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Implementation of the "bulk liquid membrane" (BLM) system was investigated in terms of its efficiency for selective removal of heavy metal ions from natural resources and industrial wastewater. In this paper, the removal of lead (II) ions through a liquid membrane system and factors that influence the process were examined. The research was performed using the homemade transport cell. Two organic solvents were used as liquid membranes: 1,2-dichloroethane and chloroform. Metal ion concentration in aqueous phases was monitored by flame atomic absorption spectrophotometry, after 4 hours of experiment. Macrocyclic ether (dicyclohexano-18-crown-6) was used as ligand for Pb (II) ions. The effects of nonionic surfactants (Triton X-100, Triton X-45 and Triton X-405) added in the receiving phase of BLM system were investigated. The results showed significant increase in transport rate compared to systems without surfactants. Considering the surfactant structure, transport rate of Pb (II) ions followed the order: TX-100 >TX-45>TX-405. Presence of TX-100 increased transport of Pb (II) ions up to 78% through chloroform and 58% through 1,2-dichloroethane.  

Srđan Barzut, M. Milosavljevic, S. Adamovic, M. Saracevic, N. Maček, M. Gnjatović

Modern access controls employ biometrics as a means of authentication to a great extent. For example, biometrics is used as an authentication mechanism implemented on commercial devices such as smartphones and laptops. This paper presents a fingerprint biometric cryptosystem based on the fuzzy commitment scheme and convolutional neural networks. One of its main contributions is a novel approach to automatic discretization of fingerprint texture descriptors, entirely based on a convolutional neural network, and designed to generate fixed-length templates. By converting templates into the binary domain, we developed the biometric cryptosystem that can be used in key-release systems or as a template protection mechanism in fingerprint matching biometric systems. The problem of biometric data variability is marginalized by applying the secure block-level Bose–Chaudhuri–Hocquenghem error correction codes, resistant to statistical-based attacks. The evaluation shows significant performance gains when compared to other texture-based fingerprint matching and biometric cryptosystems.

Ernad Jabandžić, T. Konjic, Dzenana Tomasevic

Efficient work of grids with the maximum potential utilization, together with supply and modern consumer satisfaction, as well as unpredictability of distributed energy sources, represents the challenge of successful load management. This paper proposes the load management framework and analyses state-of-the-art research activities from the area of load management in smart grids. It addresses three steps in load management framework: modelling and prediction, measurement and monitoring, and optimization and control. The original contribution of this meta-analysis and state-of-the-art review is a multi-factor approach to the process of load management with the identification of key influence factors from groups: system, context and user.

Ramana Piussi, F. Krupić, Carl Senorski, Eleonor Svantesson, David Sundemo, U. Johnson, E. Hamrin Senorski

Psychological impairments can follow an anterior cruciate ligament (ACL) injury and can impact the rehabilitation process. Our aim was to investigate experiences of sports physical therapists (PTs) in addressing psychological impairments in patients after ACL injury. We conducted four focus group interviews with fourteen sports PTs. The PTs’ experiences of working with psychological impairments after ACL injury were summarized in four main categories: (1) “Calling for a guiding light”, where PTs stated that the most common method of acquiring knowledge on addressing psychological impairments was through discussions with colleagues, and, at the same time, PTs expressed an insufficient knowledge of how to address psychological impairments; (2) “Meeting the burden of psychological impairments” where PTs stated that psychological impairments are greater than physical; (3) “Trying to balance physical and psychological aspects” where patient education and assessments were reported to be important in order to understand psychological impairments during rehabilitation; and (4) “Goal setting: a helpful challenge” where sports PTs expressed a need for specific knowledge of the rehabilitation of psychological impairments following ACL injury. To help provide the current best practice, we encourage researchers to develop psychologically centered interventions for rehabilitation after an ACL injury, and PTs to stay up‐to‐date with the literature published on the subject, including to implement eventual interventions.

