scholarly journals An evidence-based 3D reconstruction of Asteroxylon mackiei the most complex plant preserved from the Rhynie chert

2021 ◽  
Author(s):  
Alexander J Hetherington ◽  
Siobhán L Bridson ◽  
Anna Lee Jones ◽  
Hagen Hass ◽  
Hans Kerp ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Early Life ◽  
3D Structure ◽  
Terrestrial Ecosystem ◽  
The Body ◽  
Evidence Based ◽  
Ancestral State ◽  
Leafy Shoot ◽  
Rhynie Chert ◽  
Development And Evolution

The 407-million-year-old Rhynie chert preserves the earliest terrestrial ecosystem and informs our understanding of early life on land. However, our knowledge of the 3D structure, and development of these plants is still rudimentary. Here we used digital 3D reconstruction techniques to produce the first complete reconstruction of the lycopsid Asteroxylon mackiei, the most complex plant in the Rhynie chert. The reconstruction reveals the organisation of the three distinct axes types — leafy shoot axes, root-bearing axes and rooting axes — in the body plan. Combining this reconstruction with developmental data from fossilised meristems, we demonstrate that the A. mackiei rooting axis — a transitional lycophyte organ between the rootless ancestral state and true roots — developed from root-bearing axes by anisotomous dichotomy. Our discovery demonstrates how this unique organ developed, and highlights the value of evidence-based reconstructions for understanding the development and evolution of the first complex plants on Earth.

scholarly journals An evidence-based 3D reconstruction of Asteroxylon mackiei, the most complex plant preserved from the Rhynie chert

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alexander J Hetherington ◽  
Siobhán L Bridson ◽  
Anna Lee Jones ◽  
Hagen Hass ◽  
Hans Kerp ◽  
...  
Keyword(s):  
3D Reconstruction ◽  
Vascular Plants ◽  
3D Structure ◽  
Terrestrial Ecosystem ◽  
The Body ◽  
Evidence Based ◽  
Ancestral State ◽  
Early Devonian ◽  
Rhynie Chert ◽  
Development And Evolution

The Early Devonian Rhynie chert preserves the earliest terrestrial ecosystem and informs our understanding of early life on land. However, our knowledge of the 3D structure, and development of these plants is still rudimentary. Here we used digital 3D reconstruction techniques to produce the first well-evidenced reconstruction of the structure and development of the rooting system of the lycopsid Asteroxylon mackiei, the most complex plant in the Rhynie chert. The reconstruction reveals the organisation of the three distinct axis types – leafy shoot axes, root-bearing axes, and rooting axes – in the body plan. Combining this reconstruction with developmental data from fossilised meristems, we demonstrate that the A. mackiei rooting axis – a transitional lycophyte organ between the rootless ancestral state and true roots – developed from root-bearing axes by anisotomous dichotomy. Our discovery demonstrates how this unique organ developed and highlights the value of evidence-based reconstructions for understanding the development and evolution of the first complex vascular plants on Earth.

scholarly journals Terrestrial invertebrates in the Rhynie chert ecosystem

2017 ◽  
Vol 373 (1739) ◽  
pp. 20160493 ◽  
Author(s):  
Jason A. Dunlop ◽  
Russell J. Garwood
Keyword(s):  
Early Life ◽  
Hot Springs ◽  
Terrestrial Ecosystem ◽  
Early Devonian ◽  
Male And Female ◽  
Terrestrial Invertebrates ◽  
Plant Parasitism ◽  
Liquid Feeding ◽  
Rhynie Chert ◽  
Nematode Worm

The Early Devonian Rhynie and Windyfield cherts remain a key locality for understanding early life and ecology on land. They host the oldest unequivocal nematode worm (Nematoda), which may also offer the earliest evidence for herbivory via plant parasitism. The trigonotarbids (Arachnida: Trigonotarbida) preserve the oldest book lungs and were probably predators that practiced liquid feeding. The oldest mites (Arachnida: Acariformes) are represented by taxa which include mycophages and predators on nematodes today. The earliest harvestman (Arachnida: Opiliones) includes the first preserved tracheae, and male and female genitalia. Myriapods are represented by a scutigeromorph centipede (Chilopoda: Scutigeromorpha), probably a cursorial predator on the substrate, and a putative millipede (Diplopoda). The oldest springtails (Hexapoda: Collembola) were probably mycophages, and another hexapod of uncertain affinities preserves a gut infill of phytodebris. The first true insects (Hexapoda: Insecta) are represented by a species known from chewing (non-carnivorous?) mandibles. Coprolites also provide insights into diet, and we challenge previous assumptions that several taxa were spore-feeders. Rhynie appears to preserve a largely intact community of terrestrial animals, although some expected groups are absent. The known fossils are (ecologically) consistent with at least part of the fauna found around modern Icelandic hot springs. This article is part of a discussion meeting issue ‘The Rhynie cherts: our earliest terrestrial ecosystem revisited’.

