New Metabolizable Immunologic Adjuvant for Human Use. 2. Short-term Animal Toxicity Tests

1964 ◽  
Vol 116 (2) ◽  
pp. 523-530 ◽  
Author(s):  
H. M. Peck ◽  
A. F. Woodhour ◽  
D. P. Metzgar ◽  
S. E. McKinney ◽  
M. R. Hilleman
2005 ◽  
Vol 22 (10) ◽  
pp. 1032-1041 ◽  
Author(s):  
I. Severin ◽  
L. Dahbi ◽  
J. -C. Lhuguenot ◽  
M. A. Andersson ◽  
D. Hoornstra ◽  
...  

2016 ◽  
Vol 371 (1703) ◽  
pp. 20150312 ◽  
Author(s):  
Casey M. Ryan ◽  
Rose Pritchard ◽  
Iain McNicol ◽  
Matthew Owen ◽  
Janet A. Fisher ◽  
...  

Miombo and mopane woodlands are the dominant land cover in southern Africa. Ecosystem services from these woodlands support the livelihoods of 100 M rural people and 50 M urban dwellers, and others beyond the region. Provisioning services contribute $9 ± 2 billion yr −1 to rural livelihoods; 76% of energy used in the region is derived from woodlands; and traded woodfuels have an annual value of $780 M. Woodlands support much of the region's agriculture through transfers of nutrients to fields and shifting cultivation. Woodlands store 18–24 PgC carbon, and harbour a unique and diverse flora and fauna that provides spiritual succour and attracts tourists. Longstanding processes that will impact service provision are the expansion of croplands (0.1 M km 2 ; 2000–2014), harvesting of woodfuels (93 M tonnes yr −1 ) and changing access arrangements. Novel, exogenous changes include large-scale land acquisitions (0.07 M km 2 ; 2000–2015), climate change and rising CO 2 . The net ecological response to these changes is poorly constrained, as they act in different directions, and differentially on trees and grasses, leading to uncertainty in future service provision. Land-use change and socio-political dynamics are likely to be dominant forces of change in the short term, but important land-use dynamics remain unquantified. This article is part of the themed issue ‘Tropical grassy biomes: linking ecology, human use and conservation’.


2010 ◽  
Vol 26 (4) ◽  
pp. 217-228 ◽  
Author(s):  
Simon Lukančič ◽  
Uroš Žibrat ◽  
Tadej Mezek ◽  
Andreja Jerebic ◽  
Tatjana Simčič ◽  
...  

A reliable method is needed for assessing the condition of aquatic animals and their resistance to toxic pollutants. The physiological responses of two freshwater crustaceans, Asellus aquaticus and Gammarus fossarum, following in vitro exposure to two pesticides (atrazine and imidacloprid), were measured by a combination of electron transport system (ETS) activity and respiration (R). Short-term exposure concentrations were selected according to standard toxicity tests and ranged from 0.01 mg L—1 to 10 mg L—1. When pesticide concentration was greater than 1 mg l— 1 (which is below the LC50 [48 hours] determined for both species), A. aquaticus and G. fossarum responded to short-term exposure with elevated levels of R and/or lower levels of ETS activity. One hour exposure to concentrations of up to 10 mg L—1 showed an effect in both test species. Laboratory tests confirmed that G. fossarum is more sensitive to short-term pesticide exposure than A. aquaticus. The combination of these two methods provides a useful and effective tool for assessing the general condition of aquatic animals. It also enables to determine toxic effects on freshwater biota of specific or combined pollutants. ETS/R ratio may be used as a quick predictor of effects on organisms exposed to pesticides and other stress factors such as changes in temperature, light, salinity, oxygen concentration and food.


1993 ◽  
Vol 9 ◽  
pp. 1-17 ◽  
Author(s):  
Gün Kut

The world's natural freshwater resources available for human use are more scarce than is generally assumed. This statement has already become a cliche, yet the truth it reveals is getting more apparent every day, just as is the case with other global problems which require solutions above and beyond the parochial and short term interests of individual nation states. Water scarcity has two important aspects, both with political connotations at different levels, with worldwide maldistribution of economic and natural resources being at the core of the problem.


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