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1.
Rev. neurol. (Ed. impr.) ; 78(7): 199-207, Ene-Jun, 2024. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-232186

RESUMO

Introducción: El neurocientífico español Justo Gonzalo y Rodríguez-Leal (1910-1986) investiga la organización funcional de la corteza cerebral durante más de cuatro décadas. Sus hallazgos le llevan a formular una teoría neurofisiológica basada en las leyes de la excitabilidad nerviosa, que denomina dinámica cerebral. En el presente trabajo se expone de forma cronológica cómo surgen las principales ideas sobre las que se articula.Desarrollo: En 1939 Gonzalo observa los denominados fenómenos de acción dinámica: desfasamiento, facilitación y repercusión cerebral. Le siguen dos principios: efecto cerebral de la lesión según la magnitud y posición (1941), y organización sensorial, según un desarrollo espiral (1947). Paralelamente, caracteriza lo que llama el síndrome central de la corteza cerebral. En la década de los cincuenta desarrolla los conceptos de gradiente cortical, similitud y alometría. En contraposición a las concepciones modulares de la corteza cerebral, en las que una región es responsable de una función, Gonzalo expresa que ‘los gradientes corticales dan la localización de los sistemas mientras la similitud y alometría revelan su trama funcional’.Conclusiones: La teoría de dinámica cerebral se articula en dos etapas. La primera (de 1938 a 1950) se caracteriza por una importante base clínica con observación de nuevos fenómenos y formulación de nuevos conceptos. La segunda (de 1950 a 1960) incluye la introducción de conceptos de mayor alcance, como el gradiente funcional cortical, y leyes de alometría que se basan en un cambio de escala. Actualmente, varios autores consideran que el concepto de gradiente es clave para entender la organización cerebral.(AU)


Introduction: The Spanish neuroscientist Justo Gonzalo y Rodríguez-Leal (1910-1986) investigated the functional organisation of the cerebral cortex over more than four decades. His findings led him to formulate a neurophysiological theory based on the laws of nervous excitability, which he called brain dynamics. This paper presents in chronological order how the main ideas on which it is based arose.Development: In 1939, Gonzalo observed the phenomena of dynamic action: asynchrony or disaggregation, facilitation and cerebral repercussion. This was followed by two principles: the cerebral effect of lesions according to their magnitude and position (1941), and spiral development of the sensory field (1947). At the same time, he characterised what he called the central syndrome of the cerebral cortex. In the 1950s he developed the concepts of the cortical gradient, similarity and allometry. In contrast to modular conceptions of the cerebral cortex, in which one region is responsible for one function, Gonzalo argued that ‘cortical gradients provide the location of systems, while similarity and allometry reveal their functional mechanism.’Conclusions: The theory of brain dynamics was established in two stages. The first (between 1938 and 1950) had an important clinical foundation, involving the observation of new phenomena and the formulation of new concepts. The second (between 1950 and 1960) included the introduction of more far-reaching concepts, such as the functional cortical gradient, and allometry laws based on a change of scale. Today, various authors believe that the concept of the gradient is crucial for understanding how the brain is organised.(AU)


Assuntos
Humanos , Masculino , Feminino , Córtex Cerebral , Córtex Cerebral/anatomia & histologia , Neurologia/história , Cérebro/anatomia & histologia , Neurofisiologia
2.
Commun Biol ; 7(1): 436, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600295

RESUMO

Oviraptorosaurians were a theropod dinosaur group that reached high diversity in the Late Cretaceous. Within oviraptorosaurians, the later diverging oviraptorids evolved distinctive crania which were extensively pneumatised, short and tall, and had a robust toothless beak, interpreted as providing a powerful bite for their herbivorous to omnivorous diet. The present study explores the ability of oviraptorid crania to resist large mechanical stresses compared with other theropods and where this adaptation originated within oviraptorosaurians. Digital 3D cranial models were constructed for the earliest diverging oviraptorosaurian, Incisivosaurus gauthieri, and three oviraptorids, Citipati osmolskae, Conchoraptor gracilis, and Khaan mckennai. Finite element analyses indicate oviraptorosaurian crania were stronger than those of other herbivorous theropods (Erlikosaurus and Ornithomimus) and were more comparable to the large, carnivorous Allosaurus. The cranial biomechanics of Incisivosaurus align with oviraptorids, indicating an early establishment of distinctive strengthened cranial biomechanics in Oviraptorosauria, even before the highly modified oviraptorid cranial morphology. Bite modelling, using estimated muscle forces, suggests oviraptorid crania may have functioned closer to structural safety limits. Low mechanical stresses around the beaks of oviraptorids suggest a convergently evolved, functionally distinct rhamphotheca, serving as a cropping/feeding tool rather than for stress reduction, when compared with other herbivorous theropods.


