355 research outputs found
Spiders of Iran – Systematics, diversity and distribution
Spiders (Araneae) are the largest order of Arachnida and the sixth most speciose order of Animalia, comprising more than 50,000 extant species as well as over 1,400 species known from fossils. Despite this immense diversity that has been estimated to comprise 120,000–200,000 species, our knowledge of their systematics and distribution remains rather incipient. While attempts to evaluate the diversity and distribution patterns of spiders have been made for the Neotropical and a few other faunas, most other regions remain historically neglected.
The aim of this dissertation is to explore the systematics, diversity and distribution of spiders of Iran, a highly interesting region from a zoological and biogeographical point of view that unfortunately has been poorly investigated regarding its invertebrate fauna. For this purpose, I examined more than 9,000 specimens that were either collected during expeditions to numerous regions and ecosystems across the country or deposited in several natural history collections from around the world. As a result of these efforts, which were initiated in 2013 and mostly carried out in collaboration with researchers from various countries, a total of 11 genera and 147 species of Iranian spiders were described as new to science, and 419 taxa (i.e., 13 families, 87 genera and 319 species) were recorded in Iran for the first time. The total number of newly described and recorded species (i.e., 466 species) constitutes almost half (i.e., 49.83%) of the currently known Iranian species diversity of this group (i.e., 935 species). Amongst 147 species described, 137 are known only from Iran, representing 63.72% of all species currently considered endemic to this country (i.e., 215 species). These results were published in a total of 87 publications, 38 of which were published after the beginning of my doctoral studies at UTU in 2019. This dissertation, however, is primarily based on only nine taxonomic articles (i.e., I–IX), all published after 2019 and highlighting some of the more important findings.
Because of the newly obtained taxonomic information and an extensive database of all published records, it was possible to conduct a comprehensive review of spatial variation in the diversity patterns of spiders in Iran. This was the main objective of publication X, which also included an evaluation of the effect of sampling bias on the current understanding of the distribution of Iranian spiders. The analyses showed that the diversity of Iranian spiders remains inadequately studied and is heavily affected by the Linnean shortfall (i.e., gaps in taxonomic knowledge), despite a remarkable improvement in taxonomic research on this fauna since the beginning of the 21st century. There are 935 spider species in the 1,648,195 km2 of Iran. Comparing the number of species per area of 171 countries and other political regions indicated that Iran was in position 132, whereas many considerably smaller and less ecologically diverse countries were in lower positions. It was also found that this fauna clearly suffers from a severe Wallacean shortfall (i.e., lack of knowledge of species distributions), as approximately 85% of Iran lacks a single record of spiders. There is a highly uneven distribution of records throughout the country and its provinces and ecoregions, with most of the records situated near large cities. A high correlation was found between the number of records of spiders and the number of records of plants and other animals in Iran, indicating that the noted shortfalls are indeed corroborated by other taxa. Finally, it is suggested that to gain a more complete picture of the diversity of Iranian spiders, future collecting efforts should be primarily in the form of extensive systematic surveys instead of opportunistic sampling, and ideally targeting lesser sampled areas and ecoregions. Once a satisfactory amount of information regarding the taxonomy and distribution of species becomes available, it will be possible to properly assess the conservation status and risk factors that affect these species and to identify areas of higher conservation and management priority.---
Hämähäkit (Araneae) ovat lajimäärältään hämähäkkieläinten suurin lahko, ja kuudenneksi suurin eläinlahko. Lahkoon kuuluu yli 50 000 nykyisin elävää lajia ja yli 1400 lajia jotka tunnetaan fossiileista. Tästä valtavasta, arviolta 120 000 – 200 000 lajin monimuotoisuudesta huolimatta, on tietämys hämähäkkien systematiikasta ja levinneisyyksistä alkutekijöissään. Neotropiikin ja joidenkin muiden alueiden hämäkkien monimuotoisuutta ja lajien levinneisyyksiä on yritetty selvittää, mutta useimmat muut alueet ovat jääneet huomiotta.
