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Amos, C.L.; Kassem, H.; Petrie, B.; Shaw, J., and Ivaldi, R., 2024. An evaluation of the Bagnold (1956) theories for sediment transport in Northumberland Strait, Canada. Journal of Coastal Research, 40(6), 1019–1036. Charlotte (North Carolina), ISSN 0749-0208. This study examines the seabed stability and sediment transport in the region of a proposed fixed link (bridge) across Northumberland Strait, Canada. The region is dominated by strong semidiurnal and diurnal tides that have eroded, transported, and deposited material that modify the character of the local seabed morphology. The seabed comprises rippled fine sand interspersed with a shelly gravel lag. The study provides an opportunity to examine the theories of R.A. Bagnold on sand transport that were deficient in the prediction of the transport of fine and very fine sand. A further purpose was to determine the mechanisms of the sand transport (waves, currents, or both). Representative sediment samples were collected and subjected to hydrodynamic forcing in a laboratory flume (Lab Carousel); relationships were derived between the applied stream power and sediment transport rates as bedload and in suspension. In addition, a multiparameter benthic lander (Ralph) was deployed at two sites in the nearshore regions of the fixed link for a total duration of 33 days. Flow velocity measurements derived from the lander were used to assess the transport potential using calibrations derived from the flume studies. The results showed that the total immersed bedload transport measured herein corresponded well to Bagnold's dimensionless stream power function when normalized to flow depth and grain size. They also showed that the tidal currents coupled with the mean flow in the region are sufficient in magnitude to erode and transport sand to the SE, where they are deposited to form a tidal delta. The sand transport in the shallow margins (depth < 10 m) took place mainly as bedload, although periodic suspension also took place. The nature of the predicted sand transport indicates that the seabed is in a continued state of evolution subject to the present-day hydrodynamic forcing. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examined the outcomes of patients with gallbladder cancer over 20 years in Saskatchewan, Canada, focusing on geographic, demographic, and clinical factors. A total of 331 patients diagnosed between 2000 and 2019 were included. The majority (64%) had advanced stage 4 disease, with a significant proportion (66%) being rural residents. Key factors associated with poorer overall survival included stage 4 disease, lack of surgery, older age, a higher neutrophil-to-lymphocyte ratio, and no referral to a regional cancer center. Among early-stage patients, stage III disease and urban residence were associated with worse disease-free survival. The findings highlight the late-stage diagnosis and referral challenges impacting the outcomes of gallbladder cancer. Background: Gallbladder cancer (GBC) is an uncommon cancer. This study aimed to determine the outcomes of GBC in relation to geographic, demographic, and clinical factors in a Canadian province from 2000 to 2019. Methods: This population-based retrospective cohort study included all patients diagnosed with gallbladder cancer (GBC) in Saskatchewan, Canada, from 2000 to 2019. Cox proportional multivariate regression analysis was conducted to identify factors associated with poorer outcomes. Results: In total, 331 patients with a median age of 74 years and male–female ratio of 1:2 were identified. Of these patients, 305 (92%) had a pathological diagnosis of GBC. Among patients with documented staging data, 64% had stage IV disease. A total of 217 (66%) patients were rural residents, and 149 (45%) were referred to a cancer center. The multivariate analysis for patients with stage I–III GBC showed that stage III disease [hazard ratio (HR), 2.63; 95% confidence interval (CI), 1.09–6.34)] and urban residence (HR, 2.20; 95% CI, 1.1–4.39) were correlated with inferior disease-free survival. For all patients, stage IV disease (HR, 3.02; 95% CI, 1.85–4.94), no referral to a cancer center (HR, 2.64; 95% CI, 1.51–4.62), lack of surgery (HR, 1.63; 95% CI, 1.03–2.57), a neutrophil–lymphocyte ratio of >3.2 (HR, 1.57; 1.05–2.36), and age of ≥70 years (HR, 1.51; 95% CI, 1.04–2.19) were correlated with inferior overall survival. Conclusions: In this real-world context, the majority of patients with GBC were diagnosed at a late stage and were not referred to a cancer center. For those with early-stage GBC, living in an urban area and having stage III disease were linked to worse outcomes. Across all stages of GBC, stage IV disease, older age, absence of surgery, lack of referral to a cancer center, and a high neutrophil-to-lymphocyte ratio were associated with poorer survival. [ABSTRACT FROM AUTHOR]

