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For the 40 years after the end of commercial whaling in 1976, humpback whale populations in the North Pacific Ocean exhibited a prolonged period of recovery. Using mark-recapture methods on the largest individual photo-identification dataset ever assembled for a cetacean, we estimated annual ocean-basin-wide abundance for the species from 2002 through 2021. Trends in annual estimates describe strong post-whaling era population recovery from 16 875 (± 5955) in 2002 to a peak abundance estimate of 33 488 (± 4455) in 2012. An apparent 20% decline from 2012 to 2021, 33 488 (± 4455) to 26 662 (± 4192), suggests the population abruptly reached carrying capacity due to loss of prey resources. This was particularly evident for humpback whales wintering in Hawai'i, where, by 2021, estimated abundance had declined by 34% from a peak in 2013, down to abundance levels previously seen in 2006, and contrasted to an absence of decline in Mainland Mexico breeding humpbacks. The strongest marine heatwave recorded globally to date during the 2014-2016 period appeared to have altered the course of species recovery, with enduring effects. Extending this time series will allow humpback whales to serve as an indicator species for the ecosystem in the face of a changing climate., Competing Interests: We declare we have no competing interests., (© 2024 The Authors.)

Understanding the migratory patterns of large whales is of conservation importance, especially in identifying threats to specific populations. Migration ecology, including migratory destinations, movements and site fidelity for humpback whales (Megaptera novaeangliae) remain poorly studied in parts of the range of the Central America population, considered endangered under the United States Endangered Species Act. This study aimed to investigate the migratory destinations of humpback whales sighted at two study sites in Nicaragua, which are part of the Central America population. A ten-year photographic database of humpback whales observed off Nicaragua was combined with citizen science contributions and sightings from dedicated research programs. The resulting image collection was compared with available historical photo identifications and databases using an automated image recognition algorithm. This approach yielded 36 years of photographic identification totaling 431 recaptures in Nicaragua (2006-2008 and 2016-2021) and 2539 recaptures (1986-2020) in both feeding and breeding grounds of 176 unique individuals sighted in Nicaragua. Our results showed that photo-identified whales were recaptured between October and April in breeding grounds and year-round in feeding grounds between British Columbia and California, with peak recaptures between June and October. Our study provided first-time evidence on fine-scale site affinity of individual humpback whales within Nicaraguan waters and to other breeding and feeding grounds., (© 2023. Springer Nature Limited.)

The pantropical spotted dolphin in the Eastern Tropical Pacific (ETP) is found in two genetically and phenotypically diverged ecotypes, coastal and offshore. These habitats have distinct acoustic characteristics, which can lead to the evolution of distinct acoustic communication. Whistles are sounds widely used by dolphins to mediate species and individual recognition and social interactions. Here, we study the whistle acoustic structure and repertoire diversity of offshore and coastal pantropical spotted dolphins. Our results show that there is significantly more within- and across-group variation in whistle fundamental frequency between ecotypes than between offshore groups and between coastal groups. A Random Forest classification analysis performed with an accuracy of 83.99% and identified duration, peak and minimum frequency as the most informative variables for distinguishing between ecotypes. Overall, coastal spotted dolphins produced significantly shorter whistles that were significantly lower in frequency (peak, minimum and maximum, and start and end) than offshore dolphins. Ecotypes produced whistle repertoires that were similar in diversity, but different in contour composition, with the coastal ecotype producing more upsweep whistles than offshore dolphins. The results of this study suggest that acoustic adaptations to coastal and offshore environments could be important contributors to intraspecific variation of dolphin whistle repertoires., (© 2023. Springer Nature Limited.)

We present an ocean-basin-scale dataset that includes tail fluke photographic identification (photo-ID) and encounter data for most living individual humpback whales (Megaptera novaeangliae) in the North Pacific Ocean. The dataset was built through a broad collaboration combining 39 separate curated photo-ID catalogs, supplemented with community science data. Data from throughout the North Pacific were aggregated into 13 regions, including six breeding regions, six feeding regions, and one migratory corridor. All images were compared with minimal pre-processing using a recently developed image recognition algorithm based on machine learning through artificial intelligence; this system is capable of rapidly detecting matches between individuals with an estimated 97-99% accuracy. For the 2001-2021 study period, a total of 27,956 unique individuals were documented in 157,350 encounters. Each individual was encountered, on average, in 5.6 sampling periods (i.e., breeding and feeding seasons), with an annual average of 87% of whales encountered in more than one season. The combined dataset and image recognition tool represents a living and accessible resource for collaborative, basin-wide studies of a keystone marine mammal in a time of rapid ecological change., (© 2023. The Author(s).)

