Olcay Gençyilmaz, İlker Kara, Ahmed Majeed Fadhil Alsamarai
In this study, we fabricated and analysed heterostructure thin films based on nickel oxide (NiO) films using the low-cost successive ionic layer adsorption and reaction (SILAR) method. NiO films were deposited on three substrates: indium tin oxide (ITO), fluorine tin oxide (FTO) and glass. The structural, optical, electrical and surface properties of the NiO films were investigated, revealing that all films have a cubic crystal structure with grain sizes varying between 30-60 nm. The optical energy range of the films was determined to be between 3.56-4 eV by analysing their optical properties. Furthermore, it was observed that the use of ITO base in Ag/p-NiO/n-ITO/Ag heterostructure thin films significantly increased their transmittance values to approximately 40%. The I-V characteristics of Ag/p-NiO/n-ITO/Ag, Ag/p-NiO/n-FTO/Ag and Ag/p-NiO/Glass/Ag heterostructures were examined. The maximum barrier height (ΦB) for the Ag/p-NiO/n-ITO/Ag heterostructure thin film was found to be 0.55 eV. In addition, the minimum ideality factor for this film was obtained to be 1.44 eV. The I-V analysis revealed that the Ag/p-NiO/n-ITO/Ag heterostructure is particularly suitable as a photoanode for solar cell applications.
In this article we complete the work started in arXiv:2303.00376v1 [math.AG] and arXiv:2404.18808v1 [math.AG], explicitly determining the Weierstrass semigroup at any place and the full automorphism group of a known $\mathbb{F}_{q^2}$-maximal function field $Z_3$ having the third largest genus, for $q \equiv 0 \pmod 3$. The cases $q \equiv 2 \pmod 3$ and $q \equiv 1 \pmod 3$ have been in fact analyzed in arXiv:2303.00376v1 [math.AG] and arXiv:2404.18808v1 [math.AG], respectively. As in the other two cases, the function field $Z_3$ arises as a Galois subfield of the Hermitian function field, and its uniqueness (with respect to the value of its genus) is a well-known open problem. Knowing the Weierstrass semigroups may provide a key towards solving this problem. Surprisingly enough, $Z_3$ has many different types of Weierstrass semigroups and the set of its Weierstrass places is much richer than its set of $\mathbb{F}_{q^2}$-rational places. We show that a similar exceptional behaviour does not occur in terms of automorphisms, that is, $\mathrm{Aut}(Z_3)$ is exactly the automorphism group inherited from the Hermitian function field, apart from the case $q=3$.
Andrea L Rosso, Zachary A Marcum, Xiaonan Zhu
et al.
Abstract Background Anticholinergic medications are associated with fall risk. Higher dopaminergic signaling may provide resilience to these effects. We tested interactions between anticholinergic medication use and dopaminergic genotype on risk for recurrent falls over 10 years. Methods Participants in the Health, Aging, and Body Composition (Health ABC) study (n = 2 372, mean age = 73.6; 47.8% men; 60.0% White) without disability or anticholinergic use at baseline were followed for up to 10 years for falls. Medication use was documented in 7 of 10 years. Highly anticholinergic medications were defined by Beers criteria, 2019. Recurrent falls were defined as ≥2 in the 12 months following medication assessment. Generalized estimating equations tested the association of anticholinergic use with recurrent falls in the following 12 months, adjusted for demographics, health characteristics, and anticholinergic use indicators. Effect modification by dopaminergic genotype (catechol-O-methyltransferase [COMT]; Met/Met, higher dopamine signaling, n = 454 vs Val carriers, lower dopamine signaling, n = 1 918) was tested and analyses repeated stratified by genotype. Results During follow-up, 841 people reported recurrent falls. Anticholinergic use doubled the odds of recurrent falls (adjusted odds ratio [OR] [95% CI] = 2.09 [1.45, 3.03]), with suggested effect modification by COMT (p = .1). The association was present in Val carriers (adjusted OR [95% CI] = 2.16 [1.44, 3.23]), but not in Met/Met genotype (adjusted OR [95% CI] = 1.70 [0.66, 4.41]). Effect sizes were stronger when excluding baseline recurrent fallers. Conclusion Higher dopaminergic signaling may provide protection against increased 12-month fall risk from anticholinergic use. Assessing vulnerability to the adverse effects of anticholinergic medications could help in determination of risk/benefit ratio for prescribing and deprescribing anticholinergics in older adults.
