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Traditional learning curve theory is applied to surgical procedures in a German hospital to analyze financial strategies under prospective payment system competition. Findings from 601 knee replacement arthroplasties performed from 1994 to 2000 indicate learning curve theory is a useful tool to examine hospital financial strategies.

Background: Nonmelanoma carcinomas of the skin represent the most frequent cancers among the Caucasian population worldwide. They occur with high frequency in renal allograft recipient patients after prolonged immunosuppression. Purpose: We analyzed tumors obtained from both immunosuppressed and nonimmunosuppressed patients for human papillomavirus (HPV) DNA. Methods: Twenty-nine specimens of nonmelanoma carcinomas of the skin were obtained from 19 renal allograft recipient patients; these included 20 specimens of squamous cell carcinoma (SCC) from 11 patients, five specimens of basal cell carcinoma (BCC) from four patients, and four specimens of carcinoma in situ (CIS) from four patients. Forty-one specimens of nonmelanoma carcinomas of the skin were obtained from 32 nonimmunosuppressed patients; these included 26 SCC specimens from 19 patients, 11 BCC specimens from nine patients, and four keratoacanthoma (benign epithelial tumor) specimens from four patients. A polymerase chain reaction method involving use of degenerate oligonucleotide primers, in which the conserved region of the open reading frame of the HPV L1 (major capsid protein) gene is amplified, was used to amplify total cellular DNA purified from individual tumors. The DNA of each specimen was subjected to 16 different amplification reactions; different primer combinations were used in order to increase the sensitivity and specificity of HPV detection. Resulting products were probed with a radioactively labeled, degenerate oligonucleotide. HPV-specific DNA was either sequenced directly after elusion from the gel or amplified with semi-nested, degenerate primers, after which the products were cloned and sequenced. Sequences were compared with all known papillomavirus sequences. Results: Thirteen (65%) of the 20 SCC specimens and three of the five BCC specimens from immunosuppressed (renal allograft recipient) patients contained identifiable HPV-related sequences, among them 13 putative novel HPV genomes. In addition, all other malignant tumor specimens from this patient group revealed faint signals upon amplification and hybridization; the origin of these signals has not been identified in the present study. In nonimmunosuppressed patients, eight (31%) of 26 SCC specimens and four (36%) of 11 BCC specimens contained sequences of HPV types. Two putative novel HPV sequences could be identified in this group. Faint signals of yet undetermined origin were observed in eight of the SCC specimens and in two of the BCC specimens. Two of four keratoacanthoma specimens contained sequences of known HPV type. (Keratoacanthoma is a nonmalignant lesion for which the natural history has not been defined.) The spectrum of HPV types in both groups of patients differed substantially. Conclusions: These data point to the frequent presence of HPV sequences in SCCs and BCCs of the skin. The etiologic relationship of these infections to the respective malignant tumors remains to be evaluated. Implications: The presence of HPV DNA in a large percentage of specimens of nonmelanoma carcinomas of the skin from immunosuppressed patients, as well as from nonimmunosuppressed patients, renders a papillomavirus infection as a possible factor in the etiology of this disease.

JUST ten years ago, Tokyo Bay was a polluted, stagnant body of water: smelly, visually opaque, and nearly devoid of marine life. Today the city has turned that situation around, […]

Uniparental disomy (UPD) describes the inheritance of a pair of chromosomes from only one parent, either as both homologues (heterodisomy), as two copies of one homologue (isodisomy), or as a [...]

Presents an event manipulation for discrete simulation on large numbers of events. Problems on the flexibility of scheduled events; Creation of events in a simulated time; Proper handling of simultaneous events.

A technique for simulating the detailed logic networks of large and active digital systems is described. Essential objectives sought ore improved ease and economy in model generation, economy in execution time and space, and a facility for handling simultaneous activities. The main results obtained are a clear and useful separation of structural and behavioral model description, a reduction of manual tasks in converting Boolean logic into a structural model, the elimination of manual processes in achieving exclusive simulation of activity, an event-scheduling technique which does not deteriorate in economy as the event queue grows in length, and a simulation procedure which deals effectively with any mixture of serial and simultaneous activities. The passage of time is simulated in a precise, quantitative fashion, and systems to be simulated may be combinations of synchronous and asynchronous logic. Certain aspects of the techniques described may be used for the simulation of network structures other than digital networks. [ABSTRACT FROM AUTHOR]

Once considered merely as a vehicle for spermatozoa, it is now clear that seminal plasma (SP) induces a variety of biological actions on the female reproductive tissues able to modulate the immune response against paternal antigens. To our knowledge, the influence of SP on the immune response against sexually transmitted pathogens has not been yet evaluated. We here analyzed whether the seminal vesicle fluid (SVF), which contributes almost 60% of the SP volume in mice, could modulate the immune response against herpes simplex virus type 2 (HSV-2). We found that SVF does not modify the course of primary infection, but markedly improved protection conferred by vaginal vaccination with inactivated HSV-2 against a lethal challenge. This protective effect was shown to be associated to a robust memory immune response mediated by CD4+ and CD8+ T cells in both the lymph nodes draining the vagina and the vaginal mucosa, the site of viral replication. In contrast with the widespread notion that SP acts as an immunosuppressive agent, our results suggest that SVF might improve the female immune response against sexually transmitted pathogens.

