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Vergleichende biomechanische Studie zur Primärstabilität der geraden vs. v-förmigen minimalinvasiven Osteotomie am Kalkaneus
No full textDie vorliegende Dissertation untersucht vergleichend die Primärstabilität gerader versus v-förmiger minimalinvasiver Kalkaneusosteotomien. An 18 humanen fresh-frozen Präparaten wurden beide Techniken biomechanisch getestet. Die Auswertung umfasste zwei Messzyklen mit einer zyklischen Belastungen bis 600 N mit Analyse von Steifigkeit, Versagensraten und Dislokationen. Während sich im ersten Messzyklus keine signifikanten Unterschiede zeigten, deuteten im zweiten Zyklus höhere mittlere Steifigkeiten sowie geringere Dislokationsraten auf eine tendenzielle Überlegenheit der V-Osteotomie hin. Statistisch konnte jedoch keine signifikante Überlegenheit nachgewiesen werden. Die Ergebnisse weisen auf das Potenzial der V-förmigen Technik für eine stabilere postoperative Situation hin
Numerical analysis of local thermal non-equilibrium experiments reveals conceptual regimes of grain-scale heat transport
No full textModeling heat transport in saturated porous media typically assumes local thermal equilibrium
(LTE) conditions, though this assumption lacks justification. Recent work has revealed local thermal nonequilibrium
(LTNE) effects for groundwater flow conditions, which standard one‐dimensional analytical and
numerical models fail to capture accurately. In this study, we develop and validate a 2D numerical model for
two‐phase heat transport at the granular scale to describe experimental LTNE effects previously observed, by
coupling heat fluxes in both phases with a heat transfer term. Our results show that LTNE and non‐uniform flow
effects are superimposed and challenging to disentangle. However, the experimental results, expressed as
temperature difference between solid and fluid phase (ΔT(t)), best match the case where the heat transfer
coefficient hsf → ∞(maximal efficiency), showing that hsf is insensitive for flow rates of 3–23m d 1 and grain
sizes of 5–30 mm. The model further confirms that different and negative ΔT(t) for same grain sizes are caused
by non‐uniform flow where arrival of the thermal front varies at the grain scale. Overall, our findings reveal
multiple different heat transport concepts: (a) LTE, which is widely used; (b) Baseline LTNE, arises from
different thermal properties between phases; (c) Phase transfer LTNE, which involves a limited heat transfer
rate between phases; (d) Non‐uniform flow LTNE, which is caused by pore‐scale flow variations. This detailed
concept of LTNE effects suggests that interphase heat transfer plays a negligible role toward LTNE effects at the
granular scale under conditions relevant for hydrogeology
Editorial : Bacteriophage therapy in orthopedics : key questions and emerging answers
No full textMusculoskeletal infections remain among the most challenging conditions in orthopaedic practice, often requiring prolonged antibiotic therapy, repeated surgical interventions, and extensive rehabilitation. The emergence of antimicrobial resistance and the persistence of bacterial biofilms further complicate management, particularly in chronic osteomyelitis, infected fracture fixations, and periprosthetic joint infections. In this context, bacteriophage therapy has re-emerged as a promising adjunctive strategy. Bacteriophages offer targeted antibacterial activity, including the ability to disrupt biofilms and self-replicate at the site of infection. Contemporary approaches, such as phagograms, customised phage cocktails, and local delivery techniques, have addressed many historical limitations related to phage specificity and accessibility. A growing number of case reports and small clinical series have documented successful applications of phage therapy in orthopaedic infections, with encouraging safety profiles and infection resolution in refractory cases. Early-phase clinical trials are now systematically evaluating the feasibility, pharmacokinetics, and immunogenicity of phage therapy in musculoskeletal settings. Furthermore, synergistic effects with antibiotics and the potential to overcome biofilm-related antibiotic tolerance highlight the added therapeutic value of this approach. While regulatory and manufacturing challenges persist, the integration of bacteriophages into multidisciplinary orthopaedic care marks a paradigm shift toward precision microbiology. Rather than replacing conventional treatment, phage therapy complements surgery and antibiotics, offering a biologically rational and patient-specific adjunct in the fight against recalcitrant infections