Given the importance of climate in shaping species' geographic distributions, climate change poses an existential threat to biodiversity. Climate envelope modeling, the predominant approach used to quantify this threat, presumes that individuals in populations respond to climate variability and change according to species-level responses inferred from spatial occurrence data--such that individuals at the cool edge of a species' distribution should benefit from warming (the "leading edge"), whereas individuals at the warm edge should suffer (the "trailing edge"). Using 1,558 tree-ring time series of an aridland pine (Pinus edulis) collected at 977 locations across the species' distribution, we found that trees everywhere grow less in warmer-than-average and drier-than-average years. Ubiquitous negative temperature sensitivity indicates that individuals across the entire distribution should suffer with warming--the entire distribution is a trailing edge. Species-level responses to spatial climate variation are opposite in sign to individual-scale responses to time-varying climate for approximately half the species' distribution with respect to temperature and the majority of the species' distribution with respect to precipitation. These findings, added to evidence from the literature for scale-dependent climate responses in hundreds of species, suggest that correlative, equilibrium-based range forecasts may fail to accurately represent how individuals in populations will be impacted by changing climate. A scale-dependent view of the impact of climate change on biodiversity highlights the transient risk of extinction hidden inside climate envelope forecasts and the importance of evolution in rescuing species from extinction whenever local climate variability and change exceeds individual-scale climate tolerances. [ABSTRACT FROM AUTHOR]

The text discusses two books: "Murder at the Mission: A Frontier Killing, Its Legacy of Lies, and the Taking of the American West" by Blaine Harden, and "Leveraging an Empire: Settler Colonialism and the Legalities of Citizenship in the Pacific Northwest" by Jacki Hedlund Tyler. "Murder at the Mission" examines the story of Marcus Whitman and the Cayuse people in Oregon Territory, debunking the myth that Whitman saved Oregon from the British. "Leveraging an Empire" explores how Oregon's territorial laws and admission to statehood shaped national decisions on issues such as slavery, immigration, and citizenship. Both books provide valuable insights into the history of the American West and challenge popular narratives. [Extracted from the article]

The Frank-Starling law and Anrep effect describe two intrinsic mechanisms that regulate contraction force in the heart. Based on recent advancements and the historical literature, we propose new perspectives and address several critical issues in this review. ( a ) The Frank-Starling mechanism and Anrep effect are dynamically linked and act synergistically. ( b ) An open question is how cardiomyocytes sense mechanical load and transduce to biochemical signals (called mechano-chemo-transduction or MCT) to regulate contraction in response to load changes. ( c ) One research focus is to identify various mechanosensors and decipher their downstream MCT pathways. ( d ) Innovative experimental techniques engage different mechanosensors that detect different local strain and stress in the cell architecture. ( e ) Closed-loop MCT feedback in the dynamic excitation-Ca2+ signaling-contraction system enables autoregulation of contraction in response to physiological load changes. (  f  ) However, pathological overload such as volume and pressure overload lead to excessive MCT-Ca2+ gain, cardiac remodeling, and heart diseases.

Adaptive transport networks are known to contain loops when subject to hydrodynamic fluctuations. However, fluctuations are no guarantee that a loop will form, as shown by loop-free networks driven by oscillating flows. We provide a complete stability analysis of the dynamical behavior of any loop formed by fluctuating flows. We find a threshold for loop stability that involves an interplay of geometric constraints and hydrodynamic forcing mapped to constant and fluctuating components. Loops require fluctuation in the relative size of the flux between nodes, not just a temporal variation in the flux at a given node. Hence, there is both a minimum and a maximum amount of fluctuation relative to the constant-flux component where loops are supported.