Impact of the electron density and temperature gradient on drift-wave turbulence in the Large Plasma Device

In this paper we present an experimental study of edge turbulence in the Large Plasma Device at UCLA. We utilize a scan of discharge power and prefill pressure (neutral density) to show experimentally that turbulent density fluctuations decrease with decreasing density gradient, as predicted for resistive drift-wave turbulence (RDWT). As expected for RDWT, we observe that the cross-phase between the density and potential fluctuations is close to 0. Moreover, the addition of an electron temperature gradient leads to a reduction in the amplitude of the density fluctuations, as expected for RDWT. However, counter to theoretical expectations, we find that the potential fluctuations do not follow the same trends as the density fluctuations for changes either in density gradients or the addition of a temperature gradient. The disconnect between the density and potential fluctuations is connected to changes in the parallel flows as a result of differences in the prefill pressure, i.e. neutral density. Further analysis of the density and potential fluctuation spectra show that the electron temperature gradient reduces the low frequency fluctuations up to 10kHz role= presentation style= box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: normal; vertical-align: baseline; display: inline; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; position: relative; \u3e10kHz10kHzand the introduction of a temperature gradient leads to an unexpected ∼π role= presentation style= box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: normal; vertical-align: baseline; display: inline; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; position: relative; \u3e∼∼πshift of the density–potential cross-phase at ∼10kHz role= presentation style= box-sizing: border-box; margin: 0px; padding: 0px; border: 0px; font-family: inherit; font-variant-caps: inherit; font-stretch: inherit; line-height: normal; vertical-align: baseline; display: inline; word-spacing: normal; word-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; position: relative; \u3e∼10kHz∼10kHz, while maintaining the typical resistive drift-wave cross-phase at lower frequencies. These experiments partly confirm existing knowledge on resistive drift-wave turbulence, but also introduce new observations that indicate a need for dedicated nonlinear three-dimensional turbulence simulations that include neutrals

Chlorophyll fluorescence characteristics, performance and survival of freshly lifted and cold stored Douglas fir seedlings

The physiological condition of three-year-old Douglas fir [Pseudotsuga menziesii (Mirb.) Franco] was periodically assessed from October to May 1998/1999 during propagation of seedlings in an Irish nursery. Seedling physiological status was evaluated in situ using determinations of chlorophyll fluorescence and plant water status. Pre- and post-cold stored (either -2 oC or $+$0.5 oC) plant vitality was examined using determinations of root growth potential (RGP), root electrolyte leakage (REL), shoot water content and chlorophyll fluorescence. Data obtained from freshly lifted and cold stored stock showed that chlorophyll fluorescence provides a reliable (non-destructive) method of evaluating a seedlings potential field performance in both pre-lift (direct planting) and post-storage (outplanting) situations. Variations in survival and an index of plant health were paralleled by inverse changes in the effective quantum yield of photosystem II ($\Phi$ PSII) from November to April. Significant positive non-linear relationships were found between RGP and $\Phi$ PSII, though they were of limited predictive ability in terms of outplanting performance. Post-storage fluorescence assessments indicated down-regulation and/or damage of the plants photosynthetic light-harvesting complex, which depended on storage temperature and duration.Caractéristiques de la fluorescence chlorophyllienne, performances et survie de plants de Douglas vert récemment arrachés et stockés au froid. La condition physiologique Douglas [Pseudotsuga menziesii (Mirb.) Franco] âgés de trois ans a été évaluée périodiquement de octobre à mai 1998/1999 pendant la dans une pépinière irlandaise. Le statut physiologique des semis a été évalué in situ par la détermination de la fluorescence chlorophyllienne et de l'état hydrique des plants. La viabilité des plants avant et après stockage au froid (-2 oC ou $+$0,5 oC) fut examinée par la détermination du potentiel de croissance racinaire (RGP), du relargage d'électrolytes par les racines (REL), de l'humidité des bourgeons et de la fluorescence chlorophyllienne. Les données obtenues sur des plants récemment arrachés et conservés au froid montrent que la mesure de la fluorescence chlorophyllienne est une méthode fiable (non destructive) pour évaluer la performance potentielle au champ des germinations dans les situations de plants avant levage (plantation directe) et de plants stockée. Les variations de survie et index de vitalité du plant étaient inversement proportionnelles aux variations du rendement effectif du photosystème II ($\Phi$ PSII) de novembre à avril. Des relations positives significatives non-linéaires entre RGP et $\Phi$ PSII furent trouvées, bien qu'elles aient une capacité limitée à prédire la performance des plants transplantés. Après stockage, les mesures de fluorescence montrèrent l'inhibition et/ou la détérioration de l'efficacité photochimique du photosystème II qui dépendait de la température et de la durée du stockage

Empagliflozin in Patients with Chronic Kidney Disease

Background The effects of empagliflozin in patients with chronic kidney disease who are at risk for disease progression are not well understood. The EMPA-KIDNEY trial was designed to assess the effects of treatment with empagliflozin in a broad range of such patients. Methods We enrolled patients with chronic kidney disease who had an estimated glomerular filtration rate (eGFR) of at least 20 but less than 45 ml per minute per 1.73 m(2) of body-surface area, or who had an eGFR of at least 45 but less than 90 ml per minute per 1.73 m(2) with a urinary albumin-to-creatinine ratio (with albumin measured in milligrams and creatinine measured in grams) of at least 200. Patients were randomly assigned to receive empagliflozin (10 mg once daily) or matching placebo. The primary outcome was a composite of progression of kidney disease (defined as end-stage kidney disease, a sustained decrease in eGFR to < 10 ml per minute per 1.73 m(2), a sustained decrease in eGFR of & GE;40% from baseline, or death from renal causes) or death from cardiovascular causes. Results A total of 6609 patients underwent randomization. During a median of 2.0 years of follow-up, progression of kidney disease or death from cardiovascular causes occurred in 432 of 3304 patients (13.1%) in the empagliflozin group and in 558 of 3305 patients (16.9%) in the placebo group (hazard ratio, 0.72; 95% confidence interval [CI], 0.64 to 0.82; P < 0.001). Results were consistent among patients with or without diabetes and across subgroups defined according to eGFR ranges. The rate of hospitalization from any cause was lower in the empagliflozin group than in the placebo group (hazard ratio, 0.86; 95% CI, 0.78 to 0.95; P=0.003), but there were no significant between-group differences with respect to the composite outcome of hospitalization for heart failure or death from cardiovascular causes (which occurred in 4.0% in the empagliflozin group and 4.6% in the placebo group) or death from any cause (in 4.5% and 5.1%, respectively). The rates of serious adverse events were similar in the two groups. Conclusions Among a wide range of patients with chronic kidney disease who were at risk for disease progression, empagliflozin therapy led to a lower risk of progression of kidney disease or death from cardiovascular causes than placebo