BREES 2014_15

January Examination Feedback

Feedback on the January Examination The purpose of feedback is to promote and encourage reflection and improvement.

Summary Feedback takes many forms and is not limited to staff comments or marks. If you attempted the formative scientific writing exercise and then studied your attempt alongside the full mark scheme, you would at that time have been in receipt of feedback on your attempt. You would have been able to recognize where your attempt was both effective and where you might improve your approach. The January examination was sat by 291 students and the overall results are summarized graphically in figure 1.

Figure 1. Frequency histogram of the percentage marks provisionally awarded for the January examination. The examination had a single question – the construction of an abstract in no more than 250 words. The examination is worth 10% of the BREES Unit.

Staff observations Seven staff were involved in marking the abstracts. The following observations summarise the observations that were most commonly made. Titles The titles were not good overall. Most did not state the finding of the study and many drew the opposite conclusion to that supported by the results described in the abstract. Often the focus was on cold acclimation rather than the response to cold challenge. The title should seek to summarise the finding and not simply state the question being addressed. Page 1 of 10

BREES 2014_15

January Examination Feedback

Main Body Background & methods In general the background and methods were well covered. The points most often missed concerned the expression of genes related to UCP-1 in a wide variety of tissues. Many abstracts failed to include a statement of the experimental aim. More generally, the methods were more detailed than was necessary or warranted, and this left too little room for results and conclusions. Results The study was a comparison of wild-type and knockout animals but frequently the results for only one of these were included. Misunderstanding of O2 consumption results was common, or they were described so poorly that it was hard to understand the intended meaning. Conclusions Most abstracts stated the overall conclusion but didn't build up to this using the smaller conclusions that could be drawn from each element of the experiments included in the results. Structural aspects There was often ambiguity in expression that could lead to inaccuracy of statements and confusion. Many abstracts struck a poor balance between the sections and many lacked focus and used up the word count without saying anything relevant. Overall, however, the markers were very impressed by the quality of the abstracts, especially given the time constraint.

Practical steps to improvement The mark sheet used by staff to grade your title and abstract has been returned to you. Please find time to read your abstract and to consider the elements identified in the mark scheme. The examination paper is also available on Blackboard so you can repeat the abstracting exercise if you wish. Creating a summary of complex information is an important skill that many employers value highly and expect graduates to have. If the mark you were awarded is lower than you expected or would wish, we have some advice; practice, practice, practice.

Examination report Overall the examination ran smoothly. It was noted that the overwhelming majority of students turned up on time to the right session and were admirably quiet and well behaved when under examination conditions. Students in general arrived knowing what the examination would require in terms of electronic submission. There were some issues relating to word counts. These were communicated to staff only during the closing minutes of session 1. Briefly, there was a difference between the word count in Word and in the Blackboard test with the result that the count in Blackboard was higher than for the same text in Word. We have made extensive checks on this and have

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January Examination Feedback

discovered that some strings characters and spaces (e.g. 30 o C) appear to count as one word in Word but three words in Blackboard. We have scrutinized the abstract text submitted by all students and have used the ‘find/replace’ command to ensure that all the abstracts used the same (and minimum) number of words to describe temperature. So, for example, ‘X o C’, which includes spaces, was converted to ‘XoC’ which has no spaces. We checked all abstracts for this sort of wordcount difference and used find/replace to ensure that the same phrase was expressed by the same (and minimum) number of words in all abstracts. After this process was complete the number of abstracts that had a count of more than 250 words was reduced from 80 to 27. Finally, as the count in Word could be different and lower, all abstracts that had a word count over 250 words were copied into Word and the count in Word taken as the definitive word count for the abstract. This reduced the number of abstracts with a word count greater than 250 from 27 to 24.

Examples of good abstracts On the succeeding pages are several abstracts written by students in the January examination that were judged by staff to be ‘good examples’. All of them attracted more than 70% of the available marks (examination average = 62%). All abstracts have been reproduced by kind permission of the students who wrote them. In each case the abstract text and title are included along with an image showing the Turnitin report. Turnitin is a software system used throughout UK Universities to detect overlap between documents. Similarity between students’ work and a source text can indicate copying to a greater or lesser extent. Copying from a source is not appropriate academic practice and can lead directly to a charge of plagiarism. The Turnitin reports for the example abstracts all show a percentage similarity of zero (0%). One hundred and seventy students (of 291) had a ‘zero’ similarity score for their abstract.

