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Wei Wang, R. Postoyan, D. Nešić, W. Heemels

Periodic event-triggered control (PETC) is an appealing paradigm for the implementation of controllers on platforms with limited communication resources, a typical example being networked control systems. In PETC, transmissions over the communication channel are triggered by an event generator, which depends solely on the available plant and controller data and is only evaluated at given sampling instants to enable its digital implementation. In this paper, we consider the general scenario, where the controller communicates with the plant via multiple decoupled networks. Each network may contain multiple nodes, in which case a dedicated protocol is used to schedule transmissions among these nodes. The transmission instants over the networks are asynchronous and generated by local event generators. At given sampling instants, the local event generator evaluates a rule, which only involves the measurements and the control inputs available locally, to decide whether a transmission is needed over the considered network. Following the emulation approach, we show how to design local triggering generators to ensure input-to-state stability and $\mathcal {L}_p$ stability for the overall system based on a continuous-time output-feedback controller that robustly stabilizes the network-free system. The method is applied to a class of Lipschitz nonlinear systems, for which we formulate the design conditions as linear matrix inequalities. The effectiveness of the scheme is illustrated via simulations of a nonlinear example.

Kaixiang Wang, Michael G. Ruppert, C. Manzie, D. Nešić, Y. Yong

Constant-force contact-mode atomic force microscopy (AFM) relies on a feedback control system to regulate the tip–sample interaction during imaging. Due to limitations in actuators and control, the bandwidth of the regulation system is typically small. Therefore, the scan rate is usually limited in order to guarantee a desirable image quality for a constant-rate scan. By adapting the scan rate online, further performance improvement is possible, and the conditions to this improvement have been explored qualitatively in a previous study for a wide class of possible scan patterns. In this article, a quantitative assessment of the previously proposed adaptive scan scheme is investigated through experiments that explore the impact of various degrees of freedom in the algorithm. Further modifications to the existing scheme are proposed and shown to improve the closed-loop performance. The flexibility of the proposed approach is further demonstrated by applying the algorithm to tapping-mode AFM.

Josip Lesko, P. Rastović, Anđela Azinović, Sanja Ðurasović, Ante Bogut, Jelena Zovko, M. Pavlović, Zdenka Zovko

Aim Colorectal carcinoma is one of the most common neoplasms, especially in Western countries and those with westernisation. On the other hand, high rate of metabolic syndrome (MetSy) has also been noticed, as well as in Western countries. It seems like these two conditions are somehow connected. In this study, we wish to explore some characteristics of colorectal carcinoma and its correlation with MetSy. Methods In this retrospective study the data were taken from medical records of 67 patients with colorectal carcinoma, and for 30 healthy controls. Input parameters of patients were compared mutually, as well as with parameters of healthy, control examinees that had negative screening colonoscopy for neoplasm. Results Average age of patients was 68 years. The most frequent localisation of neoplasm was on rectum (53.7%) and most frequent level was Dukes C (38.8%). The patients had MetSy more frequently when compared with controls (p=0.048), and also they had more MetSy components (p=0.006). The link between MetSy and localisation of neoplasm was not found, neither with its pathohystological characteristics. Conclusion Patients with MetSy should be warned about the increased risk of colorectal carcinoma, and, in this way, motivated for earlier and more frequent screening colonoscopies, as well as of a change of unhealthy lifestyle.

Nerma Caluk, Islam M. Mantawy, A. Azizinamini

Ultra-high performance concrete (UHPC) is a durable material that can be used in constructing new and unique structural elements. This research utilizes UHPC to construct prefabricated shells that act as stay-in-place forms for bridge columns and eliminate the use of traditional formwork. These innovative structural elements reduce the on-site construction time, improve the structural performance of the column, and act as a protective layer in aggressive environments. Generally, during the construction process, the prefabricated UHPC shell is placed around the column reinforcement, which is fabricated using conventional methods. To connect the UHPC shell and column reinforcement with the footing and footing dowels, a step made of UHPC is utilized. The UHPC step connection is designed to shift the plastic hinge away from the column-to-footing interface. In the next stage, normal concrete is cast inside the shell, forming a concrete-filled UHPC shell. The final stage of construction involves placing and connecting a prefabricated cap-beam using the same UHPC step connection. The column specimen was tested under constant axial load and incremental lateral load. In this test, the UHPC shell cracked on the north side at a drift ratio of 3%; however, the column had a significant capacity and behaved similarly to a conventional reinforced concrete column during higher cycles of drift ratios. The test was completed after the column had reached a drift ratio of 7.5% when the first bar ruptured. No damage occurred in the footing and UHPC step which proved that the design was successful in shifting the plastic hinge away from the column-to-footing interface.

