Corporate Governance in the Cause of Peace: An Environmental Perspective

http://deepblue.lib.umich.edu/bitstream/2027.42/39814/3/wp430.pd

Business Law and the Legal Environment

https://digitalcommons.sacredheart.edu/opentexts/1000/thumbnail.jp

Predator-induced defences in Daphnia pulex: Selection and evaluation of internal reference genes for gene expression studies with real-time PCR

<p>Abstract</p> <p>Background</p> <p>The planktonic microcrustacean <it>Daphnia pulex </it>is among the best-studied animals in ecological, toxicological and evolutionary research. One aspect that has sustained interest in the study system is the ability of <it>D. pulex </it>to develop inducible defence structures when exposed to predators, such as the phantom midge larvae <it>Chaoborus</it>. The available draft genome sequence for <it>D. pulex </it>is accelerating research to identify genes that confer plastic phenotypes that are regularly cued by environmental stimuli. Yet for quantifying gene expression levels, no experimentally validated set of internal control genes exists for the accurate normalization of qRT-PCR data.</p> <p>Results</p> <p>In this study, we tested six candidate reference genes for normalizing transcription levels of <it>D. pulex </it>genes; alpha tubulin (aTub), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), TATA box binding protein (Tbp) syntaxin 16 (Stx16), X-box binding protein 1 (Xbp1) and CAPON, a protein associated with the neuronal nitric oxide synthase, were selected on the basis of an earlier study and from microarray studies. One additional gene, a matrix metalloproteinase (MMP), was tested to validate its transcriptional response to <it>Chaoborus</it>, which was earlier observed in a microarray study. The transcription profiles of these seven genes were assessed by qRT-PCR from RNA of juvenile <it>D. pulex </it>that showed induced defences in comparison to untreated control animals. We tested the individual suitability of genes for expression normalization using the programs geNorm, NormFinder and BestKeeper. Intriguingly, Xbp1, Tbp, CAPON and Stx16 were selected as ideal reference genes. Analyses on the relative expression level using the software REST showed that both classical housekeeping candidate genes (aTub and GAPDH) were significantly downregulated, whereas the MMP gene was shown to be significantly upregulated, as predicted. aTub is a particularly ill suited reference gene because five copies are found in the <it>D. pulex </it>genome sequence. When applying aTub for expression normalization Xbp1 and Tbp are falsely reported as significantly upregulated.</p> <p>Conclusions</p> <p>Our results suggest that the genes Xbp1, Tbp, CAPON and Stx16 are suitable reference genes for accurate normalization in qRT-PCR studies using <it>Chaoborus</it>-induced <it>D. pulex </it>specimens. Furthermore, our study underscores the importance of verifying the expression stability of putative reference genes for normalization of expression levels.</p

CO2-Zertifikate für die Festlegung atmosphärischen Kohlenstoffs in Böden: Methoden, Maßnahmen und Grenzen

Agrarböden besitzen durch den Aufbau von organsicher Bodensubstanz (Humus), die zu etwa 58% aus Kohlenstoff (Corg) besteht, ein großes Potential zur Kohlenstoffbindung. Positive Anstrengungen im Humusmanagement könnten daher einen wesentlichen Beitrag für den Klimaschutz leisten. Für Landwirtinnen und Landwirte stellen so genannte CO2-Zertifikate für den Aufbau von Corg („Humuszertifikate“) einen zusätzlichen Anreiz dar, humusfördernde Bewirtschaftungsmaßnahmen umzusetzen. Diese CO2-Zertifikate werden von privatwirtschaftlichen Initiativen und Unternehmen im Bereich des freiwilligen CO2-Markts vergeben. Insbesondere im Bereich der Landwirtschaft wächst im deutschsprachigen Raum derzeit der Zertifikatehandel für den Aufbau von Corg in Agrarböden. Um zum Klimaschutz beizutragen, müssen bei der Vergabe von Zertifikaten bestimmte Kriterien eingehalten werden. Wissenschaftliche Mindeststandards wurden dabei in der Praxis bislang jedoch wenig berücksichtigt. In dieser Studie werden Empfehlungen hinsichtlich der Erfassung von Corg (Probenahme, Analytik, Vorratsberechnung), eine Bewertung von Maßnahmen zum Corg-Aufbau, sowie Hinweise zu generellen Einschränkungen hinsichtlich des Klimaschutzes über CO2-Zertifikate gegeben. CO2-Zertifikate können einen positiven Anstoß geben, damit sich Landwirte verstärkt mit einer nachhaltigen Bewirtschaftung und Humusversorgung ihrer Böden auseinandersetzen. Da Humus die zentrale Steuergröße für viele Funktionen des Bodens und nicht zuletzt der Bodenfruchtbarkeit darstellt, ist jede Anstrengung für mehr Humus sinnvoll. Landwirtinnen und Landwirte, die sich für Humusaufbau interessieren, sollten daher hinsichtlich standort- und betriebsspezifischen Optionen zum Aufbau von Corg umfassend unterstützt und beraten werden

