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We collected fishes and habitat data at 138 streams to evaluate the effects of introduced brown trout (Salmo trutta) and habitat conditions on occurrence, detection, abundance, and size structure of sculpin (Cottus spp.), longnose dace (Rhinichthys cataractae), and southern redbelly dace (Chrosomus erythrogaster) in the Driftless Area, USA. Sculpin detection decreased with increasing stream velocity, whereas southern redbelly dace detection increased with stream depth. Sculpin occupancy declined with increasing stream temperature and velocity and increased with increasing forested land, boulder substrate, and brown trout length and abundance. Longnose and southern redbelly dace occupancy and abundance declined with increasing brown trout abundance and occupancy increased with stream temperature. Longnose dace occupancy also increased with increasing stream temperature and cobble substrate and declined with increasing elevation. Native fish size structure was unrelated to brown trout presence. Our results suggest that effects of brown trout are not ubiquitous across native fishes and depend on abiotic conditions and species-specific habitat requirements, highlighting the need to consider both biotic and abiotic conditions when balancing native species conservation with introduced sportfish management. Key words: brown trout, occupancy, conservation, species of greatest conservation need, biotic interactions, habitat associations, 1. Introduction The establishment and expansion of introduced non-native sport fishes threaten aquatic ecosystems globally. Brown trout (Salmo trutta) is one of the most introduced freshwater fishes (Welcomme 1992; Rahel [...]

Targeted therapies such as venetoclax (VEN) (Bcl-2 inhibitor) have revolutionized the treatment of chronic lymphocytic leukemia (CLL). We previously reported that persister CLL cells in treated patients overexpress multiple antiapoptotic proteins and display resistance to proapoptotic agents. Here, we demonstrated that multidrug-resistant CLL cells in vivo exhibited apoptosis restriction at a pre-mitochondrial level due to insufficient activation of the Bax and Bak (Bax/Bak) proteins. Co-immunoprecipitation analyses with selective BH domain antagonists revealed that the pleiotropic proapoptotic protein (Bim) was prevented from activating Bax/Bak by 'switching' interactions to other upregulated antiapoptotic proteins (Mcl-1, Bcl-xL, Bcl-2). Hence, treatments that bypass Bax/Bak restriction are required to deplete these resistant cells in patients. Protein phosphatase 2A (PP2A) contributes to oncogenesis and treatment resistance. We observed that small-molecule activator of PP2A (SMAP) induced cytotoxicity in multiple cancer cell lines and CLL samples, including multidrug-resistant leukemia and lymphoma cells. The SMAP (DT-061) activated apoptosis in multidrug-resistant CLL cells through induction of mitochondrial permeability transition pores, independent of Bax/Bak. DT-061 inhibited the growth of wild-type and Bax/Bak doubleknockout, multidrug-resistant CLL cells in a xenograft mouse model. Collectively, we discovered multidrug-resistant CLL cells in patients and validated a pharmacologically tractable pathway to deplete this reservoir., Introduction The introduction of proapoptotic pharmacological agents such as the antiapoptotic protein Bcl-2 inhibitor VEN has revolutionized the treatment of chronic lymphocytic leukemia (CLL) and mantle cell lymphoma (MCL). Although [...]

