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Utilization of ZnO-MgO derived from ferrochrome ash waste as a supercapacitor electrode material
No full textThe present study involved the production of a novel hybrid supercapacitor electrode material ZnO–MgO from ferrochrome ash (FCA) waste using a hydrometallurgical method for the first time in the literature. FCA was initially leached with H2SO4 solutions with varying concentrations and leaching durations at the solid:liquid ratio of 100 g/L. The optimal leaching parameters were determined as 1-M H2SO4 concentration and 60 min, which resulted with the 91.35% of Zn and 31.69% of Mg leaching efficiency. Afterward, the leached ions were precipitated as hydroxides by pH adjustment. Obtained precipitates were subsequently calcined at 500, 750, and 1000 °C to obtain three different ZnO–MgO hybrid materials with various morphological and electrochemical properties. The obtained materials were employed as electrode materials in coin cell-type asymmetric supercapacitors, and the electrochemical performance of the supercapacitors were assessed using CV, GCD, and EIS analyses. The supercapacitor containing the anode calcined at 750 °C exhibited the highest specific capacitance value as 486 mF cm−2 at a scan rate of 10 mV cm−2 and retained 93% of its initial capacitance after 5000 GCD cycles at the current density of 0.5 mA cm−2
Non-simple polyominoes of Kőnig type and their canonical module
No full textWe study the Kőnig type property for non-simple polyominoes. We prove that, for closed path polyominoes, the polyomino ideals are of Kőnig type, extending the results of Herzog and Hibi for simple thin polyominoes. As an application of this result, we give a combinatorial interpretation for the canonical module of the coordinate ring of a sub-class of closed paths, namely circle closed path polyominoes. In this case, we compute also the Cohen-Macaulay type and we show that the coordinate ring is level
Biomimetic 3D bioprinted bilayer GelMA scaffolds for the delivery of BMP-2 and VEGF exogenous growth factors to promote vascularized bone regeneration in a calvarial defect model in vivo
No full textThe effective treatment of critical-sized bone defects requires a coordinated interaction between osteogenesis and angiogenesis. Inspired by natural bone tissue, we developed a bilayer vascularized bone construct using extrusion-based dual 3D bioprinting. The construct consists of two layers: a bone-mimetic layer, which includes highly methacrylated gelatin (GelMAHIGH), hyaluronic acid, alginate, osteoblast cells, and bone morphogenetic protein-2 (BMP-2) loaded polylactic-co-glycolic acid (PLGA) nanoparticles; and a vessel-mimetic layer, composed of low methacrylated gelatin (GelMALOW), alginate, endothelial cells, and vascular endothelial growth factor (VEGF)-loaded PLGA nanoparticles. These layers were designed to form hierarchical microstructures that enable sustained release of growth factor (GF) thereby stimulating both osteogenic and angiogenic processes. The nanoparticles were synthesized using a microfluidic platform, achieving a narrow size distribution. The hydrogel bioinks were systematically optimized for printability, and it was found that incorporation of nanoparticles improved their mechanical properties, surface roughness, degradability, and GF release profiles. Notably, GF release followed zero-order kinetics, ensuring consistent delivery over time. The bilayer scaffolds demonstrated superior cell proliferation and spreading compared to single-layer scaffolds, and in vivo experiments showed enhanced repair of calvarial bone defects. These findings highlight the significant clinical potential of bilayer scaffolds with sequential GF delivery for treating critical-sized bone defects
Correction to: A central limit theorem associated with a sequence of positive line bundles (The Journal of Geometric Analysis, (2025), 35, 3, (86), 10.1007/s12220-025-01921-9)
