LIVIVO - The Search Portal for Life Sciences

zur deutschen Oberfläche wechseln
Advanced search

Search results

Result 1 - 10 of total 14

Search options

  1. Article: Automatic particle detectors lead to a new generation in plant diversity investigation

    ŠAULIENĖ, Ingrida / ŠUKIENĖ, Laura / DAUNYS, Gintautas / VALIULIS, Gediminas / VAITKEVIČIUS, Lukas

    Notulae botanicae Horti Agrobotanici Cluj-Napoca. 2021, v. 49, no. 3

    2021  

    Abstract: Technological progress in modern scientific development generates opportunities that create new ways to learn more about objects and systems of nature. An important indicator in choosing research methods is not only accuracy but also the time and human ... ...

    Abstract Technological progress in modern scientific development generates opportunities that create new ways to learn more about objects and systems of nature. An important indicator in choosing research methods is not only accuracy but also the time and human resources required to achieve results. This research demonstrates the possibilities of using an automatic particle detector that works based on scattered light pattern and laser-induced fluorescence for plant biodiversity investigation. Airborne pollen data were collected by two different devices, and results were analysed in light of the application for plant biodiversity observation. This paper explained the possibility to gain knowledge with a new type of method that would enable biodiversity monitoring programs to be extended to include information on the diversity of airborne particles of biological origin. It was revealed that plant conservation could be complemented by new tools to test the effectiveness of management plans and optimise mitigation measures to reduce impacts on biodiversity.
    Keywords fluorescence ; humans ; pollen ; species diversity
    Language English
    Publishing place AcademicPres
    Document type Article
    ZDB-ID 2271404-2
    ISSN 1842-4309 ; 0255-965X
    ISSN (online) 1842-4309
    ISSN 0255-965X
    DOI 10.15835/nbha49312444
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  2. Article: Analysis of allergenic pollen data, focusing on a pollen load threshold statement

    Šukienė, Laura / Šaulienė, Ingrida / Dubakienė, Rūta / Rudzevičienė, Odilija / Daunys, Gintautas

    Aerobiologia. 2021 Dec., v. 37, no. 4

    2021  

    Abstract: Airborne allergenic pollen affects a significant part of the population and the information on pollen load is a valuable tool for public health prevention. The messages should be provided in a form easily understandable for the population. The study ... ...

    Abstract Airborne allergenic pollen affects a significant part of the population and the information on pollen load is a valuable tool for public health prevention. The messages should be provided in a form easily understandable for the population. The study provides new insight for the categorisation of pollen load by defining thresholds solely from aerobiological data. Using the long-term airborne pollen data of Corylus, Alnus, Betula, Poaceae, and Artemisia have been evaluated the regionality of pollen concentrations in Lithuania. SPIn and peak values of the main pollen season highlighted as regionality indicators. The largest differences between stations were found in the cases of Corylus and Artemisia.The principle enabling a group of pollen concentrations into levels has been analysed based on retrospective aerobiological data of five pollen types. Thresholds were determined by employing the lowest peak value of the pollen season and applying the 25% principle for selected pollen types. The results were verified by performing associations of defined thresholds with retrospective morbidity data of allergic rhinitis and allergic asthma in Lithuania. Determined pollen thresholds can be used in epidemiological studies requiring associations with pollen concentration. Thresholds could also complement air quality information by integrating pollen load data into public messages or contribute to the development of mHealth systems.
    Keywords Alnus ; Artemisia ; Betula ; Corylus ; Poaceae ; air quality ; allergenicity ; allergic rhinitis ; asthma ; morbidity ; pollen ; pollen loads ; pollen season ; public health ; telemedicine ; Lithuania
    Language English
    Dates of publication 2021-12
    Size p. 843-860.
    Publishing place Springer Netherlands
    Document type Article
    ZDB-ID 1499126-3
    ISSN 1573-3025 ; 0393-5965
    ISSN (online) 1573-3025
    ISSN 0393-5965
    DOI 10.1007/s10453-021-09727-2
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  3. Article ; Online: Clustering approach for the analysis of the fluorescent bioaerosol collected by an automatic detector.

