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Human land-use intensification threatens arthropod (for example, insect and spider) biodiversity across aquatic and terrestrial ecosystems. Insects and spiders play critical roles in ecosystems by accumulating and synthesizing organic nutrients such as polyunsaturated fatty acids (PUFAs). However, links between biodiversity and nutrient content of insect and spider communities have yet to be quantified. We relate insect and spider richness to biomass and PUFA-mass from stream and terrestrial communities encompassing nine land uses. PUFA-mass and biomass relate positively to biodiversity across ecosystems. In terrestrial systems, human-dominated areas have lower biomass and PUFA-mass than more natural areas, even at equivalent levels of richness. Aquatic ecosystems have consistently higher PUFA-mass than terrestrial ecosystems. Our findings reinforce the importance of conserving biodiversity and highlight the distinctive benefits of aquatic biodiversity. [ABSTRACT FROM AUTHOR]

Europe's semi-natural grasslands support notably high levels of temperate biodiversity across multiple taxonomic groups. However, these ecosystems face unique conservation challenges. Contemporary agricultural practices have replaced historical traditional low-intensity agriculture in many regions, resulting in a spectrum of management intensities within these ecosystems, ranging from highly intensive methods to complete abandonment. Paradoxically, both extremes along this spectrum of management intensity can be detrimental to biodiversity of semi-natural grasslands. Moreover, while anthropogenic climate change is an overarching threat to these ecosystems, rapid changes in land use and its intensity often present more immediate pressures. Often occurring at a faster rate than climate change itself, these land-use changes have the potential to rapidly impact the biodiversity of these grasslands. Here, we divide the ecological processes, threats, and developments to semi-natural grasslands into three sections. First, we examine the different impacts of agricultural intensification and abandonment on these ecosystems, considering their different consequences for biodiversity. Second, we review seminal works on various evidence-based management practices and offer a concise summary that provides support for various conservation and management strategies. However, the socio-economic factors that drive both abandonment and intensification in semi-natural grasslands can also be used to develop solutions through strategic governmental and non-governmental interventions. Accordingly, we conclude with a way forward by providing several key policy recommendations. By synthesizing existing knowledge and identifying research gaps, this essay aims to provide valuable insights for advancing the sustainable management of semi-natural grasslands. The biodiversity of Europe's semi-natural grasslands is threatened by contemporary agricultural intensification and abandonment. Shipley et al. explore these threats, review management practices, and offer policy recommendations to support sustainable conservation efforts. [ABSTRACT FROM AUTHOR]

Understanding how animals meet their daily energy requirements is critical in our rapidly changing world. Small organisms with high metabolic rates can conserve stored energy when food availability is low or increase energy intake when energetic requirements are high, but how they balance this in the wild remains largely unknown. Using miniaturized heart rate transmitters, we continuously quantified energy expenditure, torpor use and foraging behaviour of free-ranging male bats (Nyctalus noctula) in spring and summer. In spring, bats used torpor extensively, characterized by lowered heart rates and consequently low energy expenditures. In contrast, in summer, bats consistently avoided torpor, even though they could have used this low-energy mode. As a consequence, daytime heart rates in summer were three times as high compared with the heart rates in spring. Daily energy use increased by 42% during summer, despite lower thermogenesis costs at higher ambient temperatures. Likely, as a consequence, bats nearly doubled their foraging duration. Overall, our results indicate that summer torpor avoidance, beneficial for sperm production and self-maintenance, comes with a high energetic cost. The ability to identify and monitor such vulnerable energetic life-history stages is particularly important to predict how species will deal with increasing temperatures and changes in their resource landscapes. [ABSTRACT FROM AUTHOR]

Metabolic processes of animals are often studied in controlled laboratory settings. However, these laboratory settings often do not reflect the animals' natural environment. Thus, results of metabolic measurements from laboratory studies must be cautiously applied to free-ranging animals. Recent technological advances in animal tracking allow detailed eco-physiological studies that reveal when, where, and how physiological measurements from the field differ from those from the laboratory. We investigated the torpor behavior of male common noctule bats (Nyctalus noctula) across different life history stages using two approaches: in controlled laboratory experiments and in the field using calibrated heart rate telemetry. We predicted that non-reproductive males would extensively use torpor to conserve energy, whereas reproductive males would reduce torpor use to promote spermatogenesis. We did not expect differences in torpor use between captive and wild animals as we simulated natural temperature conditions in the laboratory. We found that during the non-reproductive phase, both captive and free-ranging bats used torpor extensively. During reproduction, bats in captivity unexpectedly also used torpor throughout the day, while only free-ranging bats showed the expected reduction in torpor use. Thus, depending on life history stage, torpor behavior in the laboratory was markedly different from the wild. By implementing both approaches and at different life history stages, we were able to better explore the limitations of eco-physiological laboratory studies and make recommendations for when they are an appropriate proxy for natural behavior. [ABSTRACT FROM AUTHOR]

Surfactant proteins (SP)-A and -D are members of the collectin family of host defense proteins that share four distinct structural domains: N[H.sub.2]-terminal oligomerization, collagenous, neck, and carbohydrate recognition (CRD). To determine the specificity of the functions of these domains, the SFTPC promoter was used to express 1) full-length rat (r) Sftpa; 2) N[H.sub.2]-rSftpa/d, consisting of N[H.sub.2]-terminal and collagenous domains of SP-A with neck domain and CRD of SP-D; and 3) rSftpd/a, consisting of N[H.sub.2]-terminal and collagenous domains of SP-D with neck domain and CRD of SP-A, in [Sftpd.sup.-/-] mice. Increased expression of SP-A in [Sftpd.sup.-/-] mice did not correct the increased pulmonary saturated phosphatidylcholine levels, emphysema, or foamy alveolar macrophage and lymphocyte infiltrations characteristic of [Sfipd.sup.-/-] mice, indicating that the decreased SP-A level noted in [Sfipd.sup.-/-] mice does not account for the observed pulmonary abnormalities. The chimeric protein N[H.sub.2]-rSftpa/d was expressed and detected in the airways of transgenic mice, migrating as an SP-A-like oligomer that associated with large aggregate surfactant in a manner similar to that of SP-A rather than SP-D. N[H.sub.2]-rSftpa/d did not correct emphysema, foamy macrophage and lymphocyte infiltration, or the increased lipid accumulations characteristic of [Sftpd.sup.-/-] mice. Thus oligomerization and surfactant lipid association of SP-D requires its N[H.sub.2]-terminal and collagenous domains, which are needed for SP-D-dependent regulation of surfactant homeostasis in vivo. Attempts to express rSftpd/a fusion protein in vivo were unsuccessful. [Mmp9.sup.-/-]/[Sftpd.sup.-/-] and [Mmpl2.sup.-/-]/[Sftpd.sup.-/-] mice developed air space enlargement similar to [Sftpd.sup.-/-] mice, supporting the concept that the increased expression of each metalloproteinase seen in [Sftpd.sup.-/-] lungs is not the major cause of emphysema. [Sftpd.sup.-/-] mice; emphysema; lipid homeostasis; inflammation doi:10.1152/ajplung.00015.2006

The authors studied a potential drug-drug interaction via findings from in vitro and in vivo studies, to assess whether the in vitro system was predictive of in vivo clinical pharmacokinetic [...]