Detection, Averaging, and 3D Reconstruction of Biological Specimens on Hypercubes (Transputer-based) Computers

1990 ◽  
Vol 48 (1) ◽  
pp. 454-455
Author(s):  
Jose-Maria Carazo ◽  
I. Benavides ◽  
S. Marco ◽  
J.L. Carrascosa ◽  
E.L. Zapata
Keyword(s):  
3D Reconstruction ◽  
3D Structure ◽  
Three Dimensional ◽  
Software Tools ◽  
Mapping Method ◽  
Computer Architectures ◽  
Parallel Computer ◽  
Reconstruction Process ◽  
Computing Power ◽  
Order Of Magnitude

Obtaining the three-dimensional (3D) structure of negatively stained biological specimens at a resolution of, typically, 2 - 4 nm is becoming a relatively common practice in an increasing number of laboratories. A combination of new conceptual approaches, new software tools, and faster computers have made this situation possible. However, all these 3D reconstruction processes are quite computer intensive, and the middle term future is full of suggestions entailing an even greater need of computing power. Up to now all published 3D reconstructions in this field have been performed on conventional (sequential) computers, but it is a fact that new parallel computer architectures represent the potential of order-of-magnitude increases in computing power and should, therefore, be considered for their possible application in the most computing intensive tasks.We have studied both shared-memory-based computer architectures, like the BBN Butterfly, and local-memory-based architectures, mainly hypercubes implemented on transputers, where we have used the algorithmic mapping method proposed by Zapata el at. In this work we have developed the basic software tools needed to obtain a 3D reconstruction from non-crystalline specimens (“single particles”) using the so-called Random Conical Tilt Series Method. We start from a pair of images presenting the same field, first tilted (by ≃55°) and then untilted. It is then assumed that we can supply the system with the image of the particle we are looking for (ideally, a 2D average from a previous study) and with a matrix describing the geometrical relationships between the tilted and untilted fields (this step is now accomplished by interactively marking a few pairs of corresponding features in the two fields). From here on the 3D reconstruction process may be run automatically.

Doctor of Nursing Practice: Integrating Theory, Research, and Evidence-Based Practice

2013 ◽  
Vol 6 (1) ◽  
pp. 4-8 ◽  
Author(s):  
Bridget R. Roberts
Keyword(s):  
Nursing Practice ◽  
Evidence Based Practice ◽  
Strong Relationship ◽  
The Body ◽  
Evidence Based ◽  
Advanced Practice ◽  
Nursing Knowledge ◽  
Doctor Of Nursing Practice ◽  
Practice Nurses ◽  
Theory Research

A strong relationship exists between theory, research, and evidence-based practice; and these three entities are necessary to guide practice and contribute to the body of nursing knowledge. Doctor of nursing practice graduates can serve as leaders as they enter into their respective clinical practice areas. Through education of peers, along with translation and evaluation of current theoretical literature and empirical data, these advanced practice nurses can positively influence nursing practice and patient care.

Abstract WP282: Protecting Stroke Patients from Aspiration and Mortality through a Bedside Aspiration Screen

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Edith Matesic
Keyword(s):  
Organizational Learning ◽  
Aspiration Pneumonia ◽  
The Body ◽  
Kappa Statistics ◽  
Evidence Based ◽  
Stroke Patients ◽  
Rater Reliability ◽  
Stroke Treatment ◽  
Risk Of Death ◽  
The Impact