    Daunys, Gintautas / Šukienė, Laura / Vaitkevičius, Lukas / Valiulis, Gediminas / Sofiev, Mikhail / Šaulienė, Ingrida

    PloS one

    2021  Volume 16, Issue 3, Page(s) e0247284

    Abstract: Automatically operating particle detection devices generate valuable data, but their use in routine aerobiology needs to be harmonized. The growing network of researchers using automatic pollen detectors has the challenge to develop new data processing ... ...

    Abstract Automatically operating particle detection devices generate valuable data, but their use in routine aerobiology needs to be harmonized. The growing network of researchers using automatic pollen detectors has the challenge to develop new data processing systems, best suited for identification of pollen or spore from bioaerosol data obtained near-real-time. It is challenging to recognise all the particles in the atmospheric bioaerosol due to their diversity. In this study, we aimed to find the natural groupings of pollen data by using cluster analysis, with the intent to use these groupings for further interpretation of real-time bioaerosol measurements. The scattering and fluorescence data belonging to 29 types of pollen and spores were first acquired in the laboratory using Rapid-E automatic particle detector. Neural networks were used for primary data processing, and the resulting feature vectors were clustered for scattering and fluorescence modality. Scattering clusters results showed that pollen of the same plant taxa associates with the different clusters corresponding to particle shape and size properties. According to fluorescence clusters, pollen grouping highlighted the possibility to differentiate Dactylis and Secale genera in the Poaceae family. Fluorescent clusters played a more important role than scattering for separating unidentified fluorescent particles from tested pollen. The proposed clustering method aids in reducing the number of false-positive errors.
    MeSH term(s) Aerosols/analysis ; Aerosols/chemistry ; Cluster Analysis ; Environmental Monitoring/methods ; Fluorescence ; Models, Theoretical ; Pollen/chemistry ; Spectrometry, Fluorescence/methods ; Spores/isolation & purification
    Chemical Substances Aerosols
    Language English
    Publishing date 2021-03-11
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ISSN 1932-6203
    ISSN (online) 1932-6203
    DOI 10.1371/journal.pone.0247284
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  4. Article: Detection and Microscopy of <i>Alnus glutinosa</i> Pollen Fluorescence Peculiarities

    Šaulienė, Ingrida / Šukienė, Laura / Daunys, Gintautas / Valiulis, Gediminas / Lankauskas, Alfredas / Kokina, Inese / Gerbreders, Vjačeslavs / Gavarāne, Inese

    Forests. 2019 Oct. 28, v. 10, no. 11

    2019  

    Abstract: Alnus glutinosa is an important woody plant in Lithuanian forest ecosystems. Knowledge of fluorescence properties of black alder pollen is necessary for scientific and practical purposes. By the results of the study, we aimed to evaluate possibilities of ...

    Abstract Alnus glutinosa is an important woody plant in Lithuanian forest ecosystems. Knowledge of fluorescence properties of black alder pollen is necessary for scientific and practical purposes. By the results of the study, we aimed to evaluate possibilities of identifying Alnus glutinosa pollen fluorescence properties by modeling ozone effect and applying two different fluorescence-based devices. To implement the experiments, black alder pollen was collected in a typical habitat during the annual flowering period in 2018–2019. There were three groups of experimental variants, which differed in the duration of exposure to ozone, conditions of pollen storage before the start of the experiment, and the exposure time. Data for pollen fluorescence analysis were collected using two methods. The microscopy method was used in order to evaluate the possibility of employing image analysis systems for investigation of pollen fluorescence. The second data collection method is related to an automatic device identifying pollen in real time, which uses the fluorescence method in the pollen recognition process. Data were assessed employing image analysis and principal component analysis (PCA) methods. Digital images of ozone-exposed pollen observed under the fluorescence microscope showed the change of the dominant green colour toward the blue spectrum. Meanwhile, the automatic detector detects more pollen whose fluorescence is at the blue light spectrum. It must be noted that assessing pollen fluorescence several months after exposure to ozone, no effect of ozone on fluorescence remains.
    Keywords Alnus glutinosa ; blue light ; color ; data collection ; digital images ; exposure duration ; flowering ; fluorescence ; fluorescence microscopes ; fluorescence microscopy ; forest ecosystems ; habitats ; image analysis ; models ; ozone ; pollen ; principal component analysis ; woody plants
    Language English
    Dates of publication 2019-1028
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2527081-3
    ISSN 1999-4907
    ISSN 1999-4907
    DOI 10.3390/f10110959
    Database NAL-Catalogue (AGRICOLA)