The advent of FTIR microscopic spectrometers with focal plane array detectors enabled rapid image acquisition with diffraction limited lateral resolution. The field of view depends on the magnification and the detector size. FTIR images of large samples can be collected in the so called mosaic mode by stitching individual images together. If the mosaic is composed of hundreds of images, the total acquisition time and the data size will increase considerably. One computational and two optical options are compared to reduce both acquisition time and data size. First, the 2× field expansion optic increases the measured sample area fourfold. Second, using a 4× objective instead of the standard 15× objective increases the area covered by a single image by a factor of 11. Third, pixel binning averages neighboring pixels at the expense of lateral resolution. All options are demonstrated in a case study of a thin section of laryngeal carcinoma encompassing normal tissue, inflammation, connective tissue, dysplasia, carcinoma and blood. Data analysis is described using the toolbox hyperSpec operating under the R environment and complemented by parallel computing functions. A classification model that was trained with low magnification data in the range from 1200 to 1800 cm−1gave similar results for higher magnification data. Restrictions occurred for microscopic features smaller than the detector pixel size and for biomarkers below 1200 cm−1due to signal attenuation of the 4× objective lenses. FTIR imaging mosaic strategies of other groups and the emerging use of quantum cascade lasers for IR imaging are discussed.

Mount Cameroon is characterized by an elongated summit plateau, steep flanks, and topographic terraces around its base. Although some of these features can be accounted for by intrusion‐induced deformation, we here focus on the contribution of edifice‐scale gravitational spreading in the structure of Mount Cameroon. We review the existing geological and geophysical data and morphostructural features of Mount Cameroon and surrounding sedimentary basins. Volcanic ridge gravitational spreading is then simulated by scaled analogue models on which fault formation is recorded using digital image correlation. Three sets of models are presented (i) models recorded in cross section (Type I), (ii) models recorded from above with a uniform (Type IIa), and (iii) nonuniform ductile layer (Type IIb). Type I models illustrate the formation of faults accommodating summit subsidence and lower flank spreading. Type IIa models favor displacement perpendicular to the long axis, with formation of a summit graben and basal folds, but fail to reproduce the steep flanks. Type IIb models investigate the effect of spatial variations in sediment thickness and/or properties consistent with geological evidence. Directional spreading of the volcano's central part perpendicular to the long axis is accounted for by a sediment layer with restricted lateral extent and increasing thickness away from the volcano axis. The later model closely reproduces key features observed at Mount Cameroon: steep upper flanks are accounted for by enhanced lateral spreading of the lower flanks relative to the summit. The relevance of these findings for understanding flank instabilities at large oceanic volcanoes is finally highlighted. Mount Cameroon morphology provides evidence of gravitational deformationDynamics of the deformation is analyzed through analogue modelsDirectional flank spreading over nonuniform weak sediments controls deformation

The magnetic properties of two octahedral iron(II) complexes with Schiff base like equatorial N2O2coordinating ligands and methanol (MeOH) as axial ligand are reported. Both compounds [FeL1(MeOH)2] (1) and [FeL2(MeOH)2] (2) (with L1 = [3,3′]‐[1,2‐phenylenebis(iminomethylidyne)‐bis(2,4‐pentanedionato)(2‐)‐N,N′,O2,O2′] and L2 = [E,E]‐[{diethyl 2,2′‐1,2‐phenylenebis(iminomethylidyne)bis(3‐oxo‐3‐phenylpropanato)} (2‐)‐N,N′,O3,O3′]) show a weak spontaneous magnetization below TC= 10 K. Results from X‐ray structure analysis of 1indicate, that this is due to 2D network of hydrogen bonds as previously discussed for a similar complex.

The influence of various geometric factors on 131I uptake measurements for solitary thyroid nodule was systematically investigated to derive an approach, based on routinely performed ultrasound examinations, to correct for the effect of geometric variations.

CuII complexes of different 6-(β-keto-enamino)-6-deoxy-1,2-O-isopropylidene-α-D-glucofuranoses 3a–f have a high tendency to build up oligonuclear clusters. Two new oligonuclear copper(II) complexes could be synthesised, crystallised and their structures determined. The complex Cu(3a) was found to consist of a heptanuclear cluster in which two β-cubane like substructures share one copper ion. The structure is highly asymmetric and in the cluster every CuII ion has a different coordination geometry. Variation of the residues of the β-ketoenaminic unit leads to the formation of the octanuclear copper(II) complex Cu(3e). Similarly, this has two β-cubane subunits consisting of a heptanuclear structure with an additionally attached copper ion. In the crystal, two Cu8 cluster molecules are found differing in their geometries due to intermolecular interactions responsible for the formation of a supramolecular network. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

AbstractHeart rate variability (HRV) is a marker of autonomous activity in the heart. An important application of HRV measures is the stratification of mortality risk after myocardial infarction. Our hypothesis is that the information entropy of HRV, a non-linear approach, is a suitable measure for this assessment. As a first step, to evaluate the effect of myocardial infarction on the entropy, we compared the entropy to standard HRV parameters. The entropy was estimated by compressing the tachogram with Bzip2. For univariate comparison, statistical tests were used. Multivariate analysis was carried out using automatically generated decision trees. The classification rate and the simplicity of the decision trees were the two evaluation criteria. The findings support our hypothesis. The meanNN-normalized entropy is reduced in patients with myocardial infarction with very high significance. One entropy parameter alone exceeds the discrimination strength of multivariate standards-based trees.

Microanalysis on the 10-nm level using imaging, diffraction, and spectroscopy of slow photo-emitted and reflected electrons is discussed. The instrumentation that uses a cathode lens is briefly reviewed, and a number of applications illustrate the power of this microanalysis method.

To estimate the individual absorbed dose to the parotid and submandibular salivary glands in radioiodine therapy and its dependence from the previous cumulative therapy.

