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Zusammenfassung Fur Ein- und Zweiplattengerate mit Schutzring wird das Temperaturfeld im Probekor-per fur kreisformige und quadratische Platten berechnet und hieraus der Fehler abgeleitet, der durch den Warmeaustausch am auβeren Rand des Schutzringes bei isothermen Heiz- und Kuhlplatten und idealem Warmekontakt entsteht. Der Fehler erweist sich als proportional zur reduzierten Temperaturdifferenz (Differenz zwischen mittlerer Probekorpertemperatur und Umgebungstemperatur geteilt durch Temperaturdifferenz zwischen Heiz- und Kuhlplatte), wodurch der Randfehler durch entsprechendes Einstellen der Umgebungstemperatur optimal verlkeinert werden kann. Experimente an einem Extruderschaum bestatigen die Folgerungen der rechnerischen Analyse. Fur Plattengerate gebrauchlicher Groβen ermoglichen Diagramme und Tabellen, die aufgrund der abgeleiteten Beziehungen berechnet wurden, eine Randfehlerabschatzung der jeweiligen Meβanordnungen.

It has been suggested that complete catch-up growth is achieved with treatment in patients with juvenile acquired hypothyroidism. We tested this assumption by examining long-term growth in 18 girls (mean [+/- SD] age, 11.4 +/- 2.7 years; bone age, 6.2 +/- 3.1 years) and 6 boys (age, 10.6 +/- 4.7 years; bone age, 6.4 +/- 2.7 years) with severe primary hypothyroidism (serum thyroxine level 1.1 +/- 0.3 micrograms per deciliter [13 +/- 4 nmol per liter]). At diagnosis, heights were 4.04 +/- 0.5 and 3.15 +/- 0.4 SD below the mean heights for age of normal girls and boys, respectively. The patients were treated with levothyroxine (3.4 +/- 0.3 micrograms per kilogram of body weight per day) to maintain normal thyroid function. During the first 18 months of therapy, the children's skeletal maturation exceeded the maturation expected for their statural growth, regardless of whether or not they were undergoing pubertal development. Predictions of decreased adult height were based on these observations. At maturity, girls and boys stood approximately 2 SD below normal adult stature, at 149 +/- 5.0 cm and 168 +/- 5.1 cm, respectively. Heights at maturity were also lower than midparental heights (P less than 0.01) and lower than pre-illness standard-deviation scores for height (P less than 0.01). The deficit in adult stature was significantly related to the duration of hypothyroidism before treatment (P less than 0.01). We conclude that despite treatment, prolonged juvenile acquired hypothyroidism results in a permanent height deficit related to the duration of thyroxine deficiency before treatment.

An 8 month old girl presented with undiagnosed non-anatomic congenital cardiomyopathy with massive cardiomegaly on chest X-ray film. Her older sibling had died suddenly at 6 months of age from what appeared to be a similar abnormality. Utilizing phosphorus-31 nuclear magnetic resonance (P-31 NMR) surface coil spectroscopy, a metabolic disorder was demonstrated in both her myocardium and skeletal muscle, revealing a phosphocreatine (PCr) to inorganic phosphate (Pi) ratio of half of that for a normal control infant. Manipulation of serum substrate availability indicated that medium chain triglycerides alone did not improve myocardial metabolism, but that intravenous glucose or oral carbohydrate loading raised the myocardial PCr/Pi ratio from 1.0 +/- 0.05 to 1.8 +/- 0.1 (p less than 0.01) without significantly affecting the PCr/Pi value of her resting skeletal muscle. This study demonstrates the feasibility of using P-31 nuclear magnetic resonance to evaluate the biochemistry of the human myocardium in vivo and to diagnose a metabolic abnormality. Phosphorus-31 nuclear magnetic resonance can thus be used to optimize therapy for human disease.

By cranial sonography through the open fontanelles of infants with hydrocephalus a diagnosis of position and function of ventricular shunts is possible. A malposition of the ventricular catheter was diagnosed sonographically in 11 of 55 patients after primary shunting. Complications after shunting as overdrainage or shunt insufficiency could be demonstrated early and reliable. Controls in due course are diagnostically important. The number of computerized tomographies in infants with hydrocephalus can be reduced significantly. In order to reduce complications after shunting an intraoperative sonographical control of catheter position is intended.

Flow velocities in the basal cerebral arteries were studied by transcranial Doppler sonography. A longitudinal study was undertaken on 25 healthy newborn babies during the first 20 days of life, and a cross sectional study was performed on 112 healthy children between 1 day and 18 years of age. A rapid linear increase of flow velocities was found within the first 20 days with higher velocities in neonates of higher birth weight and gestational age. Maximal values were recorded at the age of 5 to 6 years. After that the velocities decreased linearly to 70% of their maximum at the age of 18 years. Reference values were derived from the data considering age and birth weight. The increasing flow velocities probably reflect the increasing cerebral blood flow during the first years of life. Our results also support the hypothesis of a decrease in cerebrovascular resistance during infancy. With the technique of transcranial Doppler sonography and the introduced reference values normal and abnormal intracranial flow velocities can now be assessed by non-invasive methods in all paediatric age groups.

Pectin wastes are treated in a full scale anaerobic treatment plant which was built after extensive pilot test studies had been performed. The process used is an anaerobic activated sludge system. Between the reactor and the settling tank the mixed liquor passes through a vacuum degasser. This results in a proper settling of the return sludge. The efficiency of treatment is shown by a COD removal of 38 % and a BOD5 removal of 90 %.

Studies utilizing the administration of GnRH in various GnRH-deficient models have revealed the critical importance of the dose and mode of delivery of this releasing factor in determining the subsequent pituitary response. Chronic administration of long acting GnRH agonists (GnRHa), like continuous infusion of high doses of the native peptide, results in suppression of pituitary gonadotropin secretion. This selective and reversible suppression of gonadotropin secretion suggested several therapeutic applications for these analogs, particularly in the treatment of central precocious puberty (CPP), a disorder for which the previously available therapies lacked uniform efficacy and were associated with potential side effects. In our series, 74 children with CPP have been treated during the last 5 yr with the potent GnRH agonist, [D-Trp6, Pro9-ethylamide(NEt)]GnRH. Having selected a dose and route of administration that produced uniform suppression of spontaneous and stimulated pituitary gonadotropin secretion, GnRHa therapy resulted in a fall of gonadal sex steroid levels into the prepubertal range, a halting or regression of secondary sexual development, and a complete cessation of menses. Growth velocity slowed during therapy, with this slowing more pronounced during prolonged treatment periods and among those patients with more advanced chronological and skeletal ages. Skeletal maturation was retarded to a greater degree than linear growth, with resultant increases in the predictions for adult stature. Moreover, these benefits have been achieved in the absence of significant side effects. Complete reversal of the suppression of gonadarche has followed discontinuation of therapy; however, patterns of growth and skeletal maturation after discontinuation of GnRHa administration remain to be characterized. Thus, the impact of GnRHa therapy on final height must await further longitudinal study. The selective nature of GnRHa suppression of gonadarche also permits an investigation of the natural history of adrenarche and its discrete influences upon skeletal growth and maturation. In addition, GnRHa therapy of CPP provides a unique opportunity to study the effects of gonadal sex steroids on GH secretion and somatomedin-C (Sm-C) generation during sexual maturation. Finally, the detailed characterization of children with precocious puberty has helped to define more precisely a subset of patients whose precocity occurs in the absence of demonstrable gonadotropin secretion.(ABSTRACT TRUNCATED AT 400 WORDS)

The correlationbetween proteinturnoverand serum thyroidhormone levelswas studied in 10children,ages I to 16 yearssubsequent tosevereburn injuries. In contrast to published studies that have shown depression of triiodothyronine (Ti) and elevations of reverse Ti (rT:,) in stressed patients, no change was found in the mean level of Ti and a 69% decrease in rT:, compared to healthy controls of similar age. Whole body rates of protein synthesis and breakdown were determined using a I'5N)glycine turnover technique. The difference between synthesis and break- down was negatively correlated with the ratio, rT,/T, in serum. Thus, in burned children, a decrease in N balance was associated with a rise in rT3/T:, which is qualitatively similar to that observed in fasted individuals or in stressed patients who may be semistarved. Am. J. C/in. Nuir. 33: 1215-1219, 1980.

