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Objective: The aim of the present study was to evaluate the long-term clinical survival and success of chairside-fabricated single-tooth monolithic zirconia restorations on posterior teeth using the speed sintering process. Materials and Methods: Between 2012 and 2022, 250 single-tooth crowns were fabricated for 193 patients using the CEREC® chairside workflow. Restorations were fabricated from monolithic 3Y-TZP zirconia (InCoris TZI, Dentsply Sirona©, Bensheim, Germany) as full-contour crowns. The same clinician performed all procedures. Luting was performed using self-adhesive resin-based cements or glass ionomer cement. Retrospective analysis was conducted, defining survival as crowns still in function regardless of any interventions, and success as crowns that remained functional without the need for intervention. Statistical analysis was performed using Kaplan–Meier analysis, considering “refabrication” and “intervention” as endpoints. Results: Of the 250 crowns, a total of 162 (64.8%) crowns showed success. Over the whole observation period, 44 crowns (17.6%) required refabrication, and 88 (35.2%) required intervention. Mean survival without refabrication was 7.43 years, with a 5- and 7.5-year survival of 86.9% and 76.6%. The mean survival without intervention was 6.5 years, with a 5- and 7.5-year survival of 70.8% and 59.9%. Conclusions: Under appropriate technical conditions, chairside-fabricated 3Y-TZP zirconia single-tooth crowns represent a viable fabrication method. Neither the cementation mode nor the crown position—whether on premolars or molars—significantly impacted the survival rates.

Background: Virtual simulators are increasingly being introduced in dental education. This study investigates whether virtual simulators offer comparable or superior educational efficacy when compared to traditional phantom simulators. Materials and Methods: Participants were randomly allocated into groups: Virtual Preparation (SIM; n = 30) and Traditional Preparation (FRA; n = 30). Students were tasked with preparing tooth 36 for a full-cast crown during free practice for four days. Faculty staff provided feedback to both groups. Examinations were administered and graded by three examiners (preclinical and clinical consultants and a dental surgery consultant). Additionally, a survey was conducted to assess each training concept. Results: The FRA group achieved significantly better grades in the preparation exam evaluations by all three examiners, compared to the SIM group. Interrater reliability showed only moderate agreement, with the clinical examiner giving better grades than the other two. The questionnaire results indicate that while participants managed with the virtual system, they preferred the analog system for exams and patient preparation. Conclusion: Virtual simulators do not seem to be as good when it comes to practicing for a preparation exam or clinical preparation, especially for unexperienced students. However, they still appear to be useful as an additional tool for introducing students to the topic of preparation.

Chronic wounds often result in multiple infections with various kinds of bacteria and uncontrolled wound exudate, resulting in several healthcare issues. Advanced medicated nanofibres prepared by electrospinning have gained much attention for their topical application on infected chronic wounds. The objective of this work is to enhance the critical variables of ciprofloxacin-loaded polycaprolactone-silk sericin (PCL/SS-PVA-CIP) nanofibre production via the process of electrospinning. To examine the antibacterial effectiveness of PCL/SS-PVA-CIP nanocomposites, the material was tested against P. aeruginosa and S. aureus. The combination of PCL/SS-PVA-CIP exhibited potent inhibitory properties, with the most effective concentrations of ciprofloxacin (CIP) being 3 μg/g and 7.0 μg/g for each bacterium, respectively. The biocompatibility was evaluated by conducting cell reduction and proliferation studies using the human epidermal keratinocyte (HaCaT) cells and human gingival fibroblasts (HGFs) in vitro cell lines. The PCL/SS-PVA-CIP showed good cell compatibility with HaCaT and HGF cells, with effective proliferation even at antibiotic doses of up to 7.0 μg/g. The drug release effectiveness of the nanocomposites was assessed at various concentrations of CIP, resulting in a maximum cumulative release of 76.5% and 74.4% after 72 h for CIP concentrations of 3 μg/g and 7 μg/g, respectively. In summary, our study emphasizes the possibility of combining silk sericin (SS) and polycaprolactone (PCL) loading with CIP nanocomposite for wound management.

