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1.
Comparison of continuous local anaesthetic and systemic pain treatment after axillary lymphadenectomy in breast carcinoma patients - a prospective randomized study
Branka Stražišar, Nikola Bešić, 2013, izvirni znanstveni članek

Povzetek: Background. Acute pain after axillary lymphadenectomy is often related mainly to axillary surgery. The aim of the prospective randomized study was to find out if continuous wound infusion of local anaesthetic reduces postoperative pain, consumption of opioids and the incidence of chronic pain compared to the standard intravenous piritramide analgesia after axillary lymphadenectomy in breast carcinoma patients. Methods. Altogether 60 patients were enrolled in the prospective randomized study; half in wound infusion of local anaesthetic and half in the standard (piritramide) group. Results. In the recovery room and on the first day after surgical procedure, the wound infusion of local anaesthetic group reported less acute and chronic pain, a lower consumption of piritramide and metoclopramide, but their alertness after the surgical procedure was higher compared to the standard group. Conclusions. After axillary lymphadenectomy in breast carcinoma patients, wound infusion of local anaesthetic reduces acute pain and enables reduced opioid consumption, resulting in less postoperative sedation and a reduced need for antiemetic drugs. After wound infusion of local anaesthetic there is a statistical trend for reduction of chronic pain.
Ključne besede: breast carcinoma, pain treatment, acute pain
Objavljeno v DiRROS: 22.03.2024; Ogledov: 39; Prenosov: 19
.pdf Celotno besedilo (442,59 KB)

2.
Weathering effects on cellulose acetate microplastics from discarded cigarette butts
Branka Mušič, Andrijana Sever Škapin, 2024, objavljeni znanstveni prispevek na konferenci (vabljeno predavanje)

Povzetek: Cellulose acetate, commonly used in cigarette filters, poses environmental concerns due to its questionable (bio)degradability and prevalent presence in nature. This study compares the weathering effects on two types of cigarette filters: traditional and newer filters used in heated tobacco devices (HTP). Microplastics were derived from used cigarette parts and then subjected to artificial aging. Analytical techniques (Thermogravimetry-Differential Scanning Calorimetry TG/DSC, Fourier-Transform Infrared Spectroscopic Analysis (FTIR)) and loose bulk density measurements were employed pre- and post-aging cellulose acetate of both types of samples. Despite increasing evidence influencing European Union (EU) directives on tobacco product disposal, there's a lack of systematic analysis on the weathering impact, especially concerning the touted environmental benefits of newer filters. Results indicate decreased particle size in cellulose acetate filters post-aging. Variances were observed in thermal behavior, yet FTIR spectra remained unchanged.
Ključne besede: cellulose acetate, cigarette filters, microplastics, artificial weathering, polymer degradation
Objavljeno v DiRROS: 12.03.2024; Ogledov: 84; Prenosov: 79
.pdf Celotno besedilo (84,58 MB)
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3.
Green transition in slovenian building and civil engineering industry : 10 years of research on alkali-activated materials and alkali-activated foams
Barbara Horvat, Branka Mušič, 2024, objavljeni znanstveni prispevek na konferenci (vabljeno predavanje)

Povzetek: The building and civil engineering industry yearly causes more than 40% of man-made CO2 and consumes raw materials for two-thirds of Mont Everest. To decrease the carbon footprint and consumption of raw materials, alkali-activated materials (AAMs) are researched as an alternative to conventional building and civil engineering products like cements, mortar, and ceramics. Ideally, locally available waste materials are used as ingredients: (i) as precursors that react with alkali and form an aluminosilicate network, and (ii) as fillers that get permanently encapsulated and safely stored in AAMs. The addition of gas bubbles and lightweight fillers transforms AAMs into alkali-activated foams and alkali-activated lightweight materials that have the potential to be used as thermal and acoustic insulation materials. Although AAMs are researched worldwide, this review focuses on the state-of-the-art localised solely to Slovenia, particularly on the materials and curing procedures used, as well as on the scientific contribution of the basic research. Besides, the year 2024 marks 10 years of research on alkali activation of raw and waste inorganic materials in Slovenia.
Ključne besede: secondary raw material, alkali-activated material, alkali-activated foams, alkali, circular economy, microwave irradiation, mechanical strength
Objavljeno v DiRROS: 12.03.2024; Ogledov: 71; Prenosov: 64
.pdf Celotno besedilo (84,58 MB)
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4.
Influence of ammonium polyphosphates and 2,4,6-triamino-1,3,5-triazine on the mechanical-physical properties of polyurethane and alkali-activated materials
Branka Mušič, Barbara Horvat, 2024, objavljeni znanstveni prispevek na konferenci