The "tethered cord syndrome" as a complication of spinal dysraphism is probably more important than assumed earlier. An abnormally low position of the conus medullaris is caused by different anomalies: e.g. adhesions, lumbosacral lipoma, tight filum terminale. In some patients no skinny changes can be detected. A "tethered cord syndrome" should be considered, if neuromuscular skeletal changes as club-foot, scoliosis, muscular atrophy of disturbances of gait, sensibility or function of bladder and rectum are recognized. It is also a result of a inadequately operated meningomyelocele. For experienced examiners sonography is an interesting non-invasive diagnostic procedure during infancy. The diagnosis should be completed by spinal computerized tomography and myelography. Surgery should be performed prophylactically. The "tethered cord syndrome" is explained by case histories of the University Hospital of Children, Freiburg.

The rates of glucose production and utilization can be estimated by a primed-constant infusion technique using separate catheters for the infusion of radiolabelled glucose and periodic blood withdrawal. In rats, a carotid artery catheter is most often combined with a jugular or femoral venous catheter in such studies. We presently describe a method which utilizes a single jugular catheter for both infusion and sampling in the awake rat. This method is directly compared with simultaneous carotid artery sampling during both the dynamic steady state and a nonsteady state induced by a constant infusion of insulin. Our results demonstrate the validity of a single vein design for the analysis of glucose kinetics in either state. Rapid sampling and complete flushing prevent disruption of infusate equilibrium and sample contamination respectively. This single catheter method requires less technical skill for placement, reduces surgical intervention and enhances the comfort of the awake rat.

The interrelationship between mixing characteristics and tracer response curves in activated sludge tanks is explained. In some cases the return sludge cycle has a strong influence on the tracer response curves. Results from tracer tests in the field are hard to interpret because the tracer in the return sludge interferes with the initial tracer. Therefore a special evaluation procedure has to be applied. The paper closes with results from a field tracer test study.

After a 5 years' experience of cerebral sonography (about 4,500 recordings) in infants we are trying to establish correlations between alterations of anatomical structures and the further clinical development. Obviously there is no constant connexion between a simple subependymal haemorrhage and the further neurological symptoms. At the age of two and more years, about 30% had a normal state, the other part had very different clinical signs. Even an uncomplicated ventricular haemorrhage had no definite influence on the child's development in most cases. Ischemic infarctions seem to have a better prognosis than borderline-infarctions. Real intracranial cysts and slight brain atrophy seem to have only distinct neurological symptoms. Porencephalic defects or brain necrosis, e.g. after parenchymatous haemorrhages and infarctions as well as generalized hypoxic encephalopathies with increased echogenicy and progressive brain atrophy nearly always showed neurological defects, though the dimension of the brain's alteration does not clearly correlate to the clinical symptoms and the child's development. It is not possible to make a prognostic evaluation by cerebral sonography in hypoxic-ischemic brain-lesions within the first 3 weeks post partum. A more exact judgement will be given after further regular sonographic observations in all high-risk infants within the first year. Beyond this, technical and organisation-improvements will probably allow a more exact statement in future.