A growing number of universities worldwide use various forms of online and blended learning as part of their academic curricula. Furthermore, the recent changes caused by the COVID-19 pandemic have led to a drastic increase in importance and ubiquity of online education. Among the major advantages of e-learning is not only improving students' learning experience and widening their educational prospects, but also an opportunity to gain insights into students' learning processes with learning analytics. This study contributes to the topic of improving and understanding e-learning processes in the following ways. First, we demonstrate that accurate predictive models can be built based on sequential patterns derived from students' behavioral data, which are able to identify underperforming students early in the course. Second, we investigate the specificity-generalizability trade-off in building such predictive models by investigating whether predictive models should be built for every course individually based on course-specific sequential patterns, or across several courses based on more general behavioral patterns. Finally, we present a methodology for capturing temporal aspects in behavioral data and analyze its influence on the predictive performance of the models. The results of our improved sequence classification technique are capable to predict student performance with high levels of accuracy, reaching 90% for course-specific models., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2022 Elsevier Ltd. All rights reserved.)

Healthcare organizations are confronted with challenges including the contention between tightening budgets and increased care needs. In the light of these challenges, they are becoming increasingly aware of the need to improve their processes to ensure quality of care for patients. To identify process improvement opportunities, a thorough process analysis is required, which can be based on real-life process execution data captured by health information systems. Process mining is a research field that focuses on the development of techniques to extract process-related insights from process execution data, providing valuable and previously unknown information to instigate evidence-based process improvement in healthcare. However, despite the potential of process mining, its uptake in healthcare organizations outside case studies in a research context is rather limited. This observation was the starting point for an international brainstorm seminar. Based on the seminar's outcomes and with the ambition to stimulate a more widespread use of process mining in healthcare, this paper formulates recommendations to enhance the usability and understandability of process mining in healthcare. These recommendations are mainly targeted towards process mining researchers and the community to consider when developing a new research agenda for process mining in healthcare. Moreover, a limited number of recommendations are directed towards healthcare organizations and health information systems vendors, when shaping an environment to enable the continuous use of process mining., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: The HIV epidemic exacerbated the prevalence of prime-aged adult death in many parts of sub-Saharan Africa, resulting in increased rates of orphanhood. Little is known about whether this will coincide with adverse psychosocial well-being in adulthood for those who were orphaned at childhood., Methods: We studied a cohort of 1108 children from Kagera, a region of Tanzania that was heavily affected by HIV early in the epidemic. During the baseline data collection in 1991-1994, these children were aged 0-16 years and had both parents alive. We followed them roughly 16-19 years later in 2010, by which time 531 children (36%) had lost either one or both parents before their 19th birthday. We compared the 2010 10-item Rosenberg Self-Esteem Scale (RSES) score between children who lost a parent before the age of 19 and those who did not. We used the baseline data to control for preorphanhood confounders. This is important because we find that children who will lose their fathers in the future before age 19 came from somewhat lower socioeconomic backgrounds., Results: We found no correlation between maternal death and self-esteem measured through RSES. Paternal death was strongly correlated with lower levels of self-esteem (0.2 SDs lower RSES 95% confidence interval: 0.059 to 0.348), and the correlation was stronger when the death occurred during the child's teenage years. These effects are a net of socioeconomic differences that existed before the orphanhood event., Conclusions: Our study supports the further development and piloting of programs that address psychosocial problems of orphans.

The care processes of healthcare providers are typically considered as human-centric, flexible, evolving, complex and multi-disciplinary. Consequently, acquiring an insight in the dynamics of these care processes can be an arduous task. A novel event log based approach for extracting valuable medical and organizational information on past executions of the care processes is presented in this study. Care processes are analyzed with the help of a preferential set of process mining techniques in order to discover recurring patterns, analyze and characterize process variants and identify adverse medical events., (© 2013 Elsevier Ltd. All rights reserved.)

This article presents unique evidence that orphanhood matters in the long run for health and education outcomes in a region of northwestern Tanzania. We study a sample of 718 non-orphaned children surveyed in 1991-1994 who were traced and reinterviewed as adults in 2004. A large proportion, 19%, lost one or more parents before age 15 in this period, allowing us to assess permanent health and education impacts of orphanhood. In the analysis, we control for a wide range of child and adult characteristics before orphanhood, as well as community fixed effects. We find that maternal orphanhood has a permanent adverse impact of 2 cm of final height attainment and one year of educational attainment. Expressing welfare in terms of consumption expenditure, the result is a gap of 8.5% compared with similar children whose mothers survived until at least their 15th birthday.