MLUH-E-297_1, Elanoides forficatus forficatus (Linnaeus, 1758), eggshell
No full textInventory No.: MLUH-E-297_1, Object: eggshell, Species: Elanoides forficatus forficatus (Linnaeus, 1758), Preservation: complete preservation, Locality_loc.: Black Hawk County, Locality today: Iowa, Country: USACollector_leg.: J. A. Singlar, Date: 25/05/1894, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 154, Identification by: M. Schönwetter, Aquisition: 1935, Aquired from: C. H. Gowland, ex Collection: e. Coll. Stephens Auction; ex. Coll. J. A. Sinclair; ex. Coll. C. H. Gowland, Additional Information: Schönwetter wrote down Black Hawk county Texas the auction house label just says Black Hawk County. There is no so called county in Texas. Schönwetter probably just added that without researc
Investigation of integrated crystallization methods for the biocatalytic preparation of pharmaceutically relevant compounds and fine chemicals
No full textThroughout the last three decades, the transition towards a sustainable and “green” approach to chemistry has been set as a future goal for many states and industrial players. In pursuit of this goal, the research on enzymes as biocatalysts and on enzymatically driven synthesis of industrially relevant compounds has intensified. During that time, first industrial-scale applications containing enzymatic reaction steps have been adopted by pharmaceutical and agrochemical manufacturers. Enzymatic catalysis possesses many advantages compared to conventional organic chemistry synthesis pathways, yet it also has its drawbacks, which often prevents enzymes from replacing their conventional counterparts in the manufacturing process.
Nevertheless, some of those drawbacks, like product inhibitions and unfavorable reaction equilibria, can be circumvented by reaction engineering towards combining the reaction with a simultaneous separation process, removing the product to another phase. This process is called in situ product removal (ISPR). This work investigates ISPR approaches based on product removal to the solid phase, namely reactive crystallization, focusing on their application for the (chemo)enzymatic synthesis of the compound classes of chiral amines and chiral carboxylic acids. In the first part, a previously developed concept for the reactive crystallization of chiral amines from transaminase-catalyzed reactions i1s reverted to a simple downstream processing concept to test its selectivity towards the high molecular weight amino products compared to low molecular weight amino donors. A model compound 1s crystallized selectively as an ammonium-carboxylate salt with very high purity and high yield recovered from the reaction mixtures. In the process, this crystallization technique 1s further adopted for another class of enzymatic reaction systems (amine dehydrogenases), broadening the application field for this separation method to other enzymatic methods of amine synthesis. The selectivity of this product crystallization system 1s tested under duress with varying crystallization parameters and surpluses of low molecular weight amino donors, showing robustness and reproducibility of high purities and yields of the crystallized amino product salts. In the second part of this work, the amine product salt crystallization concept, previously developed for reactive crystallization of primary a-chiral amines, is adopted for the transaminase-catalyzed synthesis of [-chiral amines. As a representative B-chiral amine model compound, (R)-B-methylphenethylamine 1s chosen. A dynamic kinetic resolution of its precursor, 2-phenylpropanal, 1s performed, using a highly stereoselective transaminase as the enzymatic catalyst. Reactions, which are augmented by the described reactive amine product salt crystallization concept, show much higher yields, than the controls without reactive crystallization, reaching productivities of 16 g/(1-d) on preparative scale. Therefore, in the second part of this work, the concept for continuous reactive crystallization of amino product salts from transaminase-catalyzed reactions 1s proven to be applicable in the synthesis of -chiral amines, a compound class represented among important pharmaceuticals. In the third part of this work, a novel reactive crystallization concept is established for the (chemo)enzymatic dynamic kinetic resolution of chiral racemic compounds. On the basis of mandelic acid as a model substrate, enzymatically driven racemization (via a mandelate racemase) was successfully combined with diastereomeric salt crystallization. The resolution of the racemic mandelic acid towards (R)-mandelic acid was achieved via diastereomeric salt crystallization with an enantiopure ammonium counterion. On preparative scale, the developed concept led to yields of up to 60 % (based on the total amount of the racemate) and a very high enantiomeric excess of 95 % for the isolated mandelic acid enantiomer, underlining the enantioselectivity of the crystallization. Remarkably, this concept was realized in an aqueous medium, although the initial solubility of mandelic acid in water is fairly high (1 M).Literaturangabe
Inference for meaningful estimands in factorial survival designs and competing risks settings
No full textEstimands are highly used in survival analysis, e.g., to compare the effects of different treatments in a clinical study. Beyond the popular hazard ratio, which relies on the rather restrictive proportional hazards assumption, there are various estimands that do not rely on this assumption as, for example, the Mann-Whitney effect and the restricted mean survival time. Several inference procedures for estimands in simple one- and two-sample survival problems have already been developed in the literature. However, since the underlying designs of real data are often more complex, there is a lack of adequate testing procedures in more complex survival models. Moreover, ties easily occur in real data if time is measured in whole days, months, or years. While many existing methods require continuous survival distributions, we prove all methods without any continuity assumption on the survival and censoring times by empirical process theory. Thus, we explicitly allow for ties in the data. Furthermore, in many practical applications, not only one hypothesis is of interest, e.g., if not only the existence of an effect of any treatment is of interest but also which treatment groups have a different effect. In this case, multiple tests need to be performed to infer several hypotheses simultaneously.
To close all above-mentioned gaps, we construct tests for a version of the Mann-Whitney effect and restricted mean survival times in the paired survival setup, multiple tests for restricted mean survival times in general factorial designs, and multiple tests for restricted mean time losts of competing risks in general factorial designs. For the multiple tests, we incorporate the multivariate limit distribution of the test statistics to gain more power in contrast to a simple Bonferroni-correction. Additionally, we apply different resampling procedures, as permutation and bootstrap approaches, for all tests to improve the small sample performance of the tests. Moreover, for proving the validity of the resampling tests, we design a flexible conditional delta-method for resampling empirical processes.Estimands werden in der Überlebenszeitanalyse häufig verwendet, z.B. um die Auswirkungen verschiedener Behandlungen in einer klinischen Studie zu vergleichen. Neben dem weit verbreiteten Hazard Ratio, das auf der eher restriktiven Proportional-Hazard-Annahme beruht, gibt es verschiedene Estimands, die nicht auf dieser Annahme beruhen, wie z.B. der Mann-Whitney-Effekt und die ’restricted mean survival time’. In der Literatur wurden bereits mehrere Inferenzverfahren für Estimands bei einfachen Ein- oder Zwei-Stichproben-Problemen entwickelt. Da die den realen Daten zugrunde liegenden Designs jedoch häufig komplexer sind, fehlt es an geeigneten Testverfahren für komplexere Überlebenszeitmodelle. Außerdem treten bei realen Daten Bindungen auf, wenn die Zeit in ganzen Tagen, Monaten oder Jahren gemessen wird. Während viele bereits existierende Methoden stetige Überlebenszeitverteilungen voraussetzen, beweisen wir alle Methoden ohne Stetigkeitsannahme für die Überlebens- und Zensierungszeiten durch empirische Prozesstheorie. Somit erlauben wir Bindungen in den Daten explizit. Außerdem ist in vielen praktischen Anwendungen nicht nur eine Hypothese von Interesse, z.B. wenn nicht nur die Existenz eines Effekts einer Behandlung von Interesse ist, sondern auch, welche Behandlungsgruppen einen unterschiedlichen Effekt haben. In diesem Fall müssen multiple Tests durchgeführt werden, um mehrere Hypothesen simultan testen zu können.
