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Srdjan Živanović, Jelena Pavlović, N. Hadživuković, Sandra Matović, Olivera Kalajdžić, Bojana Vuković, Ljubiša Kucurski

<p><strong>Introduction.</strong> With the development of medical and health sciences, research problems have become more complex, and relying solely on quantitative or qualitative research approaches is no longer sufficient. The aim of this paper was to map the progress and trends in the scientific literature regarding the application of mixed studies in medical and health sciences.</p> <p><strong>Methods.</strong> Bibliometric analysis was applied to meet the established goals. The Dimensions database was selected for literature search. The analysis unit consisted of 485 publications of various types, and the VosViewer program was employed for the analysis.</p> <p><strong>Results. </strong>The results have shown that this topic in science has experienced an exponential decline in the last year. Additionally, the most productive authors, journals, and countries have been identified, along with their collaborative networks through visual co-citation analysis. Based on the analysis of word co-occurrence, we can conclude that words like &ldquo;combined studies,&rdquo; &ldquo;problem,&rdquo; &ldquo;factors,&rdquo; &ldquo;community&rdquo; are most frequently repeated, indicating that the topics addressed in this domain mainly focus on investigating and addressing numerous issues in the field of medical and health sciences.</p> <p><strong>Conclusion. </strong>Although the results indicate a decreased interest in this topic in the last year, it does not diminish the significance of this research. Progress in medical and health sciences requires a comprehensive approach to research, which includes both quantitative and qualitative methods, such as mixed studies. Understanding the current trends and available resources for researchers assists in achieving better outcomes and improving the quality of healthcare practice.</p>

N. Hadživuković, Jelena Pavlović, Srdjan Živanović, Sandra Matović, S. Mašić, Dragan Spaic, Olivera Kalajdžić, Ljubiša Kucurski et al.

<p><strong>Introduction. </strong>Frailty is common in elderly persons and carries a high risk of poor health outcomes, including increased mortality, institutionalization, falls, and hospitalization. The aim of the work was to determine the risk factors for frailty in elderly persons.</p> <p><strong>Methods. </strong>The research was conducted in Bijeljina and Foča, in the period from February to June 2022, and was approved by the Ethics Committee of the Faculty of Medicine in Foča. A total of 243 respondents over the age of 65 took part in the research. When it comes to the instruments, the sociodemographic questionnaire, the EQ-5D-5L health questionnaire, the general sarcopenia rapid screening questionnaire SARC-F and the Kessler scale for the assessment of psychological distress were used.</p> <p><strong>Results.</strong> There were 43.6% of males and 56.4% of females participating in the research. One quarter (25%) of respondents evaluated their health as weak. Sarcopenia was identified in 28% of respondents, while 18.1% had a moderate and 11.9% a serious disorder in the field of psychological distress.</p> <p><strong>Conclusion. </strong>The presence of psychological distress and sarcopenia in a high percentage, as well as weak health status in the people over 65, is evident, which represents potential risk factors for frailty.</p>

Tarik Kazaz, Karan Jayachandra, Arie Koppellar, Yiting Lu

In FMCW automotive radar applications, it is often a challenge to design a chirp sequence that satisfies the requirements set by practical driving scenarios and simultaneously enables high range resolution, large maximum range, and unambiguous velocity estimation. To support long-range scenarios the chirps should have a sufficiently long duration compared to their bandwidth. At the same time, the long chirps result in ambiguous velocity estimation for targets with high velocity. The problem of velocity ambiguity is often solved by using multiple chirp sequences with co-prime delay shifts between them. However, coherent processing of multiple chirp sequences is not possible using classical spectral estimation techniques based on Fast Fourier Transform (FFT). This results in statistically not efficient velocity estimation and loss of processing gain. In this work, we propose an algorithm that can jointly process multiple chirp sequences and resolve possible ambiguities present in the velocities estimates. The resulting algorithm is statistically efficient, and gridless. Furthermore, it increases the resolution of velocity estimation beyond the natural resolution due to its super-resolution properties. These results are confirmed by both numerical simulations and experiments with automotive radar IC.

Bridge crane is exposed to dynamic loads during its non-stationary operations (acceleration and braking). Analyzing these operations, one can determine unknown impacts on the dynamic behavior of bridge crane. These impacts are taken into consideration using selected coefficients inside the dynamic model. Dynamic modelling of a bridge crane in vertical plane is performed in the operation of the hoist mechanism. The dynamic model is obtained using data from a real bridge crane system. Two cases have been analyzed: acceleration of a load freely suspended on the rope when it is lifted and acceleration of a load during the lowering process. Physical quantities that are most important for this research are the values of stress and deformation of main girders. Size of deformation at the middle point of the main crane girder is monitored and analyzed for the above-mentioned two cases. Using the values of maximum deformation, one also obtains maximum stress values in the supporting construction of the crane.

