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A bstract We study the topological properties of Calabi-Yau threefold hypersurfaces at large h 1 , 1 . We obtain two million threefolds X by triangulating polytopes from the Kreuzer-Skarke list, including all polytopes with 240 ≤ h 1 , 1 ≤ 491. We show that the Kähler cone of X is very narrow at large h 1 , 1 , and as a consequence, control of the α′ expansion in string compactifications on X is correlated with the presence of ultralight axions. If every effective curve has volume ≥ 1 in string units, then the typical volumes of irreducible effective curves and divisors, and of X itself, scale as ( h 1 , 1 ) p , with 3 ≲ p ≲ 7 depending on the type of cycle in question. Instantons from branes wrapping these cycles are thus highly suppressed.

A bstract We construct supersymmetric AdS 4 vacua of type IIB string theory in compactifications on orientifolds of Calabi-Yau threefold hypersurfaces. We first find explicit orientifolds and quantized fluxes for which the superpotential takes the form proposed by Kachru, Kallosh, Linde, and Trivedi. Given very mild assumptions on the numerical values of the Pfaffians, these compactifications admit vacua in which all moduli are stabilized at weak string coupling. By computing high-degree Gopakumar-Vafa invariants we give strong evidence that the α ′ expansion is likewise well-controlled. We find extremely small cosmological constants, with magnitude < 10 − 123 in Planck units. The compactifications are large, but not exponentially so, and hence these vacua manifest hierarchical scale-separation, with the AdS length exceeding the Kaluza-Klein length by a factor of a googol.

A bstract We show that the strong CP problem is solved in a large class of compactifications of string theory. The Peccei-Quinn mechanism solves the strong CP problem if the CP-breaking effects of the ultraviolet completion of gravity and of QCD are small compared to the CP-preserving axion potential generated by low-energy QCD instantons. We characterize both classes of effects. To understand quantum gravitational effects, we consider an ensemble of flux compactifications of type IIB string theory on orientifolds of Calabi-Yau hypersurfaces in the geometric regime, taking a simple model of QCD on D7-branes. We show that the D-brane instanton contribution to the neutron electric dipole moment falls exponentially in N 4 , with N the number of axions. In particular, this contribution is negligible in all models in our ensemble with N > 17. We interpret this result as a consequence of large N effects in the geometry that create hierarchies in instanton actions and also suppress the ultraviolet cutoff. We also compute the CP breaking due to high-energy instantons in QCD. In the absence of vectorlike pairs, we find contributions to the neutron electric dipole moment that are not excluded, but that could be accessible to future experiments if the scale of supersymmetry breaking is sufficiently low. The existence of vectorlike pairs can lead to a larger dipole moment. Finally, we show that a significant fraction of models are allowed by standard cosmological and astrophysical constraints.

In the realm of digital image security, the multiple-image encryption (MIE) has garnered increasing attention due to the prevalent dissemination of digital imagery. Responding to this trend, an innovative encryption method has been developed, capable of securing an arbitrary number of images efficiently. This method is underpinned by the newly devised sine quadratic polynomial map (SQPM) and an original space-filling curve technique, termed U-shaped scanning. Extensive analysis, including 2D and 3D phase diagrams, Lyapunov exponents, bifurcation diagrams, and approximate entropy calculations, confirms the SQPM's chaotic properties over a broad spectrum of control parameters. The U-shaped scanning method, novel in its application, facilitates the traversal of every element in a 2D array, irrespective of its dimensions. This method is integral to the permutation phase of the encryption process, where it pre-scrambles input images, and it plays a pivotal role in the diffusion phase through the introduction of U-shaped diffusion. Comprehensive security assessments have been conducted, encompassing secret key analysis, histogram evaluation, correlation assessments, differential analysis, and information entropy measurements. Further scrutiny involves known-plaintext and chosen-plaintext attack resilience, along with visualizations of data loss and noise attack impacts, and execution time analysis across three sets of four images. The results of these security analyses affirm the efficacy of the proposed technique in encrypting multiple images, be they colored or grayscale. This work not only advances the field of image encryption but also introduces novel methodologies with broad applicability in digital image security.

