High-Frequency (> 100 GHz) and High-Speed (< 1 ps) Electronic Devices

Contains reports on six research projects and a list of publications.MIT Research Laboratory of Electronics Postdoctoral FellowshipNational Science Foundation Grant DMR 90-22933MIT Lincoln Laboratory Advanced Concept ProgramAdvanced Research Projects Agency Contract MDA972-90-C-0021MIT Lincoln LaboratoryNational Aeronautics and Space Administration Grant NAG2-693U.S. Army Research Office Grant DAAL03-92-G-025

Abrupt reversal in emissions and atmospheric abundance of HCFC-133a (CF3CH2Cl)

Hydrochlorofluorocarbon HCFC-133a (CF3CH2Cl) is an anthropogenic compound whose consumption for emissive use is restricted under the Montreal Protocol. A recent study showed rapidly increasing atmospheric abundances and emissions. We report that, following this rise, the at- mospheric abundance and emissions have declined sharply in the past three years. We find a Northern Hemisphere HCFC-133a increase from 0.13 ppt (dry air mole fraction in parts-per-trillion) in 2000 to 0.50 ppt in 2012–mid-2013 followed by an abrupt reversal to 0.44 ppt by early 2015. Global emissions derived from these observations peaked at 3.1 kt in 2011, followed by a rapid decline of 0.5 kt yr−2 to 1.5 kt yr−1 in 2014. Sporadic HCFC-133a pollution events are detected in Europe from our high-resolution HCFC-133a records at three European stations, and in Asia from sam- ples collected in Taiwan. European emissions are estimated to be <0.1 kt yr−1 although emission hotspots were identi- fied in France

High-Frequency (> 100 GHz) and High-Speed (< 10 ps) Electronic Devices

Contains an introduction, reports on four research projects and a list of publications.Defense Advanced Research Projects Agency Contract MDA972-90-C-0021National Aeronautics and Space Administration Grant NAGW-4691National Aeronautics and Space Administration Grant 959705National Science Foundation Grant AST 94-23608National Science Foundation/MRSEC Grant DMR 94-00334MIT Lincoln Laboratory Advanced Concept Program Grant BX-5464U.S. Army Research Office Grant DAAH04-95-1-0610Hertz Foundation FellowshipU.S. Army - Office of Scientific Research Grant DAAH04-94-G-016

Weak Spatial and Temporal Population Genetic Structure in the Rosy Apple Aphid, Dysaphis plantaginea, in French Apple Orchards

We used eight microsatellite loci and a set of 20 aphid samples to investigate the spatial and temporal genetic structure of rosy apple aphid populations from 13 apple orchards situated in four different regions in France. Genetic variability was very similar between orchard populations and between winged populations collected before sexual reproduction in the fall and populations collected from colonies in the spring. A very small proportion of individuals (∼2%) had identical multilocus genotypes. Genetic differentiation between orchards was low (FST<0.026), with significant differentiation observed only between orchards from different regions, but no isolation by distance was detected. These results are consistent with high levels of genetic mixing in holocyclic Dysaphis plantaginae populations (host alternation through migration and sexual reproduction). These findings concerning the adaptation of the rosy apple aphid have potential consequences for pest management

High-Frequency (>100 GHz) and High-Speed (<1 ps) Electronic Devices

Contains an introduction, reports on three research projects and a list of publications.Advanced Research Projects Agency Contract MDA972-90-C-0021National Aeronautics and Space Administration Grant NAG2-693National Aeronautics and Space Administration Contract 959705National Science Foundation/MRSEC Grant DMR 94-00334MIT Lincoln Laboratory Advanced Concept Program Contract BX-5464MIT Research Laboratory of Electronics Postdoctoral FellowshipRome Air Force Laboratory Graduate FellowshipU.S. Army Research Office Grant DAAL03-92-G-0251Hertz Foundation FellowshipU.S. Army Research Office/ASSERT Grant DAAH04-94-G-016

Impaired cardiac contractile function in arginine:glycine amidinotransferase knockout mice devoid of creatine is rescued by homoarginine but not creatine