Aim To present combined measles cases data and phylogenetic analysis of the virus circulated in 2018 in the Federation of Bosnia and Herzegovina (FB&H, the entity of Bosnia and Herzegovina), in order to analyse endemic transmission patterns of circulating strains and its implications for elimination efforts. Methods The data were derived from epidemiological case investigations and laboratory diagnoses based on serology, molecular detection and genotyping of the measles virus. Results During 2018 16 measles cases were reported in FB&H, of which five were classified as laboratory confirmed cases, one was an epidemiologically linked case and 10 were clinically compatible cases. Among them 12 (75.00%) cases were unvaccinated or had unknown vaccination status. The most affected population was up to 14 years of age (13/16; 81.25%). None of the cases was fully vaccinated. Viruses of other genetic lineages had been introduced in FB&H in the recent period. Two virus lineages of genotype B3 were identified. Phylogenetic analysis indicated the presence of a unique sequence of measles B3 virus in FB&H (Sarajevo). Conclusion Further strengthening of measles surveillance system and renewed efforts to increase vaccination levels are necessary to prevent disease and for elimination setting.

J. Mušanović, Azra Metović, Faruk Husremović, Samir Bejić, A. Hasković, Aida Babić, S. Šljuka

Aim To determine differences in quantitative traits of digital dermatoglyphics between breast cancer women and the women in the control group (healthy women). Methods This case-control study included digital dermatoglyphics of 50 patients with confirmed breast cancer diagnosis compared with 50 healthy examinees with the absence of familial history of any type of cancer. Collecting samples was performed among Bosnian-Herzegovinian population by Printake method. The comparison of the mean values between the examined groups was made by the Student's t-test and Mann-Whitney U test. Results The results showed that, with regards to the pattern intensity, no statistically significant difference was detected between the two examined groups (p>0.05).The absence of any significant difference in the number of papillary ridges on an individual finger between the breast cancer patients and the control group was found (p>0.05), although the total number of papillary ridges on all ten fingers had somewhat lower values in the examined group. Conclusion This research confirms the existence of genetic predisposition for breast cancer development, emphasizing the relevance of hereditary factors in the ethiopathogenesis of this disease. The quantitative traits of digital dermatoglyphics were not a reliable and predictive tool for detecting a potential risk for breast cancer in small populations.

Aim To determine stereological structural parameters of the parenchymal part of the placenta, placental weight and volume of adolescent pregnant women and their correlation with newborns' birth weight. Methods This prospective study was conducted on a total of 60 human placentas of term pregnancy, divided into two groups according to the age of pregnant women. Experimental group consisted of 30 placentas of pregnant women aged 13-19 years. Control group consisted of 30 placentas of pregnant women aged 20-35 years. Stereological analysis was performed. Results Volumetric density of terminal villi of adolescent placentas was significantly higher than the one of control group (p <0.0001). The volumetric density of fibrinoid of adolescent placentas was significantly lower than of the control group (p <0.0001). Total volume of terminal villi of adolescent placentas was significantly higher than of the control group (p<0.0001). The total volume of fibrinoid of adolescent placentas was significantly lower than of the control group (p<0.0001). Newborns of adolescent pregnancies had in average lower birth weight of 439.01 g compared to the newborns of the control group (p <0.00001). Conclusion Adolescent pregnancy affects placental structure, weight and volume. Newborns of adolescent pregnancy have optimal body weight.

Aim To compare the quality of the conditions for endotracheal intubation and muscle relaxation between rocuronium bromide and vecuronium bromide using the ''timing principle'' method for induction in anaesthesia. The "timing principle" includes the administration of muscle relaxants before the hypnotic agent during induction in anaesthesia. Method Sixty patients who had undergone elective surgery were randomly allocated into two equal groups using muscle relaxants: rocuronium (group R) and vecuronium (group V). The intubation conditions were assessed using Cooper's scoring system, based on jaw relaxation, vocal cords position and response to intubation. The quality of muscle relaxation was evaluated by recording the time of clinical weakness, a count of ''train of four'' (TOF) twitches at intubation, the time of loss TOF response and duration of direct laryngoscopy. Results The intubation conditions were excellent in 100% of patients in the group R versus excellent in 80% and good in 20% of patients in the group V (p<0.05). The time of clinical weakness was statistically significantly shorter in the group R than in the group V (p<0.000). The time of loss of TOF response was statistically significantly shorter in the group R (p<0.000). The absence of TOF twitches (the level of muscle relaxation of 100%) at intubation recorded in 25 (83.3%) patients in the group R versus five (16.7%) patients in the group V (p<0.000). Duration of direct laryngoscopy did not significantly differ between the groups. Conclusion Rocuronium bromide provides better intubation conditions and greater quality of muscle relaxation than vecuronium bromide using ''timing principle'' technique.

