Birth and Death of Chimera: Interplay of Delay and Multiplexing

The chimera state with co-existing coherent-incoherent dynamics has recently attracted a lot of attention due to its wide applicability. We investigate non-locally coupled identical chaotic maps with delayed interactions in the multiplex network framework and find that an interplay of delay and multiplexing brings about an enhanced or suppressed appearance of chimera state depending on the distribution as well as the parity of delay values in the layers. Additionally, we report a layer chimera state with an existence of one layer displaying coherent and another layer demonstrating incoherent dynamical evolution. The rich variety of dynamical behavior demonstrated here can be used to gain further insight into the real-world networks which inherently possess such multi-layer architecture with delayed interactions

Explosive synchronization in interlayer phase-shifted Kuramoto oscillators on multiplex networks

We show that an introduction of a phase parameter ($\alpha$), with $0 \le \alpha \le \pi/2$, in the interlayer coupling terms of multiplex networks of Kuramoto oscillators can induce explosive synchronization (ES) in the multiplexed layers. Along with the {\alpha} values, the hysteresis width is determined by the interlayer coupling strength and the frequency mismatch between the mirror (inter-connected) nodes. A mean-field analysis is performed to support the numerical results. Similar to the earlier works, we find that the suppression of synchronization is accountable for the origin of ES. The robustness of ES against changes in the network topology and frequency distribution is tested. Finally, taking a suggestion from the synchronized state of the multiplex networks, we extend the results to the classical concept of the single-layer networks in which some specific links are assigned a phase-shifted coupling. Different methods have been introduced in the past years to incite ES in coupled oscillators; our results indicate that a phase-shifted coupling can also be one such method to achieve ES.Comment: 9 pages, 8 figure

Mirror node correlations tuning synchronization in multiplex networks

Peer reviewedPublisher PD

Metabolic studies in genomic era

Introduction: There are about 1450 Inborn Metabolic Disorders listed in the International Classification of Inherited Metabolic Disorders. The outcome in these disorders depends on the early diagnosis and prompt treatment. However, the diagnosis of these disorders is very complex due to the vast diversity in presentation. With advancement of science and technology, the genomic studies have become easily available and less costly. However, the biochemical studies still have a very important part to play in the early diagnosis of these disorders as well as treatment monitoring. Genomic era has opened many doors of opportunity for improved diagnosis, appropriate and rational treatment, and good follow-up. Aims and Objectives: To understand the relevance and usefulness of metabolic or biochemical tests for identification on inborn errors of metabolism in the genomic era. Materials and Methods: Published literature in English was searched on PubMed using the keywords metabolic studies, new-born screening (NBS), biomarkers, metabolomics, and inborn errors of metabolism. We selected 10 such publications to understand the relevance of biochemical or metabolic studies in the current genomic era. Results and Discussion: Since there is no experimental data or statistics involved here, we will discuss the application of metabolic tests or metabolomics in the current era. Conclusion: Biochemical studies are important for NBS or family screening, diagnostic testing, biomarkers, testing for follow-up of treatment, and prognostication purposes and metabolomics. A combined biochemical and genetic testing approach helps in increasing the diagnostic yield, and hence, it is important to examine a patient clinically and then plan investigations to save time and resources

Supplemental Material: Non-Identical Multiplexing promotes chimera states

We present the emergence of chimeras, a state referring to coexistence of partly coherent, partly<br>incoherent dynamics in networks of identical oscillators, in a multiplex network consisting of two<br>non-identical layers which are interconnected. We demonstrate that the parameter range displaying<br>the chimera state in the homogeneous first layer of the multiplex networks can be tuned by changing<br>the link density or connection architecture of the same nodes in the second layer. We focus on the<br>impact of the interconnected second layer on the enlargement or shrinking of the coupling regime for<br>which chimeras are displayed in the homogeneous first layer. We find that a denser homogeneous<br>second layer promotes chimera in a sparse first layer, where chimeras do not occur in isolation.<br>Furthermore, while a dense connection density is required for the second layer if it is homogeneous,<br>this is not true if the second layer is inhomogeneous. We demonstrate that a sparse inhomogeneous<br>second layer which is common in real-world complex systems, can promote chimera states in a sparse<br>homogeneous first layer

Urea cycle disorders in India: clinical course, biochemical and genetic investigations, and prenatal testing

Abstract Background Urea cycle disorders (UCDs) are inherited metabolic disorders that present with hyperammonemia, and cause significant mortality and morbidity in infants and children. These disorders are not well reported in the Indian population, due to lack of a thorough study of the clinical and molecular profile. Results We present data from two major metabolic centres in India, including 123 cases of various UCDs. The majority of them (72/123, 58%) presented in the neonatal period (before 30 days of age) with 88% on or before day 7 of life (classical presentation), and had a high mortality (64/72, 88%). Citrullinemia type 1 was the most common UCD, observed in 61/123 patients. Ornithine transcarbamylase (OTC) deficiency was the next most common, seen in 24 cases. Argininosuccinic aciduria was diagnosed in 20 cases. Deficiencies of arginase, N-acetylglutamate synthase, carbamoyl phosphate synthetase, citrin, and lysinuric protein intolerance were also observed. Molecular genetic analysis revealed two common ASS1 mutations: c.470G > A (p.Arg157His) and c.1168G > A (p.Gly390Arg) (36 of 55 tested patients). In addition, few recurrent point mutations in ASL gene, and a deletion of the whole OTC gene were also noted. A total of 24 novel mutations were observed in the various genes studied. We observed a poor clinical outcome with an overall all time mortality of 63% (70/110 cases with a known follow-up), and disability in 70% (28/40) among the survivors. Prenatal diagnosis was performed in 30 pregnancies in 25 families, including one pre-implantation genetic diagnosis. Conclusions We report the occurrence of UCDs in India and the spectrum that may be different from the rest of the world. Citrullinemia type 1 was the most common UCD observed in the cohort. Increasing awareness amongst clinicians will improve outcomes through early diagnosis and timely treatment. Genetic diagnosis in the proband will enable prenatal/pre-implantation diagnosis in subsequent pregnancies