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The present study investigates flow dynamics in the hub region of a wind turbine focusing on the influence of nacelle geometry on the root aerodynamics by means of Reynolds averaged Navier–Stokes simulations with the code FLOWer. The turbine considered is a generic version of the Enercon E44 converter incorporating blades with flat-back-profiled root sections. First, a comparison is drawn between an isolated rotor assumption and a setup including the baseline nacelle geometry in order to elaborate the basic flow features of the blade root. It was found that the nacelle reduces the trailed circulation of the root vortices and improves aerodynamic efficiency for the inner portion of the rotor; on the other hand, it induces a complex vortex system at the juncture to the blade that causes flow separation. The origin of these effects is analyzed in detail. In a second step, the effects of basic geometric parameters describing the nacelle have been analyzed with the purpose of increasing the aerodynamic efficiency in the root region. Therefore, three modification categories have been addressed: the first alters the nacelle diameter, the second varies the blade position relative to the nacelle and the third comprises modifications in the vicinity of the blade–nacelle junction. The impact of the geometrical modifications on the local flow physics are discussed and assessed with respect to aerodynamic performance in the blade root region. It was found that increasing the nacelle diameter deteriorates the root aerodynamics, since the flow separation becomes more pronounced. Possible solutions identified to reduce the flow separation are a shift of the blade in the direction of the rotation or the installation of a fairing fillet in the junction between the blade and the nacelle.

In an attempt to characterize a Peanut Agglutinin (PNA) autoantigen widely expressed in common human adenocarcinomas, monoclonal antibodies (MAbs) were made against PNA-affinity purified glycoproteins from pooled breast cancer membrane biopsy materials. Two IgM MAbs, 167H.1 and 167H.4, were found to react strongly with frozen tissue sections of various adenocarcinomas and the antigen was characterized further. By immunoprecipitation, western blotting, and gel filtration, both MAbs were found to react with a 67 kilodalton (kD) antigen. The 67 kD antigen was purified and determined to be specifically PNA reactive and naturally occurring antibodies were demonstrated to the purified antigen. In conclusion, the 167H.1 and 167H.4 MAbs identify a non-mucinous, PNA-reactive autoantigen widely expressed in human adenocarcinomas.

In a 66-year-old woman with suspected cholecystopathy, cholecystectomy led to the chance finding of the common liver fluke Fasciola hepatica (F.h.) in the common bile duct. Subsequent therapy with Dehydroemetin brought about regression of eosinophilia and of the pathologic immunofluorescent antibody test for F.h. The life cycle of F.h. and the clinical features of human infection are described in detail.

In a retrospective study the serological results from 1494 patients with community-acquired pneumonia were evaluated. An infectious etiology was found in about 40% of the cases. The majority of pneumonias was caused by Mycoplasma pneumoniae and by influenza virus type A, whereas Legionella pneumophila was the fifth most frequent pathogen. In the second part of the study, 13 hospitalized patients with community-acquired pneumonia were investigated by the whole panel of routinely used microbial methods. The etiological agent was found serologically in 3 cases and in one case by cultivation. These results suggest that the determination of serum antibodies against pathogens is frequently more useful than is generally assumed, although the yield of positive results is dependent on the epidemiological situation. The detection of elevated complement-fixing titers or specific IgM antibodies often leads to diagnosis from the first serum examined.

A 47-year-old man who had undergone gastrectomy for duodenal ulcer required repeated hospitalization due to recurrent fistulas in the region of the laparotomy scar and increased cholestasis and cachexia. An intrahepatic and subphrenic abscess was diagnosed clinically and by liver scan and confirmed by laparotomy. The histologic findings revealed actinomycosis. Through early surgical drainage and administration of 20 million units penicillin G daily it proved possible to discharge the patient completely cured after 2 months. The pathogenesis of liver actinomycosis is discussed.

Antifungal chemotherapy in weakened resistance is restricted to the following three substances: amphotericin B, 5-fluorocytosine and the azo dyes. The paper only discusses the therapy of indigenous iatrogenic fungal infections due to mycelial fungi (molds) and yeasts. The pathogenesis must be investigated in every case, since a healthy individual does not contract such a fungal infection. Prophylaxis would be more important than treatment of such complications. At the end of the paper, the therapy is summarized in a table. It is clearly seen from the table that the optimal modern therapy of systemic mycoses is a combination of 5-fluorocytosine in a normal dosage and amphotericin B at reduced dosage.

