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Laser-induced cavitation bubble interaction with surface-attached bubbles
No full textWe study the interaction of laser-induced cavitation bubbles generated atop an electrode covered with hydrogen bubbles. The bubbles respond to the shock wave from laser-induced breakdown and the flow field of expanding and collapsing cavitation bubbles. High-speed imaging reveals that both the shock wave and subsequent flow contribute to bubble detachment and electrode clearance. Clearance occurs within an approximately circular area exceeding 3 times the maximum bubble radius, with partial clearance extending to 5 times this radius, which is considerably larger than reported for particulate or liquid contaminant removal. The initial shock wave propagates as a void fraction wave upon reaching the bubbles, producing radially propagating bubble disturbance with velocities ranging from 490 m/s at low bubble concentrations to 50 m/s at high concentrations. These speeds are within the range expected for linear waves in bubbly liquids according to Wood’s formula. Bubble removal persists for 10 ms, approximately 100 times longer than the cavitation bubble lifetime, which is attributed to long-lasting vortical flow generated by non-spherical cavitation bubble collapse. The findings may help to improve the removal of particulate contaminants as well as reducing ohmic loads in electrolyzers
Veterinary perspectives on biosecurity measures in small-scale farming systems across European countries
No full textMaintaining sufficient levels of biosecurity at the farm level is crucial to prevent the introduction and spread of pathogens. However, data on biosecurity awareness and implementation in small-scale or backyard (hereafter referred to as small-scale) holdings across Europe are lacking. While the risk posed by these farms is generally regarded as limited, they represent a diverse group of farmers and do play a role in disease introduction and spread. The aim of this study was to explore veterinarians\u27 perspectives on small-scale farming in Europe, including the frequency of farm visits, the definition of small-scale farming, the current status of biosecurity, and the most important measures to prevent pathogen introduction and spread. A multidisciplinary team developed a comprehensive survey to collect veterinarians\u27 perspectives on biosecurity in small-scale farms. The survey was translated into 16 languages, digitalised, and distributed online between July and December 2024 by participants of COST Action BETTER. Data were analysed descriptively, and clusters of veterinarians were distinguished using multiple correspondence analysis. In total, 346 veterinarians from 23 countries participated in the survey. There is no standard definition of small-scale farming throughout Europe. According to the participating veterinarians, a small-scale farm was defined as having a median number of fewer than 20 cattle, 30 small ruminants, 13 pigs, or 99 heads of poultry. Three clusters of veterinarians were identified based on geographical location, field experience, biosecurity training, and perceived biosecurity awareness within the small-scale farming community. Biosecurity measures already applied in small-scale farming included fencing, carcass management, and biosecurity measures related to purchasing and feeding practices. According to the participating veterinarians, the most important biosecurity measures for small-scale farms to prevent pathogen introduction and spread included factors related to the introduction of animals, such as quarantine facilities, testing for health status, and purchasing animals from farms with a high health status. Besides factors related to the introduction of animals, hygiene measures and fencing were also frequently indicated as the most important biosecurity measures. Nevertheless, significant differences were found between the clusters regarding the importance of specific biosecurity measures. This study provides valuable insights into the perceived awareness, implementation, and desired biosecurity measures in European small-scale farming and underscores the importance of integrating small farms into “One Health” strategies, given their potential role in the spread of infectious diseases
Tricyclic boronic acids as broad-spectrum serine and metallo-β-lactamase inhibitors with in vitro activity against acinetobacter baumannii
No full textIntroduction With β-lactams remaining the most widely prescribed antibacterials worldwide, their continuing clinical efficacy remains an important therapeutic goal. Rapid spread of serine and metallo-ß-lactamases (SBLs and MBLs, respectively), which can inactivate β-lactams, is increasingly threatening this objective. Finding clinically useful inhibitors of MBLs, for which no FDA approved treatment currently exists, is of interest. Areas covered This article concisely reviews structurally novel xeruborbactam-inspired tricyclic boronates (reported in US 2025/0223303) with promising inhibitory activities in vitro. The literature search was conducted using SciFinder and Patentscope. By introducing novel thioether-based C5 sidechains onto the previously optimized bicyclic boronate core, the inventors explored novel chemical space yielding SBL/MBL inhibitors with seemingly improved activities against carbapenem-resistant (CR) Escherichia coli, Klebsiella pneumoniae, and, importantly, Acinetobacter baumannii, when used in combination with meropenem and/or biapenem (at least with respect to taniborbactam, i.e. boronate inhibitor in late-stage clinical development). Expert opinion Due to the major societal importance of β-lactams for modern medicine, and the clearly demonstrated clinical potential of functionalized cyclic boronates as potent dual-acting SBL/MBL inhibitors when used in combination therapies, there is ample opportunity and scope for continued investigation of this pharmacophore, particularly in the context of discovering new therapeutic options for CR infections
