scholarly journals Life histories of three Serrulinini species (Stylommatophora: Clausiliidae) from Georgia kept under laboratory conditions

2021 ◽  
Vol 29 (3) ◽  
Author(s):  
Anna Sulikowska-Drozd ◽  
Levan Mumladze

The Serrulinini, a small relict group of clausiliids occurring in coastal regions of the Black and Caspian Seas and the Caucasus, are currently classified within the Phaedusinae, however paraphyletic origin of the Serrulinini is also widely debated with Pontophaedusa funiculum (Mousson) being most phylogenetically distinct from other taxa. As life history data may have taxonomical value, we conducted long-term observations in laboratory culture to assess reproductive modes, fecundity and growth pattern of three serruline species. Caspiophaedusa perlucens (O. Boettger) and Pravispira semilamellata (Mousson) produced partly calcified eggs with regular, spiral arrangement of crystals; their juveniles hatched after 17–18 days; the generation time was long and significantly exceeded one year. P. funiculum laid heavily calcified, elongated eggs. The incubation time in P. funiculum varied depending on the humidity, with a tendency towards short embryo-retention. The generation time in P. funiculum was one year. In all the studied species, egg calcification differed from the pattern common for other oviparous Phaedusinae which produce partly calcified eggs with homogeneous distribution of crystals. The calcite crystal distribution in the egg membranes reported here for the Serrulinini suggests some potential of these characters in phylogenetic context.

2021 ◽  
Author(s):  
Lars Witting

I use 56,214 life history data to estimate equilibrium life history models for birds and mammals with body mass estimates. Missing parameters were estimated by allometric correlations at the lowest taxonomic level (genus, family, order, class) with data. The estimation is optimised to predict the existing data, with precision estimated separately for the different taxonomic levels of the estimator. This provides complete life history models for 9,488 species of birds, and 4,865 species of mammals. Each model includes estimates of metabolism, net assimilated energy, individual growth, mortality, fecundity, age of reproductive maturity, generation time, life span, home range, population density, biomass, population consumption, and a relative measure of intra-specific interactive competition, providing 387,531 parameter estimates in total.


2021 ◽  
Vol 4 (Supplement_1) ◽  
pp. 234-236
Author(s):  
P Willems ◽  
J Hercun ◽  
C Vincent ◽  
F Alvarez

Abstract Background The natural history of primary sclerosing cholangitis (PSC) in children seems to differ from PSC in adults. However, studies on this matter have been limited by short follow-up periods and inconsistent classification of patients with autoimmune cholangitis (AIC) (or overlap syndrome). Consequently, it remains unclear if long-term outcomes are affected by the clinical phenotype. Aims The aims of this is study are to describe the long-term evolution of PSC and AIC in a pediatric cohort with extension of follow-up into adulthood and to evaluate the influence of phenotype on clinical outcomes. Methods This is a retrospective study of patients with AIC or PSC followed at CHU-Sainte-Justine, a pediatric referral center in Montreal. All charts between January 1998 and December 2019 were reviewed. Patients were classified as either AIC (duct disease on cholangiography with histological features of autoimmune hepatitis) or PSC (large or small duct disease on cholangiography and/or histology). Extension of follow-up after the age of 18 was done for patients followed at the Centre hospitalier de l’Université de Montréal. Clinical features at diagnosis, response to treatment at one year and liver-related outcomes were compared. Results 40 patients (27 PSC and 13 AIC) were followed for a median time of 71 months (range 2 to 347), with 52.5% followed into adulthood. 70% (28/40) had associated inflammatory bowel disease (IBD) (78% PSC vs 54% AIC; p=0.15). A similar proportion of patients had biopsy-proven significant fibrosis at diagnosis (45% PSC vs 67% AIC; p=0.23). Baseline liver tests were similar in both groups. At diagnosis, all patients were treated with ursodeoxycholic acid. Significantly more patients with AIC (77% AIC vs 30 % PSC; p=0.005) were initially treated with immunosuppressive drugs, without a significant difference in the use of Anti-TNF agents (0% AIC vs 15% PSC; p= 0.12). At one year, 55% (15/27) of patients in the PSC group had normal liver tests versus only 15% (2/13) in the AIC group (p=0.02). During follow-up, more liver-related events (cholangitis, liver transplant and cirrhosis) were reported in the AIC group (HR=3.7 (95% CI: 1.4–10), p=0.01). Abnormal liver tests at one year were a strong predictor of liver-related events during follow-up (HR=8.9(95% CI: 1.2–67.4), p=0.03), while having IBD was not (HR=0.48 (95% CI: 0.15–1.5), p=0.22). 5 patients required liver transplantation with no difference between both groups (8% CAI vs 15% CSP; p=0.53). Conclusions Pediatric patients with AIC and PSC show, at onset, similar stage of liver disease with comparable clinical and biochemical characteristics. However, patients with AIC receive more often immunosuppressive therapy and treatment response is less frequent. AIC is associated with more liver-related events and abnormal liver tests at one year are predictor of bad outcomes. Funding Agencies None


