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Chilean higher education managers’ information systems acceptance and quality management perceptions
Get PDFChilean higher education institutions face pressure to meet quality management (QM) standards and to use educational management information systems (EMIS) for managing the information related to academic activities. This doctoral research addressed the link between the use of EMIS in higher education and the QM processes, on which insufficient research was conducted so far. Against the background of the Unified Theory of Acceptance and Use of Technology and within the QM conceptual framework, I aimed to reduce this research gap by exploring the relationship between higher education managers’ EMIS acceptance and QM perceptions, and by identifying specific manager profiles. In Study 1, a systematic review of Chilean literature suggested a close relationship between QM, accountability, and the use of EMIS. However, difficulties in implementation and long-term planning were noted. In Study 2, an instrument to assess perceptions about QM and accreditation was validated. Using this instrument, three different types of managers were identified by a cluster analysis conducted in Study 3: “Elders”, “Mediators”, and “Worker Bees.” These results are in line with previous research, as EMIS usage differs according to a person's position, individual traits, and preferences. Accordingly, a customized training program was recommended, which considered individual needs, staff plans, and the identified manager profiles. As higher education institutions developed plans to invest in more EMIS licenses and implement training, the aforementioned factors may help reduce investment costs. Additionally, the results of this doctoral research lay the ground for designing mass-customized manager training for managers based on their specific profiles and the organization's characteristics.Chilenische Hochschuleinrichtungen stehen unter dem Druck, Qualitätsmanagement (QM)-Standards zu erfüllen und Bildungsmanagement-Informationssysteme (EMIS) zu verwenden, um die auf akademische Aktivitäten bezogenen Informationen zu verwalten. Diese Dissertation setzt am bisher nur unzureichend erforschten Zusammenhang zwischen dem Einsatz von EMIS in der Hochschulbildung und den QM-Prozessen an. Vor dem Hintergrund der Unified Theory of Acceptance and Use of Technology und im Rahmen des QM-Konzepts wurde der Zusammenhang zwischen der EMIS-Akzeptanz von Hochschulmanagern und der QM-Wahrnehmung untersucht und spezifische Führungsprofile identifiziert. In Studie 1 deutete ein systematischer Überblick der chilenischen Literatur auf einen engen Zusammenhang zwischen QM, Akkreditierung und der Verwendung von EMIS hin. Allerdings wurden Schwierigkeiten bei der Umsetzung und langfristigen Planung der Qualitätsmaßnahmen festgestellt. Davon ausgehend wurde in Studie 2 ein Instrument zur Erfassung der Wahrnehmung von QM und Akkreditierung validiert. Mit diesem Instrument wurden in Studie 3 drei verschiedene Managertypen mittels Clusteranalyse identifiziert. Darauf aufbauend wurde abschließend das Konzept eines maßgeschneiderten Schulungsprogramms vorgeschlagen, das individuelle Bedürfnisse und Personalpläne berücksichtigt. Da Hochschuleinrichtungen planen in mehr EMIS-Lizenzen und Schulungen zu investieren, können die oben genannten Faktoren dazu beitragen, die Investitionskosten zu senken. Darüber hinaus legen die Ergebnisse dieser Arbeit den Grundstein für die Entwicklung massenindividualisierter Schulungsprogramme für Hochschulmanager auf Basis ihres spezifischen Profils und der Charakteristika der Organisation
Was weiß die Medizin über Risiken sexueller Aktivität im Alter und/oder bei kardialen bzw. kardiovaskulären Erkrankungen?