Um alle oben erwähnten Lücken zu schließen, konstruieren wir Tests für eine Version des Mann-Whitney-Effekts und ’restricted mean survival times’ für gepaarte Überlebenszeiten, multiple Tests für ’restricted mean survival times’ in allgemeinen faktoriellen Designs und multiple Tests für ’restricted mean time losts’ von konkurrierenden Risiken in allgemeinen faktoriellen Designs. Bei den multiplen Tests beziehen wir die multivariate Grenzverteilung der Teststatistiken ein, um im Gegensatz zu einer einfachen Bonferroni-Korrektur eine höhere Güte zu erzielen. Darüber hinaus wenden wir für alle Tests verschiedene Resampling-Verfahren an, wie Permutation und Bootstrap-Ansätze, um die Performance der Tests bei kleinen Stichprobenumfängen zu verbessern. Um die Gültigkeit der Resampling-Tests zu beweisen, entwickeln wir außerdem eine flexible bedingte Delta-Methode für Resampling bei empirischen Prozessen.Literaturverzeichnis: Seite 71-7
MLUH-E-106_5, Falco tinnunculus Linnaeus, 1758, eggshell
No full textInventory No.: MLUH-E-106_5, Object: eggshell, Species: Falco tinnunculus Linnaeus, 1758, Preservation: medium damage, Locality_loc.: Neuroda, Locality today: Neuroda, Country: GermanyDate: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 192, Identification by: M. Schönwetter, Aquisition: 1905, Aquired from: M. Schönwette
MLUH-E-388_1, Milvus migrans (Boddaert, 1783), eggshell
No full textInventory No.: MLUH-E-388_1, Object: eggshell, Species: Milvus migrans (Boddaert, 1783), Preservation: complete preservation, Locality_loc.: Futtegurh Indien, Locality today: India, Country: IndiaDate: 19/02/1872, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 156, Identification by: M. Schönwetter, Aquisition: 1910, Aquired from: Dr. Rey, ex Collection: ex.Coll. Dr. Re
Addition of two new genera : Marcstadlera gen. nov. and Neoclypeosphaerella gen. nov. (Mycosphaerellaceae) : based on polyphasic evidence
No full textDuring a survey of foliicolous fungi in India, two interesting anamorphic hyphomycetous fungal specimens were collected from infected leaves of Calotropis spp. and Mallotus philippensis. Calotropis spp. produce fascicles of conidiophores from stromata, accompanied by secondary superficial hyphae bearing solitary conidiophores. The specimen on Mallotus philippensis resembled Mycovellosiella, characterized by secondary superficial hyphae bearing micronematous to semi-macronematous, mononematous, unbranched, and aseptate conidiophores. A polyphasic approach—including morphological, cultural, and multilocus phylogenetic analyses (LSU-Rpb2-ITS), coupled with genealogical concordance phylogenetic species recognition—identified its relationship with cercosporoid fungi within the family Mycosphaerellaceae. The analysis confirmed that these fungal specimens represent distinct lineages without known morphological or DNA sequence counterparts. Consequently, two new genera are proposed: Marcstadlera and Neoclypeosphaerella, with M. malloti comb. nov. and N. calotropidis comb. nov. as their respective type species. Additionally, Clypeosphaerella calotropidis, Clypeosphaerella quasiparkii, and Pseudocercospora malloti are recognized as new synonyms. Several genera in the Mycosphaerellaceae, including Marcstadlera and Neoclypeosphaerella, are monophyletic. The ultrastructure of the conidiogenous loci and hila differs between these two genera. In Marcstadlera, the loci are cylindrical or peg-like, truncate at the apex, while the conidial base is narrowly obconically truncate. In Neoclypeosphaerella, the loci are slightly protuberant and surrounded by a circular rim-like structure, forming a truncated apex with a centrally positioned small apical depression. The conidial base is obconically truncated and also surrounded by a circular rim-like structure
MLUH-E-407_1, Pernis apivorus (Linnaeus, 1758), eggshell
No full textInventory No.: MLUH-E-407_1, Object: eggshell, Species: Pernis apivorus (Linnaeus, 1758), Preservation: complete preservation, Locality_loc.: Anhalt, Locality today: Saxony-Anhalt, Country: GermanyDate: 29/05/1930, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 155, Identification by: M. Schönwetter, Aquisition: 1936, Aquired from: O. Salzman, ex Collection: ex. Coll. O. Salzma