines in visitation to the core summer habitat from 2004 to 2020, and presence of SRKW was significantly related to annual average Fraser Chinook CPUE. Our findings suggest that declining Fraser River Chinook returns may be reaching a point where SRKW cannot reliably meet their energetic needs, driving them to forage in areas outside of their traditional core summer habitat.

关键词： food limitation generalized additive models killer whale Orcinus orca predator-prey dynamics

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Insect herbivory following fire on Lyonia fruticosa, an ericaceous shrub of Florida scrub

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FLORIDA ENTOMOLOGIST 2023年第1期106卷 10-15页

作者： Dole, Haley E. Menges, Eric S. David, Aaron S. Plant Ecol Program Archbold Biol Stn Venus FL 33960 USA Univ Nevada Dept Biol MS 3141664 North Virginia St Reno NV 89557 USA

The influential role of fire in shaping Florida scrub vegetation is well documented;however, relatively less is known about the role of fire on trophic interactions such as those between plants and herbivores. Here we examined the response of insect herbivory to time-since-fire and succession on Lyonia fruticosa (Michx.) G.S. Torr. (Ericaceae), a shrub found in scrub of south-central Florida. We measured herbivory on > 200 plants across a time-since-fire gradient of 7 sites (ranging from 0.6-8.7 yr) by (1) surveying recently flushed leaves for 3 mo to control for leaf age, and (2) surveying herbivory across whole plants irrespective of leaf age. We also recorded damage types (chewing, scraping, and mining) to determine how herbivore guilds were affected by time-since-fire. Using generalized additive models, we found herbivory increased for 5 to 6 yr post-fire with 59.8% of the devi-ance explained by time-since-fire in flushed leaf surveys and 76.6% in whole plant surveys. Chewing was the dominant damage type and increased for 5 yr post-fire. Scraping and mining damage were less frequent and unaffected by time-since-fire within the range studied. Additionally, we modeled the post-fire responses of L. fruticosa traits (height, stems, flowering, and leaf area), and found that most changes in growth and reproduction oc-curred within the first 4 to 6 yr post-fire. Herbivory levels increased as plants recovered and peaked in yr 5 and 6 post-fire indicating insect herbivores, like the plants, are well adapted to the dynamic, pyrogenic landscape.

关键词： arthropod plant damage recovery disturbance generalized additive models

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Meta-learning Loss Functions of Parametric Partial Differential Equations Using Physics-Informed Neural Networks 27th

Meta-learning Loss Functions of Parametric Partial Different...

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27th International Conference on Discovery Science

作者： Koumpanakis, Michail Vilalta, Ricardo Univ Houston Dept Comp Sci Houston TX 77204 USA Univ Austin Ctr Sci Technol Engn & Math Austin TX USA

ISBN: (纸本)9783031789762;9783031789779

This paper proposes a new way to learn Physics-Informed Neural Network loss functions using generalized additive models. We apply our method by meta-learning parametric partial differential equations, PDEs, on Burger's and 2D Heat Equations. The goal is to learn a new loss function for each parametric PDE using meta-learning. The derived loss function replaces the traditional data loss, allowing us to learn each parametric PDE more efficiently, improving the meta-learner's performance and convergence.

关键词： Machine Learning Physics Informed Neural Networks Meta-Learning generalized additive models

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Use generalized linear models or generalized partially linear models?

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STATISTICS AND COMPUTING 2023年第5期33卷 1-10页

作者： Li, Xinmin Liang, Haozhe Haerdle, Wolfgang Liang, Hua Qingdao Univ Sch Math & Stat Qingdao 266071 Shandong Peoples R China Univ Sci & Technol China Dept Stat & Finance Hefei 230026 Anhui Peoples R China Humboldt Univ Inst Stat & Okonometrie D-10178 Berlin Germany George Washington Univ Dept Stat Washington DC 20052 USA

We propose test statistics based on the penalized spline to decide between generalized linear models and generalized partially linear models. The numerical performance of the proposed statistics is comparable to that of their kernel-based competitors, which have been shown to be asymptotically normal in the literature (Hardle et al. in J Am Stat Assoc 93:1461-1474, 1998). We also numerically explore the possibility of using the proposed statistics for goodness of fit checking for GLM. The proposed proposed procedures are illustrated to analyze two datasets.

