Magnetic damping: domain wall dynamics versus local ferromagnetic resonance.

Magnetic relaxation is one of the dominating features of magnetization dynamics. Depending on the magnetic structure and the experimental approach, different magnitudes of the damping parameter are reported even for a given material. In this study, we experimentally address this issue by accessing the damping parameter in the same magnetic nanotracks using different approaches: local ferromagnetic resonance (α=0.0072) and field-driven domain wall dynamics (α=0.023). The experimental results cannot fully be accounted for by modeling only roughness in micromagnetic simulations. Consequently, we have included nonlocal texture induced damping to the micromagnetic code. We find excellent agreement with the observed increased damping in the vortex structures for the same input Gilbert alpha when texture-induced nonlocal damping is included.

Anisotropic propagation and damping of spin waves in a nanopatterned antidot lattice.

All-electrical spin-wave spectroscopy, Brillouin light scattering, as well as the magneto-optical Kerr effect are combined to study spin-wave propagation through a magnetic antidot lattice nanopatterned into a Ni(80)Fe(20) thin film. The propagation velocities and, in particular, the relaxation are found to depend characteristically on the applied in-plane magnetic field. We explain the observed anisotropies by magnetic field-controlled spin-wave guiding in a network of interconnected nanowires which takes place over distances of up to 20 µm.

Work in progress: the web portal that brings together Cerec users and inLab laboratories--moving towards the impression-free dental practice.

Thanks to the compatibility of Cerec and inLab, the "impression-free" dental practice is just around the corner. Some final details remain to be clarified. An easy-to-use web portal is under development.

Effect of dietary fiber on the induction of colorectal tumors and fecal beta-glucuronidase activity in the rat.

The purpose of the present study was to investigate whether three different types of dietary fiber, wheat bran, carrot fiber, and citrus pectin, influenced the induction of colorectal tumors produced by 1,2-dimethylhydrazine in rats. In all groups, the tumor yield was high (87 to 97%). In the wheat bran and carrot fiber groups, the incidence of colorectal tumors was not significantly different from that of the group fed on the fiber-free basic diet. The citrus pectin group, however, had a significantly higher incidence of colorectal tumors (p less than 0.001). An increased number of auditory duct tumors was also noted in this group. In a separate experiment, dietary pectin induced a 10-fold increase in fecal beta-glucuronidase activity but did not alter this activity in the bowel wall. It has been suggested that dietary fiber protects against the induction of colorectal tumors, but this was not the case in the experiment. It is possible that the high tumor yield made the demonstration of a weak protective effect of wheat bran impossible. The reason for the increased occurrence of tumors in the citrus pectin group is obscure and will be subjected to further investigation. Fecal beta-glucuronidase activity might be one factor of importance in the activation of the carcinogen.

Effect of two kinds of pectin and guar gum on 1,2-dimethylhydrazine initiation of colon tumors and on fecal beta-glucuronidase activity in the rat.

The effect of 5% low-methoxylated pectin, high-methoxylated pectin, and guar gum on 1,2-dimethylhydrazine initiation of colon cancer was investigated using groups of 30 rats. The growth of the rats in the different groups was very similar to that of control group fed a fiber-free diet. Both kinds of pectin increased the multiplicity of color tumors, whereas guar gum did not significantly influence carcinogenesis. Bacterial beta-glucuronidase activity in feces and colonic content was the same in pectin-fed rats and controls but significantly lower in the guar gum group. Thus, it was not related to the number of tumors in each group.

Dipolar-energy-activated magnetic domain pattern transformation driven by thermal fluctuations.