Assuntos
Dinossauros , Fósseis , Animais , Crânio/anatomia & histologia , Dinossauros/anatomia & histologia , Herbivoria , Dieta
3.
Nature ; 628(8008): 563-568, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38600379

RESUMO

More than a quarter of the world's tropical forests are exploited for timber1. Logging impacts biodiversity in these ecosystems, primarily through the creation of forest roads that facilitate hunting for wildlife over extensive areas. Forest management certification schemes such as the Forest Stewardship Council (FSC) are expected to mitigate impacts on biodiversity, but so far very little is known about the effectiveness of FSC certification because of research design challenges, predominantly limited sample sizes2,3. Here we provide this evidence by using 1.3 million camera-trap photos of 55 mammal species in 14 logging concessions in western equatorial Africa. We observed higher mammal encounter rates in FSC-certified than in non-FSC logging concessions. The effect was most pronounced for species weighing more than 10 kg and for species of high conservation priority such as the critically endangered forest elephant and western lowland gorilla. Across the whole mammal community, non-FSC concessions contained proportionally more rodents and other small species than did FSC-certified concessions. The first priority for species protection should be to maintain unlogged forests with effective law enforcement, but for logged forests our findings provide convincing data that FSC-certified forest management is less damaging to the mammal community than is non-FSC forest management. This study provides strong evidence that FSC-certified forest management or equivalently stringent requirements and controlling mechanisms should become the norm for timber extraction to avoid half-empty forests dominated by rodents and other small species.


Assuntos
Certificação , Agricultura Florestal , Florestas , Mamíferos , Animais , África Ocidental , Biodiversidade , Peso Corporal , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Elefantes , Agricultura Florestal/legislação & jurisprudência , Agricultura Florestal/métodos , Agricultura Florestal/normas , Gorilla gorilla , Mamíferos/anatomia & histologia , Mamíferos/classificação , Mamíferos/fisiologia , Fotografação , Roedores , Masculino , Feminino
4.
BMC Oral Health ; 24(1): 436, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600486

RESUMO

The anatomy of furcation favours the bacterial retention and makes periodontal debridement as well as oral hygiene procedures difficult. Teeth that have lost attachment to a level of the furcation are said to have a furcal invasion or furcation involved.Involvement of furcation in a multi-rooted tooth poses a very different type of clinical situation in terms of establishment of diagnosis, determination of prognosis and of course planning the treatment modality.The present study was carried out on 200 selected extracted human first and second permanent molar teeth based on a predefined criteria. Teeth with prosthetic crowns, fused or fractured roots, those not fully developed, grossly carious or heavily restored at the cementoenamel junction (CEJ) were excluded from the study. The morphology of the root trunk was recorded by measuring various dimensions of the root trunk,including furcal angle and root trunk volume was calculated by using a custom made special apparatus. The furcation areas were debrided with different types of curettes in the market in order to see how best the instrument could be maneuvered in the furcation area. The data so obtained was statistically analysed using SPSS version 22. The highest root trunk volume and the longest root trunk length were found to be in the maxillary second molar. 48.60% furcations didn't allow instrument engagementof furcation area with standard area specific curettes. The proposal of inclusion of root trunk length (mm) is suggested in addition to classification of FI to have assess prognosis and appropriate treatment for of the involved tooth.


Assuntos
Defeitos da Furca , Raiz Dentária , Humanos , Raiz Dentária/anatomia & histologia , Dente Molar/cirurgia , Dente Molar/anatomia & histologia , Colo do Dente , Prognóstico , Biometria , Defeitos da Furca/cirurgia , Defeitos da Furca/diagnóstico
5.
Theor Appl Genet ; 137(5): 110, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656338

RESUMO

KEY MESSAGE: We developed T1AL·1PS and T1AS·1PL Robertsonian translocations by breakage-fusion mechanism based on wheat-A. cristatum 1P(1A) substitution line with smaller leaf area, shorter plant height, and other excellent agronomic traits Agropyron cristatum, a wild relative of wheat, is a valuable germplasm resource for improving wheat genetic diversity and yield. Our previous study confirmed that the A. cristatum chromosome 1P carries alien genes that reduce plant height and leaf size in wheat. Here, we developed T1AL·1PS and T1AS·1PL Robertsonian translocations (RobTs) by breakage-fusion mechanism based on wheat-A. cristatum 1P (1A) substitution line II-3-1c. Combining molecular markers and cytological analysis, we identified 16 spontaneous RobTs from 911 F2 individuals derived from the cross of Jimai22 and II-3-1c. Fluorescence in situ hybridization (FISH) was applied to detect the fusion structures of the centromeres in wheat and A. cristatum chromosomes. Resequencing results indicated that the chromosomal junction point was located at the physical position of Triticum aestivum chromosome 1A (212.5 Mb) and A. cristatum chromosome 1P (230 Mb). Genomic in situ hybridization (GISH) in pollen mother cells showed that the produced translocation lines could form stable ring bivalent. Introducing chromosome 1PS translocation fragment into wheat significantly increased the number of fertile tillers, grain number per spike, and grain weight and reduced the flag leaf area. However, introducing chromosome 1PL translocation fragment into wheat significantly reduced flag leaf area and plant height with a negative effect on yield components. The pre-breeding of two spontaneous RobTs T1AL·1PS and T1AS·1PL was important for wheat architecture improvement.


