We give a brief survey of thermodynamic metrics, in particular the Hessian of the entropy function, and how they apply to black hole thermodynamics. We then provide a detailed discussion of the Gibbs ...surface of Kerr black holes. In particular, we analyze its global properties and extend it to take the entropy of the inner horizon into account. A brief discussion of Kerr-Newman black holes is included.
We study thermodynamic geometries of Myers–Perry (MP) black holes with arbitrary number of angular momenta. This geometric method allows us to visualize thermodynamic state spaces of the MP black ...holes as wedges embedded in a Minkowski-like parameter space. The opening angles of these wedges are uniquely determined by the number of spacetime dimensions
d
, and the number of angular momenta associated with the MP black holes,
n
. The geometric structure captures extremal limits of the MP black holes, and hence serves as a method for identifying the black hole’s extremal limit. We propose that classification of the MP black hole solutions should based on these uncovered structures. In order for the ultraspinning regime to exist, at least one of the angular momenta has to be set to zero. Finally, we conjecture that the membrane phase of ultraspinning MP black holes is reached at the minimum temperature in the case where 2
n
<
d
−3 based on the thermodynamic curvature obtained.
It is unclear whether the demands of good metabolic control or the consequences of poor control have a greater influence on quality of life (QOL) for adolescents with diabetes. This study aimed to ...assess these relations in a large international cohort of adolescents with diabetes and their families.
The study involved 2,101 adolescents, aged 10-18 years, from 21 centers in 17 countries in Europe, Japan, and North America. Clinical and demographic data were collected from March through August 1998. HbA(1c) was analyzed centrally (normal range 4.4-6.3%; mean 5.4%). Adolescent QOL was assessed by a previously developed Diabetes Quality of Life (DQOL) questionnaire for adolescents, measuring the impact of diabetes, worries about diabetes, satisfaction with life, and health perception. Parents and health professionals assessed family burden using newly constructed questionnaires.
Mean HbA(1c) was 8.7% (range 4.8-17.4). Lower HbA(1c) was associated with lower impact (P < 0.0001), fewer worries (P < 0.05), greater satisfaction (P < 0.0001), and better health perception (P < 0.0001) for adolescents. Girls showed increased worries (P < 0.01), less satisfaction, and poorer health perception (P < 0.01) earlier than boys. Parent and health professional perceptions of burden decreased with age of adolescent (P < 0.0001). Patients from ethnic minorities had poorer scores for impact (P < 0.0001), worries (P < 0.05), and health perception (P < 0.01). There was no correlation between adolescent and parent or between adolescent and professional scores.
In a multiple regression model, lower HbA(1c) was significantly associated with better adolescent-rated QOL on all four subscales and with lower perceived family burden as assessed by parents and health professionals.
Twenty-one international pediatric diabetes centers from 17 countries investigated the effect of simple feedback about the grand mean HbA(1c) level of all centers and the average value of each center ...on changes in metabolic control, rate of severe hypoglycemia, and insulin therapy over a 3-year period.
Clinical data collection and determination of HbA(1c) levels were conducted at a central location in 1995 (n = 2,780, age 0-18 years) and 1998 (n = 2,101, age 11-18 years).
Striking differences in average HbA(1c) concentrations were found among centers; these differences remained after adjustment for the significant confounders of sex, age, and diabetes duration. They were apparent even in patients with short diabetes duration and remained stable 3 years later (mean adjusted HbA(1c) level: 8.62 +/- 0.03 vs. 8.67 +/- 0.04 1995 vs. 1998, respectively). Three centers had improved significantly, four centers had deteriorated significantly in their overall adjusted HbA(1c) levels, and 14 centers had not changed in glycemic control. During the observation period, there were increases in the adjusted insulin dose by 0.076 U/kg, the adjusted number of injections by 0.23 injections per day, and the adjusted BMI by 0.95 kg/m(2). The 1995 versus 1998 difference in glycemic control for the seven centers could not be explained by prevailing insulin regimens or rates of hypoglycemia.
This study reveals significant outcome differences among large international pediatric diabetes centers. Feedback and comparison of HbA(1c) levels led to an intensification of insulin therapy in most centers, but improved glycemic control in only a few.
We find all Ricci semi-symmetric as well as all conformally semi-symmetric spacetimes. Neither of these properties implies the other. However, we find that for spacetimes (3+1 dim) with nonzero Weyl ...tensor and nonzero tracefree part of the Ricci tensor conformal semi-symmetry and Ricci semi-symmetry is equivalent.