Suitability of soil carbon certificates for climate change mitigation

There is growing awareness of the role that agricultural soils can play for climate change mitigation. Agricultural management that increases soil organic carbon (SOC) stocks constitutes a nature-based solution for carbon dioxide removal. As soils store about twice the amount of carbon found in the atmosphere, even small relative increases could significantly reduce global warming. However, increasing SOC requires management changes that come with costs to the farmers. In this regard, soil carbon certificates could provide a much-needed financial incentive: Farmers register their fields with commercial providers who certify any SOC increase achieved during a set period of time. The certificates are then sold on the voluntary carbon-offset market. We analysed the suitability of soil carbon certificates for climate change mitigation from the perspectives of soil sciences, agricultural management, and governance. In particular, we addressed questions of quantification, additionality, permanence, changes in emissions, leakage effects, transparency, legitimacy and accountability, as well as synergies and trade-offs with other societal targets. Soil properties and the mechanisms by which carbon is stored in soils have strong implications for the assessment. Soils have a limited storage capacity, and SOC is not sequestered but its SOC stocks are the dynamic result of plant derived inputs and losses mainly in the form of microbial respiration. The higher the SOC stock, the higher the annual carbon inputs that is needed to maintain it. If carbon friendly management is discontinued, elevated SOC levels will therefore revert to their original level. We found that while changes in agricultural management that increase SOC are highly desirable and offer multiple-co benefits with climate change adaptation, soil carbon certificates are unsuitable as a tool. They are unlikely to deliver the climate change mitigation they promise as certificate providers cannot guarantee permanence and additionality of SOC storage over climate relevant time-frames. Where the certified carbon storage is non-permanent or fails to meet criteria of additionality, the use of such certificates to advertise products as “carbon-neutral” may be construed as false advertising

Carbon farming: Are soil carbon certificates a suitable tool for climate change mitigation?

Increasing soil organic carbon (SOC) stocks in agricultural soils removes carbon dioxide from the atmosphere and contributes towards achieving carbon neutrality. For farmers, higher SOC levels have multiple benefits, including increased soil fertility and resilience against drought-related yield losses. However, increasing SOC levels requires agricultural management changes that are associated with costs. Private soil carbon certificates could compensate for these costs. In these schemes, farmers register their fields with commercial certificate providers who certify SOC increases. Certificates are then sold as voluntary emission offsets on the carbon market. In this paper, we assess the suitability of these certificates as an instrument for climate change mitigation. From a soils' perspective, we address processes of SOC enrichment, their potentials and limits, and options for cost-effective measurement and monitoring. From a farmers’ perspective, we assess management options likely to increase SOC, and discuss their synergies and trade-offs with economic, environmental and social targets. From a governance perspective, we address requirements to guarantee additionality and permanence while preventing leakage effects. Furthermore, we address questions of legitimacy and accountability. While increasing SOC is a cornerstone for more sustainable cropping systems, private carbon certificates fall short of expectations for climate change mitigation as permanence of SOC sequestration cannot be guaranteed. Governance challenges include lack of long-term monitoring, problems to ensure additionality, problems to safeguard against leakage effects, and lack of long-term accountability if stored SOC is re-emitted. We conclude that soil-based private carbon certificates are unlikely to deliver the emission offset attributed to them and that their benefit for climate change mitigation is uncertain. Additional research is needed to develop standards for SOC change metrics and monitoring, and to better understand the impact of short term, non-permanent carbon removals on peaks in atmospheric greenhouse gas concentrations and on the probability of exceeding climatic tipping points

Targeting the TCA cycle can ameliorate widespread axonal energy deficiency in neuroinflammatory lesions

Inflammation in the central nervous system can impair the function of neuronal mitochondria and contributes to axon degeneration in the common neuroinflammatory disease multiple sclerosis (MS). Here we combine cell-type-specific mitochondrial proteomics with in vivo biosensor imaging to dissect how inflammation alters the molecular composition and functional capacity of neuronal mitochondria. We show that neuroinflammatory lesions in the mouse spinal cord cause widespread and persisting axonal ATP deficiency, which precedes mitochondrial oxidation and calcium overload. This axonal energy deficiency is associated with impaired electron transport chain function, but also an upstream imbalance of tricarboxylic acid (TCA) cycle enzymes, with several, including key rate-limiting, enzymes being depleted in neuronal mitochondria in experimental models and in MS lesions. Notably, viral overexpression of individual TCA enzymes can ameliorate the axonal energy deficits in neuroinflammatory lesions, suggesting that TCA cycle dysfunction in MS may be amendable to therapy

Targeting the TCA cycle can ameliorate widespread axonal energy deficiency in neuroinflammatory lesions

In this study, Tai et al. provide insights into the metabolic and bioenergetic responses in the axonal compartment in the context of multiple sclerosis. Moreover, they show how upregulating the tricarboxylic acid cycle confers protection against neuroinflammation-induced energy deprivation. Inflammation in the central nervous system can impair the function of neuronal mitochondria and contributes to axon degeneration in the common neuroinflammatory disease multiple sclerosis (MS). Here we combine cell-type-specific mitochondrial proteomics with in vivo biosensor imaging to dissect how inflammation alters the molecular composition and functional capacity of neuronal mitochondria. We show that neuroinflammatory lesions in the mouse spinal cord cause widespread and persisting axonal ATP deficiency, which precedes mitochondrial oxidation and calcium overload. This axonal energy deficiency is associated with impaired electron transport chain function, but also an upstream imbalance of tricarboxylic acid (TCA) cycle enzymes, with several, including key rate-limiting, enzymes being depleted in neuronal mitochondria in experimental models and in MS lesions. Notably, viral overexpression of individual TCA enzymes can ameliorate the axonal energy deficits in neuroinflammatory lesions, suggesting that TCA cycle dysfunction in MS may be amendable to therapy