Background: In sub-Saharan Africa, the prevalence of orphanhood among children has been greatly exacerbated by the HIV/AIDS pandemic. If orphanhood harms a child's development and these effects perpetuate into adult life, then the African orphan crisis could seriously jeopardize the continent's future generations. Whether or not there exists an adverse, causal and intergenerational effect of HIV/AIDS on development is of crucial importance for setting medical priorities. This study is the first to empirically investigate the impact of orphanhood on health and schooling using long-term longitudinal data following children into adulthood., Methods: We examined a cohort of 718 children interviewed in the early 1990s and again in 2004. Detailed survey questionnaires and anthropometric measurements were administered at baseline and during a follow-up survey. Final attained height and education (at adulthood) between children who lost a parent before the age of 15 and those who did not were compared., Results: On average, children who lose their mother before the age of 15 suffer a deficit of around 2 cm in final attained height (mean 1.96; 95% CI 0.06-3.77) and 1 year of final attained schooling (mean 1.01; 95% CI 0.39-1.81). This effect is permanent and the hypothesis that it is causal cannot be rejected by our study. Although father's death is a predictor of lower height and schooling as well, we reject the hypothesis of a causal link., Conclusions: The African orphan crisis, exacerbated by the HIV/AIDS epidemic will have important negative intergenerational effects.

Rigorous empirical research on the socioeconomic effects of AIDS is important for developing appropriate strategies to mitigate impacts and ultimately improve living standards. This paper provides a broad overview of the challenges in studying the impact of the epidemic on individuals, households and economies, drawing examples from existing studies. We start with a discussion of macro-economic studies and argue that they reach vastly different conclusions about the impact of AIDS, depending on what parameter assumptions they make. Whereas microstudies could provide insights into some of these parameters and effects, there are many technical hurdles to overcome. We discuss the use of comparator groups, spillover effects, longitudinal datasets and the time horizons of studies. Under scrutiny of these technical requirements, the existing empirical evidence of the impoverishing effects of AIDS deaths on African households seems unexpectedly limited. After many years of study, large gaps remain in the empirical literature with regard to our understanding of the magnitude and heterogeneity of these impacts. We conclude that the literature thus far has not convincingly shown that AIDS is the main contributor to low levels and high inequities of socioeconomic outcomes in Africa. Demand for research on the causal impact of HIV/AIDS on poverty is only increasing with the scaling up of antiretroviral treatment.

Unlabelled: Perinatal exposure to Dutch background dioxin levels is rather high. Studies of calamities have shown that dioxins negatively influence the respiratory system. It was hypothesized that perinatal exposure to background dioxin levels leads to lung suboptimality, probably through developmental interference. This study aimed to assess lung function in relation to perinatal dioxin exposure. Spirometry was performed in 41 healthy children (aged 7-12 y. mean 8.2 y) with known perinatal dioxin exposure. The ratio of forced expiratory volume in I s to forced vital capacity (FEV1/FVC ratio) was determined. A complete medical history was taken. The prenatal exposure ranged from 8.74 to 88.8 (mean 34.6) ng TEQ dioxin kg fat(-1), measured in breast milk. The postnatal exposure ranged from 4.34 to 384.51 (mean 75.4) ng TEQ dioxin. Twelve children had to be excluded. A significant decrease in lung function in relation to both prenatal (p = 0.045) and postnatal (p = 0.0002) dioxin exposure was seen in the 29 non-excluded children. A clinical association between chest congestion and perinatal dioxin exposure was seen., Conclusion: Perinatal background dioxin exposure may be inversely associated with the FEV1/ FVC ratio.

A clindamycin-resistant toxin A-negative, toxin B-positive Clostridium difficile strain caused an outbreak among 24 hospitalized patients at the Department of Surgery, the Intensive Care unit, and the Department of Internal Medicine of an 800-bed academic hospital. Nineteen patients had undergone a surgical intervention and all 24 patients received at least one dose of antibiotics prior to the development of Clostridium difficile-associated diarrhoea. Twenty-seven episodes of Clostridium difficile-associated diarrhoea in 24 patients were categorized as mild (n=19), severe (n=7), or fatal (n=1). Relapses occurred in three patients. Nineteen of the 27 episodes required anti-Clostridium difficile treatment. Molecular typing performed by arbitrary primer polymerase chain reaction (PCR) and PCR amplification of rRNA intergenic spacer regions revealed that the outbreak strains recovered from culture were identical. The outbreak strain belonged to serogroup F and was resistant to erythromycin, clindamycin, and tetracycline, whereas susceptibility to chloramphenicol varied. No phenotypic activity of enterotoxin A was detected. A deletion of approximately 1.7 kb was found in the toxin A gene. Cytotoxin B had an unusual effect on cell culture assays that, at first, was not recognized as Clostridium difficile specific but could be neutralized with anti-Clostridium difficile B cytotoxin.