We analyzed 74 cryostat sections of central gastric tumor, tumor margin, and normal gastric epithelium using ProteinChip Arrays and SELDI-TOF MS. One peak was significantly down-regulated in tumor tissue (P = 1.43 × 10^-6) and identified as pepsinogen C using MS/MS analysis and immunodepletion. This signal was further characterized by immunohistochemistry. This work demonstrates that differentially expressed signals can be identified and assessed using a proteomic approach comprising tissue-microdissection, protein profiling, and immunohistochemistry. Keywords: gastric cancer • proteomics • biomarker • ProteinChip technology • SELDI • microdissection • immunohistochemistry

The molecular structures and the spin ground-state of the iron(ii/iii) complexes Fe1, Fe2 and Fe3, which contain dianionic macrocyclic [N4] ligands derived from substituted acetylacetaldehydes and 1,2-diamines, have been investigated by X-ray analysis and temperature-dependent susceptibility measurements, respectively. The iron(II) complexes FeII1 (which is dimeric by intermolecular coordination of one peripheral carbonyl group), FeII1MeOH, (FeIIL)2dabco (L = 1, 2, 3; dabco = 1,4-diazabicyclo[2.2.2]octane) and the iron(III) complex FeIII1Cl are pentacoordinate and have an intermediate-spin ground-state at room temperature (S = 1 for FeII; S = 3/2 for FeIII). The intermediate-spin state was confirmed by DFT-MO calculations for FeII1MeOH and FeIII1Cl and is also in agreement with the Mössbauer data of FeII1 and ESR measurements of FeIII1Cl. The iron centre in FeII2 is nearly square-planar and shows a strong decrease of the magnetic moment below T ≈ 250 K. This is probably due to an S = 0 to S = 1 spin-crossover or, more likely, to intermolecular antiferromagnetic interactions (shortest Fe–Fe distance of 3.4 Å). A new pair of octahedral iron(ii/iii) complexes with an N-heterocyclic axial ligand, FeII3(Py)2/[FeIII3(Py)2]PF6, could be crystallised. In contrast to the previously described pairs FeII1(Him)2/[FeIII1(Him)2]PF6 and FeII2Py2/[FeIII2Py2]ClO4, the orientation of the planes of the axial ligands is nearly independent of the oxidation step of the central atom. Octahedral derivatives with biologically relevant anions as axial ligands have been crystallised for the first time, namely [BzEt3N][FeIII1(NCS)2], [Et4N][FeIII2(CN)2](H2O)0.5, Na[FeIII2(NO2)2](MeOH)2(H2O)0.5 and [FeIII2(NO2)OH2](MeOH). The latter shows a magnetic moment of μeff ≈ 2.85 μB at room temperature, which decreases to 1.85 μB at lower temperature. This indicates an incomplete S = 1/2 to S = 3/2 spin-crossover, which is probably due to the presence of H2O as a weak axial ligand. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The Hekla eruption cloud on 26–27 February 2000 was the first volcanic cloud to be continuously and completely monitored advecting above Iceland, using the C-band weather radar near the Keflavík international airport. Real-time radar observations of the onset, advection, and waning of the eruption cloud were studied using time series of PPI (plan-position indicator) radar images, including VMI normal, Echotop, and Cappi level 2 displays. The reflectivity of the entire volcanic cloud ranges from 0 to >60 dBz. The eruption column above the vent is essentially characterised by VMI normal and Cappi level 2 values, >30 dBz, due to the dominant influence of lapilli and ash (tephra) on the overall reflected signal. The cloud generated by the column was advected downwind to the north-northeast. It is characterised by values between 0 and 30 dBz, and the persistence of these reflections likely result from continuing water condensation and freezing on ash particles. Echotop radar images of the eruption onset document a rapid ascent of the plume head with a mean velocity of ~30 to 50 m s -1, before it reached an altitude of ~11–12 km. The evolution of the reflected cloud was studied from the area change in pixels of its highly reflected portions, >30 dBz, and tied to recorded volcanic tremor amplitudes. The synchronous initial variation of both radar and seismic signals documents the abrupt increase in tephra emission and magma discharge rate from 18:20 to 19:00 UTC on 26 February. From 19:00 the >45 dBz and 30–45 dBz portions of the reflected cloud decrease and disappear at about 7 and 10.5 h, respectively, after the eruption began, indicating the end of the decaying explosive phase. The advection and extent of the reflected eruption cloud were compared with eyewitness accounts of tephra fall onset and the measured mass of tephra deposited on the ground during the first 12 h. Differences in the deposit map and volcanic cloud radar map are due to the fact that the greater part of the deposit originates by fallout off the column margins and from the base of the cloud followed by advection of falling particle in lower level winds.

Zusammenfassung: Ein Ausschalten des linken Herzohres (LHO) durch Resektion oder Verschließen ist eine verlockende Alternative zur oralen Antikoagulantien-Therapie, da über 90% der Thromben bei Vorhofflimmern im LHO entstehen. Dass das LHO nicht ein „unnützes Anhängsel“, sondern ein wichtiges Organ bei Tier und Mensch für die Aufrechterhaltung kardialer Regulationsmechanismen bei arterieller Hypertonie, Vorhofflimmern, koronarer Herzkrankheit, Herzklappenfehlern und Herzinsuffizienz ist, zeigen mehrere Studien. Eine Ausschaltung des LHO könnte das Durstgefühl bei Hypovolämie beeinträchtigen, die hämodynamische Antwort auf Volumen- oder Druckbelastung beeinträchtigen, die kardiale Auswurfleistung verringern und die Entwicklung einer Herzinsuffizienz begünstigen. Anstelle der Verhütung von Schlaganfällen könnte die Ausschaltung des LHO neue Risikofaktoren für die Entstehung von Schlaganfällen und Embolien erzeugen und damit den Patienten mehr schaden als nützen. Solange die physiologische und pathophysiologische Rolle des LHO beim Menschen nicht voll geklärt ist, sollte die Ausschaltung des LHO keine Alternative zur oralen Antikoagulantien-Therapie darstellen.