Povzetek: In building constructions, the tendency towards an ever-better material directs us to composite materials. In this work, we prepared an organic-organic and organic-inorganic composite material by incorporating fire retardants, ammonium polyphosphates, and 2,4,6-triamino-1,3,5-triazine, into a polyurethane network and an aluminosilicate network (ASN) of alkali-activated material. Polyurethane foams (PUR) are well-known materials that, due to their properties, such as low weight-to-strength ratio, low electrical and thermal conductivity, flexibility, and relatively simple preparation process, are used in various industries, also in the construction industry, e.g., for thermal insulation of windows and doors or fixing and sealing joinery. Opposite, the ASN of alkali-activated metakaolin, successfully paves the way for new applications, such as high-temperature protection. In this paper, these interactive properties of prepared composites are studied using thermal testing and mechanical analysis. It was found that inhibitors significantly increase the fire resistance of PUR systems while they slightly reduce the mechanical properties. Incorporating polymer flame retardant into ASN in building products, such as façade panels , can decrease the mechanical properties but can offer the non-flammable building envelope not get heated from burning surroundings, i.e., not becoming a convection heat source, but rather represent a fire-distinguisher for flammable materials.
Ključne besede: flame retardants, polyurethane, alkali activated material, metakaolin, microwave irradiation, mechanical strength
Objavljeno v DiRROS: 12.03.2024; Ogledov: 67; Prenosov: 31
.pdf Celotno besedilo (2,52 MB)
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5.
Waste rubber incorporated in the alkali-activated metakaolin’s aluminosilicate network enhanced by microwave irradiation
Barbara Horvat, Branka Mušič, 2024, objavljeni znanstveni prispevek na konferenci

Povzetek: Building materials represent the possibility of prolonging the life of waste materials. The key is to ensure that the products are suitable for their function. So we activated metakaolin with the alkaline Na-silicate solution in the ratio that ensures the prevention of efflorescence and high mechanical strength (Horvat and Ducman, 2019). As the waste material (to be incorporated in the aluminosilicate network (ASN) of the alkali-activated metakaolin) ground waste rubber from electric cables was used in the preselected mass ratios. Its inclusion in products, like paving stones, can reduce stiffness, improve durability, dampen vibrations, and reduce road noise. The mechanical strengths of test samples with rubber present on the active surface or slightly below were higher compared to samples where rubber was encapsulated throughout the volume. Compressive strength was higher when samples were irradiated with low powers of microwaves while irradiation with higher powers led to the foaming of alkali-activated slurry. The encapsulation quality of the ground rubber was evaluated by SEM while the chemical influence on ASN was determined by EDS, FTIR, and XRD. Slipperiness change on the active surface of pavement stones proved that the addition of the ground rubber enhanced the walking safety of the product.
Ključne besede: secondary raw material, alkali activated material, waste rubber, metakaolin, encapsulation of organic in inorganic material, microwave irradiation, mechanical strength
Objavljeno v DiRROS: 12.03.2024; Ogledov: 60; Prenosov: 31
.pdf Celotno besedilo (13,99 MB)
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6.
Thermal insulation and flammability of composite waste polyurethane foam encapsulated in geopolymer for sustainable building envelope
Barbara Horvat, Nataša Knez, Uroš Hribar, Jakob Koenig, Branka Mušič, 2024, izvirni znanstveni članek

