Abstract.This paper describes a technique for comparing numerical methods that have been designed to solve stiff systems of ordinary differential equations. The basis of a fair comparison is discussed in detail. Measurements of cost and reliability are made over a collection of 25 carefully selected problems. The problems have been designed to show how certain major factors affect the performance of a method.The technique is applied to five methods, of which three turn out to be quite good, including one based on backward differentiation formulas, another on second derivative formulas, aaud a third on extrapolation. However, each of the three has a weakness of its own, which can be identified with particular problem characteristics.

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Objective. This study was undertaken to investigate the prevalence of celiac disease in children and adolescents with Down syndrome.Material and Methods. Forty-three children and adolescents with Down syndrome were screened for IgAantigliadin antibodies (AGA) and IgA-antiendomysium antibodies (EMA). Patients found to be either AGA-or EMA-positive were investigated further with intestinal biopsy.Results. None of the 43 patients had known celiac disease at entry into the study; 37% (16/43) were found to have AGA levels above normal, and 16% (7/43) to be EMA-positive. Of the 15 patients who underwent biopsy, 8 manifested villous atrophy. Villous atrophy was present in all 7 of the EMA-positive patients, whereas the villi were normal in 7 of the 13 AGA-positive patients who underwent biopsy.Conclusions. EMA is a good immunologic marker for use in screening for celiac disease, and screening is justified in patients with Down syndrome. Pediatrics 1998; 101:272-275; Down syndrome, celiac disease, IgA-antigliadin antibodies, IgA-antiendomysium antibodies.

Using the nationwide childhood-onset diabetes register in Sweden, we were able to trace children who contracted diabetes before the age of 15 years and who were born at a specific hospital in Sweden where maternal sera from delivery had been stored during the years 1969-1989. Sera obtained at delivery from 57 mothers of diabetic children were compared with sera from 203 mothers of control subjects who were delivered at the same hospital during the same time period. The sera were analyzed blindly using a group-specific enzyme-linked immunosorbent assay for enteroviral IgG and IgM antibodies before and after urea wash as an avidity test. On the same plates, IgG antibodies to herpes, mumps, and toxoplasmosis were analyzed. The mean absorbance values of enteroviral IgG antibodies against enteroviral antigens (echo30, coxsackie B5, and echo9) were significantly higher among mothers whose children later developed diabetes (P = 0.002, P = 0.02, and P = 0.04, respectively). When reduction in activity after urea wash, indicating recently formed antibodies, was compared, the differences were even more pronounced (P < 0.001 for all three antigens). No significant differences were found for antibodies against herpes (all types), herpes type 2, mumps, or toxoplasmosis. When IgM activity and/or a significant decrease in avidity index, an indication of recent enterovirus infection, was used as a risk exposure, the odds ratio standardized for year of birth (95% confidence interval) was 3.19 (1.39-7.30). We conclude that the results of this study indicate that enteroviral infection during pregnancy is a risk factor for childhood-onset diabetes in the offspring.(ABSTRACT TRUNCATED AT 250 WORDS)

