973 resultados para cosmological applications of theories with extra dimensions


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In den letzten drei Jahrzehnten sind Fernerkundung und GIS in den Geowissenschaften zunehmend wichtiger geworden, um die konventionellen Methoden von Datensammlung und zur Herstellung von Landkarten zu verbessern. Die vorliegende Arbeit befasst sich mit der Anwendung von Fernerkundung und geographischen Informationssystemen (GIS) für geomorphologische Untersuchungen. Durch die Kombination beider Techniken ist es vor allem möglich geworden, geomorphologische Formen im Überblick und dennoch detailliert zu erfassen. Als Grundlagen werden in dieser Arbeit topographische und geologische Karten, Satellitenbilder und Klimadaten benutzt. Die Arbeit besteht aus 6 Kapiteln. Das erste Kapitel gibt einen allgemeinen Überblick über den Untersuchungsraum. Dieser umfasst folgende morphologische Einheiten, klimatischen Verhältnisse, insbesondere die Ariditätsindizes der Küsten- und Gebirgslandschaft sowie das Siedlungsmuster beschrieben. Kapitel 2 befasst sich mit der regionalen Geologie und Stratigraphie des Untersuchungsraumes. Es wird versucht, die Hauptformationen mit Hilfe von ETM-Satellitenbildern zu identifizieren. Angewandt werden hierzu folgende Methoden: Colour Band Composite, Image Rationing und die sog. überwachte Klassifikation. Kapitel 3 enthält eine Beschreibung der strukturell bedingten Oberflächenformen, um die Wechselwirkung zwischen Tektonik und geomorphologischen Prozessen aufzuklären. Es geht es um die vielfältigen Methoden, zum Beispiel das sog. Image Processing, um die im Gebirgskörper vorhandenen Lineamente einwandfrei zu deuten. Spezielle Filtermethoden werden angewandt, um die wichtigsten Lineamente zu kartieren. Kapitel 4 stellt den Versuch dar, mit Hilfe von aufbereiteten SRTM-Satellitenbildern eine automatisierte Erfassung des Gewässernetzes. Es wird ausführlich diskutiert, inwieweit bei diesen Arbeitsschritten die Qualität kleinmaßstäbiger SRTM-Satellitenbilder mit großmaßstäbigen topographischen Karten vergleichbar ist. Weiterhin werden hydrologische Parameter über eine qualitative und quantitative Analyse des Abflussregimes einzelner Wadis erfasst. Der Ursprung von Entwässerungssystemen wird auf der Basis geomorphologischer und geologischer Befunde interpretiert. Kapitel 5 befasst sich mit der Abschätzung der Gefahr episodischer Wadifluten. Die Wahrscheinlichkeit ihres jährlichen Auftretens bzw. des Auftretens starker Fluten im Abstand mehrerer Jahre wird in einer historischen Betrachtung bis 1921 zurückverfolgt. Die Bedeutung von Regentiefs, die sich über dem Roten Meer entwickeln, und die für eine Abflussbildung in Frage kommen, wird mit Hilfe der IDW-Methode (Inverse Distance Weighted) untersucht. Betrachtet werden außerdem weitere, regenbringende Wetterlagen mit Hilfe von Meteosat Infrarotbildern. Genauer betrachtet wird die Periode 1990-1997, in der kräftige, Wadifluten auslösende Regenfälle auftraten. Flutereignisse und Fluthöhe werden anhand von hydrographischen Daten (Pegelmessungen) ermittelt. Auch die Landnutzung und Siedlungsstruktur im Einzugsgebiet eines Wadis wird berücksichtigt. In Kapitel 6 geht es um die unterschiedlichen Küstenformen auf der Westseite des Roten Meeres zum Beispiel die Erosionsformen, Aufbauformen, untergetauchte Formen. Im abschließenden Teil geht es um die Stratigraphie und zeitliche Zuordnung von submarinen Terrassen auf Korallenriffen sowie den Vergleich mit anderen solcher Terrassen an der ägyptischen Rotmeerküste westlich und östlich der Sinai-Halbinsel.