Povzetek: Polyurethane foam (PUR) is a lightweight, thermally insulating, widely used, and highly flammable material that has after its use an adverse effect on the environment, i.e., PUR disposal is considered hazardous. Its flammability can be mitigated using various fire retardants, but they do not change the hazardous nature of waste PUR. Therefore, in the current study, waste PUR with and without flame retardants based on N and P was incorporated into a geopolymer, the alkali-activated material (AAM) based solely on metakaolin, to evaluate the potential recycling route of waste PUR while taking into account its flammability, so it can enter safely into the circular economy through the building industry. To enhance the mechanical properties of the composite, a fresh mixture was irradiated with microwaves. However, the irradiation of geopolymer containing PUR negatively influenced mechanical performance, which led to the evaluation of the behaviour of the complex dielectric constant of PUR and fire retardants. Materials and composites were evaluated regarding their chemistry, mineralogy, microstructure, and porosity to connect the structure with extrinsic properties like geometrical density, thermal conductivity, and fire properties. Nonetheless, positive influences of PUR being encapsulated in the geopolymer were lowered density (from 1.8 to 1.6 kg/l) and improved thermal insulation ability (from 940 to 860 mW/(m·K)) of the composites: with the inclusion of <5 % of PUR, thermal insulation improved by nearly 10 %. However, the contribution of PUR to the composite originated from its skeleton, which has more than 15 times bigger geometrical density (0.81 kg/l) compared to the density of the skeleton (0.047 kg/l). This offers an open field for further advancements of thermal properties, but would also lead to a decrease of the compressive strength, which was already lowered from 90 MPa for 30 % with <5 % of added grated PUR. Furthermore, the flammable nature of PUR and its other drawbacks can be controlled by permanent embedding in the noncombustible structure of geopolymer, making the envelope of sustainable buildings green and safer. Overall, including grated waste PUR in geopolymer represents a promising, easy, cost-effective recycling path with low energy consumption, where the composite cannot develop fire on a scale of pure PUR, even in the worst-case scenario, but only if the composite is designed in a way, that flammable materials cannot join flames during their combustion. This paper gives prospects to other flammable waste materials to be safely used in the circular economy, and to porous materials to shape properties of the composite by their intrinsic and/or extrinsic properties.
Ključne besede: waste polyurethane foam, polymeric flame retardants, alkali activated material, metakaolin, microwave irradiation, thermal-fire behaviour, mechanical strength
Objavljeno v DiRROS: 01.03.2024; Ogledov: 141; Prenosov: 118
.pdf Celotno besedilo (29,74 MB)
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7.
8.
Uporaba deksmedetomidina za paliativno sedacijo : prikaz primera
Iztok Potočnik, Branka Stražišar, 2023, strokovni članek