Two-dimensional ferromagnetic layers can serve as a playground for the study of basic physical properties of various pattern forming systems by virtue of their tuneable magnetic properties. Here we use threshold photoemission magnetic circular dichroism in combination with photoemission electron microscopy to investigate ultra-thin ferromagnetic Fe/Ni/Cu(001) films in the stripe domain phase near the spin reorientation transition as a function of film thickness, temperature and effective anisotropy. Here we report a metastable domain state with domain width larger than the thermodynamically stable one as a result of a rapid reduction of the anisotropy. The transformation into the equilibrium state takes place via the propagation of a transition front, which originates from defined steps in the film thickness.

Transmission dynamics of highly pathogenic avian influenza at Lake Constance (Europe) during the outbreak of winter 2005-2006.

Highly pathogenic avian influenza virus (HPAI) H5N1 poses a serious threat to domestic animals. Despite the large number of studies on influenza A virus in waterbirds, little is still known about the transmission dynamics, including prevalence, behavior, and spread of these viruses in the wild waterbird population. From January to April 2006, the HPAI H5N1 virus was confirmed in 82 dead wild waterbirds at the shores of Lake Constance. In this study, we present simple mathematical models to examine this outbreak and to investigate the transmission dynamics of HPAI in wild waterbirds. The population dynamics model of wintering birds was best represented by a sinusoidal function. This model was considered the most adequate to represent the susceptible compartment of the SIR model. The three transmission models predict a basic reproduction ratio (R (0)) with value of approximately 1.6, indicating a small epidemic, which ended with the migration of susceptible wild waterbirds at the end of the winter. With this study, we quantify for the first time the transmission of HPAI H5N1 virus at Lake Constance during the outbreak of winter 2005-2006. It is a step toward the improvement of the knowledge of transmission of the virus among wild waterbirds.

Characterization of a group of transposed human V kappa genes.

A genomic region with three V kappa pseudogenes which has been transposed to chromosome 22 is characterized by detailed restriction mapping. A number of subclones are described one of which proved useful to establish an allelic restriction fragment length polymorphism (RFLP) in the region. Allelic and duplication-derived restriction site differences in cosmid clones are discussed with respect to possible problems in genomic walking experiments.

Significance of microbiological and biochemical analyses in empyema thoracis.

Following the indifferent results of a retrospective analysis, a prospective study was undertaken to analyse the causative organisms in 51 cases of empyema. Cultures were positive in 44/51 (= 86.3%) cases. 2 bacterial species were recovered for each empyema. The aerobic gram-positive cocci represented the largest group (57%), followed by aerobic gram-negative bacteria (18.6%), anaerobic bacteria (18.6%), and fungi (5.8%). Polymicrobial empyema accounted for 59.1% of the cases. Anaerobic bacteria were cultured from 36.4% of empyema. Anaerobic bacteria were more frequently isolated from pleural effusions than from other specimens. Swabs were found to be of minor value for anaerobics. Analyses of glucose and pH value in pleural effusions have been reported to be useful in differentiating complicated from uncomplicated effusions in cases where the aspirated fluid is not purulent and is negative on gram stain, but clinical as well as radiological findings point to an empyema. Our results have shown that pH-values less than 7.30 and Glucose less than 60 mg/dl were not absolutely specific for empyema. In contrast, PMN-elastase in pleural effusion and HI-30 in urine showed a statistically significant differentiation of empyema from exudates of other origin.

[The pathogen spectrum in acute and chronic pleural empyema]. / Erregerspektrum beim akuten und chronischen Pleuraempyem.

A retrospective analysis of the causative organisms was performed in 162 cases of empyema: 132/162 (= 81.5%) cases had positive cultures. Twenty-two different organisms were cultured from 235 isolates. The aerobic gram-positive bacteria were the largest group (61.7%), followed by aerobic gram-negative rods (21.7%), anaerobic bacteria (8.5%), and mycobacteria (5.1%). 1.8 bacterial species were recovered for each case of empyema. Polymicrobial empyema accounted for 48% of the cases. Therefore more than one antimicrobial agent should be administered to ensure adequate coverage.

