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MLUH-E-259_2, Buteo hemilasius Temminck and Schlegel, 1845, eggshell
No full textInventory No.: MLUH-E-259_2, Object: eggshell, Species: Buteo hemilasius Temminck and Schlegel, 1845, Preservation: complete preservation, Locality_loc.: Sidemi Amur, Locality today: Primorsky Krai, Country: RussiaDate: ?, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 164, Identification by: M. Schönwetter, Aquisition: 1939, Aquired from: Schl., ex Collection: ex. Coll. Schl; ex. Coll. Tancr
Cytochrome P450-induced backbone rearrangements in terpene biosynthesis of plants
No full textTerpenes, the largest class of plant specialized products, are built from C5 building blocks via terpene synthases and oxidized by cytochrome P450 enzymes (CYPs) for structural diversity. In some cases, CYPs do not simply oxidize the terpene backbone, but induce backbone rearrangements, methyl group shifts, and carbon–carbon (C–C) scissions. Some of these reactions were characterized over 25 years ago, but most of them were reported in recent years, indicating a highly dynamic research area. These reactions are involved in mono-, sesqui-, di- and triterpene metabolism and provide key catalytic steps in the biosynthesis of plant hormones, volatiles, and defense compounds. Many commercially relevant terpenoids require such reaction steps in their biosynthesis such as triptonide (rodent pest management), secoiridoids (flavor determinants), as well as ginkgolides, cardenolides, and sesquiterpene lactones with pharmaceutical potential. Here, we provide a comprehensive overview of the underlying mechanisms
Symmetric and non-symmetric cone separation via Bishop-Phelps cones in normed spaces
No full textIn this paper, we study relationships between symmetric and non-symmetric separation of (not necessarily convex) cones by using separating cones of Bishop-Phelps type in real normed spaces. Besides extending some known results for the non-symmetric cone separation approach, we propose a new symmetric cone separation approach and establish cone separation results for it by using some cone separation results obtained for the non-symmetric cone separation approach twice (by swapping the roles of the cones). In addition to specifically emphasizing the results for the convex case, we also present some existence results for (bounded) convex bases of convex cones. Finally, we highlight some applications of symmetric and non-symmetric cone separation in optimization
The effects of weather extremes on wheat prices in Russia : rhe role of inputs and Russia’s war in Ukraine
No full textUtilizing the normalized difference vegetation index (NDVI) in the error correction model, we examine the effects of weather anomalies on wheat prices in six wheat-producing regions in Russia. Our analysis reveals that weather-induced price effects are most pronounced in regions most distant from the world market, particularly those primarily producing spring wheat for domestic consumption. These findings are corroborated by a model that incorporates precipitation data and partially supported by a model that uses maximum temperature as an alternative measure for weather extremes. The absence of significant weather impacts on wheat prices in the exporting North Caucasus region likely reflects the region’s advanced production systems and modern management practices. Since Russia’s invasion of Ukraine, the profitability of wheat production for Russian farmers has declined substantially, leading to reduced use of agricultural inputs. If this trend of low input application continues, weather fluctuations could have a more pronounced impact on wheat prices
Exploring antiemetic strategies in hematologic malignancies : a comprehensive literature review and evaluation of antiemetic efficacy in patients receiving high-dose chemotherapy prior to hematopoietic stem cell transplantation
No full textPurpose:
Most antiemetic studies have been conducted in patients with solid tumors receiving single-dose chemotherapy. A research gap leaves healthcare providers without clear guidance on effective antiemetic regimens and schedules for patients with hematologic malignancies undergoing high-dose multiday chemotherapy. This literature search identified antiemetic studies and assessed efficacy outcomes in the hematology setting, and specifically in patients receiving high-dose chemotherapy prior to hematopoietic stem cell transplantation (HSCT).
Methods:
A literature review of both PubMed and Embase was performed for published studies evaluating antiemetic regimens including an NK1 receptor antagonist (RA) and/or a 5HT-3RA with/without dexamethasone in the hematology setting. Key features of all studies are reviewed, and antiemetic efficacy is summarized specifically for studies in which patients received high-dose chemotherapy prior to HSCT.
Results:
Twenty-two of an initial 926 identified publications met the predefined inclusion criteria. The studies were heterogenous, with varying characteristics pertaining to randomization, control groups, size, cancer types, chemotherapies, antiemetics, and assessments, making cross-study comparisons and conclusions difficult. The range of response rates was wide with numerous studies showing complete response, no emesis or no nausea rates of less than 50%. Response rates were highest when an NK1 RA regimen was administered; however, an NK1 RA was underutilized and only administered in two-thirds of the studies.