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Transcriptional specification and dendritic growth patterns of motion-sensing neurons in Drosophila during development
Get PDFThe development of functional circuits in the brain requires neuronal morphogenesis combined with specificity in synapse formation. Diverse morphologies of neurons are generated by the precise interactions between transcription factors in gene regulatory networks. These networks specify the development of neurons, creating elaborate branching patterns of dendrites and axons. During this growth process, synaptic partners are located in close proximity to each other within the neuropil for synapse formation. The Drosophila motion vision circuit is well understood in the adult animal regarding morphology and function. Therefore, this system provides the necessary background to study the development of motion selective neurons. In combination with the genetic accessibility of Drosophila neurons and recent advances in transcriptomic profiling approaches, it is the ideal model system for the study the development of neuronal circuits. In my PhD, I focused on primary visual motion-sensing neurons in Drosophila. These neurons, T4 and T5, exist in four subtypes (a, b, c, d), each responding preferentially to visual motion in one of the four cardinal directions. Their dendrites are oriented according to their functional response and innervate the same neuropil layer, in the medulla or lobula for T4 and T5, respectively. Their axon terminals are located in one of the four layers of the lobula plate separated by their functional identity. These two morphological characteristics, the dendrite orientation and the layer of axonal arborisation, are the only difference between T4 and T5 subtypes. Therefore, it is possible to investigate how genes specify neuronal morphologies through transcriptomic profiling by studying the growth patterns of T4 and T5 dendrites. For the first manuscript of my PhD, I performed single-cell RNA sequencing of T4 and T5 neurons at different stages of dendritic development. I found multiple transcriptional differences between subtypes. In particular, I discovered that the transcription factor grain separates a/d from b/c subtypes. grain is additionally required to specify the morphological characteristics of b/c subtypes, while suppressing a/d morphologies. Through overexpression experiments a/d subtypes could be transformed to b/c and b/c could be transformed to a/d subtypes using RNA interference experiments, morphologically. Furthermore, overexpression experiments combined with recordings of neuronal activity, mainly showed preferred direction responses of b/c subtypes. It is, thus, a necessary component of the gene regulatory network to specify T4 and T5 subtype morphologies. Additionally, I identified many differentially expressed cell surface proteins that potentially play a role in guiding the growth of T4 and T5 dendrites. In the second manuscript of this thesis, I used an ex vivo brain preparation to image single T4 dendrites during their growth phase. I could distinguish horizontal, a/b, and vertical, c/d, subtypes of T4 neurons only by their dendritic growth pattern. Furthermore, horizontal subtypes could be split into a and b subtypes based on their direction of growth. Their growth pattern shows a sequential order growing from their proximal to their distal compartment. In conclusion, this work discovered the specification of T4 and T5 neurons through transcription factors, which, combined with their dendritic growth pattern, can help us understand how gene expression determines morphologies necessary to form neuronal circuits
Stereologische Untersuchung der von Economo Zellen in Schicht V in Brodmann Area 24 im Gehirn von männlichen Patienten mit Schizophrenie
Get PDFNeuropathological studies about von Economo neurons (VENs) thrived by the end of the 20th century. VENs are specialized projection neurons restricted to a few areas of the cerebral cortex, such as the anterior cingulate cortex (ACC). The ACC is viewed as a core region in the neuropathology of schizophrenia and plays a role in cognition and emotion. VENs are especially vulnerable to those neuropsychiatric diseases in which social deficits are a hallmark. Social deficits are a known issue in schizophrenia, but so far, only a few studies investigated a possible pathology of VENs in schizophrenia. In the present study, rigorous designed-based stereology was used to determine the volume of Brodmann area (BA) 24 within the ACC and layer V of BA 24, as well as the total number and density of VENs in layer V of BA 24 in both brain hemispheres of 12 male patients with schizophrenia and 11 age-matched male controls. Patients with schizophrenia exhibited a significantly lower mean total number of VENs (-28.3%; p = 0.027). No significant alterations were found in the mean density of VENs (p = 0.128), the mean volume of BA 24 (p = 0.111) and the mean volume of layer V in BA 24 (p = 0.065). The ACC shows massive connections to other cortical and subcortical regions. Furthermore, there is evidence from neuroimaging studies of aberrant connectivity in schizophrenia. The results of the present study may therefore represent a neuroanatomical basis for altered connectivity, possibly leading to deficits in social cognition, in schizophrenia
Multifunctional metasurfaces for angular-robust operation and electrochemistry
Get PDFNanophotonics has firmly established itself as a pivotal force in the transformation and shaping of diverse sectors globally, with a pronounced impact on interdisciplinary scientific research. By effectively bridging disciplinary gaps and seamlessly integrating with other scientific fields, nanophotonics has spearheaded significant breakthroughs in information technology, medicine and healthcare, electronics, life sciences, energy, environmental science, and security, among others. As this interdisciplinary trend is expected to persist, the frontier of future research beckons at the interface between nanophotonics and emerging scientific domains or applications, holding the promise of groundbreaking discoveries yet to be unveiled. In this work, we explore light-matter interactions at the interface to electrochemistry and towards advanced sensing applications.
