title: Sleep duration and physical performance during a 6-week military training course

authors: Edgar, David T.

subjects: Science & Technology

abstract: Sleep is vital in influencing effective training adaptations in the military. This study aimed to assess the relationship between sleep and changes in physical performance over 6-weeks of military training. A total of 22 officer-trainees (age: 24 ± 5 y) from the New Zealand Defence Force were used for this observational longitudinal cohort study. Participants wore wrist actigraphs to monitor sleep, completed subjective wellbeing questionnaires weekly, and were tested for: 2.4 km run time-trial, maximum press-up and curl-ups before and after 6-weeks of training. Average sleep duration was calculated over 36-nights (6:10 ± 0:28 h:min), and sleep duration at the mid-point (6:15 h:min) was used to stratify the trainees into two quantile groups (UNDERS: 5:51 ± 0:29 h:min, n =11) and (OVERS: 6:27 ± 0:09 h:min, n =11). There were no significant group x time interactions for 2.4 km run, press-ups, or curl-ups (p >0.05); however, small effects were observed in favour of OVERS for 2.4 km run (59.8 vs 44.9 s; d =0.26) and press-ups (4.7 vs 3.2 reps; d = 0.45). Subjective wellbeing scores resulted in a significant group x time interaction (p <0.05), with large effect sizes in favour of the OVERS group for Fatigue in Week 1 (d =0.90) and Week 3 (d =0.87), and Soreness in Week 3 (d =1.09) and Week 4 (d =0.95). Sleeping more than 6:15 h:min per night over 6-weeks was associated with small benefits to aspects of physical performance and moderate to large benefits on subjective wellbeing measures when compared to sleeping less than 6:15 h:min.

text: Sleep duration and physical performance during a 6-week military training course Sleep is vital in influencing effective training adaptations in the military. This study aimed to assess the relationship between sleep and changes in physical performance over 6-weeks of military training. A total of 22 officer-trainees (age: 24 ± 5 y) from the New Zealand Defence Force were used for this observational longitudinal cohort study. Participants wore wrist actigraphs to monitor sleep, completed subjective wellbeing questionnaires weekly, and were tested for: 2.4 km run time-trial, maximum press-up and curl-ups before and after 6-weeks of training. Average sleep duration was calculated over 36-nights (6:10 ± 0:28 h:min), and sleep duration at the mid-point (6:15 h:min) was used to stratify the trainees into two quantile groups (UNDERS: 5:51 ± 0:29 h:min, n =11) and (OVERS: 6:27 ± 0:09 h:min, n =11). There were no significant group x time interactions for 2.4 km run, press-ups, or curl-ups (p >0.05); however, small effects were observed in favour of OVERS for 2.4 km run (59.8 vs 44.9 s; d =0.26) and press-ups (4.7 vs 3.2 reps; d = 0.45). Subjective wellbeing scores resulted in a significant group x time interaction (p <0.05), with large effect sizes in favour of the OVERS group for Fatigue in Week 1 (d =0.90) and Week 3 (d =0.87), and Soreness in Week 3 (d =1.09) and Week 4 (d =0.95). Sleeping more than 6:15 h:min per night over 6-weeks was associated with small benefits to aspects of physical performance and moderate to large benefits on subjective wellbeing measures when compared to sleeping less than 6:15 h:min.

year: 2021-05-25

title: Unified Total Site Heat Integration: Targeting, Optimisation and Network Design

