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The Mexican tetra Astyanax mexicanus presents two contrasting morphs, a widely distributed surface morph and a cave-adapted morph. These cave-adapted morphs have evolved independently from two different lineages (i.e. ‘old’ and ‘new’ lineages); therefore, this model system gives a unique opportunity to explore parallel adaptive evolution in biological traits. The present study corresponds to the first morphological description of the Astyanax mexicanus maturation process of the spermatozoa and oocytes, using thermal and hormonal stimuli to promote spermatogenesis and oogenesis, considering surface and cave morphs from both lineages. We corroborate the relevance of thermal and hormonal stimuli to promote gamete maturation. The hormone Ovaprim (GnRHa + Domperidone) is an effective promoter of ovarian development, maturation end in oocytes and spawning in Astyanax mexicanus. The sperm morphology of Astyanax mexicanus includes the sperm head, the midpiece, and tail or flagellum. We found differences in the spermatozoan total length between environments (F = 9.929, P = 0.05) and linages (F = 49.86, P = 0.005). The oocytes showed a spherical conformation with a mean diameter of 822.4 ± 194.1 μm for the surface populations, and 604.6 ± 38.3 µm for the cave populations. The oocyte chorion presents ridges and grooves that are arranged radially towards the micropyle. A plug in the micropyle zone was observed after fertilization, confirmed by the outer membrane of the chorion, which provides some weak adhesiveness to the substrate. We observed differences in chorion thickness between the contrasting environmental conditions. This is the first morphological characterization of the Sótanos Vázquez, Escondido and Tigre, which previous to this study were only known from speleological expeditions, with no previous biological information available.
Mesozoic ferns from Mexico have been the subject of serious academic endeavours since the beginning of the 20th Century, to understand these plants at the time of their peak diversity. Most findings have been made in a set of Middle Jurassic Basins of the Mixtec Terrain in the Oaxaca State. However, fossil ferns are scarce in other assemblages, so further identification of this group has been infrequent. Here we describe six new and recently collected fossil plants from the Middle Jurassic Otlaltepec Formation, Puebla. Based on their fertile and vegetative fronds, we propose the new genus Paralophosoria Morales-Toledo, Mendoza-Ruiz & Cevallos-Ferriz, gen. nov. in the Dicksoniaceae, represented by Paralophosoria jurassica, Morales-Toledo, Mendoza-Ruiz & Cevallos-Ferriz, sp. nov., and identify the following genera: cf. Aspidistes, Sphenopteris, Spiropteris. A fern with uncertain affinities was also described. This work contributes to the understanding of fern diversity in low latitudes during the Middle Jurassic in Mexico.
An annotated checklist of the helminth parasites associated with reptiles from Peru is provided, as the result of a compilation of parasitological papers published between 1963 and January 2022 and records of species deposited in national and international collections. The list provides data on hosts, developmental stage, sites of infection, geographical distribution in Peruvian territory, code of material deposited in helminthological collections, references and taxonomic notes. The database includes records of 106 different species of helminth parasites (82 nominal species and 24 taxa identified at the generic level), the majority in the adult stage. These helminth parasites come from 18 of the 25 official Peruvian regions. Nematodes have the highest richness in number of species (79 species), followed by trematodes (17 species) and cestodes (nine species). The acanthocephalans are represented by only one species. The parasites with the highest number of records were Physaloptera retusa Rudolphi, 1819 (11 hosts), Physalopteroides venancioi (Lent, Freitas & Proença, 1946) (nine hosts), Strongyluris oscari Travassos, 1923 (seven hosts), and Parapharyngodon scleratus Travassos, 1923 (five hosts), all of which are nematodes. The 106 taxa of helminth parasites have been reported infecting 55 species of reptiles in Peru, distributed in 34 genera and 14 families. The reptile species harbouring the highest number of helminth parasites are the yellow-footed tortoise Chelonoidis denticulatus (Linnaeus) with 18 species (three trematodes and 15 nematodes), followed by the Peru desert tegu Dicrodon guttulatum Duméril & Bibron (Teiidae) with 11 species (three cestodes and eight nematodes) and the yellow-spotted Amazon River turtle Podocnemis unifilis Troschel (Podocnemididae) with 10 species (five trematodes and five nematodes). Of the 524 species of reptiles reported in Peru, only 55 (>10%) are reported as hosts of helminths representing a small proportion considering the great variety of reptile hosts that inhabit the various tropical and subtropical geographical areas of Peru.