Takayasu arteritis (TA) is a chronic large-vessel vasculitis characterized by immune-mediated panarteritis, which predominantly affects the aorta and its main branches and is most prevalent in young women. TA is unusually associated with the presence of antiphospholipid antibodies. We present a case report of a 48-year-old Caucasian woman with acute aortic dissection as an initial feature of TA, where detailed clinical, imaging and laboratory studies were performed. Computed tomography angiography (CTA) of the chest and abdomen revealed aortic dissection DeBakey I. Bentall and De Bono surgery was performed. Additional immunological tests revealed positive antineutrophil cytoplasmic antibodies (ANCAs) with the simultaneous presence of pANCA and cANCA antibodies on indirect immunofluorescence, along with anti-MPO+PR3+antibodies positivity in the absence of a clinically relevant disease. Surprisingly, antiphospholipid antibodies (aPLs) were detected. Then, we performed a thorough review of the current literature. The coexistence of aPL antibodies and dual specificity for MPO and PR3 in a patient diagnosed with Takayasu arteritis is unusual and poses a diagnostic challenge. The presented case report outlines a rare case of aortic dissection as a presenting symptom of TA, along with atypical ANCA positivity and positive APL antibodies.

This study proposes a theoretical method for evaluating the “safety against derailment” indicator of a specialized train composition for the transportation of very long rails. A composition of nine wagons, suitable for the transportation of rails with a length of 120 m in three layers, is considered. For the remaining recommended rail lengths, the number of wagons is reduced or increased, with the calculation model being modified depending on the required configuration. When the composition is in a curve with the minimum radius (R = 150 m), the rails bend, and some of them come into contact with the vertical stanchions of the wagon and cause additional lateral forces. These forces are then transferred through the wagon body, central pivot, bogie frame, and wheels and act on the wheel–rail contact points. They could potentially lead to derailment of the train composition. The goal of this study is to determine the additional lateral forces that arise because of the bent rails. For the purposes of this study, the finite element method was used. Based on the displacements of the support points of the rails (caused by the geometry of the curve), the bending line of the elastic load is determined and the forces in the supports are calculated. The resulting forces are considered when determining the derailment safety criterion. The analysis of the results shows that the wagon with fixing blocks is the most at risk of derailment. The front and intermediate wagons have criterion values very close to that of the empty wagon. This shows that the emerging horizontal elastic forces do not significantly influence the derailment process. The obtained results show that the transportation of long rails with specialized train composition can be realized on four layers. This will significantly increase the efficiency of delivering new long rails.

The management strategy requires a shift to change-oriented management. These management approaches are process- and activity-oriented and are based on the assumption that the future is difficult to predict and ineffective for modeling. The aim of this study is to present a model of food safety management using a process approach based on the PDCA cycle set in the international standard ISO 22000:2018 by supplementing the regulatory requirements for food safety management. After analyzing the aspects of food safety management, a model is proposed for risk analysis and assessment at the operational and organisational level. In this study, the FMEA method for risk assessment of storage of foods of plant origin was used. The research can be useful for producers and traders in the planning and development of food safety management systems according to the requirements of the ISO 22000:2018 standard. The implementation of documented rules for compliance with the requirements of the international standard is aimed at the management and control of processes at the operational and organisational level in the activities of companies. Process management and data analysis is a direction to improve activities aimed at minimizing food safety risks.

