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Maternal beliefs about children and adolescents’ academic achievement: Gender and school level differences
No full textDördüncü Tipo(morfo)loji: Christopher C. M. Lee’nin Tipolojik Şehirciliği ve Tipomorfoloji
No full textAldo Rossi’nin “Şehrin Mimarisi” kuramına mimarlık ve şehircilikte sıklıkla atıftabulunulmasının nedenlerinden biri de, tarihi Avrupa kentinde var olanancak Batılı olmayan çağdaş kentte eksikliği hissedilen mekânsal değerlerinsüregelen arayışıdır. Ancak, “tabula rasa” yaklaşımıyla hızla şehirleşengelişmekte olan ülkelerdeki kentleri daha etkin biçimde kavrayabilmek içinbaşlangıçta tarihi kentleri okumak amacıyla geliştirilen “kolektif bellek,”“genius loci” ve “kentsel artifakt” gibi kavramların yeniden ele alınması gerekir.Yirmi birinci yüzyıl kenti bağlamında tip ve tipoloji kavramlarının öneminisavunan Christopher C. M. Lee, Rossi’nin ortaya koyduğu kuramsal çerçeveyi,hızlı şehirleşen çağdaş kentleri de açıklayacak şekilde güncellemeyegirişir. Lee, Rossi’nin “Şehrin Mimarisi”” kuramını yapıbozumuna uğratarak“kentsel artifakt”ı “baskın tip”e ve “tarihi kenti” “gelişimsel kent”e dönüştürürve “Şehrin Fikri”” adıyla yeniden kurgular. Söz konusu kavramlar, Lee’ninArchitectural Association Mimarlık Okulunda mimari tasarım eğitimiverdiği yıllarda biçimlenen, Berlage Enstitüsü ve TU Delft’te yürüttüğüdoktora çalışmalarıyla entellektüel olarak olgunlaşan ve Harvard GSD’deverdiği seminerler ve tasarım stüdyolarında rafine ettiği “DördüncüTipoloji” adını verdiği kuramsal çerçevesinin tam merkezinde yer alır.Her ne kadar Lee, çalışmalarında kentsel morfoloji veya tipomorfolojikyaklaşıma doğrudan atıfta bulunmayıp çalışmalarını “Tipolojik Şehircilik”ve “Dördüncü Tipoloji” olarak adlandırsa da, kenti onu var edenbina tipleri üzerinden okuma, kavramsallaştırma ve kuramsallaştırmaçabası, tipomorfolojik yaklaşımla büyük oranda paralellik gösterir.Dolayısıyla Lee’nin kuramsal çerçevesi, sıkça referans verdiği CarloAymonino ve özellikle Aldo Rossi’nin yanı sıra Saverio Muratorive Gianfranco Caniggia’nın çalışmalarını da çağrıştırmaktadır.Benzer şekilde, 2010’lardan bu yana kentsel mimarlığı tip ve tipolojikavramları üzerinden sorgulayan, fakat kendilerini daha çok İtalyanTipomorfoloji Ekolünün Carlo Aymonino ve Aldo Rossi kanadıylailişkilendirip tipomorfolojik yaklaşımın geneliyle aralarında mesafe olanbir araştırmacı topluluğu dikkat çeker. Aralarında Lee’nin de bulunduğubu araştırma topluluğu Architectural Association Mimarlık Okulundakurulan “City as a Project” araştırma kolektifi etrafında şekillenir.Bu bildiri, Lee’nin ortaya attığı kuramsal çerçeveyi tipomorfolojik yaklaşımıntemel kavramlarıyla karşılaştırarak, zaman içinde farklı yönlere savrulmuşolsa da aslında aynı konuya odaklanan ve benzer kaynaklardan besleneniki aktif araştırma topluluğu arasında kuramsal bir köprü kurmayı hedefler.Böylelikle, merkezinde ISUF’un bulunduğu, bilimsel etkinlikleri ve yayınlarıdaha periyodik olan ilk araştırma topluluğu ile; çalışmalarını dönem dönemdüzenledikleri bilimsel etkinlikler ile derleme kitaplar ve dergilerin tematiksayıları gibi yayınlarla duyuran ikinci araştırma topluluğu arasında bir takımkuramsal süreklilikler kurmaya çalışır. Lee’nin yayımlanmış araştırmaları,yayımlanmamış doktora tezi ve kendisiyle yapılan bir röportajdan yolaçıkan bildiri ayrıca, Lee’nin kuramsal çerçevesini tipomorfolojik yaklaşımınbir parçası olarak kabul etmenin, bu yaklaşımın gelişmekte olan dünyaülkelerindeki kentsel bağlamlara uygulanabilirliğini artırabileceğini öne sürer. “ANAHTAR KELİMELER: Baskın tip, Christopher C. M. Lee, gelişimsel kent,tipolojik şehircilik, tipomorfoloji</div
Predicting system dynamics of pervasive growth patterns in complex systems
No full textPredicting dynamic behaviors is one of the goals of science in general as well as essential to many specific applications of human knowledge to real world systems. Here, we introduce an analytic approach using the sigmoid growth curve to model the dynamics of individual entities within complex systems. Despite the challenges posed by nonlinearity and unpredictability, we demonstrate that sigmoid-like trajectories frequently emerge in systems where entities undergo phases of acceleration and deceleration of growth. Through case studies of (1) customer purchasing behavior and (2) U.S. legislation adoption, we show that these patterns can be identified and used to predict an entity’s ultimate state well in advance of reaching it. This provides valuable insights for business leaders and policymakers. Moreover, our characterization of individual component dynamics offers a framework to reveal the aggregate behavior of the entire system. Moreover, our classification of entity lifepaths contributes to understanding system-level structure by revealing how individual-level dynamics scale to aggregate behaviors. This study offers a practical modeling framework that captures commonly observed growth dynamics in diverse complex systems and supports predictive decision-making
Climate change drove Late Miocene to Pliocene rise and fall of C4 vegetation at the crossroad of Africa and Eurasia (Anatolia, Türkiye)
