Advanced IT Management

Supplementary exam paper for Advanced IT Managemen

Clear sky fraction above Indonesia: an analysis for astronomical site selection

We report a study of cloud cover over Indonesia based on meteorological satellite data, spanning over the past 15 years (from 1996 to 2010) in order to be able to select a new astronomical site capable to host a multi-wavelength astronomical observatory. High spatial resolution of meteorological satellite data acquired from {\it Geostationary Meteorological Satellite 5} ({\it GMS 5}), {\it Geostationary Operational Environmental Satellite 9} ({\it GOES 9}), and {\it Multi-functional Transport Satellite-1R} ({\it MTSAT-1R}) are used to derive yearly average clear fractions over the regions of Indonesia. This parameter is determined from temperature measurement of the IR3 channel (water vapor, 6.7 $\mu$m) for high altitude clouds (cirrus) and from the IR1 channel (10.7 $\mu$m) for lower altitude clouds. Accordingly, an algorithm is developed to detect the corresponding clouds. The results of this study are then adopted to select the best possible sites in Indonesia to be analysed further by performing in situ measurements planned for the coming years. The results suggest that regions of East Nusa Tenggara, located in south-eastern part of Indonesia, are the most promising candidates for such an astronomical site. Yearly clear sky fraction of this regions may reach better than 70 per cent with an uncertainty of 10 per cent.Comment: 15 pages, 13 figures, and 4 table

Synthesis and Anchoring of Antineoplastic Ferrocene and Phthalocyanine Derivatives on Water-Soluble Polymeric Drug Carriers Derived from Lysine and Aspartic Acid

The general synthetic strategy towards water-soluble biodegradable drug carriers and the properties that they must have are discussed. The syntheses of water-soluble biodegradable copolymers of lysine and aspartic acid as potential drug-delivering devices, having amine-functionalised side chains are then described. Covalent anchoring of carboxylic acid derivatives of the antineoplastic ferrocene and photodynamically active phthalocyanine moieties to the amine-containing drug carrier copolymers under mild coupling conditions has been achieved utilising the coupling reagent O-benzotriazolyl-N,N,N′,N′-tetramethyluronium hexafluorophosphate to promote formation of the biodegradable amide bond. Even though the parent antineoplastic ferrocene and phthalocyanine derivatives are themselves insoluble in water at pH < 7, the new carrier-drug conjugates that were obtained are well water-soluble

Beeinflussung der viszeralen Sensibilität durch somatosensorische Signale.Teil II: Summation

In einer vorangegangenen Studie (Bericht Nr. 27 dieser Reihe) wurde eine Maskierung interozeptiver (intrakolonischer) Dehnungsreize durch exterozeptive (abdominelle) Druckreize gefunden. Die vorliegende Studie sollte den umgekehrten Effekt (Summation) demonstrieren. Es lagen die Daten von 20 Versuchspersonen vor. Wichtige Ergebnisse waren: Bei einer Auswertung der Untersuchung wurde ein schwacher, aber signifikanter Summationseffekt gefunden, ganz im Gegensatz zu den in Bericht Nr. 27 dargestellten Ergebnissen. Entscheidend für diesen Unterschied sind hauptsächlich nicht psychophysikalische Unterschiede zwischen den Reizen, sondern die Art der Aufgabe: Maskierung wird gefunden, wenn zwischen zwei Reizen explizit unterschieden werden muss (wo war der Reiz?). Summation tritt hingegen auf, wenn nur noch ein aus beiden Signalen bestehender Reizkomplex erkannt werden muss (gab es einen Reiz?), ohne Unterscheidung zwischen den Komponenten

Beeinflussung der viszeralen Sensibilität durch somatosensorische Signale.Teil I: Maskierung

Ziel der Studie war die Untersuchung der Wechselwirkung interozeptiver (intrakolonischer) Dehnungsreize und exterozeptiver (abdomineller) Druckreize. Die Darbietung der interozeptiven Reize erfolgte durch Luftfüllung eines Ballons, der am Ende einer speziellen Darmsonde angebracht war und sich während der Untersuchung im Rektosigmoid befand. Zur Vermeidung von Biaseffekten wurde ein Forced-Choice-Design eingesetzt. Die Schwellen der Unterscheidbarkeit interozeptiver und exterozeptiver Reize wurden mit den Einzelschwellen verglichen. Alle Schwellen wurden mit Hilfe eines Multiple-Staircase-Algorithmus gleichzeitig bestimmt. Da ein Einfluss des Orts des externen Stimulus auf die Interaktion vermutet wurde, wurde die Messung für zwei Reizorte durchgeführt: einmal im unteren rechten Quadranten der Bauchdecke (dem internen Reizgeber zugeordnetes Dermatom), einmal im oberen linken Quadranten. Es lagen Daten von 16 Versuchspersonen vor. Es zeigte sich: Bei Reizung im entfernten Dermatom wurde eine signifikante Maskierung des internen durch den externen Reiz gefunden. Im zugeordneten Dermatom war der Effekt schwächer und nicht mehr signifikant, zeigte aber in die gleiche Richtung. Es ist daher zu vermuten, dass unter dieser Bedingung ein zusätzlicher Summationseffekt den Maskierungseffekt abschwächte. Zur Prüfung der Hypothese wurde eine weitere Untersuchung angesetzt, die in Bericht Nr. 28 dieser Reihe dargestellt ist