The assessment of safety against freight wagons’ derailment is a mandatory element of the documents provided to the EU notifying authorities of the entry into service of new freight wagons. The assessment methodology is presented in EN 14363:2019. It is mainly aimed at the experimental measurement of certain parameters, and the data are used to calculate the safety criterion. The practical implementation of the tests is accompanied by many difficulties: finding a track with a proper radius, ensuring free access to the railway infrastructure for a long period of time, waiting for suitable metrological conditions, preparing the curve and the test wagon, etc. These difficulties are well known to the European legislators, and as a solution, they propose a large set of reference wagons that have undergone real tests. It is sufficient to demonstrate that the parameters of the new wagon relate to some of the reference wagon parameters to avoid such a requirement. Proving the “convergence” of the parameters of the new and the reference wagons is a lengthy, complex, and, in many cases, subjective process. To introduce an objective assessment, the authors set themselves the task of developing a theoretical method to assess safety against derailment.

(1) Background: Primary implant stability is vital for successful implant therapy. This study explores the influence of implant shape, length, and diameter on primary stability in different bone qualities. (2) Methods: Three implant systems (two parallel-walled and one tapered) with various lengths and diameters were inserted into polyurethane foam blocks of different densities (35, 25, 15, and 10 PCF) using standard drilling protocols. Primary stability was assessed through insertion torque (IT) and resonance frequency analysis (RFA). Optimal ranges were defined for IT (25 to 50 Ncm) and RFA (ISQ 60 to 80). A comparison of implant groups was conducted to determine adherence to the optimal ranges. (3) Results: Implant macro-design, -length, and -diameter and bone block density significantly influenced IT and RFA. Optimal IT was observed in 8/40 and 9/40 groups for the parallel-walled implants, while the tapered implant achieved optimal IT in 13/40 groups (within a 25–50 Ncm range). Implant diameter strongly impacted primary stability, with sufficient stability achieved in only one-third of cases despite the tapered implant’s superiority. (4) Conclusions: The findings highlight the need to adapt the drilling protocol based on diverse bone qualities in clinical practice. Further investigations should explore the impact of these adapted protocols on implant outcomes.

This paper aims to assess land use and land use change (LULC). For this purpose, supervised mapping on satellite imagery, using the European Space Agency (ESA) SNAP programme from LANDSAT databases, publicly accessible through the European Copernicus portal, was used. At the same time, an analysis of the degree of landscape fragmentation in the study area was carried out, which revealed that, because of the particular fragmentation of small polygons, the best results were obtained via analysis/supervised mapping on satellite images. This method, once validated in the field, reflects the most accurate land use pattern in the analysed area, with wide applications in studies of agriculture, biodiversity, geography, etc. Between 2000 and 2010, significant changes were registered. Artificial surfaces decreased by approximately 400 ha, showing a negative trend in the last period of the interval. Coniferous forests reached their maximum threshold in 2000 (with 114,400 ha) in conjunction with the “Grassland” class, which exceeded 16,700 ha. In 2010, a drastic decrease in “Grassland” was recorded, reaching half of the values of 1990 and 2000, now having only 15,684 ha. Land cover changes were significant when comparing the period before 1989 with 2021. This fact was due to socio-economic changes in society, in large part caused by changes in professions and the way of life of the population.

We consider the propagation of electromagnetic waves in the Friedmann–Lemaître–Robertson–Walker metric. The exact solutions for plane and spherical wave are written down. The corresponding redshift, amplitude change, and dispersion are discussed. We also speculate about the connection of the electromagnetic wave equation to the Proca equation and its significance for the early Universe.