The first part of this work investigates nanophotonic metasurfaces based on bound states in the continuum (BICs), which are localized electromagnetic modes within the continuous spectrum of radiating waves. Due to their infinite lifetimes without radiation losses, BICs are driving research directions in lasing, non-linear optical processes, and sensing. However, conventional methods for converting BICs into leaky resonances, or quasi-BICs, with high-quality factors typically rely on breaking the in-plane inversion symmetry of metasurfaces. This results in resonances that are strongly dependent on the angle of incidence, making them unsuitable for many practical applications. Here, an emerging class of BIC-driven metasurfaces is numerically analyzed and experimentally demonstrated, where the coupling to the far field is controlled by the displacement of individual resonators. In particular, both all-dielectric and metallic as well as positive and inverse displacement-mediated metasurfaces sustaining angular-robust quasi-BICs are investigated in the mid-infrared spectral region. Their optical behavior with regard to changes in the angle of incidence is investigated and experimentally shows their superior performance compared to two conventional alternatives: silicon-based tilted ellipses and cylindrical nanoholes in gold. These findings are anticipated to open exciting perspectives for bio-sensing, conformal optical devices, and photonic devices using focused light.
In the second part of this work, we explore nanophotonics at the interface of electrochemistry. Electrocatalysis plays a crucial role in realizing the transition toward a zero-carbon future, driving research directions from green hydrogen generation to carbon dioxide reduction. Surface-enhanced infrared absorption spectroscopy (SEIRAS) is a suitable method for investigating electrocatalytic processes because it can monitor with chemical specificity the mechanisms of the reactions. However, it remains difficult to detect many relevant aspects of electrochemical reactions such as short-lived intermediates. Herein, an integrated nanophotonic-electrochemical SEIRAS platform is developed and experimentally realized for the in-situ investigation of molecular signal traces emerging during electrochemical experiments. A platinum nano-slot metasurface
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featuring strongly enhanced electromagnetic near fields is implemented and spectrally targets the weak vibrational mode of adsorbed carbon monoxide at ≈2033 cm−1. Compared to conventional unstructured platinum films, we show that our nanophotonic-electrochemical platform delivers a 27-fold improvement of the experimentally detected characteristic absorption signals, enabling the detection of new species with weak signals, fast conversions, or low surface concentrations.
In the final part of this work, we continue to build on our nanophotonic-electrochemical platform that pioneered a promising narrowband technology to study single vibrational modes of electrochemical interfaces during CO oxidation. However, many reactions involve several species or configurations of adsorption. These have to be monitored, ideally simultaneously, to provide a clear understanding of the underlying electrochemical processes. This requires reproducible and broadband sensing platforms. Here, we experimentally realize multi-band metasurface-driven SEIRAS for the in-situ study of electrochemical CO2 reduction on a Pt surface. By leveraging our reproducible and spectrally tunable platinum nano-slot metasurface, two CO adsorption configurations at 2030 cm-1 and 1840 cm-1 are locally enhanced as a proof of concept that can be extended to more vibrational bands. Our platform provides a 41-fold enhancement in the detection of characteristic absorption signals compared to conventional broadband electrochemically roughened platinum films. Thanks to the signal enhancement provided by our platform, we show that the CO bridge configuration on platinum does not play a significant role during CO2 reduction in an alkaline environment.
By providing a deeper understanding of catalytic reactions, the nanophotonic-electrochemical platform is anticipated to open exciting perspectives for electrochemical SEIRAS, surface-enhanced Raman spectroscopy, and other fields of chemistry such as photoelectrocatalysis
Infektiologische Komplikationen nach autologer Stammzelltransplantation
Get PDFIn der vorliegenden retrospektiven Studie „Infektiologische Komplikationen nach autologer Stammzelltransplantation“ wurden infektiologische Komplikationen, die infolge einer Hochdosischemotherapie mit autologer Stammzelltransplantation (ASCT) an zwei Zentren in München aufgetreten sind, untersucht. Ziel war es, die Art und Häufigkeit der beobachteten Komplikationen zu bestimmen und eine statistische Risikofaktoranalyse vorzunehmen.
Hierfür wurden die klinischen Verläufe aller Patienten, die zwischen 01/2009 und 02/2019 eine ASCT erhielten, vom Zeitpunkt der stationären Aufnahme bis Tag +120 untersucht.
Insgesamt wurden 577 ASCT bei 388 Patienten (68 % männlich) mit multiplem Myelom (n=275), Keimzelltumoren (n=50), B-Zell Non-Hodgkin-Lymphom (n=42), Hodgkin Lymphom (n=12) und T-Zell-Lymphom (n=9) durchgeführt. Das mediane Alter der Patienten betrug 60 Jahre (20-80 Jahre).
