Robust Control of Repeated Drug Administration with Variable Doses Based on Uncertain Mathematical Model

The aim of this paper was to design a repeated drug administration strategy to reach and maintain the requested drug concentration in the body. Conservative designs require an exact knowledge of pharmacokinetic parameters, which is considered an unrealistic demand. The problem is usually resolved using the trial-and-error open-loop approach; yet, this can be considered insufficient due to the parametric uncertainties as the dosing strategy may induce an undesired behavior of the drug concentrations. Therefore, the presented approach is rather based on the paradigms of system and control theory. An algorithm was designed that computes the required doses to be administered based on the blood samples. Since repeated drug dosing is essentially a discrete time process, the entire design considers the discrete time domain. We have also presented the idea of applying this methodology for the stabilization of an unstable model, for instance, a model of tumor growth. The simulation experiments demonstrated that all variants of the proposed control algorithm can reach and maintain the desired drug concentration robustly, i.e., despite the presence of parametric uncertainties, in a way that is superior to that of the traditional open-loop approach. It was shown that the closed-loop control with the integral controller and stabilizing state feedback is robust against large parametric uncertainties

Effect of Molecular Composition of Head Group and Temperature on Micellar Properties of Ionic Surfactants with C12 Alkyl Chain

The paper analyses influences of the temperature and hydrophilic groups on micellar properties of ionic surfactants with 12-carbonic hydrophobic chains. The aim is to assess the impact of hydrophilic groups and temperature on thermodynamic parameters and micellization. This knowledge is indispensable for the formulation of new dosage forms. The method uses conductometric measurements. The following hydrophilic groups are analyzed: trimethylammonium bromide, trimethylammonium chloride, ethyldimethylammonium bromide, didodecyldimethylammonium bromide, pyridinium chloride, benzyldimethyl-ammonium chloride, methylephedrinium bromide, cis and trans-[(2-benzyloxy)-cyclohexyl-methyl]-N, N-dimethylammonium bromide, sodium sulphate and lithium sulphate. Except for a few cases, there is a good agreement between values of critical micellar concentrations (CMC) and critical vesicle concentration (CVC) obtained here and those which were obtained by other authors and/or by other physicochemical methods. Values of the CMC are compared with respect to the molar masses of hydrophilic groups. It was found that CMC values increased non-linearly with increasing system temperature. The degrees of counterion binding and thermodynamic parameters, like the standard molar Gibbs energy, enthalpy and entropy of micellization are determined and discussed in detail. The results obtained will be incorporated into in silico processes of modeling and design of optimal dosage forms, a current interdisciplinary research focus of the team

Catecholamine and insulin control of lipolysis in subcutaneous adipose tissue during long-term diet-induced weight loss in obese women.

International audienceThe aim of this study was to investigate the evolution of the adrenergic and insulin-mediated regulation of lipolysis during different phases of a 6-mo dietary intervention. Eight obese women underwent a 6-mo dietary intervention consisting of a 1-mo very low-calorie diet (VLCD) followed by a 2-mo low-calorie diet (LCD) and 3-mo weight maintenance (WM) diet. At each phase of the dietary intervention, microdialysis of subcutaneous adipose tissue (SCAT) was performed at rest and during a 3-h hyperinsulinemic euglycemic clamp. Responses of dialysate glycerol concentration (DGC) were determined at baseline and during local perfusions with adrenaline or adrenaline and phentolamine before and during the last 30 min of the clamp. Dietary intervention induced a body weight reduction and an improved insulin sensitivity. DGC progressively decreased during the clamp, and this decrease was similar during the different phases of the diet. The adrenaline-induced increase in DGC was higher at VLCD and LCD compared with baseline condition and returned to prediet levels at WM. In the probe with adrenaline and phentolamine, the increase in DGC was higher than that in the adrenaline probe at baseline and WM, but it was not different at VLCD and LCD. The results suggest that the responsiveness of SCAT to adrenaline-stimulated lipolysis increases during the calorie-restricted phases due to a reduction of the α(2)-adrenoceptor-mediated antilipolytic action of adrenaline. At WM, adrenaline-stimulated lipolysis returned to the prediet levels. Furthermore, no direct relationship between insulin sensitivity and the diet-induced changes in the regulation of lipolysis was found

