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ABSTRACTAccurate reconstructed series are crucial for studying the differences in regional hydroclimatic variations in Europe over the past millennium. Using hierarchical clustering analysis and stepwise regression methods, we reconstructed yearly time series of the summer standardized precipitation evapotranspiration index (SPEI) for six European regions over the past millennium. Our analysis also revealed prominent regional hydroclimatic differences in multidecadal signals over the past 500 years. For instance, in the 1500s–1570s (from the beginning of the 1500s to the end of the 1570s), drying trends were observed in northern and southeastern Europe, whereas southwestern Europe experienced a wetting trend. Moreover, drying trends were observed in northern and central Europe in the 1640s–1670s. Additionally, wetting trends were observed in western and central Europe during the 1830s–1850s, with drying trends in northern and southeastern Europe. Notably, the hydroclimatic variations in most European regions showed drying trends in the 1920s–1950s, especially in southern Europe. By utilizing large amounts of tree-ring samples and directly comparing regional hydroclimatic variations, our reconstructions provide a consistent and comprehensive dataset for further analysis. The reconstructed dataset is available at https://doi.org/10.57760/sciencedb.07215.

Since China is the largest developing country in the world, its urban reconstruction has significance for countries undergoing rapid urbanization. The recent development of its central cities has gradually changed from large-scale incremental expansion to stock optimization. District boundary reorganization has become a new trend in reforming China's administrative division of central cities. From the perspective of scalar reorganization and regional reconstruction, the adjustment of urban administrative divisions can be regarded as a regional construction strategy initiated by city governments to reshape the spatial structure, improve the governance relationship, and enhance the cities' competitiveness. This study takes Hangzhou, an important central city in eastern China, as a case study to illustrate two ways in which a central city can optimize its urban spaces through district boundary recombination: scale recombination and regional recombination. The findings demonstrate two advantages of district boundary reorganization for China's central cities: it eases the integration of new city districts and urban areas and promotes balanced development within the city. In the future, more Chinese cities will likely choose to reorganize their district boundaries. [ABSTRACT FROM AUTHOR]

[Display omitted] • A regional chronology of landsliding on the banks of the Váh River has been compiled. • Data from 408 tree-ring series allowed to reveal 45 landslide events. • The spatio-temporal behaviour of landslides was reconstructed. • Spatial analysis revealed specific relationships between landslide and river. Landslides on the banks of meander bends of lower rivers pose a potential risk to the navigability of rivers, but also to their potentially dangerous damming. To properly understand the relationship of river action on the stability of adjacent landslides, it is necessary to analyse the historical evolution and spatial extent of landslide activity. In this study, the results of a regional reconstruction of landslide movements on the lower reaches of the Váh River (central Slovakia) are presented, which allows for a more comprehensive disclosure of the river-slide relationship compared to classical case studies. Using data from a 408 tree-ring series of 204 disturbed trees, 43 reactivations of five landslides were dated over the last ca. 45 years. Analysis of the relationship between the spatial extent of landslide activity and distance from the river revealed that in two cases there was a direct relationship where landslide activity gradually decreased with increasing distance from the river (these were the landslides closest to the river). Given the absence of erosional forms on the riverbank, it is likely that the landslides are not being destabilized by lateral river erosion and the relief of their faces, but rather by the loading of their bodies due to rising groundwater during floods. On the other hand, one landslide (furthest from the river) showed increasing landslide activity towards the main scarp. This pattern is consistent with the retrogressive landslide development generally expected for other landslides in the wider region. For the remaining two landslides, no significant relationship between spatial landslide activity and distance from the river was found, which, however, cannot rule it out, but rather suggests that the influences on the initiation of landslide movements in this case are very complex and probably combine both the influence of groundwater level fluctuations and the occurrence of critical rainfall events. [ABSTRACT FROM AUTHOR]

Since China is the largest developing country in the world, its urban reconstruction has significance for countries undergoing rapid urbanization. The recent development of its central cities has gradually changed from large-scale incremental expansion to stock optimization. District boundary reorganization has become a new trend in reforming China’s administrative division of central cities. From the perspective of scalar reorganization and regional reconstruction, the adjustment of urban administrative divisions can be regarded as a regional construction strategy initiated by city governments to reshape the spatial structure, improve the governance relationship, and enhance the cities’ competitiveness. This study takes Hangzhou, an important central city in eastern China, as a case study to illustrate two ways in which a central city can optimize its urban spaces through district boundary recombination: scale recombination and regional recombination. The findings demonstrate two advantages of district boundary reorganization for China’s central cities: it eases the integration of new city districts and urban areas and promotes balanced development within the city. In the future, more Chinese cities will likely choose to reorganize their district boundaries.