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In the last 20-30 years, the implementation of new technologies from the research centres to the food industry process was very fast. The infrared thermography is a tool used in many fields, including agriculture and food science technology, because of it's important qualities like non-destructive method, it is fast, it is accurate, it is repeatable and economical. Almost all the industrial food processors have to use the thermal process to obtain an optimal product respecting the quality and safety standards. The control of temperature of food products during the production, transportation, storage and sales is an essential process in the food industry network. This tool can minimize the human error during the control of heat operation, and reduce the costs with personal. In this thesis the application of infrared thermography (IRT) was studies for different products that need a thermal process during the food processing. The background of thermography was presented, and also some of its applications in food industry, with the benefits and limits of applicability. The measurement of the temperature of the egg shell during the heat treatment in natural convection and with hot-air treatment was compared with the calculated temperatures obtained by a simplified finite element model made in the past. The complete process shown a good results between calculated and observed temperatures and we can say that this technique can be useful to control the heat treatments for decontamination of egg using the infrared thermography. Other important application of IRT was to determine the evolution of emissivity of potato raw during the freezing process and the control non-destructive control of this process. We can conclude that the IRT can represent a real option for the control of thermal process from the food industry, but more researches on various products are necessary.

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The dynamics of a passive back-to-back test rig have been characterised, leading to a multi-coordinate approach for the analysis of arbitrary test configurations. Universal joints have been introduced into a typical pre-loaded back-to-back system in order to produce an oscillating torsional moment in a test specimen. Two different arrangements have been investigated using a frequency-based sub-structuring approach: the receptance method. A numerical model has been developed in accordance with this theory, allowing interconnection of systems with two-coordinates and closed multi-loop schemes. The model calculates the receptance functions and modal and deflected shapes of a general system. Closed form expressions of the following individual elements have been developed: a servomotor, damped continuous shaft and a universal joint. Numerical results for specific cases have been compared with published data in literature and experimental measurements undertaken in the present work. Due to the complexity of the universal joint and its oscillating dynamic effects, a more detailed analysis of this component has been developed. Two models have been presented. The first represents the joint as two inertias connected by a massless cross-piece. The second, derived by the dynamic analysis of a spherical four-link mechanism, considers the contribution of the floating element and its gyroscopic effects. An investigation into non-linear behaviour has led to a time domain model that utilises the Runge-Kutta fourth order method for resolution of the dynamic equations. It has been demonstrated that the torsional receptances of a universal joint, derived using the simple model, result in representation of the joint as an equivalent variable inertia. In order to verify the model, a test rig has been built and experimental validation undertaken. The variable inertia of a universal joint has lead to a novel application of the component as a passive device for the balancing of inertia variations in slider-crank mechanisms.