Focus on improvement If you found the January examination difficult you are good company – almost all students will have been challenged by the examination task. There are practical steps you can take to improve. 1. 2. 3. 4.

Review the lecture on Scientific Writing (Mediasite tab). Revise the materials provided in the formative scientific writing folder (Research tab) Study the mark scheme for both the formative exercise and the examination Please understand. An abstract is not a list of facts, it is a structured explanation of a study; i) background necessary to understand the aim(s) and conclusions, ii) a statement of the aim of the study, iii) the essential aspects of the methods, iv) the key results which should allow the reader to understand the magnitude and direction of any changes and differences between groups (control and intervention) and v) a series of conclusions that relate back to the background and aim(s). An abstract should enable the reader to understand the study and its findings.

Please remember, summarising complex information is a significant challenge but it is a skill and all skills can be improved with purposeful practice. Drafted by Dr Phil Langton [13-02-2015]

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BREES 2014_15

January Examination Feedback

Example 1 UCP1-ablated mice demonstrate importance of non-shivering brown-adipose adaptive thermogenesis in acclimation to cold. The original uncoupling protein UCP1 (thermogenin) and the heat it generates in brown adipose tissue via non-shivering mechanisms is today accepted as a major contributor to thermoregulation, but the existence of sequence-related but more widely distributed proteins such as UCP2 and UCP3 raises the possibility of other, alternative, non-shivering thermogenesis which may confer tolerance to cold. Groups of wild-type and UCP1-ablated mice were acclimated to ambient temperatures of 30, 24 and 18°C for at least 3 weeks and then transferred to 4°C (cold), with their body temperatures monitored rectally and rate of thermogenesis estimated via oxygen consumption. The wild-type mice acclimated to 24 and 18°C maintained their body temperature while only the UCP1-ablated mice acclimated at 18°C could do the same. The 30°C-acclimated UCP1-ablated mice demonstrated a lower increase in oxygen consumption than their wild-type counterparts, indicating lower metabolic rate, however the oxygen consumption was identical between the two groups acclimated to 18°C. Separately, shivering intensity at 4°C of mice acclimated to 30 (WA) and 4°C (CA) was measured via electromyogram (EMG). WA wild-type mice at 4°C showed approximately three times the shivering intensity than at 30°C, but there was almost no increase amongst CA mice. UCP1-ablated mice were no different to wild-type mice at 30°C, but at 4°C the shivering was far higher amongst CA mice, almost matching that of the WA mice. The impaired cold-tolerance of the UCP1-ablated mice and their apparent increased shivering when cold-acclimated indicates that non-shivering, non-brown adipose tissue thermogenesis does not contribute to thermoregulation. Count 250

Turnitin report. Result – 0% similarity with examination paper

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January Examination Feedback

Example 2 Using thermogenin ablated mice, temperature loss, oxygen consumption and electromyography to identify alternate mechanisms of nonshivering thermogenesis. The action of thermogenin (UCP1) in brown adipose tissue has long been recognised as a key contributor to nonshivering thermogenesis. However, the identification of related but widely distributed genes, such as UCP2, has raised questions about whether additional mechanisms exist. UCP1 ablated mice enable examination of compensatory mechanisms for adapting to the cold. Female C57BI/6 mice were used for both wild type (wt) and ablated mice, which were divided into age matched groups. The UCP1 gene was knocked out using homologous recombination and groups were acclimated to 30, 24 and 18°C prior to the experiment. The mice were exposed to 4°C and had their body temperatures taken before and after. Our results show that for the 30 and 24°C groups, temperature was lost from the ablated mice more, but the 18°C groups were similar. Additionally, the oxygen consumption was taken (as a measurement of thermogenesis). The ablated 30°C mice had lower oxygen consumption then the wt mice, but the 18°C mice were similar. To determine if an alternative nonshivering method had been used in the ablated mice we used an electromyogram (EMG) to measure shivering at 4°C and thermoneutrality. The wt mice’s shivering, acclimated to 4°C, did not change much from 30 to 4°C whereas the 30°C group’s changed threefold. The ablated mice shivered as much at both temperatures, suggesting that ablated mice were most probably using shivering to compensate for heat loss and the wt using UCP1 and shivering; an alternate nonshivering method was not identified. Count 247

Turnitin report. Result – 0% similarity with examination paper

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January Examination Feedback

