1981. Improving the surface properties of additive-manufactured Inconel 625 by plasma nitridingDanijela Anica Skobir Balantič, Črtomir Donik, Bojan Podgornik, Aleksandra Kocijan, Matjaž Godec, 2023, izvirni znanstveni članek Povzetek: As a surface-hardening technique, plasma nitriding is a common procedure for improving the properties of
conventional Ni-based alloys. The diffusion of nitrogen hardens a layer on the surface of the alloy, leading to
better wear resistance and a higher coefficient of friction, as well as a higher surface hardness. This study reports
the effect of plasma nitriding on additive-manufactured (AM) Inconel 625 (IN625) compared to its conventional
manufactured and nitrided counterparts. The samples produced with the laser powder-bed fusion (LPBF) process
were subsequently plasma nitrided in the as-built condition, stress-relief annealed at 870 °C and solution treated
at 1050 °C. The plasma nitridings were carried out at 430 °C and 500 °C for 15 h. The growth kinetics of the
nitride layer of the AM samples depends on the prior heat treatments and is faster in the as-built state due to the
specific cellular structure. The lower nitriding temperature leads to the formation of expanded austenite in the
nitride layer, while at the higher nitriding temperature, the expanded austenite decomposes and CrN precipitation
occurs. The XRD and SEM analyses confirmed the presence of two layers: the surface layer and the
diffusion layer beneath. The lower nitriding temperature caused the formation of expanded austenite or a
combination of expanded austenite and CrN. The higher nitriding temperature led to the decomposition of the
expanded austenite and to the formation/precipitation of CrN. The higher nitriding temperature also decreased
the corrosion resistance slightly due to the increased number of precipitated Cr-nitrides. On the other hand, the
wear resistance was significantly improved after plasma nitriding and was much less influenced by the nitriding
temperature. Ključne besede: additive manufacturing, powder-bed fusion, plasma nitriding, expanded austenite, wear and corrosion resistance, Ni-based alloy Objavljeno v DiRROS: 31.01.2024; Ogledov: 388; Prenosov: 146 Celotno besedilo (7,98 MB) Gradivo ima več datotek! Več... |
1982. A brief overview of the tumor vaccines through the last decadeSrdjan Novaković, Barbara Jezeršek Novaković, 2002, pregledni znanstveni članek Povzetek: How to destroy cancer cells without damaging the normal cells? How to make conventional methods of systemic cancer treatment that predominantly comprise cytotoxic drugs more selective and prevent the development of drug resistance?There is an abundance of such guestions that do not have simple answers. If, a few years ago, unselective cytotoxic drugs were the method of choice for the treatment of cancer, in the last 25 years we are witnessing therapid transition of immunotherapy from the laboratories to the clinics. Among the most attractive and promising immunotherapies for cancer, a special place is reserved for tumor vaccines. Exploiting the latest knowledge in immunology, tumor physiology, as well as in molecular biology, many outstanding approaches for the creation of tumor vaccines have been developed.With no intention to be comprehensive, in the present article some of those approaches are reviewed. Objavljeno v DiRROS: 31.01.2024; Ogledov: 327; Prenosov: 68 Celotno besedilo (97,46 KB) |
1983. Infantile myofibromathosis of the maxilla. A case reportNataša Ihan Hren, 2002, strokovni članek Povzetek: Background. Infantile myofibromatosis is a rare benign tumour in children. Itscharacteristic symptoms are firm masses in soft tissues, bones and visceralorgans, and its common locations are head and neck. Three forms are well known: solitary, multicentric and visceral myofibromatosis. All have excellent prognosis, except the last one that may be lethal. Spontaneous regression can occur. Case report. We present an unusual case of infantile myofibromatosis of the maxilla in an adolescent. Conclusions. The infantile myofibromatosis should be managed with special caution because of the differential-diagnostic similarity with fibrosarcoma, leomyosarcoma, and histiocytosis. Objavljeno v DiRROS: 31.01.2024; Ogledov: 272; Prenosov: 68 Celotno besedilo (145,86 KB) |
1984. |
1985. LymphangioleiomyomatosisFranc Anderluh, 2002, pregledni znanstveni članek Povzetek: Background. Lymphangioleiomyomatosis is a rare disease of unknown origin, which affects women in their reproductive period. It is characterised by non-neoplastic proliferation of atypical smooth muscle cells in the lung parenchyma, lymphatic vessels and mediastinal and abdominal lymph nodes. The most common presenting symptoms are spontaneous pneumothorax, dyspnea, hemoptysis and chylothorax. Conclusions. High-resolution computed tomography (HRCT) and open lung biopsy followed by the immunohistologic studies are two diagnostic procedures with which diagnosis can be confirmed. Various treatmentmodalities are applied, particularly hormonal therapy, though their efficacy remain unknown. The prognosis of patients is bad. Objavljeno v DiRROS: 31.01.2024; Ogledov: 277; Prenosov: 47 Celotno besedilo (76,06 KB) |