The principles of high-rate denitrification are explained. In the experimental section of the paper the results of nine lab-scale experiments are described and compared with data gained from reviewed literature. The tests were performed in continuous flow stirred-tank and wash-out reactors under mesophilic and thermophilic conditions. The experimental results confirm that high-rate denitrification is an extremely efficient process. Removal rates of up to 25 kg NOx-Nel./ (m3·d) were achieved with the activated sludge systems. The nitrate sludge loading was found to be the significant design parameter for the process if there is an excess of organic substrate. The maximum rate achieved by thermophilic bacteria was 10 kg NOx-Nel./(kg MLVSS·d) which exceeded by 33 % that for mesophilic organisms. Due to this, in the wash-out reactors the thermophilic system was superior to the mesophilic at system-related, inevitably similar MLVSS concentrations. But because of a temperature-dependent type of growth (thermophilic: disperse; mesophilic: flocculating), in the case of systems with recycling of biomass, higher removal rates (per volume) were obtained for the mesophilic reactors.

Goiters are rarely palpable in infants with congenital hypothyroidism except in the case of maternal ingestion of iodide. The presence or absence of glandular tissue is, however, important for genetic and prognostic counseling and for acceleration of diagnosis in other affected siblings. The detection of thyroid tissue by /sup 99m/Tc pertechnetate scans in a significant number of our patients heretofore considered athyreotic establishes that physical findings and traditional laboratory data are not adequate to determine whether or not thyroid tissue is present.

Recent evidence suggests that a group of children exists in whom premature sexual maturation occurs in the absence of pubertal levels of gonadotropins; that is, they have gonadotropin-independent precocious puberty. We compared six boys and one girl with this disorder with four boys and five girls with central precocious puberty, in which there is a pubertal pattern of gonadotropin release. The two groups were similar in age of onset, degree of sexual development, growth velocity, and rate of skeletal maturation. A family history of precocity was noted in four of the boys with gonadotropin-independent precocity, and the girl had McCune-Albright syndrome. Children with central precocious puberty demonstrated a pulsatile release of gonadotropins, pubertal responses to luteinizing hormone-releasing hormone, and complete suppression of gonadarche after exposure to an analogue of luteinizing hormone-releasing hormone (LHRHa). In contrast, children with gonadotropin-independent precocity demonstrated an absence of gonadotropin pulsations, variable responses to luteinizing hormone-releasing hormone, lack of suppression of puberty in response to LHRHa, and cyclic steroidogenesis. Tissue from testicular biopsies performed in five of six boys with gonadotropin-independent precocity showed a range from incipient pubertal development of the tubules with proliferation of Leydig cells to the appearance of normal adult testes. We conclude that gonadotropin-independent precocious puberty is a distinct syndrome, of unknown cause, that may be familial and may have been responsible for many previously reported cases of precocious puberty.

The blood flow velocities in the basal cerebral arteries can be recorded at any age by transcranial Doppler sonography. We examined nine children with either initial or developing clinical signs of brain death. Soon after successful resuscitation increased diastolic flow velocities indicated a probable decrease in cerebrovascular resistance; this was of no particular prognostic importance. As soon as there was a clinical deterioration, there was a reduction in flow velocities with retrograde flow during early diastole, probably due to an increase in cerebrovascular resistance; this indicated a doubtful prognosis. In eight of the nine children with clinical signs of brain death a typical reverberating flow pattern was found, which was characterised by a counterbalancing short forward flow in systole and a short retrograde flow in early diastole. This indicated arrest of cerebral blood flow. One newborn showed normal systolic and end diastolic flow velocities in the basal cerebral arteries for two days despite clinical and electroencephalographic signs of brain death. Shunting of blood through the circle of Willis without effective cerebral perfusion may explain this phenomenon. No patient had the typical reverberating flow pattern without being clinically brain dead. Transcranial Doppler sonography is a reliable technique, which can be used at the bedside for the confirmation or the exclusion of brain death in children in addition to the clinical examination.