Assuntos
Agropyron , Cromossomos de Plantas , Melhoramento Vegetal , Translocação Genética , Triticum , Triticum/genética , Triticum/crescimento & desenvolvimento , Triticum/anatomia & histologia , Agropyron/genética , Agropyron/crescimento & desenvolvimento , Cromossomos de Plantas/genética , Hibridização in Situ Fluorescente , Fenótipo
6.
J Strength Cond Res ; 38(5): 951-956, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38662887

RESUMO

ABSTRACT: González-Cano, H, Martín-Olmedo, JJ, Baz-Valle, E, Contreras, C, Schoenfeld, BJ, García-Ramos, A, Jiménez-Martínez, P, and Alix-Fages, C. Do muscle mass and body fat differ between elite and amateur natural physique athletes on competition day? A preliminary, cross-sectional, anthropometric study. J Strength Cond Res 38(5): 951-956, 2024-Natural physique athletes strive to achieve low body fat levels while promoting muscle mass hypertrophy for competition day. This study aimed to compare the anthropometric characteristics of natural amateur (AMA) and professional (PRO) World Natural Bodybuilding Federation (WNBF) competitors. Eleven male natural physique athletes (6 PRO and 5 AMA; age = 24.8 ± 2.3 years) underwent a comprehensive anthropometric evaluation following the International Society for the Advancement of Kinanthropometry protocol within a 24-hour time frame surrounding the competition. The 5-component fractionation method was used to obtain the body composition profile of the muscle, adipose, bone, skin, and residual tissues. Five physique athletes exceeded the 5.2 cutoff point of muscle-to-bone ratio (MBR) for natural athletes. Professional physique athletes were older than AMA physique athletes (p = 0.05), and they also presented larger thigh girths (p = 0.005) and bone mass (p = 0.019) compared with AMA physique athletes. Although no statistically significant between-group differences were observed in body mass, height, or body fat levels, PRO physique athletes exhibited a higher body mass index (BMI; AMA: 24.45 ± 0.12; PRO: 25.52 ± 1.01; p = 0.048), lean body mass (LBM; AMA: 64.49 ± 2.35; PRO: 69.80 ± 3.78; p = 0.024), fat-free mass (FFM; AMA: 71.23 ± 3.21; PRO: 76.52 ± 4.31; p = 0.05), LBM index (LBMI; AMA: 20.65 ± 0.52; PRO: 21.74 ± 0.85; p = 0.034), and fat-free mass index index (FFMI; AMA: 22.80 ± 0.22; PRO: 23.83 ± 0.90; p = 0.037) compared with AMA physique athletes. These findings highlight the unique characteristics and anthropometric differences between PRO and AMA natural physique athletes on competition day, emphasizing the significance of age, thigh girth, bone mass, BMI, LBM, FFM, and FFMI in distinguishing these 2 groups. Based on our findings, the established boundaries for muscle mass in natural physique athletes, based on FFMI and MBR, warrant reconsideration.


Assuntos
Tecido Adiposo , Antropometria , Atletas , Composição Corporal , Músculo Esquelético , Humanos , Masculino , Estudos Transversais , Adulto Jovem , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/fisiologia , Músculo Esquelético/fisiologia , Músculo Esquelético/anatomia & histologia , Adulto , Composição Corporal/fisiologia , Levantamento de Peso/fisiologia
7.
Sci Rep ; 14(1): 9488, 2024 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664414

RESUMO

In this work we endeavor to further understand the genetic architecture of the cerebellum by examining the genetic underpinnings of the different cerebellar lob(ul)es, identifying their genetic relation to cortical and subcortical regions, as well as to psychiatric disorders, as well as traces of their evolutionary trajectories. We confirm the moderate heritability of cerebellar volumes, and reveal genetic clustering and variability across their different substructures, which warranted a detailed analysis using this higher structural resolution. We replicated known genetic correlations with several subcortical volumes, and report new cortico-cerebellar genetic correlations, including negative genetic correlations between anterior cerebellar lobules and cingulate, and positive ones between lateral Crus I and lobule VI with cortical measures in the fusiform region. Heritability partitioning for evolutionary annotations highlighted that the vermis of Crus II has depleted heritability in genomic regions of "archaic introgression deserts", but no enrichment/depletion of heritability in any other cerebellar regions. Taken together, these findings reveal novel insights into the genetic underpinnings of the different cerebellar lobules.