The objective of this study was to evaluate the impacts of different sandblasting procedures in acid etching of Ti6Al4V surfaces on osteoblast cell behavior, regarding various physicochemical and topographical parameters. Furthermore, differences in osteoblast cell behavior between cpTi and Ti6Al4V SA surfaces were evaluated. Sandblasting and subsequent acid etching of cpTi and Ti6Al4V discs was performed with Al2O3 grains of different sizes and with varying blasting pressures. The micro- and nano-roughness of the experimental SA surfaces were analyzed via confocal, atomic force and scanning electron microscopy. Surface free energy and friction coefficients were determined. hFOB 1.19 cells were seeded to evaluate adhesion, proliferation and osteoblastic differentiation for up to 12 d via crystal violet assays, MTT assays, ALP activity assays and Alizarin Red staining assays. Differences in blasting procedures had significant impacts on surface macro- and micro-topography. The crystal violet assay revealed a significant inverse relationship between blasting grain size and hFOB cell growth after 7 days. This trend was also visible in the Alizarin Red assays staining after 12 d: there was significantly higher biomineralization visible in the group that was sandblasted with smaller grains (F180) when compared to standard-grain-size groups (F70). SA samples treated with reduced blasting pressure exhibited lower hFOB adhesion and growth capabilities at initial (2 h) and later time points for up to 7 days, when compared to the standard SA surface, even though micro-roughness and other relevant surface parameters were similar. Overall, etched-only surfaces consistently exhibited equivalent or higher adhesion, proliferation and differentiation capabilities when compared to all other sandblasted and etched surfaces. No differences were found between cpTi and Ti6Al4V SA surfaces. Subtle modifications in the blasting protocol for Ti6Al4V SA surfaces significantly affect the proliferative and differentiation behavior of human osteoblasts. Surface roughness parameters are not sufficient to predict osteoblast behavior on etched Ti6Al4V surfaces.

The Urals and Siberian vacuum residues are considered difficult to process in the ebullated bed hydrocracking because of their increased tendency to form sediments. Their achievable conversion rate reported in the literature is 60%. Intercriteria analysis was used to assess data from a commercial vacuum residue hydrocracker during processing blends from three vacuum residues: Urals, Siberian Light, and Basra Heavy. The analysis revealed that the main contributors to conversion enhancement is hydrodemetallization (HDM) and the first reactor ΔT augmentation. The increase of HDM from 40 to 98% and the first reactor ΔT (ΔT(R1)) from 49 to 91 °C were associated with a vacuum residue conversion enhancement of 62.0 to 82.7 wt.%. The developed nonlinear regression prediction of conversion from HDM and ΔT(R1) suggests a bigger influence of ΔT(R1) enhancement on conversion augmentation than the HDM increase. The intercriteria analysis evaluation revealed that the higher first reactor ΔT suppresses the sediment formation rate to a greater extent than the higher HDM. During processing Basrah Heavy vacuum residue, a reduction in hydrodeasphaltization (HDAs) from 73.6 to 55.2% and HDM from 88 to 81% was observed. It was confirmed that HDM and HDAs are interrelated. It was found that the attainment of conversion of 80 wt.% and higher during processing Urals and Siberian Light vacuum residues is possible when the HDM is about 90% and LHSV ≤ 0.19 h−1.

An optimization model for traffic light control in an urban network of intersections is derived. The model is based on store-and-forward analytic relations, which account for the length of the queue of waiting vehicles in front of the traffic light intersection. The model is complicated with probabilistic relations that formalize the requirements for maintaining short queues of vehicles. Probabilistic inequalities apply to each intersection of the city network. Approximations of probability inequalities are given in the article. Quadratic deterministic inequalities, which are part of the set of the traffic flow control optimization problem, are derived. Numerical simulations are performed, applying mean estimated data for real traffic in an urban area of Sofia. The model predictive approach is applied to traffic light optimization and control. Empirical results give advantages of the obtained model compared to the classical store-and-forward optimization model for the total number of vehicles waiting in the considered urban network.

