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Publication Metadata only “Beware the young doctor and the old barber”: development and validation of a job age-type spectrum(Elsevier, 2021) Reeves, Michael Dennis; Fritzsche, Barbara Ann; Smith, Nicholas Anthony; Ng, Yin Lu; Department of Business Administration; Marcus, Justin; Faculty Member; Department of Business Administration; College of Administrative Sciences and Economics; 124653Taking a worker-centric approach, with evidence based on the experiences of working individuals, the current study examines the age-related stereotypes of jobs, the characteristics of age-stereotyped jobs, and the consequences of occupying them. In Study 1, we utilize samples of working adults from the US, Turkey, and Malaysia to establish validation evidence for a spectrum of 160 jobs (n = 123 raters per job). Study 1 findings indicate that entry-level jobs and jobs requiring manual labor or the use of technology are younger-typed, whereas senior level jobs and jobs requiring large investments in training or education are older-typed. The age-typing of jobs was found to be similar across countries for the vast majority of jobs. We then provide criterion validity evidence in Study 2, by testing the interactive effects of chronological age, job age-type, and sex on psychological age and perceived age and sex discrimination across samples of workers from these same three countries (n = 1469). Results upheld theoretical predictions based upon career timetables theory, prototype matching theory, and intersectional salience of ageism theory. The interactive effects of chronological age and job age-type were stronger for women than for men; the hypothesized patterns of effects were overall consistent for women but not for men.Publication Metadata only “Doing What Matters in Times of Stress” to decrease psychological distress during Covid-19: a rammed controlled pilot trial(Wolters Kluwer Medknow Publications, 2022) Uygun, Ersin; Karaoğlan Kahiloğulları, Akfer; Department of Psychology; Department of Psychology; N/A; Acartürk, Ceren; Kurt, Gülşah; İlkkurşun, Zeynep; Faculty Member; Teaching Faculty; Master Student; Department of Psychology; College of Social Sciences and Humanities; College of Social Sciences and Humanities; Graduate School of Social Sciences and Humanities; 39271; 368619; N/ADespite the increasing psychological distress during Covid-19, utilisation of face-to-face psychological interventions decreased profoundly. The aim of this study involving two parallel, two-armed pilot randomised controlled trials was to examine the effectiveness of a guided self-help intervention "Doing What Matters in Times of Stress" (DWM) in decreasing psychological distress in Turkish and Syrian participants. Seventy-four Turkish nationals and 50 Syrian refugee adults with psychological distress were randomly allocated to a DWM group or wait-list control group. The primary outcome measure was the Patient Health Questionnaire 9 postintervention. Secondary outcome measures were the Generalised Anxiety Disorder Scale, posttraumatic stress disorder (PTSD) Checklist for DSM-5, Generalized Self-Efficacy Scale and Acceptance and Action Questionnaire-II postintervention. Although this study was not powered to detect a significant effect for DWM postassessment between DWM and the control group, results showed a significant improvement in depression symptoms among Turkish participants in the DWM group (d = 0.46) and in PTSD symptoms among Syrian participants in the DWM group (d = 0.67) from pre- to postintervention assessment. These results indicate the potential of DWM to decrease mental health problems during the pandemic and importance of a fully powered, definitive controlled trial to examine its effectiveness both for the host community and refugees to reduce psychological distress during Covid-19.Publication Metadata only “Smart poisoning” of Co/SiO2 catalysts by sulfidation for chirality-selective synthesis of (9,8) single-walled carbon nanotubes(2016) Yuan, Yang; Karahan, H. Enis; Wei, Li; Zhai, Shengli; Lau, Raymond; Chen, Yuan; N/A; Yıldırım, Cansu; Birer, Özgür; Master Student; Researcher; Koç University Surface Science and Technology Center (KUYTAM) / Koç Üniversitesi Yüzey Teknolojileri Araştırmaları Merkezi (KUYTAM); N/A; N/A; N/AThe chirality-selective synthesis of relatively large (diameter > 1 nm) single-walled carbon nanotubes (SWCNTs) is of great interest for a variety of practical applications, but only a few catalysts are available so far. Previous studies suggested that S (compounds) can enhance the chirality-selectivity of Co catalysts in SWCNT synthesis, however, the mechanism behind is not fully understood, and no tailorable methodology has yet been developed. Here, we demonstrate a facile approach to achieve the chirality-selective synthesis of SWCNTs by the sulfidation-based poisoning of silica-supported Co catalysts