Background: Stroke patients initially experience dysphagia approximately 42-76% of the time, putting them at high risk for developing aspiration pneumonia and increasing the risk of death threefold in the first 30 days following onset of the condition. Interventions to identify risk for aspiration pneumonia are key to reducing mortality in hospitalized patients. However, no generally recognized bedside aspiration screen exists, and few have been rigorously tested. The Edith-Huhn-Matesic Bedside Aspiration Screen (EHMBAS) TM was developed as an evidence-based RN bedside aspiration screening protocol. Purpose: This study analyzed the sensitivity and inter-rater reliability of EHMBAS TM , assessed the efficacy of training methods, evaluated patient feedback, and looked at the impact of organizational learning. Methods: RNs were trained to apply the EHMBAS TM . An evaluation study assessed the sensitivity, specificity and predictability of the screen to detect aspiration in the stroke population study group. Cohen’s Kappa statistics was applied to test inter-rater reliability. Pre- and post-implementation Likert surveys examined patient and staff satisfaction on the education plan and screening process, respectively. Lastly, an analysis of organizational learning examined whether changes enhanced adherence to screening requirements. Results: Results showed that the EHMBAS TM demonstrated strong validity (94% sensitivity) and high inter-rater reliability (Kappa = .92, p<.001). Pre- and post- staff training survey results demonstrated a significant positive change in knowledge gained, feelings of preparedness, and satisfaction with teaching methods. Further, 92.3% of patients surveyed had positive screening experiences. The hospital received Silver recognition from The American Heart Association for following stroke treatment guidelines 85% of the time for at least 12 months, demonstrating the positive impact of the protocol on organizational change. Conclusions: This study contributes to the body of work aimed at establishing a reliable evidence-based, bedside aspiration screen. Patient safety is enhanced, because screen results help determine when patients can safely receive medication and nutrition by mouth.

The physical basis of mollusk shell chiral coiling

2021 ◽  
Vol 118 (48) ◽  
pp. e2109210118
Author(s):  
Régis Chirat ◽  
Alain Goriely ◽  
Derek E. Moulton
Keyword(s):  
Mathematical Model ◽  
The Body ◽  
Symmetric Body ◽  
Model Organisms ◽  
Physical Interaction ◽  
Mechanical Forces ◽  
Hard Shell ◽  
Left Right Asymmetry ◽  
Development And Evolution ◽  
Mollusk Shell

Snails are model organisms for studying the genetic, molecular, and developmental bases of left–right asymmetry in Bilateria. However, the development of their typical helicospiral shell, present for the last 540 million years in environments as different as the abyss or our gardens, remains poorly understood. Conversely, ammonites typically have a bilaterally symmetric, planispiraly coiled shell, with only 1% of 3,000 genera displaying either a helicospiral or a meandering asymmetric shell. A comparative analysis suggests that the development of chiral shells in these mollusks is different and that, unlike snails, ammonites with asymmetric shells probably had a bilaterally symmetric body diagnostic of cephalopods. We propose a mathematical model for the growth of shells, taking into account the physical interaction during development between the soft mollusk body and its hard shell. Our model shows that a growth mismatch between the secreted shell tube and a bilaterally symmetric body in ammonites can generate mechanical forces that are balanced by a twist of the body, breaking shell symmetry. In gastropods, where a twist is intrinsic to the body, the same model predicts that helicospiral shells are the most likely shell forms. Our model explains a large diversity of forms and shows that, although molluscan shells are incrementally secreted at their opening, the path followed by the shell edge and the resulting form are partly governed by the mechanics of the body inside the shell, a perspective that explains many aspects of their development and evolution.

The supine position of postnatal human infants

2009 ◽  
Vol 10 (2) ◽  
pp. 252-269 ◽  
Author(s):  
Hideko Takeshita ◽  
Masako Myowa-Yamakoshi ◽  
Satoshi Hirata
Keyword(s):  
Supine Position ◽  
Postnatal Period ◽  
The Body ◽  
Body Parts ◽  
Human Infants ◽  
Face To Face ◽  
Developmental Continuity ◽  
Exploratory Movements ◽  
Locomotor Ability ◽  
Development And Evolution

In this review, we discuss the implications of placing an infant in the supine position with respect to human cognitive development and evolution. When human infants are born, they are relatively large and immature in terms of postural and locomotor ability as compared with their closest relatives, the great apes. Hence, human mothers seemingly adopt a novel pattern of caring for their large and heavy infants, i.e., placing their infants in the supine position; this promotes face-to-face communication with their infants. Moreover, infants in the supine position can interact with other nearby individuals in the same manner from an early age. In addition, the infants can also explore their own body parts and/or objects with their hands since the hands are not required to support the body and are therefore, free to move. These activities are considered to be fundamental to the early development of human social and nonsocial cognition, including knowledge of self, in the first six months after birth. Further, developmental continuity in the voluntary exploratory movements in the prenatal period (in utero) to the early postnatal period is also discussed.

scholarly journals 335 The Gut-Lung Axis: The Human Perspective

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 69-70
Author(s):  
Michael Surette
Keyword(s):  
Respiratory Tract ◽  
Early Life ◽  
Inflammatory Diseases ◽  
Chronic Inflammatory Disease ◽  
The Body ◽  
Upper Respiratory Tract ◽  
Targeted Interventions ◽  
Susceptibility To Infection ◽  
Airway Diseases ◽  
Asthma And Allergy