Hintergrund:Die therapeutische Anwendung von Ultraschall zur Rekanalisation eines akuten thrombotischen oder embolischen Gefäßverschlusses stellt eine vielversprechende Alternative bzw. Ergänzung existierender Therapieoptionen dar. Neuere Studien belegen eine thrombolytische Effizienz von Ultraschall in alleiniger Anwendung und in Kombination mit rr-PA. Ziel dieser Studie war es, zu untersuchen, ob sich durch Zugabe des Ultraschallkontrastmittels Levovist®eine Steigerung der ultraschallinduzierten Thrombolyse erreichen lässt. Material und Methoden:Untersucht wurde der thrombolytische Effekt von niederfrequentem (20,5 kHz) cw-(Continuous-Wave-)Ultraschall. In einzelnen Versuchsgruppen von je zehn bis 18 Thromben (Thrombusalter zwischen 3 und 6 h) wurde das Ausmaß der Thrombolyse mit und ohne Zugabe von rt-PA (3 μg/ml) und Levovist®(2 mg/ml) evaluiert. Das Ausmaß der Thrombolyse wurde über den Gewichtsverlust der einzelnen Thromben ermittelt. Die Experimente wurden in entgastem Natriumphosphatpuffer bei 37 °C und einer Flussrate von 15 ml/min in einem Flussmodell durchgeführt. Ergebnisse:Es zeigte sich ein signifikanter thrombolytischer Effekt bei alleiniger Anwendung von Ultraschall (41,8% Gewichtsverlust) im Vergleich zur Kontrollgruppe (24,2%). Die Zugabe von Levovist®während der Ultraschallexposition führte zu einer diskreten Steigerung des Effekts auf 44,7% (nicht signifikant). In Kombination von Ultraschall mit rt-PA fand sich jedoch eine signifikante Zunahme der Thrombolyse von 65,8% (ohne Levovist®) auf 74,2% nach zugabe von Levovist®(p < 0,05). Schlussfolgerung:Die Daten dieser Studie zeigen, dass sich die thrombolytische Effizienz von niederfrequentem Ultraschall in Kombination mit rt-PA durch die Zugabe von Levovist®steigern lässt. Background:Therapeutic application of ultrasound is a promising tool to develop an alternative or additional treatment modality of acute vessel occlusion. It has previously been shown that ultrasound enhances the effect of pharmacologic thrombolytic agents and has a thrombolytic potential in “stand-alone” therapy. The purpose of this study was to determine, whether the presence of the echo contrast agent Levovist™ further increases the thrombolytic efficacy of ultrasound. Material and Methods:Thrombolytic efficacy of low-frequency (20.5 kHz) continuous-wave ultrasound was evaluated. Fresh human blood clots (age 3–6 h) were sonicated for 10 min at an intensity of 0.35 W/cm2. The thrombolytic effect of ultrasound alone and in combination with rt-PA (3μg/ml) was assessed with and without addition of Levovist™ (2 mg/ml). Loss in weight of each blood clot was used to measure the extent of thrombolysis. The number of thrombi in each group was between ten and 18. Experiments were carried out in sodium phospate buffer, at a temperature of 37 °C, in a flow system with a flow rate of 15 ml/min. Results:The use of ultrasound alone showed a significant thrombolytic effect (41.8% weight loss), as compared to a control group (24.2%). The addition of Levovist™ further increased thrombolysis to 44.7%, which was not significant. However, in combination with rt-PA, ultrasound-mediated thrombolysis could be significantly increased from 65.8% to 74.2%, when Levovist™ was added (p < 0.05). Conclusion:These data show that the thrombolytic efficacy of low-frequency continuous-wave ultrasound in combination with rt-PA is augmented in the presence of Levovist™.

Material and Method:The force system delivered by the rectangular loop (R-loop) was the subject of this in-vitro investigation. The correction of a first-order irregularity was simulated in an inconsistent force system. Three types of R-loop made of 0.017"×0.025"TMA wire but differing in length and insertion system were tested in a 3D strain gauge (Hottinger™, Darmstadt, Germany). The buccal segment consisted of one molar and two bicuspids, with the first bicuspid as an active unit scheduled to be moved buccally into the dental arch. Results:The first R-loop tested revealed too high a force magnitude to be recommended for clinical use. A loop connecting only two teeth and bypassing the second premolar delivered a favorable initial force of 85 cN with a drop of 20 cN per 1 mm deactivation. In order to achieve a translatory tooth movement, a buccal root torque must be bent in addition into the short horizontal leg of the R-loop. The use of a transpalatal arch is indispensable if adverse side effects are to be avoided. Material und Methode:In einer In-vitro-Untersuchung wurde das Kraftsystem der R-Feder gemessen. Simuliert wurde die Korrektur von Fehlstellungen erster Ordnung. Die Prüfsituation entsprach einem inkonsistenten Kraftsystem. Drei in Drahtlänge und Art des Eingliederns sich unterscheidende R-Federn aus 0,017"×0,025"-TMA-Draht wurden in einer 3-D-Messapparatur (Fa. Hottinger™, Darmstadt) getestet. Das bukkale Segment bestand aus einem Molaren und zwei Prämolaren, wobei der erste Prämolar als aktive Einheit nach bukkal in den Zahnbogen bewegt werden sollte. Ergebnisse:Es zeigte sich, dass die als erste getestete R-Feder wegen ihrer zu großen Kraftabgabe nicht zum klinischen Einsatz gebracht werden kann. Günstig erwies sich die Feder, die unter Umgehung des zweiten Prämolaren, einer Zwei-Zahn-Beziehung entsprechend, den ersten Prämolaren und Molaren verband. Die nach bukkal gerichtete Kraft betrug dabei 85 cN mit einem Kraftabfall von 20 cN pro 1 mm Deaktivierung. Um eine translatorische Bewegung erzeugen zu können, muss zusätzlich ein bukkaler Wurzeltorque im kurzen horizontalen Schenkel der R-Feder eingebogen werden. Zur Vermeidung unerwünschter Nebenwirkungen ist die Verwendung eines Transpalatinalbogens unerlässlich.