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Rapid and sensitive detection of chemical and biological analytes becomes increasingly important in areas such as medical diagnostics, food control and environmental monitoring. Optical biosensors based on surface plasmon resonance (SPR) and optical waveguide spectroscopy have been extensively pushed forward in these fields. In this study, we combine SPR, surface plasmon-enhanced fluorescence spectroscopy (SPFS) and optical waveguide spectroscopy with hydrogel thin film for highly sensitive detection of molecular analytes.rnrnA novel biosensor based on SPFS which was advanced through the excitation of long range surface plasmons (LRSPs) is reported in this study. LRSPs are special surface plasmon waves propagating along thin metal films with orders of magnitude higher electromagnetic field intensity and lower damping than conventional SPs. Therefore, their excitation on the sensor surface provides further increased fluorescence signal. An inhibition immunoassay based on LRSP-enhanced fluorescence spectroscopy (LRSP-FS) was developed for the detection of aflatoxin M1 (AFM1) in milk. The biosensor allowed for the detection of AFM1 in milk at concentrations as low as 0.6 pg mL-1, which is about two orders of magnitude lower than the maximum AFM1 residue level in milk stipulated by the European Commission legislation.rnrnIn addition, LRSPs probe the medium adjacent to the metallic surface with more extended evanescent field than regular SPs. Therefore, three-dimensional binding matrices with up to micrometer thickness have been proposed for the immobilization of biomolecular recognition elements with large surface density that allows to exploit the whole evanescent field of LRSP. A photocrosslinkable carboxymethyl dextran (PCDM) hydrogel thin film is used as a binding matrix, and it is applied for the detection of free prostate specific antigen (f-PSA) based on the LRSP-FS and sandwich immunoassay. We show that this approach allows for the detection of f-PSA at low femto-molar range, which is approximately four orders of magnitude lower than that for direct detection of f-PSA based on the monitoring of binding-induced refractive index changes.rnrnHowever, a three dimensional hydrogel binding matrix with micrometer thickness can also serve as an optical waveguide. Based on the measurement of binding-induced refractive index changes, a hydrogel optical waveguide spectroscopy (HOWS) is reported for a label-free biosensor. This biosensor is implemented by using a SPR optical setup in which a carboxylated poly(N-isoproprylacrylamide) (PNIPAAm) hydrogel film is attached on a metallic surface and modified by protein catcher molecules. Compared to regular SPR biosensor with thiol self-assembled monolayer (SAM), HOWS provides an order of magnitude improved resolution in the refractive index measurements and enlarged binding capacity owing to its low damping and large swelling ratio, respectively. A model immunoassay experiment revealed that HOWS allowed detection of IgG molecules with a 10 pM limit of detection (LOD) that was five-fold lower than that achieved for SPR with thiol SAM. For the high capacity hydrogel matrix, the affinity binding was mass transport limited.rnrnThe mass transport of target molecules to the sensor surface can play as critical a role as the chemical reaction itself. In order to overcome the diffusion-limited mass transfer, magnetic iron oxide nanoparticles were employed. The magnetic nanoparticles (MNPs) can serve both as labels providing enhancement of the refractive index changes, and “vehicles” for rapidly delivering the analytes from sample solution to an SPR sensor surface with a gradient magnetic field. A model sandwich assay for the detection of β human chorionic gonadotropin (βhCG) has been utilized on a gold sensor surface with metallic diffraction grating structure supporting the excitation of SPs. Various detection formats including a) direct detection, b) sandwich assay, c) MNPs immunoassay without and d) with applied magnetic field were compared. The results show that the highly-sensitive MNPs immunoassay improves the LOD on the detection of βhCG by a factor of 5 orders of magnitude with respect to the direct detection.rn

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Recent advances in the fast growing area of therapeutic/diagnostic proteins and antibodies - novel and highly specific drugs - as well as the progress in the field of functional proteomics regarding the correlation between the aggregation of damaged proteins and (immuno) senescence or aging-related pathologies, underline the need for adequate analytical methods for the detection, separation, characterization and quantification of protein aggregates, regardless of the their origin or formation mechanism. Hollow fiber flow field-flow fractionation (HF5), the miniaturized version of FlowFFF and integral part of the Eclipse DUALTEC FFF separation system, was the focus of this research; this flow-based separation technique proved to be uniquely suited for the hydrodynamic size-based separation of proteins and protein aggregates in a very broad size and molecular weight (MW) range, often present at trace levels. HF5 has shown to be (a) highly selective in terms of protein diffusion coefficients, (b) versatile in terms of bio-compatible carrier solution choice, (c) able to preserve the biophysical properties/molecular conformation of the proteins/protein aggregates and (d) able to discriminate between different types of protein aggregates. Thanks to the miniaturization advantages and the online coupling with highly sensitive detection techniques (UV/Vis, intrinsic fluorescence and multi-angle light scattering), HF5 had very low detection/quantification limits for protein aggregates. Compared to size-exclusion chromatography (SEC), HF5 demonstrated superior selectivity and potential as orthogonal analytical method in the extended characterization assays, often required by therapeutic protein formulations. In addition, the developed HF5 methods have proven to be rapid, highly selective, sensitive and repeatable. HF5 was ideally suitable as first dimension of separation of aging-related protein aggregates from whole cell lysates (proteome pre-fractionation method) and, by HF5-(UV)-MALS online coupling, important biophysical information on the fractionated proteins and protein aggregates was gathered: size (rms radius and hydrodynamic radius), absolute MW and conformation.

