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Biodiversity and the science that addresses its conservation, loss, and recovery, including conservation biology and restoration ecology, are high on the contemporary global agenda. While the hospitality industry has taken major steps toward net carbon zero and even net positive business, we argue that it has another significant advance to make. The United Nations has dedicated 2021–2030 as the decade of ecosystem restoration, and along with it, several other organizations offer guidance on how businesses should approach the natural environment. Considering the role of hospitality as a consumer of nature, we call for the industry to implement these principles in practice through nature-based solutions and restorative and regenerative hospitality. To strengthen this transformation, we urge hospitality management education to include the basic concepts of ecology, biodiversity, and environmental science, along with their application, in curricula. By doing this, education can advance from presenting sustainability actions as a necessity into illustrating and justifying their need on a planetary scale. The change will facilitate the next step the hospitality industry must take in transforming its relationship with the natural environment. [ABSTRACT FROM AUTHOR]

Abstract Background The continued depletion of tropical rainforests and fragmentation of natural habitats has led to significant ecological changes which place most top carnivores under heavy pressure. Various methods have been used to determine the status of top carnivore populations in rainforest habitats, most of which are costly in terms of equipment and time. In this study we utilized, for the first time, a rigorous track classification method to estimate population size and density of clouded leopards (Neofelis nebulosa) in Tabin Wildlife Reserve in north-eastern Borneo (Sabah). Additionally, we extrapolated our local-scale results to the regional landscape level to estimate clouded leopard population size and density in all of Sabah's reserves, taking into account the reserves' conservation status (totally protected or commercial forest reserves), their size and presence or absence of clouded leopards. Results The population size in the 56 km2 research area was estimated to be five individuals, based on a capture-recapture analysis of four confirmed animals differentiated by their tracks. Extrapolation of these results led to density estimates of nine per 100 km2 in Tabin Wildlife Reserve. The true density most likely lies between our approximately 95 % confidence interval of eight to 17 individuals per 100 km2. Conclusion We demonstrate that previous density estimates of 25 animals/100 km2 most likely overestimated the true density. Applying the 95% confidence interval we calculated in total a very rough number of 1500–3200 clouded leopards to be present in Sabah. However, only 275–585 of these animals inhabit the four totally protected reserves that are large enough to hold a long-term viable population of > 50 individuals.

We studied the social system and time budget of kob antelopes in the Comoé National Park, Côte d'Ivoire from March 1993 till May 1998, a population that is suffering from heavy over-hunting, to assess information about the effects of population decrease and its relevance for conservation of this antelope population. Single animals accounted for the majority of observed kob antelopes. Time allocated to certain behavioural traits depended on group size, with animals in smaller units spending less time on behaviours sensitive to predation risk. Single animals allocated far less time to ruminating and feeding being more vigilant and walking more. Groups were highly fluid and associations between individuals could be predicted by home-range overlap among females but not for female/male associations where association indices might be influenced by reproductive aims. Frequency of social groupings did not change compared with earlier studies when population density was much higher. However, compared with these studies maximum group size decreased, and smaller groups became more abundant. The observed effect of group size on the time budget of kob antelopes in combination with a steady decrease in group size because of reduction in population size might have a severe impact on the long-term persistence of the studied kob population due to anticipated aggravated predation effects. As males form the majority of single animals, putting them on higher predation risk, number of males decreases more rapidly than the number of females, which might eventually lead to a collapse of the kob population. Résumé Nous avons étudié le système social et l'emploi du temps des antilopes cobes dans le Parc National de Comoé, en Côte d'Ivoire, entre mars 1993 et mai 1995. C'est une population qui souffre d'une grave sur-chasse, et nous voulions évaluer les informations sur les effets de la diminution de la population et leur pertinence par rapport à la conservation de cette population d'antilopes. La majorité des observations de cobes concernaient des animaux solitaires. Le temps consacréà différents types de comportement dépendait de la taille du groupe, les animaux faisant partie des plus petits groupes allouant moins de temps à des comportements sensibles au risque de prédation. Les animaux isolés passaient beaucoup moins de temps à ruminer et à se nourrir car ils étaient plus vigilants et se déplaçaient davantage. Les groupes étaient très fluides, et on pouvait prévoir les associations entre individus femelles par le recouvrement de l'occupation spatiale des femelles, mais pour les associations mâles-femelles, les indices peuvent être influencés par des buts reproducteurs. La fréquence des regroupements sociaux n'a pas changé par rapport aux études antérieures, quand la densité de la population était beaucoup plus élevée. Cependant, par rapport à ces études, la taille maximale du groupe a diminué, et les plus petits groupes sont plus abondants. L'effet observé de la taille du groupe sur le budget temporel des antilopes cobes, combinéà la diminution très nette de la taille des groupes due à la réduction de la taille de la population, pourrait avoir un impact sévère sur la persistance à long terme de la population étudiée car on peut s'attendre à des effets plus graves de la prédation. Comme les mâles forment la majorité des individus solitaires, ce qui les met plus en danger face aux prédateurs, le nombre de mâles diminue plus vite que celui des femelles, ce qui pourrait conduire à l'effondrement de la population de cobes. [ABSTRACT FROM AUTHOR]