An algorithm is derived for active business management. The key component of the algorithm is the definition and solution of an appropriate portfolio problem. For the last one, the disbursements for the business management are regarded as potential portfolio resources. For the portfolio definition, the increases or decreases of the disbursements are assumed to be the assets, whose weights are found as solutions from the portfolio optimization problem. These solutions recommend the reallocation of the resources between different disbursements, which increases the income of the business entity. The definition and solution of this portfolio problem are made sequentially in time, and the obtained solutions are applied as recommendations for future business management steps. An algorithm for business management, based on the sliding mode of repetitive definitions and solutions of portfolio problems with historical data of last disbursements, gives recommendations for the reallocation of resources for the next future period of management. The algorithm is numerically tested with real data on animal husbandry from Bulgaria. The empirical results demonstrate an advantage in increasing the husbandry income in comparison with the lack of such an active business policy. The algorithm can be implemented as a software solution in an appropriate programming system, supporting fintech service for active business management.

The Danube River has a large hydrographical basin, being the second largest river in Europe. The main channel flows through seven European countries with many species of fish inhabiting it. In this review we focused on the invasive species silver carp (Hypophthalmichthys molitrix), which plays an important ecological and economic role in its original habitat, but since introduced in Europe’s rivers, the species has posed a serious ecological risk under global warming. In this review paper, we gathered data regarding silver carp, such as when and how it entered the Danube Delta and the water temperature suitable for its growth and reproduction, mainly in the context of global warming, as well as the nature of nutrition and the ecological risk the species poses.

Sound affects the medium it propagates through and studies on biological systems have shown various properties arising from this phenomenon. As a compressible media and a “collective mirror”, water is influenced by all internal and external influences, changing its molecular structure accordingly. The water molecular structure and its changes can be observed as a whole by measuring its electromagnetic (EMG) spectrum. Using near-infrared spectroscopy and aquaphotomics, this pilot study aimed to better describe and understand the sound-water interaction. Results on purified and mineral waters reported similar effects from the applied 432 Hz and 440 Hz frequency sound, where significant reduction in spectral variations and increased stability in water were shown after the sound perturbation. In general, the sound rearranged the initial water molecular conformations, changing the samples’ properties by increasing strongly bound, ice-like water and decreasing small water clusters and solvation shells. Even though there was only 8 Hz difference in applied sound frequencies, the change of absorbance at water absorbance bands was specific for each frequency and also water-type-dependent. This also means that sound could be effectively used as a perturbation tool together with spectroscopy to identify the type of bio, or aqueous, samples being tested, as well as to identify and even change water functionality.

Background: This study examines the relationship between the presence of crystals in the synovial fluid of patients with psoriatic arthritis (PsA) and disease activity. Methods: The synovial fluid of 156 PsA patients was analyzed and compared to 50 patients with gonarthrosis (GoA). The Leica DM4500P polarization microscope was used for crystal detection. Results: The presence of crystals was observed in 23.71% of PsA patients and none of the GoA patients, p < 0.001. Monosodium urate crystals (67.58%) and calcium pyrophosphate crystals (21.62%) were prevalent. The presence of crystals in the synovial fluid of PsA patients was associated with high disease activity according to the Composite Psoriatic Disease Activity Index (OR = 18.75, 95%; CI: 7.13 to 49.25) and the Disease Activity for Psoriatic Arthritis (OR = 15.96, 95%; CI: 5.76 to 44.23), with severe disability according to the Health Assessment Questionnaire Disability Index (OR = 13.60, 95%; CI: 5.09 to 36.31), and with severe pain on the Visual Analog Scale (OR = 157.25, 95%; CI: 39.50 to 625.94). Conclusion: Our results suggest that synovial fluid examination should be included in the treatment pathway for PsA patients with active disease, to aid in determining whether urate-lowering therapy is required.

A bi-level model for traffic signal optimization is developed. The model predictive framework is applied for traffic control in an urban traffic network. The potential of the bi-level formalization is used to increase the space of control influences with simultaneous evaluation of the green light and cycle durations. Thus, the increased control space allows more traffic parameters to be considered, such as vehicles queues and traffic flows. A particular modification of the bi-level control is applied for the synchronization of the traffic lights in the network. The model predictive approach is used for the real-time management of the traffic in the network. The control implementations are constrained by the shortest evaluated cycle. Thus, a synchronization of the traffic lights is applied for the minimization of the queues and maximization of the outgoing flows from the network. The bi-level model has been numerically tested on a set of intensive crossroads in Sofia. The numerical simulations prove the superiority of the developed bi-level control in comparison with the classical optimization of queue lengths.

