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Corporate tourism threatens protected areas
No full textRapidly expanding tourism infrastructure within protected areas—particularly new camps, lodges, and hotels—undermines biodiversity conservation and Indigenous peoples’ rights. The Ritz-Carlton, Masai Mara Safari Camp in Kenya’s Maasai Mara National Reserve, a United Nations Educational, Scientific, and Cultural Organization (UNESCO) tentative site and home to the Great Wildebeest Migration Route, exemplifies this threat
Variational autoencoder-based deep learning and radiomics for predicting pathologic complete response to neoadjuvant chemoimmunotherapy in locally advanced esophageal squamous cell carcinoma
No full textOBJECTIVES: Neoadjuvant chemoimmunotherapy (nCIT) is gradually becoming an important treatment strategy for patients with locally advanced esophageal squamous cell carcinoma (LA-ESCC). This study aimed to predict the pathological complete response (pCR) of these patients using variational autoencoder (VAE)-based deep learning and radiomics technology. METHODS: A total of 253 LA-ESCC patients who were treated with nCIT and underwent enhanced CT at our hospital between July 2019 and July 2023 were included in the training cohort. VAE-based deep learning and radiomics were utilized to construct deep learning (DL) models and deep learning radiomics (DLR) models. The models were trained and validated via 5-fold cross-validation among 253 patients. Forty patients were recruited from our institution between August 2023 and August 2024 as the test cohort. RESULTS: The AUCs of DL and DLR model were 0.935 (95% CI: 0.786-0.992) and 0.949 (95% CI: 0.910-0.986) in the validation cohort and 0.839 (95% CI: 0.726-0.853), 0.926 (95% CI: 0.886-0.934) in the test cohort. The performance gap between Precision and Recall of the DLR model was smaller than that of DL model. The F1 scores of the DL and DLR model were 0.726 (95% confidence interval [CI]: 0.476-0.842) and 0.766 (95% CI: 0.625-0.842) in the validation cohort and 0.727 (95% CI: 0.645-0.811), 0.836 (95% CI: 0.820-0.850) in the test cohort. CONCLUSIONS: We constructed a DLR model to predict pCR in nCIT treated LA-ESCC patients, which demonstrated superior performance compared to the DL model. ADVANCES IN KNOWLEDGE: We innovatively used VAE-based deep learning and radiomics to construct the DLR model for predicting pCR of LA-ESCC after nCIT
Pain-related variables as contributing factors to physical activity after breast cancer surgery:a one-year follow-up study
No full textPhysical activity (PA) levels among breast cancer survivors following surgery are often low, with unclear roles played by pain-related factors. This study investigates the changes in PA and its contributing factors, including pain-related factors, in 184 breast cancer survivors throughout the acute post-operative stage of 1 week (T1), the sub-acute stage of 4 months (T4), and the long-term stage of 12 months (T12). A linear mixed model was utilized to evaluate PA changes in the first year post-surgery. Multivariate regression analyses explored associations between moderate-to-vigorous physical activity (MVPA) and patient characteristics, pain-related factors, emotional and physical functioning, and quality of life (QoL) at each timepoint separately and also explored factors in the acute and sub-acute stage contributing to MVPA at T12. Weekly minutes of MVPA and steps had a significant increase between T4 and T12. All models, adjusted for age and BMI, were significant (p < 0.01) but explained only small proportions of variance of MVPA at T1 (AdjR 2 :15%), at T4 (AdjR 2 :25%) and at T12 (AdjR 2 :26%). Pain-related factors, together with emotional and physical symptom burden, negatively impacted PA at various points in time. Despite these challenges, higher QoL and existential well-being were positive influences. Breast cancer survivors demonstrate increasing PA over the first year post-surgery. Contributing factors differ for each timepoint, highlighting the complex interplay of emotional and physical factors in promoting active lifestyles. Rehabilitation interventions need to hold the time-dependency of contributing factors into account and aim to address both immediate and long-term needs.</p
Numbers Ain't Neutral:A QuantCrit Analysis of the Relationship Among Stereotype Threat, Threat Mitigation, and Identity Safety
No full textPurpose Stereotype threat (fear of fulfilling negative stereotypes about one's group) hinders performance through mechanisms such as overwhelming working memory and forcing conscious attention to normally automated cognitive or physical processes. Efforts to combat stereotype threat may include threat mitigation (reactive responses to identity threats) and identity safety (proactively empowering individuals to be their authentic selves). The authors assessed the relationship among stereotype threat, threat mitigation, identity safety, and participant demographics. Method In this cross-sectional study, all U.S. nephrology fellows were invited to complete a survey after the 2024 national in-training examination. The study was anchored in QuantCrit, a research paradigm that applies critical race theory to quantitative methods, and included 8 items using a 5-point Likert scale. The authors performed confirmatory factor analysis to explore statistical validity for the proposed model. Exploring stereotype threat as the dependent variable, the authors compared non-QuantCrit with QuantCrit analysis. Results Overall, 646 of 962 fellows responded (66.9% response rate). With confirmatory factor analysis, a 3-factor model achieved best fit. Participants endorsed low stereotype threat (mean [SD], 1.47 [0.87]), moderate threat mitigation (mean [SD], 3.02 [1.25]), and high identity safety (mean [SD], 4.34 [0.81]). In non-QuantCrit and QuantCrit regressions, threat mitigation was positively associated with stereotype threat, whereas identity safety was inversely associated with stereotype threat. Non-QuantCrit analysis showed no identity-based differences in stereotype threat. QuantCrit analysis with disaggregated identity categories showed that Southeast Asian and Black fellows and international medical graduates (IMGs) from Asia and the Middle East had higher stereotype threat. Asian and Black fellows who were IMGs had less stereotype threat than their racial counterparts from U.S. allopathic schools. Conclusions Fellows who experienced more identity safety reported less stereotype threat, whereas fellows who experienced more threat mitigation reported more stereotype threat. QuantCrit analysis demonstrated intergroup differences not apparent in non-QuantCrit analysis