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N-metallo ketene imines are attractive for the preparation of a wide range of organic compounds. Our research group has been engaged in the preparation and application of the N-metallo imines (SKIs). In this frame we have studied the uncatalyzed reaction of SKIs with isocyanates to give the corresponding malonamides with good yields. It has been demonstrated that the use of SKIs, instead of simple lithium anion of nitriles, is essential for the success of the reaction. A possible explanation assumes that this new reaction proceeds via a silatropism. In the course of our studies, reported in this thesis, the synthesis and the reactivity of N-silyl ketene imines in the preparation of 2,2-diaryl-3,4- dihydroxy- alcanonitrile in an uncatalyzed adol-type reaction has been performed. Our conception has been to use a chiral aldehyde to introduce asymmetric induction at the β-position and at the α-quaternary stereogenic center in the new forming diols. To achieve this goal, we used diarylacetonitrile as the substrate to form the corresponding N-trimethylsylilketene-imines to be reacted with (S)–lactic aldehyde with different protecting groups on the hydroxyl functionality. A number of 2,2-diaryl-3,4-dihydroxy-pentanenitrile were prepared with good to excellent stereo-control and satisfactory yields. Extension of this protocol to other metallo-ketene imines was performed. Accordingly, the preparation of tin ketene imines was attempted in analogy of the corresponding silyl ketene imine. The reaction of tin ketene imines with aldehydes was tested as a new tool for the synthesis of beta-hydroxynitriles starting from carbonyl compounds (aldehydes and/or ketones). Dialkyl(aryl)silyl nitriles and dialkyl(aryl)tin nitriles presents different reactivity. Finally, N-aluminium-ketene imines, as nucleophilic partner in the opening reaction of epoxides were studied. Preliminary positive results foster us to continue our studies in enlightening the scope and the limitations of this new reaction.

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Non-invasive molecular-imaging technologies are playing a key role in drug discovery, development and delivery. Positron Emission Tomography (PET) is such a molecular imaging technology and a powerful tool for the observation of various deceases in vivo. However, it is limited by the availability of vectors with high selectivity to the target and radionuclides with a physical half-life which matches the biological half-life of the observed process. The 68Ge/68Ga radionuclide generator makes the PET-nuclide anywhere available without an on-site cyclotron. Besides the perfect availability 68Ga shows well suited nuclide properties for PET, but it has to be co-ordinated by a chelator to introduce it in a radiopharmaceuticals.rnHowever, the physical half-life of 68Ga (67.7 min) might limit the spectrum of clinical applications of 68Ga-labelled radiodiagnostics. Furthermore, 68Ga-labelled analogues of endoradiotherapeuticals of longer biological half-live such as 90Y- or 177Lu-labeled peptides and proteins cannot be used to determine individual radiation dosimetry directly. rnThus, radionuclide generator systems providing positron emitting daughters of extended physical half-life are of renewed interest. In this context, generator-derived positron emitters with longer physical half-life are needed, such as 72As (T½ = 26 h) from the 72Se/72As generator, or 44Sc (T½ = 3.97 h) from the 44Ti/44Sc generator.rnIn this thesis the implementation of radioactive gallium-68 and scandium-44 for molecular imaging and nuclear medical diagnosis, beginning with chemical separation and purification of 44Ti as a radionuclide mother, investigation of pilot generators with different elution mode, building a prototype generator, development and investigation of post-processing of the generator eluate, its concentration and further purification, the labeling chemistry under different conditions, in vitro and in vivo studies of labeled compounds and, finally, in vivo imaging experiments are described.

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The present thesis is focused on the study of Organic Semiconducting Single Crystals (OSSCs) and crystalline thin films. In particular solution-grown OSSC, e.g. 4-hdroxycyanobenzene (4HCB) have been characterized in view of their applications as novel sensors of X-rays, gamma-rays, alpha particles radiations and chemical sensors. In the field of ionizing radiation detection, organic semiconductors have been proposed so far mainly as indirect detectors, i.e. as scintillators or as photodiodes. I first study the performance of 4HCB single crystals as direct X-ray detector i.e. the direct photon conversion into an electrical signal, assessing that they can operate at room temperature and in atmosphere, showing a stable and linear response with increasing dose rate. A dedicated study of the collecting electrodes geometry, crystal thickness and interaction volume allowed us to maximize the charge collection efficiency and sensitivity, thus assessing how OSSCs perform at low operating voltages and offer a great potential in the development of novel ionizing radiation sensors. To better understand the processes generating the observed X-ray signal, a comparative study is presented on OSSCs based on several small-molecules: 1,5-dinitronaphthalene (DNN), 1,8-naphthaleneimide (NTI), Rubrene and TIPS-pentacene. In addition, the proof of principle of gamma-rays and alpha particles has been assessed for 4HCB single crystals. I have also carried out an investigation of the electrical response of OSSCs exposed to vapour of volatile molecules, polar and non-polar. The last chapter deals with rubrene, the highest performing molecular crystals for electronic applications. We present an investigation on high quality, millimeter-sized, crystalline thin films (10 – 100 nm thick) realized by exploiting organic molecular beam epitaxy on water-soluble substrates. Space-Charge-Limited Current (SCLC) and photocurrent spectroscopy measurements have been carried out. A thin film transistor was fabricated onto a Cytop® dielectric layer. The FET mobility exceeding 2 cm2/Vs, definitely assess the quality of RUB films.