Example 3 The capability of UCP-1 ablated mice to produce heat and maintain body temperature via non-shivering thermogenesis The process of adaptive non-shivering thermogenesis has only been recognised in recent years. It has already been noted that uncoupling protein UCP-1, found in brown adipose tissue, contributes significantly to this process. Alterntative mechanisms for non-shivering thermogenesis are sought after, and proteins that are related to UCP-1 in sequence (e.g. UCP-2, UCP3) have been identified. Research into these proteins is important as they are distributed more widely across different tissues. The ability of UCP-1 ablated mice to produce heat from alternative sources to the brown adipose tissue was studied. Wild type mice (of the C57B1/6 strain) and UCP-1 ablated mice were used. Their body temperature was acclimated to 30, 24 or 18 degrees, and the mice were subsequently exposed to a temperature of 4 degrees. Oxygen consumption in response to cold stimuli was measured to assess thermogenesis. It was observed that UCP-1 ablated mice can develop cold tolerance; specifically those mice who had initially been aclimated to 18 degrees, who were able to maintain their normal body temperature at 4 degrees. The same mice were able to sustain a similar rate of oxygen consumption as their wild type counterpart at 4 degrees. In addition, EMG (electrodes for electromyogram) recording were inserted into mice acclimated to 30 or 4 degrees to determine basal muscle activity and thus changes to muscle activity at colder temperatures. Cold-acclimated wild type mice did not shiver at 4 degrees, whereas the cold-acclimated UCP-1 ablated mice continued to shiver at 4 degrees and muscle activity remained high. Count 250

Turnitin report. Result – 0% similarity with examination paper

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January Examination Feedback

Example 4 UCP1-ablated mice rely on shivering to sustain body temperature and do not have alternative nonshivering thermogenesis mechanisms. Action of UCP1 (thermogenin) on brown adipose tissue is the main mechanism of heat generation in adaptive nonshivering thermogenesis. The discovery of proteins (UCP2, UCP3) related in sequence to UCP1 in other tissues suggests that other mechanisms also exist, and these would impact on bioenergetics, metabolic, obesity, and thermoregulatory research. We used UCP1-ablated mice, which rely completely on producing heat from sources other than brown adipose tissue, to measure their ability to develop compensatory mechanisms for survival in cold, with an aim to uncover brown adipose tissue independent types of nonshivering thermogenesis. WT (C57BI/6 strain) and UCP1-ablated (C57BI/6-derived, with UCP1 inactivated by homologous recombination) adult mice were age-matched and acclimated to 30, 24 and 18 degrees C for three weeks. Body temperature and oxygen consumption were measured (by rectal probe and respiratory chamber) in response to a transfer to 4 degrees. WT 30-acclimated and UCP1-ablated 30 and 24-acclimated mice did not develop cold tolerance, but UCP-ablated cold-acclimated mice could sustain normal temperature as well as the corresponding WT. Shivering was recorded using EMG signals, the mean rectified value was measured. Warm-acclimated WT mice shivered intensely at 4 degrees, whereas cold-acclimated WT mice did not. Oxygen consumption in both conditions was higher in the cold. Both warm and cold-acclimated UPC1-ablated mice shivered at 4 degrees, despite no change in basal muscle activity compared to WT. Therefore UCP1ablated mice relied on shivering to do sustain their body temperature. They did not develop an alternative nonshivering thermogenesis mechanism in the absence of UCP1. Count 247

Turnitin report. Result – 0% similarity with examination paper

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January Examination Feedback

Example 5 Testing of acclimation-induced cold tolerance in wild-type and UCP1-ablated recombinant mice determining primary mechanisms of thermogenesis. There are two types of thermogenesis, shivering and nonshivering. Brown adipose tissue (BAT) is responsible for nonshivering thermogenesis via uncoupling protein UCP1. It is possible that UCP2/3 could also be responsible for nonshivering thermogenesis. UCP1 gene inactivation produces UCP1-ablated mice, whom are unable to produce heat in BAT, therefore depend on other methods of heat production. The aim is to discover compensatory mechanisms for cold conditions in mice lacking UCP1 protein. Wild-type and UCP1-ablated mice were acclimated to either 30, 24 or 18 degrees for 3 weeks, then transferred to a 4°C environment. Body temperature was monitored and the value for thermogenesis was estimated by oxygen consumption. Determining the dominant thermogenesis mechanism for both mice groups, EMG recordings (presented as Umrv) were conducted in cold and thermoneutral conditions, to demonstrate shivering intensity. 30°C acclimated wild-type and UCP1-ablated were unable to compensate with thermoregulatory mechanisms when acutely placed into 4°C, yet UCP1-ablated body temperature decrease was faster. 18°C acclimated UCP1-ablated mice maintained temperature as well as wildtype. Oxygen consumption of UCP1-ablated mice always appeared lower than corresponding wild-types. There was no significant difference between groups. The UCP1ablated mice did not show large differences in muscle activity (Umrv) between the two acclimated groups when exposed to cold and thermoneutral temperatures, in comparison to wild-type exposure to 4°C which was threefold greater than at 30°C. The higher the temperature of acclimation, the greater the decrease in body temperature when exposed to cold. It appears that BAT are the main thermoregulatory mechanism in mice. Count 250 Turnitin report. Result – 0% similarity with examination paper

