Background We analysed the long-term revision rate, clinical outcomes and metal ion concentrations in blood over time in patients who had undergone metal-on-metal Articular Surface Replacement (ASR) hip arthroplasty. Methods A total of 38 patients (43 hips) were included: 24 patients (28 hips) underwent large-head total hip arthroplasty (XL THA), and 14 patients (15 hips) underwent hip resurfacing arthroplasty (HRA). The median follow-up time was 11 (range 7-12) years. Results None of 15 HRA implants were revised. Nine of 28 XL THA implants (32%) in 8 patients were revised. The Co ion levels significantly increased in the XL THA group (p=0.009) over a median time period of 84 (25-97) months. Conclusion The levels of Co ions in blood were higher in the patients who had undergone XL THA and increased significantly over time.

Introduction: The early approaches to prevent the spread of COVID-19 included lockdown and social distancing measures, leading to university closures. These measures forced unparalleled changes to the delivery of healthcare education. Concerns included the preparedness of faculty and students to e-learning as well as the routine availability and funding of equipment and internet bundles. This needed addressing with fully trained healthcare professionals required given rising inappropriate use of antibiotics in India, growing prevalence of non-communicable diseases as well as an increasing number of patients with joint comorbidities. Consequently, there is a need to ascertain the current impact of the pandemic on healthcare student education across India. Materials and Methods: This was a pilot study among 10 purposely selected healthcare educators in both private and public universities. The questionnaire built on published studies. Results: Identified challenges included a lack of familiarity with online education, no bedside teaching, lack of equipment and affordability of internet bundles, poor internet connectivity and postponed examinations. Ways forward included training faculty on e-learning, providing students with loans and other financial support to purchase equipment and internet bundles, establishing COVID-19 prevention protocols and protective equipment, recording lectures and tutorials to make up for lost time and simulated methods to teach clinical aspects. Conclusion: Despite challenges, there was a rapid move to online learning among surveyed universities. Alongside this, courses to address lack of familiarity with e-learning approaches with hybrid teaching approaches here to stay. The next step will be to undertake a wider study and to use the combined findings to provide future guidance.

Aquaculture net pens inspection and monitoring are important to ensure net stability and fish health in the fish farms. Remotely operated vehicles (ROVs) offer a low-cost and sophisticated solution for the regular inspection of the underwater fish net pens due to their ability of visual sensing and autonomy in a challenging and dynamic aquaculture environment. In this paper, we report the integration of an ROV with a visual servoing scheme for regular inspection and tracking of the net pens. We propose a vision-based positioning scheme that consists of an object detector, a pose generator, and a closed-loop controller. The system employs a modular approach that first utilizes two easily identifiable parallel ropes attached to the net for image processing through traditional computer vision methods. Second, the reference positions of the ROV relative to the net plane are extracted on the basis of a vision triangulation method. Third, a closed-loop control law is employed to instruct the vehicle to traverse from top to bottom along the net plane to inspect its status. The proposed vision-based scheme has been implemented and tested both through simulations and field experiments. The extensive experimental results have allowed the assessment of the performance of the scheme that resulted satisfactorily and can supplement the traditional aquaculture net pens inspection and tracking systems.

