9 research outputs found
Phenological shifts of abiotic events, producers and consumers across a continent
Ongoing climate change can shift organism phenology in ways that vary depending on species, habitats and climate factors studied. To probe for large-scale patterns in associated phenological change, we use 70,709 observations from six decades of systematic monitoring across the former Union of Soviet Socialist Republics. Among 110 phenological events related to plants, birds, insects, amphibians and fungi, we find a mosaic of change, defying simple predictions of earlier springs, later autumns and stronger changes at higher latitudes and elevations. Site mean temperature emerged as a strong predictor of local phenology, but the magnitude and direction of change varied with trophic level and the relative timing of an event. Beyond temperature-associated variation, we uncover high variation among both sites and years, with some sites being characterized by disproportionately long seasons and others by short ones. Our findings emphasize concerns regarding ecosystem integrity and highlight the difficulty of predicting climate change outcomes. The authors use systematic monitoring across the former USSR to investigate phenological changes across taxa. The long-term mean temperature of a site emerged as a strong predictor of phenological change, with further imprints of trophic level, event timing, site, year and biotic interactions.Peer reviewe
Chronicles of nature calendar, a long-term and large-scale multitaxon database on phenology
We present an extensive, large-scale, long-term and multitaxon database on phenological and climatic variation, involving 506,186 observation dates acquired in 471 localities in Russian Federation, Ukraine, Uzbekistan, Belarus and Kyrgyzstan. The data cover the period 1890-2018, with 96% of the data being from 1960 onwards. The database is rich in plants, birds and climatic events, but also includes insects, amphibians, reptiles and fungi. The database includes multiple events per species, such as the onset days of leaf unfolding and leaf fall for plants, and the days for first spring and last autumn occurrences for birds. The data were acquired using standardized methods by permanent staff of national parks and nature reserves (87% of the data) and members of a phenological observation network (13% of the data). The database is valuable for exploring how species respond in their phenology to climate change. Large-scale analyses of spatial variation in phenological response can help to better predict the consequences of species and community responses to climate change.Peer reviewe
Does the ripple effect influence the bullwhip effect? An integrated analysis of structural and operational dynamics in the supply chain
International audienc
RuNNE-2022 Shared Task: Recognizing Nested Named Entities
The RuNNE Shared Task approaches the problem of nested named entity
recognition. The annotation schema is designed in such a way, that an entity
may partially overlap or even be nested into another entity. This way, the
named entity "The Yermolova Theatre" of type "organization" houses another
entity "Yermolova" of type "person". We adopt the Russian NEREL dataset for the
RuNNE Shared Task. NEREL comprises news texts written in the Russian language
and collected from the Wikinews portal. The annotation schema includes 29
entity types. The nestedness of named entities in NEREL reaches up to six
levels. The RuNNE Shared Task explores two setups. (i) In the general setup all
entities occur more or less with the same frequency. (ii) In the few-shot setup
the majority of entity types occur often in the training set. However, some of
the entity types are have lower frequency, being thus challenging to recognize.
In the test set the frequency of all entity types is even.
This paper reports on the results of the RuNNE Shared Task. Overall the
shared task has received 156 submissions from nine teams. Half of the
submissions outperform a straightforward BERT-based baseline in both setups.
