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Four Southern British Columbian Chinook Salmon (SBCC) (Oncorhynchus tshawytscha) Designatable Units (DU) were assessed as Threatened or Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2020 and are currently under consideration for addition to Schedule 1 of the Species at Risk Act (SARA). The first half of the Recovery Potential Assessment (RPA) (Elements 1-11) first provides descriptions and status updates for the populations, an overview of biology and habitat requirements, and an assessment of the threats and factors limiting recovery. The major threats impacting DUs were assessed in a workshop with local experts and were determined to be climate change, natural system modifications, fishing, and pollution. All four DUs are considered to be at an extreme threat risk due to the severity and number of threats these DUs are facing. Based on the assessed threats, a population level decline of 71% to 100% is expected for DUs 1, 6, 13 and 15. Alleviating the multiple and complex threats to these DUs will be difficult, especially as many of the threats are exacerbated by climate change. The second half (Elements 12-22) provides potential recovery targets, a discussion of mitigation measures, population projections and a recommendation of allowable harm. Survival and recovery targets for each DU were suggested based on Wild Salmon Policy (WSP) benchmarks, with additional requirements about observed percent change in spawners. Data limitations from incomplete escapement coverage and unknown hatchery influences prevented many quantitative assessments and no modelling was completed. The risks imposed by climate change and continued anthropogenic development add additional uncertainty that was only described qualitatively. Based on the qualitative assessment for all four DUs, further harm may continue to jeopardize recovery. Therefore, to promote the survival and recovery of these DUs, it is recommended that all future and ongoing human-induced harm should be prevented so as not to jeopardize recovery. It is important to note that some activities in support of survival or recovery could result in harm but may have a net positive effect on the population and should be considered. [ABSTRACT FROM AUTHOR]

The application of liquid-phase synthesis with solid-phase workup to multistep and combinatorial syntheses was examined in a quinoline precipitation device. The results suggested that the quinoline precipitation device offers normal organic compound solubility in the neutral state, but very high insolubility as the bisulfate salt. This feature plus its low molecular weight makes it possible to handle quinoline intermediates exactly like any other organic intermediate. Moreover, it also offers the advantages of solid-phase workup upon treatment with sulfuric acid.

Eleven Designatable Units (DUs) of Chinook Salmon (Oncorhynchus tshawytscha), within the Fraser River were assessed as Threatened or Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2018, and are currently under consideration for addition to Schedule 1 of the Species at Risk Act (SARA). The first part of the Recovery Potential Assessment (RPA) (Elements 1-11) provided DU descriptions, status updates and an assessment of the threats and factors limiting recovery. This second half provides potential recovery targets, a discussion of mitigation measures, population projections and a recommendation on allowable harm. Survival and recovery targets for each DU were suggested based on Wild Salmon Policy (WSP) benchmarks, with additional requirements about observed percent change in spawners. A projection model was used to assess likely future trajectories and the chances of meeting these targets, however, results are only available for DU2 (LFRHarrison). Despite efforts to produce the required input parameters for the stream-type DUs, significant uncertainties and a considerable lack of data prevented quantitative assessment, and hence these DUs were assessed qualitatively. Results for DU2 (LFR-Harrison) indicate that reaching the survival target under recent conditions is about as likely as not likely (48% chance), while meeting the recovery goal is unlikely (16% chance). Risks imposed by climate change and continued anthropogenic development add additional uncertainty that was only described qualitatively. Based on the quantitative assessment for DU2 (LFR-Harrison) and the qualitative assessment for the remaining DUs, it is recommended that human-induced mortality and other sources of harm identified in the threats assessment should be significantly reduced and in some cases prevented to provide the best chance for these populations to recover. [ABSTRACT FROM AUTHOR]

Six oxidized derivatives of MK-0476 (Montelukast or L-706631) were synthesized in an attempt to identify and characterize the regiochemistry of its oxidative metabolites. Specifically, three diastereomeric pairs proposed to be oxidative metabolites of the orally active cys-leukotriene D4 receptor antagonist were prepared. Two of these were 1,2-diols and sulfoxides. The latter were obtained via direct oxidation of MK-0476 with m-chlorperbenzoic acid.