I. Carevic, N. Štirmer, M. Serdar, N. Ukrainczyk

Since ash from wood biomass mostly ends up in landfills, recent research has focused on finding its economic and environmental added value as a potential new raw material in the construction industry. However, for wood ash to be used on an industrial scale in construction, a strategy for its proper storage must be defined. Proper storage of WBA is important to ensure quality control for applications in cementitious composites. This work investigated the aging of wood biomass ash (WBA) collected from five different power plants in Croatia and its influence on the performance of cementitious composites. WBA and cement pastes were investigated at different aging times (up to one year) using thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), isothermal calorimetry and initial and final setting times. The results showed that storage of WBA in closed and open containers resulted in carbonation and hydration of mainly free lime and periclase, respectively, which affected the reactivity and setting times of WBA cement pastes.

Paul Flynn, Veronica McCauley, A. Mujčinović, V. Radović, Š. Bojnec, Francisco Simões

Background The dependency of rural economies on agricultural practices for survival has been in decline for a number of years, seriously threatening rural communities sustainability. It is now evident that attracting young people into agricultural professions is proving difficult. As a consequence, policy measures that aim to enhance the likelihood of rural employment for young people or rural NEETs have been introduced in countries with the aim of reducing at-at-risk-poverty rates and supporting the long term viability of rural economies. The aim of this rapid review is to summarise the published literature reporting on the effectiveness of initiatives, interventions and programmes that target rural NEETs.Methods The following databases will be searched: Web of Science, SCOPUS, EBSCOhost, ERIC and ProQuest. Internet searching through Google Scholar will also be carried out. The result of the search will be downloaded and saved to Mendeley. Informed by PRISMA guidelines, duplicates will be removed. The titles and abstracts of all remaining studies will be screened by at least two independent reviewers informed by the study inclusion and exclusion criteria. Where a decision to include or exclude cannot be reached by the two independent reviewers an additional reviewer will adjudicate. All results, screening process results will be documented in tabular form and communicated in a PRISMA flow diagram.Discussion This rapid review protocol will provide a time limited state-of-the-art evidence report, specific to the challenges experienced by rural NEETs, that will help those involved in policy development, policy response initiatives and proximal implementation. It is intended that additional opportunities for innovation and/or research may be communicated to relevant stakeholders. Hence, they will be able to create a useful framework for embedding rural youth in the context of so needed structural transformation of rural communities.Systematic Review Registration This protocol has been submitted to the International Prospective Register for Systematic Reviews - PROSPERO, published, and assigned the following reference number: CRD42021236794.

K. Pavlovic, Adelina Hrkać, I. Kožul, D. Zalihić, Amra Zalihic, I. Gilja

Introduction The aim of this article was to report the long-term results of increased ileocystoplasty in 58 patients with spinal cord injury (SCI) with an impact on overall renal function and quality of life. In a representative number of patients, where we followed individual subjects for more than 20 years, we wanted to determine their quality of life and preservation of renal function after surgery. Material and methods After unsuccessful conservative therapy of urinary incontinence, increased ileocystoplasty was performed. In addition to biochemical analysis, intravenous urography (IVU) was performed preoperatively (urography and/or ultrasound assessment of the upper urinary tract) and urodynamic tests were performed in all patients preoperatively. Results After a follow-up of patients within the group (>20 years), 2 patients reported being incontinent. The median elapsed time of action was 20 (13–24) years. Vesical capacity increased in all cases postoperatively when the median vesical capacity was 420.0 (387.5–460.0) ml (p <0.001). Long-term complications included use of bladder chambers, kidney stones and urosepsis. Creatinine clearance confirmed satisfactory renal function after the elapsed time period from surgery. Conclusions The results confirmed that augmentation ileocystoplasty had excellent long-term outcomes in the definitive therapy of refractory neurogenic detrusor overactivity in patients with SCI.