1986. Carotid angioplasty with cerebral protectionZoran Miloševič, Bojana Žvan, Marjan Zaletel, Miloš Šurlan, 2002, izvirni znanstveni članek Povzetek: Background. Carotid endarterectomy (CF.A) is widely used in the management of high-rade carotid stenosis: It is a surgical procedure requiring general anaesthesia and is suitable only for lesions located at or close to the carotid bifurcation. It may develop complications, such as stroke, death, cranial nerve palsies, wound haematoma and cardiac complications. The risk of complications is increased in patients with recurrent carotid artery stenosis following CEA, in subjects undergoing radiotherapy to the neck, and in patients with cardiopulmonary disease. The drawbacks of CEA have led physicians to search for alternative treatment options. Carotid angioplasty and stenting (CAS) is less invasive than CEA. The method is particularly suitable for the treatment of recurrent stenosis after previous CEA and distalinternal artery stenosis, which is inaccessible for CEA. CAS does not cause cranial nerve palsies. Moreover, it does not require general anaesthesiaand causes lower morbidity and mortality in patients with severe cardiopulmonary disease. The complications of CAS include stroke due to distalimmobilisation of a plaque or thrombus dislodged during the procedure, abrupt vessel occlusion due to thrombosis, dissection or vasospasm, and restenosis due to intmal hyperplasia. CAS is a relatively new procedure; therefore, it is essential to establish its efficacy and safety before it is introduced widely into clinical practice. Patients and methods. In Slovenia, we have also started with carotid angioplasty by the study: Slovenian Carotid Angioplasty Study (SCAS). We performed CAS in 17 patients (12 males and 5 females) aged from 69 to 82 years. All patients were symptomatic with stenosisgreater than 70 %. 10 patients suffered transient ischemic attacks, 4 patients minor strokes and 3 patients amaurosis fugax. (Abstract truncated at 2000 characters) Objavljeno v DiRROS: 31.01.2024; Ogledov: 305; Prenosov: 76 Celotno besedilo (116,39 KB) |
1987. Metodologija za oceno stanja lesnopredelovalnega sektorja : tržni potenciali okroglega lesa v Sloveniji in njegova nadaljnja uporabaŠpela Ščap, Janez Zafran, Nike Krajnc, 2022, elaborat, predštudija, študija Ključne besede: gozdno-lesni sektor, gozdni lesni sortimenti, okrogli les, lesnopredelovalna panoga, zaloga ogljika v lesnih izdelkih Objavljeno v DiRROS: 31.01.2024; Ogledov: 317; Prenosov: 0 |
1988. Primary non-Hodgkin lymphoma of the cecum: a case reportMateja Kropivnik, Breda Jamar, Bojana Černelč, 2002, strokovni članek Povzetek: Background. Primary lymphoma of the colon is rare, constituting 0.4 % of primary colonic malignancies and usually involves cecum or rectum. The aim of this paper is to present the role and the importance of double contrast bariumenema (DCBE) in the diagnostic process. Case report. A 77 years old malewas admitted because of suspected inflammation in the area of total endoprosthesis of the left hip, inserted ten years before. Listeria monocytogenes was isolated from the aspirate and the patient treated with antibiotics. Twenty years ago the patient underwent nephrectomy because of hypernephroma of left kidney. At the time of admission he had sideropenic anaemia and he was febrile. Conclusion. The patient underwent many diagnostic procedures: ultrasound (US), computed tomography (CT), double contrast barium enema, which showed a tumour in the cecum, small bowel follow-through and scintigraphy. The diagnosis of primary non-Hodgkin lymphoma was established byhistology after biopsy at colonoscopy. Objavljeno v DiRROS: 31.01.2024; Ogledov: 275; Prenosov: 67 Celotno besedilo (80,69 KB) |
1989. Relevance of inter-particle interaction in directed energy deposition powder streamTijan Mede, Matjaž Godec, 2024, izvirni znanstveni članek Povzetek: Blown powder dynamics is one of the aspects of Directed Energy Deposition (DED) with a major influence on deposition quality and potential for improvement in simulation. Most currently employed computational models discard powder grain collisions as negligible, although little explicit evidence for that claim exists. A Discrete Element Method approach is thus employed in the present work to simulate the actual number of grain collisions in a powder stream of a commercial discrete coaxial nozzle and how that number varies with the key processing parameters. While the number of powder grain collisions is found to in fact be negligible at one side of the usable parameter spectrum, the opposite side results in as many as 84% of all the powder grains being involved in inter-granular collisions with an average rebound angle of 14◦, challenging the established hypothesis of the negligibility of this phenomena. Ključne besede: DED, powder stream, grain collisions, DEM Objavljeno v DiRROS: 31.01.2024; Ogledov: 266; Prenosov: 139 Celotno besedilo (1,65 MB) Gradivo ima več datotek! Več... |
1990. Environment and breast cancer - the role of xenooestrogens in breast cancerAndrej Plesničar, Branko Družina, Viljem Kovač, Božo Kralj, 2002, izvirni znanstveni članek Povzetek: The survival rate of breast cancer patients has not changed much in the last few decades in developed countries. In order to improve the efficacy of breast cancer prevention and treatment, the role of xenooestrogens in the mechanisms of its development has been evaluated. These industrial chemical bear little structural resemblance to each other and bind to the oestrogen receptors of exposed cells and/or trigger oestrogenic responses in laboratory test systems. Exposure to xenooestrogens has been regarded as a risk factor for carcinogenesis and a preventable cause of breast carcinoma. Several epidemiological and experimental studies in in vivo and in vitro conditions of the influence of xenooestrogens on the occurrence of breast cancer have been conducted in the last decades and have shown ambiguous results. No increase of breast carcinoma incidence could be found in women who were exposed to relatively high concentrations of xenooestrogens for extended periods and small quantities of these compounds that are present in the environment probably cannot act as etiological agents for the occurence of this disease. A multi step approach is suggested regarding the sequence of studies and measures that should be taken to further assess the importance of xenooestrogens on breast cancer carcinogenesis. Ključne besede: dojka, ksenoestrogeni, novotvorbe Objavljeno v DiRROS: 31.01.2024; Ogledov: 319; Prenosov: 72 Celotno besedilo (96,95 KB) |