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Coronavirus disease 2019 (COVID-19) has shown high infection and mortality rates all over the world, and despite the global efforts, there is so far no specific therapy available for COVID-19. Interestingly, while the severity and mortality of COVID-19 are higher in males than in females, the underlying molecular mechanisms are unclear. In this review, we explore sex-related differences that may be contributing factors to the observed male-biased mortality from COVID-19. Males are considered the weaker sex in aspects related to endurance and infection control. Studies show that viral RNA clearance is delayed in males with COVID-19. A recent study has indicated that the testis can harbor coronavirus, and consequently, males show delayed viral clearance. However, the role of testis involvement in COVID-19 severity and mortality needs further research. Males and females show a distinct difference in immune system responses with females eliciting stronger immune responses to pathogens. This difference in immune system responses may be a major contributing factor to viral load, disease severity, and mortality. In addition, differences in sex hormone milieus could also be a determinant of viral infections as estrogen has immunoenhancing effects while testosterone has immunosuppressive effects. The sex-specific severity of COVID-19 infections indicates that further research on understanding the sex differences is needed. Inclusion of both males and females in basic research and clinical trials is required to provide critical information on sex-related differences that may help to better understand disease outcome and therapy.

Miniaturized thermal infrared (TIR) cameras that measure surface temperature are increasingly available for use with unmanned aerial vehicles (UAVs). However, deriving accurate temperature data from these cameras is non-trivialsince they are highly sensitive to changes in their internal temperature and low-cost models are often not radiometrically calibrated. We present the results of laboratory and field experiments that tested the extent of the temperature-dependency of a non-radiometric FLIR Vue Pro 640. We found that a simple empirical line calibration using at least three ground calibration points was sufficient to convert camera digital numbers to temperature values for images captured during UAV flight. Although the camera performed well under stable laboratory conditions (accuracy ±0.5 °C), the accuracy declined to ±5 °C under the changing ambient conditions experienced during UAV flight. The poor performance resulted from the non-linear relationship between camera output and sensor temperature, which was affected by wind and temperature-drift during flight. The camera’s automated non-uniformity correction (NUC) could not sufficiently correct for these effects. Prominent vignetting was also visible in images captured under both stable and changing ambient conditions. The inconsistencies in camera output over time and across the sensor will affect camera applications based on relative temperature differences as well as user-generated radiometric calibration. Based on our findings, we present a set of best practices for UAV TIR camera sampling to minimize the impacts of the temperature dependency of these systems.

Scholars and policy makers are becoming increasingly interested in the processes that lead to transformations toward sustainability. We explored how resilience thinking, and a stronger focus on social-ecological systems, can contribute to existing studies of sustainability transformations. First, we responded to two major points of critique: the claim that resilience theory is not useful for addressing sustainability transformations, and that the role of “power” in transformation processes has been underplayed by resilience scholars. Second, we highlighted promising work that combines insights from different theoretical strands, a strategy that strengthens our understanding of sustainability transformations. We elaborated three research areas on which such combined perspectives could focus: innovation and social-ecological-technological systems interactions, patterns of transformation, and agency and transformation.

Significance Adaptive governance (AG) has been suggested as a suitable approach for ecosystem management in changing environments. It rests on the assumption that landscapes and seascapes need to be understood and governed as complex social–ecological systems rather than as ecosystems alone. We compared three AG initiatives and their effects on natural capital and ecosystem services. In comparison with other efforts aimed at conservation and sustainable use of natural capital, adaptive governance developed capacity to manage multiple ecosystem services and respond to ecosystem-wide changes and enabled collaboration across diverse interests, sectors, and institutional arrangements. Internal and external pressures continuously challenge the adaptive capacity of the initiatives. To gain insights into the effects of adaptive governance on natural capital, we compare three well-studied initiatives; a landscape in Southern Sweden, the Great Barrier Reef in Australia, and fisheries in the Southern Ocean. We assess changes in natural capital and ecosystem services related to these social–ecological governance approaches to ecosystem management and investigate their capacity to respond to change and new challenges. The adaptive governance initiatives are compared with other efforts aimed at conservation and sustainable use of natural capital: Natura 2000 in Europe, lobster fisheries in the Gulf of Maine, North America, and fisheries in Europe. In contrast to these efforts, we found that the adaptive governance cases developed capacity to perform ecosystem management, manage multiple ecosystem services, and monitor, communicate, and respond to ecosystem-wide changes at landscape and seascape levels with visible effects on natural capital. They enabled actors to collaborate across diverse interests, sectors, and institutional arrangements and detect opportunities and problems as they developed while nurturing adaptive capacity to deal with them. They all spanned local to international levels of decision making, thus representing multilevel governance systems for managing natural capital. As with any governance system, internal changes and external drivers of global impacts and demands will continue to challenge the long-term success of such initiatives.

Using path analysis, we investigate the direct and indirect links between three measures of earnings quality and the cost of equity. Our investigation is motivated by analytical models that specify both a direct link and an indirect link that is mediated by information asymmetry, but do not suggest which link would be more important empirically. We measure information asymmetry as both the adverse selection component of the bid-ask spread and the probability of informed trading (PIN). For a large sample of Value Line firms during 1993–2005, we find statistically reliable evidence of both a direct path from earnings quality to the cost of equity, and an indirect path that is mediated by information asymmetry, with the weight of the evidence favoring the direct path as the more important.

