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1.
Chem Biodivers ; : e202400523, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38814629

ABSTRACT

Cold-pressed Camelina oil is a traditional oil registered as a traditional food in Poland. Camelina oil has health-promoting properties and high oxidative stability. This may be due to the presence of various bioactive antioxidant compounds such as carotenoids, sterols and polyphenols. Bioactive compounds content in Camelina oil depends mainly on the varieties and on the conditions under which the crop was grown therefore the aim of the research was to analyse antioxidant bioactive compounds in oil from different cultivars of Camelina sativa seeds and to determine their relationship with oil parameters.

2.
IEEE Trans Robot ; 40: 2166-2180, 2024.
Article in English | MEDLINE | ID: mdl-38799790

ABSTRACT

A new subclass of soft robot, known as tip-extending or "vine" robots, consists of long inflatable devices that move through the environment by extending from the tip. A key requirement for many applications of these robots is a working channel-a hollow tube through the core of the robot for passing tools, sensors, fluids, etc. While working channels have been proposed in a few vine robots, it remains an open challenge to create miniaturized vine robots (diameter < 1 cm) with working channels that enable continuous access through the core. In this paper, we analyze the growth models of current vine robot designs and show that the working channel greatly increases required pressure to grow at small scales due to internal friction. Based on this insight, we propose the concept of storing scrunched material at the tip of the vine robot to circumvent this frictional force. We validate our models and demonstrate this concept via prototypes down to diameters of 2.3 mm. Overall, this work enables the creation of miniaturized vine robots with working channels, which significantly enhances their practicality and potential for impact in applications such as minimally invasive surgery.

3.
Sci Adv ; 9(15): eade4083, 2023 04 14.
Article in English | MEDLINE | ID: mdl-37043570

ABSTRACT

In language, grammatical dependencies often hold between items that are not immediately adjacent to each other. Acquiring these nonadjacent dependencies is crucial for learning grammar. However, there are potentially infinitely many dependencies in the language input. How does the infant brain solve this computational learning problem? Here, we demonstrate that while rudimentary sensitivity to nonadjacent regularities may be present relatively early, robust and reliable learning can only be achieved when convergent statistical and perceptual, specifically prosodic cues, are both present, helping the infant brain detect the building blocks that form a nonadjacent dependency. This study contributes to our understanding of the neural foundations of rule learning that pave the way for language acquisition.


Subject(s)
Cues , Learning , Humans , Infant , Language Development , Language , Linguistics
4.
Dev Sci ; 26(2): e13304, 2023 03.
Article in English | MEDLINE | ID: mdl-35841609

ABSTRACT

Prosody is the fundamental organizing principle of spoken language, carrying lexical, morphosyntactic, and pragmatic information. It, therefore, provides highly relevant input for language development. Are infants sensitive to this important aspect of spoken language early on? In this study, we asked whether infants are able to discriminate well-formed utterance-level prosodic contours from ill-formed, backward prosodic contours at birth. This deviant prosodic contour was obtained by time-reversing the original one, and super-imposing it on the otherwise intact segmental information. The resulting backward prosodic contour was thus unfamiliar to the infants and ill-formed in French. We used near-infrared spectroscopy (NIRS) in 1-3-day-old French newborns (n = 25) to measure their brain responses to well-formed contours as standards and their backward prosody counterparts as deviants in the frontal, temporal, and parietal areas bilaterally. A cluster-based permutation test revealed greater responses to the Deviant than to the Standard condition in right temporal areas. These results suggest that newborns are already capable of detecting utterance-level prosodic violations at birth, a key ability for breaking into the native language, and that this ability is supported by brain areas similar to those in adults. RESEARCH HIGHLIGHTS: At birth, infants have sophisticated speech perception abilities. Prosody may be particularly important for early language development. We show that newborns are already capable of discriminating utterance-level prosodic contours. This discrimination can be localized to the right hemisphere of the neonate brain.


Subject(s)
Language Development , Speech Perception , Infant , Adult , Humans , Infant, Newborn , Brain/physiology , Language , Speech Perception/physiology , Brain Mapping
5.
Infancy ; 27(5): 963-971, 2022 09.
Article in English | MEDLINE | ID: mdl-35833310

