Quantitation of nasal development in the early prenatal period using geometric morphometrics and MRI: a new insight into the critical period of Binder phenotype

2017 ◽  
Vol 37 (9) ◽  
pp. 907-915 ◽  
Author(s):  
Motoki Katsube ◽  
Shigehito Yamada ◽  
Reina Miyazaki ◽  
Yutaka Yamaguchi ◽  
Haruyuki Makishima ◽  
...  
Development ◽  
1960 ◽  
Vol 8 (2) ◽  
pp. 182-197
Author(s):  
Florence Moog ◽  
Evelina Ortiz

The epithelium of the duodenal mucosa of vertebrates is strikingly uniform. In all but the cyclostomes and a few fishes, the epithelium is made up of tall columnar absorbing cells, with mucus-producing goblet cells interspersed. The columnar cells have a high cytoplasmic/nuclear ratio, with the cytoplasm arranged into an apical zone containing a prominent Golgi apparatus, and a basal zone. The apical surface is featured by a sheet of microvilli that are extremely rich in alkaline phosphatase. The attainment of these characteristics has been shown to take place in a brief critical period, just before hatching in the chick embryo (Moog, 1950) and just before birth in the mouse (Moog, 1951), although in the latter animal a second period of phosphatase accumulation precedes weaning. The guinea-pig has now been added to this comparative series, because the protracted gestation period (about 67 days) might permit some further insight into the problems of duodenal differentiation.


2001 ◽  
Vol 9 (2) ◽  
pp. 19-50 ◽  
Author(s):  
Andreas F. Grein ◽  
C. Samuel Craig ◽  
Hirokazu Takada

Formulating a strategy to compete effectively in international markets is one of the major challenges a firm faces. The authors provide insight into how automobile firms devise strategies that respond to the conflicting pressures for local responsiveness and integration in the context of Western Europe, where Japanese automobile firms compete with European-based manufacturers. The authors develop a conceptual framework to test integration–responsiveness in terms of marketing-mix responses and market conditions, using data that cover four major European markets (73% of Western European sales) and a critical period in European integration. The findings indicate that Japanese firms are successfully pursuing standardization strategies rather than fully combining integration and responsiveness. These firms competitively adapt to limited differences between markets, and this strategy appears to be quite successful compared with the European firms’ strategies of combining integration and responsiveness. The European strategy appears to undermine the ability to respond to Japanese firms’ targeted competitive moves, despite the presence of significant barriers to Japanese exports. Whereas Japanese firms were able to maintain market share, European firms’ market shares decreased over the three-year period examined.


2021 ◽  
Vol 74 (2) ◽  
pp. 291-294
Author(s):  
Olexandr V. Tsyhykalo ◽  
Nataliia B. Kuzniak ◽  
Pavlo P. Perebyjnis ◽  
Svitlana I. Boitsaniuk ◽  
Iryna Ya. Tsvyntarna ◽  
...  

The aim: To determine the peculiarities of the morphometric parameters of suprahyoid region of the human prefetuses. Materials and methods: Thirty specimens of human prefetuses of 14.0-80.0 mm parietococcygeal length (PCL) (7-12 weeks of IUD) were studied using a complex of modern methods of morphological research. Results: On the basis of obtained digital indicators of the main morphometric parameters of human SHR in the dynamics of the prenatal period of IUD the critical periods of development of the region were clarified and mathematical functions that describe the normal course of organogenesis of SHR were created, which can be useful for creating diagnostic algorithms for the norm when carrying out prenatal diagnostics and monitoring the state of the fetus. It has been established that the 9-10th week of IUD is a critical period in the development of SHR, since during this time, intensive growth processes occur, which are manifested by a sharp change in the size of the organ, and this can lead to the appearance of variants of the structure and possible congenital defects of the SHR and the dental-maxillary apparatus in general. Conclusions: 1.Age-depended dynamics of changes in the anterior angle of the SHR shows an almost linear decrease in the angle by the end of the 9th week of IUD almost to 76°, after which it increases to almost 90° by the end of the 10th week. From the 11th week of the IUD, the anterior angle decreases again to 77 °, but begins to increase at the 12th week and by the end of the prefeal period. 2.The lateral length of SHR increases almost uniformly until the 9th week of IUD, during which its growth rate slows down. Starting from the end of the 10th week of IUD, this morphometric parameter begins to grow rapidly until the end of the prenatal period of ontogenesis. The growth rate of the lateral length of the SHR is described by the function: L lat = 1.1025 + 0.0015 x + 0.001 x2. 3.The width of the SHR from the 10th week of IUD begins to grow rapidly until the end of the prenatal period of development. The growth rate of the width of SHR is described by the function: W = 1.1025 + 0.0015 x + 0.001 x2. 4.Analysis of the age dynamics of the area of SHR demonstrates the exponential dependence on the age of the prefetuses, which is described by a mathematical function: A = 1,2452exp(0,0424x). Meanwhile, there is a slight slowdown in its growth rate at the 10th week of IUD with subsequent recovery of growth by the end of the prenatal period of ontogenesis. 5.The 9-10th week of IUD is a critical period in the development of SHR, since during this time, intensive growth processes occur, which are manifested by a sharp change in the size of the mandible.