Tämän väitöskirjan tavoitteena on tutkia Iranin hämäkkien systematiikkaa, monimuotoisuutta ja lajien levinneisyyksiä. Iran on eläintieteellisesti ja eliömaantieteellisesti kiinnostava alue, jonka selkärangattomien lajisto on jäänyt valitettavan vähälle huomiolle. Tarkastelin yli 9000 näytettä jotka oli joko kerätty tutkimusretkillä Iranissa lukuisilla alueilla ja lukuisissa ekosysteemeissä, tai jotka kuuluivat useisiin eri puolilla maailmaa sijaitseviin luonnontieteellisiin kokoelmiin. Tämä tarkastelu, joka alkoi 2013 ja toteutettiin useimmiten yhteistyössä muiden maiden tutkijoiden kanssa, johti 11 iranilaisen suvun ja 147 lajin kuvaamiseen tieteelle uusina. 419 taksonia (eli 13 heimoa, 87 sukua ja 319 lajia) havaittiin Iranissa ensimmäistä kertaa. Uudet lajit (yhteensä 466 lajia) muodostavat lähes puolet (49.83%) Iranin tunnetusta lajistosta (935 lajia). Tulokset julkaistiin 87 julkaisussa, joista 38 julkaistiin aloitettuani jatko-opintoni Turun yliopistolla 2019. Väitöskirjani perustuu kuitenkin pääosin vain yhdeksään taksonomiseen julkaisuun (I–IX), jotka kaikki julkaistiin vuoden 2019 jälkeen, ja jotka tuovat esille osan tärkeimmistä havainnoista.
Uudet tiedot hämähäkkien taksonomiasta sekä kaikkien julkaistujen havaintojen sijoittaminen tietokantaan mahdollistivat kattavan katsauksen hämähäkkien monimuotoisuuden maantieteellisestä jakautumasta Iranissa. Tämä oli julkaisun X pääsisältö. Julkaisussa arvioitiin myös otantaharhan vaikutusta nykytietämykseen Iranin hämähäkkilajien levinneisyyksistä. Iranin hämähäkkien monimuotoisuus osoittautui puutteellisesti tutkituksi ja lajisto huonosti tunnetuksi, vaikka hämähäkkeihin kohdistuva taksonominen tutkimus on merkittävästi laajentunut sitten 2000-luvun alun. Iranissa on 935 hämähäkkilajia 1,648,195 km2 pinta-alalla. Lajimäärän vertailu pinta-alaa kohti 171 valtiossa tai muulla hallinnollisella alueella sijoitti Iranin sijalle 132, huonompaan sijoitukseen kuin monet pienemmät ja muutoin lajistoltaan vähemmän monimuotoiset maat. Tietämys Iranin hämähäkkilajien levinneisyyksistä osoittautui myös äärimmäisen puutteelliseksi, sillä hämähäkkihavaintoja ei ole yhtäkään noin 85%:ssa Irania. Havainnot jakautuvat erittäin epätasaisesti koko maassa sekä sen provinseissa ja ekoalueilla, sijoittuen pääosin lähelle suuria kaupunkeja. Hämähäkkihavaintojen määrä korreloi vahvasti kasvihavaintojen ja muiden eläinten havaintojen kanssa, viitaten siihen että hämähäkkitietämyksen puutteet vastaavat muiden eliöryhmien tietämyksen puutteita. Lopuksi esitetään, että paremman kuvan saaminen Iranin hämähäkkilajistosta vaatii tulevilta keruutapahtumilta laajaa, systemaattista otostusta sattumanvaraisen ja pienimuotoisen otostuksen sijaan. Ideaalisesti otostus kohdistuisi vähemmän tutkittuihin alueisiin ja ekoalueisiin. Riittävän taksonomisen tiedon ja levinneisyystiedon saaminen tulee sallimaan sekä lajiston suojelutason että lajeihin kohdistuvien riskien arvioimisen, jolloin voidaan tunnistaa luonnonsuojelullisesti tärkeimmät alueet
Controlled shadowing property
[EN] In this paper we introduce a new notion, named controlled shadowing property and we relate it to some notions in dynamical systems such as topological ergodicity, topologically mixing and specication properties. The relation between the controlled shadowing and chaos in sense of Li-Yorke is studied. At the end we give some examples to investigate the controlled shadowing property.Zamani Bahabadi, A. (2018). Controlled shadowing property. Applied General Topology. 19(1):91-99. doi:10.4995/agt.2018.7731SWORD919919
A new species of Draconarius Ovtchinnikov, 1999 (Araneae, Agelenidae) from northeastern Pakistan
A new species of agelenid spiders, Draconarius nathiagalicus sp. nov., is described and illustrated on the basis of two male specimens collected in Nathia Gali, northeastern Pakistan. This is the fourth species of the genus reported from this country, all belonging to the venustus species-group.</p
Evolution of novel material properties and the emergence of group-level heritability in the transition to multicellularity