A bstract We show that the Weak Gravity Conjecture (WGC) implies a nontrivial upper bound on the volumes of the minimal-volume cycles in certain homology classes that admit no calibrated representatives. In compactification of type IIB string theory on an orientifold X of a Calabi-Yau threefold, we consider a homology class [Σ] ∈ H 4 ( X, ℝ ) represented by a union Σ ∪ of holomorphic and antiholomorphic cycles. The instanton form of the WGC applied to the axion charge [Σ] implies an upper bound on the action of a non-BPS Euclidean D3-brane wrapping the minimal-volume representative Σ min of [Σ]. We give an explicit example of an orientifold X of a hypersurface in a toric variety, and a hyperplane H ⊂ H 4 ( X, ℝ ), such that for any [Σ] ∈ H that satisfies the WGC, the minimal volume obeys Vol (Σ min ) ≪ Vol(Σ ∪ ): the holomorphic and antiholomorphic components recombine to form a much smaller cycle. In particular, the sub-Lattice WGC applied to X implies large recombination, no matter how sparse the sublattice. Non-BPS instantons wrapping Σ min are then more important than would be predicted from a study of BPS instantons wrapping the separate components of Σ ∪ . Our analysis hinges on a novel computation of effective divisors in X that are not inherited from effective divisors of the toric variety.

A bstract We present an efficient algorithm for computing the prepotential in compactifications of type II string theory on mirror pairs of Calabi-Yau threefolds in toric varieties. Applying this method, we exhibit the first systematic computation of genus-zero Gopakumar-Vafa invariants in compact threefolds with many moduli, including examples with up to 491 vector multiplets.

Abstract Objective The aim of this study was to assess the oxidative stress (OS) levels and dynamic thiol-disulfide balance in preterm newborns with bronchopulmonary dysplasia (BPD). Methods This prospective study included newborns separated into 2 groups, those with BPD (case) or without BPD (control). The 2 groups were compared by clinical and laboratory findings. The OS parameters total oxidant status (TOS), total antioxidant status (TAS), OS index (OSI), native thiol (NT), and total thiol were measured within the first day after birth. Oxygen requirements were measured using the fraction of inspired oxygen (FIO2) recorded in the first hour after birth/admission and the average FIO2 within 28 days of the birth. Results Infants diagnosed with BPD had a significantly lower gestational age and birth weight and a lower 5-min Apgar score (P < .05). Infants with BPD also had a higher rate of respiratory distress syndrome, rate of use of surfactant therapy, duration of ventilation therapy, and duration of hospital stay compared with control (P = .001, P = .001, P = .001, and P = .001, respectively). Plasma TAS and NT levels of newborns with BPD were significantly lower than newborns without BPD (P < .05). In the BPD group, plasma TOS and OSI levels were significantly higher than in the control group. Conclusion We found that OS was increased in newborns with BPD. The clinical significance of this study will provide the clinician with a different perspective on BPD by determining the dynamic thiol disulfide balance.

Both the path integral measure in field theory (FT) and ensembles of neural networks (NN) describe distributions over functions. When the central limit theorem can be applied in the infinite-width (infinite- N ) limit, the ensemble of networks corresponds to a free FT. Although an expansion in 1 / N corresponds to interactions in the FT, others, such as in a small breaking of the statistical independence of network parameters, can also lead to interacting theories. These other expansions can be advantageous over the 1 / N -expansion, for example by improved behavior with respect to the universal approximation theorem. Given the connected correlators of a FT, one can systematically reconstruct the action order-by-order in the expansion parameter, using a new Feynman diagram prescription whose vertices are the connected correlators. This method is motivated by the Edgeworth expansion and allows one to derive actions for NN FT. Conversely, the correspondence allows one to engineer architectures realizing a given FT by representing action deformations as deformations of NN parameter densities. As an example, φ 4 theory is realized as an infinite- N NN FT.