    More links

    Kategorien

  5. Article: Effect of title on eye-movement exploration of cubist paintings by Fernand Léger.

    Kapoula, Zoi / Daunys, Gintautas / Herbez, Olivier / Yang, Qing

    Perception

    2009  Volume 38, Issue 4, Page(s) 479–491

    Abstract: Franklin et al (1993, Leonardo 26 103-108) reported that title information influenced the interpretation of paintings but not the way observers explore and look at the paintings; in their study subjects used a hand pointer to indicate where they looked. ... ...

    Abstract Franklin et al (1993, Leonardo 26 103-108) reported that title information influenced the interpretation of paintings but not the way observers explore and look at the paintings; in their study subjects used a hand pointer to indicate where they looked. We used eye-movement recording and examined the effect of title on eye-movement exploration of nonrealistic cubist paintings giving rise to free interpretation. Three paintings by Fernand Léger were used: The Wedding contained high density of small fragments of real human faces, limbs, or arbitrary fragments mixed with large plane surfaces; The Alarm Clock consisted of arbitrary fragments creating perception of a person; Contrast of Forms contained forms and cylinders. Different groups of naive subjects explored paintings without knowing the title (spontaneous condition), with the instruction to invent a title (active condition), and after announcement of the authentic title (driven condition). Exploration time was unrestricted and eye movements were recorded by Chronos video-oculography. Fixation duration was found to increase in the driven condition relative to active condition; such increase occurred for all paintings. In contrast, fixation-duration variability remained stable over all title conditions. Saccade amplitude increased in the driven condition for Contrast of Forms. Increase of fixation duration and of saccade size are attributed to additional cognitive analysis, ie search fitting between the title and the painting. When comparing paintings within each title condition, The Wedding produced different results than the other paintings: longer exploration time (in spontaneous condition), higher fixation duration variability (in spontaneous and driven conditions), but smaller saccade sizes (in active and driven conditions). The differences are attributed to visual aspects (high density of small fragments) but also to complex semantic analysis of multiple segments of faces and limbs contained by this painting. Spatial distribution of fixation time was highly selective, with a preponderance of the central area that was the most fixated for all paintings and all title conditions. In the driven condition, however, loci of most frequent fixations were different than in the other conditions from the first 5 s; particularly for The Alarm Clock the title drove the eyes rapidly on the inconspicuous fragment of the clock. Our findings go against Franklin's conclusions. We conclude that title information influences both physiological parameters of eye movements and the distribution of fixation time over different selected areas of the painting.
    MeSH term(s) Adult ; Eye Movement Measurements/statistics & numerical data ; Eye Movements/physiology ; Female ; Fixation, Ocular/physiology ; Humans ; Male ; Middle Aged ; Paintings/psychology ; Pattern Recognition, Visual/physiology ; Saccades/physiology ; Terminology as Topic ; Time Factors ; Young Adult
    Language English
    Publishing date 2009
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 185533-5
    ISSN 1468-4233 ; 0301-0066
    ISSN (online) 1468-4233
    ISSN 0301-0066
    DOI 10.1068/p6080
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  6. Article: Divergence influences triggering of both vertical and horizontal saccades.