We carried out a steady state kinetic analysis of the bacteriophage T4 DNA-[N6-adenine]methyltransferase (T4 Dam) mediated methyl group transfer reaction fromS-adenosyl-l-methionine (AdoMet) to Ade in the palindromic recognition sequence, GATC, of a 20-mer oligonucleotide duplex. Product inhibition patterns were consistent with a steady state-ordered bi-bi mechanism in which the order of substrate binding and product (methylated DNA, DNAMeandS-adenosyl-l-homocysteine, AdoHcy) release was AdoMet↓DNA↓DNAMe↑AdoHcy↑. A strong reduction in the rate of methylation was observed at high concentrations of the substrate 20-mer DNA duplex. In contrast, increasing substrate AdoMet concentration led to stimulation in the reaction rate with no evidence of saturation. We propose the following model. Free T4 Dam (initially in conformational form E) randomly interacts with substrates AdoMet and DNA to form a ternary T4 Dam-AdoMet-DNA complex in which T4 Dam has isomerized to conformational state F, which is specifically adapted for catalysis. After the chemical step of methyl group transfer from AdoMet to DNA, product DNAMedissociates relatively rapidly (koff= 1.7 s−1) from the complex. In contrast, dissociation of product AdoHcy proceeds relatively slowly (koff= 0.018 s−1), indicating that its release is the rate-limiting step, consistent withkcat= 0.015 s−1. After AdoHcy release, the enzyme remains in the F conformational form and is able to preferentially bind AdoMet (unlike form E, which randomly binds AdoMet and DNA), and the AdoMet-F binary complex then binds DNA to start another methylation cycle. We also propose an alternative pathway in which the release of AdoHcy is coordinated with the binding of AdoMet in a single concerted event, while T4 Dam remains in the isomerized form F. The resulting AdoMet-F binary complex then binds DNA, and another methylation reaction ensues. This route is preferred at high AdoMet concentrations.

As a part of an international project, initiated by the Ruhrgas AG, the massic heat capacity cpand the Joule–Thomson coefficient μJTwere measured with flow calorimeters. Great effort was made in the designing and construction of the equipment and in the experiments to reach a high accuracy of the results. The pressure range of the measurements was 0.5 MPa to 30 MPa and the temperature range 250 K to 350 K. The results are contained in the present paper. They yield the enthalpy as a function of temperature and pressure. Within the project they contribute to the experimental basis for a formulation of an equation of state.

Copper(II) complexes of tridentate dianionic β‐ketoenaminic ligands derived from differently functionalized amino‐deoxyglucoses were synthesized and characterized with respect to their structural, spectroscopic, and catalytic properties. The (probably dimeric) complex {1,2‐O‐isopropylidene‐6‐N‐(3‐acetyl‐2‐oxobut‐3‐enyl)amino‐6‐deoxyglucofuranoso}copper(II) Cu(3 a) was a highly efficient catalyst for the catechol‐oxidase‐like oxidation of 3,5‐di‐tert‐butylcatechol (dtbc) into 3,5‐di‐tert‐butylquinone (dtbq) by molecular oxygen (kcat=2.63 s−1). In contrast to this magnetically “normal” complex Cu(3 a), the analogous dinuclear complex [{Cu(2 a)}2], derived from the isomeric amino sugar 5‐amino‐5‐deoxyglucofuranose, forms six‐membered chelate rings with the sugar moiety and has very strong antiferromagnetic‐coupled copper atoms (resulting in a diamagnetic ground state). It has a rather insignificant activity (kcat<10−3s−1). The ligand H21 a, derived from a (protected) 6‐amino‐6‐deoxyglucopyranose, forms a trinuclear complex [{Cu(1 a)}2⋅Cu(OAc)2] in which two basic formula units are bridged by one copper acetate. This compound and the complex derived from an (isomeric) aminodeoxyglucopyranose ([Cu(4 a)]: kcat≈0.03 s−1) show moderate activity. All complexes with a peripheral ethoxycarbonyl group instead of the acetyl substituent R2, Cu(1 b)–Cu(3 b) and Cu(4 c), are inactive. The complexes derived from 2‐hydroxocyclohexylamine, Cu(5 a) and Cu(5 c), which were used as models of the active complex Cu(3 a), have the typical “cubane‐like” tetranuclear structure known from many copper complexes with derivatives of saturated 2‐aminoalcohols. They are inactive with respect to the activation of dioxygen.

Objective— The aim of this study was to evaluate if administration of adenosine during sinus rhythm to patients with PSVT of unknown mechanism is capable to detect dual AV nodal conduction and furthermore to evaluate this diagnostic parameter as a controlling test after slow pathway ablation in AVNRT.Methods and results— Before electrophysiological study 35 consecutive patients with PSVT were given adenosine during sinus rhythm. After radiofrequency ablation the adenosine test was repeated in a subset of 19 patients. The electrophysiological study revealed 19 patients (54%) with typical AVNRT (study group), 10 (29%) with atrioventricular reentry tachycardia (AVRT), 4 (11%) with ectopic atrial tachycardia (EAT) and 2 patients (6%) with inducible atrial flutter (AF) (control group). We observed a sudden increment of the PQ interval of more than 50 msec between two consecutive beats in 15 of 19 patients (79%) in the study group (75 ± 35 msec) and in 2 patients (1 with EAT, AF) of the control group (19 ± 12 msec) (p<0.001). After slow pathway radiofrequency ablation the sudden increment of PQ interval persisted in 4 of 12 patients (33%) of the study group. Three of these 4 patients had a relapse of AVNRT during a follow-up of 3 months.Conclusion— The administration of adenosine during sinus rhythm is an excellent noninvasive diagnostic test for identifying dual AV nodal conduction and additionally for verifying radiofrequency ablation results in patients with AVNRT.