For quite a while, it has been evident that homogeneous network architectures, based on cells with a uniform radiation pattern, cannot fulfill the ever increasing demand of mobile users for capacity and service quality while still preserving spectrum and energy. However, only with the introduction of the Fourth Generation mobile communication networks to deal with the surging data traffic of multimedia applications, have smaller cells been widely used to break down service zone areas of macro base stations into multiple tiers, thus improving network performance, reducing traffic congestion, and enabling better management of spectrum and energy consumption in a macro network. In this paper, we present an analytical model for assessing the efficiency of bandwidth and energy usage, as well as of network deployment, taking into account overall network investment and maintenance costs. This paves the way to the improved planning of network coverage, and its capacity and reliability, thus preserving its spectrum and energy, as well as the environment. The analysis considers the downlink of an arbitrary heterogeneous cellular network by using tools of stochastic geometry that adopt the distribution of base stations in the form of a Poisson Point Process. The proposed analytical model is verified by the according software simulations using the ns-3 network simulator. The obtained results closely match the theoretically predicted values and boundaries, clearly indicating that, in all three analyzed aspects: spectral, energy, and deploymental, the efficiency of small-cell networks was higher with respect to traditional large-cell networks and increased even further for heterogeneous (two-tier in our tests) networks.

Emir Begagić, N. Duzic, Zlatan Memic, N. Arandelovic, Anida Celebic, Hakija Bečulić

Abstract Objective To provide relevant insight into the current degree of usage of the research potential of students of biomedical sciences in Bosnia and Herzegovina. Method The chosen data collection method was online surveying via Google search engine. The target group were students of biomedical sciences in Bosnia and Herzegovina. The surveying was conducted in July 2019, and responses were subjected to descriptive statistics. Results Although the majority of participants claimed that they were familiar with the seminar and scientific papers writing methodology and that the related course is available in their faculty’s curriculum, the quality of such courses may be questioned as the majority of study participants self-reported that they do not possess or did not posses necessary knowledge for writing and publishing a scientific paper. Also, the majority of respondents reported that they have never participated in any scientific research, which questions the involvement of students in scientific research in our country as well. More than half of respondents were actively reading scientific papers, but a third of them did not have that habit. Two-thirds of students reported that they have never attended any scientific event where they could learn more about the scientific research methods. Inadequate awareness of the importance of research, lack of students’ interest in making a research, and lack of knowledge were characterized as main obstacles in conducting scientific research according to survey responses. Conclusion Information obtained through research indicate that the student potential in scientific research in Bosnia and Herzegovina has not been used in its maximal capacity, requiring several steps to be taken towards its improvement.

V. Sarajlic, Sanela Vesnic, Dalma Udovicic-Gagula, Haris Kuric, O. Akhan

PURPOSE The aim of this retrospective study was to evaluate and compare diagnostic accuracy and complication rates of percutaneous computed tomography (CT)-guided biopsies of pulmonary lesions 10-35 mm, 35-50 mm, and >50 mm, using the coaxial biopsy technique. METHODS Over a 4-year period, 235 lung biopsies were performed using the coaxial biopsy technique with 18G semi-automated true-cut needle. There were 163 (69.4%) male and 72 (30.6%) female patients, with a mean age of 64.01±9.18 years (18-85 years). The mean lesion size was 59.6±29.3 mm. The lesions were stratified into three groups according to size: lesions <35 mm (n=42, 17.9%), lesions 35-50 mm (n=53, 22.5%), and lesions >50 mm (n=140, 59.6%). Diagnostic accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for all biopsies, and for each group separately, as well as the incidence of complications. RESULTS The overall diagnostic accuracy was 95.4%, with 95.52% sensitivity, 100% specificity, 100% PPV, and 47.37% NPV. For lesions <35 mm, diagnostic accuracy, sensitivity, and PPV were 100%. The lowest diagnostic accuracy was 93.9% in lesions >50 mm, with 93.65% sensitivity, 100% specificity, 100% PPV, and 42.86% NPV. An adequate sample was obtained in 219 core biopsies (93.2%), while 16 biopsies (6.8%) were nondiagnostic due to necrosis (4.25%) and insufficient biopsy material (2.55%). The most frequent complication was minor pneumothorax, which was seen at a rate of 19.1%; pneumothorax requiring chest tube placement occurred in 3 patients (1.3%). CONCLUSION Diagnostic accuracy decreased with increasing lesion size. On the other hand, complication rates were higher in smaller lesions, more distanced from the pleura.

