scholarly journals The reintroduction of boreal caribou as a conservation strategy: A long-term assessment at the southern range limit

Rangifer ◽  
2012 ◽  
Vol 32 (2) ◽  
pp. 127 ◽  
Author(s):  
Martin-Hugues St-Laurent ◽  
Christian Dussault

Boreal caribou were extirpated from the Charlevoix region (Québec) in the 1920s because of hunting and poaching. In 1965, the Québec government initiated a caribou reintroduction program in Charlevoix. During the winters of 1966 and 1967, a total of 48 boreal caribou were captured, translocated by plane, and released within enclosures; only their offspring (82 individuals) were released in the wild. Between 1967 and 1980, a wolf control program was applied to support caribou population growth. The caribou population, however, remained relatively stable at 45–55 individuals during this period. During the 1980s, the population grew slowly at a rate of approximately 5% each year to reach a peak of 126 individuals in 1992. At that time, Bergerud & Mercer (1989) reported that the Charlevoix experiment was the only successful attempt at caribou reintroduction in the presence of predators (in North America). Afterwards, the population declined and since then it has been relatively stable at about 80 individuals. Here we reviewed the literature regarding the ecology and population dynamics of the Charlevoix caribou herd since its reintroduction, in an attempt to critically assess the value of reintroduction as a conservation tool for this species. Indeed, the Charlevoix caribou herd is now considered at very high risk of extinction mostly because of its small size, its isolation from other caribou populations, and low recruitment. The Charlevoix region has been heavily impacted by forestry activities since the early 1980s. Recent studies have indicated that these habitat modifications may have benefited populations of wolves and black bears—two predators of caribou—and that caribou range fidelity may have exposed caribou to higher predation risk via maladaptive habitat selection. As females are ageing, and females and calves suffer high predation pressure from wolves and bears respectively, we suggest that the future of this reintroduced herd is in question and that they are facing a high probability of extinction in the near future if further action is not taken.

2017 ◽  
Vol 7 (2) ◽  
pp. 207-230 ◽  
Author(s):  
Mustafa Murat Yucesahin ◽  
Ibrahim Sirkeci

Syrian crisis resulted in at least 6.1 million externally displaced people 983,876 of whom are in Europe while the rest are in neighbouring countries in the region. Turkey, due to its geographical proximity and substantial land borders with the country, has been the most popular destination for those fleeing Syria since April 2011. Especially after 2012, a sharp increase in the number of Syrian refugees arriving in Turkey was witnessed. This has triggered an exponential growth in academic and public interest in Syrian population. Numerous reports mostly based on non-representative sample surveys have been disseminated whilst authoritative robust analyses remained absent. This study aims to fill this gap by offering a comprehensive demographic analysis of the Syrian population. We focus on the demographic differences (from 1950s to 2015) and demographic trends (from 2015 to 2100) in medium to long term, based on data from World Population Prospects (WPP). We offer a comparative picture to underline potential changes and convergences between populations in Syria, Turkey, Germany, and the United Kingdom. We frame our discussion here with reference to the demographic transition theory to help understanding the implications for movers and non-movers in receiving countries in the near future.


Author(s):  
Kazuho Isono ◽  
Ryo Tsukimoto ◽  
Satoshi Iuchi ◽  
Akihisa Shinozawa ◽  
Izumi Yotsui ◽  
...  

Abstract Plants are often exposed not only to short-term (S-) heat stress but also to diurnal long-term (L-) heat stress over several consecutive days. To reveal the mechanisms underlying L-heat stress tolerance, we here used a forward genetic screening for sensitive to long-term heat (sloh) mutants and isolated sloh4. The mutant was hypersensitive to L- but not S-heat stress. The causal gene of sloh4 was identical to MIP3 encoding a member of the MAIGO2 (MAG2) tethering complex, which is composed of the MAG2, MIP1, MIP2, and MIP3 subunits and is localized at the endoplasmic reticulum (ER) membrane. Although sloh4/mip3 was hypersensitive to L-heat stress, the sensitivity of the mag2-3 and mip1–1 mutants was similar to that of the wild type. Under L-heat stress, the ER stress and the following unfolded protein response (UPR) were more pronounced in sloh4 than in the wild type. Transcript levels of bZIP60-regulated UPR genes were strongly increased in sloh4 under L-heat stress. Two processes known to be mediated by INOSITOL REQUIRING ENZYME1 (IRE1)—accumulation of the spliced bZIP60 transcript and a decrease in the transcript levels of PR4 and PRX34, encoding secretory proteins—were observed in sloh4 in response to L-heat stress. These findings suggest that misfolded proteins generated in sloh4 under L-heat stress may be recognized by IRE1 but not bZIP28, resulting in initiation of the UPR via activated bZIP60. Therefore, it would be possible that only MIP3 in MAG2 complex has an additional function in L-heat tolerance, which is not related to the ER–Golgi vesicle tethering.