Type I (insulin-dependent) diabetes mellitus is a multifactorial disease that develops after exposure to unknown environmental factors in children with specific HLA susceptibility genes. At the time of clinical diagnosis, the majority of the insulin-producing cells in the pancreatic islets have been eradicated in association with autoimmune phenomena including insulitis [1 ,2, 3], lymphocyte proliferation abnormalities [4,5,6] and autoantibodies to islet cell antigens [7±9]. Studies in first-degree relatives [7,8], twins [9], pregnant mothers [10,11] and school children [12,13,14] have found that islet autoantibodies can be present years before clinical diagnosis. Some [15±17], but not Diabetologia (1999) Summary Islet autoantibodies are early markers for Type I (insulin-dependent) diabetes mellitus. The aim of this study was to establish whether islet autoantibodies were present at birth in children who developed Type I diabetes before 15 years of age. Cord blood sera from 81 children who developed Type I diabetes between 10 months and 14.9 years of age were tested for glutamic acid decarboxylase autoantibodies (GAD65Ab), islet cell antigen 512 autoantibodies (ICA512Ab), insulin autoantibodies (IAA) all by quantitative radioligand binding assays and islet cell autoantibodies (ICA) by indirect immunofluorescence. Cord blood sera from 320 randomly selected matched children were controls. The children who developed Type I diabetes had an increased frequency of cord blood islet autoantibodies compared with control subjects: Glutamic acid decarboxylase autoantibodies were detected in 6 % (5/81) patients and 2 % (5/320) control subjects (p = 0.03); islet cell antigen 512 autoantibodies in 5 % (4/73) patients and 1 % (4/288) control subjects (p = 0.06); insulin autoantibodies (IAA) in 0 % (0/79) patients and 0.3 % (1/320) control subjects (p = 0.36); and islet cell autoantibodies in 10 % (8/81) patients compared with 0.6 % (2/320) control subjects (p = 0.0001). Taken together, 17 % (14/81) patients had one or more islet autoantibody compared with 4 % (12/320) control subjects (p = 0.0001). Whereas none of the control children had more than one antibody, 4 % (3/81) children who later developed Type I diabetes were double positive (p = 0.002). Although glutamic acid decarboxylase autoantibodies' concentrations in cordblood correlated to those in the mothers' blood at the time of delivery, no corresponding correlation was found for the other two types of autoantibodies. The increased frequency of cord blood islet autoantibodies suggests that the Type I diabetes process could already be initiated in utero. [Diabetologia (1999)

Because the prevalence of CD at diagnosis of IDDM would seem to be 6% to 8%, screening for CD seems to be justified among patients with newly diagnosed IDDM.

Context:The use of levothyroxine to reduce thyroid size in pediatric patients with goiter due to chronic autoimmune thyroiditis (AIT) remains controversial. In overtly hypothyroid patients, reductions in thyroid volume have been reported, whereas the effect in subclinically hypothyroid and euthyroid patients is less clear. Objective:The objective of the study was to evaluate the effect of levothyroxine treatment on thyroid size (determined with thyroid ultrasonography) in children and adolescents with AIT. Design and Setting: This study included patients with AIT treated at a university hospital outpatient clinic between 1987 and 2004.Patients: Ninety children with AIT (73 girls and 17 boys, aged 6.1-17.7 yr) were included in the study.Intervention: Intervention was treatment with levothyroxine for a median 2.8 yr (range 0.5-10.2).Main Outcome Measure: Change in thyroid volume SD score (SDS) during the study period was measured.Results: Median thyroid volume SDS was reduced in patients euthyroid (Ϫ0.4 SDS, P Ͻ 0.001), subclinically hypothyroid (Ϫ1.4 SDS, P Ͻ 0.001), and overtly hypothyroid (Ϫ1.8 SDS, P Ͻ 0.002) at diagnosis of AIT. Both hypothyroid and euthyroid patients with goiter (thyroid volume Ͼ 2.0 SDS) at baseline reduced their median thyroid volume SDS (Ϫ1.6 and Ϫ0.9, respectively, P Ͻ 0.001). Hypothyroid patients without goiter also reduced median thyroid volume SDS (Ϫ1.2, P Ͻ 0.004), whereas no change was noticed in euthyroid children without goiter. Conclusions:Levothyroxine treatment is effective in reducing thyroid volume in pediatric patients and is suggested in treatment of goiter caused by AIT, especially in cases of hypothyroid, but also in euthyroid children.

The design process has a significant impact on the performance and profitability of a housing project. Therefore, decisions made during the design process should take into consideration knowledge and experience from other processes in previously accomplished projects, specifically from the production phase. How to capture and use production experience in housing has not gained enough interest, possibly leading to suboptimal improvements during the construction process. This motivates research on how onsite production experience from similar previous projects can be captured and used to improve constructability without risking customer values. Based on the concept of constructability, 'design for manufacturing and assembly' and the theory of waste, the method 'design for construction' (DFC) has been developed. The four-step model complements the conventional construction process, and consists of the following steps: (1) specify customer values and similar previous projects; (2) identify onsite waste and cost drivers in previous projects; (3) develop criteria to evaluate constructability; and (4) evaluate constructability of the design. The DFC method is exemplified and tested through a case study, in which it was shown that the method facilitated identification of all problems that were considered in the investigated project. The method also highlighted other project obstacles that potentially could have been solved to improve constructability.