[Rare pulmonary manifestation of an intracranial meningothelial meningioma]. / Seltene pulmonale Manifestation eines intrakraniellen meningothelialen Meningeoms.

HISTORY AND CLINICAL FINDINGS: A 53-year-old sailor was admitted to our department with the history of severe headache, dysphasia and mild psychotic behavior. Routine chest X-rays several weeks before had shown a focal lung lesion in the lower lobe of the right lung. The patient was without pulmonary symptoms. INVESTIGATIONS: Brain magnetic resonance imaging demonstrated a large intracranial extracerebral mass with perifocal brain edema in the right frontoparietal region. THERAPY: The patient was suspected of having a metastasis of an unknown primary tumor. Craniotomy and total removal of the tumor was performed. Histological examination revealed a meningothelial meningioma without signs of malignancy. 6 weeks later thoracotomy and total removal of the lung tumor were performed. Histological examination revealed a meningioma with the same histological pattern as the intracranial lesion. Postoperatively there were no complications, the physical examination at discharge was normal without any pulmonary or neurological deficits. Two years later, we found no evidence of an intracranial or pulmonary tumor recurrence. CONCLUSION: Pulmonary metastases of benign intracranial meningiomas are rare but should be considered in the differential diagnosis, especially in cases with an undiscovered primary tumor.

[Results and complications of treatment of acute and chronic pleural empyema--a retrospective analysis of the last 5 years]. / Ergebnisse und Komplikationen der Behandlung des akuten und chronischen Pleuraempyems--eine retrospektive Analyse der letzten 5 Jahre.

In 162 patients treated surgically for pleural empyema, 212 surgical interventions were necessary. As primary treatment cest-tube drainage was more effective than closed chest tubes. Decortication, which was carried out in 43 patients, was followed by further surgical procedures in three patients. If primary treatment is not effective early decortication is indicated to avoid septic complications (30-day mortality amounted to 7.4%). Two patients died from septic complications.

Wheat bran increases high-density-lipoprotein cholesterol in the rat.

1. Five groups of male Sprague Dawley rats were given for 6 months a diet with high protein and fat contents but a very low dietary fibre content (group B), and this diet mixed with (g/kg) 50 low-methoxyl pectin (group L), 50 high-methoxyl pectin (group H), 50 guar gum (group G) and 200 wheat bran (group WB, corresponding to 100 wheat fibre) respectively. 2. The weight increment was significantly lower in group G than in the other groups. Assuming no energy value of the dietary fibre, the weight increment (/kJ) was the same in groups B, L and H, lower in group G and higher in group WB, indicating that a proportion of the bran fibre might in fact be available as a source of energy. 3. Wheat bran increased total plasma cholesterol and high-density-lipoprotein cholesterol after 6, 12 and 26 weeks. Group G had significantly lowered plasma cholesterol after 12 weeks. Pectin on the other hand did not significantly influence total or HDL-cholesterol levels. It is therefore possible that the plasma cholesterol lowering effect of pectin previously demonstrated in the rat is dependent on the presence of significant amounts of dietary cholesterol as our diets did not contain added cholesterol. Plasma triglycerides decreased with age but were similar in all groups.

Tumor presence at resection boundaries and lymph-node metastasis in bronchial carcinoma patients.

A prospective study was performed analyzing the bronchial resection boundaries of 120 patients operated on for lung carcinoma. The resection boundary, maximum tumor diameter, distance between tumor and resection boundary, and lymph-node stage were analyzed by serial sections of the surgical specimens (lobes and lungs). The following results were obtained: 20/120 cases (17%) displayed microscopic tumor invasion of the resection boundary (R1 status), most frequently adenocarcinoma (21%). The R1 status was closely associated with the distance between tumor and resection boundary and postsurgical lymph-node state (pN stage): all 8 tumors excised at distance 1 mm or less from the bronchial resection boundary revealed bronchial submucous tumor growth, whereas none of the tumors located more than 20 mm from the resection boundary was found to display tumor invasion of the bronchial boundary. Curative resection was noted in all 40 tumors operated at pNO stage and in only 11 cases (69%) of tumors with distant lymph-node metastases (pN3 stage). No relationship between tumor infiltration of the resection boundary and type of resection was seen. The data indicate that a) intra-operative control of bronchial resection boundaries is necessary in all lung-carcinoma patients with central tumor localization less than 20 mm from the proposed resection boundary; b) a "safety distance" between resection boundary and tumor boundary is of specific importance in bronchial carcinoma with lymph-node metastases.