    Vernet, Marine / Yang, Qing / Daunys, Gintautas / Orssaud, Christophe / Kapoula, Zoï

    Optometry and vision science : official publication of the American Academy of Optometry

    2008  Volume 85, Issue 3, Page(s) 187–195

    Abstract: Purpose: In real life, divergence is frequently combined with vertical saccades. The purpose of this study was to examine the initiation of vertical and horizontal saccades, pure or combined with divergence.: Methods: We used a gap paradigm to elicit ...

    Abstract Purpose: In real life, divergence is frequently combined with vertical saccades. The purpose of this study was to examine the initiation of vertical and horizontal saccades, pure or combined with divergence.
    Methods: We used a gap paradigm to elicit vertical or horizontal saccades (10 degrees), pure or combined with a predictable divergence (10 degrees). Eye movements from 12 subjects were recorded with EyeLink II.
    Results: The major results were (i) when combined with divergence, the latency of horizontal saccades increased but not the latency of vertical saccades; (ii) for both vertical and horizontal saccades, a tight correlation between the latency of saccade and divergence was found; (iii) when the divergence was anticipated, the saccade was delayed.
    Conclusion: We conclude that the initiation of both components of combined movements is interdependent.
    MeSH term(s) Adult ; Convergence, Ocular/physiology ; Female ; Humans ; Male ; Middle Aged ; Saccades/physiology ; Vision, Binocular/physiology
    Language English
    Publishing date 2008-03
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 1001706-9
    ISSN 1538-9235 ; 1040-5488
    ISSN (online) 1538-9235
    ISSN 1040-5488
    DOI 10.1097/OPX.0b013e3181647196
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  7. Article ; Online: TMS of the posterior parietal cortex delays the latency of unpredictable saccades but not when they are combined with predictable divergence.

    Vernet, Marine / Yang, Qing / Daunys, Gintautas / Orssaud, Christophe / Kapoula, Zoï

    Brain research bulletin

    2008  Volume 76, Issue 1-2, Page(s) 50–56

    Abstract: This study tests the influence of transcranial magnetic stimulation (TMS) of the posterior parietal cortex (PPC) on the initiation of horizontal and vertical saccades, alone or combined with a predictable divergence. A gap paradigm was used; TMS was ... ...

    Abstract This study tests the influence of transcranial magnetic stimulation (TMS) of the posterior parietal cortex (PPC) on the initiation of horizontal and vertical saccades, alone or combined with a predictable divergence. A gap paradigm was used; TMS was applied 100 ms after target onset. TMS of the left PPC increased the latency of unpredictable rightward saccades, while TMS of the right PPC increased the latency of unpredictable downward saccades. Yet, when unpredictable saccades were combined with predictable divergence, neither component was affected. We suggest that in the latter case, the initiation of both components was taken in charge by another area, e.g. frontal. Thus, even when one component was predictable, a common mechanism controls the initiation of both components. The results confirm that TMS only modifies the latency when the cortical area stimulated is involved in the triggering of the eye movement.
    MeSH term(s) Adult ; Humans ; Middle Aged ; Parietal Lobe/anatomy & histology ; Parietal Lobe/physiology ; Psychomotor Performance ; Reaction Time/physiology ; Saccades/physiology ; Transcranial Magnetic Stimulation
    Language English
    Publishing date 2008-05-15
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 197620-5
    ISSN 1873-2747 ; 0361-9230
    ISSN (online) 1873-2747
    ISSN 0361-9230
    DOI 10.1016/j.brainresbull.2007.11.007
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  8. Book ; Online: Automatic pollen recognition with the Rapid-E particle counter

    Šaulienė, Ingrida / Šukienė, Laura / Daunys, Gintautas / Valiulis, Gediminas / Vaitkevičius, Lukas / Matavulj, Predrag / Brdar, Sanja / Panic, Marko / Sikoparija, Branko / Clot, Bernard / Crouzy, Benoît / Sofiev, Mikhail

    eISSN: 1867-8548

    the first-level procedure, experience and next steps

    2019  

    Abstract: Pollen-induced allergies are among the most prevalent non-contagious diseases, with about a quarter of the European population being sensitive to various atmospheric bioaerosols. In most European countries, pollen information is based on a weekly-cycle ... ...