At least two splice variants of GLT-1 are expressed by rat brain astrocytes, albeit in different membrane domains. There is at present only limited data available as to the spatial relationship of such variants relative to the location of synapses and their functional properties. We have characterized the transport properties of GLT-1v in a heterologous expression system and conclude that its transport properties are similar to those of the originally described form of GLT-1, namely GLT-1alpha. We demonstrate that GLT-1alpha is localized to glial processes, some of which are interposed between multiple synapse types, including GABAergic synapses, whereas GLT-1v is expressed by astrocytic processes, at sites not interposed between synapses. Both splice variants can be expressed by a single astrocyte, but such expression is not uniform over the surface of the astrocytes. Neither splice variant of GLT-1 is evident in brain neurons, but both are abundantly expressed in some retinal neurons. We conclude that GLT-1v may not be involved in shaping the kinetics of synaptic signaling in the brain, but may be critical in preventing spillover of glutamate between adjacent synapses, thereby regulating intersynaptic glutamatergic and GABAergic transmission. Furthermore, GLT-1v may be crucial in ensuring that low levels of glutamate are maintained at extrasynaptic locations, especially in pathological conditions such as ischemia, motor neurone disease, and epilepsy., (Copyright 2003 Wiley-Liss, Inc.)

Purpose: Many strains of mutant mice die at birth, when the retina is still very immature. The retinas of such mice can be studied in organotypic cultures. After a preceding anatomic study of the synaptic development, the electrical activity of the synaptic circuits within such cultures was studied in wild-type and gephyrin-deficient mice., Methods: Organotypic cultures of newborn mouse retinas were grown for 14 days in vitro. Spontaneous postsynaptic currents (sPSCs) of amacrine cells were measured by using the whole-cell configuration of the patch-clamp technique. GABAergic and glycinergic currents that were isolated with specific antagonists, and retinas from wild-type (geph(+/+)) and gephyrin-deficient (geph(-/-)) mice were compared., Results: Rapidly decaying sPSCs that were blocked by kynurenic acid were mediated by ionotropic glutamate receptors, whereas sPSCs with significantly higher peak amplitudes and slow-decay kinetics were identified as spontaneous inhibitory postsynaptic currents (sIPSCs) mediated by gamma-aminobutyric acid type A receptors (GABA(A)Rs) and glycine receptors (GlyRs). In gephyrin-deficient (geph(-/-)) cultures, we found no sIPSCs mediated by GlyRs. sIPSCs mediated by GABA(A)Rs expressed in amacrine cells of geph(-/-) retinas decayed significantly faster than GABAergic sIPSCs recorded in amacrine cells of geph(+/+) retinas., Conclusions: The different decay kinetics of GABA(A)Rs expressed in amacrine cells of geph(+/+) and of geph(-/-) retinas suggests that these cells express at least two types of GABA(A)R subtypes. In amacrine cells of geph(-/-) mice, a specific GABA(A)R subtype that may contain the alpha2 subunit, is impaired by the absence of gephyrin, whereas other GABA(A)Rs appear to function normally.

beta-Site APP-cleaving enzyme (BACE) initiates the processing of the amyloid precursor protein (APP) leading to the generation of beta-amyloid, the main component of Alzheimer's disease senile plaques. BACE (Asp2, memapsin 2) is a type I transmembrane aspartyl protease and is responsible for the beta-secretase cleavage of APP producing different endoproteolytic fragments referred to as the carboxy-terminal C99, C89 and the soluble ectodomain sAPPbeta. Here we describe two transgenic mouse lines expressing human BACE in the brain. Overexpression of BACE augments the amyloidogenic processing of APP as demonstrated by decreased levels of full-length APP and increased levels of C99 and C89 in vivo. In mice expressing huBACE in addition to human APP wild-type or carrying the Swedish mutation, the induction of APP processing characterized by elevated C99, C89 and sAPPbeta, results in increased brain levels of beta-amyloid peptides Abeta40 and Abeta42 at steady-state.