Assuntos
Bancos de Espécimes Biológicos , Cerebelo , Humanos , Cerebelo/anatomia & histologia , Masculino , Feminino , Reino Unido , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética , Idoso , 60682
8.
BMC Plant Biol ; 24(1): 338, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664642

RESUMO

Proper pericarp thickness protects the maize kernel against pests and diseases, moreover, thinner pericarp improves the eating quality in fresh corn. In this study, we aimed to investigate the dynamic changes in maize pericarp during kernel development and identified the major quantitative trait loci (QTLs) for maize pericarp thickness. It was observed that maize pericarp thickness first increased and then decreased. During the growth and formation stages, the pericarp thickness gradually increased and reached the maximum, after which it gradually decreased and reached the minimum during maturity. To identify the QTLs for pericarp thickness, a BC4F4 population was constructed using maize inbred lines B73 (recurrent parent with thick pericarp) and Baimaya (donor parent with thin pericarp). In addition, a high-density genetic map was constructed using maize 10 K SNP microarray. A total of 17 QTLs related to pericarp thickness were identified in combination with the phenotypic data. The results revealed that the heritability of the thickness of upper germinal side of pericarp (UG) was 0.63. The major QTL controlling UG was qPT1-1, which was located on chromosome 1 (212,215,145-212,948,882). The heritability of the thickness of upper abgerminal side of pericarp (UA) was 0.70. The major QTL controlling UA was qPT2-1, which was located on chromosome 2 (2,550,197-14,732,993). In addition, a combination of functional annotation, DNA sequencing analysis and quantitative real-time PCR (qPCR) screened two candidate genes, Zm00001d001964 and Zm00001d002283, that could potentially control maize pericarp thickness. This study provides valuable insights into the improvement of maize pericarp thickness during breeding.


Assuntos
Mapeamento Cromossômico , Locos de Características Quantitativas , Zea mays , Locos de Características Quantitativas/genética , Zea mays/genética , Zea mays/anatomia & histologia , Zea mays/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/anatomia & histologia , Fenótipo , Cromossomos de Plantas/genética , Polimorfismo de Nucleotídeo Único
9.
BMC Vet Res ; 20(1): 157, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664826

RESUMO

BACKGROUND: Bactrian camel is one of the important economic animals in northwest China. They live in arid desert, and their gestation period is about 13 months, which is longer than other ruminants (such as cattle and sheep). The harsh living conditions have made its unique histological characteristics a research focus. Aggregated lymphoid nodules area (ALNA) in the abomasum of Bactrian camels, as one of the most important sites for the induction of the immune response, provide a comprehensive and effective protective role for the organism, and their lack of information will affect the feeding management, reproduction and epidemic prevention of Bactrian camels. In this study, the histological characteristics of the fetal ALNA in the abomasum of Bactrian camels at different developmental gestation have been described by using light microscopy and histology . RESULTS: The ALNA in the abomasum of the Chinese Alashan Bactrian camel is a special immune structure that was first discovered and reported by Wen-hui Wang. To further establish the developmental characteristics of this special structure in the embryonic stage, the abomasum ALNA of 8 fetuses of Alashan Bactrian camels with different gestational ages (5~13 months) were observed and studied by anatomy and histology. The results showed that the aggregation of reticular epithelial cells (RECs) surrounded by a very small number of lymphoid cells was detected for the first time in the abomasum of fetal camel at 5 months gestation, which was presumed to be primitive ALNA. At 7 months gestation, the reticular mucosal folds region (RMFR) appeared, but the longitudinal mucosal folds region (LMFR) was not significant, and histological observations showed that there were diffusely distributed lymphocytes around the RECs. At 10months gestation, RMFR and LMFR were clearly visible, lymphoid follicles appeared in histological observation, lymphocytes proliferated vigorously. By 13 months, the volume of lymphoid follicles increased, forming the subepithelial dome (SED), and there was a primitive interfollicular area between the lymphoid follicles, which contained high endothelial vein (HEV), but no germinal center (GC) was found. In summary, ALNA of Bactrian camels is not fully mature before birth. CONCLUSIONS: Generally, the small intestine PPs of ruminants (such as cattle and sheep) is already mature before birth, while the ALNA in the abomasum of Bactrian camels is not yet mature in the fetal period. During the development of ALNA in Bactrian camel, the development of lymphoid follicles extends from submucosa to Lamina propria. Interestingly, the deformation of FAE changes with age from simple columnar epithelium at the beginning of pregnancy to Simple cuboidal epithelium, which is opposite to the FAE deformation characteristics of PPs in the small intestine of fetal cattle and sheep. These results are the basis of further research on the specificity of ALNA in the abomasum of Bactrian camels.


