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1. Evaluating LLMs' Mathematical Reasoning in Financial Document Question Answering

Author

Srivastava, Pragya, Malik, Manuj, Gupta, Vivek, Ganu, Tanuja, and Roth, Dan

Subjects
Computer Science - Computation and Language
Abstract

Large Language Models (LLMs), excel in natural language understanding, but their capability for complex mathematical reasoning with an amalgamation of structured tables and unstructured text is uncertain. This study explores LLMs' mathematical reasoning on four financial tabular question-answering datasets: TATQA, FinQA, ConvFinQA, and Multihiertt. Through extensive experiments with various models and prompting techniques, we assess how LLMs adapt to complex tables and mathematical tasks. We focus on sensitivity to table complexity and performance variations with an increasing number of arithmetic reasoning steps. The results provide insights into LLMs' capabilities and limitations in handling complex mathematical scenarios for semi-structured tables. Ultimately, we introduce a novel prompting technique tailored to semi-structured documents, matching or outperforming other baselines in performance while providing a nuanced understanding of LLMs abilities for such a task., Comment: 25 pages, 17 figures

Published
2024

2. NICE: To Optimize In-Context Examples or Not?

Author

Srivastava, Pragya, Golechha, Satvik, Deshpande, Amit, and Sharma, Amit

Subjects
Computer Science - Computation and Language, Computer Science - Artificial Intelligence, Computer Science - Machine Learning
Abstract

Recent work shows that in-context learning and optimization of in-context examples (ICE) can significantly improve the accuracy of large language models (LLMs) on a wide range of tasks, leading to an apparent consensus that ICE optimization is crucial for better performance. However, most of these studies assume a fixed or no instruction provided in the prompt. We challenge this consensus by investigating the necessity of optimizing ICE when task-specific instructions are provided and find that there are many tasks for which it yields diminishing returns. In particular, using a diverse set of tasks and a systematically created instruction set with gradually added details, we find that as the prompt instruction becomes more detailed, the returns on ICE optimization diminish. To characterize this behavior, we introduce a task-specific metric called Normalized Invariability to Choice of Examples (NICE) that quantifies the learnability of tasks from a given instruction, and provides a heuristic to help decide whether to optimize instructions or ICE for a new task. Given a task, the proposed metric can reliably predict the utility of optimizing ICE compared to using random ICE. Our code is available at https://github.com/microsoft/nice-icl., Comment: Accepted as a full paper (9 pages) at ACL 2024 (Main)

Published
2024

4. Towards Zero-Shot and Few-Shot Table Question Answering using GPT-3

Author

Srivastava, Pragya, Ganu, Tanuja, and Guha, Saikat

Subjects
Computer Science - Machine Learning, 14J60 (Primary)
Abstract

We present very early results on using GPT-3 to perform question answering on tabular data. We find that stock pre-trained GPT-3 is able to zero-shot learn the table structure from a serialized JSON array-of-arrays representation, and able to answer lookup queries and simple comparison questions in natural language without any fine-tuning. We further find that simple prompt engineering to include few-shot static Q&A examples significantly improves accuracy. Lastly, we find that intermixing passage text improves accuracy even further on heterogeneous data. We apply our approach on a novel dataset of simple tables in newspaper infographics with promising results. Overall, we find much cause for optimism in this basic approach., Comment: 7 pages

Published
2022

5. Mechanistic basis for PLK1-mediated regulation of centromere maintenance

Author

Srivastava, Pragya, Arulanandam, Arockia Jeyaprakash, and Heun, Patrick

Subjects
PLK1-mediated regulation, centromere maintenance, cell cycle, identical segregation of chromosomes, Equal segregation of chromosomes, accurate chromosome segregation, spindle microtubules, centromeric region of the chromosomes, eukaryotes, nucleosomes containing CENP-A, histone H3 variant, DNA replication-mediated dilution of CENP-A levels, CENP-A, binding of HJURP to the Mis18 complex
Abstract

