User talk:Jiajie Ma/sandbox

Assignment 3

Original- "Extremophile"

Astrobiology is the field concerned with forming theories, such as panspermia, about the distribution, nature, and future of life in the universe. In it, microbial ecologists, astronomers, planetary scientists, geochemists, philosophers, and explorers cooperate constructively to guide the search for life on other planets. Astrobiologists are particularly interested in studying extremophiles, as many organisms of this type are capable of surviving in environments similar to those known to exist on other planets. For example, Mars may have regions in its deep subsurface permafrost that could harbor endolith communities. The subsurface water ocean of Jupiter's moon Europa may harbor life, especially at hypothesized hydrothermal vents at the ocean floor.

Recent research carried out on extremophiles in Japan involved a variety of bacteria including Escherichia coli and Paracoccus denitrificans being subject to conditions of extreme gravity. The bacteria were cultivated while being rotated in an ultracentrifuge at high speeds corresponding to 403,627 g (i.e. 403,627 times the gravity experienced on Earth). Paracoccus denitrificans was one of the bacteria which displayed not only survival but also robust cellular growth under these conditions of hyperacceleration which are usually found only in cosmic environments, such as on very massive stars or in the shock waves of supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of panspermia.

On 26 April 2012, scientists reported that lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity within the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).

On 29 April 2013, scientists at Rensselaer Polytechnic Institute, funded by NASA, reported that, during spaceflight on the International Space Station, microbes seem to adapt to the space environment in ways "not observed on Earth" and in ways that "can lead to increases in growth and virulence".

On 19 May 2014, scientists announced that numerous microbes, like Tersicoccus phoenicis, may be resistant to methods usually used in spacecraft assembly clean rooms. It's not currently known if such resistant microbes could have withstood space travel and are present on the Curiosity rover now on the planet Mars.

On 20 August 2014, scientists confirmed the existence of microorganisms living half a mile below the ice of Antarctica.

References

Edit- "Extremophile"

Astrobiology is the field concerned with forming theories, such as panspermia, about the distribution, nature, and future of life in the universe. In it, microbial ecologists, astronomers, planetary scientists, geochemists, philosophers, and explorers cooperate constructively to guide the search for life on other planets. Astrobiologists are particularly interested in studying extremophiles, as many organisms of this type are capable of surviving in environments similar to those known to exist on other planets. For example, analogous deserts of Antarctica are exposed to harmful UV radiation, low temperature, high salt concentration and low mineral concentration. These conditions are similar to those on Mars. Therefore, finding viable microbes in the subsurface of Antarctica suggests that there maybe microbes such as endolithic communities live under Martian surface.

Recent research carried out on extremophiles in Japan involved a variety of bacteria including Escherichia coli and Paracoccus denitrificans being subject to conditions of extreme gravity. The bacteria were cultivated while being rotated in an ultracentrifuge at high speeds corresponding to 403,627 g (i.e. 403,627 times the gravity experienced on Earth). Paracoccus denitrificans was one of the bacteria which displayed not only survival but also robust cellular growth under these conditions of hyperacceleration which are usually found only in cosmic environments, such as on very massive stars or in the shock waves of supernovas. Analysis showed that the small size of prokaryotic cells is essential for successful growth under hypergravity. The research has implications on the feasibility of panspermia.

On 26 April 2012, scientists reported that lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity within the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).

On 29 April 2013, scientists at Rensselaer Polytechnic Institute, funded by NASA, reported that, during spaceflight on the International Space Station, microbes seem to adapt to the space environment in ways "not observed on Earth" and in ways that "can lead to increases in growth and virulence".

On 19 May 2014, scientists announced that numerous microbes, like Tersicoccus phoenicis, may be resistant to methods usually used in spacecraft assembly clean rooms. It's not currently known if such resistant microbes could have withstood space travel and are present on the Curiosity rover now on the planet Mars.

On 20 August 2014, scientists confirmed the existence of microorganisms living half a mile below the ice of Antarctica.

On Jan. 09. 2015, scientists from CNR-National Research Council of Italy reported that S.soflataricus was able to survive under Martian radiation at a wavelength that was considered extremely lethal to most bacteria. This discovery overturned the dogma that only some bacteria spores were extremely resistant to UV radiation. It also encouraged future researches on S.soflatarcus in space missions to understand what mechanisms this organism uses to survive under extreme conditions.

On June 2016, scientists from Brigham Young University reported that endospores of Bacillus Subtilis were able to survive high velocity impacts, extreme shock, and extreme deceleration. They pointed out that this characteristic might allow endospores to survive and be transferred to other locations while experiencing atmosphere disruption or meteorite impact events. Furthermore, they also suggested that a spacecraft might carry spores on its surface, and while it had a hard landing, those spores would impact the landing surface directly and stick on it . Due to their high survivability rate, those spores are likely to survive in a foreign planet.