Assuntos
Abomaso , Camelus , Animais , Camelus/anatomia & histologia , Camelus/embriologia , Feminino , Tecido Linfoide/anatomia & histologia , Tecido Linfoide/crescimento & desenvolvimento , Feto , Gravidez
10.
J Comp Neurol ; 532(3): e25597, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38588163

RESUMO

Although the brain fills nearly the entire cranial cavity in birds, it can occupy a small portion of it in crocodilians. The lack of data regarding the volumetric correspondence between the brain and the cranial cavity hampers thorough assessments of the degree of encephalization in non-neornithean dinosaurs and other extinct archosaurs and, consequently, informed inferences regarding their cognitive capacities. Existing data suggest that, across extant archosaurs, the degree of endocranial doming and the volume of intracranial nonneural components are inversely related. We build upon this information to develop an equation relating these two anatomical features in non-neornithean dinosaurs and other extinct archosaurs. We rely on measurements of the endocast doming and brain-to-endocranial cavity (BEC) index in extant relatives of non-neornithean dinosaurs, namely, the crurotarsans Caiman crocodilus, Crocodylus niloticus, and Crocodylus porosus; the paleognaths Struthio camelus and Apteryx mantelli; and the fowl Macrocephalon maleo, Gallus gallus, Meleagris gallopavo, Phasianus colchicus, and Anas platyrhynchos. Applying the equation to representative endocasts from major clades of dinosaurs, we found that BEC varies from about 0.6 in ceratopsians and thyreophorans to around 0.7 in ornithopods, pachycephalosaurians, sauropods, and theropods. We, therefore, warn against the use of a catch-all value, like 0.5, and instead encourage refinement in the adoption of BEC across archosaurs.


Assuntos
Jacarés e Crocodilos , Dinossauros , Animais , Filogenia , Crânio/anatomia & histologia , Galinhas , Encéfalo , Evolução Biológica , Fósseis
11.
Proc Natl Acad Sci U S A ; 121(16): e2313820121, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38598343

RESUMO

In primates, high-acuity vision is mediated by the fovea, a small specialized central region of the retina. The fovea, unique to the anthropoid lineage among mammals, undergoes notable neuronal morphological changes during postnatal maturation. However, the extent of cellular similarity across anthropoid foveas and the molecular underpinnings of foveal maturation remain unclear. Here, we used high-throughput single-cell RNA sequencing to profile retinal cells of the common marmoset (Callithrix jacchus), an early divergent in anthropoid evolution from humans, apes, and macaques. We generated atlases of the marmoset fovea and peripheral retina for both neonates and adults. Our comparative analysis revealed that marmosets share almost all their foveal types with both humans and macaques, highlighting a conserved cellular structure among primate foveas. Furthermore, by tracing the developmental trajectory of cell types in the foveal and peripheral retina, we found distinct maturation paths for each. In-depth analysis of gene expression differences demonstrated that cone photoreceptors and Müller glia (MG), among others, show the greatest molecular divergence between these two regions. Utilizing single-cell ATAC-seq and gene-regulatory network inference, we uncovered distinct transcriptional regulations differentiating foveal cones from their peripheral counterparts. Further analysis of predicted ligand-receptor interactions suggested a potential role for MG in supporting the maturation of foveal cones. Together, these results provide valuable insights into foveal development, structure, and evolution.


Assuntos
Callithrix , Retina , Humanos , Animais , Recém-Nascido , Callithrix/anatomia & histologia , Retina/metabolismo , Fóvea Central/fisiologia , Células Fotorreceptoras Retinianas Cones , Macaca , Mamíferos
12.
J Comp Neurol ; 532(4): e25617, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38629472

RESUMO

The New World suboscines (Passeriformes and Tyrannides) are one of the biggest endemic vertebrate radiations in South America, including the families Furnariidae and Tyrannidae. Avian brain morphology is a reliable proxy to study their evolution. The aim of this work is to elucidate whether the brains of these families reflect the ecological differences (e.g., feeding behavior) and to clarify macroevolutionary aspects of their neuroanatomy. Our hypotheses are as follows: Brain size is similar between both families and with other Passeriformes; brain morphology in Tyrannides is the result of the pressure of ecological factors; and brain disparity is low since they share ecological traits. Skulls of Furnariidae and Tyrannidae were micro-computed tomography-scanned, and three-dimensional models of the endocast were generated. Regression analyses were performed between brain volume and body mass. Linear and surface measurements were used to build phylomorphospaces and to calculate the amount of phylogenetic signal. Tyrannidae showed a larger brain disparity than Furnariidae, although it is not shaped by phylogeny in the Tyrannides. Furnariidae present enlarged Wulsts (eminentiae sagittales) but smaller optic lobes, while in Tyrannidae, it is the opposite. This could indicate that in Tyrannides there is a trade-off between the size of these two visual-related brain structures.


Assuntos
Passeriformes , Animais , Humanos , Passeriformes/anatomia & histologia , Filogenia , Microtomografia por Raio-X , Encéfalo/anatomia & histologia
13.
Nature ; 628(8009): 795-803, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38632396

RESUMO

Insects constitute the most species-rich radiation of metazoa, a success that is due to the evolution of active flight. Unlike pterosaurs, birds and bats, the wings of insects did not evolve from legs1, but are novel structures that are attached to the body via a biomechanically complex hinge that transforms tiny, high-frequency oscillations of specialized power muscles into the sweeping back-and-forth motion of the wings2. The hinge consists of a system of tiny, hardened structures called sclerites that are interconnected to one another via flexible joints and regulated by the activity of specialized control muscles. Here we imaged the activity of these muscles in a fly using a genetically encoded calcium indicator, while simultaneously tracking the three-dimensional motion of the wings with high-speed cameras. Using machine learning, we created a convolutional neural network3 that accurately predicts wing motion from the activity of the steering muscles, and an encoder-decoder4 that predicts the role of the individual sclerites on wing motion. By replaying patterns of wing motion on a dynamically scaled robotic fly, we quantified the effects of steering muscle activity on aerodynamic forces. A physics-based simulation incorporating our hinge model generates flight manoeuvres that are remarkably similar to those of free-flying flies. This integrative, multi-disciplinary approach reveals the mechanical control logic of the insect wing hinge, arguably among the most sophisticated and evolutionarily important skeletal structures in the natural world.