The clinical course and morphological findings are reported of visceral paracoccidioidomycosis or South American blastomycosis with lung involvement in a 47-year-old male after specific antimycotic treatment for 11 years. The patient had been infected during a stay in São Paulo, Brazil, from 1950 to 1954. The diagnosis was established in 1959 after his return to St. Gall, Switzerland, in tissue from buccal mucosa and cervical lymph node biopsy and in fungus cultures. The patient was treated with Fungizone (amphotericin B) and with the sulfonamide Fanasil. He died in 1970 from acute right heart failure. Autopsy revealed multiple encapsulated mycotic foci in both lungs, together with healed foci and pulmonary fibrosis. Histological examination showed a large amount of Paracoccidioides brasiliensis in the mycotic foci, but cultural proof was no longer possible. In the buccal mucosa and lymph nodes, only fungus-free scars were observed. There are only a few effective antimycotic agents. With a thorough knowledge of their side effects and dosage modalities, it is possible to achieve highly satisfactory results.

The author presents the most frequently observed pulmonary infections due to some opportunistic fungi (yeast, Aspergillus, Mucor). He describes the criterial for a correct diagnosis of pulmonary mycosis.

An outbreak of Salmonella typhi murium caused by person-to-person contacts was observed in Kurhaus (NE Switzerland) in late 1973. In all, 18 patients with clinical symptoms and 8 asymptomatic carriers were registered. However, 1 1/2 months elapsed before the etiologic diagnosis could be established. The infection was then transmitted, probably by a visiting nurse, to the personnel of a neighbouring school. An outbreak followed thereafter including 31 clinically manifest patients and 10 asymptomatic carriers. Infected food was most probably responsible for the dissemination of the disease, since two asymptomatic carriers were detected among persons engaged in the preparation of food. The close correlation between the two epidemics was confirmed by phague typing of isolated Salmonella strains according to the method of GUINEE. A common Biotype I, Lysotype 650, was identified in all cases. Clinical findings revealed diarrhea in 77,6%, fever in 59,2% and vomiting in 18.4% of cases. Only two patients who were admitted to the hospital, were given chemotherapy. The excretion of Salmonellae in the stools was observed on average for about one month in clinical cases and for 12 days in asymptomatic carriers. All the strains, with one exception, were in vitro sensitive against tetracycline, Chloramphenicol and trimethoprim-sulfamethoxazole. In one case the tetracycline treatment resulted in homologous resistance. In this case the carrier state had been observed for 111 days. Serologic tests were made one month after the outbreak was detected using Widal reactions with antigens of homologous strain. In most patients with clinical symptoms antibody titers were at serum dilutions of more than 1:80, whereas only 4 of the 9 asymptomatic carriers investigated presented with titers in this range. Patients who were not excreting Salmonellae had uniform antibody titers of less than 1:80.

The relatively high lethality of meningitis is due to the delay in beginning treatment (usually caused by nonrecognition of the disease) and to the greater age of the patient (associated diseases). New aspects of the improvement of the prognosis were not obtained by comparison of various patient collectives a decade apart in our clinic, although an improvement in additional measures such as artificial respiration occurred. The reason lies in veiling by antibiotic premedication. Before beginning antibiotic therapy an exact etiological diagnosis should be made. This objective can only be attained by better training of the physician, including neurology.

Three weeks after commencing oral contraception for the first time, a 26-year-old woman with a history of rheumatic carditis and chorea minor presented with sudden recurrence of hyperkinesis. Withdrawal of the contraceptive agent was followed by rapid remission of the hyperkinesis, which suggests a casual relationship between the contraceptive and this condition and an analogy between this case and so-called chorea gravidarum. A young non-pregnant woman presenting with chorea minor should be specifically questioned by ingestion of oral contraceptives. If there is a past history of rheumatic fever with or without chorea, oral contraceptives are contraindicated.

Although we are all carriers of fungi, an infection is rare. Therefore, the following questions are discussed: Why do these actually saprophytic germs become pathogenic at all? Why have opportunistic fungus infections increased? The diagnosis of a fungus infection due to saprophytic pathogens is difficult, as the demonstration of a fungus does not necessarily imply disease. The case history with relevant predisposing factors is an essential clue to the diagnosis. As a matter of principle, the diagnosis of a systemic mycosis should only be established by exclusion.

Following drug-induced agranulocytosis and antibiotic and steroid treatment, sepsis due to candida albicans together with bilateral fungal coxitis developed in a 41-year-old female patient. Satisfactory eradication of the inflammatory process was achieved with combined treatment with amphotericin B and 5-fluorocytosine, so that mobilisation was possible after surgical fitting of bilateral total endoprothesis.

