123903 research outputs found
Sort by
Phospholipid profiling
No full textThe use of lecithin as an emulsifier in food supplements has increased in recent years. However, successful formation of liposomes or micelles requires an appropriate mixture of phospholipids in lecithin. To evaluate the emulsification properties of lecithin for food supplements, a reliable analytical procedure for characterizing phospholipids is necessary. A liquid chromatography–mass spectrometry method was developed to identify phospholipids in lecithin without standard reference materials. For efficient separation of phospholipids before mass spectrometric analysis, a reverse-phase high-performance liquid chromatography method was optimized using a Waters XBridge Protein BEH C4 column. The optimized chromatographic method demonstrated good linearity and precision. Molecular ions were detected in full scan mode to determine accurate mass-to-charge ratios for individual peaks in the chromatogram. A custom Python program was then used to generate a list of possible phospholipid species for each peak based on the measured mass-to-charge ratios. Tandem mass spectrometry was performed to confirm the identity of specific phospholipids by comparing experimental fragmentation patterns with theoretical predictions. Identification of the phospholipids was also confirmed with four commercially available standard reference compounds, demonstrating the reliability of the proposed approach. The developed method offers a practical and cost-effective strategy for identifying phospholipids in complex matrices, especially when standard reference compounds are unavailable. Additionally, it enables targeted selection of standard compounds for future quantitative analyses, making it a valuable tool for comprehensive lipid profiling
Theoretical and experimental investigation on microcosmic surface generation in precision grinding with discrete method
No full textSurface topography of the workpiece created in precision grinding is influenced by not only key process parameters, but also the distribution characteristics of active abrasive grits on the surface of the grinding wheel, including the number of active grits in the contact zone, the morphology of grits, and the cutting depth of a single grit in a normal direction. Under the conditions of small cutting depth (less than 5 μm) with small eccentrical rotation of the abrasive wheel (less than 3 μm), the influences of the original workpiece surface topography characteristics and the dynamic cutting depth of abrasive grits are often neglected in the study of microcosmic surface generation. In this paper, a discrete method (DM) is used to develop a theoretical kinematics model for the prediction of machined workpiece surface topography. Compared with the characteristics value of surface topography (scratch grooves) between experimental measurement and simulation output, the verification results from the improved prediction model of surface topography present well in comprehensively considering the influences of original surface characteristics, eccentrically rotational behavior of the abrasive wheel and the overlapped situation of scratch grooves on complex process conditions with a prediction error of about 10 %. In comparison with two commonly used empirical formulas in many other research studies, the prediction accuracy of the DM model for machined surface topography improves by 20 %. When calculating material removal volume, the prediction accuracy of incremental volume model of material removal increases approximately by 9 % to 19 % in comparison with the prediction results that take the whole cross-section area of an active grit as a key variable.Topografija površine obdelovanca, ustvarjena pri preciznem brušenju, je odvisna ne le od ključnih procesnih parametrov, temveč tudi od porazdelitvenih značilnosti aktivnih abrazivnih zrn na površini brusnega kolesa, vključno s številom aktivnih zrn v kontaktni coni, njihovo morfologijo in globino reza posameznega zrna v normalni smeri. Pri majhnih globinah reza (manj kot 5 μm) in majhnih ekscentričnih rotacijah brusnega kolesa (manj kot 3 μm) se vplivi prvotne topografije površine obdelovanca ter dinamične globine reza abrazivnih zrn pogosto zanemarjajo pri proučevanju mikroskopske tvorbe površine. V tem članku je uporabljena diskretna metoda (DM) za razvoj teoretičnega kinematičnega modela za napoved topografije obdelane površine. Primerjava med izmerjenimi in simuliranimi vrednostmi značilnosti topografije (prask) je pokazala, da izboljšani napovedni model topografije površine dobro zajame vplive začetne površinske topografije, ekscentričnega vrtenja brusnega kolesa ter prekrivanja prask pri kompleksnih procesnih pogojih, z napako napovedi približno 10 %. V primerjavi z dvema pogosto uporabljenima empiričnima enačbama se natančnost napovedi modela DM za topografijo obdelane površine izboljša za 20 %. Pri izračunu volumna odstranjenega materiala se natančnost napovedi inkrementalnega volumskega modela odstranitve materiala poveča za približno 9 % do 19 % v primerjavi z rezultati napovedi, ki kot ključno spremenljivko upoštevajo celotno presečno površino aktivnega zrna
Upor proti tehnološki odvisnosti z Mencijem