Aims: Creatine buffers cellular adenosine triphosphate (ATP) via the creatine kinase reaction. Creatine levels are reduced in heart failure, but their contribution to pathophysiology is unclear. Arginine:glycine amidinotransferase (AGAT) in the kidney catalyses both the first step in creatine biosynthesis as well as homoarginine (HA) synthesis. AGAT-/- mice fed a creatine-free diet have a whole body creatine-deficiency. We hypothesized that AGAT-/- mice would develop cardiac dysfunction and rescue by dietary creatine would imply causality. Methods and results: Withdrawal of dietary creatine in AGAT-/- mice provided an estimate of myocardial creatine efflux of ∼2.7%/day; however, in vivo cardiac function was maintained despite low levels of myocardial creatine. Using AGAT-/- mice naïve to dietary creatine we confirmed absence of phosphocreatine in the heart, but crucially, ATP levels were unchanged. Potential compensatory adaptations were absent, AMPK was not activated and respiration in isolated mitochondria was normal. AGAT-/- mice had rescuable changes in body water and organ weights suggesting a role for creatine as a compatible osmolyte. Creatine-naïve AGAT-/- mice had haemodynamic impairment with low LV systolic pressure and reduced inotropy, lusitropy, and contractile reserve. Creatine supplementation only corrected systolic pressure despite normalization of myocardial creatine. AGAT-/- mice had low plasma HA and supplementation completely rescued all other haemodynamic parameters. Contractile dysfunction in AGAT-/- was confirmed in Langendorff perfused hearts and in creatine-replete isolated cardiomyocytes, indicating that HA is necessary for normal cardiac function. Conclusions: Our findings argue against low myocardial creatine per se as a major contributor to cardiac dysfunction. Conversely, we show that HA deficiency can impair cardiac function, which may explain why low HA is an independent risk factor for multiple cardiovascular diseases

Patient Adherence to Tuberculosis Treatment: A Systematic Review of Qualitative Research

From a systematic review of qualitative research, Munro and coauthors found that a range of interacting factors can lead to patients deciding not to complete their course of tuberculosis treatment

Genome wide association study of Preserved Ratio Impaired Spirometry (PRISm)

Background: Preserved Ratio Impaired Spirometry (PRISm) is defined as FEV1 &lt;80% predicted, FEV1/FVC ≥0.70. PRISm is associated with respiratory symptoms and co-morbidities. Our objective was to discover novel genetic signals for PRISm and see if they provide insight into the pathogenesis of PRISm and associated co-morbidities.Methods: We undertook a genome-wide association study (GWAS) of PRISm in UK Biobank participants (Stage 1), and selected SNPs reaching genome-wide significance for replication in 13 cohorts (Stage 2). A combined meta-analysis of Stage 1 and Stage 2 was done to determine top SNPs. We used cross-trait Linkage Disequilibrium score regression to estimate genome-wide genetic correlation between PRISM and pulmonary and extra-pulmonary traits. Phenome-wide association studies of top SNPs was performed. Results: 22 signals reached significance in the joint meta-analysis, including four signals novel for lung function. A strong genome-wide genetic correlation (rg) between PRISm and spirometric COPD (rg = 0.62, p-value &lt;0.001) was observed, and genetic correlation with type II diabetes (rg = 0.12, p-value 0.007). PheWAS showed that 18 of 22 signals were associated with diabetic traits and 7 with blood pressure traits.Discussion: This is the first GWAS to successfully identify SNPs associated with PRISm. Four of the signals; rs7652391 (nearest gene MECOM), rs9431040 (HLX), rs62018863 (TMEM114) and rs185937162 (HLA-B) have not been described in association with lung function before, demonstrating the utility of using different lung function phenotypes in GWAS. Genetic factors associated with PRISm are strongly correlated with risk of both other lung diseases and extra-pulmonary co-morbidity.<br/

Nuclear astrophysics with radioactive ions at FAIR

The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process, β-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes