83 research outputs found
Locomotor preferences in terrestrial vertebrates: An online crowdsourcing approach to data collection
Understanding how animals move within their environment is a burgeoning field of research. Despite
this, relatively basic data, such as the locomotor speeds that animals choose to walk at in the wild,
are sparse. If animals choose to walk with dynamic similarity, they will move at equal dimensionless
speeds, represented by Froude number (Fr). Fr may be interpreted from simple limb kinematics
obtained from video data. Here, using Internet videos, limb kinematics were measured in 112 bird and
mammal species weighing between 0.61 and 5400 kg. This novel method of data collection enabled
the determination of kinematics for animals walking at their self-selected speeds without the need for
exhaustive fieldwork. At larger sizes, both birds and mammals prefer to walk at slower relative speeds
and relative stride frequencies, as preferred Fr decreased in larger species, indicating that Fr may not be
a good predictor of preferred locomotor speeds. This may result from the observation that the minimum
cost of transport is approached at lower Fr in larger species. Birds walk with higher duty factors, lower
stride frequencies and longer stance times compared to mammals at self-selected speeds. The trend
towards lower preferred Fr is also apparent in extinct vertebrate species
Adverse Effect of Nano-Silicon Dioxide on Lung Function of Rats with or without Ovalbumin Immunization
BACKGROUND: The great advances of nanomaterials have brought out broad important applications, but their possible nanotoxicity and risks have not been fully understood. It is confirmed that exposure of environmental particulate matter (PM), especially ultrafine PM, are responsible for many lung function impairment and exacerbation of pre-existing lung diseases. However, the adverse effect of nanoparticles on allergic asthma is seldom investigated and the mechanism remains undefined. For the first time, this work investigates the relationship between allergic asthma and nanosized silicon dioxide (nano-SiOâ). METHODOLOGY/PRINCIPAL FINDINGS: Ovalbumin (OVA)-treated and saline-treated control rats were daily intratracheally administered 0.1 ml of 0, 40 and 80 ”g/ml nano-SiOâ solutions, respectively for 30 days. Increased nano-SiOâ exposure results in adverse changes on inspiratory and expiratory resistance (Ri and Re), but shows insignificant effect on rat lung dynamic compliance (Cldyn). Lung histological observation reveals obvious airway remodeling in 80 ”g/ml nano-SiOâ-introduced saline and OVA groups, but the latter is worse. Additionally, increased nano-SiOâ exposure also leads to more severe inflammation. With increasing nano-SiOâ exposure, IL-4 in lung homogenate increases and IFN-Îł shows a reverse but insignificant change. Moreover, at a same nano-SiOâ exposure concentration, OVA-treated rats exhibit higher (significant) IL-4 and lower (not significant) IFN-Îł compared with the saline-treated rats. The percentages of eosinophil display an unexpected result, in which higher exposure results lower eosinophil percentages. CONCLUSIONS/SIGNIFICANCE: This was a preliminary study which for the first time involved the effect of nano-SiOâ to OVA induced rat asthma model. The results suggested that intratracheal administration of nano-SiOâ could lead to the airway hyperresponsiveness (AHR) and the airway remolding with or without OVA immunization. This occurrence may be due to the Th1/Th2 cytokine imbalance accelerated by the nano-SiOâ through increasing the tissue IL-4 production
The Servant Leadership Survey: Development and Validation of a Multidimensional Measure
Purpose:
The purpose of this paper is to describe the development and validation of a multi-dimensional instrument to measure servant leadership.
Design/Methodology/Approach
Based on an extensive literature review and expert judgment, 99 items were formulated. In three steps, using eight samples totaling 1571 persons from The Netherlands and the UK with a diverse occupational background, a combined exploratory and confirmatory factor analysis approach was used. This was followed by an analysis of the criterion-related validity.
Findings:
The final result is an eight-dimensional measure of 30 items: the eight dimensions being: standing back, forgiveness, courage, empowerment, accountability, authenticity, humility, and stewardship. The internal consistency of the subscales is good. The results show that the Servant Leadership Survey (SLS) has convergent validity with other leadership measures, and also adds unique elements to the leadership field. Evidence for criterion-related validity came from studies relating the eight dimensions to well-being and performance.
Implications:
With this survey, a valid and reliable instrument to measure the essential elements of servant leadership has been introduced.
Originality/Value
The SLS is the first measure where the underlying factor structure was developed and confirmed across several field studies in two countries. It can be used in future studies to test the underlying premises of servant leadership theory. The SLS provides a clear picture of the key servant leadership qualities and shows where improvements can be made on the individual and organizational level; as such, it may also offer a valuable starting point for training and leadership development
Severe traumatic injury during long duration spaceflight: Light years beyond ATLS
Traumatic injury strikes unexpectedly among the healthiest members of the human population, and has been an inevitable companion of exploration throughout history. In space flight beyond the Earth's orbit, NASA considers trauma to be the highest level of concern regarding the probable incidence versus impact on mission and health. Because of limited resources, medical care will have to focus on the conditions most likely to occur, as well as those with the most significant impact on the crew and mission. Although the relative risk of disabling injuries is significantly higher than traumatic deaths on earth, either issue would have catastrophic implications during space flight. As a result this review focuses on serious life-threatening injuries during space flight as determined by a NASA consensus conference attended by experts in all aspects of injury and space flight
Excess-entropy scaling in supercooled binary mixtures
Supercooled liquids near the glass transition show remarkable non-Arrhenius transport phenomena, whose origin is yet to be clarified. Here, the authors use GPU molecular dynamics simulations for various binary mixtures in the supercooled regime to show the validity of a quasiuniversal excess-entropy scaling relation for viscosity and diffusion
Vampires in the village Ćœrnovo on the island of KorÄula: following an archival document from the 18th century
SrediĆĄnja tema rada usmjerena je na raĆĄÄlambu spisa pohranjenog u DrĆŸavnom arhivu u Mlecima (fond: Capi del Consiglio deâ Dieci: Lettere di Rettori e di altre cariche) koji se odnosi na dogaÄaj iz 1748. godine u korÄulanskom selu Ćœrnovo, kada su mjeĆĄtani â vjerujuÄi da su se pojavili vampiri â oskvrnuli nekoliko mjesnih grobova. U radu se podrobno iznose osnovni podaci iz spisa te reÄeni dogaÄaj analizira u ĆĄirem druĆĄtvenom kontekstu i prate se lokalna vjerovanja.The main interest of this essay is the analysis of the document from the State Archive in Venice (file: Capi del Consiglio deâ Dieci: Lettere di Rettori e di altre cariche) which is connected with the episode from 1748 when the inhabitants of the village Ćœrnove on the island of KorÄula in Croatia opened tombs on the local cemetery in the fear of the vampires treating.
This essay try to show some social circumstances connected with this event as well as a local vernacular tradition concerning superstitions
International Consensus Statement on Rhinology and Allergy: Rhinosinusitis
Background: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICARâRS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICARâRSâ2021 as well as updates to the original 140 topics. This executive summary consolidates the evidenceâbased findings of the document. Methods: ICARâRS presents over 180 topics in the forms of evidenceâbased reviews with recommendations (EBRRs), evidenceâbased reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary. Results: ICARâRSâ2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidenceâbased management algorithm is provided. Conclusion: This ICARâRSâ2021 executive summary provides a compilation of the evidenceâbased recommendations for medical and surgical treatment of the most common forms of RS
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