Fieber unbekannten Ursprungs (FUO) trat bei 191 (33,1 %) Patienten auf, klinisch/mikrobiologisch dokumentierte Infektionen bei 211 (36,6 %) Patienten.
Eine antibakterielle Prophylaxe war mit einem signifikant reduzierten Risiko für eine gramnegative Bakteriämie assoziiert und Patienten ohne antibakterielle Prophylaxe wiesen ein signifikant erhöhtes Risiko für eine bakterielle Pneumonie auf (Odds Ratio 2,92). Eine intensive Konditionierung mit dem BEAM bzw. RBEAM-Regime war mit einem höheren Risiko für Infektionen und einem verzögerten Engraftment assoziiert. Herpes simplex und Varizella Zoster Infektionen traten bei 5,1 % und 0 % der Patienten mit Aciclovir-Prophylaxe im Vergleich zu 4,3 % und 1,1 % ohne Prophylaxe auf (nicht signifikant). Pneumocystis jirovecii Pneumonien (PjP) wurden bei 2,2 % der Patienten mit und 2,6 % ohne PjP-Prophylaxe diagnostiziert (P=0,11). Insgesamt sind 8 Patienten (2,1 %; in Bezug auf alle ASCT 1,4 %) zwischen Tag +18 und +77 an folgenden Ursachen verstorben: Septischer Schock (n=6), Cytomegalievirus-Pneumonie (n=1), und BOOP (n=1).
Zusammenfassend sind bei ca. 70 % der Patienten Infektionen nach einer ASCT aufgetreten. Eine antibakterielle Prophylaxe war mit einem verminderten Risiko für gramnegative Bakteriämien und bakterielle Pneumonien verbunden. Das Risiko für eine PjP bzw. HSV/VZV Reaktivierung war unabhängig von der Gabe einer antifungalen bzw. antiviralen Prophylaxe gering.The retrospective study "Infektiologische Komplikationen nach autologer Stammzelltransplantation" investigated infectious complications resulting from high-dose chemotherapy (HCT) followed by autologous stem cell transplantation (ASCT). The aim of the study was to analyze the occurrence, type and outcome of infections after ASCT in a large cohort of patients. An evaluation of risk factors for infectious complications was also performed. The data were discussed in the light of current treatment recommendations.
All patients who underwent ASCT from 01/2009 to 02/2019 at two institutions in Munich were included in the study. Records were analyzed regarding to patients’ characteristics, therapy, anti-infective prophylaxis and occurrence of infections until day +120.
A total of 577 ASCT were performed in 388 patients (68 % males). 275 (71 %) suffered from multiple myeloma (MM), 50 (13 %) germ cell cancer (GCC), 42 (11 %) B-cell non-Hodgkin lymphoma, 12 (3 %) Hodgkin lymphoma, and 9 (2 %) T-cell lymphoma. The median age was 60 years (minimum age 20, maximum age 80). Fever of unknown origin (FUO) occurred in 191 cases (33.1 %) and clinically/microbiologically documented infections in 211 (36.6 %) cases. The risk of gramnegative bacteremia was significantly reduced with the use of antibacterial prophylaxis (P< 0.05), and in patients without prophylaxis the risk of bacteremia/bacterial pneumonia was significantly increased (OR 2.92, P= 0.0007). Patients who underwent intensive conditioning with BEAM or RBEAM had a higher risk of infection and delayed engraftment. Herpes simplex and varicella zoster infections were
diagnosed in 5.1 % and 0 % of patients with Acyclovir prophylaxis compared to 4.3 % and 1.1 % without (P= 0.76 and 0.60, respectively). Pneumocystis jirovecii pneumonia (PjP) occurred in 2.2 % with and in in 2.6 % patients without PjP-prophylaxis (P= 0.11). A total of 8 patients died of septic shock (n= 6), cytomegalovirus pneumonia (n= 1), and BOOP (n= 1) between day +18 and +77 (2.1 % of pts; 1.4 % of all ASCT).
In conclusion, around 73 % of patients experienced infections after ASCT. Antibacterial prophylaxis is associated with a reduced risk of bacteremia and bacterial pneumonia. However, in the present study the risk of HSV/VZV infections or PjP was low regardless of whether antiviral and PjP-prophylaxis was given or not