An athyrotic infant had hypothyroidism at 1 year of age. He had grown at an above-average velocity until age 10 months when breast-feeding was discontinued, yet his bone age remained that of a newborn. These observations suggested that breast-feeding had attenuated hypothyroidism by providing significant quantities of thyroid hormones in the milk. To test this hypothesis, thyroxine (T4), 3,5,3'- triiodothyronine (T3, and 3,3',5'-triiodothyronine (reverse T3) were measured in breast milk samples collected serially from three months before to four months after delivery. Mean breast milk T4 content fell from 1.4 to 0.7 µg/dl within 48 hours after delivery, while T3 content rose from 136 to 286 ng/dl. Reverse T3 content remained unchanged. The shift in the T4/T3 ratio after delivery was observed in samples of all five donors; the highest postpartum T4 level was 1.1µg/dl and the highest postpartum T3 level was 405 ng/dl. It is concluded that breast-feeding may deliver sufficient thyroid hormones to the athyrotic infant to mitigate severe hypothyroidism and to prevent impaired neurological development.

Cold-exposed rats exhibit hypermetabolism, hyperphagia, and increased glucose oxidation. Their counterregulatory hormone secretion is markedly elevated, while insulin levels fall acutely, gradually returning to basal during acclimation. We assessed both hepatic and peripheral sensitivity to insulin in rats in the basal state and after 5 days of cold (5 C) exposure. The contribution of gluconeogenesis to total glucose turnover was measured and compared to daily urinary corticosterone excretion. Hepatic glucose production was equally suppressed by the infusion of insulin at 1.2 mU/kg X min in both control and cold-acclimated rats, but enhanced hepatic sensitivity to low dose (0.6 mU/kg X min) insulin infusion was only observed after cold exposure. The metabolic clearance of glucose was elevated with cold stress and was insensitive to the infusion of insulin at either level. Insulin resistance was not observed. Urinary excretion of corticosterone and urea nitrogen were markedly increased, but creatinine excretion was unchanged, suggesting that the concurrent increase in gluconeogenesis resulted from increased protein intake rather than increased catabolism of muscle protein.

By cranial ultrasound extracerebral fluid collections with a thickness of more than 5 mm were diagnosed in 101 infants under 1 year of age (jan. 84-dec. 85). Well-known etiologic factors were found in many cases (subdural hygroma, bacterial meningitis, shunt-dysfunction, congenital malformations, ACTH-therapy). In 38 children with normal clinical and neurological aspect no definite cause could be detected. In case of normal head circumference we consider this state as a variation of the norm. In case of macrocephalus (greater than 97th percentile) we propose the terminus "cranio-cerebral dysproportion". Possible etiologies, diagnostic procedures and differential diagnosis are discussed. The knowledge of this benign condition is important to prevent children from unnecessary diagnostic and therapeutic procedures.

Metabolic defects in obese (fa/fa) Zucker rats have previously been shown to be reversed by adrenalectomy; however, hypercorticosteronemia has not been demonstrated. We now report that the total daily excretion of corticosterone and urea nitrogen are significantly greater (P less than 0.01) in obese Zucker rats than in age-matched lean Zucker rats. This excessive excretion of corticosterone is not of autonomous adrenal origin, since dexamethasone treatment (20 micrograms/kg X day) for 2 days induced a proportionate reduction in corticosterone excretion (approximately 50%) in both obese and lean Zucker rats. Corticosterone excretion was further suppressed to levels not different from those in lean rats after 2 days of dexamethasone (40 micrograms/kg X day). Both the peak and total pituitary beta-endorphin secretion in response to an iv bolus of corticotropin-releasing factor (CRF) were diminished in obese Zuckers. The response to CRF in obese Zucker rats was dampened and superimposable on that of dexamethasone-treated lean Zucker rats, suggesting the existence of chronic hypercorticosteronemia as a component of this genetic obesity. These observations provide evidence for a compensatory alteration of the pituitary-adrenal axis. We suggest that corticosterone turnover may be increased in obese Zucker rats.

