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It has been previously shown that it is feasible to control the molecular weight distribution (MWD) of polymers produced from living polymerization processes in flow reactors through the control of reactant feeds. Here, attention is given to the problem of establishing an inverse process model as a step toward a fully automatic control strategy for the synthesis of polymers with predefined MWD. Particular attention is given to the prediction of instantaneous reactor feed conditions for a specified product MWD. The reactor is modeled as an ideal continuous stirred tank reactor with constant monomer concentration in the reactor. The way in which a real laboratory-scale polymerization system can be developed from this approach is outlined.

In this study the nodal staging sensitivity of sentinel lymph node biopsy (SLNB) with detailed pathological and molecular biological examination has been investigated and compared to that of axillary lymph node dissection (ALND) with routine histological evaluation. Sentinel lymph nodes (SLNs) were removed by the dual-agent injection technique in 68 patients with primary, clinically node-negative breast cancer. Forty-seven patients had negative SLNs according to hematoxylin and eosin (H&E) staining. These H&E-negative SLNs were serially sectioned and examined at 250 μm levels by anticytokeratin immunohistochemistry (IHC). In 14 patients the SLNs were also investigated by cytokeratin 20 (CK20) reverse transcriptase polymerase chain reaction (RT-PCR). SLNB with IHC increased the node-positive rate by 26% (by 40% in tumors less than or equal to 2 cm in size (pT1) and by 9% in tumors more than 2 cm but less than or equal to 5 cm in size (pT2)). The sensitivity of SLNB with IHC was superior to that of ALND with routine histology in pT1 tumors and identical in pT2 tumors. The concordance between histology and RT-PCR was only 21%, and in two of three cases with positive histological results RT-PCR was negative. In conclusion, SLNB with detailed pathological and/or molecular biological evaluation can improve the sensitivity of regional staging. ALND can probably be abandoned in patients with pT1 SLN-negative breast cancer. Further prospective studies are required to determine the clinical significance of these detailed SLN evaluation techniques, but at present these methods are still investigational.

A patient with two diseases, based presumably on different immunopathological mechanisms, hereditary angioedema (HAE) and Crohn's disease, was followed for 8 years. For more than three years of this observation period, detailed laboratory data were also available and could be analyzed. Both diseases had severe courses requiring chronic treatment with danazol and sulfasalazine, respectively. During exacerbation of Crohn's disease, the levels of C4 was found to be significantly lower than during the periods free of symptoms of both diseases. This drop was probably due to an impaired C1-inhibitor activity. HAE attacks and acute exacerbation of Crohn's disease never occurred simultaneously. This finding may be a mere chance but may also indicate that the different immunopathological processes underlying HAE and Crohn's disease influence each other.

The purpose of this paper is to show that there exist star-finite tree-structured sets in which the computations of parallel programs can be faithfully embedded, and that the theory of star-finite sets and relations therefore provides a new tool for the analysis of non-deterministic computations.

In process control application due to concurrency and resource sharing quite a few tasks has to be performed by the operating systen. This is usually solved by special programs like schedular and by the implementation of well known software tools like semaphores, critical regions etc.

The investigation of the PtCl2(diphosphine) + SnI2 and PtI2(diphosphine) + SnCl2 systems of catalytic importance (where diphosphines are 2,3-bis(diphenylphosphino)butane and 2,4-bis(diphenylphosphino)pentane) by NMR in solution has been carried out. Novel PtI(SnCl3)(diphosphine) and PtI(SnCl2I)(diphosphine) complexes were formed as a consequence of the halide exchange reaction. The selective formation of PtI(SnCl3)[2,4-bis(diphenylphosphino)pentane] was observed in the reaction of PtCl2[2,4-bis(diphenylphosphino)pentane] and 0.5 SnCl2 and 0.5 SnI2. PtI(SnCl3)[2,4-bis(diphenylphosphino)pentane], the first platinum complex which contains a chiral chelating diphosphine and SnCl3 ligand, was structurally characterized by X-ray diffraction.

Rooted plants and cuttings ofRosa indicawere dipped or sprayed withAgrobacterium radiobacterstrain 84 and planted in a commercial rose nursery. Crown gall was controlled effectively and equally well when the protectant inoculum was grown in broth or on agar and used for treating plants which were immediately planted in naturally infested soil (mean disease control was 91%). Untreated rooted-plant stock and unrooted cuttings had 20% and 0.7% galled plants, respectively, at the end of 8 months in the field; plants and cuttings dipped inA. radiobacter} inoculum had 0.6% and 0.1% galled plants, respectively. Spraying with inoculum also gave effective control of the disease. Fewer plants of the untreated nursery stock survived the 8 months between planting and harvesting than treated stock.

Sea surface temperatures (SSTs) observed near 60°S, 170°E during the spring and summer each year from 1957 to 1966 showed large year-to-year variations. The monthly mean SSTs in the springs of 1958, 1963, and 1964 were comparatively cold, but those in 1961 and 1966 were comparatively warm. Much smaller magnitude, nearly 2-yearly variations occurred in the monthly mean SSTs at Campbell Island (52° 40' S, 169° E) also.Surface pressure data were used to compute the geostrophic wind, wind-stress and wind-drift convergence and their yearly anomalies for the same periods. Theoretical transverse circulation models of the Antarctic Circumpolar Current applied to the observed wind distributions, provided plausible explanations of the yearly differences of the SSTs near 60° S.The largest SST and atmospheric circulation anomalies within the 10-year period occurred in the springs of 1963 and 1964. The nature of the anomalies suggested that they were indirectly related to the increase of atmospheric turbidity following the large volcanic eruption on Bali, Indonesia (8° 20' S, 115° 28 E), March 1963.