using a mixture of H2S and H2. The UV-vis-NIR, photoluminescence, and Raman spectroscopy results together show that the resulting SWCNTs have a narrow diameter distribution of around 1.2 nm, and (9,8) nanotubes have an abundance of ∼38% among the semiconducting species. More importantly, the carbon yield achieved by the sulfided catalyst (2.5 wt%) is similar to that of the nonsulfided one (2.7 wt%). The characterization of the catalysts by X-ray diffraction, X-ray photoelectron spectroscopy, X-ray fluorescence, and H2 temperature-programmed reduction shows that the sulfidation leads to the formation of Co9S8 nanoparticles. However, Co9S8 nanoparticles are reduced back to regenerate metallic Co nanoparticles during the synthesis of SWCNTs, which maintain a high carbon yield. In this process, Co9S8 nanoparticles seemingly intermediate the production of Co nanoparticles with narrow size distribution. Due to the fact that the poisoning step improves the quality of the end-product rather than hampering the growth process, we have coined the process developed as “smart poisoning”. This study not only reveals the mechanism behind the beneficial role of S in the selective synthesis of relatively large SWCNTs but also presents a promising method to create chirality-selective catalysts with high activity for scalable synthesis.Publication Open Access "Whole" vs "fragmented" approach to EAACI pollen season definitions: a multicenter study in six Southern European cities(Wiley, 2020) Hoffmann, Tara Maria; Şahin, Aydan Acar; Aggelidis, Xenophon; Arasi, Stefania; Barbalace, Andrea; Bourgoin, Anne; Bregu, Blerina; Brighetti, Maria Antonia; Caeiro, Elsa; Sozmen, Sule Caglayan; Caminiti, Lucia; Charpin, Denis; Couto, Mariana; Delgado, Luis; Businco, Andrea Di Rienzo; Dimier, Claire; Dimou, Maria, V; Fonseca, Joao A.; Göksel, Özlem; Güvensen, Aykut; Hernandez, Dolores; Jang, Dah Tay; Kalpaklıoğlu, Füsun; Lame, Blerta; Llusar, Ruth; Makris, Michael P.; Mazon, Angel; Mesonjesi, Eris; Nieto, Antonio; Pahus, Laurie; Pajno, Giovanni Battista; Panasiti, Ilenia; Panetta, Valentina; Papadopoulos, Nikolaos G.; Pellegrini, Elisabetta; Pelosi, Simone; Pereira, Ana Margarida; Pereira, Mariana; Pinar, Munevver; Pfaar, Oliver; Potapova, Ekaterina; Priftanji, Alfred; Psarros, Fotis; Sfika, Ifigenia; Suarez, Javier; Thibaudon, Michel; Travaglini, Alessandro; Tripodi, Salvatore; Verdier, Valentine; Villella, Valeria; Xepapadaki, Paraskevi; Matricardi, Paolo M.; Dramburg, Stephanie; Öztürk, Ayşe Bilge; Saçkesen, Cansın; Yazıcı, Duygu; Faculty Member; Faculty Member; PhD Student; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); School of Medicine; Graduate School of Health Sciences; Koç University Hospital; 147629; 182537; N/ABackground: the adequate definition of pollen seasons is essential to facilitate a correct diagnosis, treatment choice, and outcome assessment in patients with seasonal allergic rhinitis. A position paper by the European Academy of Allergy and Clinical Immunology (EAACI) proposed season definitions for Northern and Middle Europe. Objective To test the pollen season definitions proposed by EAACI in six Mediterranean cities for seven pollen taxa. Methods: as part of the @IT.2020 multi-center study, pollen counts for Poaceae, Oleaceae, Fagales, Cupressaceae, Urticaceae (Parietaria spp.), and Compositae (Ambrosia spp., Artemisia spp.) were collected from January 1 to December 31, 2018. Based on these data, pollen seasons were identified according to EAACI criteria. A unified monitoring period for patients in AIT trials was created and assessed for feasibility. Results: the analysis revealed a great heterogeneity between the different locations in terms of pattern and length of the examined pollen seasons. Further, we found a fragmentation of pollen seasons in several segments (max. 8) separated by periods of low pollen counts (intercurrent periods). Potential monitoring periods included often many recording days with low pollen exposure (max. 341 days). Conclusion: the Mediterranean climate leads to challenging pollen exposure times. Monitoring periods for AIT trials based on existing definitions may include many intermittent days with low pollen concentrations. Therefore, it is necessary to find an adapted pollen season definition as individual solution for each pollen and geographical area.Publication Open Access #COVID19 and #Breastcancer: a qualitative analysis of tweets(Multidisciplinary Digital Publishing Institute (MDPI), 2022) Naganathan, G.; Cleland, J.; Reel, E.; Cil, T.; Bilgen, İdil; School of MedicineRapid and efficient communication regarding quickly evolving medical information was paramount for healthcare providers and patients throughout the COVID-19 pandemic. Over the last several years, social media platforms such as Twitter have emerged as important tools for health promotion, virtual learning among healthcare providers, and patient support. We conducted