authors: Tarighaleslami, Amir Hossein

subjects: Total Site Heat Integration

abstract: Process industries in New Zealand use 214.3 PJ of process heat, of which approximately 65 % is fossil fuels. Despite increasing energy demands, depleting fossil fuel resources, and pressure to reduce Greenhouse Gas emissions, low grade heat in large-scale processing sites is still not fully utilised. This thesis presents methods to target, optimise and design more practical heat recovery systems for large industrial sites, i.e. Total Sites, and overcome technical limitations of current methods. Original contributions of this thesis to literature include novel developments and applications in six areas: i) a new Total Site Heat Integration (TSHI) targeting method – Unified Total Site Targeting (UTST) –  which sets realistic targets for isothermal and non-isothermal utilities and heat recovery via the utility system; ii) a new TSHI optimisation and utility temperature selection method to optimise Total Cost of the utility system; iii) a new Utility Exchanger Network synthesis and design method based on the targets achieved by the UTST method and optimal temperatures from optimisation method; iv) a new method for calculating assisted heat transfer and shaft work to further improve TSHI cogeneration and performance; v) examination of heat transfer enhancement techniques in TSHI to achieve higher heat recovery and lower required area by substituting conventional utility mediums by nanofluids in the utility system; and vi) a spreadsheet software tool called Unified Total Site Integration to apply the developed methods to real industrial cases. 
The developed methods have been applied to three large industrial case studies. Results confirm that heat recovery and utility targets obtained from the UTST method were lower but more realistic to achieve in practice when compared to conventional TSHI methods. The three industrial case studies represent a wide variety of processing industries. In summary, the over-estimation of TSHI targets for the three case studies from using the conventional method compared to the new method are 0.2 % for the Södra Cell Värö Kraft Pulp Mill, 22 % for a New Zealand Dairy Factory, and 0.1 % for Petrochemical Complex. The Total Annualised Costs (TAC) for the three case studies are minimised using a new derivative based approach. Results show TAC reductions 4.6 % for Kraft Pulp Mill, 0.6 % for Dairy Factory, and 3.4 % for Petrochemical Complex case studies. In addition, sensitivity analysis for the optimisation is undertaken. The UTST method with its modified targeting procedure is demonstrated to generate simpler Utility Exchanger Network designs compared to conventional methods, which confirm the original targets are realistic and achievable. A new method for calculating assisted heat integration targets applied to an example Total Site problem increased heat recovery by 1,737 kW, which is a 21% increase in Total Site heat recovery, and increased shaft work by 80 kW. Lastly, the addition of nanoparticles to create a closed nanofluid heat recovery systems shows heat recovery from liquid-liquid heat exchangers increases of 5 % to 9 % using an intermediate fluid with 1.5 vol. % CuO/water.

text: Unified Total Site Heat Integration: Targeting, Optimisation and Network Design Process industries in New Zealand use 214.3 PJ of process heat, of which approximately 65 % is fossil fuels. Despite increasing energy demands, depleting fossil fuel resources, and pressure to reduce Greenhouse Gas emissions, low grade heat in large-scale processing sites is still not fully utilised. This thesis presents methods to target, optimise and design more practical heat recovery systems for large industrial sites, i.e. Total Sites, and overcome technical limitations of current methods. Original contributions of this thesis to literature include novel developments and applications in six areas: i) a new Total Site Heat Integration (TSHI) targeting method – Unified Total Site Targeting (UTST) –  which sets realistic targets for isothermal and non-isothermal utilities and heat recovery via the utility system; ii) a new TSHI optimisation and utility temperature selection method to optimise Total Cost of the utility system; iii) a new Utility Exchanger Network synthesis and design method based on the targets achieved by the UTST method and optimal temperatures from optimisation method; iv) a new method for calculating assisted heat transfer and shaft work to further improve TSHI cogeneration and performance; v) examination of heat transfer enhancement techniques in TSHI to achieve higher heat recovery and lower required area by substituting conventional utility mediums by nanofluids in the utility system; and vi) a spreadsheet software tool called Unified Total Site Integration to apply the developed methods to real industrial cases. 
The developed methods have been applied to three large industrial case studies. Results confirm that heat recovery and utility targets obtained from the UTST method were lower but more realistic to achieve in practice when compared to conventional TSHI methods. The three industrial case studies represent a wide variety of processing industries. In summary, the over-estimation of TSHI targets for the three case studies from using the conventional method compared to the new method are 0.2 % for the Södra Cell Värö Kraft Pulp Mill, 22 % for a New Zealand Dairy Factory, and 0.1 % for Petrochemical Complex. The Total Annualised Costs (TAC) for the three case studies are minimised using a new derivative based approach. Results show TAC reductions 4.6 % for Kraft Pulp Mill, 0.6 % for Dairy Factory, and 3.4 % for Petrochemical Complex case studies. In addition, sensitivity analysis for the optimisation is undertaken. The UTST method with its modified targeting procedure is demonstrated to generate simpler Utility Exchanger Network designs compared to conventional methods, which confirm the original targets are realistic and achievable. A new method for calculating assisted heat integration targets applied to an example Total Site problem increased heat recovery by 1,737 kW, which is a 21% increase in Total Site heat recovery, and increased shaft work by 80 kW. Lastly, the addition of nanoparticles to create a closed nanofluid heat recovery systems shows heat recovery from liquid-liquid heat exchangers increases of 5 % to 9 % using an intermediate fluid with 1.5 vol. % CuO/water.