This study presents design, performance analysis, and optimization of a hybrid microgrid for the hospital complex located on Eskişehir Osmangazi University (ESOGU) campus using Hybrid Optimization of Multiple Energy Resources (HOMER) software. Solar energy potential of the campus and the real electricity consumption of the hospital collected over one-year period were used in the design of the microgrid. The optimization takes into account the overall performance and the economic feasibility of the microgrid system over its lifetime. The designed microgrid consisting of photovoltaic (PV) modules, diesel generators, batteries, converters, and loads is configured as a grid-connected hybrid system. In order to optimize the system, PV module failures, increase in demand, increase in fuel cost of diesel generators, and mains interruptions are defined as performance variables and realistically modelled in the HOMER simulation. Later, both the individual and the combined effects of these variables on the performance of the microgrid was investigated via simulation using five operating scenarios. The objective was to obtain reliable data from the microgrid design that reflects the realistic operation of microgrid over its 25-years of service time. Simulation results have shown that the economic feasibility and the performance of the microgrid are greatly affected by these factors. For example, in a worst case scenario where all variables are acting together, net present cost increases to 40.44%, cost of energy increases to 21.92%, and operating cost rises to 53.91%. Moreover, the results show a reduction up to 33.30% in the portion of energy that is directly transferred from renewable sources to the load. The simulation results were then used to optimize the design of the microgrid system for the best overall performance. In conclusion, it was demonstrated that the proposed hybrid microgrid system supplies the energy demand of the hospital, lowers the cost of electricity consumption, provides a reasonable payback time, and the best of all, it contributes to the clean campus concept.©2019. CBIORE-IJRED. All rights reserved   Article History: Received May 16th 2018; Received in revised form October 18th 2018; Accepted December 16th 2018; Available onlineHow to Cite This Article: Çetinbaş, I., Tamyürek, B., and Demirtaş, M. (2019) Design, Analysis, and Optimization of a Hybrid Microgrid System Using HOMER Software: Eskişehir Osmangazi University Example. Int. Journal of Renewable Energy Development, 8(1), 65-79.https://doi.org/10.14710/ijred.8.1.65-79

Background Breath holding spells (BHS) are an important non-epileptic condition that is common in childhood and causes concern to families. YouTube is a powerful social media tool for accessing diseases and information such as BHS in child health. The aim of the study was to measure of the quality and reliability levels of the videos published in English on BHS uploaded on YouTube. Methods The key words “infant”, “cry”, “breath holding spells”, holding spells” and “breath spells” were searched on the YouTube on November 14, 2022, in this study. Along with the general features of the videos, their quality and reliability were evaluated according to the global quality score (GQS), mDISCERN score. Results Fifty-five videos were evaluated. The mDISCERN and GQS scores of the videos in the useful group were higher than those in the misleading group ( p  < 0.001, p  < 0.001). In the useful group, 87.5% of academic institutions and 93.3% of medical doctors (MDs) uploaded high-score GQS videos, while this rate was 16.7% in independent users ( p  = 0.005). The positive correlation was found between mDISCERN and GQS scores ( p  < 0.001). Conclusion The majority of YouTube videos on BHS contained useful information with sufficient quality. Professional associations such as universities and academic institutes need to produce better quality videos to provide families/users with more accurate and up-to-date information about BHS. We emphasize that YouTube should analyse videos published in the field of health, especially in the field of pediatrics, such as BHS, with committees consisting of expert health professionals, and publish them after evaluation. YouTube should consider collaborating with professional pediatrics health organizations such as American Academy of Pediatrics (AAP), academic institutes and universities in the field of BHS to produce high-quality videos.