E. Alickovic, E. Ng, L. Fiedler, S. Santurette, H. Innes-Brown, C. Graversen

Objectives Previous research using non-invasive (magnetoencephalography, MEG) and invasive (electrocorticography, ECoG) neural recordings has demonstrated the progressive and hierarchical representation and processing of complex multi-talker auditory scenes in the auditory cortex. Early responses (<85 ms) in primary-like areas appear to represent the individual talkers with almost equal fidelity and are independent of attention in normal-hearing (NH) listeners. However, late responses (>85 ms) in higher-order non-primary areas selectively represent the attended talker with significantly higher fidelity than unattended talkers in NH and hearing–impaired (HI) listeners. Motivated by these findings, the objective of this study was to investigate the effect of a noise reduction scheme (NR) in a commercial hearing aid (HA) on the representation of complex multi-talker auditory scenes in distinct hierarchical stages of the auditory cortex by using high-density electroencephalography (EEG). Design We addressed this issue by investigating early (<85 ms) and late (>85 ms) EEG responses recorded in 34 HI subjects fitted with HAs. The HA noise reduction (NR) was either on or off while the participants listened to a complex auditory scene. Participants were instructed to attend to one of two simultaneous talkers in the foreground while multi-talker babble noise played in the background (+3 dB SNR). After each trial, a two-choice question about the content of the attended speech was presented. Results Using a stimulus reconstruction approach, our results suggest that the attention-related enhancement of neural representations of target and masker talkers located in the foreground, as well as suppression of the background noise in distinct hierarchical stages is significantly affected by the NR scheme. We found that the NR scheme contributed to the enhancement of the foreground and of the entire acoustic scene in the early responses, and that this enhancement was driven by better representation of the target speech. We found that the target talker in HI listeners was selectively represented in late responses. We found that use of the NR scheme resulted in enhanced representations of the target and masker speech in the foreground and a suppressed representation of the noise in the background in late responses. We found a significant effect of EEG time window on the strengths of the cortical representation of the target and masker. Conclusion Together, our analyses of the early and late responses obtained from HI listeners support the existing view of hierarchical processing in the auditory cortex. Our findings demonstrate the benefits of a NR scheme on the representation of complex multi-talker auditory scenes in different areas of the auditory cortex in HI listeners.

A. Kommini, Z. Akšamija

Recent research on twisted bilayer graphene (TBG) uncovered that its twist-angle-dependent electronic structure leads to a host of unique properties, such as superconductivity, correlated insulating states, and magnetism. The flat bands that emerge at low twist angles in TBG result in sharp features in the electronic density of states, affecting transport. Here we show that they lead to superior and tuneable thermoelectric (TE) performance. Combining an iterative Boltzmann transport equation solver and electronic structure from an exact continuum model, we calculate TE transport properties of TBG at different twist angles, carrier densities, and temperatures. Our simulations show the room-temperature TE power factor (PF) in TBG reaches 40 mW m−1 K−2, significantly higher than single-layer graphene and among the highest reported to date. The peak PF is observed near the magic angle, at a twist angle of ≈1.3∘, and near complete band filling. We elucidate that its dependence is driven by two opposing forces: the band gap between the flat and remote bands suppresses bipolar transport and improves the Seebeck coefficient but the gap decreases with twist angle; on the other hand, the Fermi velocity, which impacts conductivity, is smallest at the magic angle and rises with twist angle. We observed a further increase in the PF of TBG with decreasing temperature. The strong TE performance, along with the ability to fine-tune transport using twist angle, makes TBG an interesting candidate for future research and applications in energy conversion and thermal sensing and management.

D. Saunte, M. Pereiro-Ferreirós, C. Rodríguez-Cerdeira, A. Sergeev, M. Arabatzis, A. Prohic, B. M. Piraccini, P. Lecerf et al.

Dermatophytosis is a world‐wide distributed common infection. Antifungal drug resistance in dermatophytosis used to be rare, but unfortunately the current Indian epidemic of atypical widespread recalcitrant and terbinafine‐resistant dermatophytosis is spreading and has sporadically been reported in Europe.

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