ABSTRACT

Infants start tracking auditory-only non-adjacent dependencies (NAD) between 15 and 18 months of age. Given that audiovisual speech, normally available in a talker's mouth, is perceptually more salient than auditory speech and that it facilitates speech processing and language acquisition, we investigated whether 15-month-old infants' NAD learning is modulated by attention to a talker's mouth. Infants performed an audiovisual NAD learning task while we recorded their selective attention to the eyes, mouth, and face of an actress while she spoke an artificial language that followed an AXB structure (tis-X-bun; nal-X-gor) during familiarization. At test, the actress spoke the same language (grammatical trials; tis-X-bun; nal-X-gor) or a novel one that violated the AXB structure (ungrammatical trials; tis-X-gor; nal-X-bun). Overall, total duration of looking did not differ during the familiar and novel test trials but the time-course of selective attention to the talker's face and mouth revealed that the novel trials maintained infants' attention to the face more than did the familiar trials. Crucially, attention to the mouth increased during the novel test trials while it did not change during the familiar test trials. These results indicate that the multisensory redundancy of audiovisual speech facilitates infants' discrimination of non-adjacent dependencies.


Subject(s)
Language Development , Speech Perception , Female , Humans , Infant , Language , Speech
6.
J Exp Child Psychol ; 206: 105070, 2021 06.
Article in English | MEDLINE | ID: mdl-33601290

ABSTRACT

Temporal expectations critically influence perception and action. Previous research reports contradictory results in children's ability to endogenously orient attention in time as well as the developmental course. To reconcile this seemingly conflicting evidence, we put forward the hypothesis that expectancy violations-through the use of invalid trials-are the source of the mixed evidence reported in the literature. With the aim of offering new results that could reconcile previous findings, we tested a group of young children (4- to 7-year-olds), an older group (8- to 12-year-olds), and a group of adults. Temporal cues provided expectations about target onset time, and invalid trials were used such that the target appeared at the unexpected time in 25% of the trials. In both experiments, the younger children responded faster in valid trials than in invalid trials, showing that they benefited from the temporal cue. These results show that young children rely on temporal expectations to orient attention in time endogenously. Importantly, younger children exhibited greater validity effects than older children and adults, and these effects correlated positively with participants' performance in the invalid (unexpected) trials. We interpret the reduction of validity effects with age as an index of better adaptation to the invalid (unexpected) condition. By using invalid trials and testing three age groups, we demonstrate that previous findings are not inconsistent. Rather, evidence converges when considering the presence of expectancy violations that require executive control mechanisms, which develop progressively during childhood. We propose a distinction between rigid and flexible mechanisms of temporal orienting to accommodate all findings.


Subject(s)
Attention , Cues , Adolescent , Adult , Child , Child, Preschool , Executive Function , Humans , Reaction Time
7.
PLoS Biol ; 18(11): e3000895, 2020 11.
Article in English | MEDLINE | ID: mdl-33137084

ABSTRACT

A crucial aspect when learning a language is discovering the rules that govern how words are combined in order to convey meanings. Because rules are characterized by sequential co-occurrences between elements (e.g., "These cupcakes are unbelievable"), tracking the statistical relationships between these elements is fundamental. However, purely bottom-up statistical learning alone cannot fully account for the ability to create abstract rule representations that can be generalized, a paramount requirement of linguistic rules. Here, we provide evidence that, after the statistical relations between words have been extracted, the engagement of goal-directed attention is key to enable rule generalization. Incidental learning performance during a rule-learning task on an artificial language revealed a progressive shift from statistical learning to goal-directed attention. In addition, and consistent with the recruitment of attention, functional MRI (fMRI) analyses of late learning stages showed left parietal activity within a broad bilateral dorsal frontoparietal network. Critically, repetitive transcranial magnetic stimulation (rTMS) on participants' peak of activation within the left parietal cortex impaired their ability to generalize learned rules to a structurally analogous new language. No stimulation or rTMS on a nonrelevant brain region did not have the same interfering effect on generalization. Performance on an additional attentional task showed that this rTMS on the parietal site hindered participants' ability to integrate "what" (stimulus identity) and "when" (stimulus timing) information about an expected target. The present findings suggest that learning rules from speech is a two-stage process: following statistical learning, goal-directed attention-involving left parietal regions-integrates "what" and "when" stimulus information to facilitate rapid rule generalization.


Subject(s)
Attention/physiology , Learning/physiology , Parietal Lobe/physiology , Adult , Brain/physiology , Brain Mapping/methods , Cognition/physiology , Female , Frontal Lobe/physiology , Functional Laterality/physiology , Humans , Language , Linguistics/methods , Magnetic Resonance Imaging/methods , Male , Photic Stimulation/methods , Reaction Time/physiology , Transcranial Magnetic Stimulation/methods , Young Adult
10.
PLoS One ; 13(1): e0190734, 2018.
Article in English | MEDLINE | ID: mdl-29293669

ABSTRACT

[This corrects the article DOI: 10.1371/journal.pone.0184698.].