No full textIn the attention economy, technology companies derive their primary profits not from direct content consumption but from advertising revenue generated by capturing users’ attention. This relentless pursuit of attention has led to widespread issues of addiction to social media, pornography, and video games across the world. This problem cannot be addressed by individual willpower alone, as advanced technologies and design techniques are deliberately crafted to exploit human psychology and foster addictive behaviours. To address this issue, we must move away from both rugged individualism and oppressive patriarchy. Mencian ethics, particularly his principle of “don’t forget, don’t force”, offers a valuable model. According to this approach, we should focus on collectively creating environments that foster healthy digital habits, rather than placing the burden solely on individuals or resorting to forceful behaviour modification. This environment must be nurtured by all family members. Beyond the family, we must also work to cultivate a healthy digital culture in society at large.V ekonomiji pozornosti tehnološka podjetja ne ustvarjajo glavnega dobička iz neposredne potrošnje vsebin, temveč iz oglaševalskih prihodkov, ki jih ustvarijo s pritegnitvijo po-zornosti uporabnikov. To nenehno prizadevanje za pozornost je po vsem svetu privedlo do odvisnosti od družbenih medijev, pornografije in videoiger. Te težave ni mogoče rešiti zgolj z individualno voljo, saj so napredne tehnologije in oblikovalske tehnike namerno zasnovane na način, da izkoriščajo človeško psihologijo ter spodbujajo zasvojenost. Da bi primerno obravnavali te težave, se moramo odmakniti od ostrega individualizma in zatiralnega patriarhata. Pri tem Mencijeva etika, zlasti njegovo načelo »ne pozabi, ne vsiljuj«, ponuja dragocen model. V skladu s tem bi se morali osredotočiti na skupno ustvarjanje okolij, ki spodbujajo zdrave digitalne navade, namesto da breme prelagamo izključno na posameznike oziroma se zatekamo k prisilnemu spreminjanju vedenja. To okolje morajo negovati vsi družinski člani. Hkrati si je treba prizadevati tudi za gojenje zdrave digitalne kulture v družbi kot celoti
Earliest galaxy evolution in the CANUCS+Technicolor fields: galaxy properties at seen with the full NIRCam medium- and broadband filters
No full textWe present a sample of galaxies by exploiting some of the richest JWST NIRCam imaging data, taken in the CANUCS survey in Cycle 1 and the Technicolor (TEC) survey in Cycle 2. The combination of the CANUCS+TEC provides multiepoch, deep NIRCam images in all medium bands (MBs) and broad bands (BBs) onboard NIRCam (22 filters in total), over in three independent lines of sight. We select high-z galaxy candidates based on photometric redshifts, and obtain eight candidates at , including a very robust candidate at . The ultraviolet (UV) luminosity function (LF) from our sample is consistent with previous JWST studies showing a scatter of dex across the literature, marking the significance of the field-to-field variance in interpreting galaxy abundance measurements at . We find that the UV LF moderately evolves at , and the LF normalization and the luminosity density decline by a factor of from to , indicating less steep evolution than z 10sim 0.6sim 0.6Deltabeta_{mathrm{UV}} sim −0.3$
magistrsko delo
No full textMagistrska naloga je sestavljena iz treh delov: pisnega dela, ustne analize in magistrskega koncerta, nastala pa je na Oddelku za sakralno glasbo Akademije za glasbo v Ljubljani. Naloga in koncert sta sestavljena iz analiz skladb, ki so hkrati program magistrskega koncerta, vključno z lastno skladbo in improvizacijo na dano temo. Mentor pisnega dela magistrske naloge je doc. Damijan Močnik, koncerta prof. dr. Mario Perestegi, skladateljskega dela oz. lastne skladbe zasl. prof. mag. Ivan Florjanc in improvizacije zasl. prof. Maks Strmčnik. Program koncerta je sestavljen iz skladb in analize starega mojstra Françoisa Couperina (Messe pour les Convents), Johanna Sebastiana Bacha (Preludij in fuga v Es-duru, BWV 552), Césarja Francka (Koral št. 3 v a-molu), Jeana Langlaisa (Incantation pour un jour Saint), Jožeta Trošta (Suite II) in lastne skladbe (Kancone na dano temo v E-duru).The master\u27s thesis consists of three parts: a written part, an oral analysis of the work and a master\u27s concert. It was created at the Department of Sacred Music at the Academy of Music in Ljubljana. The written thesis and the concert consist of analyses of compositions, which also represent the program of the master\u27s concert and include my own composition as well as an improvisation on a given theme. The supervisor of the written part of the master\u27s thesis is Assist. Prof. Damijan Močnik, the supervisor of the concert is Assoc. Prof. Dr. Mario Perestegi, the supervisor of the compositional part, i.e. my own composition, is Prof. Emeritus Mag. Ivan Florjanc and the supervisor of improvisation is Prof. Emeritus Maks Strmčnik. The concert program consists of compositions and analyses by the old master François Couperin (Messe pour les Convents), Johann Sebastian Bach (Prelude and Fugue in E-flat major, BWV 552), César Franck (Chorus No. 3 in A minor), Jean Langlais (Incantation pour un jour Saint), Jože Trošt (Suite II) and my own composition (Canzone on a given theme in E major)
Revidirani podatki o grobovih in grobnih pridatkih s poznoantičnega grobišča Lajh v Kranju (Slovenija)