a qualitative thematic content analysis on tweets using the hashtags #BreastSurgery, #BreastCancer, #BreastOncology, #Pandemic, and #COVID19. Advocacy organizations were the most frequent authors of tweets captured in this dataset, and most tweets came from the United States of America (64%). Seventy-three codes were generated from the data, and, through iterative, inductive analysis, three major themes were developed: patient hesitancy and vulnerability, increased efforts in knowledge sharing, and evolving best practices. We found that Twitter was an effective way to share evolving best practices, education, and collective experiences among key stakeholders. As Twitter is increasingly used as a tool for health promotion and knowledge translation, a better understanding of how key stakeholders engage with healthcare-related topics on the platform can help optimize the use of this powerful tool.Publication Metadata only ‘Anti-commutable’ local pre-Leibniz algebroids and admissible connections(Elsevier, 2023) Department of Physics; N/A; Dereli, Tekin; Doğan, Keremcan; Faculty Member; PhD Student; Department of Physics; College of Sciences; Graduate School of Sciences and Engineering; 201358; N/AThe concept of algebroid is convenient as a basis for constructions of geometrical frameworks. For example, metric-affine and generalized geometries can be written on Lie and Courant algebroids, respectively. Furthermore, string theories might make use of many other algebroids such as metric algebroids, higher Courant algebroids, or conformal Courant algebroids. Working on the possibly most general algebroid structure, which generalizes many of the algebroids used in the literature, is fruitful as it creates a chance to study all of them at once. Local pre-Leibniz algebroids are such general ones in which metric-connection geometries are possible to construct. On the other hand, the existence of the 'locality operator', which is present for the left-Leibniz rule for the bracket, necessitates the modification of torsion and curvature operators in order to achieve tensorial quantities. In this paper, this modification of torsion and curvature is explained from the point of view that the modification is applied to the bracket instead. This leads one to consider 'anti-commutable' local pre-Leibniz algebroids which satisfy an anti-commutativity-like property defined with respect to a choice of an equivalence class of connections. These 'admissible' connections are claimed to be the necessary ones while working on a geometry of algebroids. This claim is due to the fact that one can prove many desirable properties and relations if one uses only admissible connections. For instance, for admissible connections, we prove the first and second Bianchi identities, Cartan structure equations, Cartan magic formula, the construction of Levi-Civita connections, the decomposition of connection in terms of torsion and non-metricity. These all are possible because the modified bracket becomes anti-symmetric for an admissible connection so that one can apply the machinery of almost-or pre-Lie algebroids. We investigate various algebroid structures from the literature and show that they admit admissible connections which are metric-compatible in some generalized sense. Moreover, we prove that local pre-Leibniz algebroids that are not anti-commutable cannot be equipped with a torsion-free, and in particular Levi-Civita, connection.Publication Metadata only (Bis)phosphonic acid-functionalized poly(ethyleneimine)- poly(amido amine)s for selective in vitro transfection of osteosarcoma cells(Amer Chemical Soc, 2021) Güven, Melek Naz; Altuncu, Seçkin; Konca, Yeliz Utku; Avcı, Duygu; N/A; Department of Chemistry; Demirci, Gözde; Acar, Havva Funda Yağcı; Master Student; Faculty Member; Department of Chemistry; Graduate School of Sciences and Engineering; College of Sciences; N/A; 178902Osteosarcoma is aggressive bone cancer, whose treatment has not changed significantly for the past few decades. Although gene therapy methods have emerged as potential treatment routes, the need for efficient and nontoxic gene delivery systems targeting osteosarcoma cells remains a challenge. High-molecular-weight poly(ethyleneimine)s (PEIs) are used as universal transfection agents; however, they cause significant cytotoxicity. on the other hand, poly(amido amine)s (PAAs) are biocompatible, biodegradable polymers with promising transfection efficiency, which should be improved further. In this paper, we combined low-molecular-weight branched PEI (1800 Da) and PAA macromers functionalized with various amounts of (bis)phosphonic acid groups and pentanol (via 5-amino-1-pentanol (AP)). The (bis)phosphonic acid groups on these polymers (PAEIs) are intended to facilitate bone targeting. The molecular weights of the PAEI polymers were between 2600 and 8600 g/mol. Their cytotoxicities and green fluorescence protein (GFP) transfection efficiencies were tested on an osteosarcoma cell line (U-2 OS cells), which is challenging to transfect, and healthy muscle cells (C2C12). Both the cytotoxicity and transfection efficiency of PAEIs were affected by the phosphonic acid (via APA, 2-aminoethyl phosphonic acid) or bisphosphonic acid (via ALE, sodium alendronate) content of the polymers. PAEIs are more cytocompatible than both linear and branched 25 kDa PEI. ALE-containing PAEIs provided better transfection than APA-containing ones. The most efficient PAEI polymer, containing a 0.7:0.3 AP/ALE ratio, displayed a transfection efficiency that was five times higher than that of 25 kDa PEI with dramatically better cytocompatibility. This is comparable to FuGENE, but PAEI is more advantageous in selective transfection of the U-2 OS. This set of polymers may be promising candidates for targeted gene therapy of osteosarcoma.Publication Metadata only (Im)moral borders in practice(Taylor & Francis, 2021) El Qadim, Nora; Isleyen, Beste; de Vries, Leonie Ansems; Hansen, Signe Sofie; Lisle, Debbie; Simonneau, Damien; N/A; Karadağ, Sibel; Researcher; Migration Research Program at Koç University (MIReKoç) / Göç Araştırmaları Uygulama ve Araştırma Merkezi (MIReKoç); N/A; N/AThis Forum aims to push existing debates in critical border and migration studies over the featuring of morals, ethics and rights in everyday practices relating to the governance of the mobility of non-citizen populations. Its contributors steer away from the actual evaluation or advocacy of the good/just/ethical, focusing instead on the sociological examination of morals and ethics in practice, i.e. how actors understand morally and ethically the border and migration policies they implement or resist. A proliferating interest in the discursive and non-discursive materialisation of moral and ethical elements in asylum and migration policies has examined the intertwinement of care and control logics underlying the management of refugee camps, borders and borderzones, and hotspots alongside the deployment of search-and-rescue operations. Nevertheless, recent research has shown the need to unpack narratives and actions displaying values and symbols that are not necessarily encompassed within this intertwinement of compassion and repression. We argue that there is a need to pay more attention to the diversity, plurality and the operation of morality, ethics and rights in settings and geographies, and of including a diversity of actors both across and beyond EUrope.Publication Metadata only (Post) humanist tangles in social ecology and new materialism(Palgrave, 2017) Department of Comparative Literature; Ergin, Meliz; Faculty Member; Department of Comparative Literature; College of Social Sciences and Humanities; 101428This chapter argues that entanglements lie at the core of two prominent schools of ecological thought: social ecology and new materialism. While social ecology, spearheaded by Murray Bookchin, stresses the tangle of ecological and socio-political issues and advocates for a transformative viewpoint in both spheres, new materialism destabilizes the nature/culture dichotomy by reading the production of matter and meaning as co-extensive praxes and by defining phenomena, in Karen Barad’s terms, as the “ontological inseparability of intra-acting agencies.” Ergin reads social ecology and new materialism, respectively, in relation to deconstruction to tease out the different models of entanglement in each school of thought and to elucidate what is at stake in the motif of entanglement. She rethinks these three strands of thought vis-à-vis each other to capture some of the breadth and variety in reconceptualizations of natural-social and material-discursive entanglements.Publication Metadata only 1,3-bis(gamma-aminopropyl)tetramethyldisiloxane modified epoxy resins: curing and characterization(Elsevier, 1998) Department of Chemistry; Department of Chemistry; Yılgör, Emel; Yılgör, İskender; Researcher; Faculty Member; Department of Chemistry; College of Sciences; College of Sciences; 40527; 24181Incorporation of siloxane oligomers with reactive organofunctional terminal groups, such as amine, epoxy and carboxy, into the structure of epoxy networks, provides improvements in the fracture toughness, water absorption and surface properties of the resultant systems. 1,3-bis(gamma-aminopropyl) tetramethyldisiloxane (DSX) was used as a model curing agent and modifier in bis(4-aminocyclohexyl)methane (PACM-20) cured diglycidyl ether of bisphenol-A (DGEBA) based epoxy resins. Curing reactions followed by differential scanning calorimetry indicated faster reaction rates between DSX and DGEBA as compared with PACM-20 and DGEBA. Mechanical characterization of the modified products showed improvements in tensile and impact strengths as expected. Glass transition temperatures of these materials showed a decrease with an increase in DSX content.