Rapid transcriptional and metabolic regulation of the deacclimation process in cold acclimated Arabidopsis thaliana

Background: During low temperature exposure, temperate plant species increase their freezing tolerance in a process termed cold acclimation. This is accompanied by dampened oscillations of circadian clock genes and disrupted oscillations of output genes and metabolites. During deacclimation in response to warm temperatures, cold acclimated plants lose freezing tolerance and resume growth and development. While considerable effort has been directed toward understanding the molecular and metabolic basis of cold acclimation, much less information is available about the regulation of deacclimation.Results: We report metabolic (gas chromatography-mass spectrometry) and transcriptional (microarrays, quantitative RT-PCR) responses underlying deacclimation during the first 24 h after a shift of Arabidopsis thaliana (Columbia-0) plants cold acclimated at 4 °C back to warm temperature (20 °C). The data reveal a faster response of the transcriptome than of the metabolome and provide evidence for tightly regulated temporal responses at both levels. Metabolically, deacclimation is associated with decreasing contents of sugars, amino acids, glycolytic and TCA cycle intermediates, indicating an increased need for carbon sources and respiratory energy production for the activation of growth. The early phase of deacclimation also involves extensive down-regulation of protein synthesis and changes in the metabolism of lipids and cell wall components. Hormonal regulation appears particularly important during deacclimation, with extensive changes in the expression of genes related to auxin, gibberellin, brassinosteroid, jasmonate and ethylene metabolism. Members of several transcription factor families that control fundamental aspects of morphogenesis and development are significantly regulated during deacclimation, emphasizing that loss of freezing tolerance and growth resumption are transcriptionally highly interrelated processes. Expression patterns of some clock oscillator components resembled those under warm conditions, indicating at least partial re-activation of the circadian clock during deacclimation.Conclusions: This study provides the first combined metabolomic and transcriptomic analysis of the regulation of deacclimation in cold acclimated plants. The data indicate cascades of rapidly regulated genes and metabolites that underlie the developmental switch resulting in reduced freezing tolerance and the resumption of growth. They constitute a large-scale dataset of genes, metabolites and pathways that are crucial during the initial phase of deacclimation. The data will be an important reference for further analyses of this and other important but under-researched stress deacclimation processes

Monte-Carlo simulation studies of the nonlinear imaging of a two dimensional surface wave field by a synthetic aperture radar

The imaging of ocean surface waves by synthetic aperture radar (SAR) is investigated using two-dimensional Monte-Carlo simulations. The properties of the SAR imaging mechanism for windseas and swell in the Bragg scattering regime are discussed as a function of a few governing non-dimensional parameters formed from a combination of SAR and ocean wave parameters. The parameter ranges may be classified into three regimes corresponding to linear and weakly nonlinear, medium nonlinear and strongly nonlinear imaging. The nonlinearities are induced by motion effects (velocity bunching, velocity spread and acceleration smearing), while the real aperture radar (RAR) tilt and hydrodynamic modulation processes are regarded as linear. In the strongly nonlinear imaging regime, the velocity bunching mechanism causes a rotation of the spectral peak towards the range direction and a stretching of the peak wavelength. In addition, the azimuthal resolution is degraded through the Doppler spreading arising from the different facet velocities within a SAR resolution cell. The imaging properties in this regime are largely governed by two non-dimensional parameters, the velocity bunching and velocity smearing parameter. The nonlinear imaging distortions are strongest for broad spectra (windseas) and are significantly weaker for narrow-band swell. In the linear and weakly nonlinear imaging regime, the superposition of the hydrodynamic and tilt cross-section modulation and the velocity bunching transfer function normally produces a rotation of the spectral peak towards the azimuthal direction. The interference characteristics of these different modulation mechanisms depends on the wave propagation direction and can lead to a significant distortion of the image. This is often seen in large differences in the image modulation depths of waves propagating parallel and anti-parallel to the flight direction

Summary of Total Mercury Concentrations in Fillets of Selected Sport Fishes Collected during 2000–2003 from Lake Natoma, Sacramento County, California