    Abstract Pollen-induced allergies are among the most prevalent non-contagious diseases, with about a quarter of the European population being sensitive to various atmospheric bioaerosols. In most European countries, pollen information is based on a weekly-cycle Hirst-type pollen trap method. This method is labour-intensive and requires narrow specialized abilities and substantial time, so that the pollen data are always delayed and subject to sampling- and counting-related uncertainties. Emerging new approaches to automatic pollen monitoring can, in principle, allow for real-time availability of the data with no human involvement. The goal of the current paper is to evaluate the capabilities of the new Plair Rapid-E pollen monitor and to construct a first-level pollen recognition algorithm. The evaluation was performed for three devices located in Lithuania, Serbia and Switzerland, with independent calibration data and classification algorithms. The Rapid-E output data include multi-angle scattering images and the fluorescence spectra recorded at several times for each particle reaching the device. Both modalities of the Rapid-E output were treated with artificial neural networks (ANNs) and the results were combined to obtain the pollen type. For the first classification experiment, the monitor was challenged with a large variety of pollen types and the quality of many-to-many classification was evaluated. It was shown that in this case, both scattering- and fluorescence-based recognition algorithms fall short of acceptable quality. The combinations of these algorithms performed better, exceeding 80 % accuracy for 5 out of 11 species. Fluorescence spectra showed similarities among different species, ending up with three well-resolved groups: ( Alnus , Corylus , Betula and Quercus ), ( Salix and Populus ) and ( Festuca , Artemisia and Juniperus ). Within these groups, pollen is practically indistinguishable for the first-level recognition procedure. Construction of multistep algorithms with sequential discrimination of pollen inside each group seems to be one of the possible ways forward. In order to connect the classification experiment to existing technology, a short comparison with the Hirst measurements is presented and the issue of false positive pollen detections by Rapid-E is discussed.
    Subject code 333
    Language English
    Publishing date 2019-06-28
    Publishing country de
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

    More links

    Kategorien

  9. Article: Gap effects on saccade and vergence latency.

    Coubard, Olivier / Daunys, Gintautas / Kapoula, Zoï

    Experimental brain research

    2004  Volume 154, Issue 3, Page(s) 368–381

    Abstract: To explore visual space, we make saccades, vergence, and, most frequently, combined saccade-vergence eye movements. The initiation of saccades is well studied, while that of vergence is less explored. Saccade latency is influenced by the fixation task: ... ...