. The progress of additive manufacturing technology brings about many new questions and challenges. Additive manufacturing technology allows for designing machine elements with smaller mass, but at the same time with the same stiffness and stress loading capacity. By using additive manufacturing it is possible to produce gears in the form of shell shape with infill inside. This study is carried out as an attempt to answer the question which type of infill, and with how much density, is optimal for a spur gear tooth to ensure the best stiffness and stress loading capacity. An analysis is performed using numerical finite element method. Two new infill structures are proposed: triangular infill with five different densities and topology infill designed according to the already known results for 2D cantilever topology optimization, known as Michell structures. The von Mises stress, displacements and bending stiffness are analyzed for full body gear tooth and for shell body gear tooth with above mentioned types of infill structure.

A. Abdelhak, P. Benkert, S. Schaedelin, W. Boscardin, C. Cordano, J. Oechtering, Kirtana Ananth, C. Granziera et al.

Importance Mechanisms contributing to disability accumulation in multiple sclerosis (MS) are poorly understood. Blood neurofilament light chain (NfL) level, a marker of neuroaxonal injury, correlates robustly with disease activity in people with MS (MS); however, data on the association between NfL level and disability accumulation have been conflicting. Objective To determine whether and when NfL levels are elevated in the context of confirmed disability worsening (CDW). Design, Setting, and Participants This study included 2 observational cohorts: results from the Expression, Proteomics, Imaging, Clinical (EPIC) study at the University of California San Francisco (since 2004) were confirmed in the Swiss Multiple Sclerosis Cohort (SMSC), a multicenter study in 8 centers since 2012. Data were extracted from EPIC in April 2022 (sampling July 1, 2004, to December 20, 2016) and SMSC in December 2022 (sampling June 6, 2012, to September 2, 2021). The study included 2 observational cohorts in tertiary MS centers. All participants of both cohorts with available NfL results were included in the study, and no eligible participants were excluded or declined to participate. Exposure Association between NfL z scores and CDW. Main Outcome Measures CDW was defined as Expanded Disability Status Scale (EDSS) worsening that was confirmed after 6 or more months and classified into CDW associated with clinical relapses (CDW-R) or independent of clinical relapses (CDW-NR). Visits were classified in relation to the disability worsening events into CDW(-2) for 2 visits preceding event, CDW(-1) for directly preceding event, CDW(event) for first diagnosis of EDSS increase, and the confirmation visit. Mixed linear and Cox regression models were used to evaluate NfL dynamics and to assess the association of NfL with future CDW, respectively. Results A total of 3906 EPIC visits (609 participants; median [IQR] age, 42.0 [35.0-50.0] years; 424 female [69.6%]) and 8901 SMSC visits (1290 participants; median [IQR] age, 41.2 [32.5-49.9] years; 850 female [65.9%]) were included. In CDW-R (EPIC, 36 events; SMSC, 93 events), NfL z scores were 0.71 (95% CI, 0.35-1.07; P < .001) units higher at CDW-R(-1) in EPIC and 0.32 (95% CI, 0.14-0.49; P < .001) in SMSC compared with stable MS samples. NfL elevation could be detected preceding CDW-NR (EPIC, 191 events; SMSC, 342 events) at CDW-NR(-2) (EPIC: 0.23; 95% CI, 0.01-0.45; P = .04; SMSC: 0.28; 95% CI, 0.18-0.37; P < .001) and at CDW-NR(-1) (EPIC: 0.27; 95% CI, 0.11-0.44; P < .001; SMSC: 0.09; 95% CI, 0-0.18; P = .06). Those findings were replicated in the subgroup with relapsing-remitting MS. Time-to-event analysis confirmed the association between NfL levels and future CDW-R within approximately 1 year and CDW-NR (in approximately 1-2 years). Conclusions and Relevance This cohort study documents the occurrence of NfL elevation in advance of clinical worsening and may hint to a potential window of ongoing dynamic central nervous system pathology that precedes the diagnosis of CDW.

E. Canales-Rodríguez, M. Pizzolato, Feng-Lei Zhou, M. Barakovic, Jean-Philippe Thiran, Derek K. Jones, Geoffrey J. M. Parker, T. Dyrby

This study aims to evaluate two distinct approaches for fiber radius estimation using diffusion‐relaxation MRI data acquired in biomimetic microfiber phantoms that mimic hollow axons. The methods considered are the spherical mean power‐law approach and a T2‐based pore size estimation technique.