year: 2018

title: Māori medical student and physician exposure to racism, discrimination, harassment, and bullying

authors: Cormack, Donna

abstract: IMPORTANCE: Discrimination, bullying, and harassment in medicine have been reported internationally, but exposures for Indigenous medical students and physicians, and for racism
specifically, remain less examined.
OBJECTIVE: To examine the prevalence of racism, discrimination, bullying, and harassment for Māori medical students and physicians in New Zealand and associations with demographic and clinical
characteristics.
DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study used data from an anonymous national survey of Māori medical students and physicians in New Zealand in late 2021 and early 2022.
Data were analyzed from March 2022 to April 2024.
EXPOSURES: Age, gender, marginalized status (ie, in addition to being Māori, belonging to other groups traditionally marginalized or underrepresented in medicine), year of medical school, year of
graduation, and main work role.
MAIN OUTCOMES AND MEASURES: Direct and witnessed racism, discrimination, bullying, and harassment were measured as any experience in the last year and ever. Any exposure to negative
comments about social groups and witnessing discriminatory treatment toward Māori patients or whānau (extended family). Considering leaving medicine, including because of mistreatment, was
measured.
RESULTS: Overall, 205 Māori medical students (median [IQR] age, 23.1 [21.6-24.3] years; 137 [67.2%] women) and 200 physicians (median [IQR] age, 36.6 [30.1-45.3] years; 123 [62.8%] women)
responded. Direct and witnessed exposure to racism (184 students [91.5%]; 176 physicians [90.7%]) and discrimination (176 students [85.9%]; 179 physicians [89.5%]) ever in medical education,
training, or work environments was common. Ever exposure to witnessed and direct bullying (123 students [66.5%]; 150 physicians [89.3%]) and harassment (73 students [39.5%]; 112 physicians
[66.7%]) was also common. Most respondents reported witnessing Māori patients or their whānau being treated badly in clinical settings, in direct interactions (67 students [57.8%]; 112 physicians
[58.9%]) or behind their backs (87 students [75.0%]; 138 physicians [72.6%]). One-quarter of Māori medical students (45 students), and 37.0%of physicians (61 physicians) had considered leaving or taken a break from medicine because of these experiences. Additional marginalized statuses were significantly associated with any direct experience of mistreatment in the last year for students and physicians. Exposure to some forms of mistreatment were also significantly associated with higher likelihood of thinking about leaving or taking a break from medicine for physicians.
CONCLUSIONS AND RELEVANCE: In this study, Māori medical students and physicians reported high exposure to multiple forms of racism, discrimination, bullying, and harassment in medical
education, training, and work environments, requiring an urgent response from medical institutions.

text: Māori medical student and physician exposure to racism, discrimination, harassment, and bullying IMPORTANCE: Discrimination, bullying, and harassment in medicine have been reported internationally, but exposures for Indigenous medical students and physicians, and for racism
specifically, remain less examined.
OBJECTIVE: To examine the prevalence of racism, discrimination, bullying, and harassment for Māori medical students and physicians in New Zealand and associations with demographic and clinical
characteristics.
DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study used data from an anonymous national survey of Māori medical students and physicians in New Zealand in late 2021 and early 2022.
Data were analyzed from March 2022 to April 2024.
EXPOSURES: Age, gender, marginalized status (ie, in addition to being Māori, belonging to other groups traditionally marginalized or underrepresented in medicine), year of medical school, year of
graduation, and main work role.
MAIN OUTCOMES AND MEASURES: Direct and witnessed racism, discrimination, bullying, and harassment were measured as any experience in the last year and ever. Any exposure to negative
comments about social groups and witnessing discriminatory treatment toward Māori patients or whānau (extended family). Considering leaving medicine, including because of mistreatment, was
measured.
RESULTS: Overall, 205 Māori medical students (median [IQR] age, 23.1 [21.6-24.3] years; 137 [67.2%] women) and 200 physicians (median [IQR] age, 36.6 [30.1-45.3] years; 123 [62.8%] women)
responded. Direct and witnessed exposure to racism (184 students [91.5%]; 176 physicians [90.7%]) and discrimination (176 students [85.9%]; 179 physicians [89.5%]) ever in medical education,
training, or work environments was common. Ever exposure to witnessed and direct bullying (123 students [66.5%]; 150 physicians [89.3%]) and harassment (73 students [39.5%]; 112 physicians
[66.7%]) was also common. Most respondents reported witnessing Māori patients or their whānau being treated badly in clinical settings, in direct interactions (67 students [57.8%]; 112 physicians
[58.9%]) or behind their backs (87 students [75.0%]; 138 physicians [72.6%]). One-quarter of Māori medical students (45 students), and 37.0%of physicians (61 physicians) had considered leaving or taken a break from medicine because of these experiences. Additional marginalized statuses were significantly associated with any direct experience of mistreatment in the last year for students and physicians. Exposure to some forms of mistreatment were also significantly associated with higher likelihood of thinking about leaving or taking a break from medicine for physicians.
CONCLUSIONS AND RELEVANCE: In this study, Māori medical students and physicians reported high exposure to multiple forms of racism, discrimination, bullying, and harassment in medical
education, training, and work environments, requiring an urgent response from medical institutions.

year: 0202-07-01