The diarylpropane intermediate in the synthesis of LTD(sub 4) antagonists L-691,698 and L-699,392 can be prepared by coupling and selective enone reduction. The coupling reaction is Claisen-Schmidt condensation. Later the quinoline heterocycle is joined to these intermediates by either alkylation or Heck coupling. This methodology depends on the bridge to the 7-chloroquinaldine moiety. The inversion of the phenol at the chiral center completes the synthesis of L-691,698. Mannich reaction and Hofmann elimination are the two final steps to prepare L-699,392.

A new protease, apopin, appears responsible for poly(ADP-ribose) polymerase's proteolytic breakdown which is essential for the onset of apoptosis. Apopain is derived from CPP-32, a common proenzyme, and contains two subunits that have relative molecular masses of (Mr)17K and 12K. In vitro and in vivo apoptosis is prevented when the active form of the specific interleukin-1beta-converting (ICE)/CED-3-like cystine protease, CPP-32, is inhibited.

Eleven Fraser River Chinook Salmon (FRC) (Oncorhynchus tshawytscha) Designatable Units (DU) were assessed as Threatened or Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) in 2018, and are currently under consideration for addition to Schedule 1 of the Species at Risk Act (SARA). This first part of the Recovery Potential Assessment (RPA) (Elements 1-11) provides descriptions and status updates for the populations, an overview of biology and habitat requirements, and an assessment of the threats and factors limiting recovery. The major threats impacting DUs were assessed in a workshop with local experts, and were determined to be climate change, natural system modifications, fishing, and pollution. Threats to individual DUs of note include: recent landslides posing serious risks to DUs 8, 9, 10 and 11; competition with hatchery fish for DU2; and particularly high impacts due to natural systems modifications for DUs 9 and 14. All eleven DUs are considered to be at a high-extreme or extreme threat risk, due to the severity and number of threats these DUs are facing. Based on the assessed threats, over the next three generations it is expected that there will be a population level decline of 31-100% for DUs 2, 4, 5, 7, 16 and 17, and a 71% to 100% population level decline for DUs 8, 9, 10, 11, and 14. Alleviating the multiple and complex threats to these DUs will be difficult, especially as many of the threats are exacerbated by climate change. It will be critical to ensure that efforts are appropriately coordinated through effective governance to successfully mitigate the cumulative impacts of these diverse threats. Recovery targets, options for mitigation, forward population projections and allowable harm will be provided in the second half of the RPA (Elements 12-22). [ABSTRACT FROM AUTHOR]

The main objective of this study was to develop an innovative process to maximize the biotransformation of colloidal and soluble biodegradable matter (CSB) into particulate matter (XB) for energy recovery via methane production. Two configurations were studied: (1) high-rate moving bed bioreactor (HR-MBBR) and (2) inoculum-chemostat (IC) system consisting of a very HR-MBBR inoculating a continuous flow stirred-tank reactor. The effect of hydraulic retention time (HRT), specific organic loading rate (SOLR), and dissolved oxygen (DO) level were determined using real wastewater at pilot scale. Results showed that in the HR-MBBR process, a very high CSB biotransformation efficiency (90%) was obtained in a wide range of SOLRs (2.0 to 5.5 g C SB m-2 d-1) corresponding to an optimum HRT of 36 minutes. The IC process reached a maximum CSB biotransformation efficiency of 77%, at SOLRs ranging from 22 to 30 g CSB m-2 d-1 at an HRT of 3.7 hours. The DO concentration in the HR-MBBR influenced the CSB bio-transformation ratio, while the HRT and the SOLR were the dominant factors influencing this ratio in the IC process. Based on these results, the IC process could be an interesting alternative to high-rate systems towards obtaining energy positive/efficient from water resource recovery facilities. [ABSTRACT FROM AUTHOR]