SAŽETAK Perfuzija se odnosi na isporuku kiseonika i hranljive materije u tkiva putem protok krvi i jedan je od najosnovnijih fiziološki parametri. Poremećaji perfuzije takođe čine većinu vodeći uzroci medicinskog invaliditeta i mortalitet. Dok mjerenja od perfuzije imaju direktnu dijagnostičku vrijednost u vaskularni poremećaji, mjerenja perfuzije takođe služe kao biomarkeri za a širi spektar fizioloških i patofizioloških funkcije. Bliska sprega između cerebralnog krvotoka i metabolizma omogućava regionalnu funkciju mozga biti procijenjen mjerenjima od cerebralnu perfuziju i povećanu vaskularnost neoplazmi omogućava perfuziju tumora da se koristi kao mjera tumora stepena i za praćenje odgovora na tumor terapija. U oblasti MRI, najviše ljudi povezuju pojam perfuzije snimanje s dinamičkim kontrastom osjetljivosti snimanje pomoću kontrasta za opuštanje agent. ASL Perfuzija je tehnika MR perfuzije koja ne zahtjeva intravensku primjenu kontrastnog sredstva ( za razliku od DSc I DCE perfuzije). Umjesto toga, koristi sposobnost MRI-a da magnetski označi arterijsku krv. Parametar koji se najčešče izvodi je cerebralni protok krvi (CBF). ASL je vrlo pogodna tehnika za upotrebu u pedijatriji, u kojoj upotreba radioaktivnih tragova moze biti ograničena. Također je sigurna metoda za primjenu kod pacijenata sa oštečenom bubrežnom funkcijom.

H. Zechmeister, Leonie Möslinger, A. Korjenic, Erich Streit, Abdulah Sulejmanovski, Patrick Niklas Frank, Esther Hummel

There is an increasing demand for green plant walls in indoor environments because of their multifaced benefits, such as aesthetic appeal, indoor air quality improvement, or psychological well-being. Mosses are believed to be excellent for these walls due to their easy application and maintenance. However, so far there is no evidence for their indoor survival. In this study, we tested the moss species Hypnum cupressiforme, Bryachythecium rutabulum, Eurrhynchium angustirete, Thuidium tamariscinum, Streblotrichum convolutum, Syntrichia ruralis, and Ceratodon purpureus for indoor use in living moss walls. We evaluated their vitality through the monitoring of leaf coloration over a twelve month period, subjecting them to varying temperature ranges (14–20 °C), humidity levels (60–100%), and diverse irrigation methods (drip and spray irrigation, 300–1500 mL per day) within controlled climate chambers. Depending on the combination of these variables, mosses survived up to six months. Hypnum cupressiforme and Ceratodon purpureus performed best. However, as the time span of survival was limited, the use of living mosses for indoor purposes at the current stage cannot be recommended. An additional problem is that the requisition of living material such as in the culturing of moss under horticultural conditions is difficult and harvesting from natural environments is detrimental to most habitats.

M. Beyeler, Erich Rea, L. Weber, N. Belachew, Enrique Barvulsky Aleman, M. Kielkopf, C. Kurmann, L. Grunder et al.

Background The absence of the susceptibility vessel sign (SVS) in patients treated with mechanical thrombectomy (MT) is associated with poor radiological and clinical outcomes after 3 months. Underlying conditions, such as cancer, are assumed to influence SVS status and could potentially impact the long-term outcome. We aimed to assess SVS status as an independent predictor of long-term outcomes in MT-treated patients. Methods SVS status was retrospectively determined in consecutive MT-treated patients at a comprehensive stroke center between 2010 and 2018. Predictors of long-term mortality and poor functional outcome (modified Rankin Scale (mRS) ≥3) up to 8 years were identified using multivariable Cox and logistic regression, respectively. Results Of the 558 patients included, SVS was absent in 13% (n=71) and present in 87% (n=487) on baseline imaging. Patients without SVS were more likely to have active cancer (P=0.003) and diabetes mellitus (P<0.001) at the time of stroke. The median long-term follow-up time was 1058 days (IQR 533–1671 days). After adjustment for active cancer and diabetes mellitus, among others, the absence of SVS was associated with long-term mortality (adjusted HR (aHR) 2.11, 95% CI 1.35 to 3.29) and poor functional outcome in the long term (adjusted OR (aOR) 2.90, 95% CI 1.29 to 6.55). Conclusion MT-treated patients without SVS have higher long-term mortality rates and poorer long-term functional outcome. It appears that this association cannot be explained by comorbidities alone, and further studies are warranted.

A. Mujanović, C. Kurmann, Michael Manhart, E. Piechowiak, S. Pilgram-Pastor, B. Serrallach, G. Boulouis, T. Meinel et al.

