Evaporite sinkholes of the Friuli Venezia Giulia region (NE Italy)

Sinkholes are common in the Friuli Venezia Giulia (FVG) Region (NE Italy), where the presence of karstifiable rocks favours their occurrence accelerated by intense rainfalls. Their existence has been reported since the end of the 1800s along the Tagliamento Valley, in correspondence with the mantled evaporites (gypsum). Furthermore, tens of evaporite sinkholes have been documented on the reliefs adjacent to the village of Sauris and along the narrow W\u2013Eoriented valleys, where regional faults have played a major role in their spatial distribution. This paper reports for the first time an inventory of the sinkholes affecting the evaporites of the FVG Region. These phenomena were mapped and categorised using a genetic classification. The main output is an A0-format map, which incorporates a 1:50,000 scale Sinkhole Inventory Map (SIM). The SIM encompasses 552 sinkholes. The cover suffosion sinkholes are the most abundant, followed by bedrock collapses. There is a clear prevalence of the circular shape (65%) over other shapes. Diameters are 1\u2013140 m, with depths ranging 0.1\u201340 m with a mean value of 4.5 m. The SIM can motivate regional planning authorities to perform further investigations aimed to understand the geomorphological evolutions of these phenomena

Biopharmaceutical Characterization of Ciprofloxacin HCl-Ferrous Sulfate Interaction

The ciprofloxacin-iron interaction, resulting in a lower bioavailability, is well documented in vivo; however, a mechanistic explanation supported by experimental data of this interaction is missing. In the present study, ciprofloxacin hydrochloride (HCl) and ferrous sulfate interaction was simulated in vitro by performing solubility and dissolution studies in the reactive media containing ferrous sulfate. Characterization of the precipitate formed indicated its probable chemical structure as Fe(SO(4)(2-))(2)(Cl(-))(2)(ciprofloxacin)(2) x (H(2)O)(n), where n is up to 12 molecules of water. The solubility of this complex in water was estimated to be approximately 2mg/mL, being about 20-fold lower than the solubility of ciprofloxacin HCl. The solubility of the complex was used as input parameter for an in silico modeling by GastroPlus (TM) and the resulting predicted plasma time curves were in good agreement with the in vivo data. These results strongly indicate that ciprofloxacin-iron interaction in vivo is caused by the formation of a low soluble complex. This interaction was also simulated by in vitro dissolution, in which a mini scale apparatus provided more biorelevant results than the standard dissolution apparatus, probably because the drug concentrations in the mini apparatus were higher and, thus, closer to the conditions encountered in vivo

Comparative assessment of in vitro and in silico methods for aerodynamic characterization of powders for inhalation

In vitro assessment of dry powders for inhalation (DPIs) aerodynamic performance is an inevitable test in DPI development. However, contemporary trends in drug development also implicate the use of in silico methods, e.g., computational fluid dynamics (CFD) coupled with discrete phase modeling (DPM). The aim of this study was to compare the designed CFD-DPM outcomes with the results of three in vitro methods for aerodynamic assessment of solid lipid microparticle DPIs. The model was able to simulate particle-to-wall sticking and estimate fractions of particles that stick or bounce off the inhaler’s wall; however, we observed notable differences between the in silico and in vitro results. The predicted emitted fractions (EFs) were comparable to the in vitro determined EFs, whereas the predicted fine particle fractions (FPFs) were generally lower than the corresponding in vitro values. In addition, CFD-DPM predicted higher mass median aerodynamic diameter (MMAD) in comparison to the in vitro values. The outcomes of different in vitro methods also diverged, implying that these methods are not interchangeable. Overall, our results support the utility of CFD-DPM in the DPI development, but highlight the need for additional improvements in these models to capture all the key processes influencing aerodynamic performance of specific DPIs

A new view on karst genesis

Karst terrains and their specific landforms, such as sinkholes and caves, have been thoroughly studied from the second half of the nineteenth century. However, karst genesis remains a puzzling issue to this day. The results of the recent studies of ocean floor and the results obtained by drilling deep oil boreholes have raised doubts about the existing explanations of the karst landforms development and encouraged the emergence of new views on this subject matter. According to the new hypothesis, the majority of karst landforms were formed at great depths beneath sea level where dissolution of carbonates increases dramatically. Underwater dissolution first caused the formation of karst depressions and the primary network of karst conduits elongated along the existing fractures. This process was followed by further expansion of the conduits and the formation of spacious caves due to the water regression and the action of turbulent flows. It is considered that the introduction of the new concept would accelerate the development of karstology and improve the principles and methods for solving numerous practical problems such as the abstraction of quality drinking water and the research of oil, gas and bauxite deposits

Physical Geographic Characteristics and Sustainable Development of the Mountain Area in Montenegro

Montenegro is located in the Balkan Penninsula, which is extremely mountainous country. More than two thirds of the total area is mountainous. There are four macro relief units in the mountain area: mountain plains, valleys (canyons and gorges), basins, and mountains. A very dynamic physical geographic basis (geology, geomorphology, climate, hydrology) enabled the diversity and rich natural potential resorts to be formed in the mountain area in Montenegro. In the past 50 years, new industries have appeared: mining, metallurgy, energy production, traffic, and tourism, and their development has led to endangered, devastated, and polluted environments in the mountain area of Montenegro