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Cyclic up-down words
No full textA word of even length n is said to be cyclic up-down if . We find the generating function for the number of cyclic up-down words over {1, 2, . . . , k}, from which a closed-form formula is derived. We also construct a bijection with semi-magic labelings of certain graphs, called cycle-of-loops graphs
Sulfuric Acid Leaching оf Zinc Ferrite Residue
No full textZinc ferrite residue, a by-product from the hydrometallurgical processing of zinc calcine, contains significant amounts of zinc, iron, lead, copper, and silver, often locked in complex oxide and spinel phases. This study aims to characterize zinc ferrite residue using ICP-OES analysis, XRD, and SEM/EDS, and to evaluate its behavior during sulfuric acid leaching under controlled laboratory conditions. Thermodynamic modeling with HSC Chemistry software was used to construct Eh–pH diagrams and predict phase stability across different temperatures and redox conditions. The experimental results confirmed efficient leaching of zinc, copper and iron, while lead and silver were largely retained in the insoluble resi-due. These findings highlight the potential for selective zinc extraction and con-centration of lead and silver in the solid phase, offering a promising route for sus-tainable ZFR processing
Selective Dry Cow Therapy: economic, environmental, and regulatory perspectives
No full textMastitis remains one of the most economically important diseases in dairy farming. The aim of this review was to discuss the main ideas, practical benefits, economic impacts, rules and regulations, and environmental aspects of selective dry cow therapy (SDCT) as a means for managing udder health and antibiotic use. Interest is increasing in antimicrobial resistance, environmental pollution, and stronger regulations on antibiotic use in food production, so SDCT has become even more relevant in modern dairy herd management. This method involves selectively treating only cows or quarters at a high risk of intramammary infections at dry-off, mainly based on somatic cell count, clinical history of mastitis, or bacterial culture results. Evidence shows that when used correctly, SDCT can significantly reduce antibiotic use without compromising udder health, particularly if used with internal teat sealants. Economic analyses have indicated that SDCT can cut antibiotic-related costs by up to 50% while keeping mastitis under control, if protocols are followed properly. Global policies, such as the European Green Deal and One Health initiatives, encourage targeted antibiotic use to improve both animal health and environmental conservation in dairy farming. However, challenges still remain in implementation, including the risk of under-treatment, the need for accurate diagnostic tools, and ensuring farmer compliance with selection protocols. Advanced developments in precision dairy farming, such as automated testing and AI-assisted decision-making, have improved the feasibility and success of SDCT in different herd management systems
Koncentracija β-hidroksibutirata i broj somatskih stanica kao prevalencija subkliničke ketoze mliječnih krava
No full textThe aim of this study was to investigate the prevalence of subclinical ketosis in dairy cows based on elevated levels of milk β-hydroxybutyrate (BHB), somatic cell count (SCC), and oth¬er milk components. The analyzed data were obtained through routine analyses Dairy Herd Improvement (DHI) milk samples, by Fourier-transform infrared (FTIR) spectroscopy. The initial dataset included a total of 23,492 Holstein cow milk samples collected between January 2022 and January 2025 on six farms located in the Province of Vojvodina, Serbia. After outlier removal, final data set included 22,915 milk samples. Based on the concentration of β-hydroxy¬butyrate (BHB), 75 % of the samples were in the first negative group (BHB0.20 mmol/L) comprised 4 % of the samples, with an average concentration of 0.34 mmol/L. Through the analysis of the milk components, it was determined that in the first period, at 5-42 days in milk (DIM), significantly affected all observed parameters. The lactose content is decreasing, while fat, protein, total solids, milk fat/protein (F/P) ratio, SCC and urea are increasing. The results highlight the potential of using milk samples from Dairy Herd Improvement (DHI) programs to monitor elevated levels of milk BHB and SCC at the herd level. This approach may serve as a useful tool for estimating the prevalence of subclinical ketosis in dairy cows. Additionally, different BHB thresholds might be needed for different periods of lactation.Cilj istraživanja bio je istražiti prevalenciju i učinak povišene razine β-hidroksibutirata u mlijeku (BHB), SCC (broj somatskih stanica) i drugih komponenti sirovog mlijeka koje je detektirano rutinskom Fourier-transform infracrvenom (FTIR) analizom u uzorcima mlijeka. Skup podataka je prikupljen u razdoblju od siječnja 2022. do siječnja 2025. i prvobitno je brojao 23.492 uzoraka sirovog mlijeka od holstein krava sa 6 različitih farmi smještenih u Vojvodini, Srbija. Poslije uklanjanja ekstremnih vrijednosti, konačni skup podataka brojao je 22.915 uzoraka mlijeka. Prosječna prevalencija povišene koncentracije BHB u mlijeku za prvu negativnu skupinu (0,20 mmol/L) bilo je 4 % (prosječna BHB 0.34). Analizom sastava mlijeka utvrđeno je da je prvo razdoblje od 5-42 dana značajno utjecalo na sve promatrane parametre kvalitete mlijeka. Sadržaj laktoze se smanjuje, međutim, sadržaj proteina, ukupne suhe tvari, F/P, SCC i uree raste. Rezultati ističu potencijal korištenja uzoraka mlijeka iz programa za poboljšanje mliječnog stada (DHI) za praćenje povišenih razina BHB-a i SCC-a u mlijeku na razini stada. Ovaj pristup može poslužiti kao koristan alat za procjenu prevalencije subkliničke ketoze kod mliječnih krava. Osim toga, za različita razdoblja laktacije mogu biti potrebni različiti pragovi detekcije BHB-a