Notes

Jiajie Ma (talk) 03:34, 8 October 2017 (UTC)

Assignment 2

Wikipedia Article:Extremophile

Since 1980s, when scientists first discovered microbial lives had abilities to survive in extreme environments, studies have been focusing on these microorganisms because the environments that they live resemble the environment of the early earth and other planets. Therefore, studying extremophiles may provide scientists with an insight into the origin of lives on the earth and the potential of Martian lives . Furthermore, the studies may also aid in future search- for- life missions to other planets.

The “In astrobiology” section introduces the relationship between astrobiology and extremophiles, and it has many recently published findings. However, some of the references are not reliable. For example, the second to last sentence of the first paragraph states that endolithic communities can survive on Mars. However, the reference is from newspapers, which only describes the extreme environment in an African mine and how surprised the scientists were when they discovered microorganisms there. The reference does not relate the environment of the mine to that of Mars and not even suggest that endolithic communities could be live on Mars. Therefore, this reference should be replaced. Furthermore, the second and third paragraphs are both supported by two references. In both cases, one of the references are from either news or blogs, whereas the other references are from independent research papers which are sufficient to support the contents of this article.

To make the second to last sentence of the first paragraph more convincing and detailed, I will paraphrase Wynn-Williams’s work. He focuses on extremophiles on Antarctic desserts which are analogous to Martian habitats, and he proposes that endolithic communities may live on Mars.

I will add two recently published findings because they contribute to theories and applications that help astrobiologists to search for lives on other planets. One of them is about some extremophiles that can survive to stimulated space conditions. This guides astrobiologists to look for specific environments to search for lives. The other shows Bacillus subtilis spores are capable of surviving under high speed condition, which indicates that microbial transfer in space is possible.

Note

Jiajie Ma (talk) 04:12, 28 September 2017 (UTC)

Assignment 1

Wikipedia article: Anaerobic Respiration

This article lacks consistency of applying terms. In its introduction, it uses “electron acceptor”, “final electron acceptor”, and “terminal electron acceptor” to describe the final molecule that accepts electrons in ETC. As we have learned in MICB 301, the “terminal electron acceptor” is the proper term to use. Using consistent language helps readers understand the contents easier.

Some sentences are redundant. In the section of Ecological Importance, the first two sentences have the same content that anaerobic respiration impacts the carbon cycle. These sentences should be combined to make the article more succinct.

This article has references which come from independent and authentic microbiology journals and are recently published. Most of the references are closely related to and support the article’s content. However, the fifth reference is contradictory to the statement in the end of Ecological Importance section. The reference mainly talked about the ecological benefits of sulfate respiration – it leads to a suppression of methanogenesis and an increasing of plant growth. It does not mention that anaerobic respiration will cause heavy metal precipitation, which is written in the article. This information should be deleted, or more relevant references should be provided.

Most sections composed on this Wikipedia page are relevant to anaerobic respiration. Nevertheless, as people discussed on talk page, fermentation is overrepresented on this page. Fermentation is a different biological pathway compared to anaerobic respiration. It should not be shown on this page, or a hyperlink should be provided for readers who may also be interested in fermentation.

Jiajie Ma (talk) 02:12, 18 September 2017 (UTC)

Jiajie Ma's Peer Review

Reviewing your edits, the structure of your content is easily comprehensible, and the additional sections are appropriately placed following the chronological ordering of the original article. In addition, the written information is conveyed in a clear, yet concise manner. However, I would suggest being wary of consistency when listing the dates of discoveries within your edits. As it stands, some of your dates are formatted slightly differently from the previous ones, and the published date of your S. soflataricus section is listed differently within your references. Furthermore, there is some close-paraphrasing when you’re discussing implications of endospores of Bacillus subtilis in your final paragraph. As such, I suggest that you rephrase the statement to avoid plagiarism, and provide one that is more applicable and general for your article on extremophiles, which is a broad class of organisms.

As for your content, your edits support most of the key aspects of extremophiles within astrobiology, as your evidence is relevant and supportive of the argument within the rest of the article. Therefore, your sources are well-chosen, and you demonstrate the ability to clearly extrapolate some of the key points from the published literature. However, your last two sentences from your S. soflataricus paragraph and the last sentence in your Bacillus subtilis paragraph are quite strongly opinionated, as well as not appearing to be supported by your references, and thus should be removed or restated. As a suggestion, you should review the author’s results and conclusions and try to construct a more general statement, one that avoids a suggestive tone to remove bias, while also promoting a neutral opinion. Additionally, providing explanations such as describing the significance of these findings in relation to extremophiles, can contribute to developing a greater depth of understanding about the importance of extremophiles in astrobiology. --Deelye (talk) 19:11, 9 November 2017 (UTC)