Photoinduced molecule formation of spatially separated atoms on helium nanodroplets

Besides the use as cold matrix for spectroscopic studies, superfluid helium droplets have served as a cold environment for the synthesis of molecules and clusters. Since vibrational frequencies of molecules in helium droplets exhibit almost no shift compared to the free molecule values, one could assume the solvated particles move frictionless and undergo a reaction as soon as their paths cross. There have been a few unexplained observations that seemed to indicate cases of two species on one droplet not forming bonds but remaining isolated. In this work, we performed a systematic study of helium droplets doped with one rubidium and one strontium atom showing that besides a reaction to RbSr, there is a probability of finding separated Rb and Sr atoms on one droplet that only react after electronic excitation. Our results further indicate that ground-state Sr atoms can reside at the surface as well as inside the droplet

Subjektive und objektive Performancemaße

Die Grundlage der Zusammenarbeit in einem wirtschaftlichen Umfeld bietet die Prinzipal-Agenten-Theorie. Sie beschreibt die Situation in der ein Auftraggeber (Prinzipal) und ein Auftragnehmer (Agent) in ein durch einen Vertrag gesteuertes Verhältnis treten welches von Zielkonflikten, asymmetrischer Information und unterschiedlicher Risikoaversion von Agent und Prinzipal geprägt ist. Die resultierenden Probleme innerhalb der Beziehung sollen mit Hilfe von Anreizsystemen gesteuert werden. Der Auftraggeber und der Auftragnehmer können unterschiedliche Verträge eingehen. Ein expliziter Vertrag kann so charakterisiert werden, dass die Leistung des Agenten sowie die Gegenleistung des Prinzipals eindeutig (objektiv) definiert und vertraglich festgelegt werden kann und darüberhinaus von Dritten (z.B.: einem Gericht) verifiziert werden kann. Die Rahmenbedingungen von impliziten Verträgen dagegen können nicht vertraglich festgehalten werden und nicht von Dritten verifiziert werden. Es wird gezeigt, dass Reputationseffekte und Subjektivität eine zentrale Bedeutung für die erfolgreiche Zusammenarbeit auf Basis von impliziten Verträgen aufweisen. Da es schwierig ist, alle Aspekte der Aufgabe eines Arbeitnehmers in einem expliziten Vertrag zu spezifizieren, ist es ein gebräuchlicher Weg bei der Anreizgestaltung die Verwendung von subjektiver Leistungsbewertung, zusätzlich zur objektiven Bewertung, hinzu zu ziehen. Die subjektive Leistungsbeurteilung kann hilfreich dabei sein die Leistung des Arbeitnehmers bzw. auch dessen Wirkung auf den Gesamtfirmenwert besser bewerten zu können. In der Modell Analyse wird die Kombination von subjektiven und objektiven Performancemaßen in impliziten beziehungsweise expliziten Verträgen und die Auswirkungen der kombinierten Anwendung der unterschiedlichen Performancemaßen untersucht um so die Zusammenhänge und Abhängigkeiten der verwendeten Performancemaße darzustellen

Sex hormones influence survival of patients with metastatic urothelial carcinoma undergoing immune checkpoint therapy