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This dissertation will be focused on the characterization of an atmospheric pressure plasma jet source with an application oriented diagnostic approach and the description of processes supported by this plasma source. The plasma source investigated is a single electrode plasma jet. Schlieren images, optical emission spectra, temperature and heat flux profiles are analyzed to deeply investigate the fluid dynamic, the chemical composition and the thermal output of the plasma generated with a nanosecond-pulsed high voltage generator. The maximum temperature measured is about 45 °C and values close to the room temperature are reached 10 mm down the source outlet, ensuring the possibility to use the plasma jet for the treatment of thermosensitive materials, such as, for example, biological substrate or polymers. Electrospinning of polymeric solution allows the production of nanofibrous non-woven mats and the plasma pre-treatment of the solutions leads to the realization of defect free nanofibers. The use of the plasma jet allows the electrospinnability of a non-spinnable poly(L-lactic acid) (PLLA) solution, suitable for the production of biological scaffold for the wound dressing.

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Friend murine leukemia Virus (FV) infection of immunocompetent mice is a well- established model to acquire further knowledge about viral immune suppression mechanisms, with the aim to develop therapeutics against retrovirus-induced diseases. Interestingly, BALB/c mice are infected by low doses of FV and die from FV-induced erythroleukemia, while C57/BL6 mice are infected by FV only at high viral dose, and remain persistently infected for their whole life. Due to the central role of dendritic cells (DC) in the induction of anti-viral responses, we asked for their functional role in the genotype-dependent sensitivity towards FV infection. In my PhD study I showed that bone marrow (BM)-derived DC differentiated from FV-infected BM cells obtained from FV-inoculated BALB/c (FV susceptible) and C57BL/6 (FV resistant) mice showed an increased endocytotic activity and lowered expression of MHCII and of costimulatory receptors as compared with non-infected control BMDC. FV-infected BMDC from either mouse strain were partially resistant towards stimulation-induced upregulation of MHCII and costimulators, and accordingly were poor T cell stimulators in vitro and in vivo. In addition, FV-infected BMDC displayed an altered expression profile of proinflammator cytokines and favoured Th2 polarization. Ongoing work is focussed on elucidating the functional role of proteins identified as differentially expressed in FV-infected DC in a genotype-dependent manner, which therefore may contribute to the differential course of FV infection in vivo in BALB/c versus C57BL/6 mice. So far, more than 300 proteins have been identified which are differently regulated in FV-infected vs. uninfected DC from both mouse strains. One of these proteins, S100A9, was strongly upregulated specifically in BMDC derived from FV-infected C57BL/6 BM cells. S100A9-/- mice were more sensitive towards inoculation with FV than corresponding wild type (WT) mice (both C57BL/6 background), which suggests a decisive role of this factor for anti-viral defense. In addition, FV-infected S100A9-/- BMDC showed lower motility than WT DC. The future work is aimed to further elucidate the functional importance of S100A9 for DC functions. To exploit the potential of DC for immunotherapeutic applications, in another project of this PhD study the usability of different types of functionalized nanoparticles

