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11.
The restoration community continues to discuss what constitutes good environmental stewardship. One area of tension is the extent to which the well‐being of wild animals should inform restoration efforts. We discuss three ways that the perspective of wild animal welfare can augment restoration ecology: strengthening people's relationship with nature, reinforcing biotic integrity, and reducing mechanistic uncertainty. The animal welfare movement elevates sentient animals as stakeholders and explores how environmental context directly impacts the well‐being of individuals. Viewing wild animals through this lens may encourage people to think and act with empathy and altruism. Second, we incorporate animal welfare into the concept of biotic integrity for ecological and ethical reasons. Restoring ecosystem processes may enhance animal welfare, and vice versa. Alternatively, there may be a trade‐off between these factors, requiring local decision‐makers to prioritize between restoring ecosystem function and promoting individuals' well‐being. We conclude by discussing how welfare can impact population recovery, thereby adding insights about mechanisms underpinning restoration objectives. Ultimately, restoration ecologists and proponents of wild animal welfare could enjoy a productive union. 相似文献
12.
A bioprocess for machine washable wool, combining the advantages of both protease and transglutaminase in a simultaneous enzymatic treatment has been developed. This process reduced the felting tendency of woven wool fabrics by 9% at the expense of only 2% weight and tensile strength loss. In contrast to previously described protease-based processes for shrink resistant wool, the anti-felting properties achieved in the simultaneous enzymatic treatment produced insignificant fibre damage, confirmed also by scanning electron images of the fabrics. 相似文献
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Alphaxolone-alphadolone anaesthesia in laboratory animals 总被引:1,自引:0,他引:1
The anaesthetic steroid combination alphaxolone-alphadolone is a well-established short-acting injectable agent for cats and primates. It can be recommended for intravenous administration to rats, rabbits, neonatal pigs, mice and hamsters. It has limited value in mice and hamsters by the intraperitoneal route, but provides sedation in ferrets and neonatal pigs when injected intramuscularly. It can be given repeatedly or continuously to maintain anaesthesia for long periods without the development of tolerance or cumulation. 相似文献
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Bruna Martins Bezerra Antonio da Silva Souto Lewis George Halsey Nicola Schiel 《Journal of Ethology》2008,26(1):175-178
Bradypus variegatus is a member of the Order Pilosa, Family Bradypodidae, and is distributed in many subtropical and tropical countries in South
and Central America. However, studies on this species in the wild are relatively limited and many aspects of its reproductive
behaviour are unknown or unclear. The current report presents new observations of the reproductive behaviour of B. variegatus in its natural environment. These include details of both a male–female copulation and the simultaneous nurturing of two young
sloths. 相似文献
17.
J F Hainfeld W Liu C M Halsey P Freimuth R D Powell 《Journal of structural biology》1999,127(2):185-198
Addition of six histidines to recombinant proteins has proved useful in their purification by nickel-affinity columns. This technology was adapted by synthesizing the chelator for nickel (nitrilotriacetic acid, NTA) onto the surface of gold clusters. These Ni-NTA-gold clusters were shown to specifically target the 6His region of tagged proteins. Results were verified by column chromatography, dot and overlay blots, UV-Vis spectroscopy, and scanning transmission electron microscopy. A 6His-tagged adenovirus "knob" protein was also shown to maintain receptor binding activity after gold labeling. Two types of gold clusters were used: 1.4-nm Nanogold and a new 1.8-nm "PeptideGold" coated with an NTA-dipeptide-thiol. These novel labels should be useful in site-specific high-resolution EM labeling, as well as in metallographic development, detection in the light microscope, or direct visualization. 相似文献
18.
Calcium channel antagonists decrease the ethanol withdrawal syndrome 总被引:13,自引:0,他引:13
Withdrawal from chronic ethanol intake results in a syndrome of tremor and hyperexcitability, which can progress to seizures and death. Drugs used therapeutically to alleviate the syndrome have sedative actions and dependence liability of their own. The basis of the syndrome is unclear, although ethanol affects many neuronal functions, including membrane calcium conductance. Calcium channel blocking drugs have been used in cardiovascular disorders; they bind to high affinity sites in the brain but have few overt actions on the central nervous system. We have tested the effects of four calcium channel antagonists on the ethanol withdrawal syndrome in rats. Nitrendipine and nimodipine abolished all spontaneous seizures and prevented or reduced seizures following an audiogenic stimulus, and mortality. Verapamil significantly decreased seizure incidence and both it and flunarizine lowered mortality. The dihydropyridines were considerably more effective than diazepam in the withdrawal syndrome but had little effect on pentylenetetrazol seizures, against which diazepam gave good protection. The calcium channel inhibitors showed no sedative activity in normal animals. The results provide evidence that alterations in calcium conductance may be involved in the ethanol withdrawal syndrome and offer possibilities for the development of non-sedative therapeutic treatment of this syndrome. 相似文献
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Models of diving optimality qualitatively predict diving behaviours of aquatic birds and mammals. However, none of them has been empirically tested. We examined the quantitative predictions of optimal diving models by combining cumulative oxygen uptake curves with estimates of power costs during the dives of six tufted ducks, Aythya fuligula. The effects of differing foraging costs on dive duration and rate of oxygen uptake (VO2up) at the surface were measured during bouts of voluntary dives to a food tray. The birds were trained to surface into a respirometer after each dive, so that changes in VO2up over time could be measured. The tray held either just food or closely packed stones on top of the food to make foraging energetically more costly. In contrast to predictions from the Houston & Carbone model, foraging time (tf) increased after dives incorporating higher foraging energy costs but surface time (ts) remained the same. While optimal diving models have assumed that the cumulative oxygen uptake curve is fixed, VO2up increased when the energy cost of the dive increased. The optimal breathing model quantitatively predicted ts in both conditions and oxygen consumption during foraging (m2tf) in the control condition, for the mean of all ducks. This offers evidence that the ducks were diving optimally and supports the fundamentals of optimal diving theory. However, the model did not consistently predictts or m2tf for individual birds. We discuss the limits of optimal foraging models for air-breathing divers caused by individual variation. Copyright 2003 Published by Elsevier Science Ltd on behalf of The Association for the Study of Animal Behaviour. 相似文献
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