No full textThe dataset, presented in a data paper (submited), includes data about the Late Antique cemetery Lajh in Kranj (Slovenia), one of the largest burial grounds of the period in the wider region. The dataset combines archaeological, archival, and museum data generated over more than a century of excavations conducted under highly variable methodological conditions. A through revision of field documentation, publications, inventory books, photographs, maps, preserved artefacts and osteological material enabled critical assessment and the reconstruction of grave assemblages and associated finds. The resulting dataset provides a standardised basis for further quantitative, comparative and interdisciplinary research into Late Antique and Early Medieval burial practices.Podatkovna zbirka, predstavljena v podatkovnem članku (oddan), vključuje podatke o poznoantičnem grobišču Lajh v Kranju (Slovenija), enem največjih grobišč tega obdobja v širši regiji. Zbirka združuje arheološke, arhivske in muzejske podatke, ki so nastali v več kot stoletju izkopavanj, izvedenih v zelo različnih metodoloških okoliščinah. Temeljita revizija terenske dokumentacije, objav, inventarnih knjig, fotografij, načrtov, ohranjenih najdb in osteološkega gradiva je omogočila kritično presojo in rekonstrukcijo grobnih celot ter z njimi povezanih najdb. Nastala podatkovna zbirka predstavlja standardizirano osnovo za nadaljnje kvantitativne, primerjalne in interdisciplinarne raziskave poznoantičnih in zgodnjesrednjeveških pogrebnih praks
Science studies with local characteristics
No full textČlanek posebno številko Filozofskega vestnika umesti v stanje raziskav na področju zgodovine in filozofije znanosti. Na eni strani izpostavi pomanjkanje prevoda sociologije znanstvenega spoznanja (SZS) v slovenski epistemologiji, na drugi strani pa opozori na nekatere nerazrešene probleme SZS, na katere se odzivajo nekateri aktualni trendi v študijah znanosti, kot so globalni obrat in pozivi k dekolonizaciji. V odsotnosti koherentnih miselnih šol namen tako ni uvažati rešitev iz tujine, ampak ob posodabljanju izvajati tudi kritiko aktualnih raziskav, glede na katere naj bi se ta posodobitev izvedla, in tako priti do epistemologije z lokalnimi karakteristikami. Orisani so trije metodološki premiki, ki jih članki v številki razvijajo v polemiki z obstoječimi študijami znanosti. Prvič, razširjajo geografski razpon zgodovinskih primerov preučevanih znanstvenih praks ne samo onkraj globalnega severa, ampak tudi onkraj meja nekdanjega angleškega in francoskega imperija. Drugič, pokažejo, da je – navezujoč se na načelo simetrije – mogoče in smiselno z enakimi pristopi analizirati pojmovanja elitnih intelektualcev, jukateških gospodinj, habsburških uradnikov, kranjskih kmetov, zdravnikov, vremenoslovcev ali članov jugoslovanske Zvezne komisije za jedrsko energijo. Tretjič, znanstvenih praks ne obravnavajo le kot antropološkega mikroobjekta, ampak jih vedno preučujejo v povezavi s posebnimi odnosi moči, v katerih se odvijajo.The article situates this special issue of Filozofski vestnik within the state of research in history and philosophy of science. On the one hand, it highlights the lack of translation of sociology of scientific knowledge (SSK) in Slovenian epistemology while, on the other hand, drawing attention to some unresolved problems of SSK that have been addressed by some recent trends in science studies, like the global turn and calls for decolonization. In the absence of coherent schools of thought, the aim of the issue is hence not to import “solutions from abroad,” but to update the discipline in Slovenia while simultaneously appraising the state of international research which should serve as the standard of this modernization, thus arriving at an epistemology with local characteristics. Three methodological shifts are outlined, which the articles in this issue develop in dialogue with established studies of science. First, they expand the geographical scope of case studies not just beyond the Global North, but also beyond the borders of the former British and French empires. Second, building on the principle of symmetry, the same approaches may and are productively used to analyze the conceptions of elite intellectuals, Yucatec housewives, Habsburg officials, Carniolan farmers, doctors, meteorologists, or members of the Yugoslav Federal Commission for Nuclear Energy. Thirdly, scientific practices are not treated merely as anthropological micro-objects, but are examined in connection with the specific power relations in which they unfold
Significance of the deformation capacity of bolts for the performance of bearing-type lap connections
No full textThe study investigates the significance of the deformation capacity of bolts in bolted bearing lap connections, focussing on connections with aligned and misaligned bolt holes. The investigation includes a series of tests on S960 steel lap connections with M12 and M16 bolts of different bolt classes to evaluate the effects of misalignment of bolt holes and the ability of the bolts to redistribute forces. The test results of connections with aligned bolt holes show that the deformation capacity of the bolts was sufficient to equalise the bolt forces. However, the test results of connections with misaligned bolt holes indicate a potential reliability issue in the design of lap bolt connections where the ductility condition is not met, especially for high-strength bolt classes, e.g. 10.9. The connections were characterised by premature failure of the bolt(s) as the deformation capacity of the bolt was used to overcome the misalignment of the bolt holes. These conclusions can be transferred to connections with lower steel grades, such as S235