Popularity of bass (Micropterus spp.) catch and release and tournament angling during the past decade has resulted in increased potential for these activities to induce population level effects. Understanding capture rates and mortality sources relative to total population mortality is essential to focus of management. We conducted monthly electrofishing, solicited non-tournament angler tag returns, and censused largemouth bass (Micropterus salmoides) tournaments at Brushy Creek Lake, Iowa, USA, from April 2015 to June 2018. We used a multistate mark-recapture model to evaluate the effects of air temperature, water temperature, tournament bass per angler, and tournament initial mortality on non-tournament and tournament angler capture probability and natural, non-tournament angling, and initial and delayed tournament mortality. Average total annual mortality was 0.66 with natural mortality representing the largest mortality source (0.57) followed by delayed tournament mortality (0.06), non-tournament angling mortality (0.02), and initial tournament mortality (0.006). Our results reveal both non-tournament and tournament angling mortality are low compared to natural mortality in some lakes. Therefore, cumulative angling mortality likely has minimal population level effects on some bass populations. La popularite de la peche avec remise a l'eau et des tournois de peche a l'achigan (Micropterus spp.) au cours de la derniere decennie s'est traduite par un potentiel accru d'effets de ces activites a l'echelle de la population. La comprehension des taux de capture et des sources de mortalite par rapport a la mortalite totale de la population est un aspect central de la gestion. Nous avons realise des peches electroniques mensuelles, sollicite les etiquettes prelevees par des pecheurs hors tournois et effectue des recensements dans des tournois de peche a l'achigan a grande bouche (Micropterus salmoides) au lac Brushy Creek (Iowa, Etats-Unis) d'avril 2015 a juin 2018. Nous avons utilise un modele multi-etats de marquage- recapture pour evaluer les effets de la temperature de l'air, de la temperature de l'eau et du nombre d'achigans peches par pecheur et de la mortalite initiale dans le cadre de tournois sur la probabilite de capture par pecheur dans le cadre de tournois et hors tournois et sur la mortalite naturelle hors tournois et les mortalites initiale et differee associees aux tournois. Le taux de mortalite annuel total moyen etait de 0,66, la mortalite annuelle en representant la plus grande source (0,57), suivie de la mortalite differee des tournois (0,06), de la mortalite par peche hors tournois (0,02) et de la mortalite initiale des tournois (0,006). Nos resultats revelent que les taux de mortalite par peche tant dans le cadre de tournois que hors tournois sont faibles comparativement a la mortalite naturelle dans certains lacs. La mortalite cumulative par peche a donc probablement des effets limites a l'echelle de la population sur certaines populations d'achigans. [Traduit par la Redaction], Introduction Largemouth bass (Micropterus salmoides) represent an example of shifts in angler behaviors and motivations. Historically, over-harvest of black bass (Micropterus spp.) was common (Holbrook 1975; Redmond 1986; Long et [...]

Objective: Walleye Sander vitreus are important sport fish that are commonly stocked to supplement populations. Increases in Smallmouth Bass Micropterus dolomieu abundance have prompted concerns regarding potential predation by these and other piscivores on stocked Walleye. Our objectives were to assess the timing and duration of predation on stocked Walleye, the frequency of occurrence and percent composition of Walleye in predator diets, and the percentage of stocked Walleye consumed. Methods: We collected Smallmouth Bass, adult Walleye, Largemouth Bass M. nigricans, and Northern Pike Esox lucius diets in May (prestocking) and June–September (poststocking) 2019 and 2021 from three bays in Lake Oahe, South Dakota. We stocked two bays with Walleye (30–32 mm; 255–1649 Walleye/ha), whereas one bay was unstocked and served as a reference. We estimated Smallmouth Bass population abundance using Schnabel capture–recapture models, and we used bioenergetics to estimate the percentage of stocked age‐0 Walleye consumed. Result: We found age‐0 Walleye in up to 11.4% of Smallmouth Bass diets and 14.6% of adult Walleye diets during the poststocking period. A single Largemouth Bass consumed one Walleye at 3 days poststocking (DPS), whereas we did not identify Walleye in Northern Pike diets. Daily mean percent composition by weight (±95% confidence interval) of age‐0 Walleye in diets peaked at 43.2 ± 35.1% at 3 DPS for Smallmouth Bass and 49.8 ± 97.7% at 14 DPS for adult Walleye. Following the peaks, age‐0 Walleye percent composition by weight rapidly declined and was generally 0% after 25 DPS. Smallmouth Bass abundance was 0.4–5.6 fish/ha, whereas recaptures of other predator species were insufficient for reliable population estimates. We estimated that Smallmouth Bass consumed 29,930 age‐0 Walleye in 2019 and 12,535 age‐0 Walleye in 2021 (up to 14.7 ± 4.7% of stocked fish), potentially representing an important source of stocking mortality. Conclusion: Our research provides insights into the effects of poststocking predation on age‐0 Walleye by Smallmouth Bass and, to a lesser extent, Walleye, Largemouth Bass, and Northern Pike. Managers should consider predation on stocked fingerling Walleye from resident predators and should contemplate alternative stocking locations or timing to reduce potential predation. Impact statementPredation may influence poststocking survival. We found that Smallmouth Bass were the most common predators of stocked age‐0 Walleye, predation generally occurred within 14 days poststocking, and up to 14.7% of stocked fish were consumed. Our results can guide management decisions for improving Walleye stocking success. [ABSTRACT FROM AUTHOR]

The Melanoma Research Foundation (MRF) has charted a comprehensive assessment of the current state of melanoma research and care. Intensive discussions among members of the MRF Scientific Advisory Council and Breakthrough Consortium, a group that included clinicians and scientists, focused on four thematic areas - diagnosis/early detection, prevention, tumor cell dormancy (including metastasis), and therapy (response and resistance). These discussions extended over the course of 2015 and culminated at the Society of Melanoma Research 2015 International Congress in November. Each of the four groups has outlined their thoughts as per the current status, challenges, and opportunities in the four respective areas. The current state and immediate and long-term needs of the melanoma field, from basic research to clinical management, are presented in the following report.

