289 research outputs found

    Phylogenetic patterns and diversity of embryonic skeletal ossification in Cetartiodactyla

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    Biogeographic variation in skull morphology across the Kra Isthmus in dusky leaf monkeys

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    Despite the growing literature on the underlying factors of geographical phenotypic variation, little is known about how and to what extent biogeographic barriers in South‐East Asia have shaped morphological variation in primates. We aimed to investigate the geographical variations in skull morphology in dusky leaf monkeys by decomposing them into clinal (latitudinal), non‐clinal spatial (discrete difference between regions north and south of the Isthmus of Kra), and environment‐related components. We applied geometric morphometrics to measure 53 adult male specimens from 36 localities, covering the regions both north and south of the Isthmus of Kra. A linear model was used to test the effects of region (north vs. south of the Isthmus of Kra), latitude, and environmental factors (temperature and rainfall) on the size and shape of skulls. A part of variation in skull shape differed moderately between the regions in the north and south of the Isthmus of Kra, and this difference cannot be explained by latitudinal and environmental factors. However, for size and the majority of variations in shape, we detected limited contributions of region and the two environmental factors. Shape differentiation that was unexplained by latitudinal and environmental factors suggests that dusky leaf monkeys may have experienced a population division due to habitat constriction around the Isthmus of Kra. However, this divergence probably has been obscured by subsequent gene flow between populations after habitat recovery

    The vocal apparatus: An understudied tool to reconstruct the evolutionary history of echolocation in bats?

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    Laryngeal echolocation in bats could have evolved following two scenarios: a single origin from a common ancestor or an independent acquisition inside the two clades Yinpterochiroptera and Yangochiroptera. Later, some members of Yinpterochiroptera possibly lost their ability to echolocate. In bats, the larynx produces vocalizations for communication and, in most species, for echolocation. Here, we describe how comparative chiropteran laryngeal morphology is a novel area of research that could improve the understanding of echolocation and may help resolve the evolutionary history of bats. This review provides morphological descriptions and comparisons of the bat larynx and bioacoustics interpretations. We discuss the importance of understanding: (1) laryngeal sound production so it may be linked with the evolution of the chiropteran auditory system; and (2) the evolution of laryngeal morphology to understand the ecological and behavioural aspects of bat biology. We find that a strong phylogenetic signal is potentially the main source explaining macroevolutionary variation in laryngeal form among bats. We predict that the three parameters of sound production in echolocation (frequency, intensity, and rate of calls) are independently modulated by different laryngeal components, but this hypothesis remains understudied in terms of species diversity

    Unique bone microanatomy reveals ancestry of subterranean specializations in mammals

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    Acquiring a subterranean lifestyle entails a substantial shift for many aspects of terrestrial vertebrates’ biology. Although this lifestyle is associated with multiple instances of convergent evolution, the relative success of some subterranean lineages largely remains unexplained. Here, we focus on the mammalian transitions to life underground, quantifying bone microanatomy through high-resolution X-ray tomography. The true moles stand out in this dataset. Examination of this family's bone histology reveals that the highly fossorial moles acquired a unique phenotype involving large amounts of compacted coarse cancellous bone. This phenotype exceeds the adaptive optimum seemingly shared by several other subterranean mammals and can be traced back to some of the first known members of the family. This remarkable microanatomy was acquired early in the history of the group and evolved faster than the gross morphology innovations of true moles’ forelimb. This echoes the pattern described for other lifestyle transitions, such as the acquisition of bone mass specializations in secondarily aquatic tetrapods. Highly plastic traits—such as those pertaining to bone structure—are hence involved in the early stages of different types of lifestyle transitions

    Affecting factors for generalized trust in the concept of social capital

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    近年、コミュニティの再生やさまざまな社会問題克服のため、社会に対する市民的・積極的関与者を育成することが大きな目標とされ、その基盤としてソーシャル・キャピタルという概念が注目を集めている。本論においてはソーシャル・キャピタルの構成要素である一般的信頼に焦点をあて、二次データを用いて一般的信頼への規定要因の検討をおこなった。結果として高信頼者の特徴として(1)収入・学歴が高いこと(2)読書冊数が多く、テレビ視聴時間が短いこと(3)友人関係に満足していること(4)異質な他者に対して寛容であること(5)生活を支える組織に対して信頼を持っていることという五つの特徴が見出された。For reproducing communities, a great deal of attention has been paid on the concept of social capital. Generalized trust might be composed of social capital and its importance has been recognized in social capital research. In this paper, we analyzed some of the determinants of Generalized Trust with the secondary data. To sum up, people who trust other are : (1) being successful in terms of income and education; (2) reading books more and watching TV less; (3) being satisfied with friends; (4) being tolerant toward heterogeneous others; (5) trusting organizations which support his daily life