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January Examination Feedback

Example 6 Testing potential non-brown-fat-derived non-shivering thermogenesis adaptations on UCP1-ablated mice, compared to wild-type donor mice, when acclimated at different temperatures. Adaptive non-shivering thermogenesis is essential for thermoregulation. Todays accepted mechanism of action is in uncoupling protein UCP1, a thermogenin found in brown adipose tissue. However, the recent discovery of related proteins, found in different tissues (UCP2, UCP3 etc.) may also play a role in non-shivering thermoregulation. Although this has not yet been explored. Non-brown-fat-derived non-shivering thermogenesis could be crucial for bioenergetics, metabolic and obesity research. Using homologous recombination to inactivate the UCP1 gene from a donor strain, C57B1/6, and checking UCP1 detection with polyclonal antibodies, we tested age-matched groups of female UCP1-ablated mice to the original donor wild-type. Acclimation occurred for 3 weeks at temperatures of 30, 24 and 18°C, then immediate transferral to 4°C. Body temperature was recorded via a rectal probe. Oxygen consumption and EMG recordings were used to measure metabolic rate and muscle activity increases due to shivering. Body temperature of both UCP1-ablated and wild-type mice fell rapidly when acclimated at 30°. Both constant at 18°C and only UCP1-ablated mice fell at 24°C. Both had similar oxygen consumptions at 18°C and UCP1-ablated mice had a lower oxygen consumption at 30°C. Equally high EEG readings when acclimated at 30°C and wild-type showed a significant decrease in muscle activity when acclimated at 4°C but UCP1ablated mice had a higher increase. This shows that UCP1 has a significant effect on thermoregulation and without it shivering thermogenesis is the main method used. Other uncoupled proteins may have no effect on thermoregulation and may have a different role throughout the body. Count 249 Turnitin report. Result – 0% similarity with examination paper

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January Examination Feedback

Example 7 Uncoupling protein UCP1 is found to be vital to adaptive nonshivering thermogenesis after UPC1-abalation causes poor thermogenesis in mice. Uncoupling protein 1, found in brown adipose tissue, is a major contributor to adaptive nonshivering thermogenesis. This study investigates the possibility of an alternative mechanism, perhaps involving non-brown adipose UPCs. The discovery of such a mechanism would have impacts in bioenergetics, metabolic and obesity research. In preparation, UCP1 gene was ablated through homologous recombination to give UCP1 (-/-) mice. Acclimatisation of the mice was carried out for 3 weeks at 18°C, 24°C and 30°C. Acute cold exposure was at 4°C and body temperature was measured every 30 minutes. Oxygen consumption was measured to give an estimate of thermogenesis. An EMG was used to collect muscle activity data of the 4°C and 30°C acclimated mice in an environment of 4°C and 30°C. The mean rectified value was then used to quantify the raw trace. During acute cold exposure, the 24°C and 30°C acclimated UCP1-ablated mice saw a poor maintenance of body temperature compared to wild-type (donor strain) mice. UCP1-ablated mice had a lower oxygen consumption increase than wild-type mice, indicating thermogenesis was decreased. Muscle activity in 4°C acclimated mice was 3-fold higher in UCP1-ablated mice at 4°C than it was for wild-type mice due to shivering and locomotion. In conclusion, UCP1ablated mice were poorer at maintaining body temperature and had decreased thermogenesis during acute cold exposure than wild-type mice. UCP1-ablated mice relied upon shivering at 4°C, despite previous acclimation to the cold, whereas the wild-type did not. This suggests that UCP1 is vital to a good adaptive nonshivering thermogenesis response. Count 249 Turnitin report. Result – 0% similarity with examination paper

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