scholarly journals Iron-Rich Nanoparticles in Natural Aquatic Environments

Minerals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 287 ◽  
Author(s):  
Bjorn von der Heyden ◽  
Alakendra Roychoudhury ◽  
Satish Myneni
Keyword(s):  
Microscopic Investigation ◽  
The Body ◽  
Present Contribution ◽  
Natural Systems ◽  
Biogeochemical Models ◽  
Fe Nanoparticles ◽  
Nanoparticle Aggregates ◽  
Low Degrees ◽  
High Degree ◽  
Analytical Approaches

Naturally-occurring iron nanoparticles constitute a quantitatively-important and biogeochemically-active component of the broader Earth ecosystem. Yet detailed insights into their chemical speciation is sparse compared to the body of work conducted on engineered Fe nanoparticles. The present contribution briefly reviews the analytical approaches that can be used to characterize natural Fe nanoparticles, before detailing a dedicated synchrotron-based X-ray spectro-microscopic investigation into the speciation of suspended Fe nanoparticles collected from fluvial, marine, and lacustrine surface waters. Ferrous, ferric and magnetite classes of Fe nanoparticles (10–100 nm) were identified, and all three classes exhibited a high degree of heterogeneity in the local bonding environment around the Fe center. The heterogeneity is attributed to the possible presence of nanoparticle aggregates, and to the low degrees of crystallinity and ubiquitous presence of impurities (Al and organic moieties) in natural samples. This heterogeneity further precludes a spectroscopic distinction between the Fe nanoparticles and the larger sized Fe-rich particles that were evaluated. The presented results provide an important baseline for natural nanoparticle speciation in pristine aquatic systems, highlight the degree of inter-particle variability, which should be parameterized in future accurate biogeochemical models, and may inform predictions of the fate of released engineered Fe nanoparticles as they evolve and transform in natural systems.

scholarly journals Plant thermal tolerance: a global synthesis for future research

2020 ◽  
Author(s):  
Sonya Geange ◽  
Pieter Arnold ◽  
Alexandra Catling ◽  
Onoriode Coast ◽  
Alicia Cook ◽  
...  
Keyword(s):  
Cold Tolerance ◽  
Land Surface ◽  
Thermal Tolerance ◽  
Extreme Temperature ◽  
Critical Time ◽  
Functional Trait ◽  
The Body ◽  
Future Research ◽  
Biogeochemical Models ◽  
Analytical Approaches

<p>Extreme temperature events are increasing in frequency and intensity across the globe. These extremes, rather than averages, drive species evolution and determine survival by profoundly changing the structure and fluidity of cell membranes, altering enzyme function, and denaturing proteins. Given not only our dependence on agricultural crops and natural vegetation, but also the role of photosynthetic processes within the carbon and hydrological cycles, it is imperative to assess the state of our understanding of the potential impacts of extreme events on plants. Scaling responses from the molecular and organ level to ecosystem function is not without challenge however. There is vast literature on plant thermal tolerance research, but the body of literature is so large, the approaches so disparate and often siloed among disciplines, that research in this field risks floundering at a critical time. We conducted a systematic review of more than 21,500 studies spanning over 100 years of research that yielded almost 1,700 included studies on the tolerance of cultivated and wild land plants to both heat and cold. Our review indicates that most studies on thermal tolerance focus on the cold tolerance of cultivated species (52%) and only a trivial percentage of studies have considered both heat and cold tolerance of any given species (~5%). Combined heat and cold tolerance are important in areas where plants are exposed to extremes of both or may be in the future. This review illustrates the global distribution and concentrations of thermal tolerance studies and the diversity of thermal tolerance methods, ranging from molecular to biochemical, physiological and physical examinations, from transgenic model plants to agricultural and horticultural crops, to natural forest trees, shrubs, and grassland herbs. Critically, it also demonstrates that methods and metrics for assessing thermal tolerance are far from standardised, such that our potential to achieve mechanistic insight and compare across species and biomes is compromised. Without reconciling these issues, the scope for incorporating this critical ecological information into vegetation elements of land surface models may be limited. To aid this, we identify priorities for achieving efficient, reliable, and repeatable research across the spectrum of plant thermal tolerance. These priorities, including meta-analytical approaches and comparative experimental work, will not only further fundamental plant science, but will prove essential next steps if we are to integrate such diverse data on a critical plant functional trait into a usable metric within biogeochemical models.</p>

Relation of the Saccasa?khepa??k? Called S?ratthas?lin? to the Vinayavinicchaya??k? Called Vinayas?ratthasand?pan?