Multivariate time series and cointegration
No full textAnaliza časovnih vrst zaradi svoje velike uporabnosti velja za eno izmed pomembnejših področij statistike. Magistrsko delo zajema predstavitev multivariatnih časovnih vrst in vektorskih modelov časovnih vrst, s katerimi jih lahko opišemo. Natančneje obravnavamo vektorske avtoregresijske modele drsečih sredin, metode njihove identifikacije in napovedovanje prihodnjih vrednosti. Posvetimo se tudi predstavitvi koncepta kointegracije. Pri tem obravnavamo vektorski model korekcij napak, različne metode testiranja in načine ocenjevanja kointegracijskih vektorjev. Lotimo se tudi empiričnega modeliranja multivariatnih časovnih vrst v programskem jeziku R. Med seboj primerjamo napovedi modelov z upoštevanjem in brez upoštevanja prisotne kointegracije.Due to its great usefulness, time series analysis is regarded as one of the most important fields in statistics. This Master\u27s thesis focuses on multivariate time series and the vector time series models they follow. A more detailed examination of vector autoregressive moving average models is provided, including methods for their identification and use in forecasting. Furthermore, the concept of cointegration is introduced. In this context, the vector error correction model is presented, along with various testing procedures and approaches to estimating cointegrating vectors. The thesis also includes empirical modeling of multivariate time series using the R programming language. Finally, a comparative analysis of forecasts from a model that accounts for cointegration and a model that does not is conducted
The impact of spatial obstacles and the number of occupants on evacuation time in case of accidents in a healthcare facility
No full textMagistrsko delo obravnava vpliv prostorskih ovir in števila prisotnih gibalno neoviranih oseb različnih starostnih skupin na evakuacijski čas v primeru nezgod v zdravstvenem domu. Zdravstvene ustanove predstavljajo specifično okolje z vidika evakuacije, saj združujejo visoko gostoto uporabnikov, raznolike starostne skupine ter prisotnost oseb z omejeno mobilnostjo, hkrati pa vsebujejo številne prostorske ovire v obliki pohištva in medicinske opreme. Namen magistrske naloge je bil analizirati, kako omenjeni dejavniki vplivajo na učinkovitost evakuacije in prepoznati kritične razmere, ki lahko bistveno podaljšajo evakuacijski čas.
Analiza temelji na računalniških simulacijah evakuacije, izvedenih s programom Pathfinder, pri čemer je bil natančen tloris zdravstvenega doma pripravljen v programskem okolju AutoCAD. Obravnavanih je bilo devet evakuacijskih scenarijev, ki so se razlikovali glede na število oseb ter glede na število in razporeditev prostorskih ovir. Poseben poudarek je bil namenjen primerjavi scenarijev brez ovir, scenarijev z ovirami zunaj izhodnega območja ter scenarijev z ovirami, nameščenimi neposredno pred evakuacijskim izhodom.
Rezultati so pokazali, da se evakuacijski čas z naraščanjem števila oseb povečuje, pri čemer razmerje ni linearno. Največji vpliv na podaljšanje evakuacijskega časa ima postavitev ovir v neposredni bližini evakuacijskih izhodov, medtem ko samo število ovir brez posega v izhodno območje nima odločilnega vpliva. Ugotovitve potrjujejo pomen prostorske razporeditve in nadzora nad zasedenostjo objekta ter poudarjajo uporabnost računalniških simulacij kot podpornega orodja pri načrtovanju varne evakuacije v zdravstvenih ustanovah.The master\u27s thesis examines the impact of spatial barriers and the number of able-bodied persons of different age groups present on evacuation time in the event of accidents in a health center. Healthcare buildings represent a particularly challenging evacuation environment due to high occupancy levels, diverse user profiles, the presence of mobility-impaired persons, and numerous spatial obstacles such as furniture and medical equipment. The primary objective of this study was to analyse how these factors influence evacuation efficiency and to identify critical conditions that may significantly prolong evacuation time.
The analysis is based on computer evacuation simulations performed using the Pathfinder software, while a detailed floor plan of the healthcare facility was developed in AutoCAD. A total of nine evacuation scenarios were analysed, differing in the number of occupants and in the number and spatial arrangement of obstacles. Special emphasis was placed on comparing scenarios without obstacles, scenarios with obstacles located outside exit zones, and scenarios with obstacles positioned directly in front of evacuation exits.