Assuntos
Voo Animal , Aprendizado de Máquina , Asas de Animais , Animais , Asas de Animais/fisiologia , Asas de Animais/anatomia & histologia , Fenômenos Biomecânicos , Voo Animal/fisiologia , Músculos/fisiologia , Músculos/anatomia & histologia , Robótica , Masculino , Drosophila melanogaster/fisiologia , Drosophila melanogaster/anatomia & histologia , Redes Neurais de Computação , Feminino
14.
Nature ; 628(8009): 811-817, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38632397

RESUMO

Hybridization allows adaptations to be shared among lineages and may trigger the evolution of new species1,2. However, convincing examples of homoploid hybrid speciation remain rare because it is challenging to demonstrate that hybridization was crucial in generating reproductive isolation3. Here we combine population genomic analysis with quantitative trait locus mapping of species-specific traits to examine a case of hybrid speciation in Heliconius butterflies. We show that Heliconius elevatus is a hybrid species that is sympatric with both parents and has persisted as an independently evolving lineage for at least 180,000 years. This is despite pervasive and ongoing gene flow with one parent, Heliconius pardalinus, which homogenizes 99% of their genomes. The remaining 1% introgressed from the other parent, Heliconius melpomene, and is scattered widely across the H. elevatus genome in islands of divergence from H. pardalinus. These islands contain multiple traits that are under disruptive selection, including colour pattern, wing shape, host plant preference, sex pheromones and mate choice. Collectively, these traits place H. elevatus on its own adaptive peak and permit coexistence with both parents. Our results show that speciation was driven by introgression of ecological traits, and that speciation with gene flow is possible with a multilocus genetic architecture.


Assuntos
Borboletas , Fluxo Gênico , Introgressão Genética , Especiação Genética , Hibridização Genética , Locos de Características Quantitativas , Simpatria , Animais , Borboletas/genética , Borboletas/classificação , Locos de Características Quantitativas/genética , Masculino , Feminino , Simpatria/genética , Isolamento Reprodutivo , Preferência de Acasalamento Animal , Especificidade da Espécie , Asas de Animais/anatomia & histologia , Seleção Genética , Fenótipo , Genoma de Inseto/genética , Pigmentação/genética
15.
Commun Biol ; 7(1): 477, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637627

RESUMO

The amygdala nuclei modulate distributed neural circuits that most likely evolved to respond to environmental threats and opportunities. So far, the specific role of unique amygdala nuclei in the context processing of salient environmental cues lacks adequate characterization across neural systems and over time. Here, we present amygdala nuclei morphometry and behavioral findings from longitudinal population data (>1400 subjects, age range 40-69 years, sampled 2-3 years apart): the UK Biobank offers exceptionally rich phenotyping along with brain morphology scans. This allows us to quantify how 18 microanatomical amygdala subregions undergo plastic changes in tandem with coupled neural systems and delineating their associated phenome-wide profiles. In the context of population change, the basal, lateral, accessory basal, and paralaminar nuclei change in lockstep with the prefrontal cortex, a region that subserves planning and decision-making. The central, medial and cortical nuclei are structurally coupled with the insular and anterior-cingulate nodes of the salience network, in addition to the MT/V5, basal ganglia, and putamen, areas proposed to represent internal bodily states and mediate attention to environmental cues. The central nucleus and anterior amygdaloid area are longitudinally tied with the inferior parietal lobule, known for a role in bodily awareness and social attention. These population-level amygdala-brain plasticity regimes in turn are linked with unique collections of phenotypes, ranging from social status and employment to sleep habits and risk taking. The obtained structural plasticity findings motivate hypotheses about the specific functions of distinct amygdala nuclei in humans.


