Modified Blowfish algorithm analysis using derivation cases

This study analyzed and enhanced the modified Blowfish algorithm (MBA) encryption. The modification retained the original structure, process and the use of two S-boxes in the MBA but presented two derivation processes in the f-function which was originally placed to prevent symmetry. The derivation case’s performance was analyzed using avalanche effect and time efficiency. After comparing the first and second derivation process presented in the MBA, the second derivation further improved the avalanche effect by 5.47%, thus improving security. The performance also showed that the second modification is faster by 39.48% in encryption time, and 38.34% faster in decryption time. The first derivation case in the modified Blowfish was slower in time because of the difference in the placement of the shift rotation. The key generation time was found to be independent of the input size while the encryption and decryption time was found to be directly proportional to file size. With this, the second modification is considered to be better.

Fatigue Through Sleep Time On Night Service Nurses At Kendari City Hospital

Sleep time is the sleep time needed by nurses as a fulfillment before doing the night shift and sleeping time during the night shift to optimize work productivity to minimize work fatigue. This study aims to determine the relationship between nurses' slept time before and during shifts, slept debt, and shift rotation with fatigue on night shift nurses in the Critical Room of the Kendari City General Hospital in 2020. An analytical survey was conducted with a cross-sectional study. The results showed that there was no relationship between sleep time before the night shift and work fatigue on the night watch nurse (p-value = 0.309), in contrast to sleep time during the night shift, it was found that there was a relationship with work fatigue on the night watch nurse (p-value = 0.003 ). It is recommended that hospital management make standard operating procedures that aim to regulate nurses' sleep time during the night shift to meet their needs and reduce fatigue levels.

306 Circadian activity rhythms and alertness among rapid-shift work female nurses

Introduction Circadian rhythms play an important role in regulating sleep. Sleep disturbances are prevalent in shift-work nurses, particularly for those work in rapid-shift rotation, including night shifts and day shifts. This study aimed to: 1) describe the characters of sleep-wake index (total sleep time [TST], wake after sleep onset [WASO], circadian activity rhythms [CAR]), psychomotor vigilance test (PVT), salivary cortisol, fatigue, and activity level during 8- and 12-hour rapid-shift work nurses; and 2) compare the parameters between two different shifts. Methods This exploratory study used registered nurses (RNs) from nine intensive care units in Beijing area. 7-days consecutive wrist actigraphy data, including TST and WASO were collected. Cosiner analysis was used for computing the CAR, including amplitude and mesor. PVT and saliva cortisol were used to assess alertness level, which measured before and after shift. Self-reported fatigue severity was measured by Lee Fatigue Scale-Short Form and assessed before and after shift. Results A total of 152 RNs (12-hour, n=82; 8-hour, n=70) participated this study, with a mean age of 31.81 (SD= 6.09). Compared with the 8-hour shift nurses, the 12-hour shift nurses were significantly higher in TST (456 vs. 364 minutes), median saliva cortisol level (before day shift, 0.54 vs. 0.31), and median PVT reaction time (before night shift). However, CAR were 0.53 (SD=0.13) and 0.50 (SD=0.18) for 12-hour and 8-hour shift RNs, respectively, and indicates desynchronized CAR in both groups. Regardless shift rotation, almost three-quarters of the RNs had a 500 ms PVT reaction time. For the 12-hour and 8-hour nurses, the level of activity during day shift was similar. However, during night shift work it was significantly lower in 12-hour nurses compared to the 8-hour nurses. All RNs experienced clinical significant fatigue severity (ranged 3.78 to 8.14) regardless before or after shift work; however, the 12-hour group reported lower fatigue severity than 8-hour group. Conclusion In this study, findings revealed shift-work RNs experienced fatigue and desynchronized CAR. The TST was low and reaction time was prolonged before and after shift work. Sleep intervention should be mandatorily included in clinical continue education. Support (if any) This project was supported by Chinese National Natural Science Foundation (71603279).

The courses of objective physical activity and the association with sleepiness during a 2-week-on/2-week-off offshore shift rotation: an observational repeated-measures study

Background Offshore workers are assumed to have poor health behaviours, but no studies have yet examined physical activity (PA) during a full offshore shift rotation period, including both work and at home periods. Furthermore, the relationship of PA with sleepiness, a prevalent safety hazard offshore, is not known. This study aimed to examine (1) the courses of objectively measured PA in offshore workers during pre-, offshore and post-offshore periods, and (2) the association between PA and self-reported sleepiness. Methods An observational repeated measures study was conducted among 36 offshore workers during a full 2-week on/2-week off offshore shift rotation. Objective PA was assessed using Daytime Activity Averages (DAA) from actigraph recordings. Sleepiness was assessed using next-morning Karolinska Sleepiness Scale (KSS) scores. The courses of PA over time were analysed with Linear Mixed Models (LMM). Parallel LMM were used to assess the longitudinal relationship between PA and sleepiness, both on a between-person and within-person level. Results The courses of PA were not significantly different between the pre-, offshore, and post-offshore periods. In addition, between-person trends of PA and sleepiness were not associated (p ranges between 0.08─0.99) and PA did not affect next-morning sleepiness on a within-person level (p = 0.15). Conclusions PA levels during the offshore working period were not different from PA levels at home. Furthermore, PA was not associated with next-morning sleepiness. Further research should focus on different levels of PA including its intensity level.