Impingement heat transfer with pressure recovery

A conventional impinging jet is effective at transferring a large heat flux. However a significant pressure loss is also experienced by the free jet of a jet impingement heat transfer device due to rapid expansion because it does not incorporate effective pressure recovery. A novel high-flux impingement heat transfer device, called the Tadpole, is developed to improve the heat transfer and pressure loss (performance) characteristics of the conventional impingement domain by incorporating pressure recovery with a diffuser. The Tadpole is scrutinized through an experimental comparison with a conventional jet impinging on the inner wall of a hemisphere under the turbulent flow regime. The Tadpole demonstrates promising capability by exceeding the performance characteristics of the impinging jet by up to 7.3% for the heat transfer coefficient while reducing the pressure loss by 13%. Multiple dimensional degrees of freedom in the Tadpole’s flow domain can be manipulated for an enhanced heat transfer coefficient, a reduced total pressure loss or a favourable combination of both metrics. A Computational Fluid Dynamics (CFD) model is developed, the Four-Equation Transition SST turbulence model demonstrates satisfactory experimental validation with a deviation of < 5% for the heat transfer coefficient and < 23% for the total pressure loss. The Tadpole is a promising heat transfer device for high-flux applications and is recommended for further work incorporating design improvements and multidimensional optimization.The Solar Thermal Energy Research Group (STERG) at Stellenbosch University.https://link.springer.com/journal/231hj2023Mechanical and Aeronautical Engineerin

Consequences of electron-density manipulations on the X-ray photoelectron spectroscopic properties of ferrocenyl-β-diketonato complexes of manganese(III). structure of [Mn(FcCOCHCOCH3)3]

Reaction of [Mn3(OAc)6O·3H2O](+) (1) with ferrocenyl β-diketones of the type FcCOCH2COR with R = CF3 (2a) and CH3 (2b), Ph = C6H5 (2c), and Fc = Fe(II)(η(5)-C5H4)(η(5)-C5H5) (2d) yielded a series of ferrocene-functionalized β-diketonato manganese(III) complexes 3a-3d, respectively, of general formula [Mn(FcCOCHCOR)3]. The mixed-ligand β-diketonato complex [Mn(FcCOCHCOFc)2(FcCOCHCOCH3)] (4) was obtained by reacting mixtures of diketones 2b and 2d with 1. A single-crystal X-ray structure determination of 3b (Z = 2, triclinic, space group P1̅) highlighted a weak axial elongating Jahn-Teller effect and a high degree of bond conjugation. An X-ray photoelectron spectroscopic study, by virtue of linear relationships between group electronegativities of ligand R groups, χR, or ∑χR, and binding energies of both the Fe 2p3/2 and Mn 2p3/2 photoelectron lines, confirmed communication between molecular fragments of 2a-2d as well as 3a-3d. This unprecedented observation allows prediction of binding energies from known β-diketonato side group χR values.J.C.S. acknowledges the NRF (Grant 2054243) and the UFS for financial support. Financial support from Syngaschem BV, The Netherlands, and the UFS is also gratefully acknowledged (B.E.B., E.E., and J.C.S.).http://pubs.rsc.org/en/journals/journalissues/ic2017-03-31hb2016Chemistr

Patient-reported health outcomes in long-term lung transplantation survivors

During the last three decades lung transplantation (LTx) has become a proven modality for increasing both survival and health-related quality of life (HRQoL) in patients with various end-stage lung diseases. Most previous studies have reported improved HRQoL shortly after LTx. With regard to long-term effects on HRQoL, however, the evidence is less solid. This prospective cohort study was started with 828 patients who were on the waiting list for LTx. Then, in a longitudinal follow-up, 370 post-LTx patients were evaluated annually for up to 15 years. For all wait-listed and follow-up patients, the following four HRQoL instruments were administered: State-Trait Anxiety Inventory, Zung Self-rating Depression Scale, Nottingham Health Profile, and a visual analogue scale. Cross-sectional and generalized estimating equation (GEE) analysis for repeated measures were performed to assess changes in HRQoL during follow-up. After LTx, patients showed improvement in all HRQoL domains except pain, which remained steady throughout the long-term follow-up. The level of anxiety and depressive symptoms decreased significantly and remained constant. In conclusion, this study showed that HRQoL improves after LTx and tends to remain relatively constant for the entire life span