Conclusion:
The results reflect a significant clinical problem in preventing chemotherapy-induced nausea and vomiting (CINV) in patients with hematologic malignancies. The scarcity and heterogeneity of studies highlight challenges inherent in this area. This underscores a pressing need for rigorous randomized trials in hematology and HSCT assessing treatment-related CINV and effectiveness of antiemetic regimens
An experimental parametric analysis of particle dampers for optimizing their applications
No full textParticle damping is a passive vibration mitigation technique that harnesses the inherent dissipative properties of granular materials. By strategically incorporating these materials into vibrating structures, significant energy dissipation can be achieved through particle-particle and particle-wall collisions.
However, the complex interactions between particle properties, cavity geometry, packing arrangement, and excitation conditions have made it difficult to develop a comprehensive design framework. This work addresses these challenges through extensive experimental investigations, identifying key design parameters and their effects on vibration reduction, ultimately establishing a robust framework for optimizing particle damper performance.
Advancements in particle damping are presented, focusing on overcoming the limitations of conventional particle dampers made from traditional granular materials (e.g. steel and lead). While these dampers effectively reduce vibration amplitudes in high-frequency ranges, their performance at low frequencies is often limited. A significant contribution of this thesis is the development of recycled rubber particle dampers (RRPDs) made from automotive tire waste. These dampers not only reduce vibrations across both high- and low-frequency ranges but also minimize additional mass, making them suitable for the
lightweight industry. Additionally, this study examines the impact of polydisperse granular materials on vibration attenuation, an area underexplored in previous studies. The findings indicate that both particle size and particle size distribution are critical to optimizing damper efficiency.
Another significant challenge in the field of particle damping is the inadequate kinetic energy generated by the main structure, which often fails to mobilize the granular particles within the damper. Without sufficient kinetic energy, the granular materials cannot effectively interact through particle-particle and particle-wall collisions, limiting the overall damping performance. To overcome this issue, three innovative passive design variants are introduced in this thesis, namely: the thin wall cavity (TWC), the
thin wall cavity with additional sheets (TWC-AS), and the ring cavity (RC). These designs effectively introduce additional kinetic energy into the granular materials, enhancing their mobilization and improving damping performance.
The long-term reliability of particle dampers, particularly under prolonged loading conditions, has remained largely unexplored. To address this, an extensive durability test was conducted to evaluate the performance of dampers incorporating rubber granulates under high-amplitude cyclic loading and varying temperature conditions over an extended period. The results showed that, even after prolonged exposure to these challenging conditions, the dampers retained their vibration attenuation capabilities.
This demonstrates that rubber granulate-based particle dampers are not only effective in the short term but are also capable of sustaining performance under long-term loading conditions, making them a promising solution for real-world engineering applications.
Lastly, this work bridges the gap between laboratory research and industrial applications by testing the examined design parameters on full-scale structures, such as wind turbine generators, blades, and electric vehicles. The results show that particle dampers, designed according to the proposed framework, can be effectively implemented in large-scale engineering systems.
This thesis provides valuable new insights and introduces innovative advancements in particle damping technology. These developments enhance the efficiency and durability of particle dampers, addressing key limitations and optimizing their performance. Furthermore, the research offers practical and effective solutions for applying particle damping in industrial-scale structures, demonstrating its efficiency in improving the performance and reliability of engineering systems in real-world applications. Through
these contributions, this work significantly advances both the theoretical understanding and practical implementation of particle damping technology.Partikeldämpfer stellen ein passives Verfahren zur Reduktion mechanischer Schwingungen dar, dessen Wirkprinzip auf den dissipativen Eigenschaften granularer Materialien beruht. Durch die gezielte Integration dieser Materialien in schwingungsbeanspruchte Strukturen erfolgt eine effiziente Energiedissipation infolge von Partikel-Partikel- sowie Partikel-Wand-Kollisionen. Die Entwicklung eines übertragbaren und umfassenden Gestaltungsansatzes für Partikeldämpfer wird jedoch durch die komplexen Wechselwirkungen zwischen partikelbezogenen Materialeigenschaften, Kavitätsgeometrie, Packungsdichte und den jeweiligen Anregungsbedingungen erheblich erschwert. Die vorliegende Arbeit setzt sich mit diesen Herausforderungen auseinander, indem sie auf systematische experimentelle Untersuchungen zurückgreift, zentrale Einflussparameter sowie deren Wirkung auf
die Schwingungsdämpfung herausarbeitet und auf dieser Grundlage ein robustes Optimierungskonzept für die Auslegung von Partikeldämpfern entwickelt.
