scholarly journals First empirical evidence of naturally occurring androgenesis in vertebrates

2017 ◽  
Vol 4 (5) ◽  
pp. 170200 ◽  
Author(s):  
Miguel Morgado-Santos ◽  
Sara Carona ◽  
Luís Vicente ◽  
Maria João Collares-Pereira

Androgenesis among vertebrates is considered a rare phenomenon, with some cases reported so far, but linked to experiments involving gamete manipulation (artificial androgenesis). Herein, we report the first empirical evidence of the natural occurrence of spontaneous androgenesis in a vertebrate, the Squalius alburnoides allopolyploid complex. A genetically screened random sample of a natural population was allowed to reproduce in an isolated pond without any human interference, and the viable offspring obtained was later analysed for paternity. Both nuclear and mitochondrial markers showed that the only allodiploid fish found among all the allotriploid offspring was androgenetically produced by an allodiploid male. This specimen had no female nuclear genomic input, and the sequence of the mitochondrial fragment examined differed from that of the male progenitor, matching one of the parental females available in the pond, probably the mother. The possible role of androgenesis in the reproductive dynamics of this highly successful vertebrate complex is discussed.

2004 ◽  
Vol 48 (8) ◽  
pp. 3196-3199 ◽  
Author(s):  
Sabrina Krief ◽  
Marie-Thérèse Martin ◽  
Philippe Grellier ◽  
John Kasenene ◽  
Thierry Sévenet

ABSTRACT Following a veterinary and behavioral survey of chimpanzees from a natural population in Uganda, leaf samples of Trichilia rubescens were collected because of the unusual method of ingestion observed. The methanolic crude extract of T. rubescens leaves exhibited significant antimalarial activity in vitro. Bioassay-directed fractionation provided two new limonoids, trichirubines A and B. A greater understanding of the role of secondary compounds in the primate diet may be helpful in recovering naturally occurring compounds of medicinal significance for human medicine.


Author(s):  
David R. Veblen

Extended defects and interfaces control many processes in rock-forming minerals, from chemical reactions to rock deformation. In many cases, it is not the average structure of a defect or interface that is most important, but rather the structure of defect terminations or offsets in an interface. One of the major thrusts of high-resolution electron microscopy in the earth sciences has been to identify the role of defect fine structures in reactions and to determine the structures of such features. This paper will review studies using HREM and image simulations to determine the structures of defects in silicate and oxide minerals and present several examples of the role of defects in mineral chemical reactions. In some cases, the geological occurrence can be used to constrain the diffusional properties of defects.The simplest reactions in minerals involve exsolution (precipitation) of one mineral from another with a similar crystal structure, and pyroxenes (single-chain silicates) provide a good example. Although conventional TEM studies have led to a basic understanding of this sort of phase separation in pyroxenes via spinodal decomposition or nucleation and growth, HREM has provided a much more detailed appreciation of the processes involved.


2017 ◽  
Vol 1 (2) ◽  
pp. 152-170
Author(s):  
Ahmad Ubaidillah

Throughout my experience in tracking down and reading books on faith-based economics, in this case Islam, there are no books that specifically list the title of "Islamic economics". If there is, it is only initiated or introduced. Most books coming down to us still use the titles starting with the word, for example, system, concept, principle, or the doctrine of Islamic economics. Why do the authors of the book Islamic economics seem not dared to give his book title with label "science"? I presume that Islamic economics has not been considered as a science. In building a science, methodology is required. Islamic Economics also requires a well-established methodology to build the foundation of science. The study answers questions; how is methodology which is offered by Muhammad Akram Khan to build Islamic economics. The method used in this research is the study of literature with qualitative approach.The result of study concludes that Khan offers methodology of Islamic economics, if summarized, written as follows: First, Islamic economics uses a framework derived from the texts of divinity (revelation). Second, Islamic economics uses the inductive method, which gives witness to the truth or falsity assumptions and predictions about the two criteria of rationality and empirical evidence. Third, Islamic economy is built on ethical values ​​such as justice, virtue, moderation, sacrifice, caring for others, in the analysis, as behavioral parameters. Fourth, Islamic economics is a normative discipline. Islamic Economics investigates ways and means to change the existing economy with Islamic economy. Fifth, Islamic economics ask different questions with conventional economics. Its attention is on welfare (falah) human and creating social and institutional conditions that maximize falah in society. Clearly, Islamic economics strongly supports research programs that help maximize falah. Furthermore, Khan elaborates several issues related to the methodology that often appears in the forum of Islamic economists. There are some problems that Khan proposes, they are the interaction with modern economics, the role of revelation, assuming ideal Islamic society, and the general theory of Islamic economics.