No full textCharacterization of Flow Structure and Wall Shear Stress in Patient-Specific Abdominal Aortic Aneurysm Phantom Using Particle Image Velocimetry
No full textAbdominal aortic aneurysm (AAA) is an irreversible dilation of the abdominal aorta that carries a significant risk of rupture if not adequately screened and treated. This condition poses a severe threat, with a mortality rate exceeding 80% in certain age groups. The enlargement of the abdominal aorta leads to notable hemodynamic alterations in AAAs, characterized by flow separation and vortical structures. Current understanding acknowledges a correlation between the growth and rupture mechanisms of AAA and the disturbed hemodynamics, emphasizing metrics such as time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), endothelial cell activation potential (ECAP), and relative residence time (RRT). In this study, we utilized a quantitative velocity measurement technique, particle image velocimetry (PIV), to characterize the flow structure and wall shear stress in a patient-specific aneurysmal abdominal aorta phantom. AAA phantoms generated from patient computed tomography (CT) images were used. Phase-averaged flow fields for 12 phases of physiological flow were investigated, and velocity contours, streamline patterns, and swirling strength contours were constructed in the AAA at three different PIV planes. A method previously developed and validated to extract wall shear stress from PIV measurements is applied to obtain shear stress indexes, including TAWSS, OSI, ECAP, and RRT. In addition, to link our findings with the clinical rupture risk, actual rupture location in the CT images of the aneurysm sac for the studied case was compared with the flow structure and shear stress distributions obtained from PIV measurements. The progression of vortex structures in the bulge along with the flow separation and reattachment zones in relation to the shear stress indexes are presented and discussed in detail. When flow dynamics in actual rupture location is analyzed, there is a high level of flow disturbance characterized by flow circulation, low TAWSS, and high OSI, ECAP, and RRT, consistent with previous studies. Here, we present a PIV-based flow examination through patient-specific phantom, which will contribute to experimental investigations for understanding the influence of disturbed hemodynamics on AAA biomechanics
Drastic Impact of Donor Substituents on Xanthenes in the PDT of Glioblastoma
No full textEven though significant progress has been made in treating various cancer types, brain cancers lag drastically. Several factors contribute, led by operational difficulties, the blood-brain barrier, and the tendency of recurrence. Alternative therapies are needed, and photodynamic therapy (PDT) offers several advantages. However, PDT has rarely been explored for brain cancers since, for achieving near-infrared range activation, photosensitizers should have longer conjugation lengths and thus higher molecular weight, which then limits blood-brain barrier penetration. Here, we describe the syntheses and PDT action of two new selenium-containing xanthane-based photosensitizers (NSeMorph and NSeAze) that show absorption over 650 nm with molecular weights lower than 420 g/mol. It has been demonstrated that both NSeMorph and NSeAze showed PDT activity against glioblastoma cell lines (U87MG and U118MG), and more interestingly, the efficacy and selectivity of the photosensitizers were significantly different depending on the donor side groups. NSeMorph, utilizing morpholine donors, showed IC50 values of 15.8 mu M for U87MG and 8.0 mu M for U118MG cell lines. Surprisingly, the IC50 was not reached at a 20 mu M concentration in the healthy cell line (L929), indicating the selective nature of NSeMorph even though no activation-based cage groups or targeting groups were present. Upon switching the donor units to azetidine, IC50 values of 456 nM for U87MG and 461 nM for U118MG cell lines were achieved; to the best of our knowledge, these are the lowest IC50 values reported in literature against glioblastoma (U87MG and U118MG) that combine NIR absorption in aqueous media and low molecular weight (<400 g/mol). Additionally, NSeAze showed one of the highest phototoxicity indices, the ratio of cell viabilities under dark and light conditions, showing the remarkable activity of NSeAze under illumination. Overall, this study represents one of the first examples of the drastic effect on PDT action by altering only the donor side groups of xanthene-based dyes
Measurement of the inelasticity distribution of neutrino-nucleon interactions for 80 GeV < Eν <560 GeV with IceCube DeepCore
No full texte report a study of the inelasticity distribution in the scattering of neutrinos of energy 80-560 GeVoffnucleons. Using atmospheric muon neutrinos detected in IceCube's sub-array DeepCore during 2012-2021, we fit the observed inelasticity in the data to a parameterized expectation and extract the values thatdescribe it best. Finally, we compare the results to predictions from various combinations of perturbativeQCD calculations and atmospheric neutrino flux model