Aufbauend auf diesen Grundlagen werden im weiteren Verlauf neue Entwicklungen im Bereich der Partikeldämpfer vorgestellt, die darauf abzielen, die Beschränkungen konventioneller Dämpfungskonzepte zu überwinden.
Während herkömmliche Partikeldämpfer zwar eine wirksame Reduktion von Schwingungsamplituden im Hochfrequenzbereich ermöglichen, zeigen sich oftmals Defizite hinsichtlich der Dämpfung im Niederfrequenzbereich.
Ein wesentlicher Beitrag dieser Arbeit liegt daher in der Entwicklung gummibasierter Partikeldämpfer (Recycled Rubber Particle Dampers, RRPDs), die aus Altreifenmaterial gefertigt werden. Diese Dämpfer erlauben eine effiziente Schwingungsreduktion sowohl im Hoch- als auch im Niederfrequenzbereich, wobei die zusätzliche Masse gering bleibt – ein entscheidender Vorteil für Leichtbauanwendungen. Ergänzend erfolgt eine Analyse des Einflusses polydisperser granularer Materialien auf die Schwingungsdämpfung, einem bislang nur unzureichend adressierten Forschungsaspekt. Die erzielten Ergebnisse verdeutlichen, dass sowohl die absolute Partikelgröße als auch die Partikelgrößenverteilung maßgebliche Parameter für die Optimierung der Leistungsfähigkeit von Partikeldämpfern darstellen.
Darüber hinaus wird eine weitere zentrale Herausforderung adressiert, die in der begrenzten Mobilisierung granularer Partikel liegt. Diese tritt infolge einer unzureichenden kinetischen Energie der Hauptstruktur auf und reduziert die Effizienz der Schwingungsdämpfung. Zur Lösung dieses Problems werden drei innovative passive Konstruktionskonzepte vorgestellt: die Dünnwandkavität (Thin-Walled Cavity, TWC), die Dünnwandkavität mit zusätzlichen Platten (TWC with Additional Sheets, TWC-AS) sowie die Ringkavität (Ring Cavity, RC). Diese Ansätze verbessern die Energieübertragung auf die Partikel, intensivieren deren Bewegung und steigern dadurch die Dämpfungsleistung signifikant.
Ein weiterer Schwerpunkt dieser Arbeit liegt auf der Untersuchung der langfristigen Zuverlässigkeit von Partikeldämpfern, die bislang nur unzureichend erforscht ist. Zu diesem Zweck wurde ein umfangreicher Dauertest durchgeführt, bei dem die Leistungsfähigkeit gummigranulatbasierter Partikeldämpfer unter zyklischen Hochamplitudenbelastungen sowie variierenden Temperaturbedingungen über einen längeren Zeitraum systematisch bewertet wurde. Die Ergebnisse zeigen, dass die untersuchten Dämpfer auch nach langandauernder Beanspruchung ihre schwingungsdämpfenden Eigenschaften beibehalten. Damit wird nachgewiesen, dass Partikeldämpfer auf Basis von Gummigranulat nicht nur kurzfristig wirksam sind, sondern auch unter Langzeitbelastung eine stabile Leistungsfähigkeit aufweisen und sich somit als besonders vielversprechende Lösung für ingenieurtechnische Anwendungen qualifizieren.
Abschließend wird eine Brücke zwischen laborbasierten Untersuchungen und industriellen Anwendungen geschlagen, indem die identifizierten Designparameter an großtechnischen Strukturen wie Windturbinen-Generatoren, Rotorblättern und Elektrofahrzeugen evaluiert werden. Die Ergebnisse belegen, dass Partikeldämpfer, die auf Grundlage des entwickelten Designrahmens konzipiert wurden, erfolgreich in großskaligen ingenieurtechnischen Systemen implementierbar sind.