2018 ◽  
Vol 35 (1-2) ◽  
pp. 189-223
Author(s):  
Petra Kieffer-Pülz
Keyword(s):  
Thirteenth Century ◽  
Present Contribution ◽  
The Common ◽  
Literary Histories ◽  
High Degree ◽  
Parallel Texts

The present contribution suggests the common authorship of three P?li commentaries of the twelfth/thirteenth centuries CE, namely the Vinayavinicchaya??k? called Vinayas?ratthasand?pan? (less probably Vinayatthas?rasand?pan?), the Uttaravinicchaya??k? called L?natthappak?san?, and the Saccasa?khepa??k? called S?ratthas?lin?. The information collected from these three commentaries themselves and from P?li literary histories concerning these three texts leads to the second quarter of the thirteenth century CE as the period of their origination. The data from parallel texts explicitly stated to having been written by V?cissara Thera in the texts themselves render it possible to establish with a high degree of probability V?cissara Thera as their author.

Maiden Voyage

Nuncius ◽  
2011 ◽  
Vol 26 (1) ◽  
pp. 21-49
Author(s):  
Dario De Santis
Keyword(s):  
Eighteenth Century ◽  
Human Body ◽  
Scientific Community ◽  
Microscopic Investigation ◽  
The Body ◽  
Natural Phenomena ◽  
Scientific Debate

AbstractThe scientific debate which developed during the eighteenth century, proposed and diffused new theories on the generation not only within the scientific community. Microscopic investigation and various experimental campaigns fostered daring models attempting to unveil the natural phenomena from which life originates. Besides the famous scientific and philosophical works that marked the age, in the second part of the century two pamphlets appeared that well represent the importance of the querelle about embryological systems defining the concept of generation as a voyage within the human body. Lucina sine concubitu and Juno abortans, respectively published in England and in Germany between 1750 and 1760, narrate the odd and imaginary adventures of two doctors who are trying to interrupt and modify the embryos' journey towards the body of the mother.

The Shroud of Turin

1997 ◽  
Vol 9 (1) ◽  
pp. 121-140
Author(s):  
Thaddeus J. Trenn ◽  
Keyword(s):  
Body Image ◽  
Scientific Evidence ◽  
The Body ◽  
Religious Art ◽  
Satisfactory Explanation ◽  
Marshall Mcluhan ◽  
Modern Age ◽  
Shroud Of Turin ◽  
High Degree ◽  
As If

The Shroud of Turin, a linen cloth with but a faint image, continues to capture the interest of many people of diverse beliefs. Although the measured age of the cloth is relatively recent, other scientific findings indicate an earlier provenance. Any firm conclusions regarding the cloth's history remain premature. No satisfactory explanation has been found as yet for how the image on the cloth was produced structurally or stylistically. Iconographic evidence suggests that the image was the source of facial peculiarities found in early works of religious art. The body image bears a striking yet preternatural correlation with Scriptural accounts of wounds. Curiously, the image on the cloth functions as a photographic negative, exhibiting a high degree of resolution, as if the original were produced in pixels. Despite serious efforts to discover some artistic origin md medium, scientific evidence points in the direction that it was not produced by hands. If it is tme that the medium is the message, as Marshall McLuhan wrote, then the Turin Shroud may be a parable for the modern age.

Amino Acids Profiling in Fruit Juices by High Performance Liquid Chromatography: A Review

2020 ◽  
Vol 11 (SPL4) ◽  
pp. 2756-2767
Author(s):  
Vijaya Vemani ◽  
Mounika P ◽  
Poulami Das ◽  
Anand Kumar Tengli
Keyword(s):  
Amino Acids ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Amino Acid Content ◽  
Building Blocks ◽  
Fruit Juices ◽  
The Body ◽  
Total Amino Acid ◽  
Analytical Approaches