Limonene (1-methyl-4-(1-methylethenyl)-cyclohexene) is one of the most widespread monocyclic terpenes, being both a natural and industrial compound. It is widely present in the environment, including in water supplies. Therefore, it may be subjected to aqueous chlorination at water treatment stations during drinking water preparation. Besides, being a component of numerous body care and cosmetic products, it may present at high levels in swimming pool waters and could also be subjected to aqueous chlorination. Laboratory experiments with aqueous chlorination of D-limonene demonstrated the prevalence of the conjugated electrophilic addition of HOCl molecule to the double bonds of the parent molecule as the primary reaction. The reaction obeys the Markovnikov rule, as the levels of the corresponding products were higher than those of the alternative ones. Fragmentation pattern in conditions of electron ionization enabled the assigning of the structures for four primary products. The major products of the chlorination are formed by the addition of two HOCl molecules to limonene. The reactions of electrophilic addition are usually accompanied by the reactions of elimination. Thus, the loss of water molecules from the products of various generations results in the reproduction of the double bond, which immediately reacts further. Thus, a cascade of addition-elimination reactions brings the most various isomeric polychlorinated species. At a ratio of limonene/active chlorine higher than 1:10, the final products of aqueous chlorination (haloforms) start forming, while brominated haloforms represent a notable portion of these products due to the presence of bromine impurities in the used NaOCl. It is worth mentioning that the bulk products of aqueous chlorination are less toxic in the bioluminescence test on V. fischeri than the parent limonene.

The fourth industrial revolution (Industry 4.0) anticipates frequent synthesis and optimization of different architectural design decisions (ADDs) – such as deployment of software components to hardware components, service composition, production planning, and topology (plant layout) synthesis. The frequent manual search for valid and optimal architectural designs is a time- and cognition-consuming task for an engineer. This asks for automating the process of deriving different ADDs. Although automating different ADDs is intensely investigated in other domains, the current research works 1) require higher engineering effort for specifying architecture optimization problems; 2) conduct (only) sequential ADDs, leading to lower solution quality (i.e., sub-optimal production); 3) neglect re-configurability and reliability of architectures, and, thereby, offer no solution for production downtime; 4) neglect event-based execution semantics while considering timing-related issues. Therefore, I propose a Satisfiability Modulo Theories (SMT)-based framework for joint synthesis and optimization of multi-dimensional ADDs using industrial automation domain models (e.g., plant topology, product recipes, stations capabilities, etc.). This research should bring following benefits for the practitioners and researchers: 1) reduction of engineering effort for conducting different ADDs; 2) improvement of different quality attributes (e.g., production performance, reconfigurability, reliability, etc.); 3) guideline/support for a practitioner in choosing ADDs workflow to improve given quality attributes.

Digital transformation is unstoppable and ongoing process that affects all segments of our everyday lives such as healthcare, banking and finance systems, public administration, or postal and logistics systems. One of the main engines of this process, among many, is the use of cryptocurrencies. Both of these concepts are usually addressed from the firm perspective, but they should be considered from the individual’s perspective as well. Cryptocurrencies recently face increased cyber security threats, thereby affecting the digital transformation and posing additional challenges to it. Therefore, this paper gives a brief overview of security threats and challenges characteristic for cryptocurrency technology today and discusses what can be expected tomorrow. We provide insight how these challenges can affect digital transformation process and propose ways to increase the level of protection for both individuals and organizations.

The fifth generation of mobile telecommunications (5G) is one of the most important novelties of our times due to its influence on the economy and society. The advent of 5G networks and services expands the security threats landscape and requires the implementation of adequate countermeasures. This paper presents a brief overview of 5G security threats and countermeasures from operators’ perspective. The aim is to contribute to the 5G cybersecurity knowledge collection and dissemination by summarizing the key findings and identifying next steps.

A UAV (Unmanned Aerial Vehicle) is an unmanned aerial vehicle or aircraft that can be monitored remotely or flown independently using a pre-programmed flight plan. Simply, a drone is a selfpropelled vehicle heavier than air. From their beginnings and first forms to modern drones as we know them today, people have discovered many areas for their application. As the power and carrying capacity of drones has grown, so does the possibility of using them for different purposes such as logistics and postal services. The main advantage of drones in urban areas is the independence from road infrastructure and fast delivery, but several challenges need to be addressed for this type of delivery to be competitive with other modes. Many projects have dealt with this topic, but none of them has widespread use to this day. In this paper, we will present the basic challenges that arise in the use of drones for shipment delivery. The paper will present activities that should be prioritized to make a competitive type of service. The paper will present also the advantages over other types of shipment delivery and the current limitation with a future possible research area.