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Plasmonische Metallnanopartikel bündeln, verstärken und beeinflussen Licht auf nanoskopischer Ebene. Diese grundlegende Eigenschaft kommt von koheränten, kollektiven Schwingungen der Leitungsbandelektronen, die von einfallendem Licht resonant angeregt und lokalisierte Oberflächenplasmonenresonanz (LSPR) oder ‚Partikelplasmonen‘ genannt werden. Plasmonen in Metallnanopartikeln wurden bisher z.B. zur Erkennen von pathogenen Biomolekülen, bei der photothermischen Therapie und zur Verbesserung der Effizienz von Solarzellen verwendet. In dieser Arbeit werde ich meinen Fokus auf die Synthese und Funktionalisierung von Goldnanopartikeln zur Anwendung als Sensoren legen.rnrnKürzliche Verbesserungen in der nasschemischen Synthese haben zur Herstellung von Goldnanopartikel mit unterschiedlichen Formen und Größen geführt, die sich in ihren Sensoreigenschaften unterscheiden. Unter den unterschiedlichen Sensorgeometrien sind Goldnanostäbchen die bevorzugte Form zur Biomolekül-Sensorik durch LSPR. Nanostäbchen werden durch eine positiv geladene CTAB-Schicht stabilisiert, die Proteine bei neutralem pH-Wert anziehen kann. Die Adsorption und Desorption von Proteinen an der Nanopartikeloberfläche und damit die Bindungskinetiken von Proteinen kann auf Einzelmolekülebene erforscht werden. Ich zeige hier eine Studie mit hoher örtlicher und zeitlicher Auflösung um einzelne Bindungsereignisse von Fibronectin auf Goldnanostäbchen darzustellen.rnrnGoldnanostäbchen müssen mit spezifischen biologischen Erkennungselementen funktionalisiert werden um eine Analyterkennung oder Proteinwechselwirkung zu erreichen. Ich funktionalisiere Goldnanostäbchen mit kurzen DNA-Sequenzen (Aptamer-Sequenzen und NTA konjugierten Polihymidinen) und habe anhand diese unterschiedlich sensitiven Partikel eine Studie mit verschiedenen Analyten (oder Protein-Protein Wechselwirkungen) erfolgreich durchgeführt.rn rnPlasmonen von Nanopartikel-Clustern koppeln miteinander, was ihre Resonanzenergie ändert. Der kontrollierte Zusammenbau von Nanopartikeln zu Dimeren oder höher geordneten Strukturen wie ‚Core-Satellites‘ können dazu dienen ihre Sensitivität zu erhöhen. Diese Cluster bieten eine hohe Sensitivität auf Grund der Anwesenheit von plasmonischen Hotspots in der Lücke zwischen zwei Partikeln. Die Plasmonkopplung ist ein Phänomen, das abhängig vom Abstand zweier Partikel zueinander ist und bildet somit die Basis von sogenannten Plasmon-Linealen. Ich habe eine Strategie entwickelt um Dimere aus Hsp90 funktionalisierten Goldnanosphären zu bilden. Diese Technik wird nicht durch Ausbleichen oder das Blinken von Farbstoffen limitiert und ich zeige zum ersten Mal wie man dadurch dynamische Proteinkonformationen untersuchen kann.rn

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Plasmons in metal nanoparticles respond to changes in their local environment by a spectral shift in resonance. Here, the potential of plasmonic metal nanoparticles for label-free detection and observation of biological systems is presented. Comparing the material silver and gold concerning plasmonic sensitivity, silver nanoparticles exhibit a higher sensitivity but their chemical instability under light exposure limits general usage. A new approach combining results from optical dark-field microscopy and transmission electron microscopy allows localization and quantification of gold nanoparticles internalized into living cells. Nanorods exposing a negatively charged biocompatible polymer seem to be promising candidates to sense membrane fluctuations of adherent cells. Many small nanoparticles being specific sensing elements can build up a sensor for parallel analyte detection without need of labeling, which is easy to fabricate, re-usable, and has sensitivity down to nanomolar concentrations. Besides analyte detection, binding kinetics of various partner proteins interacting with one protein of interest are accessible in parallel. Gold nanoparticles are able to sense local oscillations in the surface density of proteins on a lipid bilayer, which could not be resolved so far. Studies on the fluorescently labeled system and the unlabeled system identify an influence of the label on the kinetics.