Introduction Clinical trials investigating efficacy of immune checkpoint inhibitors (ICI) revealed sex-specific divergent outcomes in urothelial cancer (UC), suggesting that sex hormones might play an important role in gender-specific dimorphisms of response upon ICI. However, further clinical investigations are still needed to understand the influence of sex hormones in UC. The aim of this study was to get further insights on the prognostic and predictive value of sex hormone levels in patients with metastatic UC (mUC) who underwent ICI. Material and methods Sex hormone levels of patients with mUC including luteinizing hormone (LH), follicle-stimulating hormone (FSH), LH/FSH ratio, prolactin, testosterone and 17β-estradiol (E2) were evaluated at baseline and during ICI at 6/8 weeks and 12/14 weeks. Results Twenty-eight patients (10 women, 18 men) with a median age of 70 years were included. Metastatic disease was confirmed in 21 patients (75%) after radical cystectomy while seven patients showed mUC at first diagnosis. Twelve patients (42.8%) received first line and 16 patients second line pembrolizumab. The objective response rate (ORR) was 39% (CR in 7%). The median progression-free survival (PFS) and overall survival (OS) was 5.5 and 20 months. Focusing on changes of sex hormone levels during ICI, a significant increase in FSH levels and decrease of the LH/FSH ratio was noticed in responders (p = 0.035), yet without sex-specific significance. When adjusted for sex and treatment line, a significant increase of FSH levels was confirmed in men during second line pembrolizumab. Focusing on baseline levels, LH/FSH ratio was significantly higher in female responders (p = 0.043) compared to non-responders. In women, increased LH levels and LH/FSH ratio were associated with better PFS (p = 0.014 for LH, p = 0.016 for LH/FSH ratio) and OS (p = 0.026 and p = 0.018). In male patients, increased E2 levels were linked with improved PFS (p < 0.001) and OS (p = 0.039). Conclusion Increased LH and LH/FSH values in women as well as high E2 levels in men were significant predictors of better survival. Elevated LH/FSH ratio was predictive of better response to ICI in women. These results show first clinical evidence of the potential role of sex hormones as prognostic and predictive biomarker in mUC. Further prospective analyses are needed to corroborate our findings

Probing ultrafast C-Br bond fission in the UV photochemistry of bromoform with core-to-valence transient absorption spectroscopy.

UV pump-extreme UV (XUV) probe femtosecond transient absorption spectroscopy is used to study the 268 nm induced photodissociation dynamics of bromoform (CHBr3). Core-to-valence transitions at the Br(3d) absorption edge (∼70 eV) provide an atomic scale perspective of the reaction, sensitive to changes in the local valence electronic structure, with ultrafast time resolution. The XUV spectra track how the singly occupied molecular orbitals of transient electronic states develop throughout the C-Br bond fission, eventually forming radical Br and CHBr2 products. Complementary ab initio calculations of XUV spectral fingerprints are performed for transient atomic arrangements obtained from sampling excited-state molecular dynamics simulations. C-Br fission along an approximately CS symmetrical reaction pathway leads to a continuous change of electronic orbital characters and atomic arrangements. Two timescales dominate changes in the transient absorption spectra, reflecting the different characteristic motions of the light C and H atoms and the heavy Br atoms. Within the first 40 fs, distortion from C3v symmetry to form a quasiplanar CHBr2 by the displacement of the (light) CH moiety causes significant changes to the valence electronic structure. Displacement of the (heavy) Br atoms is delayed and requires up to ∼300 fs to form separate Br + CHBr2 products. We demonstrate that transitions between the valence-excited (initial) and valence + core-excited (final) state electronic configurations produced by XUV absorption are sensitive to the localization of valence orbitals during bond fission. The change in valence electron-core hole interaction provides a physical explanation for spectral shifts during the process of bond cleavage

Genomic imprinting in mouse blastocysts is predominantly associated with H3K27me3.

In mammalian genomes, differentially methylated regions (DMRs) and histone marks including trimethylation of histone 3 lysine 27 (H3K27me3) at imprinted genes are asymmetrically inherited to control parentally-biased gene expression. However, neither parent-of-origin-specific transcription nor imprints have been comprehensively mapped at the blastocyst stage of preimplantation development. Here, we address this by integrating transcriptomic and epigenomic approaches in mouse preimplantation embryos. We find that seventy-one genes exhibit previously unreported parent-of-origin-specific expression in blastocysts (nBiX: novel blastocyst-imprinted expressed). Uniparental expression of nBiX genes disappears soon after implantation. Micro-whole-genome bisulfite sequencing (µWGBS) of individual uniparental blastocysts detects 859 DMRs. We further find that 16% of nBiX genes are associated with a DMR, whereas most are associated with parentally-biased H3K27me3, suggesting a role for Polycomb-mediated imprinting in blastocysts. nBiX genes are clustered: five clusters contained at least one published imprinted gene, and five clusters exclusively contained nBiX genes. These data suggest that early development undergoes a complex program of stage-specific imprinting involving different tiers of regulation