Dispersed human immunoglobulin kappa light-chain genes.

The gene segments encoding the constant and variable regions of human immunoglobulin light chains of the kappa type (C kappa, V kappa) have been localized to chromosome 2. The distance between the C kappa and V kappa genes and the number of germline V kappa genes are unknown. As part of our work on the human V kappa locus, we have now mapped two solitary V kappa gene and a cluster of three V kappa genes to chromosomes 1, 15 and 22, respectively. The three genes that have been sequenced are nonprocessed pseudogenes, and the same may be true for the other two genes. This is the first time that V-gene segments have been found outside the C-gene-containing chromosomes. Our finding is relevant to current estimates of the size of the V kappa-gene repertoire. Furthermore, the dispersed gene regions have some unusual characteristics which may help to clarify the mechanism of dispersion.

Molecular footprints of human immunoglobulin gene evolution: a new sequence family.

Analysis of the human VK (ref. 2) gene locus led to the detection of a new sequence family (L sequences). Its copy number is in the range of 10(2). The L sequences, which are about 500 bp long, are found as part of the 3' flanking regions of a clustered set of human VKI genes but they occur also separate from the genes. Models are discussed in which L sequences are viewed as molecular footprints of amplification and transposition processes of VK genes.

Non-invasive assessment of perioperative myocardial cell damage by circulating cardiac troponin T.

Troponin T is a unique cardiac antigen which is continuously released from infarcting myocardium. Its cardiospecificity as a marker protein might be particularly useful in assessing myocardial cell damage in patients undergoing cardiac surgery. Therefore, circulating troponin T was measured in serial blood samples from 56 patients undergoing cardiac surgery and in two control groups--22 patients undergoing minor orthopaedic surgery and 12 patients undergoing lung surgery by median sternotomy. In both control groups no troponin T could be detected, whereas activities of creatine kinase were raised in all 12 lung surgery controls and activities of the MB isoenzyme were raised in five of the 12 patients in the lung surgery group and in four of the 22 patients in the orthopaedic surgery group, respectively. All the patients undergoing coronary artery bypass grafting (n = 47) and cardiac surgery for other reasons (n = 9) had detectable concentrations of troponin T. Five patients had perioperative myocardial infarction detected as new Q waves and R wave reductions. In these five patients troponin T release persisted and serum concentrations (5.5-23 micrograms/l) reached a peak on the fourth postoperative day. In the 51 patients without perioperative myocardial infarction serum concentrations and the release kinetics of troponin T depended on the duration of cardiac arrest. In patients in whom aortic cross clamping was short troponin T increased slightly on the first postoperative days; in patients with longer periods of aortic cross clamping troponin T concentrations were higher and remained so beyond the fifth postoperative day. In patients with non-specific changes on the electrocardiogram troponin T concentrations were significantly higher on days 1 and 4 after operation than in patients with normal postoperative electrocardiograms(11.2 (5) and 4.5 (2.6) v 8.2 (3.4) and 2.9 (1.6) 1microg/l). Serum concentrations of troponin T showed some myocardial cell damage in every patient undergoing cardiac surgery. The persistent increases that were more common in patients with longer periods of cardiac arrest must have been caused by damage to the contractile apparatus. These results suggest that perioperative myocardial cell necrosis may be more common than indicated by changes of the QRS complex on the electrocardiogram.