2019 ◽  
Vol 5 (1) ◽  
Author(s):  
Masaki Nio ◽  
Motoshi Wada ◽  
Hideyuki Sasaki ◽  
Hiromu Tanaka ◽  
Masatoshi Hashimoto ◽  
...  

Abstract Background Although cancer occurrence following surgery for biliary atresia has gradually increased, the development of cholangiocarcinoma in a native liver survivor of biliary atresia is extremely rare. Case presentation A 3-month-old female patient with the correctable type of biliary atresia underwent a cystoduodenostomy. At 16 years of age, she underwent multiple surgeries including lysis of intestinal adhesions, ileostomy, and gastrojejunostomy at another hospital. At 54 years of age, she underwent lithotomy at the porta hepatis, resection of the residual cystic bile duct with gallbladder, and hepaticojejunostomy in Roux-en-Y fashion. As she approached the age of 63, her computed tomography scan showed no liver tumors. In the following year, she developed cholangiocarcinoma at the porta hepatis and underwent chemotherapy. However, the cancer progressed, and she died before she reached the age of 64 years. Conclusions Cholangiocarcinoma is extremely rare in patients with biliary atresia. However, physicians should follow up patients with biliary atresia as closely as possible, as malignant tumors secondary to biliary atresia may increase in number in the near future because of the growing number of long-term survivors with biliary atresia.


1993 ◽  
Vol 5 (1) ◽  
pp. 29-38 ◽  
Author(s):  
FA Van Assche

Major progress has been made in the knowledge and management of diabetes and pregnancy. However diabetes in pregnancy remains an important medical complication, with implications for mother and child in both the short and the long term. There are still controversies concerning the diagnostic criteria of gestational diabetes and concerning the best strategry for the treatment of this disorder. There is even less agreement about whether gestational diabetes is a pathological condition. The perinatal mortality in gestational diabetes has recently become as low as that in the general population. This has led to the conclusion that gestational diabetes is no more than a variant of metabolic adaptation during pregnancy. However, fetal hyperinsulinism is present in gestational diabetes, resulting in macrosomia, neonatal complications and most probably long term consequences. Improvements in the care of the preexisting insulin-dependent pregnant diabetic have been achieved but further progress in understanding the underlying mechanisms and in preventing and treating the disease are important goals for the near future.


2015 ◽  
Vol 8 (3) ◽  
pp. 276-283
Author(s):  
Travis L. Almquist ◽  
Katie L. Wirt ◽  
Jason W. Adams ◽  
Rodney G. Lym

AbstractYellow toadflax (Linaria vulgaris P. Mill.) infestations in North Dakota increased 300-fold from 1997 to 2011, when the plant was added to the state noxious weed list. Long-term control of other invasive species had included biological control agents, but no effective agents for yellow toadflax had been identified, so a control program using herbicides was needed. The objective was to shift from short-term control with picloram applied in the fall at maximum allowed rates to long-term management with minimal nontarget species impact with an adaptive management approach. Yellow toadflax control was increased from an average of 64% with picloram at 1,120 g ha−1 alone 12 mo after treatment (MAT) to over 90% when applied with diflufenzopyr while the picloram rate was reduced 50%. Yellow toadflax control with aminocyclopyrachlor applied at 140 g ha−1 ranged from 91 to 49% 12 MAT when applied in June or September, respectively. In contrast, yellow toadflax control with picloram plus dicamba plus diflufenzopyr averaged > 90% regardless of application date during the growing season. Land managers now have at least two options for long-term yellow toadflax control with a wide window of application timing. The goal of replacing a single high-use–rate herbicide treatment was met but both picloram and aminocyclopyrachlor can injure many desirable forbs. However, application timing can now be adjusted to have the least impact on nontarget species. The adaptive development program led to a 58% reduction in yellow toadflax infestations in North Dakota by 2014.