Aim To evaluate vertebral bone marrow adiposity (BMA) using magnetic resonance spectroscopy (MRS) in postmenopausal women and to determine an association of bone density with bone marrow fat content. Methods This cross-sectional study included 120 postmenopausal women referred for osteoporosis screening. All women underwent assessment of bone mineral density by dual X-ray absorptiometry (DXA), who were divided based on T scores into osteoporosis (OST; n=60) and control group (CG; n=60). MRS was used to measure fat fraction (FF), lipid/water ratio (LWR) and fat content (FC) at vertebral spine (L1-L4). Results Mean age, menopause or reproductive period duration was not significantly different between women in OST and control group. Median LWR in OST group was significantly higher compared to CG, 31.5 (22.9-38.8) vs. 28.7 (13.7-37.3) (p=0.039). Median FC was significantly higher in OST compared to the control group, 47.0 (46.3-78.8) and 46.4 (44.3-48.6), respectively (p=0.011). FC was significantly negatively associated with BMD at lumbar spine (Rho=-0.042; p<0.001) and with BMD at hip (Rho=-0.64; p<0.001). In logistic regression model, FC remained independently associated with osteoporosis after controlling for confounders (age, menopause duration, reproductive period duration and body mass index) (OR=1.3; 95% CI 1.1-1.6). Conclusion Bone marrow adiposity is an independent predictor of low bone mass in postmenopausal women suggesting its role as a therapeutic target in postmenopausal osteoporosis management.

Katarina D Kovacevic, S. Greisenegger, Nina Buchtele, Georg Gelbenegger, Agnes Langer, J. Gilbert, Shuhao Zhu, B. Jilma

Background: The effect of conventional anti-platelet agents is limited in secondary stroke prevention, and their effects are further blunted under conditions of high shear stress in the presence of increased levels of circulating VWF. VWF mediates platelet adhesion to collagen under high shear stress and is thereby critically involved in thrombus formation at sites of stenotic extracranial intracranial arteries (reviewed by Buchtele et al. 2018). We have created a novel anti-VWF aptamer (BT200) which could be useful for secondary stroke prevention, because the anti-VWF aptamer ARC1779 effectively reduced cerebral embolization after carotid endarterectomy (Markus et al. 2011). Aims: To characterize the effects of BT200 in blood of patients with large artery atherosclerosis stroke. Methods: Blood samples were obtained from 30 patients with acute stroke Inhibition of VWF activity by BT200 was quantified by REAADS ELISA and VWF ristocetin cofactor activity (VWF:RCo), platelet function under high shear rates with the PFA-100, and ristocetin-induced platelet aggregation in whole blood. Results: The majority of stroke patients had elevated VWF:RCo levels (mean: 198%; range 55-330%). Of 15 patients receiving clopidogrel with or without aspirin, only two had a prolonged collagen adenosine diphosphate closure time (CADP-CT) >123s, and only one patient had a ristocetin induced aggregation of <20U. BT200 concentration dependently inhibited VWF activity to <3% and VWF dependent platelet function (p<0.001): BT200 invariably prolonged CADP-CT to target levels of >300s, and decreased aggregation to <20U in blood samples from all patients. Conclusions: BT200 effectively inhibits VWF activity and VWF-dependent platelet function in blood from patients with acute stroke. Results from this study proved useful for planning of the ongoing phase I and planned phase II trial.

Anka Ćorić, S. Grgić, S. Kostić, K. Vukojević, Ružica Zovko, Nataša Radica, F. Markotic

INTRODUCTION The objective of this study was to assess perceptions and attitudes among dental practitioners in relation to antibiotic usage and antibiotic resistance. METHODS Self-administered questionnaire was given to dental practitioners employed in south Croatia, west Herzegovina and Sarajevo, Bosnia and Herzegovina (N=115). RESULTS 81.7% of respondents agreed the usage of antimicrobials is frequently uncritical and unnecessary. 83.5% of dental practitioners reported that have used guidelines in their practice, however, only 9 out of 115 stated valid guidelines. One third of the respondents agreed or were undecided that the usage of antimicrobials in every oral inflammatory process treatment is justified. Furthermore, 13% was undecided and 26% agreed that pregnant women and breastfeeding women should not use any antimicrobials. However, three quarters of respondents considered they had satisfactory knowledge on antimicrobials. DISCUSSION The respondents considered they had satisfactory knowledge on antimicrobials, which was in contrast with the knowledge shown, but also expressed the need for additional education. Therefore, adequate measures include the creation of the local guidelines, their implementation, and updating the practitioners' knowledge on antibiotic use and resistance through continuous educational courses.

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