In the preservation of normal physiological functions, the building blocks of the body called amino acids play a crucial role. A number of valuable and nutritional phytoconstituents are contained in fruit juices, such as vitamins, minerals, microelements, organic acids, antioxidants, flavonoids, amino acids and other components. Due to the growing population and demand, the quality of fruit juices is decreasing. One of the unethical and harmful practices called adulteration or food fraudulence has been adopted by most food and beverage industries. The amino acids which is one of the most important phytochemicals of fruit and fruit juices which affects the organoleptic properties like color, odor, and taste of juices and also helps in authenticity process from governing bodies by providing total amino acid content. Consequently, the main aim of the present review work is to provide information regarding the importance of amino acids, how they are adulterated, the potential analytical approach to detected amino acids and which methods are generally accepted method by the food industries. According to the literature review, we presume that reverse phased high-performance liquid chromatography with pre-column derivatization was the most adopted method for quality checking due to its advantages over other old and recent analytical approaches like simple, rapid, cost-effective nature, less / no sample matrix effect with high sensitivity, accuracy, and precision.

scholarly journals Large elastic deformations of isotropic materials. I. Fundamental concepts

1948 ◽  
Vol 240 (822) ◽  
pp. 459-490 ◽  
Keyword(s):  
The Body ◽  
Elastic Behaviour ◽  
Stress And Strain ◽  
Elastic Deformations ◽  
Hooke’S Law ◽  
Widespread Agreement ◽  
Wide Range ◽  
Hooke's Law ◽  
High Degree

The mathematical theory of small elastic deformations has been developed to a high degree of sophistication on certain fundamental assumptions regarding the stress-strain relationships which are obeyed by the materials considered. The relationships taken are, in effect, a generalization of Hooke’s law— ut tensio, sic vis . The justification for these assumptions lies in the widespread agreement of experiment with the predictions of the theory and in the interpretation of the elastic behaviour of the materials in terms of their known structure. The same factors have contributed to our appreciation of the limitations of these assumptions. The principal problems, which the theory seeks to solve, are the determination of the deformation which a body undergoes and the distribution of stresses in it, when certain forces are applied to it, and when certain points of the body are subjected to specified displacements. These problems are always dealt with on the assumption that the generalization of Hooke’s law is obeyed by the material of the body and that the deformation is small, i.e. the change of length, in any linear element in the material, is small compared with the length of the element in the undeformed state. Apart from the fact that the generalization of Hooke’s law is obeyed accurately by a very wide range of materials, under a considerable variety of stress and strain conditions, it has the further advantage that it leads to a mathematically tractable theory.

scholarly journals CHANGES IN THE MUCOSA OF THE UTERINE POD IN CANCER OF THE VAGINAL PART AND CERVIX

2020 ◽  
Vol 5 (5) ◽  
pp. 410-435
Author(s):  
M. Mironov
Keyword(s):  
Mucous Membrane ◽  
Individual Case ◽  
The Body ◽  
Lymphoid Cells ◽  
Surface Layers ◽  
First Case ◽  
Epitheloid Cells ◽  
Deep Layers ◽  
High Degree ◽  
Sarcomatous Degeneration

Changes in the mucous membrane of the body of the uterus, accompanying cancer of the vaginal part and cervix, drew special attention after the work of Abel (see No. I), which appeared in 1888. The author studied the mucous membrane of the body of the uterus, taken from extirpated cases of 6 uterus for carcinoma portionis and in 1 case for carcinoma cervicis. "In all cases, the mucous membrane is dull," says the author (p. 279, 1. p.), To a high degree of alteration, while the mucous membrane of the cervix is ​​relatively insignificantly diseased. " These changes, as can be seen from the description of each individual case, concern both the gland and the intermediate tissue, and the first in all cases were multiplied and represented corkscrew gyrus; some of them were enlarged or contained ectases of the lateral walls and processes protruding into the lumen of the gland. Changes in the intermediate tissue in cases 1, 2 and 4 consisted in the multiplication of cells in deep layers, and here they had a short-spindle-shaped shape, small size and went in trains in different directions; in the surface layers, they were more or less round, much larger in size and resembled epitheloid cells. In addition, a nested infiltration with small, round cells (lymphoid cells?) Met in places. In the remaining 4 cases, the changes in the intermediate tissue, according to the author's description, were the same as usually in chronic inflammation (cases 5, 6 and 7) or almost absent (case 3). On the basis of these studies, the author comes to the conclusion that changes in the mucous membrane of the body of the uterus in cancer of the vaginal part and cervix have the character of sarcomatous degeneration, which in observed 1, 2 and 4-m, already reached a rather high degree of 4, in the rest, although it did not appear as sharp as especially in the first case, but nevertheless, these changes, according to the author, cannot be considered as inflammatory, but should be taken only as a more weak degree of the same sarcomatous degeneration, by analogy with the first.