Association between chronotype and psychomotor performance of rotating shift workers

It is known that the chronotype potentially mediates the performance and tolerance to work in shifts and that shift rotation is associated with negative effects on psychomotor performance. This study aimed to evaluate the effect of chronotype on psychomotor performance throughout a complete shift rotation schedule. Thirty males working in clockwise rotating shifts from a mining company were evaluated under a real-life condition over the following shift schedule: 2 days of day work, 2 days of evening work and 2 days of night work. The chronotype was determined using the Munich Chronotype Questionnaire adapted for shift workers and the obtained scores were categorized by tertiles (early-type, intermediate-type and late-type). Work performance was evaluated by Psychomotor Vigilance Test (PVT) daily just before shift starts and after shift ends. Sleep duration was evaluated by actigraphy over the whole shift. No isolated effect of the shift or interaction between shift and chronotype was found in the performance variables evaluated. A significant isolated effect of the chronotype showed that the early-type individuals had higher values of pre- and post-work Mean of Reaction Time (MRT) (308.77 ± 10.03 ms and 306.37 ± 8.53 ms, respectively) than the intermediate-type (257.61 ± 6.63 ms and 252.91 ± 5.97 ms, respectively, p < 0.001) and the late-type (273.35 ± 6.96 ms and 262.88 ± 6.05 ms, respectively, p < 0.001). In addition, late individuals presented a greater number of lapses of attention (5.00 ± 0.92; p < 0.05) than early (1.94 ± 0.50, p < 0.05) and intermediate (1.33 ± 0.30, p < 0.001) ones. We concluded that, compared with intermediates, late-type workers had a greater number of lapses of attention on the shift schedule as a whole, while early-type workers showed the highest pre- and post-work MRT. These findings show that the psychomotor performance of rotating shift workers seems to be influenced by the chronotype, but not by the shift rotation.

A Goal Programming Approach to Nurse Scheduling with Individual Preference Satisfaction

The use of scheduling optimization tools is essential in creating an efficient nurse shift-rotation schedule. A well-designed nurse scheduling technique can improve nurses’ job satisfaction and their intention to stay. This study develops a goal programming approach to nurse scheduling that simultaneously considers workload fairness and individual preferences on working shift and day off assignments. A case study of an operating room at a hospital in Thailand is used to illustrate the model capabilities for solving an actual nurse scheduling problem. The job satisfaction factors defined based on an interview and questionnaire survey are integrated into the model. When compared against the manual scheduling result, the optimal schedules can be implemented to improve the nurse’s perception of fairness and preference satisfaction. The analysis of fairness and multiple individual preferences based on a case study investigation is the main contribution of this study.

Unravelling the effect of data augmentation transformations in polyp segmentation

Purpose Data augmentation is a common technique to overcome the lack of large annotated databases, a usual situation when applying deep learning to medical imaging problems. Nevertheless, there is no consensus on which transformations to apply for a particular field. This work aims at identifying the effect of different transformations on polyp segmentation using deep learning. Methods A set of transformations and ranges have been selected, considering image-based (width and height shift, rotation, shear, zooming, horizontal and vertical flip and elastic deformation), pixel-based (changes in brightness and contrast) and application-based (specular lights and blurry frames) transformations. A model has been trained under the same conditions without data augmentation transformations (baseline) and for each of the transformation and ranges, using CVC-EndoSceneStill and Kvasir-SEG, independently. Statistical analysis is performed to compare the baseline performance against results of each range of each transformation on the same test set for each dataset. Results This basic method identifies the most adequate transformations for each dataset. For CVC-EndoSceneStill, changes in brightness and contrast significantly improve the model performance. On the contrary, Kvasir-SEG benefits to a greater extent from the image-based transformations, especially rotation and shear. Augmentation with synthetic specular lights also improves the performance. Conclusion Despite being infrequently used, pixel-based transformations show a great potential to improve polyp segmentation in CVC-EndoSceneStill. On the other hand, image-based transformations are more suitable for Kvasir-SEG. Problem-based transformations behave similarly in both datasets. Polyp area, brightness and contrast of the dataset have an influence on these differences.

Pain complaints after consecutive nights and quick returns in Norwegian nurses working three-shift rotation: an observational study

ObjectivesTo determine whether nurses working consecutive night shifts, or short transitions between shifts (quick returns (QRs)), yielded higher risk for pain complaints when compared with regular morning shifts. Sleep duration was tested as a potential mediator.DesignObservational diary study.SettingRandom hospitals.ParticipantsNurses with three-shift rotation (morning, evening and night), n=679, 22–63 years old.Outcomes measuresDaily ratings of working hours, sleep and subjective pain complaints in six anatomical regions (head, neck/shoulder/upper back, upper extremity, low back, lower extremity and abdomen) for 28 days. In addition, we assessed demographics, habitual sleep and pain complaints, work and lifestyle factors. It was tested (1) whether the risk for pain complaints was higher after workday 3 versus after workday 2, and whether the difference was larger for consecutive night shifts versus consecutive morning shifts, and (2) whether the risk for pain complaints was higher after QRs versus after two morning shifts. Risk for pain complaints refers to combined increased risk for any pain and risk for increased intensity.ResultsAdjusted analyses showed no shift type by workday interaction for pain complaints in the neck/shoulder/upper back, upper extremities, low back, lower extremities or abdomen. For headache, a strong trend indicated that the risk was higher on workday 3 compared with workday 2 for night shifts (OR 1.13, 95% CI 0.99 to 1.28). The risk was lowered if sleep duration was taken into account (OR 0.37, 95% CI 0.17 to 0.81). No conclusive support was found for the risk for pain complaints being higher after QRs, compared with after morning shifts.ConclusionsFor five of six pain complaints, the hypotheses were not supported by the current data. For headache, we found potential support for a sleep-relieving effect on headache after working several nights in a row. Pain complaints were not instigated or exacerbated by an evening-to-morning transition between shifts.