    Abstract To explore visual space, we make saccades, vergence, and, most frequently, combined saccade-vergence eye movements. The initiation of saccades is well studied, while that of vergence is less explored. Saccade latency is influenced by the fixation task: when the target appears simultaneously with the offset of the fixation point, latencies tend to be regular, whereas the introduction of a gap period before target onset causes the emergence of express latencies (80- to 120-ms). This study examines in ten normal adults whether the gap paradigm has a similar effect on the latency of vergence and combined eye movements. The second goal is to identify contextual factors that favor the emergence of short latencies, by comparing a condition in which gap and simultaneous trials were performed in separate blocks (pure blocks) with a condition in which the two types of trials were interleaved randomly (mixed blocks). The results are: (1) the gap paradigm reduced similarly (by approximately -30 ms) the mean latency of saccades, convergence, divergence, and both the saccadic and vergence components of combined eye movements; (2) the gap paradigm was responsible for the emergence of 80- to 120-ms latencies for saccades and divergence (pure or combined), but rarely for convergence; (3) inspection of the latency distributions showed that such short latencies formed a clearly distinct population, different from anticipatory responses or regular latencies, for saccades (pure or combined) but not for pure vergence; importantly, distinct express latencies were found also for the convergence and divergence components of combined eye movements; (4) no difference was found for the group of subjects between pure and mixed blocks, but the latter yielded shorter latencies for some subjects, suggesting an idiosyncratic phenomenon. We suggest that distinct express latencies are specific to saccades and could correspond to a specific mode of saccade initiation. Interestingly, the express mode of triggering can be transferred to the vergence component in the ecological condition in which saccade is combined with vergence.
    MeSH term(s) Adolescent ; Adult ; Brain/physiology ; Convergence, Ocular/physiology ; Female ; Fixation, Ocular/physiology ; Humans ; Male ; Middle Aged ; Models, Neurological ; Observer Variation ; Photic Stimulation ; Reaction Time/physiology ; Saccades/physiology ; Space Perception/physiology
    Language English
    Publishing date 2004-02
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1201-4
    ISSN 1432-1106 ; 0014-4819
    ISSN (online) 1432-1106
    ISSN 0014-4819
    DOI 10.1007/s00221-003-1670-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

  10. Article: Role of the posterior parietal cortex in the initiation of saccades and vergence: right/left functional asymmetry.

    Kapoula, Zoï / Yang, Qing / Coubard, Olivier / Daunys, Gintautas / Orssaud, Christophe

    Annals of the New York Academy of Sciences

    2005  Volume 1039, Page(s) 184–197

    Abstract: This study explored in humans the role of the posterior parietal cortex (PPC) in saccades, vergence, and combined saccade-vergence movements by means of transcranial magnetic stimulation (TMS). TMS was applied to the right PPC at 80 ms, 90 ms, or 100 ms ... ...

    Abstract This study explored in humans the role of the posterior parietal cortex (PPC) in saccades, vergence, and combined saccade-vergence movements by means of transcranial magnetic stimulation (TMS). TMS was applied to the right PPC at 80 ms, 90 ms, or 100 ms after target onset in experiment 1, and to the left PPC in experiment 2. Control experiments were also run in which TMS was applied over the primary motor cortex at 90 ms after target onset. Relative to no-TMS trials, TMS over the right PPC prolonged significantly the latency of almost all eye movements (saccades in either direction, convergence, divergence, and components of combined eye movements). Such latency increase was significant mostly when TMS was delivered 90 ms after target onset. In contrast, TMS of the left PPC increased the latency only for saccades to right, convergence, and convergence combined with rightward saccades; latency increase occurred for all time windows of TMS deliver (80, 90, or 100 ms after target onset). TMS over the vertex had no effect on the latency for any type of eye movement. TMS of either the left or the right PPC or of the motor cortex did not alter the accuracy of any type of eye movement. Thus, the effects of TMS on latency are time-, area-, and eye-movement-specific. We suggest that the right PPC is involved primarily in the processing of fixation disengagement, whereas the left PPC participates in the initiation of eye movements via different spatial selective mechanisms that concern exclusively targets to the right and/or to near.
    MeSH term(s) Adult ; Eye Movements/physiology ; Female ; Functional Laterality ; Humans ; Male ; Middle Aged ; Oculomotor Nerve/physiology ; Parietal Lobe/physiology ; Parietal Lobe/radiation effects ; Reaction Time ; Reference Values ; Saccades/physiology ; Transcranial Magnetic Stimulation ; Visual Perception/physiology
    Language English
    Publishing date 2005-04
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 211003-9
    ISSN 1749-6632 ; 0077-8923
    ISSN (online) 1749-6632
    ISSN 0077-8923
    DOI 10.1196/annals.1325.018
    Database MEDical Literature Analysis and Retrieval System OnLINE

    More links

    Kategorien

To top