Novel Non-Injection Approaches for Revealing and for Microscopic Investigation of the Microcirculatory Bed in Different Organs and Tissues

1997 ◽  
Vol 3 (S2) ◽  
pp. 327-328 ◽  
Author(s):  
N. Chilingaryan ◽  
A. Chilingaryan ◽  
M. Chilingaryan
Keyword(s):  
Vascular Endothelium ◽  
Microscopic Investigation ◽  
Extensive Study ◽  
Structural Elements ◽  
Selective Precipitation ◽  
Microcirculatory Bed ◽  
Clear Cut ◽  
Injection Methods ◽  
Pathological Material ◽  
High Degree

Certain disadvantages of traditional injection methods and difficulties arising during investigation of experimental and pathological material, limit the possibilities for extensive study of the microcirculatory bed (MCB). This has prompted the authors to develop new non-injection methods for revealing the MCB on histological sections by means of direct staining of the structural elements of the vessel wall. These methods are based on selective precipitation of the extra- or intracellular orthophosphates with ions of Zn, Cd, Co, Ca, Sr, and Pb in the vascular endothelium and smooth muscle cells. These methods (which we have called “histoangiological”) provide clear-cut contrast dyeing of the MCB in different organs and tissues as well as tumors in rat, cat,pig, dog, and in humans.In these methods, the reaction end product is lead sulfide which provides a high degree of contrast. Vessels and capillaries are detected due to precipitation of the deposit in the vascular endothelium.

scholarly journals Reasons for Staying: A Longitudinal Study of Work Conditions Predicting Social Workers’ Willingness to Stay in Their Organisation

2019 ◽  
Vol 50 (5) ◽  
pp. 1382-1400
Author(s):  
Wanja Astvik ◽  
Jonas Welander ◽  
Robert Larsson
Keyword(s):  
Social Workers ◽  
Social Services ◽  
Public Management ◽  
Work Conditions ◽  
Perceived Service Quality ◽  
Conflicting Demands ◽  
Intentions To Quit ◽  
One Year ◽  
Low Degrees ◽  
High Degree

Abstract Extensive staff turnover within the statutory social services is a serious problem in Sweden and in other European countries. This study examines which work conditions predict social workers’ willingness to stay in their organisation. A web-based questionnaire was used to gather data. The participating social workers responded to two questionnaires over a one-year period. To identify the social workers who wanted to stay and also remained in the organisation, the group ‘Stayers’ (n = 1,368) consisted of social workers who reported low intentions to quit at T1. The group ‘Leavers’ (n = 1,182) were social workers who had actually resigned at T2. The data were analysed using univariate and multivariate logistic regression analyses. The multivariate analysis shows that the work conditions that predicted staying in the organisation were low degrees of conflicting demands and quantitative demands, high degrees of openness and human resource orientation in the organisation and a high degree of perceived service quality. The results are discussed in relation to public management and managerial responsibility to create sustainable work conditions that facilitate the provision of good social services for citizens.

Systematic Literature Review on Narratives in Organizations: Research Issues and Avenues for Future Research

2016 ◽  
Vol 20 (4) ◽  
pp. 368-379 ◽  
Author(s):  
Shalini Sahni ◽  
Chandranshu Sinha
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Narrative Analysis ◽  
Personal Narratives ◽  
Past Research ◽  
The Body ◽  
Future Research ◽  
Organization Studies ◽  
Research Issues ◽  
Analytical Approaches

Narrative as a method is an interpretive approach of sharing individual experiences and beliefs that facilitates knowledge and generates human responses. The purpose of this study is to review the body of literature available using narratology in organization studies. This article employs a systematic literature review of 186 research articles in 94 identified journals from the year 1995 to 2014 that were subsequently evaluated for analysis. The review identifies five different approaches used by the narrative researchers across disciplines—content analysis (case study method), structural analysis, oral narratives and personal narratives, their contribution and spread in organizations. This article attempts to reinforce the significance of taking narratives as a methodology in organizations by providing a systematic overview of past research works in organizational settings. The study also summarizes the analytical approaches of narrative analysis used in 186 articles, which might underpin the qualitative research and provide some practical advice for those who wish to use narrative analysis in future.

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