关键词： Backfitting generalized additive models Goodness-of-fit Penalized spline Profile likelihood Quasi-likelihood

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Longitudinal analyses of depression, anxiety, and suicidal ideation highlight greater prevalence in the northern Dutch population during the COVID-19 lockdowns

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JOURNAL OF AFFECTIVE DISORDERS 2023年第0期323卷 62-70页

作者： Ori, Anil P. S. Wieling, Martijn van Loo, Hanna M. Univ Groningen Univ Med Ctr Groningen Dept Psychiat Groningen Netherlands Univ Groningen Univ Med Ctr Groningen Dept Genet Groningen Netherlands Univ Groningen Dept Informat Sci Groningen Netherlands Univ Med Ctr Groningen Dept Psychiat POB 30 001 CC44 NL-9700 RB Groningen Netherlands

Background: The pandemic of the coronavirus disease 2019 (COVID-19) has led to an increased burden on mental health. Aims: To investigate the development of major depressive disorder (MDD), generalized anxiety disorder (GAD), and suicidal ideation in the Netherlands during the first fifteen months of the pandemic and three nation-wide lockdowns. Method: Participants of the Lifelines Cohort Study -a Dutch population-based sample-reported current symptoms of MDD and GAD, including suicidal ideation, according to DSM-IV criteria. Between March 2020 and June 2021, 36,106 participants (aged 18-96) filled out a total of 629,811 questionnaires across 23 time points. Trajectories over time were estimated using generalized additive models and analyzed in relation to age, sex, and lifetime history of MDD/GAD. Results: We found non-linear trajectories for MDD and GAD with a higher number of symptoms and prevalence rates during periods of lockdown. The point prevalence of MDD and GAD peaked during the third hard lockdown at 2.88 % (95 % CI: 2.71 %-3.06 %) and 2.92 % (95 % CI: 2.76 %-3.08 %), respectively, in March 2021. Women, younger adults, and participants with a history of MDD/GAD reported significantly more symptoms. For suicidal ideation, we found a significant linear increase over time in younger participants. For example, 20-year-old participants reported 4.14x more suicidal ideation at the end of June 2021 compared to the start of the pandemic (4.64 % (CI: 3.09 %-6.96 %) versus 1.12 % (CI: 0.76 %-1.66 %)). Limitations: Our findings should be interpreted in relation to the societal context of the Netherlands and the public health response of the Dutch government during the pandemic, which may be different in other regions in the world. Conclusions: Our study showed greater prevalence of MDD and GAD during COVID-19 lockdowns and a continuing increase in suicidal thoughts among young adults suggesting that the pandemic and government enacted restrictions impacted mental h

关键词： Major depressive disorder generalized anxiety disorder Suicidal ideation COVID-19 Lifelines biobank generalized additive models

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Seasonal occurrence and environmental drivers of pelagic shark species in Los Cabos, Mexico, assessed using citizen science

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ENVIRONMENTAL BIOLOGY OF FISHES 2023年第7期106卷 1551-1567页

作者： Pavia, Clara E. Calatayud Suarez, Francisco Mascareno Brunetti, Jacopo Eliceche, Miguel Ayres, Kathryn A. Mexico Azul Ave Mexico 141 Mexico City 04100 Mexico Cabo Shark Dive Blvd Paseo Marina Cabo San Lucas 23450 Baja Calif Sur Mexico

The Mexican Pacific is an area of high biodiversity due to its transitional location of both tropical and sub-tropical waters and many shark species inhabit the coastal areas of Los Cabos off the Baja California Peninsula, Mexico. Here, we used citizen science onboard a local shark tourism operator to determine the probability of pelagic shark presence relative to environmental factors using generalized additive models (GAMs) over a 3-year sampling period. Short-fin mako shark (Isurus oxyrinchus) presence had significant relationships with sea surface temperature (SST), wind speed, sampling site, and year. Smooth hammerhead shark (Sphyrna zygaena) presence was significantly influenced by wind speed, year, photoperiod, moon illumination, and SST. Silky shark (Carcharhinus falciformis) presence had significant relationships with SST, wind speed, site, and year. The use of a tourism operator allowed citizens to be involved in science and provided a platform to collect data. This monitoring program will be continued and provides a baseline dataset of pelagic shark species which can often be lacking from the local artisanal fisheries that target sharks in the area.

关键词： generalized additive models Elasmobranchs Seasonality Provisioning Shark tourism

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