The ground‐based microwave radiometers GROMOS and MIAWARA at Bern (Switzerland) continuously measure ozone and water vapor profiles from 20 to 70 km altitude. A major sudden stratospheric warming occurred around 19 February 2008 with minimal temperatures of 189 K at 40 hPa and maximal temperatures of 300 K at 4 hPa. During the stratospheric warming the Swiss ground‐based radiometers observed a depletion of ozone and an enhancement of water vapor while NASA's CALIPSO satellite instrument measured a large PSC area over Europe. Ozone depletion in the lower stratosphere is explained by transport of ozone poor air from the cold polar vortex. The depletion of upper stratospheric ozone is caused by a sudden temperature increase of about 50 K. A simulation of a chemical box model confirms that a major fraction of the observed decrease of the ozone mixing ratio at 4 hPa can be explained by the effect of the increasing temperature on the ozone chemistry. The chemical ozone destruction is dominated by a catalytic NOx cycle, which is more efficient at higher temperatures. The water vapor enhancement can be explained by transport processes. The rather unusual occurrence of a PSC and a sudden stratospheric warming at midlatitudes suggest that further monitoring of the Earth's middle atmosphere is required for the timely detection of unexpected problems due to ozone loss and climate change.
Abstract. We use Aura/MLS stratospheric water vapour (H2O) measurements as tracer for dynamics and infer interannual variations in the speed of the Brewer–Dobson circulation (BDC) from 2004 to 2011. We correlate one-year time series of H2O in the lower stratosphere at two subsequent pressure levels (68 hPa, ~18.8 km and 56 hPa, ~19.9 km at the Equator) and determine the time lag for best correlation. The same calculation is made on the horizontal on the 100 hPa (~16.6 km) level by correlating the H2O time series at the Equator with the ones at 40° N and 40° S. From these lag coefficients we derive the vertical and horizontal speeds of the BDC in the tropics and extra-tropics, respectively. We observe a clear interannual variability of the vertical and horizontal branch. The variability reflects signatures of the Quasi Biennial Oscillation (QBO). Our measurements confirm the QBO meridional circulation anomalies and show that the speed variations in the two branches of the BDC are out of phase and fairly well anti-correlated. Maximum ascent rates are found during the QBO easterly phase. We also find that transport of H2O towards the Northern Hemisphere (NH) is on the average two times faster than to the Southern Hemisphere (SH) with a mean speed of 1.15 m s−1 at 100 hPa. Furthermore, the speed towards the NH shows much more interannual variability with an amplitude of about 21% whilst the speed towards the SH varies by only 10%. An amplitude of 21% is also observed in the variability of the ascent rate at the Equator which is on the average 0.2 mm s−1.
The efficacy of all major insecticide classes continues to be eroded by the development of resistance mediated, in part, by selection of alleles encoding insecticide insensitive target proteins. The discovery of new insecticide classes acting at novel protein binding sites is therefore important for the continued protection of the food supply from insect predators, and of human and animal health from insect borne disease. Here we describe a novel class of insecticides (Spiroindolines) encompassing molecules that combine excellent activity against major agricultural pest species with low mammalian toxicity. We confidently assign the vesicular acetylcholine transporter as the molecular target of Spiroindolines through the combination of molecular genetics in model organisms with a pharmacological approach in insect tissues. The vesicular acetylcholine transporter can now be added to the list of validated insecticide targets in the acetylcholine signalling pathway and we anticipate that this will lead to the discovery of novel molecules useful in sustaining agriculture. In addition to their potential as insecticides and nematocides, Spiroindolines represent the only other class of chemical ligands for the vesicular acetylcholine transporter since those based on the discovery of vesamicol over 40 years ago, and as such, have potential to provide more selective tools for PET imaging in the diagnosis of neurodegenerative disease. They also provide novel biochemical tools for studies of the function of this protein family.