Evolutionary Transitions in Individuality (ETIs) describe the history of increasing complexity of life and emergence of hierarchical organization in an elegant framework. Each transition is characterized by a group of independent individuals coming together and forming a group that eventually can undergo Darwinian evolution and turns into a new individual level. One of the prominent examples of ETIs is the emergence of multicellularity. In this thesis I address two key questions about the transition to multicellularity: The emergence of heritability of higher level traits and its relationship to cell-level traits.
First, I discuss how the heritability of newly-formed group traits emerges as groups emerge. We introduce a simple theoretical model for calculating group-level trait heritability, where the trait is the linear function of a cell-level trait. For cases in which the relationship is more complex than a linear function, we developed a statistical simulation to model and explore different kinds of analytical functions based on biological examples of relationship between cell-level traits and collective-level traits. Finally, using the snowflake yeast model system we did an experiment that shows an ecologically relevant, emergent trait in a nascent multicellular organism can have a higher heritability across a range of conditions than the unicellular-level trait on which it is based. The evolution of complex multicellularity presents an apparent paradox: nascent multicellular organisms are thought to require (relatively) large size to evolve complex traits, but at the same time maintaining large size requires complex organization at the cell and group levels. This poses a chicken and egg problem between large size and cellular development. Here, we show that over the course of a year snowflake yeast can increase its size multiple orders of magnitude with minimal change at the cell level by taking advantage of the physical properties of granular entangled materials.Ph.D
Pre-Training Multi-Modal Dense Retrievers for Outside-Knowledge Visual Question Answering
This paper studies a category of visual question answering tasks, in which
accessing external knowledge is necessary for answering the questions. This
category is called outside-knowledge visual question answering (OK-VQA). A
major step in developing OK-VQA systems is to retrieve relevant documents for
the given multi-modal query. Current state-of-the-art asymmetric dense
retrieval model for this task uses an architecture with a multi-modal query
encoder and a uni-modal document encoder. Such an architecture requires a large
amount of training data for effective performance. We propose an automatic data
generation pipeline for pre-training passage retrieval models for OK-VQA tasks.
The proposed approach leads to 26.9% Precision@5 improvements compared to the
current state-of-the-art asymmetric architecture. Additionally, the proposed
pre-training approach exhibits a good ability in zero-shot retrieval scenarios
Temporal Volatility Surface Projection: Parametric Surface Projection Method for Derivatives Portfolio Risk Management
This study delves into the intricate realm of risk evaluation within the
domain of specific financial derivatives, notably options. Unlike other
financial instruments, like bonds, options are susceptible to broader risks. A
distinctive trait characterizing this category of instruments is their
non-linear price behavior relative to their pricing parameters. Consequently,
evaluating the risk of these securities is notably more intricate when
juxtaposed with analogous scenarios involving fixed-income instruments, such as
debt securities. A paramount facet in options risk assessment is the inherent
uncertainty stemming from first-order fluctuations in the underlying asset's
volatility. The dynamic patterns of volatility fluctuations manifest striking
resemblances to the interest rate risk associated with zero-coupon bonds.