No full textIn this article, the following corrections were made: Under Lemma 2.2, the following equation was incorrectly given as: “Let {Uj}j=1N be a finite subcover of X. Locally, on each Uj, we have the following representations (Formula presented.) and (Formula presented.) Here [χkj(z)]kj is a positive definite Hermitian matrix, because in a Kähler manifold, we always have a strictly plurisubharmonic local potential function ψ so that (Formula presented.) Similarly, since line bundles Lp are positive, by the definition of positivity, [αkj(z)]kj=[∂2φp∂zj∂zk¯(z)]kj is a positive definite Hermitian matrix, where φp is the corresponding local weight function for hp. Note that in particular αkj(z)∈R for every 1≤k,j≤n. Let us fix some Ul taken from the subcover. By the diophantine approximation condition (2.7) on Ul¯, for any ϵ>0, there exists some p0=p0(ϵ)∈N such that, for all p≥p0, (Formula presented.) for all z∈Ul¯. Take, for example, (Formula presented.) Then (2.11) gives (Formula presented.) Summing this last inequality over idzk∧dzj¯, we have, for all z∈Ul¯⊂X and for all p≥p0 (Formula presented.) which concludes that (Formula presented.) for p≥p0. This will be useful in the proofs of Theorem 4.1 and Theorem 4.2”. Should have been: “Let {Uj}j=1N be a finite subcover of X. Locally, on each Uj, we have the following representations (Formula presented.) and (Formula presented.) Here [χkj(z)]kj is a positive definite Hermitian matrix, because in a Kähler manifold, we always have a strictly plurisubharmonic local potential function ψ so that (Formula presented.) Similarly, since line bundles Lp are positive, by the definition of positivity, [αkj(z)]kj=[∂2φp∂zj∂zk¯(z)]kj is a positive definite Hermitian matrix, where φp is the corresponding local weight function for hp. By using the diophantine approximation (2.8) and the positivity of the above two forms, one can find some large enough p0∈N such that (Formula presented.) for p≥p0. This will be useful in the proofs of Theorem 4.1 and Theorem 4.2”. In the section heading “4.1 Linearization” the following corrections were made: The below sentence has been included: “Fix a point x in X and let us take the coordinates centered at x≡0, Kahler at x, as provided by Lemma 2.2, with coordinate polydisk Pn(x,R) for R>0. Let R′>0 be arbitrary and choose p≫1 so that R′/Ap<R.” The sentence “Ω={(u,v):u,v∈Pn(0,R)}, where p:=Diag[λ1p,…,λnp]” has been corrected to “Ω={(u,v):u∈Pn(0,R′),v∈Pn(0,R′)}⊂Cun×Cvn in the respective coordinates u, v”. The sentence “Ω0:={(u,u¯):u∈Pn(0,R)}” has been corrected to “Ω0:={(u,u¯):u∈Pn(0,R′)}”. The sentence “as p→∞” has been corrected to “on Pn(0,R′)×Pn(0,R′) as p→∞. Therefore, we have proved the next theorem”. The equation number 4.55 has been removed and the below theorem has been included which gives the local uniform convergence: Let (X,ω) be a compact Kähler manifold of complex dimension n and let a sequence of holomorphic line bundles {(Lp,hp)}p≥1 be given, each equipped with a C3-class Hermitian metric hp, satisfying the condition (2.7). Suppose that ηp=‖hp‖31/3Ap→0 as p→∞. Let x be a fixed point in X. Then in the local Kähler coordinates centered at x provided by Lemma 2.2, we have (Formula presented.) locally uniformly on Cun×Cvn as p→∞. In the section heading “5.2 Asymptotic Normality of Random Zero Currents” the sentence “Finally, by the linearization (4.51) on the neighborhood Uj” has been corrected to “Finally, by the linearization (4.51) on the neighborhood Pn(x,R)”. Under the ‘Theorem 1.2’ the equation ||hp||3Ap has been corrected to ||hp||31/3Ap. Under the ‘Theorem 4.1’ the equation ηp=||hp||3Ap has been corrected to ηp=||hp||31/3Ap. Under the ‘Theorem 4.1’ the sentence “By our hypothesis ηp=||hp||3Ap→0” has been corrected to “By our hypothesis ηp=||hp||31/3Ap→0”. Under the ‘Theorem 4.2’ the sentence “Write ηp=||hp||3Ap→0 when p→∞” has been corrected to “Write ηp=||hp||31/3Ap→0 when p→∞”. Under the ‘Theorem 4.2’ the sentence “and by our assumption that ηp=||hp||3Ap→0 when p→∞” has been corrected to “and by our assumption that ηp=||hp||31/3Ap→0 when p→∞”. The original article has been corrected
Usage of 3D-printed scaffolds manufactured with bio-based photopolymer resin via 3D DLP in tissue engineering