2021 ◽  
Vol 7 ◽  
pp. 237802312110247
Author(s):  
Alexandrea J. Ravenelle ◽  
Abigail Newell ◽  
Ken Cai Kowalski

The authors explore media distrust among a sample of precarious and gig workers interviewed during the COVID-19 pandemic. Although these left-leaning respondents initially increased their media consumption at the outset of the pandemic, they soon complained of media sensationalism and repurposed a readily available cultural tool: claims of “fake news.” As a result, these unsettled times have resulted in a “diffusion of distrust,” in which an elite conservative discourse of skepticism toward the media has also become a popular form of compensatory control among self-identified liberals. Perceiving “fake news” and media sensationalism as “not good” for their mental health, respondents also reported experiencing media burnout and withdrawing from media consumption. As the pandemic passes its one-year anniversary, this research has implications for long-term media coverage on COVID-19 and ongoing media trust and consumption.


Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Jessie M. Dodge ◽  
Eva K. Strand ◽  
Andrew T. Hudak ◽  
Benjamin C. Bright ◽  
Darcy H. Hammond ◽  
...  

Abstract Background Fuel treatments are widely used to alter fuels in forested ecosystems to mitigate wildfire behavior and effects. However, few studies have examined long-term ecological effects of interacting fuel treatments (commercial harvests, pre-commercial thinnings, pile and burning, and prescribed fire) and wildfire. Using annually fitted Landsat satellite-derived Normalized Burn Ratio (NBR) curves and paired pre-fire treated and untreated field sites, we tested changes in the differenced NBR (dNBR) and years since treatment as predictors of biophysical attributes one and nine years after the 2007 Egley Fire Complex in Oregon, USA. We also assessed short- and long-term fuel treatment impacts on field-measured attributes one and nine years post fire. Results One-year post-fire burn severity (dNBR) was lower in treated than in untreated sites across the Egley Fire Complex. Annual NBR trends showed that treated sites nearly recovered to pre-fire values four years post fire, while untreated sites had a slower recovery rate. Time since treatment and dNBR significantly predicted tree canopy and understory green vegetation cover in 2008, suggesting that tree canopy and understory vegetation cover increased in areas that were treated recently pre fire. Live tree density was more affected by severity than by pre-fire treatment in either year, as was dead tree density one year post fire. In 2008, neither treatment nor severity affected percent cover of functional groups (shrub, graminoid, forb, invasive, and moss–lichen–fungi); however, by 2016, shrub, graminoid, forb, and invasive cover were higher in high-severity burn sites than in low-severity burn sites. Total fuel loads nine years post fire were higher in untreated, high-severity burn sites than any other sites. Tree canopy cover and density of trees, saplings, and seedlings were lower nine years post fire than one year post fire across treatments and severity, whereas live and dead tree basal area, understory surface cover, and fuel loads increased. Conclusions Pre-fire fuel treatments effectively lowered the occurrence of high-severity wildfire, likely due to successful pre-fire tree and sapling density and surface fuels reduction. This study also quantified the changes in vegetation and fuels from one to nine years post fire. We suggest that low-severity wildfire can meet prescribed fire management objectives of lowering surface fuel accumulations while not increasing overstory tree mortality.


Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3390
Author(s):  
Mats Enlund

Retrospective studies indicate that cancer survival may be affected by the anaesthetic technique. Propofol seems to be a better choice than volatile anaesthetics, such as sevoflurane. The first two retrospective studies suggested better long-term survival with propofol, but not for breast cancer. Subsequent retrospective studies from Asia indicated the same. When data from seven Swedish hospitals were analysed, including 6305 breast cancer patients, different analyses gave different results, from a non-significant difference in survival to a remarkably large difference in favour of propofol, an illustration of the innate weakness in the retrospective design. The largest randomised clinical trial, registered on clinicaltrial.gov, with survival as an outcome is the Cancer and Anesthesia study. Patients are here randomised to propofol or sevoflurane. The inclusion of patients with breast cancer was completed in autumn 2017. Delayed by the pandemic, one-year survival data for the cohort were presented in November 2020. Due to the extremely good short-term survival for breast cancer, one-year survival is of less interest for this disease. As the inclusions took almost five years, there was also a trend to observe. Unsurprisingly, no difference was found in one-year survival between the two groups, and the trend indicated no difference either.


Oryx ◽  
2021 ◽  
pp. 1-9
Author(s):  
Harry Olgun ◽  
Mzee Khamis Mohammed ◽  
Abbas Juma Mzee ◽  
M. E. Landry Green ◽  
Tim R. B. Davenport ◽  
...  

Abstract Roads affect wildlife in a variety of negative ways. Road ecology studies have mostly concentrated on areas in the northern hemisphere despite the potentially greater impact of roads on biodiversity in tropical habitats. Here, we examine 4 years (January 2016–December 2019) of opportunistic observations of mammalian roadkill along a road intersecting Jozani-Chwaka Bay National Park, Unguja, Zanzibar. In particular, we assess the impact of collisions on the population of an endemic primate, the Endangered Zanzibar red colobus Piliocolobus kirkii. Primates accounted for the majority of roadkill in this dataset. Monthly rainfall was not associated with roadkill frequency for mammals generally, nor for the Zanzibar red colobus. No single age–sex class of colobus was found dead more often than expected given their occurrence in the local population. The overall effect of roadkill on colobus populations in habitats fragmented by roads is unknown given the lack of accurate, long-term life history data for this species. Our findings suggest that mortality from collisions with vehicles in some groups of colobus is within the range of mortality rates other primates experience under natural predation. Unlike natural predators, however, vehicles do not kill selectively, so their impact on populations may differ. Although a comparison with historical accounts suggests that the installation of speedbumps along the road near the Park's entrance has led to a significant decrease in colobus roadkill, further actions to mitigate the impact of the road could bring substantial conservation benefits.


Vascular ◽  
2020 ◽  
pp. 170853812098112
Author(s):  
Cassra N Arbabi ◽  
Navyash Gupta ◽  
Ali Azizzadeh

Objectives Thoracic endovascular aortic repair (TEVAR) is the standard of care for descending thoracic aortic aneurysms (DTAA), and newer generation stent grafts have significant design improvements compared to earlier generation devices. Methods We report the first commercial use of the Medtronic Valiant Navion stent graft for treatment of an 85-year-old woman with a 5.8 cm DTAA and a highly tortuous thoracic aorta. Results A percutaneous TEVAR was performed using a two-piece combination of the Valiant Navion FreeFlo and CoveredSeal stent graft configurations for zones 2–5 coverage. The devices were successfully delievered through highly tortuous anatomy and deployed, excluding the entire length of the aneurysm with precise landing, excellent apposition and no evidence of endoleak. The patient tolerated the procedure well and has had no stent graft-related complications through one-year follow-up. Conclusions Design enhancements such as a lower profile delivery system, better conformability, and a shorter tapered tip are some of the improvements to this third-generation TEVAR device. Coupled with the multiple configuration options available, this gives physicians a better tool to treat thoracic aortic pathologies in patients with challenging anatomy. The early results are encouraging, and evaluation of long-term outcomes will continue.


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