We consider the regional enlarged observability problem for fractional evolution differential equations involving Caputo derivatives. Using the Hilbert Uniqueness Method, we show that it is possible to rebuild the initial state between two prescribed functions only in an internal subregion of the whole domain. Finally, an example is provided to illustrate the theory. [ABSTRACT FROM AUTHOR]

This study reports two multi-century regional reconstructions of annual precipitation based on Pinus ponderosa and P. edulis from four sites in central northern Arizona. It compares standard regional and time-nested methods to generate reconstructions from 1581-2016 C.E. and 1529-2016 C.E., respectively. The strongest climate relationship is a positive correlation between total ring width and 12-month total precipitation ending in July of the growth year. The chronologies account for 50% of the variance of observed annual precipitation in the regional model and 59%, 60%, and 47% and 35% in the nested models. The two reconstructions are highly correlated (Pearson's correlation r > 0.97, p < 0.001) demonstrating that the reconstructions are highly similar over the period common to both reconstructions, with the nested-models' advantage of extending the range of the reconstruction. The precipitation reconstructions are significantly correlated (r=0.66, p<0.001) with the North American Drought Atlas (NADA). [ABSTRACT FROM AUTHOR]

Aggressive disease such as invasive fungal infections or malignancies may necessitate orbital exenteration. The defects of orbital exenteration are often complex involving adjacent structures. Rehabilitation of the orbital exenteration defect poses unique challenges to the reconstructive surgeon. Various options have been described ranging from secondary intention to microvascular free tissue reconstruction. Here the authors review local/regional options for reconstruction of orbital exenteration defects. [ABSTRACT FROM AUTHOR]

We introduce the concept of regional enlarged observability for fractional evolution differential equations involving Riemann⁻Liouville derivatives. The Hilbert Uniqueness Method (HUM) is used to reconstruct the initial state between two prescribed functions, in an interested subregion of the whole domain, without the knowledge of the state.

Objective To review state-of-the-art modifications and advances in soft tissue local and regional flap reconstruction of the oral cavity and to determine the role these techniques play in current practice. Data Sources Review of the literature regarding oral cavity reconstruction. Review Methods The authors describe advances in locoregional reconstructive options and assimilate data from the literature that compare recent advances to the historic standards. Conclusions Modern advances in regional reconstruction of the oral cavity offer outstanding results and demonstrate potential advance over free tissue transfer. These modifications demonstrate the prominent role that regional reconstruction can play in oral cavity reconstruction. Implications for Practice With a more complete understanding of these options, the surgeon is better able to tailor the reconstruction to the needs of the patient to provide high-quality cost-effective care. [ABSTRACT FROM AUTHOR]

To deal with global warming and biodiversity loss, historical land use in South Asia received wide attention because of its huge population and rich biodiversity. We reviewed representative global and regional historical land use reconstructions for South Asia from their data sources, methods of area estimation and spatial mapping, and outcomes. Then we made some prospects on developing historical land use for South Asia. The land use area of South Asia in global reconstructions was mainly estimated using population. For the spatial pattern, most of them assumed that the historical distribution of land use in South Asia mimics satellite-based land use patterns or that the land use area was pixelized based on land suitability for cultivation and grazing. Large discrepancies exist among these global reconstructions in the land use area and spatial patterns with increasing magnitude with time in the past. The regional reconstructions of historical land use for South Asia used more regional historical records, but most covered only about one hundred years. The closer to the past, the lower the spatial-temporal resolution of these regional reconstructions. Great discrepancies also exist between these regional reconstructions because of the differences in cropland definition. Expansion of archaeological data sources, meta-analysis, and crowdsourcing will bring insights into area estimation of historical land use. Remote sensing and machine learning will facilitate spatial pattern mapping. Reconstruction region-by-region, and then integration, is also a solution for current challenges in reconstructing historical land use for South Asia. [ABSTRACT FROM AUTHOR]