No full textIn this study, three-dimensional (3D) printed scaffolds were fabricated using a bio-based photopolymer resin derived from sustainable resources for tissue engineering applications. The resin consisted of a UV-curable bio-based fatty acid-based polyester acrylate, polyethylene glycol dimethacrylate, and a photoinitiator. To enhance porosity and biodegradability, coconut oil and poly(ethylene glycol) (PEG) were incorporated into the formulations. The curing behavior of different formulations was investigated by differential photocalorimetry (Photo-DSC), and it was observed that polyethylene glycol accelerated the curing process. The biocompatibility of the 3D printed scaffolds was evaluated using culture experiments with mouse fibroblast (L-929) cells. The obtained results demonstrate that the developed bio-based photopolymer resins have the potential to be a promising material for tissue engineering applications
Insights into the synthesis and characterization of thiosemicarbazide and urea-based novel isotype II heterojunctions and their competing physicochemical properties in photochemical hydrogen production
No full textOptimizing surface area, light absorption, and band-gap energy of graphitic carbon nitride (g-CN) is crucial for developing efficient hydrogen production photocatalysts. Here, a mass-ratio controlled mix-and-match protocol with precursors, urea and thiosemicarbazide (U and T), is introduced for in situ synthesis of g-CN isotype II heterojunctions (UT-CNs). The specific surface area (SSA), band-gap energy, and product yield of heterostructures were highly mass-ratio-dependent; however, there was no clear systematic trend between the mass ratios and the physicochemical properties. Notably, the heterojunction, synthesized with a low U-ratio (UT3-CN), exhibited a ∼52 % increase in SSA and ∼44 % increase in pore volume compared to bulk T-CN, while light absorption and band-gap energy remained largely unchanged. Despite a 10 % increase in yield compared to bulk U–CN, UT3-CN's SSA decreased by ∼40–50 % at higher U-ratios, and light absorption and yields improved. UT3-CN, with a band gap of ∼2.88 eV, showed three times higher photocatalytic activity for H2 evolution than T-CN (∼2.85 eV) and UT-CN with the narrowest band gap (∼2.59 eV), attributed to high SSA and pore volume, well-ordered structural domains, reduced interlayer spacing, and enhanced charge separation with minimal recombination. The emergence of a sharp X-ray diffraction peak at ca. 2θ = 43.5° in the heterojunctions suggested that structural ordering was influenced by high ammonia gas concentrations and dithiourazole intermediates during thermal decomposition. These findings highlighted the need for mechanistic studies on T decomposition, and this versatile approach offers a promising strategy for fine-tuning photocatalytic properties using a library of g-CN precursors
Bargaining Or Belonging? : Analyzing Gendered Household Time Use Among Turkish Couples
Get PDFThis thesis investigates the tension between economic bargaining power and thesociological pressure of “doing gender” by examining the division of time use withinhouseholds in Türkiye. Drawing on data from the 2014–2015 Turkey Time UseSurvey, the study adopts a two-stage approach that combines econometric analysiswith a theoretical model. The empirical findings indicate that an increase in women’srelative income is associated with a reduction in their share of housework, in linewith bargaining theory. However, this effect is substantially weakened among dualearnercouples. The theoretical model further demonstrates how deeply ingrainedpreferences, such as aversion to housework shaped by gender norms, can constrainthe outcomes of economic bargaining. Overall, the findings suggest that while bothbargaining and belonging influence how couples allocate their time, gender normsoften set the limits on the power of economic negotiation
How Violence In Mexico Has Propped Up The Adolescent Pregnancy Numbers