Tibolone is a synthetic steroid with tissue-specific estrogenic, progestogenic, and androgenic properties. The drug relieves climacteric symptoms and prevents osteoporosis but does not stimulate the endometrium. We have previously shown that in laboratory animals tibolone inhibits the atherogenesis induced by a high-cholesterol diet. Therefore, we compared the antiatherosclerotic effect of oral tibolone at different dose levels with that of oral 17-estradiol (E2) and ethinyl estradiol (EE).

Analysis of whole genomes to monitor specific changes in gene activation or changes in gene copy number due to perturbation has recently become possible using DNA chip technologies. It is now becoming apparent, however, that knowing the genetic sequence encoding a protein is not sufficient to predict the size or biological nature of a protein. This can be particularly important in cancer research where posttranslational modifications of a protein can specifically lead to the disease. To address this area, several proteomic tools have been developed. Currently the most widely used proteomics tool is two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), which can display protein expression patterns to a high degree of resolution. However, 2D-PAGE can be time consuming; the analysis is complicated and, compared with DNA techniques, is not very sensitive. Although some of these problems can be alleviated by using high-quality homogeneous samples, such as those generated using microdissection techniques, the quantity of sample is often limited and may take several days to generate sufficient material for a single 2D-PAGE analysis. As an alternative to 2D-PAGE, a preliminary study using a new technique was used to generate protein expression patterns from either whole tissue extracts or microdissected material. Surface-enhanced laser desorption and ionization allows the retention of proteins on a solid-phase chromatographic surface or ProteinChip® Array with direct detection of retained proteins by time-of-flight mass spectrometry. Using this system, we analyzed tumor and normal tissue from head and neck cancer and microdissected melanoma to determine differentially expressed proteins. In particular, comparisons of the protein expression patterns from microdissected normal and tumor tissues indicated several differences, highlighting the importance of extremely defined tissue lysates for protein profiling.

Volcanic eruptions are events that rapidly and suddenly disperse gases and fine particles into the atmosphere, a process most conveniently studied from the synoptic satellite perspective, where remote sensing offers a practical tool for spatial and temporal measurements. Meteorological satellites offer approximately 20 years of archived data, which can be analysed for measurements of masses of SO2and fine volcanic ash in spatial two–dimensional arrays and integrated with other meteorological data. The satellite data offer a tool to study volcano–atmosphere interactions in a quantitative way. They provide information of unique value for understanding the fate and transport of fine silicates with significant health hazards and for addressing the problem of volcanic cloud hazards to jet aircraft. Studies of satellite data have demonstrated the following. (1) Volcanic clouds from convergent plate boundary volcanoes contain large and variable excesses of SO2.(2) The second day of atmospheric residence for volcanic clouds has significantly higher SO2than the first, suggesting that early volcanic H2S may be converting to SO2.(3) Complete conversion of SO2to sulphate in the stratosphere occurs at an efolding rate of approximately 120 days. SO2loss from stratospheric volcanic clouds occurs at an e–folding rate of approximately 35 days, and the SO2loss rate for volcanic clouds which only barely reach the stratosphere is rapid (efolding only a few days). The latter limits the stratospheric aerosol build–up from smaller eruptions.(4) Fine volcanic ash (with diameters of less than ca.25μm) in drifting volcanic clouds retrieved after 10 h or more appear to represent a small fraction (less than 2 of the total mass) of the total mass of magma erupted, and also a small fraction (less than 20) of the total mass of fine ash erupted. This is probably explained by the fact that the total mass is greatly reduced by aggregation processes within the volcanic cloud.(5) The amounts of fine ash decrease faster in volcanic clouds of larger eruptions, supporting the self–removal processes suggested by Pinto et al.in 1989.(6) Evidence for a strong role of ice in the fallout and aggregation of volcanic cloud ash is considerable.(7) In many cases, volcanic clouds separate into higher SO2–rich portions and lower ash–rich portions. The two portions follow different trajectories and the lower, ash–rich portions are affected by interactions with moist tropospheric air.