Zusammenfassend generiert diese Dissertation neue wissenschaftliche Erkenntnisse sowie innovative Konzepte zur Weiterentwicklung der Partikeldämpfertechnologie. Die erzielten Resultate leisten einen Beitrag zur Steigerung der Effizienz und Langlebigkeit von Partikeldämpfern, indem bestehende Beschränkungen gezielt adressiert und die Leistungsparameter systematisch optimiert werden. Darüber hinaus werden praxisorientierte Lösungsansätze für den industriellen Einsatz bereitgestellt, welche die Effektivität der Partikeldämpfung zur Erhöhung der Leistungsfähigkeit und Zuverlässigkeit technischer Systeme in realen Anwendungen nachweisen. Damit erbringt die vorliegende Arbeit einen substantiellen Beitrag sowohl zur theoretischen Fundierung als auch zur praktischen Implementierung der Partikeldämpfertechnologie.Literaturverzeichnis: Blatt 200-21
Escherichia coli FocA/B-dependent H+ and K+ fluxes : influence of exogenous versus endogenous formate
No full textEscherichia coli translocates formate/formic acid bidirectionally across the cytoplasmic membrane by the FocA/FocB formate channels during fermentation. Depending on the pH and whether formate is supplied exogenously or generated internally, the mechanisms of translocation differ. This study elucidates the role of these channels in dependence on FOF1 ATPase activity in stationary phase cells after cultivation by mixed-carbon fermentation at pH 7.5. In cells cultivated with glucose plus glycerol, exogenously added formate increased the N,N′-dicyclohexylcarbodiimide (DCCD)-sensitive (FOF1 ATPase-dependent) proton flux in single or double foc mutants. Moreover, exogenously supplied formate also increased the DCCD-sensitive potassium flux, but only in mutants where focB was absent. In the cells grown on glucose, glycerol, and formate, addition of formate in the whole-cell assays increased FOF1 ATPase activity by ∼60% compared with cells grown on a mixture of only glucose and glycerol. In a focA mutant cultivated to the stationary phase on glucose, glycerol, and formate, FOF1 ATPase activity was double that compared with cells grown on only glucose and glycerol, while in a focA-focB double-null mutant FOF1 ATPase activity decreased by ∼50% in formate assays. These data suggest that the cell regulates the mechanism of formate translocation depending on whether formate is generated internally or added exogenously. Thus, FOF1-ATPase activity and the FocA/FocB channels together with formate hydrogenlyase activity combine to balance pH and ion gradients during fermentation in stationary phase cells in response to whether formate is generated metabolically or supplied in high concentration from the environment
Regioselective terminal bromination of fluorinated oligophenylenes
No full textHerein, we demonstrate an unprecedentedly selective terminal bromination of fluorinated biphenylenes and oligophenylenes in the presence of excess metallic iron. The reaction can be carried out under ambient conditions at room temperature, yielding the target compounds with up to 98% yield. The high regioselectivity and scalability make this approach superior to existing methods
MLUH-E-289_3, Buteo lagopus lagopus (Pontoppidan, 1763), eggshell
No full textInventory No.: MLUH-E-289_3, Object: eggshell, Species: Buteo lagopus lagopus (Pontoppidan, 1763), Preservation: complete preservation, Locality_loc.: Luleå Lappmarken; Quickjok, Locality today: [Kvikkjokk] Sweden, Country: SwedenDate: 02/06/1916, Collection_coll.: M. Schönwetter, published in Handbuch der Oologie, Schönwetter, Max: Vol. I, p. 167, Identification by: M. Schönwetter, Aquisition: 1936, Aquired from: A. Kricheldorf
Integrated analysis of gene expression, protein synthesis, and epigenetic modifications in alcanivorax borkumensis SK2 under iron limitation
No full textThis study aimed to understand the genetic and molecular mechanisms enabling Alcanivorax borkumensis SK2, a hydrocarbonoclastic marine bacterium, to thrive under iron-limited conditions. Using SMRT PacBio whole-genome sequencing, Illumina total RNA sequencing, and proteomics analysis, we examined the strain's response to iron-rich and iron-depleted media. Despite minimal impact on growth, significant changes in gene expression were observed when using n-tetradecane or acetate under iron limitation. Iron scarcity, depending on the carbon source, affects energy metabolism, membrane transport, lipid metabolism, stress-adaptive responses, and siderophore synthesis. We identified several methyltransferases (MTases) in the studied genome, including RS14230, which is a part of a fully functional restriction-modification (RM) system causing bipartite cytosine methylation and DNA cleavage at AgGCcT sites. Another MTase, RS09425, controls bipartite adenine methylation at GaTNNNNNGtGG motifs; however, no restriction activity at these motifs has been detected. Many epigenetically modified nucleotides lacked canonical motifs, possibly due to MTase byproducts. Notably, non-canonical modifications were statistically associated with transcriptional start sites and gene regulation, suggesting an indirect role in transcription via DNA conformation changes and its accessibility to MTases near actively transcribed genes