Deconstructing dams and disease: predictions for salmon disease risk following Klamath River dam removals

The health of fish populations and the river systems they inhabit have broad ecological, cultural, recreational, and economic relevance. This is exemplified by the iconic anadromous salmonid fishes native to the West Coast of North America. Salmon populations have been constrained since the mid nineteenth century by dam construction and water reallocation. In the Klamath River (Oregon and California, USA), a series of dams built in the early-mid 20th century cut the basin in two and blocked anadromous fish access to more than 600 river kilometers. This dramatic loss of habitat, coupled with infectious diseases and resulting epizootics, have impacted the wellbeing of these salmonid populations. In 2023-2024, the Klamath River will undergo the largest river restoration project in US history. Removal of the four lowermost dams will cause profound physical changes to the river, including flow, water temperature, and channel geomorphology. The dam removals will reconnect the lower and upper portions of the basin, and provide fish passage after a century of segregation. Reestablishment of upstream and downstream fish movements will also alter the occupancy and abundance of the salmonid hosts and their pathogens. The increased habitat availability and longer migration routes will increase duration of pathogen exposure and potential impacts on juvenile survival and adult pre-spawn mortality. However, restoration of more natural flow and sediment regimes will decrease overall fish disease risk by disrupting complex parasite life cycles. To better understand these multifarious, competing factors, we review the salmonid species in the Klamath River, and provide an overview of their historical pathogen challenges and associated diseases and use this as a framework to predict the effects of dam removals on disease dynamics. Our review and predictions are a synthesis of expertise from tribal biologists, fish health specialists and fish biologists, many of whom have lived and worked on the Klamath River for decades. We conclude with recommendations for expansion of current pathogen monitoring and research efforts to measure changes in host-pathogen dynamics basin-wide

American journalism and the landscape of secrecy : Tad Szulc, the CIA and Cuba

The relationship between secret services and the press is an enduring one. Although the CIA did not seek the kind of salient media profile enjoyed by the FBI, it nevertheless maintained an informal press office from its foundation in 1947. Directors of the CIA and their senior staff devoted significant time to the public profile of the Agency. Their efforts to engage with the world of newspapers divided journalists. Some saw it as their patriotic duty to assist the Agency, even reporting for it overseas, while other saw it as their constitutional role to oppose the Agency. This was especially true during the Vietnam War and Watergate. Thereafter, a more nuanced relationship developed in which the press saw themselves as an informal wing of new accountability processes that provided the intelligence community with oversight. This was ambiguous terrain and its complexities are explored here by focusing on the example of the prominent New York Times journalist Tad Szulc, whose complex relationship with the CIA spanned several decades and connected closely with the vexed issue of Kennedy and Cuba. Szulc played a number of roles including outrider, renegade and overseer, but there was confusion about who was servant and who was master

Application of computational fluid dynamics in building performance simulation for the outdoor environment: an overview

This paper provides an overview of the application of CFD in building performance simulation for the outdoor environment, focused on four topics: (1) pedestrian wind environment around buildings, (2) wind-driven rain on building facades, (3) convective heat transfer coefficients at exterior building surfaces, and (4) air pollutant dispersion around buildings. For each topic, its background, the need for CFD, an overview of some past CFD studies, a discussion about accuracy and some perspectives for practical application are provided. The paper indicates that for all four topics, CFD offers considerable advantages compared to wind tunnel modelling or (semi-)empirical formulae because it can provide detailed whole-flow field data under fully controlled conditions and without similarity constraints. The main limitations are the deficiencies of steady RANS modelling, the increased complexity and computational expense of LES and the requirement of systematic and time-consuming CFD solution verification and validation studies