Kootenay Lake kokanee (Oncorhynchus nerka) collapse into a predator pit

Kootenay Lake is a large, oligotrophic waterbody in southern British Columbia renowned for recreational fisheries for piscivorous rainbow trout (Oncorhynchus mykiss) and bull trout (Salvelinus confluentus). Long-term datasets showed a build-up of large-bodied (>2 kg) piscivore abundance followed by a collapse of the kokanee (Oncorhynchus nerka) prey population in 2013 and subsequent decline of large-bodied piscivores. An unprecedented post-collapse state formed in 2015-2018, characterized by low kokanee spawner abundance and biomass and high catch rates for small-bodied (<2 kg), slow growing piscivores. Bioenergetics model estimates of average historic (1961-2008) piscivore consumption was 29.3% of the average historic (1993-2008) kokanee prey supply (biomass and production), but increased to 78.7% in 2011, immediately preceding kokanee collapse. From 2015-2018, kokanee did not recover due to persistently poor juvenile survival; estimated piscivore consumption relative to prey supply remained high (73.0%), suggesting that kokanee were trapped in a predator pit. Although the ultimate and interacting causes of the initial predator build-up remain uncertain, overcoming current depensatory dynamics may be aided by kokanee stocking or increasing harvest on still-abundant, unsatiated piscivores.

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Hidradenoma papilliferum of the hymen: a case report

Journal of Medical Case Reports ◽

10.1186/s13256-021-02786-6 ◽

2021 ◽

Vol 15 (1) ◽

Author(s):

Ozer Birge ◽

Mehmet Sait Bakır ◽

Ceyda Karadag ◽

Zivar Eldarova ◽

Tayup Simsek

Keyword(s):

Benign Neoplasm ◽

Surgical Removal ◽

Apocrine Glands ◽

Sexually Transmitted ◽

Anogenital Region ◽

Hidradenoma Papilliferum ◽

Anogenital Area ◽

Slow Growing

Abstract Background Hidradenoma papilliferum is a rare benign neoplasm arising from apocrine glands. It occurs commonly on the anogenital region of middle-aged women. It usually presents as a slow growing, solitary asymptomatic, skin colored or red nodule less than 1 cm in diameter. Case presentation The case is a 38-year-old, white woman who presented with a painful nodule occurring within a month in the himenal region of the posterior vaginal introitus. The nodule was excisied and the histology revealed a hidradenoma papilliferum. The diagnosis and treatment of hidradenoma papilliferum is possible with surgical removal and histopathological evaluation of nodules. Conclusion When an adult woman presents with a noduler lesion in the anogenital area, sexually transmitted diseases and other benign and malignant vulvar lesions, as well as malignant transformation is very rare but,should be kept in mind; however because it has been reported and long-term clinical follow-up is suggested

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Vegetation and microbes interact to preserve carbon in many wooded peatlands

Communications Earth & Environment ◽

10.1038/s43247-021-00136-4 ◽

2021 ◽

Vol 2 (1) ◽

Author(s):

Hongjun Wang ◽

Jianqing Tian ◽

Huai Chen ◽

Mengchi Ho ◽

Rytas Vilgalys ◽

...

Keyword(s):

Microbial Composition ◽

Ecological Traits ◽

Low Latitude ◽

Carbon Decomposition ◽

Positive Effects ◽

Recalcitrant Carbon ◽

Effects Of Temperature ◽

Abiotic Controls ◽

Slow Growing

AbstractPeatlands have persisted as massive carbon sinks over millennia, even during past periods of climate change. The commonly accepted theory of abiotic controls (mainly anoxia and low temperature) over carbon decomposition cannot fully explain how vast low-latitude shrub/tree dominated (wooded) peatlands consistently accrete peat under warm and seasonally unsaturated conditions. Here we show, by comparing the composition and ecological traits of microbes between Sphagnum- and shrub-dominated peatlands, that slow-growing microbes decisively dominate the studied shrub-dominated peatlands, concomitant with plant-induced increases in highly recalcitrant carbon and phenolics. The slow-growing microbes metabolize organic matter thirty times slower than the fast-growing microbes that dominate our Sphagnum-dominated site. We suggest that the high-phenolic shrub/tree induced shifts in microbial composition may compensate for positive effects of temperature and/or drought on metabolism over time in peatlands. This biotic self-sustaining process that modulates abiotic controls on carbon cycling may improve projections of long-term, climate-carbon feedbacks in peatlands.

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Myopericytoma in the Antitragus of the Auricle: A Rare Tumor

Ear Nose & Throat Journal ◽

10.1177/0145561320984576 ◽

2020 ◽

pp. 014556132098457

Author(s):

Tae Seong Eo ◽

Jeong Hae Kie ◽

Hyun Seung Choi ◽

Junhui Jeong

Keyword(s):

Large Firm ◽

Rare Tumor ◽

Long Term Follow Up ◽

Slow Growing ◽

Rule Out

A myopericytoma in the auricle is rare. If an auricle contains a large, firm, red-brown mass, excision should be considered because the mass may be a myopericytoma. After excision, histopathological and immunohistochemical diagnoses are essential to rule out malignancy. Long-term follow-up is required because the tumor is slow-growing.