An unwanted guest in the electrochemical oxidation of high-voltage Li-ion battery electrolytes
No full textLithium-ion batteries (LIBs) are central to the urgent societal need to decarbonize both transportation and energy storage on the grid. Unfortunately, despite their attractive energy/power density, as well as high coulombic and energy efficiencies, further improvement of this technology – especially their durability – is desperately needed. To support these efforts, our study focuses on fundamental understanding of the decomposition pathways for LIB electrolytes at the cathode–electrolyte interface (CEI), as the nature of these reactions directly controls the extent to which cell capacity and voltage decays in these systems. In this study, we employ electrochemical methods, coupled with product analysis using NMR spectroscopy and mass spectrometry, to determine the decomposition mechanisms in both model and technologically relevant electrolytes. Remarkably, we discovered the electrochemical formation of protons with high chemical activity, comparable to known superacids, at potentials relevant to practical Li-ion batteries. Their reactivity toward every individual component of the CEI provides a unified thermochemical origin for a myriad of side reactions that are commonly associated with the electrochemical reaction. In particular, electrochemically generated protons react with intact EC molecules to form CO and other short and long chain ethers. They also undergo an acid–base reaction with LiPF, to form the weaker acid HF, and with the cathode active material, leaching transition metals into the electrolyte. Collectively, the results of this study all point to the urgent need to either mitigate this proton formation or introduce benign harvesting additives via new electrolyte design strategies
Problem of Common Sense in Educational Sciences, Philosophy and Psychoanalysis
No full textV magistrski nalogi obravnavamo problematiko zdravega razuma v pedagogiki, filozofiji in psihoanalizi. Osnovni namen in cilj naloge je predstaviti komparativne zveze, kritično osvetlitev in primerjalno analizo temeljnih pojmov na področju interdisciplinarnega znanstvenega raziskovanja pedagogike, filozofije, psihoanalize in epistemologije. Razpravo pričenjamo z razmejitvijo zgodovine idej od zgodovine znanosti in poudarkom na njuni hkratni povezanosti. Pokažemo, da je za natančno znanstveno raziskovanje potrebno razumeti, da so lahko pojmi, ki so nastajali ob zgodovinsko različnih okoliščinah in pogojih, v današnjem miselnem horizontu in nekem zdravorazumskem razmišljanju drugačni od samega izvornega pojmovnega pomena. V nadaljevanju obravnavamo tri znanstvene revolucije, ki pomenijo spoprijem z zdravim razumom in zaradi katerih se človek v vsakem obdobju znajde v novem svetu mišljenja in življenja. V naslednjem koraku najprej natančno opredelimo pojme: zdravi razum, znanost in znanstvena ideologija. Preciznost teh definicij predstavlja temelj za nadaljnje razumevanje razprave, kjer bomo zaradi boljše ponazoritve in poglobitve obravnavane problematike analizirali tudi besedila, ki govorijo o problematiki zdravega razuma v pedagoškem polju. V tem kontekstu obravnavamo tudi problem zdrave pameti kot mesto boja za univerzalnost, ki terja nenehno razkrinkavanje in kritično dekonstrukcijo.In this Master\u27s thesis, the issue of common sense in educational sciences, philosophy, and psychoanalysis is addressed. The primary purpose and objective of the thesis are to present comparative connections, a critical overview, and a comparative analysis of fundamental concepts within the interdisciplinary scientific research of educational sciences, philosophy, psychoanalysis, and epistemology.
The discussion is initiated by the delineation of the history of ideas from the history of science, with an emphasis placed on their simultaneous interconnectedness. It is demonstrated that for rigorous scientific research, it must be understood that concepts formed under historically different circumstances may differ in today’s intellectual horizon and common-sense reasoning from their original conceptual meanings.
Furthermore, three scientific revolutions are examined, which represent a confrontation with common sense and through which humanity is placed into a new world of thought and life in each period. In the following step, the concepts of common sense, science, and scientific ideology are precisely defined. The precision of these definitions represents the foundation for the further understanding of the discussion, where texts concerning the issue of common sense in the educational sciences field are also analysed to better illustrate and deepen the subject matter.
In this context, the problem of common sense is also treated as a site of struggle for universality, which demands constant exposure and critical deconstruction