Laboratory simulation of coriolis effects on atmospheric dispersion of airborne tracers over a complex terrain

Summary The experimental research described here deals with a problem of diffusion and transport on local scale (30 km) of pollutants of urban and industrial origin, emitted into the atmosphere of a complex terrain site, with noticeable orographical features. The diffusion process was visualized and analysed in detail. The results of this research allowed acquiring the capability of forecasting environmental impact on the area, due to the sources considered. On account of its spatial scale, the phenomenon was investigated in a rotating hydraulic channel, by the method of simulation on physical model at reduced scale. Typical local atmospheric conditions, taking into account diurnal evolution of stability inside a turbulent, rotating planetary boundary layer, were modeled. Seasonal variations of sources emission rates were considered. Measurements of dilution factors at several spatial points of the model and at five levels (from ground up to a height equivalent to about 1000m) allowed mapping out concentration isolines over the site in various conditions and producing evolving contour plots which visualized the diffusion processes in a very useful way for planning purposes.     

Coupled nonlinear Schrödinger systems with potentials

Coupled nonlinear Schrödinger systems describe some physical phenomena such as the propagation in birefringent optical fibers, Kerr-like photorefractive media in optics and Bose-Einstein condensates. In this paper, we study the existence of concentrating solutions of a singularly perturbed coupled nonlinear Schrödinger system, in presence of potentials. We show how the location of the concentration points depends strictly on the potentials.     

Channel coding for asynchronous fiberoptic CDMA communications

Several studies have explored the feasibility and systems performance aspects of a code division multiple access (CDMA) format for fiberoptic networks. Previously discussed CDMA architectures would either have to tolerate a high bit error rate or be forced to use long code sequences in networks with even a moderate number of simultaneous users. The use of long sequences lowers the maximum achievable bit rate or places unrealistic requirements on the system hardware. This paper examines some of the possible improvements to system performance that could be realized by combining the CDMA format with external error correcting codes (ECCs) or a PPM format. It is determined that ECCs can be highly effective in lowering the BER, and/or increasing the achievable information bit rate and number of network users. The results are sufficiently encouraging to conclude that one should seriously consider including ECCs in any practical fiberoptic CDMA network     

Über das koordinationschemische Verhalten einiger Thioamide. II

Zusammenfassung Das koordinationschemische Verhalten einiger primärer und sekundärer Thioamide gegenüber verschiedenen Metallen wurde untersucht. Präparativ konnten kationische und anionische Komplexe sowie Neutralchelate isoliert werden. Die Bindungsverhältnisse wurden in zahlreichen Fällen IR-spektroskopisch geklärt. Eine sehr empfindliche Fe(II)-Bestimmung mit 4-Methyl-pyridin-2,6-bis-(N-methylcarbothioamid) (MPBMTA) wird beschrieben.

---

The coordination-chemical behaviour of some thioamides. II

Summary The coordination-chemical behaviour of several primary and secundary thioamides has been investigated. Cationic, anionic, and neutral chelates has been prepared. The binding relations has been clarified in numerous cases by IR-spectroscopy. A very sensitive determination of Fe(II) with 4-Methylpyridine-2,6-bis-(N-methylcarbothioamide) (MPBMTA) has been described.

---

---

Herrn Univ.-Prof. Dr. Friedrich Hecht gewidmet.

---

Für die Unterstützung dieser Arbeit danken wir dem Österreichischen Fonds zur Förderung der wissenschaftlichen Forschung.     

The effect of nonlinearities on the power spectrum of cosmic-ray fluctuations observed underground

Summary Theoretical power spectra for the fluctuations of high-rigidity cosmic rays (R≳100 GV) as detected in underground muon stations are obtained. The high-rigidity limit of diffusion theory is used and nonlinear interactions between particles and interplanetary magnetic fields are considered according to nonlinear-closure approximation theory.

---

Riassunto Si presentano i risultati sullo spettro di potenza atteso per fluttuazioni di raggi cosmici primari (rigidità >100 GV) rivelati in stazioni sottoterra. Si fa uso della teoria di diffusione nel limite di alta rigidità, e si considerano le interazioni non lineari fra particelle e campi magnetici interplanetari tramite la teoria di ?nonlinear-closure approximation?.

---

Резюме Получены теоретические степенные спектры для флуктуаций косми-ческих лучей с высокой жесткостью (R≳100 GV), которые регистрируются на подземных мюонных станциях. Используется предел высокой жесткости для диф-фузионной теории. В рамках приближения ?незамкнутости? рассматриваются нелинейные взаимодействия между частицами и межпланетными магнитными полями.

