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Design and development of robust and precision personalized medicine
No full textFrederike H. Petzschner recently published an article in Science titled ‘Practical challenges for precision medicine’ (Science, 2024, 383, 149–150; doi:10.1126/science.adm9218) expressing the view that machine learning tools are not suitable for advancing precision medicine. In this write-up, we present some evidences which show that mathematical genomics, mathematical proteomics, statistical genomics and statistical proteomics, along with machine learning tools can effectively guide the development of high-precision personalized medicine
Design and fabrication of internal mixer and filament extruder for extraction of hybrid filament composite for FDM applications
No full textAdditive manufacturing is an advanced manufacturing technology to produce components with superior quality, aesthetic shape, less wastage and reduced production time. Fused deposition modeling (FDM) is one of the additive manufacturing techniques adopted by small scale industries as it is most economical and produces compact sized components. Even though, the lack of feedstock (i.e., filament) material leads to increase in overall manufacturing cost. This paper explores design and fabrication of internal mixer (IM) and filament extruder for blending of composite materials, production of polymer filaments and hybrid composite filaments (i.e., polymer filaments with reinforcement of natural fibers) for FDM applications. The polylactic acid polymer, bamboo natural fibers and maleic anhydride compatibilizer are taken as a raw material. The internal mixer has been fabricated successfully is the most economical approach as compared to commercially available IM. The result shows that, the developed IM produces 250 g of blended mixture (i.e., combination of polymers, natural fibers and plasticizers) in a duration of 30 min. Also, the designed and fabricated portable filament extruder tested and extracted continuous polymer and hybrid filaments with a diameter ranging from 1.6 to 2 mm and mass flow rate of 15.6 mm3/s respectively. In addition, the obtained filament having no warping, without clogging, no under and over extrusion, more precise and most economical as compared to existing filament extruders. The developed IM and filament extruder are adequate to small scale vendors and industries
Determinants vs. Algebraic Branching Programs
No full textWe show that, for every homogeneous polynomial of degree d, if it has determinantal complexity at most s, then it can be computed by a homogeneous algebraic branching program (ABP) of size at most O(d5s). Moreover, we show that for most homogeneous polynomials, the width of the resulting homogeneous ABP is just s-1 and the size is at most O(ds). Thus, for constant-degree homogeneous polynomials, their determinantal complexity and ABP complexity are within a constant factor of each other and hence, a super-linear lower bound for ABPs for any constant-degree polynomial implies a super-linear lower bound on determinantal complexity; this relates two open problems of great interest in algebraic complexity. As of now, super-linear lower bounds for ABPs are known only for polynomials of growing degree (Chatterjee et al. 2022; Kumar2019), and for determinantal complexity the best lower bounds are larger than the number of variables only by a constant factor (Kumar& Volk 2022). While determinantal complexity and ABP complexity are classically known to be polynomially equivalent (Mahajan & Vinay 1997), the standard transformation from the former to the latter incurs a polynomial blow up in size in the process, and thus, it was unclear if a super-linear lower bound for ABPs implies a super-linear lower bound on determinantal complexity. In particular, a size preserving transformation from determinantal complexity to ABPs does not appear to have been known prior to this work, even for constant-degree polynomials
Directional synchrony among self-propelled particles under spatial influence
No full textSynchronization is one of the emerging collective phenomena in interacting particle systems. Its ubiquitous presence in nature, science, and technology has fascinated the scientific community over the decades. Moreover, a great deal of research has been, and is still being, devoted to understand various physical aspects of the subject. In particular, the study of interacting active particles has led to exotic phase transitions in such systems which have opened up a new research front-line. Motivated by this line of work, in this paper, we study the directional synchrony among self-propelled particles. These particles move inside a bounded region, and crucially their directions are also coupled with spatial degrees of freedom. We assume that the directional coupling between two particles is influenced by the relative spatial distance which changes over time. Furthermore, the nature of the influence is considered to be both short and long-ranged. We explore the phase transition scenario in both the cases and propose an approximation technique which enables us to analytically find the critical transition point. The results are further supported with numerical simulations. Our results have potential importance in the study of active systems like bird flocks, fish schools, and swarming robots where spatial influence plays a pertinent role
Dyke emplacement under mixed loading conditions: Insights from the Dharwar Craton, India
No full textDykes are intrusive igneous bodies that play crucial role in the supply and ascent of magma to the Earth\u27s crust. Magma can intrude along pre-existing anisotropies such as fractures or foliations present within the host rock or it may create its own path by fracturing the host rock. In the latter scenario, when fractures are formed by the pressure exerted by the invading magma, a dyke\u27s outcrop shape and geometry are diagnostic of the conditions under which it evolved. Here, we report mafic dykes emplaced within the younger granites of Dharwar Craton, peninsular India. Outcrop attributes of these dykes are characteristic of emplacement under conditions of mixed mode loading. We discuss different discrete modes of fracture formation and their possible combinations to understand the generation and eventual emplacement of dykes under mixed mode loading. This leads to the development of a comprehensive sequence of progressive dyke evolution under mixed mode I-III loading and thereby distinguishing incremental orders of dyke horn formation. We further apply this knowledge along with collected field evidence on dyke body geometries to propose an evolutionary model of dyke formation and emplacement within the Chitradurga granite under varying regional stress fields of the Chitradurga Schist Belt, Western Dharwar Craton, India. We infer, that the dykes initiated as extensional fractures within an earlier NE-SW directed compressive stress field and were subsequently sheared sinistrally by the effect of the adjacent Chitradurga Shear Zone on account of a later E-W to ESE-WNW directed compression