Fish recruitment is complex, regulated by environmental factors that induce high mortality early in life. Additionally, age-0 fish can be difficult to sample, making recruitment difficult to detect. We used a robust design occupancy model to evaluate the effects of biotic (age-0 and adult common carp (Cyprinus carpio), bluegill (Lepomis macrochirus), walleye (Sander vitreus), and northern pike (Esox lucius) relative abundance, prey availability, age-0 carp length) and abiotic (water level, temperature) factors on age-0 carp occupancy, detection, and extinction in 13 lakes in South Dakota, USA, for July-April 2008-2010. Age-0 carp occupancy decreased with increasing adult carp abundance and increased with increasing water levels. Age-0 carp detection probability was high during summer (>0.75) but decreased in fall and spring (0.34). Most lakes were occupied in July but overwinter extinction probability was high (59%), resulting in 51% occupancy probability by April. Other environmental factors were not supported, suggesting they had little effect on reproduction and survival. Our results indicate reproduction was universally successful but difficult to detect and that overwinter mortality often resulted in recruitment failure. Le recrutement de poissons est un phenomene complexe module par des facteurs environnementaux qui induisent une forte mortalite au debut du cycle de vie. L'echantillonnage de poissons d'age 0 peut en outre s'averer difficile, ce qui rend le recrutement difficile a detecter. Nous avons utilise un modele d'occupation a conception robuste pour evaluer les effets de facteurs biotiques (abondance relative de carpes communes (Cyprinus carpio), crapets arlequins (Lepomis macrochirus), dores jaunes (Sander vitreus) et grands brochets (Esox lucius) d'age 0 et adultes, disponibilite de proies, longueur des carpes d'age 0) et abiotiques (niveau d'eau, temperature) sur l'occupation, la detection et la disparition de carpes d'age 0 dans 13 lacs du Dakota du Sud (Etats-Unis), de juillet a avril 2008-2010. L'occupation de carpes d'age 0 diminuait avec l'augmentation de l'abondance de carpes adultes et augmentait a mesure qu'augmentaient les niveaux d'eau. La probabilite de detection de carpes d'age 0 etait forte durant l'ete (>0,75), mais diminuait a l'automne et au printemps (0,34). La plupart des lacs etaient occupes en juillet, mais la probabilite de disparition hivernale etait elevee (59 %), se traduisant par une probabilite d'occupation en avril de 51 %. Les modeles n'appuient pas d'autres facteurs environnementaux, donnant a penser que ces facteurs avaient peu d'effet sur la reproduction et la survie. Nos resultats indiquent un succes de reproduction generalise bien que difficile a detecter et que la mortalite hivernale entrainait souvent un echec du recrutement. [Traduit par la Redaction], Introduction Elucidating complex, interrelated biotic and abiotic factors that dynamically interact to regulate fish recruitment has challenged and perplexed fisheries scientists for decades. In freshwater systems, predation is often cited [...]

Catch per unit effort (CPUE) is used as an index of fish abundance under the premise that changes in CPUE result from changes in true density. However, catchability may also vary based on environmental conditions that affect observed CPUE. We developed a hierarchical model for estimating common carp (Cyprinus carpio) and bigmouth buffalo (Ictiobus cyprinellus) relative abundance with electrofishing survey data from six shallow lakes in northwest Iowa, USA, between 2018 and 2020. Common carp catchability was negatively associated with lake perimeter but unrelated to lake surface area, water depth, Secchi depth, temperature, and month of sampling. Bigmouth buffalo catchability was negatively associated with Secchi depth and water temperature and unrelated to other environmental variables. Hierarchical model posterior distributions of bigmouth buffalo density were less precise than Schnabel estimates, whereas common carp posterior distribution abundance estimates were more precise than Schnabel estimates. Our results indicate that hierarchical models can be a viable substitute for labor-intensive capture–mark–recapture methods to estimate unknown latent variables like relative abundance, and could be applied to other species, sampling gears, and management frameworks. [ABSTRACT FROM AUTHOR]