Clinical utility and diagnostic sensitivity of new‐generation flat‐panel computed tomography perfusion imaging (FPCTP) performed immediately after mechanical thrombectomy (MT) is unknown. We aimed to assess whether FPCTP obtained directly after MT could provide additional potentially relevant information on tissue reperfusion status. Qualitative, single‐center analysis of all consecutive acute stroke patients admitted between 06/2019 and 03/2021 who underwent MT and post‐interventional FPCTP (n=26). A core‐lab blinded to technical details and clinical data performed reperfusion grading on post‐interventional digital subtraction angiography (DSA) images and time‐sensitive FPCTP maps. All patients were classified according to agreement between DSA and FPCTP. In 10/26 patients FPCTP revealed new, potentially clinically relevant information. Core‐lab adjudicated dichotomized detection of hypoperfusion (present/absent) was concurring in 21/26 (81%) patients. Of these, reperfusion findings showed perfect agreement on location and size in 16 (62%) patients, while in 5 (19%) patients with incomplete reperfusion, FPCTP showed additional hypoperfused areas missed on DSA. Of the remaining five patients subject to disagreement regarding the presence or absence of hypoperfusion, three showed complete reperfusion on DSA but hypoperfusion was noted on FPCTP, whereas two showed incomplete reperfusion on DSA without detectable hypoperfusion on FPCTP. FPCTP findings could have avoided Thrombolysis in Cerebral Infarction (TICI) overestimation in all false‐positive operator‐rated TICI3 cases. In both core‐lab and real‐world operator assessment, FPCTP may provide additional clinically relevant information in a considerable percentage of patients undergoing MT. Hence, FPCTP may constitute a new standard for evaluating reperfusion efficacy and informed decision making in the angiography suite.

A. Mujanović, F. Ng, M. Branca, T. Meinel, Leonid Churilov, Peter J Mitchell, N. Yassi, M. Parsons et al.

The benefit of additional reperfusion attempts in patients with partial angiographic reperfusion (TICI2b) is unknown. The PROCEED model predicts subsequent favorable occurrence of complete reperfusion (i.e. delayed reperfusion [DR]) at 24 hours after initial incomplete angiographic reperfusion at the conclusion of thrombectomy. This study aims to externally validate the PROCEED model using pooled data from multiple international trials that systematically performed follow‐up perfusion imaging. Individual patient data for external validation were obtained from the EXTEND‐IA, EXTEND‐IA TNK part 1 and 2 trials (clinicaltrials.gov, unique‐identifier: NCT01492725, NCT02388061 and NCT03340493). The model’s primary outcome of interest was the occurrence of DR, defined as the absence of any focal perfusion deficit on follow‐up CT or MRI perfusion imaging maps, despite initial incomplete angiographic reperfusion on the final thrombectomy angiography series. The updated model’s performance was evaluated with discrimination, calibration and clinical decision curves. We analyzed 267 patients for the external validation, with median age of 74 (IQR 64 – 80), 44.2% were female and 62% had DR. The externally validated model had good discrimination (C‐statistic 0.81, 95% CI 0.72 – 0.86) and was well calibrated (intercept 0.22, 95% CI 0.18‐0.33 and slope 0.96, 95% CI 0.81‐1.23). With threshold probability of R=12% (i.e. 88% chance of having DR), pursuing additional reperfusion attempts to pursue complete angiographic reperfusion in a patient with high‐likelihood of DR were seven times worse (Cost:Benefit Ratio 1:7, Figure 1) than no further endovascular maneuver. In terms of standardized net reduction, the PROCEED model could reduce one in five unnecessary interventions without missing an intervention for any patient who would eventually have DR. Across a wide range of threshold probabilities, the model outperformed the scenario of the typical decision‐making process in the angiography suite, based on the current treatment guidelines. The externally validated model had good predictive accuracy and discrimination. Depending on the acceptable risk threshold, the model may compliment clinical judgment of the treating physicians and inform on natural progression of untreated incomplete reperfusion.

A. Greljo, J. Šalko, Aleks Smolkovič, P. Stangl

Exclusive semileptonic b hadron decays (b → uℓν) serve as a sandbox for probing strong and electroweak interactions and for extracting the CKM element Vub. Instead, this work investigates their underexplored potential to reveal new short-distance physics. Utilizing SMEFT as a conduit to chart territory beyond the SM, we demonstrate that substantive new physics contributions in b → uℓν are necessarily linked to correlated effects in rare neutral-current b decays, neutral B meson mixing or high-mass Drell-Yan tails. We find that measurements of the latter processes strongly restrict the allowed deviations in the former. A complete set of tree-level mediators, originating from a perturbative ultraviolet model and matching at dimension 6, is thoroughly explored to support this assertion. As a showcase application, we examine the feasibility of a new physics interpretation of the recent tension in exclusive |Vub| extraction from B → Vℓν where V = (ρ, ω).

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