The results indicate that evacuation time increases with the number of occupants, and that this relationship is non-linear. The most significant factor affecting evacuation time is the placement of obstacles directly in front of evacuation exits, whereas the mere number of obstacles outside critical exit areas has a comparatively minor effect. The findings highlight the importance of proper spatial organisation, unobstructed exits, and occupancy control. Furthermore, the study confirms that computer-based evacuation simulations represent a valuable tool for supporting evacuation planning and improving safety in healthcare facilities
Detection of malware mechanisms of action
No full textMagistrsko delo podaja teoretični pregled zlonamerne programske opreme ter izdelavo lastnega vzorca in testiranje detekcije mehanizmov zlonamerne programske
opreme.
Izpostavljene so najznamenitejše vrste zlonamerne programske opreme, vključno z izsiljevalsko, vohunsko in brezdatotečno programsko opremo, trojanskimi konji, črvi, virusi, omrežji avtomatskih robotov, logičnimi bombami in hibridi, skupaj z njihovimi najbolj znanimi predstavniki. Obravnavani so tudi tipični mehanizmi zlonamerne programske opreme, kot so poviševanje privilegijev, kraja in spreminjanje podatkov, vztrajnost, oddaljen nadzor, izogibanje detekciji ter destruktivna dejanja. Analizirane so različne metode detekcije zlonamerne programske opreme: zaznavanje na podlagi podpisov, statična in dinamična analiza ter sistemi za zaznavanje in odziv končnih točk (angl. Endpoint Detection and Response – EDR) in razširjeno zaznavanje in odziv (angl. Extended Detection and Response – XDR).
V praktičnem delu je implementiran prototipni vzorec zlonamerne programske opreme, ki vsebuje naslednje mehanizme: šifriranje datotek, vzpostavitev t. i. povezave povratne lupine (angl. reverse shell), spreminjanje registra, samoreplikacijo in izvajanje z zakasnitvijo. Ta vzorec je testiran v izoliranem laboratorijskem okolju na različnih brezplačnih in plačljivih varnostnih orodjih – testirana je stopnja uspešnosti njihove detekcije.
Rezultati so presenetljivi in zaskrbljujoči, saj niti brezplačne niti plačljive različice antivirusnih programov oziroma EDR/XDR-sistemov niso bile uspešne pri zaznavanju relativno preprostega novega vzorca zlonamerne programske opreme. Skoraj vsaka preizkušena rešitev je bila uspešna le pri detekciji posameznih mehanizmov, nobena pa ni dosegla 100-odstotne uspešnosti. To jasno kaže, da se za prvo detekcijo nove zlonamerne programske opreme ne moremo z zagotovilom zanašati na tovrstne programe ter da datotek ali aplikacij, ki niso preverjene oziroma za katere sumimo, da bi lahko bile škodljive, ne bi smeli odpirati ali zaganjati. Če to ni mogoče, jih je treba dodatno preveriti oziroma testirati v varnem okolju.The master’s thesis provides a theoretical overview of malicious software (malware), along with the development of a custom malware sample and the evaluation of detection capabilities for malware mechanisms.
It highlights the most prominent types of malicious software, including ransomware, spyware, fileless malware, trojans, worms, viruses, botnets, logic bombs, and hybrid forms, as well as their most well-known representatives. The thesis also examines common malware mechanisms, such as privilege escalation, data theft and manipulation, persistence, remote control, evasion of detection, and destructive actions. Furthermore, various malware detection methods are analysed, including signature-based detection, static and dynamic analysis, and EDR (Endpoint Detection and Response)/XDR (Extended Detection and Response) systems.
In the practical section, a prototype malware sample was implemented, containing the following mechanisms: file encryption, establishment of a reverse-shell connection, registry modification, self-replication, and delayed execution. This sample was tested in an isolated laboratory environment using various free and commercial (professional/industrial) security tools, and the effectiveness of their detection was evaluated.