However, it is imperative to bestow heightened attention on this risk category
due to its dependence on a more extensive array of variables and the temporal
variability inherent in these variables. This study scrutinizes the
methodological approach to risk assessment by leveraging the implied volatility
surface as a foundational component, thereby diverging from the reliance on a
singular estimate of the underlying asset's volatility
A Symmetric Dual Encoding Dense Retrieval Framework for Knowledge-Intensive Visual Question Answering
Knowledge-Intensive Visual Question Answering (KI-VQA) refers to answering a
question about an image whose answer does not lie in the image. This paper
presents a new pipeline for KI-VQA tasks, consisting of a retriever and a
reader. First, we introduce DEDR, a symmetric dual encoding dense retrieval
framework in which documents and queries are encoded into a shared embedding
space using uni-modal (textual) and multi-modal encoders. We introduce an
iterative knowledge distillation approach that bridges the gap between the
representation spaces in these two encoders. Extensive evaluation on two
well-established KI-VQA datasets, i.e., OK-VQA and FVQA, suggests that DEDR
outperforms state-of-the-art baselines by 11.6% and 30.9% on OK-VQA and FVQA,
respectively. Utilizing the passages retrieved by DEDR, we further introduce
MM-FiD, an encoder-decoder multi-modal fusion-in-decoder model, for generating
a textual answer for KI-VQA tasks. MM-FiD encodes the question, the image, and
each retrieved passage separately and uses all passages jointly in its decoder.
Compared to competitive baselines in the literature, this approach leads to
5.5% and 8.5% improvements in terms of question answering accuracy on OK-VQA
and FVQA, respectively
AAGLMES: an intelligent expert system realization of adaptive autonomy using generalized linear models
Abstract—We earlier introduced a novel framework for
realization of Adaptive Autonomy (AA) in human-automation
interaction (HAI). This study presents an expert system for
realization of AA, using Support Vector Machine (SVM),
referred to as Adaptive Autonomy Support Vector Machine
Expert System (AASVMES). The proposed system prescribes
proper Levels of Automation (LOAs) for various
environmental conditions, here modeled as Performance
Shaping Factors (PSFs), based on the extracted rules from the
experts’ judgments. SVM is used as an expert system inference
engine. The practical list of PSFs and the judgments of
GTEDC’s (the Greater Tehran Electric Distribution
Company) experts are used as expert system database. The
results of implemented AASVMES in response to GTEDC’s
network are evaluated against the GTEDC experts’ judgment.
Evaluations show that AASVMES has the ability to predict the
proper LOA for GTEDC’s Utility Management Automation
(UMA) system, which changes in relevance to the changes in
PSFs; thus providing an adaptive LOA scheme for UMA.
Keywords-Support Vector Machine (SVM); Adaptive
Autonomy (AA); Expert System; Human Automation Interaction
(HAI); Experts’ Judgment; Power System; Distribution
Automation; Smart Grid
The spider family Oecobiidae (Arachnida: Araneae) in Iran, Afghanistan and Turkmenistan
The taxonomic and faunistic status of the spider family Oecobiidae in
Iran, Afghanistan and Turkmenistan is revised. A new species, namely
Uroctea gambronica sp. nov. (♂) is described from southern Iran, and the
male of U. grossa Roewer, 1960 is described and illustrated for the
first time. Additionally, new faunistic data are provided, including the
first records of Oecobius putus O. Pickard-Cambridge, 1876 and U.
grossa in Afghanistan and Turkmenistan, respectively, and the
re-evaluation of previously misidentified and questionable records of
this family in the region. The known distribution ranges of all species
are mapped for these three countries.</p
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