The Hessian of either the entropy or the energy function can be regarded as a metric on a Gibbs surface. For two parameter families of asymptotically flat black holes in arbitrary dimension one or ...the other of these metrics are flat, and the state space is a flat wedge. The mathematical reason for this is traced back to the scale invariance of the Einstein-Maxwell equations. The picture of state space that we obtain makes some properties such as the occurence of divergent specific heats transparent.
The 65-kD isoform of glutamic acid decarboxylase (GAD) is a major autoantigen in patients with type 1 diabetes mellitus. This trial assessed the ability of alum-formulated GAD (GAD-alum) to reverse ...recent-onset type 1 diabetes in patients 10 to 18 years of age.
We randomly assigned 70 patients with type 1 diabetes who had fasting C-peptide levels above 0.1 nmol per liter (0.3 ng per milliliter) and GAD autoantibodies, recruited within 18 months after receiving the diagnosis of diabetes, to receive subcutaneous injections of 20 microg of GAD-alum (35 patients) or placebo (alum alone, 35 patients) on study days 1 and 30. At day 1 and months 3, 9, 15, 21, and 30, patients underwent a mixed-meal tolerance test to stimulate residual insulin secretion (measured as the C-peptide level). The effect of GAD-alum on the immune system was also studied.
Insulin secretion gradually decreased in both study groups. The study treatment had no significant effect on change in fasting C-peptide level after 15 months (the primary end point). Fasting C-peptide levels declined from baseline levels significantly less over 30 months in the GAD-alum group than in the placebo group (-0.21 vs. -0.27 nmol per liter -0.62 vs. -0.81 ng per milliliter, P=0.045), as did stimulated secretion measured as the area under the curve (-0.72 vs. -1.02 nmol per liter per 2 hours -2.20 vs. -3.08 ng per milliliter per 2 hours, P=0.04). No protective effect was seen in patients treated 6 months or more after receiving the diagnosis. Adverse events appeared to be mild and similar in frequency between the two groups. The GAD-alum treatment induced a GAD-specific immune response.
GAD-alum may contribute to the preservation of residual insulin secretion in patients with recent-onset type 1 diabetes, although it did not change the insulin requirement. (ClinicalTrials.gov number, NCT00435981.)
OBJECTIVE: To find a simple definition of partial remission in type 1 diabetes that reflects both residual β-cell function and efficacy of insulin treatment. RESEARCH DESIGN AND METHODS: A total of ...275 patients aged <16 years were followed from onset of type 1 diabetes. After 1, 6, and 12 months, stimulated C-peptide during a challenge was used as a measure of residual β-cell function. RESULTS: By multiple regression analysis, a negative association between stimulated C-peptide and A1C (regression coefficient -0.21, P < 0.001) and insulin dose (-0.94, P < 0.001) was shown. These results suggested the definition of an insulin dose-adjusted A1C (IDAA1C) as A1C (percent) + 4 x insulin dose (units per kilogram per 24 h). A calculated IDAA1C less-than or equal to9 corresponding to a predicted stimulated C-peptide >300 pmol/l was used to define partial remission. The IDAA1C less-than or equal to9 had a significantly higher agreement (P < 0.001) with residual β-cell function than use of a definition of A1C less-than or equal to7.5%. Between 6 and 12 months after diagnosis, for IDAA1C less-than or equal to9 only 1 patient entered partial remission and 61 patients ended partial remission, for A1C less-than or equal to7.5% 15 patients entered partial remission and 53 ended, for a definition of insulin dose less-than or equal to0.5 units · kg⁻¹ · 24 h⁻¹ 5 patients entered partial remission and 66 ended, and for stimulated C-peptide (>300 pmol/l) 9 patients entered partial remission and 49 ended. IDAA1C at 6 months has good predictive power for stimulated C-peptide concentrations after both 6 and 12 months. CONCLUSIONS: A new definition of partial remission is proposed, including both glycemic control and insulin dose. It reflects residual β-cell function and has better stability compared with the conventional definitions.
We use a contact geometric method to study Myers-Perry (MP) black holes in arbitrary dimensions with arbitrary angular momenta. We have shown that the MP black holes of dimension d with n equal ...nonzero spins and 2n ≥ d − 3 all have extremal limits as expected and that we should classify MP black holes in three series depending on whether the value of 2n − d + 3 is 0, 1 or 2. For black holes with 2n < d − 3 the Ruppeiner curvature diverges although they have no extremal limits. In order to have an ultraspinning mode at least one spin of the MP black hole must be set to zero. Our result agrees with others in the literature where the authors are able to establish the minimum temperature surface on which the membrane phase of ultraspinning MP black holes occurs. We conjecture that the membrane phase of ultraspinning MP black holes is reached around the minimum temperature in the case 2n < d − 3 which is where the Ruppeiner curvature diverges.
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