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The main objective of this study is to reveal the housing patterns in Cairo as one of the most rapidly urbanizing city in the developing world. The study outlines the evolution of the housing problem and its influencing factors in Egypt generally and in Cairo specifically. The study takes into account the political transition from the national state economy to the open door policy, the neo-liberal period and finally to the housing situation after the January 2011 Revolution. The resulting housing patterns in Cairo Governorate were identified as (1) squatter settlements, (2) semi-informal settlements, (3) deteriorated inner pockets, and (4) formal settlements. rnThe study concluded that the housing patterns in Cairo are reflecting a multifaceted problem resulting in: (1) the imbalance between the high demand for affordable housing units for low-income families and the oversupply of upper-income housing, (2) the vast expansion of informal areas both on agricultural and desert lands, (3) the deterioration of the old parts of Cairo without upgrading or appropriate replacement of the housing structure, and (4) the high vacancy rate of newly constructed apartmentsrnThe evolution and development of the current housing problem were attributed to a number of factors. These factors are demographic factors represented in the rapid growth of the population associated with urbanization under the dictates of poverty, and the progressive increase of the prices of both buildable land and building materials. The study underlined that the current pattern of population density in Cairo Governorate is a direct result of the current housing problems. Around the depopulation core of the city, a ring of relatively stable areas in terms of population density has developed. Population densification, at the expense of the depopulation core, is characterizing the peripheries of the city. The population density in relation to the built-up area was examined using Landsat-7 ETM+ image (176/039). The image was acquired on 24 August 2006 and considered as an ideal source for land cover classification in Cairo since it is compatible with the population census 2006.rnConsidering that the socio-economic setting is a driving force of change of housing demand and that it is an outcome of the accumulated housing problems, the socio-economic deprivations of the inhabitants of Cairo Governorate are analyzed. Small administrative units in Cairo are categorized into four classes based on the Socio-Economic Opportunity Index (SEOI). This index is developed by using multiple domains focusing on the economic, educational and health situation of the residential population. The results show four levels of deprivation which are consistent with the existing housing patterns. Informal areas on state owned land are included in the first category, namely, the “severely deprived” level. Ex-formal areas or deteriorated inner pockets are characterized as “deprived” urban quarters. Semi-informal areas on agricultural land concentrate in the third category of “medium deprived” settlements. Formal or planned areas are included mostly in the fourth category of the “less deprived” parts of Cairo Governorate. rnFor a better understanding of the differences and similarities among the various housing patterns, four areas based on the smallest administrative units of shiakhat were selected for a detailed study. These areas are: (1) El-Ma’desa is representing a severely deprived squatter settlement, (2) Ain el-Sira is an example for an ex-formal deprived area, (3) El-Marg el-Qibliya was selected as a typical semi-informal and medium deprived settlement, and (4) El-Nozha is representing a formal and less deprived area.rnThe analysis at shiakhat level reveals how the socio-economic characteristics and the unregulated urban growth are greatly reflected in the morphological characteristics of the housing patterns in terms of street network and types of residential buildings as well as types of housing tenure. It is also reflected in the functional characteristics in terms of land use mix and its degree of compatibility. It is concluded that the provision and accessibility to public services represents a performance measure of the dysfunctional structure dominating squatter and semi-informal settlements on one hand and ample public services and accessibility in formal areas on the other hand.rn

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3,5-dimethyl-4-nitroisoxazole derivatives are useful synthetic intermediates as the isoxazole nucleus chemically behaves as an ester, but establish better-defined interactions with chiral catalysts and lability of its N-O aromatic bond can unveil other groups such as 1,3-dicarbonyl compounds or carboxylic acids. In the present work, these features are employed in a 3,5-dimethyl-4-nitroisoxazole based synthesis of the γ-amino acid pregabalin, a medication for the treatment of epilepsy and neuropatic pain, in which this moiety is fundamental for the enantioselective formation of a chiral center by interaction with doubly-quaternized cinchona phase-transfer catalysts, whose ability of asymmetric induction will be investigated. Influence of this group in cinchona-derivatives catalysed stereoselective addition and Darzens reaction of a mono-chlorinated 3,5-dimethyl-4-nitroisoxazole and benzaldehyde will also be investigated.

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In this review an overview about biological applications of magnetic colloidal nanoparticles will be given, which comprises their synthesis, characterization, and in vitro and in vivo applications. The potential future role of magnetic nanoparticles compared to other functional nanoparticles will be discussed by highlighting the possibility of integration with other nanostructures and with existing biotechnology as well as by pointing out the specific properties of magnetic colloids. Current limitations in the fabrication process and issues related with the outcome of the particles in the body will be also pointed out in order to address the remaining challenges for an extended application of magnetic nanoparticles in medicine.