Epicardial structures are only rarely used for mapping and ablation of supraventricular and ventricular arrhythmias with the exception of WPW syndromes. However in a small percentage of patients obviously presenting an epicardial course of their arrhythmogenic structures, it may become necessary to seek out coronary veins and arteries in order to localize and eventually directly ablate the foci. Only single experiences are available in coronary vein mapping for ventricular tachycardias. In particular non-ischemic conditions like Chagas‘ disease, dilative cardiomyopathy and idiopathic left ventricular tachycardias tend to demonstrate an epicardial origin respectively breakthrough. By multipolar mapping using 2–3 French microcatheters with up to 16 poles, almost all coronary vein regions and arrhythmogenic foci can be reached respectively identified. In exceptional cases, microcatheter mapping may also be carried out in coronary arteries for localizing ventricular tachycardias for example due to remote myocardial infarction. Recently a direct approach to the epicardial space by transthoracic pericardial puncture has been introduced to perform a complete mapping of the epicardial surface not being limited by vascular structures. While coronary vein mapping can be considered a safe, reliable and helpful aid in identifying and localizing epicardial arrhythmogenic foci, the different ablative procedures still need to be evaluated and standardized with respect to safety and efficacy.¶   Multipolar basket mapping means an endocardial mapping procedure using a flexible basket consisting of up to 8 arms provided with multiple electrodes. After introducing the basket through a guiding catheter into the ventricle, the basket is distended and attached to the endocardium. An induced ventricular tachycardia may be mapped in seconds making this technique advantageous for nonsustained ventricular tachycardias. Initial results indicate basket mapping to be efficacious and relatively safe. At present, computer-based animation techniques are being evaluated for the transfer of the large amount of endocardial signal data registered into a three-dimensional coordinate system in order to guide the ablation catheter. Before basket mapping may be considered a clinically established tool, further developments and studies comparing basket with other mapping techniques are needed. Epikardiale Strukturen sind bislang wenig betretenes Gebiet, wenn es um Mapping oder Ablation tachykarder Herzrhythmusstörungen geht. Bei einem kleineren Teil von Patienten mit offensichtlich epikardialem Verlauf arrhythmogener Strukturen kann es jedoch notwendig werden, Koronarvenen oder -arterien aufzusuchen, um den Arrhythmiefokus zu lokalisieren und ggf. auch dort zu beseitigen. Bisher liegen nur Einzelerfahrungen zum Koronarvenen-Mapping bei ventrikulären Tachykardien vor. Insbesondere die nicht ischämischen Herzerkrankungen, z.B. die Chagas-Erkrankung, die dilatative Kardiomyopathie und idiopathische ventrikuläre Tachykardien, weisen nicht selten einen epikardialen Ursprung bzw. Durchbruch auf. Ein multipolares Mapping mit 2–3 French Mikrokathetern mit bis zu 16 Polen ermöglicht es, nahezu alle Koronarvenenabschnitte zu erreichen und den Arrhythmiefokus zu lokalisieren. In Ausnahmefällen kann auch ein Mikrokatheter-Mapping in Koronararterien durchgeführt werden, um die Lokalisation postinfarzieller ventrikulärer Tachykardien zu orten. Möglich ist auch ein direkter Zugang in den Epiperikardraum mittels transkutaner Perikardpunktion, um ein nicht durch anatomische Gefäßstrukturen limitiertes Mapping des gesamten Epikards durchführen zu können. Während das Koronarvenen-Mapping sicher, zuverlässig und aussagekräftig bei epikardial lokalisierten Arrhythmieherden durchgeführt werden kann, bedarf es für die verschiedenen ablativen Verfahren in epikardialen Strukturen noch weiterer Evaluierung hinsichtlich Sicherheit und Effizienz.¶   Das multipolare Basket-Mapping bedient sich eines flexiblen Körbchens bestehend aus bis zu 8 Armen, die mit multiplen Elektroden besetzt sind. Über einen Führungskatheter in den linken oder rechten Ventrikel eingeführt entfaltet sich das Körbchen und legt sich dem Endokard an. Nach Induktion der ventrikulären Tachykardien kann innerhalb weniger Sekunden die Lokalisation des Quellgebietes durchgeführt werden. Daher ist mit diesem Verfahren auch ein Mapping kurz dauernder ventrikulärer Tachykardien möglich. Erste Ergebnisse zeigen, dass das Basket-Mapping effektiv und relativ sicher ist. Derzeit sind computergestützte Animationsverfahren in Erprobung, um die Fülle der registrierten Signale in ein dreidimensionales Koordinatensystem zu transferieren, welches die topographische Steuerung des Ablationskatheters erleichtert.¶   Vor einer klinischen Etablierung sind weitere Entwicklungen und methodenvergleichende Untersuchungen erforderlich.

The catalytic oxidation of 2,4.6-tri-tert-butylphenol and 2,4,6-tri-tert-butylaniline with molecular oxygen and tert-butylhydroperoxide was investigated using biomimetic Mn-, Fe- and Co-complexes as catalysts. The catalytic activity and product distribution were determined and compared with those observed in the reactions of the well-known Co(salen) complex

AbstractThe high spin iron(II) chelate complex Fe1×2MeOHas well as its 1:1 derivative with TCNE have been investigated with respect to cooperative magnetic properties. Fe1×2MeOHrepresents a magnetic chain compound, wherein an intermolecular interaction via hydrogen bonds between the CH-groups of axially coordinated methanol and the ester groups located on the ligand periphery is observed. The weak spontaneous magnetization below approximately 10 K indicates cooperative magnetic behavior. The reaction of the iron(II) chelate complex with the electron acceptor TCNE leads to a 1:1 charge-transfer complex. The spontaneous magnetization occurs here below 10 K and is significantly higher compared to the magnetic iron(II) chelate chain compound.

AbstractA nonrandomized, prospective, interdisciplinary pilot study of 102 patients with noncompressive optic disc swelling with visual loss (ODSWVL) was performed in order to investigate etiologic and pathogenetic mechanisms. Forty-six patients suffered from underlying inflammatory disease. Seventeen patients suffered from highly probable cardiogenic embolization, 16 patients from multiple vascular risk factors. The remaining patients of the noninflammatory disease group suffered from leukemia, previously unknown or severely decompensated diabetes mellitus, acute arterial hypertension, different kinds of coagulopathies and others. Ninety-six of the 102 patients required medical treatment according to general medical standards. Inhomogeneity of the underlying disease processes explains the ineffectiveness of different monotherapies in previous studies. Interdisciplinary search for the underlying causes allows causative treatment. ODSWVL and anterior ischemic optic neuropathy in particular seem to be a common final pathway of various pathogenetic mechanisms due to different etiologies rather than a disease entity by itself.