Coconvex characters on collections of phylogenetic trees
No full textIn phylogenetics, a key problem is to construct evolutionary trees from collections of characters where, for a set X of species, a character is simply a function from X onto a set of states. In this context, a key concept is convexity, where a character is convex on a tree with leaf set X if the collection of subtrees spanned by the leaves of the tree that have the same state are pairwise disjoint. Although collections of convex characters on a single tree have been extensively studied over the past few decades, very little is known about coconvex characters, that is, characters that are simultaneously convex on a collection of trees. As a starting point to better understand coconvexity, in this paper we prove a number of extremal results for the following question: What is the minimal number of coconvex characters on a collection of n-leaved trees taken over all collections of size t=2, also if we restrict to coconvex characters which map to k states? As an application of coconvexity, we introduce a new one-parameter family of tree metrics, which range between the coarse Robinson-Foulds distance and the much finer quartet distance. We show that bounds on the quantities in the above question translate into bounds for the diameter of the tree space for the new distances. Our results open up several new interesting directions and questions which have potential applications to, for example, tree spaces and phylogenomics
Large-scale computed tomography study of aortic arch and supra-aortic artery morphology:Variations and potential implications for arterial extracorporeal life support access
No full textBackground: The anatomy and morphology of the aortic arch and its supra-aortic arteries can vary significantly among individual patients. This variability may have a particular relevance in cardiovascular procedures or interventions, and specifically during the use of mechanical circulatory support. This importance accounts for a specific influence on hemodynamics in veno-arterial extracorporeal membrane oxygenation (V-A ECMO) through an axillary/subclavian artery access. The related hemodynamic effects and interplay with native cardiac blood flow dynamics have been poorly investigated. Methods: To assess the existing patterns of aortic arch and related supra-aortic artery morphology, thoracic computed tomography (CT) scans of patients undergoing pre-procedural (trans-catheter aortic valve or aortic or other cardiovascular surgery) assessment were investigated. All CT scans clearly showing the thoracic aorta in all its anatomical parts were selected and evaluated in terms of anatomical features (aortic arch type, position of the supra-aortic arteries along the aortic arch or ascending aorta, length and disposition of the ascendent aorta and aortic valve plane, and descending thoracic aorta). Aortic arch morphology was classified according to the Madhwal description, 1namely Type I, II, and III based on the exit point of the left subclavian artery along the aortic arch, with Type III configuration with all the three supra-aortic arteries departing leftwards the aortic arch peak, and Type I presenting the left subclavian artery departing from the peak of the aortic arch. Results: The CT scans of 1228 patients were analyzed and categorized. Overall, 70% (860 cases) of the aortic arch were Type III, 16.9% (208 cases) Type II, and 8.4% (103 cases) Type I. No difference was found between male and female patients. Type III aortic arch morphology presents a potentially unfavorable relationship due to a retrograde flow from the right axillary or subclavian artery, in case of such a V-A ECMO perfusion access, allegedly towards/against the aortic valve and left ventricular ejection. Type I and II aortic arch morphology showed patterns potentially more favorable from a mechanistic point of view, with an apparent more favorable anatomical disposition for a blood flow mainly directed towards the descending aorta. Conclusions: Aortic arch and supra-aortic artery morphology vary markedly among patients. However, in this large patient population, the majority of aortic arch morphology was Type III which has a potentially unfavorable interaction between the native blood flow and V-A ECMO retrograde flow from the right axillary/subclavian artery compared to the left-sided access. Dedicated fluid-dynamic studies investigating the actual right or left axillary artery-generated retrograde flow direction and distribution along the ascending aorta, aortic arch and descending aorta deserves further investigation. Indeed, the interplay of blood flows generated by the left ventricle and that of V-A ECMO perfusion from right or left axillary/subclavian arteries and the consequence of this interplay on oxygen mixing, delivery and LV afterload, are warranted due to the increased use of such an approach.</p
Unsupervised machine learning to explore inflammation following cardiopulmonary bypass