On the identification of a distribution for the arrivals to a queueing system: an application from bank data
No full textQueues are an integral part of life. The literature available concentrates on Poisson arrival and exponential service time. The present paper focuses on statistical inference on the parameters of queueing models. The work is data driven. The dataset considered is the queueing system in banks which is publicly available. The number of servers has been estimated for a steady state system. The data has been tested for normality. The goodness of fit test has been done for the arrival pattern, and it is found that the discrete analog of smallest extreme value distribution is a good fit to the data which is an alternative to the widely used Poisson distribution
First records of the invasive weed of Union Concern Cenchrus setaceus (Poaceae) in Crete (Greece)
No full textCenchrus setaceus (Forssk.) Morrone has been included in the list of invasive alien species of Union Concern (the EU list) since 2017. This means that the species can no longer be imported, cultivated, transported, commercialized, planted, or intentionally released into the environment in the whole of the European Union. Despite this, the species was recently found in the wild in Crete. The species was observed in 2024 along the route between the cities of Heraklion and Agios Nikolaos, i.e. over a distance of more than 60 kilometers. Research into the presence of the species in Crete revealed that it was also known to occur on the western side of the island (Chania area) from 2020 onwards. Given the relative extent of the species’ local distribution area, it appears that the species is either a recent, very rapidly expanding weed, or that it has been overlooked for several years. It is especially alarming that the species is currently still being planted in new green areas, both public and private, and is therefore apparently still available for sale in the local horticultural trade, despite EU regulations. Details of these first records, including a distribution map and new illustrations, are presented
The North American weed Amaranthus tuberculatus (Amaranthaceae) new to Portugal: previously overlooked or spreading rapidly?
No full textThe dioecious species Amaranthus tuberculatus (Moq.) J.D.Sauer, native to North America and a major weed of agricultural fields and riparian habitats, was discovered on the banks of the Tagus (Tejo) River in the late summer of 2024, apparently for the first time in Portugal. The species occurs here in exceptionally large numbers, with probably tens of thousands of plants, and in numerous locations on the sandy and gravelly banks of the river in the Ribatejo area, roughly between Azambuja and Azinhaga, over a distance of about 60 kilometers. It may also occur further upstream, where no prospecting has been carried out but where suitable habitats are also available. Considering its current distribution and the number of plants observed, the species has either been present in the region for a long time but has been overlooked (although no older observations could be found on e.g. GBIF or iNaturalist, not even under other amaranth species names), or it is indeed a recent introduction that is spreading very rapidly. However, it can certainly be considered an invasive species. Here, the current naturalized range of the species in Europe and the Mediterranean area is critically reevaluated. Although the species is known from relatively many countries, it is currently only naturalized with certainty in Israel, Italy, Croatia, Serbia and now Portugal. The species is described and illustrated and a local distribution map is presented; notes on its ecology are also given
Risk-based decision-making: extended F-Entropy method with correction factor based 2D-FAHP method
Get PDFIn complex decision-making processes using multi-criteria decision-making methods, experts' beliefs and judgments, as well as their knowledge, are influential in the comparisons between criteria and alternatives, which may lead to overlapping importance rankings of criteria. In this study, to increase the degree of representativeness of uncertainties in overlapping criteria evaluations, a correction term is integrated into the fuzzy entropy method, so that the risk cost levels of the main criteria of equal importance differ according to the number of sub-criteria. The integrated correction term into the fuzzy entropy calculation is proposed as a relative importance weight multiplier in the two-dimensional fuzzy AHP process steps. Although the -alpha truncation method is proposed for the Fuzzy AHP method, the decision matrix is converted into crisp values in the process stages and directly reduced to the Classical AHP method. Within this article, using the judgment matrix with interval values is proposed instead of exact judgment values as to not distort the fuzzy structure of the result values. In the article, the two-dimensional fuzzy Entropy weights obtained by using the alpha-cutting method can be used as a relative importance weight multiplier in the fuzzy AHP process proposed in two dimensions to obtain clear importance rankings of the criteria. Thanks to the method approach proposed, OCTAVE Allegro logic is combined to create a relative risk matrix according to the risk environment conditions for the criteria alongside the ranking level
