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  1. Article ; Online: The effect of inflorescence display size and flower position on pollination success in two deceptive and one rewarding orchid.

    Lanzino, M / Palermo, A M / Pellegrino, G

    Plant biology (Stuttgart, Germany)

    2023  Volume 25, Issue 3, Page(s) 396–402

    Abstract: Inflorescence display size and flower position on the inflorescence play important roles in plant reproduction, in the formation of fruits and are primarily linked to pollinator behaviour. We used three orchids to determine how visitation rates and ... ...

    Abstract Inflorescence display size and flower position on the inflorescence play important roles in plant reproduction, in the formation of fruits and are primarily linked to pollinator behaviour. We used three orchids to determine how visitation rates and choice of pollinator depend on number and position of the flowers along the inflorescence. We measured reproductive success in (1) natural conditions, (2) hand-pollination experiments and (3) an experimental design, by modifying composition of inflorescences in populations of two deceptive orchids, Orchis anthropophora and O. italica, and one rewarding orchid, Anacamptis coriophora subsp. fragrans. There were no differences in natural fruit production in relation to flower position on the inflorescence (i.e. upper versus lower part), suggesting no preference of pollinators for different parts of the inflorescence. Hand-pollination experiments highlighted low pollen limitation in A. coriophora subsp. fragrans but high limitation in O. italica and O. anthropophora. Reproductive success of deceptive orchids in experimental plots decreased significantly when flowers on the upper half of the inflorescence were removed leading to reduced floral display, while reproductive success of the nectariferous species did not differ significantly. Our data highlight that in the examined orchids there is no clear relationship between fruit formation and flower position along inflorescences. Thus we can affirm that, for orchids, the entire inflorescence plays a dominant role in insect attraction but the part of the flower spike does not influence the choice of the insect. This implies that all flowers have the same possibility of receiving visits from pollinators, and therefore each flower has the same opportunity to set fruit.
    MeSH term(s) Pollination ; Inflorescence ; Flowers ; Reproduction ; Fruit ; Orchidaceae
    Language English
    Publishing date 2023-02-20
    Publishing country England
    Document type Journal Article
    ZDB-ID 1464075-2
    ISSN 1438-8677 ; 1435-8603
    ISSN (online) 1438-8677
    ISSN 1435-8603
    DOI 10.1111/plb.13505
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Threat learning in space: how stimulus-outcome spatial compatibility modulates conditioned skin conductance response.

    Starita, F / Stussi, Y / Garofalo, S / di Pellegrino, G

    International journal of psychophysiology : official journal of the International Organization of Psychophysiology

    2023  Volume 190, Page(s) 30–41

    Abstract: A central question in Pavlovian conditioning concerns the critical conditions that drive the acquisition and maintenance of the stimulus-outcome association. The spatial relationship between the conditioned (CS) and unconditioned (US) stimuli is ... ...

    Abstract A central question in Pavlovian conditioning concerns the critical conditions that drive the acquisition and maintenance of the stimulus-outcome association. The spatial relationship between the conditioned (CS) and unconditioned (US) stimuli is considered to exert strong effects on learning. However, how spatial information modulates Pavlovian learning remains mostly unexplored in humans. Here, we test how the compatibility between the CS and the US location influences the acquisition, extinction, and recovery (following reinstatement) of Pavlovian conditioned threat. Participants (N = 20) completed a differential threat conditioning task in which visual CSs appeared on the same (compatible) or opposite (incompatible) hemispace as the US delivery (aversive shock to one hand), while their skin conductance response served as an index of learning. Results show that initial threat expectations were biased in favor of compatible CSs before conditioning. Nevertheless, this bias was revised during acquisition to reflect current stimulus-outcome contingencies. Computational modeling suggested that this effect occurred through a higher reliance on positive aversive prediction errors for incompatible CSs, thereby facilitating learning of their association with the US. Additionally, the conditioned response to incompatible CSs was associated with initially slower extinction and a greater recovery after threat reinstatement. These findings suggest that spatial information conveyed by stimuli and outcomes can be flexibly used to enact defensive responses to the current source of danger, highlighting the adaptive nature of Pavlovian learning.
    MeSH term(s) Humans ; Fear/physiology ; Extinction, Psychological/physiology ; Learning ; Conditioning, Classical/physiology ; Affect
    Language English
    Publishing date 2023-06-07
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 605645-3
    ISSN 1872-7697 ; 0167-8760
    ISSN (online) 1872-7697
    ISSN 0167-8760
    DOI 10.1016/j.ijpsycho.2023.06.003
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: 40 Hz Repetitive auditory stimulation promotes corticospinal plasticity.