Metal contamination of aquatic environments remains a major concern due to their persistence. The water flea Daphnia magna is an important model species for metal toxicity studies and water quality assessment. However, most research has focused on physiological endpoints such as mortality, growth, and reproduction in laboratory settings, as well as neglected toxicogenomic responses. Copper (Cu) and zinc (Zn) are essential trace elements that play crucial roles in many biological processes, including iron metabolism, connective tissue formation, neurotransmitter synthesis, DNA synthesis, and immune function. Excess amounts of these metals result in deviations from homeostasis and may induce toxic responses. In this study, we analyzed Daphnia magna transcriptomic responses to IC 5 levels of Cu (120 µg/L) and Zn (300 µg/L) in environmental water obtained from a pristine lake with adjusted water hardness (150 mg/L CaCO 3 ). The study was carried out to gain insights into the Cu and Zn regulated stress response mechanisms in Daphnia magna at transcriptome level. A total of 2,688 and 3,080 genes were found to be differentially expressed (DEG) between the control and Cu and the control and Zn, respectively. There were 1,793 differentially expressed genes in common for both Cu and Zn, whereas the number of unique DEGs for Cu and Zn were 895 and 1,287, respectively. Gene ontology and KEGG pathways enrichment were carried out to identify the molecular functions and biological processes affected by metal exposures. In addition to well-known biomarkers, novel targets for metal toxicity screening at the genomic level were identified.

We investigate the relations among voluntary disclosure, earnings quality, and cost of capital. We find that firms with good earnings quality have more expansive voluntary disclosures (as proxied by a self-constructed index of coded items found in 677 firms' annual reports and 10-K filings in fiscal 2001) than firms with poor earnings quality. In unconditional tests, we find that more voluntary disclosure is associated with a lower cost of capital. However, consistent with the complementary association between disclosure and earnings quality, we find that the disclosure effect on cost of capital is substantially reduced or disappears completely (depending on the cost of capital proxy) once we condition on earnings quality. Extensions probing alternative proxies show that our findings are robust to measures of earnings quality and cost of capital, but not to other measures of voluntary disclosure. In particular, we find opposite relations for voluntary disclosure measures based on management forecasts and conference calls, and we find no relations for a press release based measure.

Background Mating behavior differ between sexes and involves gonadal hormones and possibly sexually dimorphic gene expression in the brain. Sex steroids and prostaglandin E 2 (PGE 2 ) have been shown to regulate mammalian sexual behavior. The present study was aimed at determining whether exposure to sex steroids and prostaglandins could alter zebrafish sexual mating behavior. Methods Mating behavior and successful spawning was recorded following exposure to 17β-estradiol (E2), 11-ketotestosterone (11-KT), prostaglandin D 2 (PGD 2 ) and PGE 2 via the water. qRT-PCR was used to analyze transcript levels in the forebrain, midbrain, and hindbrain of male and female zebrafish and compared to animals exposed to E2 via the water. Results Exposure of zebrafish to sex hormones resulted in alterations in behavior and spawning when male fish were exposed to E2 and female fish were exposed to 11-KT. Exposure to PGD 2, and PGE 2 did not alter mating behavior or spawning success. Determination of gene expression patterns of selected genes from three brain regions using qRT-PCR analysis demonstrated that the three brain regions differed in gene expression pattern and that there were differences between the sexes. In addition, E2 exposure also resulted in altered gene transcription profiles of several genes. Conclusions Exposure to sex hormones, but not prostaglandins altered mating behavior in zebrafish. The expression patterns of the studied genes indicate that there are large regional and gender-based differences in gene expression and that E2 treatment alter the gene expression pattern in all regions of the brain.

We reviewed the literature on leadership in linked social-ecological systems and combined it with the literature on institutional entrepreneurship in complex adaptive systems to develop a new theory of transformative agency in linked social-ecological systems. Although there is evidence of the importance of strategic agency in introducing innovation and transforming approaches to management and governance of such systems, there is no coherent theory to explain the wide diversity of strategies identified. Using Holling’s adaptive cycle as a model of phases present in innovation and transformation of resilient social-ecological systems, overlaid by Dorado’s model of opportunity context (opaque, hazy, transparent) in complex adaptive systems, we propose a more coherent theory of strategic agency, which links particular strategies, on the part of transformative agents, to phases of system change.

Unmanned aerial systems (UAS) carrying commercially sold multispectral sensors equipped with a sunshine sensor, such as Parrot Sequoia, enable mapping of vegetation at high spatial resolution with a large degree of flexibility in planning data collection. It is, however, a challenge to perform radiometric correction of the images to create reflectance maps (orthomosaics with surface reflectance) and to compute vegetation indices with sufficient accuracy to enable comparisons between data collected at different times and locations. Studies have compared different radiometric correction methods applied to the Sequoia camera, but there is no consensus about a standard method that provides consistent results for all spectral bands and for different flight conditions. In this study, we perform experiments to assess the accuracy of the Parrot Sequoia camera and sunshine sensor to get an indication if the quality of the data collected is sufficient to create accurate reflectance maps. In addition, we study if there is an influence of the atmosphere on the images and suggest a workflow to collect and process images to create a reflectance map. The main findings are that the sensitivity of the camera is influenced by camera temperature and that the atmosphere influences the images. Hence, we suggest letting the camera warm up before image collection and capturing images of reflectance calibration panels at an elevation close to the maximum flying height to compensate for influence from the atmosphere. The results also show that there is a strong influence of the orientation of the sunshine sensor. This introduces noise and limits the use of the raw sunshine sensor data to compensate for differences in light conditions. To handle this noise, we fit smoothing functions to the sunshine sensor data before we perform irradiance normalization of the images. The developed workflow is evaluated against data from a handheld spectroradiometer, giving the highest correlation (R2 = 0.99) for the normalized difference vegetation index (NDVI). For the individual wavelength bands, R2 was 0.80–0.97 for the red-edge, near-infrared, and red bands.