Arguably, the first bridge between vast, ancient, but disjoint domains of mathematical knowledge, – topology and number theory, – was built only during the last fifty years. This bridge is the theory of spectra in the stable homotopy theory. In particular, it connects Z, the initial object in the theory of commutative rings, with the sphere spectrum S: see [Sc01] for one of versions of it. This connection poses the challenge: discover a new information in number theory using the developed independently machinery of homotopy theory. (Notice that a passage in reverse direction has already generated results about computability in the homotopy theory: see [FMa20] and references therein.) In this combined research/survey paper we suggest to apply homotopy spectra to the problem of distribution of rational points upon algebraic manifolds. Subjects: Algebraic Geometry (math.AG); Number Theory (math.NT); Topology (math.AT) Comments: 72 pages. MSC-classes: 16E35, 11G50, 14G40, 55P43, 16E20, 18F30. CONTENTS 0. Introduction and summary 1. Homotopy spectra: a brief presentation 2. Diophantine equations: distribution of rational points on algebraic varieties 3. Rational points, sieves, and assemblers 4. Anticanonical heights and points count 5. Sieves “beyond heights” ? 6. Obstructions and sieves 7. Assemblers and spectra for Grothendieck rings with exponentials References 1
<p>Networks of nanomaterials sit at a confluence of desirable features for the fabrication of advanced electronic devices, including facile fabrication, high conducting element density, and novel electrical characteristics. The spatial conduction through carbon nanotube (CNT) and Ag-Ag₂S-Ag atomic switch networks was investigated to determine how better to implement them in novel sensing and computation device platforms. Selective gating of localized regions of CNT networks with varying densities was investigated. To achieve this, lithographically defined FET structures were developed that allowed gating of localised regions of the CNT FET network area. The CNT FET device sensitivity to gating of different regions of the CNT network was measured for devices with network densities close to the percolation threshold. A 10² increase in sensitivity to local gating for CNT FET devices with low network densities was observed compared with high-density CNT networks. Networks densities were all well below a density where metallic shorts could be present, so the trends observed were attributed to m-s junction dominated gating of the network. A better understanding of the dominant conduction in CNT network FETs at low network densities is important for tuning their properties for use as novel biosensing platforms or a tunable connectivity conducting film. A CNT network simulation was developed to test the effects of local gating on networks of bundled CNTs with varying densities. Up to 70,000 bundles on a 60 µm x 60 µm simulated network area were used to generate an electrical network of field sensitive elements where the gate field could be spatially modified to investigate the effect of local gating. Monte Carlo methods were used to simulate large numbers of random networks with m-s junctions as the dominant gate-dependent element. Networks with 13.5% metallic bundles were shown to exhibit trends in local gating similar to the experimental systems. Current density maps showed key conduction paths in low-density devices, which supports a model of m-s junction dominance to explain the local and global gate responses measured in experimental CNT FET systems. Prototype Ag-Ag₂S-Ag atomic switch networks (ASN) device were fabricated using spray-coated silver nanowires which were sulfurised using gas-phase sulfur after deposition. Electrical formation of memristive junctions and hysteretic switching curves were shown under swept voltage bias demonstrating memristive behaviour. ASN devices have been demonstrated to show critical dynamics and memristive characteristics due to the complex connection of atomic switches formed at Ag-Ag₂S-Ag junctions between wires. A fabrication and measurement protocol for ASN based neuromorphic devices on multi-electrode array (MEA) platforms was developed. The electrical measurement system was designed and deployed to facilitate time-resolved measurement across multiple channels simultaneously on those MEA platforms. Under DC bias, MEA-based ASN devices showed switching events with a power-law distribution over two orders of magnitude of conductance changes and time intervals consistent with self-organized criticality within the network. The dynamic response of the critical system was measured across the network area. Changes in the relative voltage across the ASN network area were observed using 16 channel MEA platforms, showing spatiotemporal variation in voltage across the network. Novel application of principal component analysis to ASNswas used to demonstrate reduction of dimension while preserving relative voltage changes. This paves the way for scalable analysis of the complex dynamic signals from critical ASN systems.</p>