    Pinardi, Mattia / Schuler, Anna-Lisa / Di Pino, Giovanni / Pellegrino, Giovanni

    Clinical neurophysiology : official journal of the International Federation of Clinical Neurophysiology

    2024  Volume 162, Page(s) 79–81

    Language English
    Publishing date 2024-03-22
    Publishing country Netherlands
    Document type Letter
    ZDB-ID 1463630-x
    ISSN 1872-8952 ; 0921-884X ; 1388-2457
    ISSN (online) 1872-8952
    ISSN 0921-884X ; 1388-2457
    DOI 10.1016/j.clinph.2024.03.018
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article: Pollination mechanism in

    Lanzino, Micaela / Palermo, Anna Maria / Pellegrino, Giuseppe

    AoB PLANTS

    2023  Volume 15, Issue 5, Page(s) plad054

    Abstract: Orchidaceae, one of the most numerous families in the world's flora, have evolved various pollination strategies to favour cross-pollination, such as deceptive pollination and pollinarium reconfiguration. Among the terrestrial orchids of the ... ...

    Abstract Orchidaceae, one of the most numerous families in the world's flora, have evolved various pollination strategies to favour cross-pollination, such as deceptive pollination and pollinarium reconfiguration. Among the terrestrial orchids of the Mediterranean, only species belonging to the genus
    Language English
    Publishing date 2023-08-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 2555823-7
    ISSN 2041-2851
    ISSN 2041-2851
    DOI 10.1093/aobpla/plad054
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Vitamin D intoxication: myth or reality.

    Pellegrino, Giuseppe / Ascenti, Velio / Desiderio, Elio / Carrafiello, Gianpaolo

    Minerva medica

    2023  Volume 114, Issue 5, Page(s) 587–589

    MeSH term(s) Humans ; Vitamin D ; Calcium
    Chemical Substances Vitamin D (1406-16-2) ; Calcium (SY7Q814VUP)
    Language English
    Publishing date 2023-07-18
    Publishing country Italy
    Document type Journal Article
    ZDB-ID 123586-2
    ISSN 1827-1669 ; 0026-4806
    ISSN (online) 1827-1669
    ISSN 0026-4806
    DOI 10.23736/S0026-4806.23.08795-5
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Obesity in medical imaging: pitfalls and challenges.

    Pellegrino, Giuseppe / Triggiani, Sonia / Desiderio, Elio / Carrafiello, Gianpaolo

    Minerva medica

    2023  Volume 115, Issue 1, Page(s) 1–3

    MeSH term(s) Humans ; Obesity/diagnostic imaging ; Magnetic Resonance Imaging
    Language English
    Publishing date 2023-12-21
    Publishing country Italy
    Document type Journal Article
    ZDB-ID 123586-2
    ISSN 1827-1669 ; 0026-4806
    ISSN (online) 1827-1669
    ISSN 0026-4806
    DOI 10.23736/S0026-4806.23.09074-2
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Pollen viability of Euro-Mediterranean orchids under different storage conditions: The possible effects of climate change.

    Pellegrino, G / Mahmoudi, M / Palermo, A M

    Plant biology (Stuttgart, Germany)

    2020  Volume 23, Issue 1, Page(s) 140–147

    Abstract: The future impact of climate change and a warmer world is a matter of great concern. We therefore aimed to evaluate the effects of temperature on pollen viability and fruit set of Mediterranean orchids. The in vitro and controlled pollination experiments ...

    Abstract The future impact of climate change and a warmer world is a matter of great concern. We therefore aimed to evaluate the effects of temperature on pollen viability and fruit set of Mediterranean orchids. The in vitro and controlled pollination experiments were performed to evaluate the ability of pollinia stored at lower and higher temperatures to germinate and produce fruits and seeds containing viable embryos. In all of the examined orchids, pollen stored at -20 °C remained fully viable for up to 3 years, reducing its percentage germination from year 4 onwards. Pollinia stored at higher temperatures had a drastic reduction in vitality after 2 days at 41-44 °C, while pollinia stored at 47-50 °C did not show any pollen tube growth. The different levels of pollen viability duration among the examined orchids can be related to their peculiar reproductive biology and pollination ecology. The germinability of pollinia stored at lower temperatures for long periods suggests that orchid pollinia can be conserved ex situ. In contrast, higher temperatures can have harmful effects on the vitality of pollen and consequently on reproductive success of the plants. To our knowledge, this is the first report demonstrating the effects of global change on orchid pollen, and on pollen ability to tolerate, or not, higher air temperatures. Although vegetative reproduction allows orchids to survive a few consecutive warm years, higher temperatures for several consecutive years can have dramatic effects on reproductive success of orchids.
    MeSH term(s) Climate Change ; Cold Temperature ; Freezing ; Germination ; Hot Temperature ; Orchidaceae/physiology ; Pollen/physiology ; Pollination ; Reproduction
    Language English
    Publishing date 2020-11-04
    Publishing country England
    Document type Journal Article
    ZDB-ID 1464075-2
    ISSN 1438-8677 ; 1435-8603
    ISSN (online) 1438-8677
    ISSN 1435-8603
    DOI 10.1111/plb.13185
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: fMRI Acoustic Noise Enhances Parasympathetic Activity in Humans.

    Schuler, Anna-Lisa / Pellegrino, Giovanni

    Brain sciences

    2021  Volume 11, Issue 11

    Abstract: Background: Functional magnetic resonance imaging (fMRI) is one of the most important neuroimaging techniques; nevertheless, the acoustic noise of the MR scanner is unavoidably linked to the process of data acquisition. We hypothesized that the auditory ...