This report summarizes results of total mercury measurements in skinless fillets of sport fishes collected during August 2000, September–October 2002, and July 2003 from Lake Natoma, a small (8,760 acre-feet) afterbay for Folsom Dam on the lower American River. The primary objective of the study was to determine if mercury concentrations in fillets approached or exceeded guidelines for human consumption. The Food and Drug Administration (FDA) human-health action level for methylmercury in commercially caught fish is 1.0 μg/g (microgram per gram); the U.S. Environmental Protection Agency (USEPA) human-health criterion for methylmercury residue in fish tissue is 0.30 μg/g. Wet weight concentrations of total mercury in skinless fillets were as high as 0.19 μg/g in bluegill (Lepomis macrochirus), 0.39 μg/g in redear sunfish (L. microlophus), 1.02 μg/g in largemouth bass (Micropterus salmoides), and 1.89 μg/g in channel catfish (Ictalurus punctatus). Maximum concentrations of mercury in other fish species varied from 0.10 μg/g in rainbow trout (Oncorhynchus mykiss) to 0.56 μg/g in white catfish (Ameiurus catus). Altogether, 1 of 86 largemouth bass and 11 of 11 channel catfish exceeded the FDA human-health action level. In addition, 1 of 20 redear sunfish, 26 of 86 largemouth bass, 2 of 3 spotted bass (M. punctulatus), 1 of 1 brown bullhead (A. nebulosus), and 1 of 1 white catfish exceeded the USEPA human-health criterion. These results indicate that some fish species inhabiting Lake Natoma contain undesirably high concentrations of mercury in their skinless fillets

Summary of Total Mercury Concentrations in Fillets of Selected Sport Fishes Collected during 2000–2003 from Lake Natoma, Sacramento County, California

This report summarizes results of total mercury measurements in skinless fillets of sport fishes collected during August 2000, September–October 2002, and July 2003 from Lake Natoma, a small (8,760 acre-feet) afterbay for Folsom Dam on the lower American River. The primary objective of the study was to determine if mercury concentrations in fillets approached or exceeded guidelines for human consumption. The Food and Drug Administration (FDA) human-health action level for methylmercury in commercially caught fish is 1.0 μg/g (microgram per gram); the U.S. Environmental Protection Agency (USEPA) human-health criterion for methylmercury residue in fish tissue is 0.30 μg/g. Wet weight concentrations of total mercury in skinless fillets were as high as 0.19 μg/g in bluegill (Lepomis macrochirus), 0.39 μg/g in redear sunfish (L. microlophus), 1.02 μg/g in largemouth bass (Micropterus salmoides), and 1.89 μg/g in channel catfish (Ictalurus punctatus). Maximum concentrations of mercury in other fish species varied from 0.10 μg/g in rainbow trout (Oncorhynchus mykiss) to 0.56 μg/g in white catfish (Ameiurus catus). Altogether, 1 of 86 largemouth bass and 11 of 11 channel catfish exceeded the FDA human-health action level. In addition, 1 of 20 redear sunfish, 26 of 86 largemouth bass, 2 of 3 spotted bass (M. punctulatus), 1 of 1 brown bullhead (A. nebulosus), and 1 of 1 white catfish exceeded the USEPA human-health criterion. These results indicate that some fish species inhabiting Lake Natoma contain undesirably high concentrations of mercury in their skinless fillets

Theory of synthetic aperture radar ocean imaging: A MARSEN view

This paper reviews basic synthetic aperture radar (SAR) theory of ocean wave imaging mechanisms, using both known work and recent experimental and theoretical results from the Marine Remote Sensing (MARSEN) Experiment. Several viewpoints that have contributed to the field are drawn together in a general analysis of the backscatter statistics of a moving sea surface. A common focus for different scattering models is provided by the mean image impulse response function, which is shown to be identical to the (spatially varying) frequency variance spectrum of the local complex reflectivity coefficient. From the analysis has emerged a more complete view of the SAR imaging phenomenon than has been previously available. A new, generalized imaging model is proposed

Malaria: how useful are clinical criteria for improving the diagnosis in a highly endemic area?

To assess the validity of clinical criteria, we investigated 2096 outpatients diagnosed as malaria cases by nurses at a rural health subcentre in a highly endemic area of Papua New Guinea. 73% of the children < 10 years old had a positive blood slide for any species of Plasmodium and 32% had ⩾ 10 000 P. falciparum parasites per μL. For adults the frequencies were 51% and 9%, respectively. Stepwise logistic regression identified spleen size, no cough, temperature, no chest indrawing, and normal stools as significant predictors for a positive blood slide in children; no cough and normal stools predicted a positive blood slide in adults. Fever, no cough, vomiting, and enlarged spleen were significant predictors for a P. falciparum parasitaemia ⩾ 10 000/μL in children; in adults the only predictor was vomiting. In children the association of no cough and enlarged spleen had the best predictive value for a positive blood slide, and a temperature ⩾ 38 °C had the best predictive value for a P. falciparum parasitaemia ⩾ 10 000 μL. In adults, no major symptom had a good predictive value for a positive blood slide but vomiting had the best predictive value for a P. falciparum parasitaemia ⩾ 10 000/μL. When microscopy is not available, these findings can help in areas of high endemicity to determine which patients with a history of fever are most likely to have malaria and, more importantly, for which patients another diagnosis should be strongly considere