Assuntos
Tonsila do Cerebelo , Fenômica , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Tonsila do Cerebelo/diagnóstico por imagem , Tonsila do Cerebelo/anatomia & histologia , Gânglios da Base , Córtex Pré-Frontal
16.
Am J Bot ; 111(4): e16321, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38659272

RESUMO

PREMISE: We studied the 3D morphology of a small, well-preserved cone from the Pennsylvanian Mazon Creek Lagerstätte to characterize its structure and determine its systematic affinity. Previously tentatively assigned to the enigmatic Tetraphyllostrobus, we show that it differs in key respects from that genus as described. METHODS: We systematically compared the new fossil with relevant Paleozoic cone genera and employed advanced imaging techniques, including scanning electron microscopy, Airyscan confocal super-resolution microscopy, optical microscopy, and X-ray microcomputed tomography to visualize and reconstruct the fossil cone in 3D. RESULTS: The analyses demonstrate unequivocally that the sporophylls of the new Mazon Creek cone are arranged in whorls of six and have characters typical of Sphenophyllales, including epidermal cells with undulatory margins and in situ spores assignable to Columinisporites. The combination of characters, including sporophyll arrangement, anatomy, and spore type, supports the establishment of Hexaphyllostrobus kostorhysii gen. et sp. nov. within Sphenophyllales. Furthermore, we show that Tetraphyllostrobus, although originally described as possessing smooth monolete spores, actually possesses Columinisporites-type spores, indicating that it, too, was most likely a sphenophyll. CONCLUSIONS: The recognition of Hexaphyllostrobus contributes to our knowledge of Pennsylvanian sphenophyll diversity, and in particular increases the number of species with in situ Columinisporites-type spores. Attribution of Hexaphyllostrobus to Sphenophyllales calls into question current interpretations of Tetraphyllostrobus suggesting that future research on better-preserved macrofossil material may demonstrate a sphenophyllalean relationship.


Assuntos
Fósseis , Fósseis/anatomia & histologia , Microtomografia por Raio-X , Microscopia Eletrônica de Varredura , Traqueófitas/anatomia & histologia , Traqueófitas/ultraestrutura
17.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 55(2): 290-296, 2024 Mar 20.
Artigo em Chinês | MEDLINE | ID: mdl-38645855

RESUMO

Objective: To study the microanatomic structure of the subtemporal transtentorial approach to the lateral side of the brainstem, and to provide anatomical information that will assist clinicians to perform surgeries on the lateral, circumferential, and petroclival regions of the brainstem. Methods: Anatomical investigations were conducted on 8 cadaveric head specimens (16 sides) using the infratemporal transtentorial approach. The heads were tilted to one side, with the zygomatic arch at its highest point. Then, a horseshoe incision was made above the auricle. The incision extended from the midpoint of the zygomatic arch to one third of the mesolateral length of the transverse sinus, with the flap turned towards the temporal part. After removing the bone, the arachnoid and the soft meninges were carefully stripped under the microscope. The exposure range of the surgical approach was observed and the positional relationships of relevant nerves and blood vessels in the approach were clarified. Important structures were photographed and the relevant parameters were measured. Results: The upper edge of the zygomatic arch root could be used to accurately locate the base of the middle cranial fossa. The average distances of the star point to the apex of mastoid, the star point to the superior ridge of external auditory canal, the anterior angle of parietomastoid suture to the superior ridge of external auditory canal, and the anterior angle of parietomastoid suture to the star point of the 10 adult skull specimens were 47.23 mm, 45.27 mm, 26.16 mm, and 23.08 mm, respectively. The subtemporal approach could fully expose the area from as high as the posterior clinoid process to as low as the petrous ridge and the arcuate protuberance after cutting through the cerebellar tentorium. The approach makes it possible to handle lesions on the ventral or lateral sides of the middle clivus, the cistern ambiens, the midbrain, midbrain, and pons. In addition, the approach can significantly expand the exposure area of the upper part of the tentorium cerebelli through cheekbone excision and expand the exposure range of the lower part of the tentorium cerebelli through rock bone grinding technology. The total length of the trochlear nerve, distance of the trochlear nerve to the tentorial edge of cerebellum, length of its shape in the tentorial mezzanine, and its lower part of entering into the tentorium cerebelli to the petrosal ridge were (16.95±4.74) mm, (1.27±0.73) mm, (5.72±1.37) mm, and (4.51±0.39) mm, respectively. The cerebellar tentorium could be safely opened through the posterior clinoid process or arcuate protrusion for localization. The oculomotor nerve could serve as an anatomical landmark to locate the posterior cerebral artery and superior cerebellar artery. Conclusion: Through microanatomic investigation, the exposure range and intraoperative difficulties of the infratemporal transtentorial approach can be clarified, which facilitates clinicians to accurately and safely plan surgical methods and reduce surgical complications.


Assuntos
Cadáver , Humanos , Tronco Encefálico/anatomia & histologia , Tronco Encefálico/cirurgia , Osso Temporal/anatomia & histologia , Osso Temporal/cirurgia , Fossa Craniana Média/anatomia & histologia , Fossa Craniana Média/cirurgia , Craniotomia/métodos
18.
Int J Community Based Nurs Midwifery ; 12(2): 121-134, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38650960