In the last few years, we have been active participants in globalization and the rapid growth of online commerce. This trend directly impacts logistics, postal, and courier companies. Challenges are visible in the growth and development of these companies, as well as quality of task execution and the ability to adapt to market conditions. With the impact of the SARS-COV-19 virus on the market, and due to locks during the pandemic, shoppers were forced to buy products online. This effect accelerated the trend of purchases via e-commerce, which increased the number of parcels in the technological phases of pick-up and delivery. These companies are the bearers of the first and last technological phase of shipment transport. Due to the increase in the number of shipments, postal and logistics companies are under great pressure. This is because of certain restrictions introduced during the pandemic, but also because of costs, especially fixed costs in the first and last phase of transport. This paper proposes an outsourcing model for the pick-up and delivery to convert fixed costs into variable ones.

Imposed changes in social conduct and the dynamics of living in cities, during COVID-19 pandemic, triggered an increase in the demand, availability, and accessibility of open public spaces. This has put forward questions of the relationship between open public spaces and disease transmission, as well as how planning and design strategies might be used to improve resilience in the face of future pandemics. Within this academic framework, this study focuses on object detection and human movement prediction in open public spaces, using the city of Sarajevo as a case study. Video recordings of parks and squares in morning, afternoon and evening are utilized to detect humans and predict their movements. Frame differentiation method proved to be the best for object detection and their motion. Linear regression is used on a dataset collected using the space syntax observation technique gate method. The best R-2 values, 0.97 and 0.61, are achieved for weekdays, for both parks and squares. Authors associated it with the dynamics of space use and frequency of space occupancy, which can be related to physical conditions and activity content of selected locations. The results of study provide an insight into analysis and prediction of direction, as well as density of pedestrian movement, which could be used in decision making directed towards more efficient and health oriented urban planning.

Software process improvement implies a set of complex and systematic activities of software engineering. It requires theory and models established in management, technical and social sciences. The improvement is based on the assumption that the organization if it owns mature and capable processes, would be able to deliver quality software on time and in line with predicted costs. The maturity models are initially aimed for implementation in enterprise software organizations, government organizations and within the military industry. Their complexity and the size make them difficult to use in small software organizations and companies. In such organizations the interest for use and the efforts to make an efficient and effective organization is always presented, though. In this paper, the basic and derived capability maturity models are described and cases from their implementation are analyzed, along with assessment of results of such projects in business practices. The problem of the software process improvement in small organizations is described, extracting the risks and recommendations for its enhancement. These recommendations are provided in order to set up a foundation for implementation of these models in a specific managerial and organizational environment characterized by small organizations.

The Internet of Things (IoT) connects everyone in the smart world, so the energy consumption of IoT technology is a challenging and attractive research area. The development of technology in the field of IoT has changed the way of life and enriched society with its benefits, but we must not ignore the fact that IoT consumes energy, contributes to toxic pollution, and generates electrical waste. To increase the benefits and reduce the harmfulness of IoT, there are increasing tendencies to move towards green IoT (G-IoT). The G-IoT is considered the future environmentally friendly IoT. Greening ICT technology plays a key role in G-IoT and promises many benefits to society such as efficient production, and reducing the energy used to design and distribute ICT devices and equipment. This paper will present a comprehensive overview of G-IoT technologies and strategies that demonstrate work and efforts to build a green and smart world, contributing to a safe and healthy environment, smart and high quality of life based on enabling technologies, reducing pollution, and reducing energy consumption. ICT technologies that enable G-IoT include Green RFID, Green Wireless Sensor Network (GWSN), Green Cloud Computing (GCC), Green M2M (G-M2M), and Green Data Center (GDC). The paper will also present an analysis of the importance of environmental technology processes in sustainable development, exploring the principles and roles of G-IoT in the progress of society through examining its potential for improving quality of life, environment, economic growth, and green global modernization.