The results were both surprising and concerning, as neither free nor commercial antivirus solutions nor EDR/XDR systems were successful in detecting a relatively simple zero-day malware sample. Most of the tested solutions were able to detect individual mechanisms, yet none achieved 100% accuracy. This clearly demonstrates that such tools cannot be fully relied upon for the initial detection of new malware, and that files or applications that are unverified or suspected to be malicious should not be opened or executed. If opening/running such files cannot be avoided, they must be additionally examined or tested within a secure environment
Genetic diversity of Campylobacter concisus isolates from Slovenian patients with iInfectious diarrhoea
No full textCampylobacter concisus is recognized as a potential pathogen in gastrointestinal diseases, particularly in patients with chronic intestinal diseases. This study investigates the genomic characteristics, phylogenetic distribution, virulence factors, resistance genes and presence of plasmids in C. concisus isolates from Slovenian patients with community-acquired infectious diarrhoea. Prospectively collected isolates were analysed using whole-genome sequencing (WGS). WGS analysis revealed substantial genetic diversity among isolates, with distinct differences observed between two genomospecies (GS1, GS2). GS1 isolates had smaller genomes, lower GC content, and fewer coding regions than GS2 isolates. Multilocus sequence typing confirmed a high degree of genetic diversity, with most isolates belonging to novel sequence types. Plasmids, including pSma1 and pICON, were more prevalent in GS2 isolates. The virulence factors Zot and Exo9 toxins were detected in both genomospecies, with Zot predominantly found in GS1 and Exo9 in GS2. The T6 secretion system was prevalent in both groups, whereas the T4SS was less frequently observed. The combination of the T6SS, plasmids, and toxins suggests a complex mechanism of pathogenicity. This study highlights the high genetic diversity of C. concisus and provides new insights into its genomic features and virulence factors. The presence of plasmids and secretion systems, particularly the T6SS, underscores the potential of C. concisus for adaptation and pathogenicity
Software updates under resource constraints
No full textInternet stvari (IoT) predstavlja eno najhitreje rastočih področij sodobne
informatike, kjer naprave delujejo z izrazito omejenimi procesorskimi, po-
mnilniškimi in energetskimi viri. Zaradi teh omejitev je varno posodabljanje
programske opreme zahtevna naloga, saj mora zagotoviti zanesljiv prenos,
preverjanje integritete in čim manjšo porabo energije. Obstoječe rešitve po-
gosto ne omogočajo celovitega preverjanja, ali je bila posodobitev uspešno
nameščena in ali naprava po njej deluje pravilno.
Magistrsko delo obravnava razvoj razširjene implementacije standarda
IETF SUIT, ki združuje energetsko učinkovitost, varnost in interoperabil-
nost. Predlagana rešitev temelji na dvoslojni arhitekturi, ki vključuje strežni-
ško komponento in komponento na napravi, ter uvaja mehanizme za odda-
ljeno preverjanje namestitev. Z uporabo kompaktnega formata CBOR in
kriptografskih mehanizmov COSE delo raziskuje ravnovesje med zanesljivo-
stjo, varnostjo in porabo energije ter prispeva k razvoju univerzalnega in s
standardom skladnega sistema za varne posodobitve IoT-naprav.The Internet of Things (IoT) represents one of the fastest-growing areas
of modern computer science, where devices operate under strict constraints in
processing power, memory, and energy availability. These limitations make
secure firmware updates particularly challenging, as they must ensure reli-
able data transfer, integrity verification, and minimal energy consumption.
Existing solutions often fail to provide comprehensive confirmation that an
update has been successfully installed and that the device continues to op-
erate correctly afterwards.
This master’s thesis presents the development of an extended implemen-
tation of the IETF SUIT standard, combining energy efficiency, security, and
interoperability. The proposed solution is based on a two-layer architecture
consisting of a server component and a device-side component, and introduces
mechanisms for remote installation verification. By employing the compact
CBOR format and COSE cryptographic mechanisms, the thesis explores the
balance between reliability, security, and energy consumption, contributing
to the development of a universal and standards-compliant system for secure
firmware updates on IoT devices
Prepoznavanje različnih čustev skozi branje otroške in mladinske književnosti
No full textV prispevku je predstavljen razvoj otrok in mladostnikov s psihološkega, etičnega in literarnega vidika, saj so čustva izrazito interdisciplinarna tematika. V sodobni otroški in mladinski književnosti se pojavljajo različna čustva ali kombinacija več čustev, najpogosteje nasprotnih (npr. veselje – žalost, ljubezen – sovraštvo, strah – pogum). Predstavljeni so primeri literarnih del, v katerih so čustva pomembna tema, dela pa so kakovostna in sodijo v različne literarne vrste.This article presents the development of children and young adults from a psychological, ethical, and literary aspect because emotions are a distinctively interdisciplinary topic. Different emotions or combinations of multiple emotions, often opposing (e.g., joy and sadness, love and hate, or fear and courage), appear in contemporary children’s and young adult literature. Examples of highquality literary works are presented, in which emotions are an important theme and which belong to a variety of genres
Emocije i slovenska književnost u nastavi hrvatskoga jezika: na primjeru romana Šavrinke Marjana Tomšiča
No full textPrispevek analizira čustvene elemente v romanu Šavrinke Marjana Tomšiča s filološkega in pedagoškega vidika. Zgodba romana, postavljena v Istro ob koncu 19. stoletja, osvetljuje življenje žensk, ki so prehajale mejo med slovenskim zaledjem in Trstom. Avtor skozi uporabo narečnega jezika, simbolike prostora in pripovednih glasov ustvarja izrazit čustveni svet glavne junakinje. Prispevek vključuje tudi metodični model za delo z romanom v srednji šoli