Clutathione S-transferases (CSTs) with additional activities as fatty acid hydroperoxidases were investigated in soybean (Glycine max 1.) hypocotyls. Aside from the GSTs present in total soluble tissue extracts, enzyme activities and distinct immunoreactive GST polypeptides were also detected in the intercellular washing fluid. Whereas the intracellular isoenzymes were both constitutive and inducible, apoplastic CST and glutathione peroxidase was detectable only in tissues treated with the known GST inducer 2,3,5-triiodobenzoic acid. Monensin inhibited the induced accumulation of apoplastic CST but did not affect the intracellular isoforms. The discovery of apoplastic inducible CST will be discussed in light of the putative function of these enzymes in plants.The GSTs (EC 2.5.1.18) are a family of proteins with severa1 activities (Wilce and Parker, 1994;Marrs, 1996). GSTs catalyze the nucleophilic attack of the thiol of GSH to electrophilic substrates, typically resulting in the formation of GSH conjugates. GSTs are usually dimeric proteins with subunit molecular masses of 24 to 30 kD; they are organized in gene families that produce multiple isoenzymes in eukaryotic organisms. GSTs are mostly soluble cytoplasmic enzymes, but microsomal isoforms are also known in both plants and animals. GSTs conjugate GSH to various xenobiotics, e.g. drugs and pesticides, which is often a key step in their metabolic detoxification and elimination from the cytoplasm (Lamoureux and Rusness, 1989;Kreuz et al., 1996;Reinemer et al., 1996).The multitude of GST isoenzymes in plants and their inducibility by diverse biotic and abiotic factors has been the primary focus of research in recent years. Yet, knowledge about the physiological substrate(s) and function(s) of plant GSTs is only slowly beginning to emerge. Thus, GSTs have been implicated in the conjugation of cinnamic acid and of anthocyanins and in the binding of IAA (Edwards and Dixon, 1991;Marrs, 1996). Some GST isoenzymes display additional activities; for example, the selenium-independent GSH peroxidases catalyze the reduction of fatty acid hydroperoxides with concomitant formation of GSSG (Bartling et al., 1993). Such hydroperoxides are formed by the action of active oxygen species that are generated both as normal by-products of aerobic metabolism and as the result of pathogen infection or exposure to certain abiotic * Corresponding author; e-mail klaus-eugen.kreuz@chbs.mhs. ciba.com; fax 41-61-697-8455.agents. Organic hydroperoxides are potentially cytotoxic, and their removal by GSH peroxidase activity has thus been implicated in the protection of tissues against oxidative stress (Ketterer et al., 1990).In this report we describe the isolation and characterization of GSTs from soybean (Glycine max L.) that display high GSH peroxidase activity toward hydroperoxides of linolenic acid and arachidonic acid. In addition to the soluble intracellular isoenzymes, GST and GSH peroxidase were also found in the intercellular washing fluid of hypocotyls. These apoplastic enzyme ac...
Abstract. Water vapor in the tropical tropopause layer (TTL) has a local radiative cooling effect. As a source for ice in cirrus clouds, however, it can also indirectly produce infrared heating. Using NASA A-Train satellite measurements of CALIPSO and Aura/MLS we calculated the correlation of water vapor, ice water content and temperature in the TTL. We find that temperature strongly controls water vapor (correlation r = 0.94) and cirrus clouds at 100 hPa (r = −0.91). Moreover we observe that the cirrus seasonal cycle is highly (r = −0.9) anticorrelated with the water vapor variation in the TTL, showing higher cloud occurrence during December-January-February. We further investigate the anticorrelation on a regional scale and find that the strong anticorrelation occurs generally in the ITCZ (Intertropical Convergence Zone). The seasonal cycle of the cirrus ice water content is also highly anticorrelated to water vapor (r = −0.91) and our results support the hypothesis that the total water at 100 hPa is roughly constant. Temperature acts as a main regulator for balancing the partition between water vapor and cirrus clouds. Thus, to a large extent, the depleting water vapor in the TTL during DJF is a manifestation of cirrus formation.
BackgroundThe need for documentation in cartilage defects is as obvious as in other medical specialties. Cartilage defects can cause significant pain, and lead to reduced quality of life and loss of function of the affected joint. The risk of developing osteoarthritis is high. Therefore, the socioeconomic burden of cartilage defects should not be underestimated.ObjectiveThe objective of our study was to implement and maintain a registry of all patients undergoing surgical treatment of cartilage defects.MethodsWe designed this multicenter registry for adults whose cartilage defects of a knee, ankle, or hip joint are treated surgically. The registry consists of two parts: one for the physician and one for the patient. Data for both parts will be gathered at baseline and at 6-, 12-, 24-, 36-, 60-, and 120-month follow-ups.ResultsTo date, a wide range of German, Swiss, and Austrian trial sites are taking part in the German Cartilage Registry, soon to be followed by further sites. More than 2124 (as of January 31, 2016) cases are already documented and the first publications have been released.ConclusionsThe German Cartilage Registry addresses fundamental issues regarding the current medical care situation of patients with cartilage defects of knee, ankle, and hip joints. In addition, the registry will help to identify various procedure-specific complications, along with putative advantages and disadvantages of different chondrocyte products. It provides an expanding large-scale, unselected, standardized database for cost and care research for further retrospective studies.Trial RegistrationGerman Clinical Trials Register: DRKS00005617; https://drks-neu.uniklinik-freiburg.de/ drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00005617 (Archived by WebCite at http://www.webcitation.org/6hbFqSws0)
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