No full textIntroduction: Cardiac surgery with cardiopulmonary bypass (CPB) often induces systemic inflammatory reaction syndrome (SIRS), affecting postoperative outcome. We aimed to explore adaptive/maladaptive inflammation using unsupervised machine learning. Methods: We conducted a post hoc analysis of 1908 adult patients who underwent elective cardiac surgery with CPB between June 2016 and June 2020 at a single institution. Patients were assessed for SIRS 12 hours post-surgery and clustered using the partitioning around medoids (PAM) algorithm based on Gower distance. The influence of SIRS on a composite outcome comprising death, stroke/TIA, renal replacement therapy, reoperation for bleeding, mechanical circulatory support, and ICU stay >96 hours was analyzed via multivariable logistic regression. Results: SIRS occurred in 28.7% of patients (median age 69 years; 68.7% male). Clustering revealed two subgroups: maladaptive SIRS (52.9%) with higher preoperative risk and worse outcomes, and adaptive SIRS (47.1%) with favorable outcomes. Maladaptive SIRS patients had higher 30-day mortality (21.7% vs 1.6%, p < .001). Adaptive SIRS patients had outcomes similar to SIRS-negative controls. In selected clusters, SIRS was independently associated with a lower risk of the composite outcome (OR 0.44; 95% CI 0.26-0.74, p = .002). Conclusion: Unsupervised machine learning effectively identifies adaptive and maladaptive SIRS in cardiac surgery patients, providing a basis for personalized postoperative care. Several clinical and procedural factors associated with maladaptive SIRS may be modifiable, supporting future precision strategies to reduce harmful inflammation after cardiac surgery.</p
The art of inquiring:examining the quality of adult eyewitness interviews in the Netherlands
No full textEyewitness interviews are critical to police investigations. The Generic Witness Interview, used by Dutch police, aligns with best practices to enhance accurate recall. However, research on its implementation is scarce, and existing studies indicate that Dutch police frequently use inappropriate questions, deviating from guidelines. We assessed the quality of 103 real-life Dutch eyewitness interviews to evaluate questioning strategies and adherence to the Generic Witness Interview. We also examined whether investigators probed witnesses about factors that can impair eyewitness accuracy. Most of the questions used were appropriate (69%), with probing questions being most prevalent. Inappropriate questions (31%) mostly consisted of closed questions, while suggestive and forced-choice questions were rare. Yet, interviewers frequently missed opportunities to inquire about factors that can impair eyewitness accuracy (84%). These findings suggest that while Dutch police generally adhere to best practices, further training is recommended. Policy implications for police training and interview standardization are discussed
UCI Sports Nutrition Project:Nutritional Periodization
No full textThe fundamental goal of nutrition for training is to provide the required energy and substrate to sustain the target training volume and intensity that is necessary to induce desired physiological adaptations. However, aside from fueling and recovery, it is now recognized that nutrient availability also modulates the activation of cell signaling pathways that regulate adaptations associated with both endurance and strength training. Such developments are the guiding principles underpinning "nutritional periodization" wherein energy, macronutrient, and micronutrient availability are deliberately manipulated across the microcycle, mesocycle, and macrocycle with the strategic goal to promote training adaptations, support recovery, manipulate body composition, and optimize competition performance. In addition to total "daily" nutrient intake, the elite athlete must, therefore, adjust their energy and carbohydrate intake in a meal-by-meal and day-by-day manner (i.e., carbohydrate periodization) in accordance with the energetic demands and training objectives of each specific training session. In addition to fueling (and refueling) for the work required, daily protein intake should at least be 1.6-2.1 g<middle dot>kg-1<middle dot>day-1 not only to account for amino acid oxidation during exercise but also, importantly, to promote tissue remodeling, notably skeletal muscle. Emerging evidence also supports the rationale for nutraceuticals to promote recovery and sleep, though the potential effect of such compounds in blunting training adaptation should also be considered. Taken together, it is increasingly clear that nutrition is a critical enabler to successful training outcomes, and as such, the sport nutritionist should be considered an integral member of an athlete's coaching and performance support team
Determining fair medicines prices. What do citizens think?
No full textObjectives: There is a lively debate about the fair price of medicines, mainly led by experts. Little is known about the public's opinion, although in most health systems with universal coverage medicines are procured by public money through payers or governments. This study assesses public opinion about fair medicine prices, the criteria that define fairness, and the policy implications. Methods: A population survey amongst 1000 people across the Swiss population in all 3 language regions has been conducted between September and October 2024. Results: Access for all (986), transparency of the cost structure (914) and a price reflecting the costs of a medicine (911) have ranked as the most relevant factors for a fair price of medicine. In contrast, the additional benefit of a new therapy is considered less important as a criterion. A large majority supports pharmaceutical companies making a profit. Asked how to align the different objectives, the majority supports the statement that medicines prices should be the result of a fair process (568), followed by the statement that governments should control profits (431). Conclusions: This study suggests that citizens consider the balance between patient access and investment in research and development as the most relevant for a fair price of a medicine. When access and cost create a dilemma, citizens favour fair procedures. In contrast to expert opinions, the additional benefit of a medicine seems to be a less relevant criterion. The survey results indicate a nuanced and pragmatic approach to fairness, considering societal, scientific, and economic factors