This paper overviews the shared task setup and discusses the submitted systems,
discovering meaning insights for the problem of nested NER. The links to the
evaluation platform and the data from the shared task are available in our
github repository: https://github.com/dialogue-evaluation/RuNNE.Comment: To appear in Dialogue 202
THE INFLUENCE OF THE MOISTURE CONTENT OF WOOD ON THE STRENGH PROPERTIES OF NAILED CONNECTIONS
Abstract. Objectives It is known that the moisture content of wood has a significant effect on the joint strength of elements of wooden structures. However, there has been little research in establishing a specific relationship between the moisture content of wood and the nailed joint strength of wooden elements. The aim of the study is to determine the influence of capillary (free) and bound (hygroscopic) wood moisture on the strength of nailed connections during pull-out. Methods Conducting experimental studies. Results Three series of samples were tested. For each sample the maximum nail pulling force was determined, with the ultimate pulling resistance calculated according to the formula supplied by the appropriate Rules and Regulations. The samples of the first series were tested with wood having low moisture content. The samples of the second series were moistened prior to the test by being immersed in water for 24 hours to gain capillary moisture. The samples of the third series were moistened prior to the test hygroscopic moisture absorption by being placed in a desiccator above water for a long time without direct contact. Conclusion In the course of the study, it was found that both capillary and hygroscopic moisture significantly affects the strength of nailed connections, and that the effect on the maximum pulling force is not determined by the type of moisture, but by its value. The samples of the first series indicated the greatest nail pulling resistance. The samples of the second series had nail pulling resistance less by 48%. In the third series, the strength of the nailed connection was reduced by 31% as compared to the dry wood. The results of the study confirm the necessity of taking into account the humidity during the design and operation of nailed connections
Copper(II)-Mediated Iodination of 1-Nitroso-2-naphthol
The 3-Iodo-1-nitrosonaphthalene-2-ol (I-NON) was obtained by the copper(II)-mediated iodination of 1-nitroso-2-naphthol (NON). The suitable reactants and optimized reaction conditions, providing 94% NMR yield of I-NON, included the usage of Cu(OAc)2·H2O and 1:2:8 CuII/NON/I2 molar ratio between the reactants. The obtained I-NON was characterized by elemental analyses (C, H, N), high-resolution ESI+-MS, 1H and 13C{1H} NMR, FTIR, UV-vis spectroscopy, TGA, and X-ray crystallography (XRD). The copper(II) complexes bearing deprotonated I-NON were prepared as follows: cis-[Cu(I-NONâH)(I-NON)](I3) (1) was obtained by the reaction between Cu(NON-H)2 and I2 in CHCl3/MeOH, while trans-[Cu(I-NONâH)2] (2) was synthesized from I-NON and Cu(OAc)2 in MeOH. Crystals of trans-[Cu(I-NONâH)2(THF)2] (3) and trans-[Cu(I-NONâH)2(Py)2] (4) were precipitated from solutions of 2 in CHCl3/THF and Py/CHCl3/MeOH mixtures, respectively. The structures of 1 and 3â4 were additionally verified by X-ray crystallography. The characteristic feature of the structures of 1 and 3 is the presence of intermolecular halogen bonds with the involvement of the iodine center of the metal-bound deprotonated I-NON. The nature of the I···I and I···O contacts in the structures of 1 and 3, correspondingly, were studied theoretically at the DFT (PBE0-D3BJ) level using the QTAIM, ESP, ELF, NBO, and IGM methods
Differences in spatial versus temporal reaction norms for spring and autumn phenological events
For species to stay temporally tuned to their environment, they use cues such as the accumulation of degree-days. The relationships between the timing of a phenological event in a population and its environmental cue can be described by a population-level reaction norm. Variation in reaction norms along environmental gradients may either intensify the environmental effects on timing (cogradient variation) or attenuate the effects (countergradient variation). To resolve spatial and seasonal variation in species' response, we use a unique dataset of 91 taxa and 178 phenological events observed across a network of 472 monitoring sites, spread across the nations of the former Soviet Union. We show that compared to local rates of advancement of phenological events with the advancement of temperature-related cues (i.e., variation within site over years), spatial variation in reaction norms tend to accentuate responses in spring (cogradient variation) and attenuate them in autumn (countergradient variation). As a result, among-population variation in the timing of events is greater in spring and less in autumn than if all populations followed the same reaction norm regardless of location. Despite such signs of local adaptation, overall phenotypic plasticity was not sufficient for phenological events to keep exact pace with their cues-the earlier the year, the more did the timing of the phenological event lag behind the timing of the cue. Overall, these patterns suggest that differences in the spatial versus temporal reaction norms will affect species' response to climate change in opposite ways in spring and autumn