Cardiac Glucose and Fatty Acid Transport After Experimental Mono- and Polytrauma

OBJECTIVE The aim of this study was to define the influence of trauma on cardiac glucose and fatty acid transport. The effects were investigated in vivo in a porcine mono- and polytrauma model and in vitro in human cardiomyocytes, which were treated simultaneously with different inflammatory substances, mimicking post-traumatic inflammatory conditions. METHODS AND RESULTS In the porcine fracture- and polytrauma model, blood glucose concentrations were measured by blood gas analysis during an observation period of 72 h. The expression of cardiac glucose and fatty acid transporters in the left ventricle was determined by RT-qPCR and immunofluorescence. Cardiac and hepatic glycogen storage was examined. Furthermore, human cardiomyocytes were exposed to a defined trauma-cocktail and the expression levels of glucose- and fatty acid transporters were determined. Early after polytrauma, hyperglycaemia was observed. After 48 h and 72 h, pigs with fracture- and polytrauma developed hypoglycaemia. The propofol demand significantly increased post trauma. The hepatic glycogen concentration was reduced 72 h after trauma. Cardiac glucose and fatty acid transporters changed in both trauma models in vivo as well as in vitro in human cardiomyocytes in presence of proinflammatory mediators. CONCLUSIONS Monotrauma as well as polytrauma changed the cardiac energy transport by altering the expression of glucose and fatty acid transporters. In vitro data suggest that human cardiomyocytes shift to a state alike myocardial hibernation preferring glucose as primary energy source in order to maintain cardiac function

Engineering the impact of phonon dephasing on the coherence of a WSe2_{2} single-photon source via cavity quantum electrodynamics

Emitter dephasing is one of the key issues in the performance of solid-state single photon sources. Among the various sources of dephasing, acoustic phonons play a central role in adding decoherence to the single photon emission. Here, we demonstrate, that it is possible to tune and engineer the coherence of photons emitted from a single WSe$_2$ monolayer quantum dot via selectively coupling it to a spectral cavity resonance. We utilize an open cavity to demonstrate spectral enhancement, leveling and suppression of the highly asymmetric phonon sideband, finding excellent agreement with our microscopic theory. Most importantly, the impact of cavity tuning on the dephasing is directly assessed via optical interferometry, which clearly points out the capability to utilize light-matter coupling to steer and design dephasing and coherence of the emission properties of atomically thin crystals

Factores relacionados con el acceso a los servicios de salud de la población de la comunidad de Armenta, departamento de Cortés, Honduras, Noviembre 2014.

Estudio descriptivo de corte transversal. Se recomienda organizar la comunidad a través del Departamento de Vinculación Universidad Sociedad de la UNAH VS, con el fin de que la población esté representada y donde se promueva una mayor participación social para generar mayores servicios de salud, agua potable, alcantarillado. Además de gestionar ante el Ministerio de Salud la ampliación del horario de atención médica de la unidad de salud de lunes a sábado, en un horario de 8 horas laborales. Además hacer énfasis en la medicina preventiva mediante charlas educativas de educación sexual y campañas de fumigación por medio de la Municipalidad de San Pedro Sula y el Patronato de Armenta dirigido a toda la comunidad, para la prevención de las enfermedades más comunes de la aldea y creando conciencia en la personas para mejorar su cultura sanitaria

Protein Pattern Formation

Protein pattern formation is essential for the spatial organization of many intracellular processes like cell division, flagellum positioning, and chemotaxis. A prominent example of intracellular patterns are the oscillatory pole-to-pole oscillations of Min proteins in \textit{E. coli} whose biological function is to ensure precise cell division. Cell polarization, a prerequisite for processes such as stem cell differentiation and cell polarity in yeast, is also mediated by a diffusion-reaction process. More generally, these functional modules of cells serve as model systems for self-organization, one of the core principles of life. Under which conditions spatio-temporal patterns emerge, and how these patterns are regulated by biochemical and geometrical factors are major aspects of current research. Here we review recent theoretical and experimental advances in the field of intracellular pattern formation, focusing on general design principles and fundamental physical mechanisms.Comment: 17 pages, 14 figures, review articl