This study aims to analyze and compare the disease activity control and quality of life of patients with rheumatoid arthritis (RA) who were treated with biological products in real-life settings. We tried to determine whether there is a symmetry in the performance of the biological molecules between each other and with the first Janus kinase (JAK) inhibitor. This is an observational, longitudinal, real-life study performed in the biggest rheumatology clinic during the period 2012–2020 comparing quality of life, cost of therapy, and disease control via different clinical measures. In all three disease activities measurement instruments, we observed an improvement for all biologic and target synthetic medicines. The disease activity score (DAS28) score decreased from 5.06 to 3.01, on average, for all INNs, suggesting that the majority of patients move away from moderate to low disease activity. The clinical disease activity index (CDAI) score decreased from 25.9 to 9.4, also indicating that patients with moderate disease activity reached a low level of activity. Similar results are reflected in the score, which fell from 27.7 to 10.3, again confirming the improvement to a low level of disease activity for patients treated with all INNs. Logically, with the successful control of disease activity, the quality of life (QoL) of the observed patients improved from 0.77 to 0.83 after a one-year follow up, as measured with the EuroQuol 5D-3L (EQ5D). Based on these results, we can consider that the observed biological INNs perform symmetrically in terms of the control of disease activity and improvement in the QoL of the observed patients. Biological therapy improves the disease control and quality of life of suitable patients with RA in real-life settings. All available biological therapies could be used interchangeably.

Introduction. Ovarian carcinosarcoma (OCS), also known as malignant mixed Müllerian tumour (MMMT), is one of the rarest histological subtypes of ovarian cancer. It is an aggressive tumour with a dismal prognosis—the median survival of patients is less than two years. The rarity of the disease generates many controversies about histogenesis, prognostic factors and treatment of OCS. Histologically, OCS is composed of an epithelial and sarcomatous component. Case report. In the present case, a patient with bilateral ovarian cysts and bulky paraaortic lymph nodes is reported. Retroperitoneal paraaortic lymph node metastases were the only extrapelvic dissemination of OCS. The patient underwent comprehensive surgical staging procedures, including total abdominal hysterectomy and bilateral salpingo-oophorectomy, supracolic omentectomy and selective para-aortic lymphadenectomy. Histologically the ovarian carcinosarcoma was composed of an epithelial component (high-grade serous adenocarcinoma) and three sarcomatous components (homologous—endometrial stromal cell sarcoma, and heterologous—chondrosarcoma, rhabdomyosarcoma). Immunohistochemistry staining was performed. A postoperative complication (adhesion between the abdominal aorta and terminal ileum causing obstructive ileus) that has never been reported in the medical literature occurred. Conclusion. Carcinosarcomas are carcinomas with epithelial–mesenchymal transition and heterologous differentiation. Retroperitoneal pelvic and paraaortic lymph nodes should be carefully inspected in patients with ovarian tumours. Adhesions between the small bowels and abdominal aorta are possible complications after lymph node dissection in the paraaortic region.

In a recent work, we demonstrated that a modified gravity model in which a scalar “darkon” field is coupled to both the standard Riemannian metric and to another non-Riemannian volume form is compatible with observational data from Supernovae Type Ia. Here, we investigate a more complicated model with an additional “inflaton” scalar field. We demonstrate numerically that the model can qualitatively reproduce the Universe inflation epoch, matter dominated epoch, and present accelerating expansion in a seamless way. We show that such solutions occur only when the model parameters are within a very particular range. The main numerical problem we are faced with is reproducing the extremely small time of the inflation epoch. Here, we present how the variation of some parameters affects this time.