Get PDFThis thesis investigates the causal impact of the Mexican War on Drugs on adolescentfertility across Mexican municipalities from 2000 to 2019. While nationaladolescent birth rates have declined, localized surges in fertility persist in areasaffected by cartel violence and militarized state interventions. Using Difference-in-Differences and Synthetic Difference-in-Differences (SDID) methods, the study findsthat municipalities with entrenched cartel presence or strategic value to drug traffickingnetworks experienced a significant increase in adolescent fertility followingthe onset of the drug war. The analysis highlights a two-wave fertility response: aninitial rise in historically violent cartel strongholds and a delayed increase in regionslater incorporated into DTO logistics corridors, particularly with the expansion ofthe Cártel de Jalisco Nueva Generación (CJNG). Spatial techniques, including MinimumSpanning Tree and DBSCAN clustering, reveal that these fertility shifts alignwith cartel infrastructure and geographic strategy. These findings underscore howcriminal governance and state militarization reshape demographic behavior and mayundermine human development in conflict-affecte
Constitutionalism And Islam In The SecondConstitutional Period: An Analysis Of Dergezenizade Hasan Rıza’s Şer’-İ Siyâsî Şerh-İ Kânûn-I Esâsî
Get PDFThis thesis focuses on the late Ottoman professional attorney Dergezenizade HasanRıza’s Şer’-’i Siyasi Şerh-i Kanun-ı Esasi, a legal commentary on the Ottoman constitution,to understand a legal professional’s perception of the constitution duringthe Second Constitutional Period. It aims to reconstruct his biography to evaluatehis subjectivity in locating the Ottoman constitution within the siyaset-i şer’iyyeliterature. It also traces siyaset-i şer’iyye back to early examples to understand positionof Hasan Rıza’s commentary in Islamic legal-political thought. Third, it focuseson concepts in the legal commentary, such as caliphate, imamate, maslahat, istihsan,and vahdet. Accordingly, it argues that by articulating a professional outlookon the Ottoman constitution, he seeks ways to formally authorize the constitution,formalize it within the Islamic legitimacy model, and reveal the tension between theshari authority and legal formalism. As a legal professional, by employing siyaset-işer’iyye literature in discussing the Ottoman Constitution, Hasan Rıza interpretsthe constitution not as a Western import and an entirely secular regime. Instead,by locating the constitution within this tradition, it creates a space for rulers andsociety to adhere to principles of unity, justice, and consultation within the frameworkof a constitution based on Sharia. By doing so, he reclaims a sphere of politicsthat aligns with the sharia in the post-Hamidian era, challenges the confinement ofsharia to fıqh by utilizing extra-fıqhi practices in the Islamic discourse
The Formation Of A Constitutional Partnership: Ahmet Emin (Yalman), Ottoman InternationalStudents, And The Transformation OfOttoman-American Relations In The SecondConstitutional Period
Get PDFThe Young Turk Revolution of 1908 inaugurated a new constitutional era in theOttoman Empire, unleashing hopes of a reinvigorated state committed to progressafter the decades of authoritarian Hamidian rule. While crowds of Ottomans ofdiverse backgrounds gathered in the streets to celebrate the dawn of a new era, foreignpowers had mixed reactions to the changes brought about by the revolution. Incontrast to the ambivalence of others, the official American reactions were unequivocallypositive. The Ottoman-American relationship had been relatively unimportantto both states, though Americans had significant interest in the Ottoman Empirethrough trade and missionary presence. The historiography of Ottoman-Americanrelations tends not to focus on the second constitutional period. However, the 1908Revolution witnessed a more significant transformation in the Ottoman-Americanrelationship than is often assumed. This thesis will analyze American diplomaticresponses to the 1908 Young Turk Revolution, arguing that the shared commitmentto constitutionalism emerging from the revolution opened up possibilities ofcooperation that had not existed before, as seen in the Ottoman student experienceColumbia University and especially that of Ahmet Emin (Yalman) . The cooperationof American and Ottoman embassies, Columbia University professors andadministration, and Ottoman students forged ties of trust and cooperation rootedin the possibilities of progress that could emerge from constitutional friendship