RESUMO

Background: Despite the increasing growth of female genital cosmetic procedures, the long-term effects of these procedures are not clearly understood. This study was conducted to compare the genital self-image and sexual function in women with and without female genital cosmetic procedures. Methods: This cross-sectional study was conducted on 315 participants (210 women without a history of genital cosmetic surgery and 105 women with it) in Alborz province, Iran, from early February 2023 to mid-May 2023. The sampling was done conveniently. Data collection instruments were Female Genital Self Image Scale and Female Sexual Function Index. Statistical analysis was done in SPSS 16 software using t-test, chi-square, and logistic regression, and P<0.05 was considered statistically significant. Results: The use of laser to tighten the vagina with 77.77% and Perineoplasty with 29.2% were the main cosmetic procedures. The mean duration passed from the surgical procedures was 4.79±3.60 years, while it was 1.13±0.74 years for non-surgical procedures. Women with a history of genital procedures had a higher mean age (39.45±10.38, P=0.023). However, they were lower regarding the level of education (P<0.001), family income (P<0.001), and exercise (P<0.001). Also, they showed a higher number of pregnancies (P<0.001), deliveries (P<0.001), vaginal delivery (P<0.001), episiotomy (P<0.001), and neonates with a weight of ≥3.5 kg (P=0.002). In both groups, midwives and doctors were the most important sources of information about the appearance and function of reproductive system. However, the genital self-image and sexual function of the two groups did not differ significantly (P>0.05). Conclusion: No difference in sexual self-image and lack of difference in sexual function after cosmetic procedures show the need to pay attention to recommending and selecting these procedures. Public awareness about the diverse and natural forms of the female genitalia, education about the variety of the factors affecting sexual function, reduction of unnecessary interventions, increase in physiological births, retraining doctors and midwives, and multidimensional counseling can help to choose more appropriate candidates for cosmetic procedures.


Assuntos
Autoimagem , Humanos , Feminino , Estudos Transversais , Adulto , Irã (Geográfico) , Genitália Feminina/cirurgia , Genitália Feminina/anatomia & histologia , Pessoa de Meia-Idade , Imagem Corporal/psicologia , Comportamento Sexual/psicologia , Inquéritos e Questionários
19.
Planta ; 259(6): 131, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652171

RESUMO

MAIN CONCLUSION: The anatomical structures of Carex moorcroftii roots showing stronger plasticity during drought had a lower coefficient of variation in cell size in the same habitats, while those showing weaker plasticity had a higher coefficient of variation. The complementary relationship between these factors comprises the adaptation mechanism of the C. moorcroftii root to drought. To explore the effects of habitat drought on root anatomy of hygrophytic plants, this study focused on roots of C. moorcroftii. Five sample plots were set up along a soil moisture gradient in the Western Sichuan Plateau to collect experimental materials. Paraffin sectioning was used to obtain root anatomy, and one-way ANOVA, correlation analysis, linear regression analysis, and RDA ranking were applied to analyze the relationship between root anatomy and soil water content. The results showed that the root transverse section area, thickness of epidermal cells, exodermis and Casparian strips, and area of aerenchyma were significantly and positively correlated with soil moisture content (P < 0.01). The diameter of the vascular cylinder and the number and total area of vessels were significantly and negatively correlated with the soil moisture content (P < 0.01). The plasticity of the anatomical structures was strong for the diameter and area of the vascular cylinder and thickness of the Casparian strip and epidermis, while it was weak for vessel diameter and area. In addition, there was an asymmetrical relationship between the functional adaptation of root anatomical structure in different soil moisture and the variation degree of root anatomical structure in the same soil moisture. Therefore, the roots of C. moorcroftii can shorten the water transport distance from the epidermis to the vascular cylinder, increase the area of the vascular cylinder and the number of vessels, and establish a complementary relationship between the functional adaptation of root anatomical structure in different habitats and the variation degree of root anatomical structure in the same habitat to adapt to habitat drought. This study provides a scientific basis for understanding the response of plateau wetland plants to habitat changes and their ecological adaptation strategies. More scientific experimental methods should be adopted to further study the mutual coordination mechanisms of different anatomical structures during root adaptation to habitat drought for hygrophytic plants.


Assuntos
Carex (Planta) , Secas , Ecossistema , Raízes de Plantas , Solo , Água , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/fisiologia , China , Carex (Planta)/fisiologia , Carex (Planta)/anatomia & histologia , Água/fisiologia , Água/metabolismo , Adaptação Fisiológica
20.
Naturwissenschaften ; 111(3): 27, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652309

RESUMO

Re-evaluation of photographs of the tropical butterfly Morpho helenor from a previous study (Pignataro et al. 2023) revealed that its conclusion regarding increased wing fluctuating asymmetry in forest edge habitats compared to forest interior habitats could not be replicated. This discrepancy likely arises from (i) original measurements not being conducted blindly, (ii) insufficient photograph quality hindering accurate landmark selection, and (iii) a lack of detailed description of the measurement protocol. The likelihood of false positive discoveries within the published data concerning the impacts of environmental stress on the fluctuating asymmetry of plants and animals is probably higher than previously assumed.


Assuntos
Borboletas , Florestas , Borboletas/fisiologia , Borboletas/anatomia & histologia , Animais , Asas de Animais/anatomia & histologia , Asas de Animais/fisiologia , Ecossistema , Clima Tropical
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