Povzetek: Paliativna oskrba ob koncu življenja, v katerem se pojavijo znaki pričetka umiranja s pešanjem vitalnih organov in se končajo s smrtjo, je pomemben del celostne paliativne oskrbe. Včasih, ob izredno težkih refraktarnih simptomih napredovale bolezni, je lahko primerna tudi paliativna sedacija. Paliativna sedacija je medicinski postopek, kjer je potrebno strogo upoštevati protokol izvedbe, in slediti etično moralnim vidikom in nikakor prekoračiti črte evtanazije. Paliativno sedacijo je potrebno skrbno načrtovati, se pogovoriti z bolnikom, svojci in s celotnim timom, ki bolnika oskrbuje (zdravniki in negovalno osebje), ga ustrezno dokumentirati in nadzorovati. Pomemben je multidisciplinarni pristop, ko vsak od vključenih zdravnikov specialistov in negovalnega osebja osvetli svoj vidik. V prispevku smo opisali klinični primer bolnice, ki se je zaradi refraktarnega simptoma sprva odločila za paliativno sedacijo, kasneje pa je svojo odločitev spremenila. Pri opisanem primeru s standardnimi učinkovinami sprva nismo uspeli doseči ustrezne globine paliativne sedacije, zato smo se odločili uporabiti deksmedetomidin. Z deksmedetomidinom smo dosegli plitvo sedacijo, ki je bolnici olajšala trpljenje do te mere, da se je tudi odločila za prekinitev paliativne sedacije. Deksmedetomidin je učinkovita in varna učinkovina, ki si išče svoje mesto tudi v paliativni medicini. V literaturi so objavljeni samo posamezni prikazi kliničnih primerov in pregledov področja, ni pa še objavljene randomizirane raziskave. V prihodnosti se taka raziskava načrtuje
Ključne besede: umirajoči bolniki, pozna paliativna oskrba, paliativna sedacija, multidisciplinarni pristop
Objavljeno v DiRROS: 26.02.2024; Ogledov: 103; Prenosov: 33
.pdf Celotno besedilo (85,65 KB)

9.
PUR in geopolymer
Barbara Horvat, Nataša Knez, Uroš Hribar, Jakob Koenig, Branka Mušič, 2024, zaključena znanstvena zbirka raziskovalnih podatkov

Povzetek: The dataset supports the results shown in the tables and figures in the article entitled “Thermal insulation and flammability of composite waste polyurethane foam encapsulated in geopolymer for sustainable building envelope” (doi: 10.1016/j.jclepro.2024.141387). It contains measurements of fire-behaviour characteristics, thermal conductivity, the behaviour of the material in the electromagnetic field in relation to the frequency, mechanical and structural evaluation, as well as chemical and mineralogical analysis.
Ključne besede: measurements, waste polyurethane foam, polymeric flame retardants, alkali activated material, metakaolin, microwave irradiation, thermal-fire behaviour, mechanical strength
Objavljeno v DiRROS: 20.02.2024; Ogledov: 183; Prenosov: 156
.xlsx Raziskovalni podatki (2,51 MB)
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10.
Cysteine proteinase inhibitors stefin A and stefin B in operable carcinoma of the head and neck : Inhibitorji cisteinskih proteinaz stefin A in stefin B pri operabilnem karcinomu glave in vratu
Primož Strojan, Marjan Budihna, Alojz Šmid, Branka Svetic, Ivan Vrhovec, Janko Kos, Janez Škrk, 2002, izvirni znanstveni članek

Povzetek: Purpose. To evaluate the significance of cysteine proteinase inhibitors stefins (Stefs) A and B for a treatment decision and prognosis in operable squamous cell carcinoma of the head and neck (SCCHN). Patients and methods. Stefs A and B concentrations were determined immunobiochemically using ELISAs in cytosols prepared from the tumor and adjacent normal mucosa from 91 patients with operable SCCHN. The median follow-up period of patients alive atthe close-out date was 5.8 years (range, 5-9.3 years). Results. Stef A concentrations were significantly higher in tumor compared to normal mucosa (FM.05). When a subgroup with clinically palpable nodes) at presentation was taken into consideration (n=57), a significant difference in Stef A (P=0.03) and Stef B (P=0.02) concentrations between those with negative and positive necks, as determined on histopathological examination, was observed. On the univariate survival analysis, higher Stefsć concentrations turned to be prognostically advantageous. Stef A proved its independent prognostic significance also on multivariate setting. Conclusions. With the capability todifferentiate between the pN0- and pN+-stages of the disease in the patientsoriginally presented as node-positive, Stefs A and B could be useful markers when deciding on the extent of neck surgery. In addition, both Stefs proved to be reliable prognosticators for survival in patients with operable SCCHN.
Objavljeno v DiRROS: 31.01.2024; Ogledov: 118; Prenosov: 29
.pdf Celotno besedilo (114,91 KB)

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