Contemporary theories of early development and emerging child psychopathology all posit a major, if not central role for physiological responsiveness. To understand infants’ potential risk for emergent psychopathology, consideration is needed to both autonomic reactivity and environmental contexts (e.g., parent–child interactions). The current study maps infants’ arousal during the face-to-face still-face paradigm using skin conductance (n = 255 ethnically-diverse mother–infant dyads; 52.5% girls, mean infant age = 7.4 months; SD = 0.9 months). A novel statistical approach was designed to model the potential build-up of nonlinear counter electromotive force over the course of the task. Results showed a significant increase in infants’ skin conductance between the Baseline Free-play and the Still-Face phase, and a significant decrease in skin conductance during the Reunion Play when compared to the Still-Face phase. Skin conductance during the Reunion Play phase remained significantly higher than during the Baseline Play phase; indicating that infants had not fully recovered from the mild social stressor. These results further our understanding of infant arousal during dyadic interactions, and the role of caregivers in the development of emotion regulation during infancy.
We extend the classical notion of standardly stratified k-algebra (stated for finite dimensional k-algebras) to the more general class of rings, possibly without 1, with enough idempotents. We show that many of the fundamental results, which are known for classical standardly stratified algebras, can be generalized to this context. Furthermore, new classes of rings appear as: ideally standardly stratified and ideally quasi-hereditary. In the classical theory, it is known that quasi-hereditary and ideally quasi-hereditary algebras are equivalent notions, but in our general setting, this is no longer true. To develop the theory, we use the well-known connection between rings with enough idempotents and skeletally small categories (ringoids or rings with several objects).
Patient's outgroup socialization may be a problem in the psychotherapeutic group functioning. Disadvantages – and even benefits – of this common issue in psychotherapy have been described (Vinogradov S., Yalom I.). However, the impact of new social networks – that facilitate other ways of immediate and easy communication – on this phenomenon is still unknown.
Aims and objectives
To explore the risks of spontaneous “self-help groups” supported by new technologies for the psychotherapeutic group functioning.
Course description of a psychotherapeutic group, composed by patients with eating disorders (bulimia nervosa and binge eating disorder) in the context of a specialized hospital day.
A patient – who has recently had a breakup – asked help to the group through a non-reported whatsapp chat. Gradually, patients used this new channel to express distress and daily interpersonal difficulties, showing less implication in the supervised group sessions. The patient presented a symptomatic relapse with self-harm injuries and severe eating symptoms. Finally, she left the therapy and, in the next weeks, other patients also left the group, due to different reasons, in a “drag phenomenon”. The analysis showed that the formation of this outgroup socialization changed the relationships between members and new roles were taken.
It is necessary to early address the formation of outgroup socialization in the pre-group interview, emphasizing its high risk for the future group functioning. Therapists should consider that out-group communication is common and easy due to new technologies, so the use of specific questionnaires about this issue may prevent or detect pathological events.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
OBJECTIVES/SPECIFIC AIMS: The overall goal of this project is to enhance the use of GCRA in Latina breast cancer survivors at high risk of hereditary breast and ovarian cancer to reduce disparities in GCRA uptake. The aims of the study are to (1) develop a cultural adaptation of an evidence-based TGC intervention that consists of phone genetic counseling and a booklet, (2) evaluate the impact of TGC Versus Usual Care, and (3) explore the communication patterns in TGC and genetic counseling sessions with an interpreter. METHODS/STUDY POPULATION: We are conducting a 2-phase, mixed methods study. In Phase I we will develop a cultural adaption of an evidence-based intervention (TGC) for high-risk Latina breast cancer survivors using the Learner Verification and Revision Framework (n=15). In Phase II we will use a cluster randomized design with four community sites randomized to Spanish TGC (n=2 sites) or usual care (n=2 sites) (n=60; 15 per site). The primary outcome is genetic counseling uptake. Among women who receive genetic counseling either through TGC (n~30) or with an interpreter (n~15), we will assess counseling quality by reviewing 20 randomly selected audiotaped sessions (10 TGC; 10 interpreters). We will evaluate women’s HBOC knowledge and satisfaction with counseling. Communication processes and outcomes will be assessed using gold standard RIAS quantitative coding system and qualitative discourse analysis. RESULTS/ANTICIPATED RESULTS: We elicited input from transdisciplinary team members to develop an initial adaptation of a TGC print booklet and intervention protocol for use with high-risk Latina breast cancer survivors with limited English proficiency. The booklet contains low-literacy information about HBOC, risk factors, pros and cons of testing, and management strategies. Based on these materials and prior work, we anticipate TGC will consist of one 1 hour or less TGC session by phone. Participants interested in pursuing testing will receive a saliva kit and will participate in a second TGC session (30 min) to discuss test results and management options. DISCUSSION/SIGNIFICANCE OF IMPACT: Given access barriers and the shortage of Spanish-speaking genetic counselors, adapting and translating TGC intervention is a promising strategy that could reduce disparities by broadening the reach and accessibility to genetic counseling while enhancing the quality of the service for Latinas with limited English proficiency.