Real-time finite element modeling for surgery simulation: an application to virtual suturing

Real-time finite element (FE) analysis can be used to represent complex deformable geometries in virtual environments. The need for accurate surgical simulation has spurred the development of many of the new real-time FE methodologies that enable haptic support and real-time deformation. These techniques are computationally intensive and it has proved to be a challenge to achieve the high modeling resolutions required to accurately represent complex anatomies. The authors present a new real-time methodology based on linear FE analysis that is appropriate for a wide range of surgical simulation applications. A methodology is proposed that is characterized by high model resolution, low preprocessing time, unrestricted multipoint surface contact, and adjustable boundary conditions. These features make the method ideal for modeling suturing, which is an element common to almost every surgical procedure. This paper describes constraints in the context of a Suturing Simulator currently being developed by the authors.     

Closing remarks at the symposium in honour of Daniel Bellus. Pharmacenter, University of Basel, February 6, 2009

In the Closing Remarks at the Symposium on 'Frontiers in Bioorganic Chemistry' (Friday, February 6, 2009, Pharmacenter, University of Basel) in honour of Daniel Bellus, his arrival in Zürich in fall 1967 and especially his postdoctoral work at the Laboratorium für Organische Chemie at the Eidgen?ssische Technische Hochschule (ETH) in Zürich throughout the year 1967/68 were mentioned. In his most remarkable paper (published in 1969 in Helv. Chim. Acta), the photochemistry of the alpha,beta-unsaturated cyclohexenones O-acetyl-testosterone and 10-methy-delta1,9-octalon-(2) is described in detail. Change of solvent leads to lowering or increasing of the n,pi*- and (pi,pi*)-triplet energies, resulting in a crossing of the two energy levels. Personal remarks on Daniel Bellus and warmest thanks to him, to Profs. Beat Ernst and Bernd Giese (the organizers of the symposium) and to all the speakers concluded this most special event.     

Space and time evolution of the plasma in a PDP cell: Comparisons between simulations and experiments

We have used a macroscopic discharge cell to study the space and time evolution of the plasma in geometry similar to real matrix and coplanar PDP cells with a scaling factor of around 100 (dimensions 100 times larger, pressure 100 times smaller, i.e., 1‐cm gap length, 5‐torr pressure). Discharges in pure neon and in a xenon‐neon mixture with 10% xenon have been investigated. The measurements have been compared with results from a two‐dimensional fluid model of the discharge.     

Aerosol exposure of pigs to viable or inactivated Actinobacillus pleuropneumoniae serotype 9 induces antibodies in bronchoalveolar lining fluids and serum, and protects against homologous challenge

A dose-defined nose-only inhalation system for pigs was used to study the immunogenic and protective potentials of a single aerosol application of viable or killed Actinobacillus pleuropneumoniae serotype 9. Respiratory volumes were measured for each pig to calculate inhaled individual doses. Eight pigs inhaled 107 CFU A. pleuropneumoniae CVI 13261 reference strain for serotype 9. Another eight pigs received an identical dose of killed actinobacilli. After three weeks the pigs and nonexposed controls were challenged with 108 CFU of the homologous strain by aerosol. Bronchoalveolar lavage (BALF) in pigs was performed during the experiment to obtain lavage samples for assessment of local antibodies. Isotype-specific antibody responses in serum and BAL fluids were measured by ELISAs based on whole-cell antigens. The protective efficacy of aerosol immunization was evaluated by clinical and post-mortem examinations. The controls developed fever and severe pleuropneumonia, whereas previously exposed pigs had less fever and less extensive gross pulmonary lesions. After the first aerosol exposure pulmonary IgM, and IgG antibodies reactive with A. pleuropneumoniae increased significantly in both aerosol exposed groups. IgA in BALF and serum concentrations of each Ig class were significantly increased in the group exposed to viable bacteria when compared to the non-exposed controls. After aerosol challenge a pronounced increase of systemic and pulmonary IgA, IgM, and IgG antibodies was detected in both exposure groups. Aerosol application of whole-cell A. pleuropneumoniae bacterins induced similar protective effects against aerosol challenge infection as administration of an identical dose of viable bacteria. Inhalation of A. pleuropneumoniae may lead to asymptomatic carriers in some pigs that could spread the disease under field conditions.     

Anlagensicherung mit Mitteln der Prozeßleittechnik

Plant Securing by Means of the Process Control Engineering. The Process control engineering contributes in an important way to the environmental protection and to the plant security in the chemical industry. Due to their historical evolution and the different forms of organization the enterprises have different, but equivalent safety conceptions by process control engineering. These different procedures have been synchronized and the results have been formulated in a NAMUR recommendation. The contribution gives an information about the most important results of this work.     

Analysis of associations between the prion protein genotypes and production traits in East Friesian milk sheep

The objective of this study was to analyze associations between ovine prion protein genotypes and production traits in East Friesian milk sheep. Production traits included the type traits scores for muscle mass, wool quality, and type; the reproduction traits age at first lambing, first lambing interval, second lambing interval, and total number of lambs born; the milk performance traits; milk, fat, and protein yields; fat and protein contents; and somatic cell scores. Prion protein genotypes were available for 658 East Friesian milk sheep. Linear animal models were used for the analysis of the prion protein genotype effects. The scores of the genotyped sheep for muscle mass, type, wool quality, and fat yield were significantly superior to those of the nongenotyped animals. An explanation for this might be that breeders seek to minimize genotyping costs by preselecting animals that do not meet the top breeding requirements. No significant associations were found between the prion protein genotypes and milk performance, type, or reproduction traits.     

Q-Fieber

Zusammenfassung:  Q-Fieber ist eine weltweit verbreitete Zoonose, die durch das hoch virulente Bakterium Coxiella burnetii hervorgerufen wird. Dieser Krankheitserreger bildet gegenüber Umwelteinflüssen resistente Dauerformen und wurde in vielen Tierarten nachgewiesen. Schafe, Rinder und Zecken bzw. deren Ausscheidungsprodukte sind die wichtigste Quelle für infektionen des Menschen. Bei den Wiederk?uern beschr?nken sich die klinischen Symptome im Wesentlichen auf Aborte. Von infizierten Tieren k?nnen die Coxiellen imVerlauf der Geburt massenhaft ausgeschieden werden. Insbesondere nach Inhalation kontaminierter Aerosole und Staubpartikel k?nnen epidemieartige Q-Fieber-Ausbrüche beim Menschen beobachtet werden. Akute Erkrankungsverl?ufe ?hneln grippalen Infekten und sind h?ufig selbst limitierend. Pneumonien und andere klinische Manifestationen k?nnen ebenfalls festgestellt werden. Chronische Verlaufsformen sind haupts?chlich durch Endokarditis bei pr?disponierten Patienten und granulomat?se Hepatitis gekennzeichnet. Dieser Artikel gibt einen überblick über Krankheitserreger, die klinischen Symptome bei Mensch und Tier, Epidemiologie und Ma?hmen zur Bek?mpfung des Q-Fiebers. Eingegangen: 27. Februar 2008; angenommen 5. M?rz 2008