The paper evaluates the question of whether a combined anaerobic-aerobic or a solely aerobic treatment of some particular industrial wastewaters leads to better results. Therefore three different industrial wastewaters were treated in two different process lines: one line consisted of anaerobic treatment prior to aerobic treatment and in the other, only aerobic treatment was applied. The experiments were run with wastewater from:–the pectin industry–the sugar industry (beet sugar)–the animal pulp industry. The data presented in this paper were gained from experimental work which was conducted over a period of two years. Different scales of treatment plants were used. The anaerobic treatment was done in full- and semitechnical scale reactors, while the aerobic treatment took place in labscale and semitechnical scale plants. Surprisingly in all three cases the solely aerobic treatment led to slightly better results in terms of residual pollution. Finally the paper presents data gained from a recently built, full-scale anaerobic-aerobic process which treats pectin waste. The aerobic stage of the process was designed on the basis of the results from the experimental work which was mentioned above. The results from the former experimental work and from the full-scale operation are compared.

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The therapeutic efficiency of Chlorpropamide was evaluated in three patients with hypodipsia and diabetes insipidus. Hitherto extraordinarily difficult management problems, the patients responded with recovery of homeostatically appropriate thirst, improved renal concentrating ability and normalization of serum tonicity. Tests of their responses to fluid loading and water restriction indicated that normotonicity was protected during treatment through wide ranges of fluid intake varying from 2.2 to 5.0 L/twenty-four hours. Over a period of one year of treatment the patients have maintained normal fluid and electrolyte homeostasis despite abandonment of the strict fluid and diet regimens previously required to prevent wide swings in tonicity. Evidence is cited in support of the tenet that the beneficial effect of the sulfonylureas at the renal level depends upon amplification of the response of the adenyl cyclase system to residually low but facultatively controlled levels of vasopressin. The reappearance of appropriate drinking behavior during chlorpropamide treatment is probably similarly mediated, being attributable to a step-up of attenuated neural discharges by an effect of the drug on nucleotide system(s) in the brain.

Es wird ein Uberblick Uber den Stand und die neue Aufgabenstellung bei der Entwicklung elektrochemischer Stromquellen (Brennstoffzellen, Primarzellen, aktivierte Zellen und Akkumulatoren) gegeben. Auser den schon lange bekannten und weitentwickelten Systemen tritt die Forderung nach neuen, meist hochenergiereichen Zellen fur spezielle Zwecke (z. B. Weltraumfahrt) auf.

The observation that dexamethasone given normal individuals as a single dose at midnight results in low levels of plasma cortisol at 8:00 a.m., presumably by inhibiting the early-morning pituitary discharge of ACTH, stimulated investigation of the therapeutic value of dexamethasone so administered to patients with congenital adrenocortical hyperplasia. Detailed studies on four patients are presented. Results of short-and long-term treatment suggest that single, appropriately timed doses of 0.25 to 0.75 mg daily cause normalization of urinary 17-ketosteroid and pregnanetriol output, provide sufficient daily glucocorticoid for bodily needs, and simplify therapy for this disorder in adults and adolescents who have reached their mature height.

Phosphofructokinase from baker's yeast has been purified 370-fold. The purified enzyme is homogeneous as judged by analytical ultracentrifugation and disc electrophoresis. It exhibits the kinetic properties reported for phosphofructokinase from yeast and other sources. The purified enzyme is very sensitive to inhibition by ATP. The inhibition is pH-dependent with a maximum around pH 7.5. The influence of different effectors on the enzymatic activity and on the inhibition by ATP are described. NH4+ ions cause a general stimulation of enzymatic activity, while the sensitivity to ATP is abolished. ADP inhibits the enzyme at non-inhibitory ATP levels and stimulates the activity at inhibitory concentrations of ATP. Phosphoenolpyruvate is a negative effector. Inorganic phosphate inhibits the activity by competition with Fru-6-P and increases the inhibitory effect of ATP.

(1924). Why Educational Objectives? The Journal of Educational Research: Vol. 10, No. 3, pp. 175-186.

The proximity of the TBG deficiency locus to those for Xg, protanomaly and deuteranomaly was studied by linkage analysis. The data were derived from one large family of five generations. No evidence for linkage of TBG deficiency to these other X-chromosome loci was found; the data provide strong evidence against any close linkage.

(1923). The Educational Significance of Mental Tests. The Journal of Educational Research: Vol. 7, No. 2, pp. 91-99.