It was known through the efforts of many works that the generating functions in the closed Gromov–Witten theory of $$K_{{\mathbb {P}}^2}$$KP2 are meromorphic quasi-modular forms (Coates and Iritani in Kyoto J Math 58(4):695–864, 2018; Lho and Pandharipande in Adv Math 332:349–402, 2018; Coates and Iritani in Gromov–Witten invariants of local $${\mathbb {P}}^{2}$$P2 and modular forms, arXiv:1804.03292 [math.AG], 2018) basing on the B-model predictions (Bershadsky et al. in Commun Math Phys 165:311–428, 1994; Aganagic et al. in Commun Math Phys 277:771–819, 2008; Alim et al. in Adv Theor Math Phys 18(2):401–467, 2014). In this article, we extend the modularity phenomenon to $$K_{{{\mathbb {P}}^1}\times {{\mathbb {P}}^1}}, K_{W{\mathbb {P}}[1,1,2]}, K_{{\mathbb {F}}_1}$$KP1×P1,KWP[1,1,2],KF1. More importantly, we generalize it to the generating functions in the open Gromov–Witten theory using the theory of Jacobi forms where the open Gromov–Witten parameters are transformed into elliptic variables.
We classify non-smooth del Pezzo surfaces with $$\frac{1}{3}(1,1)$$13(1,1) points in 29 qG-deformation families grouped into six unprojection cascades (this overlaps with work of Fujita and Yasutake in Classification of log del Pezzo surfaces of index three, arXiv:1401.1283 [math.AG]), we tabulate their biregular invariants, we give good model constructions for surfaces in all families as degeneracy loci in rep quotient varieties, and we prove that precisely 26 families admit qG-degenerations to toric surfaces. This work is part of a program to study mirror symmetry for orbifold del Pezzo surfaces (Akhtar et al. in Proc Am Math Soc 144(2):513–527, 2016).
We prove that every simplicial complex is the dual complex of some simple normal crossing divisor in a smooth variety. As an application, we simplify and extend the results of Kapovich--Kollár (math.AG:1109.4047) on the existence of singularities with given dual complex.
Abstract An abelian cover is a finite morphism X→Y of varieties which is the quotient map for a generically faithful action of a finite abelian group G. Abelian covers with Y smooth and X normal were studied in [R. Pardini, Abelian covers of algebraic varieties, J. Reine Angew. Math. 417 (1991), 191–213; MR 1103912(92g:14012)]. Here we study the non-normal case, assuming that X and Y are S2 varieties that have at worst normal crossings outside a subset of codimension greater than or equal to two. Special attention is paid to the case of ℤr2-covers of surfaces, which is used in [V. Alexeev and R. Pardini, Explicit compactifications of moduli spaces of Campedelli and Burniat surfaces, Preprint (2009), math.AG/arXiv:0901.4431] to construct explicitly compactifications of some components of the moduli space of surfaces of general type.
Elsa S. Strotmeyer, Aruna Kamineni, Jane A. Cauley
et al.
Type 2 diabetes is associated with higher fracture risk. Diabetes-related conditions may account for this risk. Cardiovascular Health Study participants (N=5641; 42.0% men; 15.5% black; 72.8±5.6 years) were followed 10.9±4.6 years. Diabetes was defined as hypoglycemic medication use or fasting glucose (FG)≥126 mg/dL. Peripheral artery disease (PAD) was defined as ankle-arm index <0.9. Incident hip fractures were from medical records. Crude hip fracture rates (/1000 person-years) were higher for diabetic vs. non-diabetic participants with BMI <25 (13.6, 95% CI: 8.9–20.2 versus 11.4, 95% CI: 10.1–12.9) and BMI≥25 to <30 (8.3, 95% CI: 5.7–11.9 versus 6.6, 95% CI: 5.6–7.7), but similar for BMI≥30. Adjusting for BMI, sex, race, and age, diabetes was related to fractures (HR = 1.34; 95% CI: 1.01–1.78). PAD (HR = 1.25 (95% CI: 0.92–1.57)) and longer walk time (HR = 1.07 (95% CI: 1.04–1.10)) modified the fracture risk in diabetes (HR = 1.17 (95% CI: 0.87–1.57)). Diabetes was associated with higher hip fracture risk after adjusting for BMI though this association was modified by diabetes-related conditions.