2019 ◽  
Vol 18 (8) ◽  
pp. 581-597 ◽  
Author(s):  
Ambreen Fatima ◽  
Yasir Hasan Siddique

Flavonoids are naturally occurring plant polyphenols found universally in all fruits, vegetables and medicinal plants. They have emerged as a promising candidate in the formulation of treatment strategies for various neurodegenerative disorders. The use of flavonoid rich plant extracts and food in dietary supplementation have shown favourable outcomes. The present review describes the types, properties and metabolism of flavonoids. Neuroprotective role of various flavonoids and the possible mechanism of action in the brain against the neurodegeneration have been described in detail with special emphasis on the tangeritin.


2018 ◽  
Vol 6 (1) ◽  
pp. 45-56
Author(s):  
Lalrinzuali Sailo ◽  
◽  
Meesala Krishna Murthy ◽  
Khandayataray Pratima ◽  
Vikas Kumar Roy ◽  
...  

Monosodium glutamate is naturally available non-essential amino acids, which found in naturally occurring foods and used as flavour enhancer worldwide. Monosodium glutamate is believed to be linked with diverse health problems. The aim of the study was toxic effects of monosodium glutamate (MSG) and the protective role of L-carnitine, light on the available literature from last 25 years about diverse toxicity studies which had been carried out on animal and human models. Google scholar, NCBI, PUBMED, EMBASE, Wangfang databases, and Web of Science databases were used to retrieve the available studies. MSG was linked with deleterious effects particularly in animals including induction of obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects showed in Literature. Few reports revealed increased hunger, food intake, and obesity in human subjects due to MSG consumption. Hepatotoxic, neurotoxic, and genotoxic effects of monosodium glutamate on humans carried out very limitedly. High consumption of monosodium glutamate may be linked with harmful health effects showed in available literatures. So, it is recommended to use common salt instead of MSG. Furthermore, intensive research is required to explore monosodium glutamate–related molecular and metabolic mechanisms. L-carnitine can protect from Hepatotoxic, neurotoxic, renal impairment and genotoxic effects functionally, biochemically and histopathologically with a corresponding reduction of oxidative stress.


2021 ◽  
pp. 089331892199807
Author(s):  
Jonathan Clifton ◽  
Fernando Fachin ◽  
François Cooren

To date there has been little work that uses fine-grained interactional analyses of the in situ doing of leadership to make visible the role of non-human as well as human actants in this process. Using transcripts of naturally-occurring interaction as data, this study seeks to show how leadership is co-achieved by artefacts as an in-situ accomplishment. To do this we situate this study within recent work on distributed leadership and argue that it is not only distributed across human actors, but also across networks that include both human and non-human actors. Taking a discursive approach to leadership, we draw on Actor Network Theory and adopt a ventriloquial approach to sociomateriality as inspired by the Montreal School of organizational communication. Findings indicate that artefacts “do” leadership when a hybrid presence is made relevant to the interaction and when this presence provides authoritative grounds for influencing others to achieve the group’s goals.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 418
Author(s):  
Viola Zentrichová ◽  
Alena Pechová ◽  
Simona Kovaříková

The intent of this review is to summarize the knowledge about selenium and its function in a dog’s body. For this purpose, systematic literature search was conducted. For mammals, including dogs, a balanced diet and sufficient intake of selenium are important for correct function of metabolism. As for selenium poisoning, there are no naturally occurring cases known. Nowadays, we do not encounter clinical signs of its deficiency either, but it can be subclinical. For now, the most reliable method of assessing selenium status of a dog is measuring serum or plasma levels. Levels in full blood can be measured too, but there are no reference values. The use of glutathione peroxidase as an indirect assay is questionable in canines. Commercial dog food manufactures follow recommendations for minimal and maximal selenium levels and so dogs fed commercial diets should have balanced intake of selenium. For dogs fed home-made diets, complex data are missing. However, subclinical deficiency seems to affect, for example, male fertility or recovery from parasitical diseases. Very interesting is the role of selenium in prevention and treatment of cancer.


2020 ◽  
Vol 9 (2) ◽  
pp. 149-152
Author(s):  
Michael J. Balboni

AbstractThis article offers a brief response to constructive criticism of the book featured in this edition of Spiritual Care. Hostility to Hospitality argues that the role of spirituality within the care of sick patients, despite clear empirical evidence demonstrating its importance, remains deeply contested because of bias against religious communities. Deeply flawed conceptualizations of the nature of religion and the secular camouflage how a society's commitment to immanence functions like a spirituality. A secular framework weakens how spiritual communities can positively influence medical institutions or socialize professional guilds in caring for the whole patient. The diminishment of communities that champion compassion as a chief end, pave a way for hostile economic, technological, and bureaucratic forces to suppress our ability to fully care for patients in body and soul. Rather than being neutral as purported, the secular structures of medicine manipulate and use pastoral care for its own immanent ends. Hostility to Hospitality argues that unless pluralism is embraced, allowing for a diversity of religious communities to influence the structures of medicine, compassionate and holistic care will increasingly become unlikely as impersonal social forces increase.


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