Developments in transport, communications, and information technology now permit dramatic improvements in intercontinental transport time, cost, and quality of service. At the same time, shippers and consignees require reduction or elimination of inventories at all steps of the supply chain to improve their ability to effectively respond to changing economic and market conditions. A major challenge is the reduction of uncertainty and risks in total trans-ocean supply chains to permit more effective control of time, cost, and quality of service. Emphasis must, therefore, be placed on reducing deviations in time and cost of the different links in the chain. The use of conditional stochastic simulation to model, design, and control complex trans-ocean supply chains is described and advocated. It is shown that reducing link uncertainties can achieve large improvements in trans-ocean supply chain costs and profitability, and increase the market in an increasingly globalized world.

Summary The multicompartmental frog skin epidermis model proposed in a previous paper was applied to computer simulation studies on the kinetics of the wash-out process of Na* from frog skin. Both the kinetics of loading of the model membrane with Na* from the outside to reach steady-state conditions in all internal compartments, and of the wash-out process were followed. This was done for the case when two Na+ pumps were operative, or inoperative, simulating the inhibitory effect of ouabain on active Na+ transport in frog skin. The two pumps were characterized as transmembrane Na+ flow pumps, and internal Na+ maintenance pumps which contribute but little to net inward Na+ flux. The simulation results were in good agreement, both qualitatively and quantitatively, with data in the literature on the behavior of frog skin epidermis. This analysis gives support especially to the views held by Zerahn on location and size of the active Na+ transport pool in skin epithelium. Beyond this, however, this study clearly delineates the experimental conditions under which the estimation of the Na+ transport pool by the method of measuring the wash-out rate of Na* may be successful, and under which conditions this method will fail.

Summary The operation of the multicompartmental frog skin epidermal model 10E described in the preceding paper was tested to find out by computer simulation whether it responds to changes in [Na+] in the same manner as frog skin. In the range from 5 to 115mm [Na+]0, the rate of net Na+ flux across skin is known to increase. The results can be fitted to Michaelis-Menten's law of reaction kinetics, or, alternately, to Hoshiko's linear function, plotting fluxvs. log [Na+]0. Model 10E simulated the laboratory results on skin, provided that the rate coefficients at the site of entry of Na+ into the system were varied in exactly the same manner as they actually were found to vary in skin. In model studies, Na+ backflux (outflux) decreased with increasing [Na+]0, contrary to observations on skin. This discrepancy may be related to adaptive reactions in skins (decrease in permeability) when [Na+]0 is lowered, a feature that has not been modeled. It is known that the skin p.d. changes, mostly, by approximately 35 mV per decade change in [Na+]0. Model 10E gave very nearly the same result when the rate coefficients for entry of Na+ were changed as mentioned above (i.e., varied exactly as they were found to vary in skin). Skin and model 10E behaved similarly in that, at [Na+]0=[Na+]i=115mm, the extent to which labeling with Na* from the outside (12%) and from the inside (88%) is possible was the same. Model data are presented which show in which way the Na+ pools, [Na+] in the individual compartments, and intercompartmental fluxes changed with changing [Na+]0. Because of lack of experimental data on skin for comparison, these calculated results are purely hypothetical, but they are not unreasonable.

Summary The operation of a seven-compartment model is described with respect to flows of Na+ within and across this system, simulating published results obtained on frog skin. The seven compartments represent: one outside and one inside solution compartment; the subcorneal space; the first reacting cell layer (1. RCL); the remaining cell compartment; the non-, or slowly exchangeable Na+ compartment; the extracellular space. Assuming reasonable volumes for the epidermal compartments and further chosing, by trial and error, appropriate rate constants, a set of seven simultaneous linear differential equations was solved by the application of the Continuous System Modeling Program (CSMP), using an IBM 1130 computer. Initial conditions for influx, backflux and net flux were taken which correspond to [Na+]0; [Na+]i=115mm. Print-out data were obtained at 0.5-min intervals for 30 min, when steady states were obtained in 13 models studied, varying certaink's thus simulating actions of chemical agents (hormones; drugs). Simulation was achieved with regard to rate of influx, backflux and net flux, steady-state time (30 min), and electrical potentials. In addition, this approach gave detailed information on Na+ pool sizes and their variations with changes ink's. These results are compared to published data on frog skin and good agreement between operation of skin epidermis and model was found.

A patient is described whose oral speech consists exclusively of repetitively used stereotypical utterances (speech automatisms) but whose written performance is far better preserved. Written language investigation revealed that his phonological route for writing was not totally blocked. In writing to dictation, word length and syllabic structure were largely respected, even for nonwords. Picture-matching tasks which manipulated phonological similarity demonstrated relatively preserved access to lexical phonology. A nonlexical and sub-phonemic hypothesis of automatism-generation is proposed.

The massic heat capacitycp=(∂h/∂T)pof 1,2,2,2-tetrafluoroethane (refrigerant R134a) was measured at 18 temperatures from 253 K to 523 K at pressures between 40 kPa and 30 MPa. The Joule–Thomson coefficient μJT=(∂T/∂p)hof this substance was measured at six temperatures from 333 K to 423 K at pressures up to 20 MPa. The R134a has no ozone depletion potential. Its global warming potential is about one-tenth of that of the refrigerant R115 (C2F5Cl) for which it can be a substitute as a working fluid in energy technologies.

Hysteroscopy was performed on 75 patients undergoing a dilatation and curettage for routine gynecologic problems. For the distention of the uterine cavity carbon dioxide was used and found to be an adequate medium to establish a pneumometra. It provided good visualization and was simple and safe to use for the hysteroscopic examination. Arterial blood-gas determinations revealed no change in the PO2, PCO2) and pH with carbon dioxide insufflation. There were no complications in this series. The advantages and applications of carbon dioxide hysteroscopy are outlined.

Abstract: In the present paper some typical gas laser construction and their performances will be described. Aspects of transition selective systems and high pressure operation will be treated.