     

Hydraulic modelling of heavy-gas emission from terrain

Summary Plume trajectories and patterns of ground-level concentration of dense well opening emissions in complex terrain sites were derived from model simulations in water channel facilities. A satisfactory agreement was found among model results, field observations and theoretical models concerning plume rise and effluent dilution. This confirms the reliability of this technique when applied to previsional studies of natural gas venting or industrial losses from chemical factories and its capability to show details of the phenomenology under investigation.

---

Riassunto Sono state simulate su modelli in seala in vasca idraulica le emissioni dal suolo in atmosfera di gas inerti pesanti al fine di visualizzarne il comportamento del pennacchio e le concentrazioni di ricaduta al suolo in un sito complesso con deboli venti. I risultati sono in buon accordo con le misure reali e con i dati previsti dai modelli teorici relativamente all'innalzamento dei getti e all'allargamento, sul terreno della nube ricaduta. Ciò conferma l'affidabilità e la versatilità del metodo, in particolare relativamente a valutazioni previsionali di emissioni naturali o artificiali, e la possibilità da esso offerta di visualizzare i dettagli dei fenomeni oggetto di studio.

---

Резюме Из моделЫной имитации при помощи оборудования водянйх каналов, бйли определены плюмаж-траектории и диаграммы концентрации на поверхности земли при змиссии тяжелых инертных газов из почвы. Модельные результаты хорошо согласуются с результатами полевых измерений и данными теоретических моделей, описывающих подъем струек газа и увеличение облачности Полученные результаты подтверждают надежность предложенной техники для предсказаний естественной эмиссии или индустриальных потерь на химических заводаш, а также возможность исследовать подробности рассматриваемого явления.

     

Generating all orientablen-manifolds from (n−1)-complexes

Presentiamo una costruzione standard di tutte le PL-varietà chiuse orientabili di dimensionen, a partire da una particolare classe di complessi (n?1)-dimensionali dotati di una struttura d'ordine addizionale.     

Protein fingerprints of cultured CA3-CA1 hippocampal neurons: comparative analysis of the distribution of synaptosomal and cytosolic proteins

Background  

All studies aimed at understanding complex molecular changes occurring at synapses face the problem of how a complete view of the synaptic proteome and of its changes can be efficiently met. This is highly desirable when synaptic plasticity processes are analyzed since the structure and the biochemistry of neurons and synapses get completely reshaped. Because most molecular studies of synapses are nowadays mainly or at least in part based on protein extracts from neuronal cultures, this is not a feasible option: these simplified versions of the brain tissue on one hand provide an homogeneous pure population of neurons but on the other yield only tiny amounts of proteins, many orders of magnitude smaller than conventional brain tissue. As a way to overcome this limitation and to find a simple way to screen for protein changes at cultured synapses, we have produced and characterized two dimensional electrophoresis (2DE) maps of the synaptic proteome of CA3-CA1 hippocampal neurons in culture.     

Synthesis and characterization of zinc oxide nanoparticles: application to textiles as UV-absorbers

We report the synthesis and characterization of nanosized zinc oxide particles and their application on cotton and wool fabrics for UV shielding. The nanoparticles were produced in different conditions of temperature (90 or 150 °C) and reacting medium (water or 1,2-ethanediol). A high temperature was necessary to obtain small monodispersed particles. Fourier transformed infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray powder diffractometry (XRD) were used to characterize the nanoparticles composition, their shape, size and crystallinity. The specific surface area of the dry powders was also determined. ZnO nanoparticles were then applied to cotton and wool samples to impart sunscreen activity to the treated textiles. The effectiveness of the treatment was assessed through UV–Vis spectrophotometry and the calculation of the ultraviolet protection factor (UPF). Physical tests (tensile strength and elongation) were performed on the fabrics before and after the treatment with ZnO nanoparticles.     

Structure‐Based Design of a Macrocyclic PROTAC

Constraining a molecule in its bioactive conformation via macrocyclization represents an attractive strategy to rationally design functional chemical probes. While this approach has been applied to enzyme inhibitors or receptor antagonists, to date it remains unprecedented for bifunctional molecules that bring proteins together, such as PROTAC degraders. Herein, we report the design and synthesis of a macrocyclic PROTAC by adding a cyclizing linker to the BET degrader MZ1. A co‐crystal structure of macroPROTAC‐1 bound in a ternary complex with VHL and the second bromodomain of Brd4 validated the rational design. Biophysical studies revealed enhanced discrimination between the second and the first bromodomains of BET proteins. Despite a 12‐fold loss of binary binding affinity for Brd4, macroPROTAC‐1 exhibited cellular activity comparable to MZ1. Our findings support macrocyclization as an advantageous strategy to enhance PROTAC degradation potency and selectivity between homologous targets.