Abstract The human gastrointestinal tract is the largest immune organ in the body and consequently influences the overall immune state of all body sites. The gut also harbors the largest proportion of the microbiome. In early life, the maturation of the microbiome and immune system are closely entangled, forming a homeostatic system that imparts individuality and stability to the host microbiome. It is now well established that factors that affect early life gut microbiota modulate susceptibility to chronic inflammatory diseases, including airway diseases such as asthma and allergy. Despite this global influence of the gut on immune response in the lungs, local microbiome-immune interactions also shape the response and susceptibility to disease in the airways. The upper respiratory tract and lung microbiomes also contribute to acute and chronic airway diseases. Modulating the gut-lung axis as well as respiratory tract through microbiome-targeted interventions to promote health and reduce susceptibility to infection and chronic inflammatory disease may represent an effective strategy, particularly in early and late life.

scholarly journals LIVE BIRTHS AND STILLBIRTHS – QUESTIONS OF FORENSIC SCIENCE AND RADIOLOGY: CASES FROM EXPERT PRACTICE

2021 ◽  
Author(s):  
Yulia V. Chumakova ◽  
Sofia E. Dubrova ◽  
Natalia S. Muranova ◽  
Olga M. Popova ◽  
Vladimir A. Klevno
Keyword(s):  
Live Birth ◽  
The Body ◽  
Evidence Based ◽  
Case Presentation ◽  
X Ray ◽  
Congenital Deformities ◽  
Medical Study ◽  
Private House ◽  
Life Tests ◽  
History Of

Introduction: The article deals with the criteria, forensic and radiological "life tests", difficulties in assessing the results of live birth and stillbirth of the fetus. An excursion into the history of the development of X-ray, including pre-sectional, examination of the corpses of newborns is made. Cases from the practice of two corpses of newborns which underwent pre-section computed tomography are presented. Case presentation: Case № 1: examination of the corpse of a baby found in a cardboard box on the unheated terrace of a private house after a secret self-birth. Case № 2: examination of the corpse of an infant with massive injuries and the division of the body into two fragments, found on a sorting tape in the premises of the waste sorting shop. Conclusion: Postmortem CT of newborn corpses was an evidence-based and visual addition to the traditional forensic medical study, which allowed even at the pre-dissection stage to speak about the maturity of fetuses, to identify injuries and anatomical variants of the structure, to refute the presence of congenital deformities; to establish and record evidence-based CT signs of live birth and stillbirth.

scholarly journals Monitoring of the load regime applied on the osseointegrated fixation of a trans-femoral amputee: A tool for evidence-based practice

2008 ◽  
Vol 32 (1) ◽  
pp. 68-78 ◽  
Author(s):  
Laurent Frossard ◽  
Nathan Stevenson ◽  
James Smeathers ◽  
Eva Häggström ◽  
Kerstin Hagberg ◽  
...  
Keyword(s):  
Performance Indicators ◽  
Daily Living ◽  
Evidence Based Practice ◽  
Maximum Load ◽  
The Body ◽  
Evidence Based ◽  
Data Logger ◽  
Actual Usage ◽  
Load Regime ◽  
User Friendly

This study aimed to provide a description of the continuous recording of the true load regime experienced during daily living by the abutment of a trans-femoral amputee fitted with an osseointegrated fixation. The specific objectives: (i) To present an apparatus and a procedure allowing recording of the load regime, and (ii) an example of the raw data and six performance indicators of the usage of the prosthesis obtained with this method. A subject was monitored for a period of 5 hours as he went about his daily activities. The load regime was directly measured and recorded using a commercial transducer and data logger. The overall load profile presented alternative periods of variable length of inactivity (64%) and activity (36%), respectively. The maximum load applied on the mediolateral, anteroposterior and the long axes represented 21%, 21% and 120% of the body weight, respectively. The anteroposterior, mediolateral and long components of the impulse were 395 kN.s, 359 kN.s and 2,323 kN.s, respectively. The amputee generated a total of 2312 gait cycles of the prosthetic leg, giving an approximate overall cadence of 8 stride/min. Preliminary outcomes indicated that the proposed method was an improvement on the current techniques as it provided the true loading and actual usage of the prosthesis during daily living. This study is a stepping stone in the development of future affordable, on-board and user-friendly load recording systems that can be used in evidence-based practice.

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