11.
PLoS One ; 12(9): e0184698, 2017.
Article in English | MEDLINE | ID: mdl-28886169

ABSTRACT

Anticipating both where and when an object will appear is a critical ability for adaptation. Research in the temporal domain in adults indicate that dissociable mechanisms relate to endogenous attention driven by the properties of the stimulus themselves (e.g. rhythmic, sequential, or trajectory cues) and driven by symbolic cues. In infancy, we know that the capacity to endogenously orient attention progressively develops through infancy. However, the above-mentioned distinction has not yet been explored since previous studies involved stimulus-driven cues. The current study tested 12- and 15-month-olds in an adaptation of the anticipatory eye movement procedure to determine whether infants were able to anticipate a specific location and temporal interval predicted only by symbolic pre-cues. In the absence of stimulus-driven cues, results show that only 15-month-olds could show anticipatory behavior based on the temporal information provided by the symbolic cues. Distinguishing stimulus-driven expectations from those driven by symbolic cues allowed dissecting more clearly the developmental progression of temporal endogenous attention.


Subject(s)
Cues , Analysis of Variance , Attention/physiology , Eye Movements/physiology , Female , Humans , Infant , Male , Reaction Time/physiology , Visual Perception/physiology
12.
Front Psychol ; 7: 44, 2016.
Article in English | MEDLINE | ID: mdl-26869953

ABSTRACT

Language is one of the most fascinating abilities that humans possess. Infants demonstrate an amazing repertoire of linguistic abilities from very early on and reach an adult-like form incredibly fast. However, language is not acquired all at once but in an incremental fashion. In this article we propose that the attentional system may be one of the sources for this developmental trajectory in language acquisition. At birth, infants are endowed with an attentional system fully driven by salient stimuli in their environment, such as prosodic information (e.g., rhythm or pitch). Early stages of language acquisition could benefit from this readily available, stimulus-driven attention to simplify the complex speech input and allow word segmentation. At later stages of development, infants are progressively able to selectively attend to specific elements while disregarding others. This attentional ability could allow them to learn distant non-adjacent rules needed for morphosyntactic acquisition. Because non-adjacent dependencies occur at distant moments in time, learning these dependencies may require correctly orienting attention in the temporal domain. Here, we gather evidence uncovering the intimate relationship between the development of attention and language. We aim to provide a novel approach to human development, bridging together temporal attention and language acquisition.

13.
Liver Transpl ; 21(3): 381-95, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25451888

ABSTRACT

Regulatory T cells (Tregs) play an important role in controlling alloreactivity after solid organ transplantation, but they may also impair antiviral immunity. We hypothesized that the Treg frequency and the Treg phenotype are altered in hepatitis C virus (HCV)-infected recipients of liver transplantation (LT) with possible prognostic implications. Tregs from 141 individuals, including healthy individuals, LT recipients with or without persistent HCV infections, and nontransplant patients with chronic HCV, were studied. A comprehensive phenotypic analysis was performed with multicolor flow cytometry, which included standard Treg markers [CD4(+), CD25(hi), CD127(-), and FoxP3(+) in addition to HLA DR, CCR7, CD45RA, CD62L, CD49d, CD39, ICOS and LAP-TGFß stainings. Healthy individuals and LT patients displayed similar Treg frequencies and largely comparable Treg phenotypes, which were stable over time after transplantation. In contrast, Tregs with a CD45RA(-) CCR7(-) effector phenotype were enriched in LT recipients with chronic HCV versus HCV-negative transplant patients. HCV infection, rather than LT, altered the expression of functional markers on Tregs. A principal component analysis revealed distinct Treg phenotypes in HCV-infected LT recipients with rejection and patients with recurrent graft HCV. In conclusion, Treg phenotypes are altered in HCV-infected LT patients. An investigation of Tregs may possibly help to distinguish recurrent HCV from graft rejection. Further functional studies are needed to define the role of Tregs in determining the balance between antiviral and allogenic immunity.


Subject(s)
Immunophenotyping , Liver Failure/surgery , Liver Transplantation , T-Lymphocytes, Regulatory/immunology , Adolescent , Adult , Aged , Biomarkers/metabolism , Case-Control Studies , Female , Flow Cytometry , Graft Rejection/immunology , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/immunology , Humans , Immunophenotyping/methods , Liver Failure/diagnosis , Liver Failure/immunology , Liver Failure/virology , Liver Transplantation/adverse effects , Male , Middle Aged , Phenotype , Principal Component Analysis , Recurrence , T-Lymphocytes, Regulatory/metabolism , Treatment Outcome , Young Adult
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