1.Bei 34 Frühgeborenen wurde das Verhalten der Lipoproteidverteilung in den ersten 9 Lebenswochen untersucht.2.Bei der Gesamtbetrachtung ist keine auffällige Altersabhängigkeit in den ersten Lebenswochen erkennbar, bei allgemein großer physiologischer Schwankungsbreite.3.Die Beobachtung von Einzelfällen zeigt bei der Mehrzahl ein ausgetragenen Säuglingen ähnliches Lipidogramm. Bei ca. 1/3 der Probanden bleibt der Wert der ß-Fraktion in dem beobachteten Zeitraum unter dem von reifen Säuglingen.4.In der Neugeburtsperiode tritt die markanteste Änderung vom 1. zum 2. Tag auf. Bei einem kleineren Teil zeigen die Lipoproteide schon am 1. Tag eine annähernd bleibende Verteilung.5.Ein Einfluß von zusätzlich verfüttertem Cholesterin läßt sich nicht sichern.6.Die Ergebnisse werden mit den Literaturangaben diskutiert und es wird versucht, sie in dei bisherigen Kenntnisse über den Fettstoffwechsel einzuordnen.7.Die kritische Beschäftigung mit der Methodik läßt einige Besonderheiten erkennen.

A leucodystrophy syndrome with Sudan-III positive lipids in the white matter was observed in a 7 months old boy who had shown clinical abnormalities from the first day of life. From an anatomo-clinical point of view the case compares best to cases described byZeman et al., although these were familial and the present case was not. In contrast to the central nervous system, cranial nerves and spinal roots did not show demyelination in routine preparations. Biochemical studies showed increase of both lipid and non-lipid hexosamine in the white matter and this was also found in 5 out of 21 cases of sudanophilic leucodystrophy (including P.-M.'s disease) collected from various laboratories. The quantity of alkali-and acid stable choline phospholipids (“sphingomyelin”) was normal in the grey matter and only slightly decreased in the white matter which seems to be at controverse with the fact that almost no stainable myelin could be detected, with the fact that the central nervous system was almost devoid of stainable myelin. This is also true in respect to the normal value for sulphatide measured in the white matter. Neutral cerebrosides, however, were extremely decreased in the white matter which is in accordance to the above mentioned absence of stainable myelin. No view is taken in regard to the pathogenesis of this condition because factual information is considered too scanty as yet.

The growth of a droplet of concentrated sulphuric acid suddenly exposed to water vapor was investigated. Droplet size and temperature as functions of time were obtained by numerical solution of droplet mass and energy balances. Inclusion of heat effects is thought to be an advance over previous studies of droplets of dilute acid which could be assumed to remain isothermal during the growth process. The results indicate that the growth process is completed in a few milliseconds for micron‐size droplets. The solutions presented are applicable to the continuum regime and the results are compared with experimental and calculated results of previous workers.

A simple complement-fixation test is described for serological investigations in typhus fever. The antigen consists of a washed suspension ofRickettsia prowazeki.Results obtained with 146 sera indicate that the serum of patients suffering from epidemic (European) typhus gives a well-marked fixation, while normal serum and the serum of patients in other diseases do not fix complement.The test becomes positive about two days earlier than the Weil-Felix test and thus may decide the diagnosis in early doubtful cases. With progressing illness both tests give positive result and the titre may run as high as 1∶8000. The results of the two tests are gemerally in correlation. A case of laboratory infection did not produce positive result in the Weil-Felix test but showed high titres in complement-fixation.Following three injections of a Cox-type vaccine 4 to 16-fold rise of the antibodies occured in humans as measured by the complement-fixation test, while the Weil-Felix test gave less definite results.Guinea-pigs infected or vaccinated withR. prowazekido not produce agglutinins against Proteus OX-19 as shown by the Weil-Felix test. Their serum, however, gives positive result in complement-fixation test.The practical application of the test is briefly discussed.

Background and Aims: The optimal treatment of clinically negative inguinal lymph nodes in patients with primary anal cancer has not yet been clearly defined. The presence of metastases in the inguinal lymph nodes is an adverse prognostic factor for anal cancer. In the present study the feasibility of sentinel lymph node biopsy (SLNB) for staging anal cancer was investigated.Patients and Methods: From September 1999 to March 2002, 8 patients with biopsy proven primary anal cancer underwent lymphoscintigraphy and dual-agent guided inguinal SLNB for nodal staging before starting multimodality treatment.Results: Inguinal SLNB was successful in all 8 patients (13 groins). A total of 20 hot and blue SLNs (mean 1,5 (1–2) per groins) were removed. In 2 patients (25 %) the SLN was positive for metastasis.Conclusions: Lymphoscintigraphy followed by dual-agent guided inguinal SLNB is technically feasible for staging patients with primary anal cancer. The detection of metastases in the removed sentinel lymph node(s) may alter the treatment and thus may improve the locoregional control and overall survival of these patients.