2011 ◽  
Vol 279 (1733) ◽  
pp. 1560-1566 ◽  
Author(s):  
Lee Koren ◽  
Shinichi Nakagawa ◽  
Terry Burke ◽  
Kiran K. Soma ◽  
Katherine E. Wynne-Edwards ◽  
...  

Potential mechanistic mediators of Darwinian fitness, such as stress hormones or sex hormones, have been the focus of many studies. An inverse relationship between fitness and stress or sex hormone concentrations has been widely assumed, although empirical evidence is scarce. Feathers gradually accumulate hormones during their growth and provide a novel way to measure hormone concentrations integrated over time. Using liquid chromatography–tandem mass spectrometry, we measured testosterone, corticosterone and cortisol in the feathers of house sparrows ( Passer domesticus ) in a wild population which is the subject of a long-term study. Although corticosterone is considered the dominant avian glucocorticoid, we unambiguously identified cortisol in feathers. In addition, we found that feathers grown during the post-nuptial moult in autumn contained testosterone, corticosterone and cortisol levels that were significantly higher in birds that subsequently died over the following winter than in birds that survived. Thus, feather steroids are candidate prospective biomarkers to predict the future survival of individuals in the wild.


2005 ◽  
Vol 83 (9) ◽  
pp. 1257-1263 ◽  
Author(s):  
T D Lohuis ◽  
T D.I Beck ◽  
H J Harlow

Blood samples were drawn from six black bears (Ursus americanus Pallas, 1780) active in the summer and six others in early and late hibernation. Plasma urea:creatinine ratios and concentrations of amino acids, alanine aminotransferase, and aspartate aminotransferase dropped during the winter denning season, suggesting a decreased protein breakdown. Fifteen amino acids (3 branched chain and 12 glucogenic) were lower in the early winter than in the summer, but 6 of these amino acids rose back to summer levels by the late denning season. Hydroxyproline and glycine were also elevated during late winter, suggesting an increase in collagen breakdown. This profile suggests a dynamic process of adaptive fasting and protein conservation during the winter with a mobilization of non-myofibrilar collagen and perhaps smooth muscle protein reserves to augment a potential but slight increased breakdown of skeletal muscle during the late winter.


Blood ◽  
2014 ◽  
Vol 124 (3) ◽  
pp. 363-373 ◽  
Author(s):  
Shernan G. Holtan ◽  
Marcelo Pasquini ◽  
Daniel J. Weisdorf

Abstract Over the past 5 years, many novel approaches to early diagnosis, prevention, and treatment of acute graft-versus-host disease (aGVHD) have been translated from the bench to the bedside. In this review, we highlight recent discoveries in the context of current aGVHD care. The most significant innovations that have already reached the clinic are prophylaxis strategies based upon a refinement of our understanding of key sensors, effectors, suppressors of the immune alloreactive response, and the resultant tissue damage from the aGVHD inflammatory cascade. In the near future, aGVHD prevention and treatment will likely involve multiple modalities, including small molecules regulating immunologic checkpoints, enhancement of suppressor cytokines and cellular subsets, modulation of the microbiota, graft manipulation, and other donor-based prophylaxis strategies. Despite long-term efforts, major challenges in treatment of established aGVHD still remain. Resolution of inflammation and facilitation of rapid immune reconstitution in those with only a limited response to corticosteroids is a research arena that remains rife with opportunity and urgent clinical need.


1976 ◽  
Vol 21 (3) ◽  
pp. 139-148 ◽  
Author(s):  
C. D. Marsden

The treatment of Parkinson's disease today is complex, time-consuming, but rewarding. The introduction of levodopa has not cured the disease, but has provided the most powerful therapy available yet. Its use is limited by side effects and careful titration to optimum dosage, often in combination with other drugs, is required. Despite best therapy, some patients never respond, and others begin to lose benefit after some years of therapy. New problems, such as the ‘on-off’ effect have appeared with long-term treatment, and require careful adjustment of dosage. As with any replacement therapy, a balance between sub-optimal benefit and side effects has to be discovered and maintained by careful and frequent review. New approaches to treatment may offer further improvement in the near future.


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