Molecular and morphological characterization of diatoms related to dense mucilage formation in Turkish coastal waters
Get PDFCryptic diatom species, despite their subtle morphological traits, play a pivotal role in harmful algal blooms (HABs) and mucilage formation, making their identification a critical challenge. This study combines molecular and morphological approaches to characterize diatom species associated with the extensive mucilage observed in Turkish coastal waters between 2020 and 2021. Among the findings, Minutocellus polymorphus (Hargraves & Guillard) Hasle, Stosch & Syvertsen and Fistulifera saprophila (Lange-Bertalot & Bonik) Lange-Bertalot whose molecular phylogenetic analysis was carried out by sequencing small subunit ribosomal DNA (SSU rDNA) and internal transcribed spacer (ITS), are reported for the first time in Turkish waters, expanding our understanding of local biodiversity. Additionally, Pseudo-nitzschia pungens (Grunow ex Cleve) G.R.Hasle was molecularly characterized for the first time in the Sea of Marmara using large subunit ribosomal DNA (LSU rDNA) and ITS sequences. These results underscore the indispensable role of molecular techniques in uncovering the hidden diversity of diatoms and their potential contribution to HABs and mucilage events. By linking these findings to the ongoing mucilage phenomenon, this study offers significant insights into the ecological dynamics of the Sea of Marmara and highlights the need for integrative approaches in future research
PROCJENA IZVEDIVOSTI FOTOGRAMETRIJE ZA PODZEMNI RUDARSKI MONITORING: SIMULACIJSKA STUDIJA
No full textUnderground mining operations face significant challenges in monitoring structural stability and safety due to limited visibility and access. This study evaluates the feasibility of photogrammetry for underground mine monitoring using a simulation-based framework, bypassing resource-intensive field experiments. Synthetic datasets, generated via Blender and MATLAB, were used to assess photogrammetric accuracy, scalability, and limitations under varying lighting (25–100 lux), noise, and dust conditions. Three Structure-from-Motion (SfM) algorithms – COLMAP, OpenMVG, and Agisoft Metashape – were compared to evaluate performance robustness. The results indicate a Root Mean Square Error (RMSE) of 2.3 cm for COLMAP at 50 lux, improving to 1.9 cm at 100 lux, with OpenMVG and Agisoft Metashape showing comparable accuracy (RMSE 2.1–2.5 cm) but varying processing times. Challenges persist in low-light conditions (RMSE 3.8 cm at 25 lux) and complex geometries, exacerbated by simulated dust (RMSE 2.5 cm), highlighting the need for supplemental lighting and advanced image preprocessing. Point density ranged from 8,500 to 12,300 points/m², with dust and noise reducing detail retention. These findings suggest photogrammetry’s potential as a cost-effective, non-invasive monitoring tool, complementing traditional methods like Light Detection and Ranging (LiDAR). The simulation-based approach provides a scalable framework for optimizing photogrammetric workflows, supporting Industry 4.0 trends in mining safety and efficiency. Future work should validate these results in real-world conditions to address environmental variables like dust and humidity.Podzemna eksploatacija mineralnih sirovina suočava se s izrazitim izazovima u nadzoru stabilnosti podzemnih prostorija i sigurnosti radilišta zbog ograničene vidljivosti i otežanoga pristupa. U ovome radu procjenjuje se izvedivost primjene fotogrametrije za podzemni rudarski monitoring primjenom simulacijskoga okvira, čime se zaobilaze resursno zahtjevna terenska ispitivanja. Sintetski skupovi podataka generirani pomoću softverskih paketa Blender i MATLAB korišteni su za procjenu točnosti, skalabilnosti i ograničenja fotogrametrijskih metoda pod različitim uvjetima osvijetljenosti (25 – 100 luksa), šuma te prisutnosti rudarske prašine. Uspoređena su tri algoritma tipa Structure-from-Motion (SfM) – COLMAP, OpenMVG i Agisoft Metashape – kako bi se ocijenila njihova pouzdanost i učinkovitost. Rezultati pokazuju srednju kvadratnu pogrešku (RMSE) od 2,3 cm za COLMAP pri osvijetljenosti od 50 luksa, s poboljšanjem na 1,9 cm pri 100 luksa. OpenMVG i Agisoft Metashape ostvarili su usporedivu točnost (RMSE 2,1 – 2,5 cm), ali uz različito trajanje obrade podataka. Problemi su zabilježeni pri slaboj osvijetljenosti (RMSE 3,8 cm na 25 luksa) te kod složenih geometrija podzemnih prostorija, pri čemu je prisutnost simulirane rudarske prašine dodatno utjecala na pogrešku (RMSE 2,5 cm). Ti rezultati naglašavaju potrebu za dodatnim jamskim osvjetljenjem te naprednim metodama predobrade snimljenih slika. Gustoća točaka kretala se od 8 500 do 12 300 točaka/m², pri čemu su prašina i šum smanjili razinu detaljnosti modela. Dobiveni rezultati upućuju na velik potencijal fotogrametrije kao troškovno učinkovite i neinvazivne metode za geometrijsko i geomehaničko praćenje stabilnosti podzemnih prostorija, pri čemu ona može nadopuniti konvencionalne tehnike poput LiDAR-a (Light Detection and Ranging). Simulacijski pristup pruža skalabilan okvir za optimizaciju fotogrametrijskih radnih procesa, u skladu s trendovima Industrije 4.0 u pogledu sigurnosti i učinkovitosti podzemne eksploatacije. Buduća istraživanja trebala bi provjeriti rezultate u realnim rudarskim uvjetima uzimajući u obzir varijable poput prašine, vlage i temperaturnih promjena u jamama