Alcohol Consumption during a Pandemic Lockdown Period and Change in Alcohol Consumption Related to Worries and Pandemic Measures

Whether lockdown related to the COVID-19 pandemic influences alcohol consumption is not well known. This study assesses alcohol consumption and hazardous drinking behavior during the initial phase of pandemic measures in Norway and identifies potential risk factors. A cross-sectional study (N = 25,708) was conducted in Bergen, Norway, following the first six weeks of strict infection control measures. In a model of self-assessed increased alcohol consumption, logistic regression analysis was conducted with independent variables for COVID-19-related worries, joblessness, quarantine, self-reported drinking behavior, age, gender, and occupational situation. These are reported with odds ratios (ORs) with 95% confidence intervals. Fifty-one percent of respondents reported economic or health-related worries due to COVID-19, 16% had been in quarantine, 49% worked/studied from home, 54% reported hazardous drinking behavior, and 13% reported increased alcohol consumption. People aged 30–39 years had elevated odds of increased alcohol consumption during lockdown (OR 3.1, 2.4−3.8) compared to the oldest adults. Increased drinking was more frequent among people reporting economic worries (OR 1.6, 1.4−1.8), those quarantined (OR 1.2, 1.1−1.4), and those studying or working at home (OR 1.4, 1.3−1.6). More than half of respondents reported hazardous drinking behavior. Increased alcohol consumption during lockdown was common among people with economic worries, people in quarantine, and people studying or working at home. These data could be important when adjusting pandemic measures.publishedVersio

COVID-19 Informationsvermeidungsskala (COVIAS)

This scale was developed at the University of Mannheim. It is based on the Information Avoidance Scale by Howell & Shepperd (2016). Several items were adapted and added to make this instrument applicable to the COVID-19 pandemic

Lung cancer induced in mice by the envelope protein of jaagsiekte sheep retrovirus (JSRV) closely resembles lung cancer in sheep infected with JSRV

BACKGROUND: Jaagsiekte sheep retrovirus (JSRV) causes a lethal lung cancer in sheep and goats. Expression of the JSRV envelope (Env) protein in mouse lung, by using a replication-defective adeno-associated virus type 6 (AAV6) vector, induces tumors resembling those seen in sheep. However, the mouse and sheep tumors have not been carefully compared to determine if Env expression alone in mice can account for the disease features observed in sheep, or whether additional aspects of virus replication in sheep are important, such as oncogene activation following retrovirus integration into the host cell genome. RESULTS: We have generated mouse monoclonal antibodies (Mab) against JSRV Env and have used these to study mouse and sheep lung tumor histology. These Mab detect Env expression in tumors in sheep infected with JSRV from around the world with high sensitivity and specificity. Mouse and sheep tumors consisted mainly of well-differentiated adenomatous foci with little histological evidence of anaplasia, but at long times after vector exposure some mouse tumors did have a more malignant appearance typical of adenocarcinoma. In addition to epithelial cell tumors, lungs of three of 29 sheep examined contained fibroblastic cell masses that expressed Env and appeared to be separate neoplasms. The Mab also stained nasal adenocarcinoma tissue from one United States sheep, which we show was due to expression of Env from ovine enzootic nasal tumor virus (ENTV), a virus closely related to JSRV. Systemic administration of the AAV6 vector encoding JSRV Env to mice produced numerous hepatocellular tumors, and some hemangiomas and hemangiosarcomas, showing that the Env protein can induce tumors in multiple cell types. CONCLUSION: Lung cancers induced by JSRV infection in sheep and by JSRV Env expression in mice have similar histologic features and are primarily characterized by adenomatous proliferation of peripheral lung epithelial cells. Thus it is unnecessary to invoke a role for insertional mutagenesis, gene activation, viral replication, or expression of other viral gene products in sheep lung tumorigenesis, although these processes may play a role in other clinically less important sequelae of JSRV infection such as metastasis observed with variable frequency in sheep