Serum angiotensin-converting enzyme (ACE) was measured in 150 insulin-dependent diabetes mellitus (IDDM) patients and 72 healthy subjects by radioassay, using 3H-hippuryl-glycyl-glycine as a ...substrate. Mean (SD) serum ACE activity in diabetic patients was 120 +/- 33 nmol ml-1 min-1 (range 46-215) and was significantly increased by 56% compared to control values (77 +/- 23 nmol ml-1 min-1, range 46-125, P < 0.001). ACE activity > 125 nmol ml-1 min-1 was observed in 60 of 150 IDDM patients. 96 IDDM patients were normoalbuminuric (< 22 mg 24 h-1) and 49 patients were micro- or macroalbuminuric (range 22-6010 mg 24 h-1). Micro- and macroalbuminuric IDDM patients were found to have significantly greater ACE activity values than normoalbuminuric patients (128 +/- 36 vs. 115 +/- 30 nmol ml-1 min-1, P = 0.025). Metabolically well-controlled IDDM patients (glycosylated haemoglobin < or = 8%) had lower ACE activity values than the patients with glycosylated haemoglobin greater than 8% (109 +/- 20 vs. 127 +/- 32 nmol ml-1 min-1, P < 0.02). A significant correlation between degree of metabolic control and ACE activity was found (r = 0.435, P < 0.001) so that an increase in one glycosylated quartile unit is accompanied by an increase in ACE activity of 10.5 nmol ml-1 min-1. Thus ACE activity in the serum of IDDM patients was increased by 56% in 40% of the patients. It was increased in IDDM patients without complications and in patients with retinopathy or nephropathy.
Some comments are made on the attempt in a recent meteorological forecasting experiment (Chong, Testud and Roux, 1983) to develop an algorithm for correcting the effects of advection in dual-Doppler ...radar observations made in the COPLAN mode. It is shown that the advection correction algorithm in question is mathematically exact only if temporal errors are due exclusively to advection. In the case where both intrinsic evolution and advection are present, a different solution is found. The advection correction algorithm is found to worsen evolution errors, and an explicit evaluation of the exacerbating factor is provided.
The time dependent energy balance climate model of Schneider and Gal-Chen (1973) is extended to consider the relative importance of radiative and dynamic parameterizations on the sensitivity of the ...model's equilibrium climate to perturbations in solar input. The albedo-temperature feedback parameterization of Sellers (1969) is used to test the sensitivity of the model's global temperature and equator-to-pole temperature gradient to solar input changes with six different dynamical parameterizations. The nonlinear eddy flux parameterization used by Stone (1973) appears to give the best results, but the assumption that global average static stability remains constant during climatic changes (on earth) is not supported by our experiments; but also cannot be ruled out as a possibility. The thermodynamic processes of ice-albedo-temperature feedback and moist adiabatic convective adjustment are found to dominate the effects of large-scale eddies in controlling the behavior of the globally-averaged lapse rate during climatic changes. This conclusion is drawn after comparisons of our results with those computed by Wetherald and Manabe with a three-dimensional general circulation model. Our findings suggest that thermodynamic processes must be central elements of any climatic theory, and that interpretation of the results of complex general circulation models can be made easier by drawing on the experience gained with simpler models like the energy balance varieties used here.
Abstract
We present analysis of the light curves (LCs) of 77 hydrogen-poor superluminous supernovae (SLSNe I) discovered during the Zwicky Transient Facility Phase I operation. We find that the ...majority (67%) of the sample can be fit equally well by both magnetar and ejecta–circumstellar medium (CSM) interaction plus
56
Ni decay models. This implies that LCs alone cannot unambiguously constrain the physical power sources for an SLSN I. However, 23% of the sample show inverted V-shape, steep-declining LCs or features of long rise and fast post-peak decay, which are better described by the CSM+Ni model. The remaining 10% of the sample favors the magnetar model. Moreover, our analysis shows that the LC undulations are quite common, with a fraction of 18%–44% in our gold sample. Among those strongly undulating events, about 62% of them are found to be CSM-favored, implying that the undulations tend to occur in the CSM-favored events. Undulations show a wide range in energy and duration, with median values (and 1
σ
errors) being as
1.7
%
−
0.7
%
+
1.5
%
E
rad
,
total
and
28.8
−
9.1
+
14.4
days, respectively. Our analysis of the undulation timescales suggests that intrinsic temporal variations of the central engine can explain half of the undulating events, while CSM interaction (CSI) can account for the majority of the sample. Finally, all of the well-observed He-rich SLSNe Ib either have strongly undulating LCs or the LCs are much better fit by the CSM+Ni model. These observations imply that their progenitor stars have not had enough time to lose all of the He-envelopes before supernova explosions, and H-poor CSM are likely to present in these events.