In math.AG/0207233, Okounkov and Pandharipande gave an operator formalism for computing the equivariant Gromov-Witten theory of the projective line. This thesis extends their result to orbifold lines. In the effective case the theory is again governed by the 2-Toda hierarchy. In the ineffective case the decomposition conjecture of hep-th/0606034 is verified.
We compute, with symplectic field theory (SFT) techniques, the Gromov-Witten theory of $${\mathbb{P}^1_{\alpha_1,\ldots,\alpha_a}}$$, i.e., the complex projective line with a orbifold points. A natural subclass of these orbifolds, the ones with polynomial quantum cohomology, gives rise to a family of (polynomial) Frobenius manifolds and integrable systems of Hamiltonian PDEs, which extend the (dispersionless) bigraded Toda hierarchy (Carlet, The extended bigraded toda hierarchy. arXiv preprint arXiv:math-ph/0604024). We then define a Frobenius structure on the spaces of polynomials in three complex variables of the form F(x, y, z) = −xyz + P1(x) + P2(y) + P3(z) which contains as special cases the ones constructed on the space of Laurent polynomials (Dubrovin, Geometry of 2D topologica field theories. Integrable systems and quantum groups, Springer Lecture Notes in Mathematics 1620:120–348, 1996; Milanov and Tseng, The space of Laurent polynomials, $${\mathbb{P}^1}$$-orbifolds, and integrable hierarchies. preprint arXiv:math/0607012v3 [math.AG]). We prove a mirror theorem stating that these Frobenius structures are isomorphic to the ones found before for polynomial $${\mathbb{P}^1}$$-orbifolds. Finally we link rational SFT of Seifert fibrations over $${\mathbb{P}^1_{a,b,c}}$$ with orbifold Gromov-Witten invariants of the base, extending a known result (Bourgeois, A Morse-Bott approach to contact homology. Ph.D. dissertation, Stanford University, 2002) valid in the smooth case.
This is an extended example of the study of mirror symmetry via log schemes and the discrete Legendre transform on affine manifolds, introduced by myself and Bernd Siebert in "Mirror Symmetry via Logarithmic Degeneration Data I" (math.AG/0309070). In this paper, I consider the construction as it applies to the Batyrev-Borisov construction for complete intersections in toric varieties. Given a pair of reflexive polytopes with nef decompositions dual to each other, and given polarizations on the corresponding toric varieties, we construct examples of toric degenerations and their dual intersection complexes, which are affine manifolds with singularities. We show these affine manifolds are related by the discrete Legendre transform, thus showing that the Batyrev-Borisov construction is a special case of our more general construction. The description of the dual intersection complexes in terms of the combinatoricsof the setup generalises work of Haase and Zharkov in the toric hypersurface case, and similar work of Ruan. In particular, this gives a topological description of the Strominger-Yau-Zaslow fibrations on complete intersections in toric varieties.
We construct the derived version of the Hilbert scheme parametrizing subschemes in a given projective scheme X with given Hilbert polynomial h. This is a dg-manifold (smooth dg-scheme) RHilb_h(X) which carries a natural family of commutative (up to homotopy) dg-algebras, which over the usual Hilbert scheme is just given by truncations of the homogeneous coordinate rings of subschemes in X. In particular, RHilb_h(X) differs from RQuot_h(O_X), the derived Quot scheme constructed in our previous paper (math.AG/9905174) which carries only a family of A-infinity modules over the coordinate algebra of X. As an application, we construct the derived version of the moduli stack of stable maps of (variable) algebraic curves to a given projective variety Y, thus realizing the original suggestion of M. Kontsevich.
We study the Toda conjecture of Eguchi and Yang for the Gromov-Witten invariants of CP^1,using the bihamiltonian method of the formal calculus of variations. We also study its relationship to the Virasoro conjecture for CP^1, recently proved by Givental (math.AG/0108100).