    Abstract Background: Functional magnetic resonance imaging (fMRI) is one of the most important neuroimaging techniques; nevertheless, the acoustic noise of the MR scanner is unavoidably linked to the process of data acquisition. We hypothesized that the auditory noise of the scanner has an effect on autonomic activity.
    Methods: We measured heart rate variability (HRV) while exposing 30 healthy subjects to fMRI noise. In doing so, we demonstrated an increase in parasympathetic nervous system (PNS) activity compared to silence and white noise and a decrease in sympathetic nervous system (SNS) activity compared to white noise.
    Conclusions: The influence of MR scanner noise on the autonomic nervous system should be taken into account when performing fMRI experiments.
    Language English
    Publishing date 2021-10-27
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2651993-8
    ISSN 2076-3425
    ISSN 2076-3425
    DOI 10.3390/brainsci11111416
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  9. Article ; Online: Sympatric reinforcement of reproductive barriers between Neotinea tridentata and N. ustulata (Orchidaceae).

    Pellegrino, Giuseppe

    Journal of plant research

    2016  Volume 129, Issue 6, Page(s) 1061–1068

    Abstract: Reinforcement is the process by which selection favors traits that decrease mating between two incipient species in response to costly mating or the production of maladapted hybrids, causing the evolution of greater reproductive isolation between ... ...

    Abstract Reinforcement is the process by which selection favors traits that decrease mating between two incipient species in response to costly mating or the production of maladapted hybrids, causing the evolution of greater reproductive isolation between emerging species. I have studied a pair of orchids, Neotinea tridentata and N. ustulata, to examine the level of postmating pre- and post-zygotic isolating mechanisms that maintain these species, and the degree to which the boundary may still be permeable to gene flow. In this study, I performed pollen tube growth rate experiments and I investigated pre- and post-zygotic barriers by performing hand pollination experiments in order to evaluate fruit set, embryonate seed set and seed germination rates by intra- and interspecific crosses. Fruit set, the percentage of embryonate seeds and germinability of interspecific crosses were reduced compared to intraspecific pollinations, showing significant differences between sympatric and allopatric populations. While in allopatric populations the post-pollination isolation index ranged between 0.40 and 0.11, in sympatric populations orchid pairs showed total isolation due to post-pollination prezygotic barriers, guaranteed at the level of pollen-stigma interactions. Indeed, in sympatric populations, pollen tubes reached the ovary after 24 h in only 8 out of 45 plants; in the remaining cases, the pollen tubes did not enter the ovary, and thus no fruit set occurred. This pair of orchids is characterized by postmating pre-zygotic reproductive isolation in sympatric populations that prevents the formation of hybrids. This mechanism of speciation, starting in allopatry and triggering the reinforcement mechanisms of reproductive isolation in secondary sympatry, is the most likely explanation for the pattern of evolutionary transitions found in this pair of orchids.
    Language English
    Publishing date 2016-11
    Publishing country Japan
    Document type Journal Article
    ZDB-ID 2077362-6
    ISSN 1618-0860 ; 0918-9440
    ISSN (online) 1618-0860
    ISSN 0918-9440
    DOI 10.1007/s10265-016-0855-7
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: In silico

    Laranjeira, S / Pellegrino, G / Bhangra, K S / Phillips, J B / Shipley, R J

    Journal of the Royal Society, Interface

    2022  Volume 19, Issue 188, Page(s) 20210824

    Abstract: Peripheral nerve injuries affect millions of people per year and cause loss of sensation and muscle control alongside chronic pain. The most severe injuries are treated through a nerve autograft; however, donor site morbidity and poor outcomes mean ... ...

    Abstract Peripheral nerve injuries affect millions of people per year and cause loss of sensation and muscle control alongside chronic pain. The most severe injuries are treated through a nerve autograft; however, donor site morbidity and poor outcomes mean alternatives are required. One option is to engineer nerve replacement tissues to provide a supportive microenvironment to encourage nerve regeneration as an alternative to nerve grafts. Currently, progress is hampered due to a lack of consensus on how to arrange materials and cells in space to maximize rate of regeneration. This is compounded by a reliance on experimental testing, which precludes extensive investigations of multiple parameters due to time and cost limitations. Here, a computational framework is proposed to simulate the growth of repairing neurites, captured using a random walk approach and parameterized against literature data. The framework is applied to a specific scenario where the engineered tissue comprises a collagen hydrogel with embedded biomaterial fibres. The size and number of fibres are optimized to maximize neurite regrowth, and the robustness of model predictions is tested through sensitivity analyses. The approach provides an
    MeSH term(s) Biocompatible Materials ; Collagen ; Humans ; Nerve Regeneration/physiology ; Peripheral Nerve Injuries/surgery ; Tissue Engineering
    Chemical Substances Biocompatible Materials ; Collagen (9007-34-5)
    Language English
    Publishing date 2022-03-02
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2156283-0
    ISSN 1742-5662 ; 1742-5689
    ISSN (online) 1742-5662
    ISSN 1742-5689
    DOI 10.1098/rsif.2021.0824
    Database MEDical Literature Analysis and Retrieval System OnLINE

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