An 85-year-old female diabetic was admitted in coma, having been on antidiabetic treatment with the biguanide derivative "Silubin retard", 600 mg/d, for one-and-a-half months. The anion deficiency was 57 mmol/l, pH 6.9, suggesting the diagnosis of lactic acidosis in the absence of other causes of metabolic acidosis. Blood lactic acid levels of more than 16.65 mmol/l (150 mg/100 ml) confirmed the diagnosis. Administration of 875 mmol sodium bicarbonate over 12 hours corrected the deficiency. On admission to hospital there had been slight pre-renal failure. Myocardial infarction developed as a result of tissue hypoxia but did not prove clinically important. On the second day there were signs of a compensated disseminated intravascular coagulopathy with upper gastro intestinal haemorrhage. The woman died suddenly 18 days later of pulmonary embolism.

Four primarily healthy patients with granulomatous hepatitis during acute cytomegalovirus infection are described. Granulomatous hepatitis associated with cytomegalovirus infection has been described previously in only 7 patients. As the authors have observed 4 such cases within a period of one year, this disease pattern may occur more frequently than was formerly assumed.

The clinical picture of pulmonary mycoses is described and discussed. The diagnosis of tropical pulmonary mycoses is--in contrast to the native mycoses--relatively simple with respective serological tests and intracutaneous reactions. For the diagnosis the differentiation of fungi or molds is of utmost importance.

The case is presented of a 48-year-old woman who, in association with repeated septic temperatures, developed abscesses in the region of the right shoulder and in the right ankly. Histological examination from excisates revealed caseous tuberculoid granulomas. Mycobacterium fortuitum was isolated from the pus of both abscesses. Although the Mycobacterium fortuitum was resistant to nine commonly used tuberculostatics, it was found to be sensitive to ethionamide and capreomycine. The use of these two drugs in combination with local measures proved successful.

In the differential diagnosis of gastrointestinal disturbances the possibility of laxative abuse is considered either too late or not at all. The sequel is a protracted course of illness with a series of expensive and fruitless investigations. On the basis of three recently observed cases of laxative-induced diarrhea the problems of diagnosis and management are discussed. Methods of securing early diagnosis are mentioned. The overall prognosis must be considered unfavorable. The importance is stressed of long-term follow-up of these patients at community level, to ensure timely intervention should complications arise and to prevent further unnecessary investigations.

alpha-Fetoprotein (AFP) has been shown to suppress a variety of immune responses in vitro. The immunosuppressive properties of AFP can be partly attributed to the ability of this protein to decrease the cell surface expression of Ia antigens on macrophages. The experiments described in this report define more precisely the regulatory effects of AFP on Ia expression. Using the "dendritic-like" cell line P388 AD2 and bone marrow-derived macrophages we have shown that AFP can suppress the constitutive expression of cell surface Ia antigens. This decrease is detectable on the cell surface 24 hr after the addition of AFP. In further experiments we also examined the effect of AFP on lymphokine-induced Ia expression. Our results show that AFP has no suppressive influence on the inductive phase of lymphokine-induced Ia antigen expression but can decrease elevated levels of Ia antigen subsequent to their induction.

A diphtheria epidemic in the eastern part of Switzerland in 1974 and the measures which were taken for its management and eradication are described. In particular it is pointed out that at present diphtheria displays atypical clinical symptoms in Europe, a fact that renders the diagnosis very difficult in many cases. Therefore, it is important to perform a throat swab in every patient with suspected diphtheria; it is also necessary to explicitly require a search for C. diphtheriae. The early recognition and early treatment of diphtheria with penicillin or erythromycin is of the utmost importance in order to avoid neurological and cardiac complications. With regard to the management and eradication of a diphtheria epidemic, the most important measures are rapid antibiotic protection of all contacts and a widespread immunization of the population. Vaccination of adults with a DiTe vaccine containing a reduced amount of Di-toxoid is recommanded.

Since therapy of an overt attack of rabies fails, we are completely dependent on prophylaxis. This must be carried out with extreme care. A careful detailed history is the most important, the fundamental question being: was this a provoked or unprovoked attack by the animal? In addition some knowledge of the behavior of different animals towards man is essential. Before every treatment, the question whether it is really necessary must be settled. The help of a veterinary colleague should be called upon in taking the history. A rapid diagnosis can be obtained by fluorescence serology of the dead animal.