D+ Atlas: Atlas of Hidden Urban Values along the Danube [46th Salon of Architecture]

D+ Атлас: Атлас скривених урбаних вредности дуж Дунава један је од главних доприноса DANUrB+ пројекта INTERREG подунавског ЕУ програма сарадње. Тим са Архитектонског факултета у Београду учествовао је као пројектни партнер у већини активности пројекта DANUrB+, чији је заслужан за концепцију и уређење овог атласа подунавских градова. Атлас се израђује у два формата – штампаном и дигиталном. У раду на изради атласа, поред тима из Београда као руководиоца, учествовала је већина партнера на пројекту, посебно тимови са других архитектонских факултета из дунавског региона: Будимпеште, Букурешта, Темишвара, Братиславе, Осијек и Софија. D+ Атлас је урбани атлас са циљем да из нове перспективе открије скривене вредности малих и средњих дунавских градова. Пре свега, формат атласа је иновативан у оквирима „Дунава“, где многи његови делови и насеља још увек нису добро мапирани и сагледани ван националног нивоа. Друго, програм атласа је да кроз мапе, али и кратке текстове, слике, шеме, табеле и дијаграме о посебностима подунавских градова и њиховом јединственом урбаном карактеру обухвати и промовише богате, иако обично скривене урбане вредности подунавских градова. наслеђе. На овај начин се заједничка градска баштина, традиција и достигнућа Дунавског региона препознају и промовишу као опште добро. Овакав приступ у концепцији атласа и презентацији његовог садржаја значи да Д+ Атлас циља на широк спектар могућих „читалаца“ широм Дунавског региона и шире. Званична промоција атласа била је на завршној конференцији DANUrB+ пројекта у Будимпешти децембра 2022. године, у присуству представника Европске уније. Други важан резултат пројекта је дигитална верзија атласа, коју можете истражити преко званичне веб странице DANUrB заједнице > www.danurb.eu.D+ Atlas: Atlas of Hidden Urban Values along the Danube is one of the main contributions of the DANUrB+ project, part of the EU's INTERREG Danube Transnational Programme. The team from the Faculty of Architecture in Belgrade participated as a project partner in most of the DANUrB+ project activities and was responsible for the conception and organization of this atlas of Danube cities. The atlas was created in two formats – printed and digital. In addition to the team from Belgrade as the lead, most of the project partners participated in the preparation of the atlas, particularly the teams from other Faculties of Architecture along the Danube: Budapest, Bucharest, Timișoara, Bratislava, Osijek, and Sofia. The D+ Atlas is an urban atlas aimed at discovering the hidden values of small and medium-sized Danube cities from a new perspective. Firstly, the atlas format is innovative within the "Danube" framework, where many of its parts and settlements are still not well-mapped and viewed beyond the national level. Secondly, the atlas program is designed to encompass and promote the rich, though usually hidden, urban values of Danube cities through maps, but also short texts, images, schemes, tables, and diagrams about the specificities of Danube cities and their unique urban heritage. In this way, the common urban heritage, traditions, and achievements of the Danube region are recognized and promoted as a common good. This approach in the conception of the atlas and the presentation of its content means that the D+ Atlas aims at a wide range of potential "readers" across the Danube region and beyond. The official promotion of the atlas took place at the final conference of the DANUrB+ project in Budapest in December 2022, in the presence of European Union representatives. Another important outcome of the project is the digital version of the atlas, which can be explored through the official DANUrB community website > www.danurb.eu.Излагање D+ Атласа на 46. Салону архитектуре у категорији ПУБЛИКАЦИЈЕ. Exhibition of the D+ Atlas at the 46th Salon of Architecture in the PUBLICATIONS category. https://raf.arh.bg.ac.rs/handle/123456789/125