Dangerous overland flood events in the foothills of the flysch Carpathians often result from a cumulative effect of floods in high-gradient channels. Detailed understanding of the origin of floods in these catchments is only possible if the occurrence of these floods in the past has thoroughly been studied. Yet, no gauging stations can be found in the local catchments. The reconstruction of floods in ungauged catchments has so far been performed using dendrogeomorphic methods. Stems or branches floating in the floodwater can affect stems or roots of living trees and injure them. Trees are able to record these signals in their tree-ring series. Within the flysch Carpathians, the floods have been reconstructed based on the analysis of 446 cross sections from scarred tree roots and 192 increment cores from the stems of affected trees in the studied area of 10 catchments surrounding the highest peak of the Moravskoslezské Beskydy Mts, the Lysá hora Mt. The dating comprised 64 floods (in different catchments) in 28 flood years for the maximal period of 1883–2012. Most catchments (nine out of ten) were affected by floods in the year 1997. Above-average frequency of floods has also been found for the last two decades, namely thanks to numerous samples taken from young tree roots that revealed more flood impacts. By contrast, although tree-ring series enabled the reconstruction of a longer time series, they only recorded the major floods. The most significant factor affecting the frequency of floods is the orientation of catchments toward the prevailing wind direction. Positive influence of catchment gradient on flood frequency and higher occurrence of floods in the period of intensive slope deforestation show that the floods of the 1950s to 1970s could have a character of flash floods. This assumption is also supported by the character of probable triggering precipitation (high magnitude–short duration precipitation) of this period. Generally, the most frequent probable triggering factor is, however, an above-average seven-day precipitation amount, which indicates — along with the positive relation between the catchment extent and flood frequency — that a majority of floods hardly ever occur as an immediate response to one-day precipitation extremes. Fast spring melting of thick snow cover plays an insignificant role in floods in the studied medium–high mountains. [ABSTRACT FROM AUTHOR]

The aim of this paper is to introduce the concept of observability for distributed parabolic system evolving in spatial domain Ω, and which the state is to be observed between two prescribed functions given only on a boundary subregion of ГΩ. We give definitions and some properties of this kind of regional observability and we describe two approaches to solve this problem where the first is based on subdifferential techniques and the second uses the lagrangian multiplier method. This last approach leads to an algorithm which is performed by numerical example and simulation. [ABSTRACT FROM AUTHOR]

Abstract: General theory of a new reconstruction technique for partially parallel imaging (PPI) is presented in this study. Reconstruction in Image space using Basis functions (RIB) is based on the general principle that the PPI reconstruction in image space can be represented by a pixel-wise weighted summation of the aliased images directly from undersampled data. By assuming that these weighting coefficients for unaliasing can be approximated from the linear combination of a few predefined basis functions, RIB is capable of reconstructing the image within an arbitrary region. This paper discusses the general theory of RIB and its relationship to the classical reconstruction method, GRAPPA. The presented experiments demonstrate RIB with several MRI applications. It is shown that the performance of RIB is comparable to that of GRAPPA. In some cases, RIB shows advantages of increasing reconstruction efficiency, suppressing artifacts and alleviating the nonuniformity of noise distribution. It is anticipated that RIB would be especially useful for cardiac and prostate imaging, where the field of view during data acquisition is required to be much larger than the region of interest. [Copyright &y& Elsevier]

Abstract: The purpose of this paper is to develop the question of regional observability of a system described by the wave equation evolving in spatial domain . It concerns the observability of such a system only on a subregion of . Then we give definitions and characterization of this notion linked with sensors structure and we describe an important approach that estimates the state of the system on a given subregion. The study examines various kind of measurements and sensors. The obtained results are illustrated by numerical examples and simulations. [Copyright &y& Elsevier]

Aggressive disease such as invasive fungal infections or malignancies may necessitate orbital exenteration. The defects of orbital exenteration are often complex involving adjacent structures. Rehabilitation of the orbital exenteration defect poses unique challenges to the reconstructive surgeon. Various options have been described ranging from secondary intention to microvascular free tissue reconstruction. Here the authors review local/regional options for reconstruction of orbital exenteration defects.