Electoral competition, electoral uncertainty and corruption: Theory and evidence from India
No full textIn this paper we study the effect of electoral competition on corruption when uncertainty in elections is high, as is the case in many developing countries. Our theory shows that in such a context high levels of electoral competition may have perverse effects on corruption. We illustrate the predictions of the model with village level data on audit-detected irregularities and electoral competition from India. Our results imply that accountability can be weak in such contexts, despite high electoral competition
ENLIGHTENMENT: A Scalable Annotated Database of Genomics and NGS-Based Nucleotide Level Profiles
No full textThe revolution in sequencing technologies has enabled human genomes to be sequenced at a very low cost and time leading to exponential growth in the availability of whole-genome sequences. However, the complete understanding of our genome and its association with cancer is a far way to go. Researchers are striving hard to detect new variants and find their association with diseases, which further gives rise to the need for aggregation of this Big Data into a common standard scalable platform. In this work, a database named Enlightenment has been implemented which makes the availability of genomic data integrated from eight public databases, and DNA sequencing profiles of H. sapiens in a single platform. Annotated results with respect to cancer specific biomarkers, pharmacogenetic biomarkers and its association with variability in drug response, and DNA profiles along with novel copy number variants are computed and stored, which are accessible through a web interface. In order to overcome the challenge of storage and processing of NGS technology-based whole-genome DNA sequences, Enlightenment has been extended and deployed to a flexible and horizontally scalable database HBase, which is distributed over a hadoop cluster, which would enable the integration of other omics data into the database for enlightening the path towards eradication of cancer
Evaluating Tensile Fractures in Rigid Clasts with Very High Aspect Ratio
No full textAbstract: We investigate how a highly elliptical and mechanically rigid clast embedded in an infinite rock mass respond to the far-field stresses. The numerical analysis is carried out on elliptical clasts with aspect ratios ranging from 13.5 to 58.5, oriented at a right angle to the maximum far-field stress. A 2D plane strain model has been adopted to decipher the states of stress inside elliptical clasts. We argue that the tensile stress within the clasts gets enhanced and develops systematic mode-I (tensile) fractures within it as the far-field stress increases. We conclude that the intra-clast tensile stress decreases with increasing clast ellipticity, i.e., tensile fractures develop more easily within clasts with higher aspect ratios (~\u3e20) while a higher far field tensile stress is required to fracture clasts with lower aspect ratios. We also interpret that stress enhancement is independent of the clast area and inter-focii distance of the clast, whilst the aspect ratio of the clast is found to be crucial for the development of tensile fractures within the elliptical clast for a constant material property
Examining the Factors That Facilitate or Hinder the Use of Blockchain Technology to Enhance the Resilience of Supply Chains
No full textThe integration of global supply chains allows for exchanging innovative ideas, knowledge, crafts, and technology across borders. However, it also poses a significant risk of experiencing irregular disruptions. To address these concerns, resilient systems require innovative technology-based solutions, such as blockchain. This comprehensive study involved conducting a systematic literature review and utilizing qualitative input-based decision-making trial and evaluation laboratory (methodology to identify the key enablers and barriers for blockchain-enabled resilient supply chains. A total of 11 enablers and 12 barriers were identified. A panel of 15 experts from various backgrounds was utilized to provide the input through the online instrument. Based on the results, transparency followed by trust and collaboration as the top three crucial enablers, and lack of acceptance in the industry, complexity, and lack of standardization as the top three crucial barriers for blockchain-enabled resilient supply chain. The study also identified shared databases, smart contracts, and real-time information as key causal enablers and lack of standardization, complexity, and government support as key causal barriers for blockchain enabled resilient supply chain. This study further suggests practitioners and policymakers to prioritize promoting the adoption of blockchain technology (BT) to ensure the resilience of supply chains by launching awareness programs, conducting world-class training of employees, and implementing blockchain favoring policies. The study further provides a critical insight suggesting that the pillars that promote blockchain adoption inherently favor the resilience strategies/pillars (visibility, collaboration, traceability, risk management, security and real-time data sharing) and hence, indicates that adoption of BT would implicitly enhance resilience. The study concludes with limitations, future research directions and conclusion
Expected polynomial-time randomized algorithm for graph coloring problem
No full textGiven a graph G=(V,E) with n=|V| vertices, the graph coloring problem is defined as Find a color vector C=(c(v)), where c(v)∈{1,2,…,n} denotes the color of vertex v∈V, such that no monochromatic edge exists in G and the span, the total number of distinct colors in C, is minimized. Since the problem is NP-complete, a greedy coloring is commonly used for solving it. Greedy coloring visits the vertices of G following an order S, and while visiting a vertex v, it puts the minimum color absent in all neighbors of v. We show that the orders producing span ≤k, where k≤n is a positive integer, can be partitioned into disjoint subsets of equivalent orders. Next, we propose a selective search (SS) algorithm, which takes ρ as an input parameter, selects ≥ρ orders each from a different set of equivalent orders with high probability, applies greedy coloring on them, and returns the color vector with minimum span. We analytically show that SS performs better than greedy coloring with high probability by evaluating the same number of orders. We propose an incremental search heuristic (ISH), which ρ1 times execute SS with parameter ρ2 and returns the color vector with minimum span. A parallel version of ISH called PISH is also proposed, executing ρ1 SS calls in parallel. We show that ISH hits an optimum coloring for a graph G=(V,E) with χ(G)(Δ(G)+1)≤[Formula presented.] in expected O(|V|+|E|) time and space complexities. We have evaluated ISH and PISH on 136 challenging benchmarks and shown that they significantly outperform 10 existing state-of-the-art algorithms. Finally, we validated our theoretical findings by evaluating ISH and greedy coloring on random graphs