2016 ◽  
Vol 116 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Randall M. Golovin ◽  
Nicholas J. Ward

Critical periods represent phases of development during which neuronal circuits and their responses can be readily shaped by stimuli. Experience-dependent plasticity that occurs within these critical periods can be influenced in many ways; however, Shepard et al. ( J Neurosci 35: 2432–2437, 2015) recently singled out norepinephrine as an essential driver of this plasticity within the auditory cortex. This work provides novel insight into the mechanisms of critical period plasticity and challenges previous conceptions that a functional redundancy exists between noradrenergic and cholinergic influences on cortical plasticity.


Author(s):  
Michael C. Hawkins

This book offers a concise, revealing, and analytically penetrating view of a critical period in Philippine history. The book examines Moro (Filipino Muslim) contributions to the Philippine exhibit at the St. Louis World's Fair in 1904, providing insight into this fascinating and previously overlooked historical episode. By reviving and contextualizing Moro participation in the exposition, the book challenges the typical manifestations of empire drawn from the fair and delivers a nuanced and textured vision of the nature of American imperial discourse. The book argues that the Moro display provided a distinctive liminal space in the dialectical relationship between civilization and savagery at the fair. The Moros offered a transcultural bridge. Through their official yet nondescript designation as “semi-civilized,” they undermined and mediated the various binaries structuring the exposition. As the book demonstrates, this mediation represented an unexpectedly welcomed challenge to the binary logic and discomfort of the display. As the book shows, the Moro display was collaborative, and the Moros exercised unexpected agency by negotiating how the display was both structured and interpreted by the public. Fairgoers were actively seeking an extraordinary experience. Exhibit organizers framed it, but ultimately the Moros provided it. And therein lay a tremendous amount of power.


Author(s):  
David Kohnen

This chapter by David Kohnen examines the Allied response to the initial German submarine operations in the Indian Ocean during the Second World War. Roughly forty German submarines sailed for East Asian waters after 1942; U-188 was among the few to navigate the Allied gauntlet in the Atlantic to reach the Indian Ocean. Only three German submarines, including U-188, returned to Europe from operations in the Indian Ocean before the Allied victory in May of 1945. The discussions between key British and American commanders regarding the presence of German submarines in the Indian Ocean provide unique insight into the operations and intelligence organizations of the Admiralty and Navy Department and are examined in detail. The chapter also looks at the Allied submarine tracking rooms, which assisted the Special Operations Executive and Office of Strategic Services in the capture of the skipper of U-188 – thereby securing information on the Imperial Japanese during a critical period in the closing months of the Second World War.


2021 ◽  
Author(s):  
Ola Demkowicz ◽  
Emma Ashworth ◽  
Alisha O'Neill ◽  
Terry Hanley ◽  
Kirsty Pert

Abstract Background and Aims: For older adolescents, the COVID-19 pandemic and associated UK restrictions arrived during a critical period in the transition to adulthood. Early research exploring impact of the pandemic paints a picture of worsened adolescent wellbeing and mental health. We explore the subjective experiences of 16- to 19-year-olds during the first UK lockdown, with an emphasis on wellbeing and coping, in order to complement emergent quantitative evidence and inform strategies and provision for support. Methods: In May 2020, we invited UK-based 16- to 19-year-olds to share their experiences of the initial lockdown for ‘[project name redacted for blinded peer review]’. 109 participants took part, submitting anonymous written accounts via an online portal. We used inductive reflexive thematic analysis to develop rich experiential themes.Findings: We constructed seven main themes: heightened emotionality; feelings of loss, change, and uncertainty; recognising the value of self-care; efforts to think positively; opportunities for relief, growth, and development; the importance of togetherness; and frustration with government and media. Implications: Findings highlight the multifaceted nature of adolescents’ lockdown experiences, and offer insight into emotional impact and new concerns as well as the value placed on self-care and staying connected. We offer directions for supporting adolescents as pandemic consequences continue.


1966 ◽  
Vol 24 ◽  
pp. 322-330
Author(s):  
A. Beer

The investigations which I should like to summarize in this paper concern recent photo-electric luminosity determinations of O and B stars. Their final aim has been the derivation of new stellar distances, and some insight into certain patterns of galactic structure.


1984 ◽  
Vol 75 ◽  
pp. 461-469 ◽  
Author(s):  
Robert W. Hart

ABSTRACTThis paper models maximum entropy configurations of idealized gravitational ring systems. Such configurations are of interest because systems generally evolve toward an ultimate state of maximum randomness. For simplicity, attention is confined to ultimate states for which interparticle interactions are no longer of first order importance. The planets, in their orbits about the sun, are one example of such a ring system. The extent to which the present approximation yields insight into ring systems such as Saturn's is explored briefly.


Author(s):  
D. F. Blake ◽  
L. F. Allard ◽  
D. R. Peacor

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.


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