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Giant Parotid Pleomorphic Adenoma with Atypical Histological Presentation and Long-Term Recurrence-Free Follow-Up after Surgery: A Case Report and Review of the Literature

Case Reports in Dentistry ◽

10.1155/2020/8828775 ◽

2020 ◽

Vol 2020 ◽

pp. 1-18

Author(s):

Mohammed AlKindi ◽

Sundar Ramalingam ◽

Lujain Abdulmajeed Hakeem ◽

Manal A. AlSheddi

Keyword(s):

Pleomorphic Adenoma ◽

Surgical Management ◽

Early Stage ◽

English Literature ◽

Benign Tumors ◽

Adjuvant Radiation ◽

Extracapsular Dissection ◽

Slow Growing

Salivary gland tumors (SGT) comprise 3% of all head and neck tumors, are mostly benign, and arise frequently in the parotid gland. Pleomorphic adenoma (PA) is the commonest SGT, representing 60-70% of all benign parotid tumors. Clinically, parotid PA presents as irregular, lobulated, asymptomatic, slow-growing preauricular mass, involving both superficial and deep lobes, and could grow to gigantic proportions. Histologically, PA has epithelial and mesenchymal elements in chondromyxoid matrix and is managed surgically. Based on a review of 43 cases reported in English literature since 1995, giant parotid PA is reported as large as 35 cm (diameter) and 7.3 kg (resected weight). Although rare, 10 cases of malignant transformation were reported in the review. Surgical management included extracapsular dissection (ECD), superficial parotidectomy, and total parotidectomy for benign tumors, and adjuvant radiation or chemotherapy for malignant tumors. We further present the case of a 36-year-old healthy male with slow-growing and asymptomatic giant parotid PA, of 4-year duration. The patient presented with firm, lobulated preauricular swelling, provisionally diagnosed as PA based on radiographic and cytological findings. The tumor was resected through ECD, and the patient had uneventful postoperative recovery and a 7-year recurrence-free follow-up period. Histological examination revealed epimyoepithelial proliferation punctuated by chondromyxoid areas, with extensive squamous metaplasia and keratin cysts. To the best of knowledge from indexed literature, giant parotid PA is rarely reported in Saudi Arabia. In addition to its rarity, this case is reported for its benign nature despite atypical histological presentation, successful surgical management without complications, and long-term recurrence-free follow-up. Based on this report, clinicians must be aware of atypical histological presentations associated with PA and plan suitable surgical management and follow-up to avoid morbidity. Nevertheless, attempts must be made to diagnose and manage these lesions at an early stage and before they reach gigantic proportions.

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Size Selectivity of Diamond and Square Mesh Codends in Pelagic Herring Trawls: Only Small Herring Will Notice the Difference

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f92-234 ◽

1992 ◽

Vol 49 (10) ◽

pp. 2104-2117 ◽

Cited By ~ 38

Author(s):

Petri Suuronen ◽

Russell B. Millar

Keyword(s):

Relative Size ◽

Mesh Size ◽

The Other ◽

Size Selectivity ◽

The Difference ◽

Catch Rates ◽

Two Sides ◽

High Catch

A twin codend trawl was fished in the northern Baltic to study the size selectivity of square mesh and diamond mesh codends of 36-mm nominal mesh size. For each codend, 15 hauls were completed with a small mesh (20 mm) codend deployed on the other side of the trawl. The relative size of the catches in the two sides of the trawl varied considerably from haul to haul (the separator section was not operating properly) and selection curves were estimated from each individual haul using a method that incorporated the differences in catching efficiency of the two sides. The length of 50% retention decreased with increased catch for both the diamond and square mesh codends, although in neither case was this relationship statistically significant. Selection curves fitted to the combined haul data were asymmetric. The square mesh codend retained significantly less small herring than the diamond mesh codend, and for larger herring the two codends had similar selectivity. In both codends, most escapes occurred at the front of the catch bulge, from the upper side of the codend. At high catch rates, mesh blockage was observed for several metres ahead of the catch bulge during the later part of the tow.

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Feeding behaviour of fast-and slow-growing strains of rainbow trout, Oncorhynchus mykiss (Walbaum), during first feeding

Aquaculture Research ◽

10.1046/j.1365-2109.2001.00645.x ◽

2001 ◽

Vol 32 (10) ◽

pp. 861-861

Author(s):

L M P Valente ◽

P Saglio ◽

L M Cunha ◽

B Fauconneau

Keyword(s):

Rainbow Trout ◽

Oncorhynchus Mykiss ◽

Feeding Behaviour ◽

Rainbow Trout Oncorhynchus Mykiss ◽

First Feeding ◽

Slow Growing

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Postsmolt Atlantic Salmon (Salmo salar) in the Labrador Sea

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f91-001 ◽

1991 ◽

Vol 48 (1) ◽

pp. 2-6 ◽

Cited By ~ 40

Author(s):

D. G. Reddin ◽

P. B. Short

Keyword(s):

Atlantic Salmon ◽

Salmo Salar ◽

Age Distribution ◽

Labrador Sea ◽

Scale Reading ◽

Gill Nets ◽

Atlantic Salmon Salmo Salar ◽

Catch Rates ◽

Abundance And Distribution ◽

High Catch

In order to learn more about the existence, abundance, and distribution of postsmolt Atlantic salmon (Salmo salar) in the Labrador Sea, exploratory fishing was done with surface-set gill nets in early autumn of 1987 and 1988. In total, there were 468 salmon of various sea ages captured, of which 207 were postsmolts. The high catch rates compared with catch rates from Greenland suggest that the population of postsmolts in the Labrador Sea may be large. Postsmolts from rivers in Maine to Labrador were caught in the Labrador Sea, as indicated by Carlin tags and river age distribution from scale reading. The highest catch rates of postsmolts occurred in the Labrador Sea between 56° and 58°N latitude.

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