    Effective and convenient treatment of Xultophy with lower doses for elderly diabetic patient

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    The case is an 82-year-old female patient with Type 2 Diabetes Mellitus (T2DM) for 22 years. She developed right empyema in early January, 2021 and was treated by antibiotics and CT-guided drainage. After improving the status, she was transferred to Hayashi hospital, Tokushima, Japan. Treatment for T2DM was initially multiple daily insulin injection (MDI), but it could not continue because of injection several times a day by the family. Then, Xultophy was started once a day, which brought satisfactory glucose variability with lower doses. Consequently, Xultophy would be effective and useful agent from bio-psycho-social points of view

    Heterochrony and developmental modularity of cranial osteogenesis in lipotyphlan mammals

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    Background Here we provide the most comprehensive study to date on the cranial ossification sequence in Lipotyphla, the group which includes shrews, moles and hedgehogs. This unique group, which encapsulates diverse ecological modes, such as terrestrial, subterranean, and aquatic lifestyles, is used to examine the evolutionary lability of cranial osteogenesis and to investigate the modularity of development. Results An acceleration of developmental timing of the vomeronasal complex has occurred in the common ancestor of moles. However, ossification of the nasal bone has shifted late in the more terrestrial shrew mole. Among the lipotyphlans, sequence heterochrony shows no significant association with modules derived from developmental origins (that is, neural crest cells vs. mesoderm derived parts) or with those derived from ossification modes (that is, dermal vs. endochondral ossification). Conclusions The drastic acceleration of vomeronasal development in moles is most likely coupled with the increased importance of the rostrum for digging and its use as a specialized tactile surface, both fossorial adaptations. The late development of the nasal in shrew moles, a condition also displayed by hedgehogs and shrews, is suggested to be the result of an ecological reversal to terrestrial lifestyle and reduced functional importance of the rostrum. As an overall pattern in lipotyphlans, our results reject the hypothesis that ossification sequence heterochrony occurs in modular fashion when considering the developmental patterns of the skull. We suggest that shifts in the cranial ossification sequence are not evolutionarily constrained by developmental origins or mode of ossification

    Regulatory T Cells in Type 1 Autoimmune Pancreatitis

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    Autoimmune pancreatitis (AIP) is a newly recognized pancreatic disorder. Recently, International Consensus Diagnostic Criteria for AIP (ICDC) was published. In this ICDC, AIP was classified into Type 1 and Type 2. Patients with Type 1 AIP have several immunologic and histologic abnormalities specific to the disease, including increased levels of serum IgG4 and storiform fibrosis with infiltration of lymphocytes and IgG4-positive plasmacytes in the involved organs. Among the involved organs showing extrapancreatic lesions, the bile duct is the most common, exhibiting sclerosing cholangitis (IgG4-SC). However, the role of IgG4 is unclear. Recently, it has been reported that regulatory T cells (Tregs) are involved in both the development of various autoimmune diseases and the shift of B cells toward IgG4, producing plasmacytes. Our study showed that Tregs were increased in the pancreas with Type 1 AIP and IgG4-SC compared with control. In the patients with Type 1 AIP and IgG4-SC, the numbers of infiltrated Tregs were significantly positively correlated with IgG4-positive plasma cells. In Type 1 AIP, inducible costimulatory molecule (ICOS)+ and IL-10+ Tregs significantly increased compared with control groups. Our data suggest that increased quantities of ICOS+ Tregs may influence IgG4 production via IL-10 in Type 1 AIP

    A taxonomic reassessment of Rhinolophus rex Allen, 1923 and its allies (Chiroptera: Rhinolophidae)

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    This study integrates analyses of mitochondrial DNA sequences and morphological and acoustic data to re-evaluate the taxonomic status of Rhinolophus rex rex, R. r. paradoxolophus and R. schnitzleri throughout their distribution ranges. Based on a dense geographic sampling of specimens hitherto referred to these taxa and contrary to the current taxonomic view, our results indicate that all examined specimens of these taxa are representatives of a single, widely distributed and morphologically variable species, R. rex. The recognition of its geographic populations as different subspecies (R. r. rex and R. r. paradoxolophus) or distinct species (R. schnitzleri) based on morphological and acoustic data should be regarded as invalid. In the light of this revision, we also reassess the conservation status of R. rex against IUCN Red List criteria as Near Threatened
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