Equal and identical segregation of chromosomes during each round of the cell cycle is essential for the faithful transmission of the genetic material. An important factor for accurate chromosome segregation is the stable attachment of spindle microtubules to the centromeric region of the chromosomes. In most eukaryotes, centromeres are epigenetically defined by the enrichment of nucleosomes containing CENP-A, a histone H3 variant. DNA replication-mediated dilution of CENP-A levels occurs as the existing CENP-A is distributed among the two DNA strands during the S-phase. In order to preserve centromere identity, CENP-A levels must be restored in a cell-cycle controlled manner. In humans, new CENP-A deposition occurs during the G1 phase and involves coordinated actions of several proteins. The Mis18 complex (Mis18a, Mis18b, Mis18BP1) is the central player in centromere maintenance that is recruited to the centromeres by CENP-C. Once the Mis18 complex localizes to the centromere, it recruits CENP-A-specific chaperone HJURP to deposit new CENP-A nucleosomes. PLK1 has been reported to promote new CENP-A deposition by phosphorylating Mis18BP1 and co-localizing with the Mis18 complex to the centromeres, but the precise mechanism determining its role in the maintenance of centromere identity is yet to be determined. In this study, I demonstrate that PLK1 interacts with the Mis18 complex via Mis18a and Mis18BP1 subunits in a phosphorylation-dependent manner via selfprimed phosphorylations. Mass spectrometry and biochemical assays were used to narrow down PLK1-Mis18 interactions to a single residue in Mis18a and two residues in Mis18BP1. We then structurally validated the interactions by crystallizing the Polo- Box Domain of PLK1 with phosphopeptides of Mis18a and Mis18BP1 and solving the crystal structures using X-ray crystallography. Cell-based assays were performed to demonstrate that phosphomimic mutants of Mis18a and Mis18BP1 mimicking PLK1 phosphorylation enhance new CENP-A loading at endogenous centromeres, whereas non-phosphorylatable mutants lead to a reduction of CENP-A loading. Cross-linking studies from our lab have shown that the N-terminal a-helix of Mis18a make extensive contacts with its C-terminal a-helix and our MS data analysis reports that phosphorylation sites in Mis18a are mostly enriched in the N-terminal aVII helical region. It has also been previously reported that HJURP binds C-terminus of the Mis18a/b complex more efficiently upon removal of the N-terminal a-helix of Mis18a. Considering the location of phosphorylation sites in Mis18a and that our in vivo data suggests an increase in CENP-A levels, we hypothesize that structural reorganization of the Mis18 complex occurs upon PLK1 phosphorylation that influences its interaction with HJURP thus enhancing CENP-A loading. In summary, this work demonstrates that PLK1, in addition to its previously known role of promoting centromere localization of the Mis18 complex, directly modulates CENP-A loading, most likely by influencing the binding of HJURP to the Mis18 complex.

Published
2023
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6. Citation inequity and gendered citation practices in contemporary physics

Author

Teich, Erin G., Kim, Jason Z., Lynn, Christopher W., Simon, Samantha C., Klishin, Andrei A., Szymula, Karol P., Srivastava, Pragya, Bassett, Lee C., Zurn, Perry, Dworkin, Jordan D., and Bassett, Dani S.

Subjects
Physics - Physics and Society, Computer Science - Digital Libraries
Abstract

The historical and contemporary under-attribution of women's contributions to scientific scholarship is well-known and well-studied, with effects that are felt today in myriad ways by women scientists. One measure of this under-attribution is the so-called citation gap between men and women: the under-citation of papers authored by women relative to expected rates coupled with a corresponding over-citation of papers authored by men relative to expected rates. We explore the citation gap in contemporary physics, analyzing over one million articles published over the last 25 years in 35 physics journals that span a wide range of subfields. Using a model that predicts papers' expected citation rates according to a set of characteristics separate from author gender, we find a global bias wherein papers authored by women are significantly under-cited, and papers authored by men are significantly over-cited. Moreover, we find that citation behavior varies along several dimensions, such that imbalances differ according to who is citing, where they are citing, and how they are citing. Specifically, citation imbalance in favor of man-authored papers is highest for papers authored by men, papers published in general physics journals, and papers likely to be less familiar to citing authors. Our results suggest that, although deciding which papers to cite is an individual choice, the cumulative effects of these choices needlessly harm a subset of scholars. We discuss several strategies for the mitigation of these effects, including conscious behavioral changes at the individual, journal, and community levels.

Published
2021
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7. The information content of brain states is explained by structural constraints on state energetics

Author

Weninger, Leon, Srivastava, Pragya, Zhou, Dale, Kim, Jason Z., Cornblath, Eli J., Bertolero, Maxwell A., Habel, Ute, Merhof, Dorit, and Bassett, Dani S.

Subjects
Quantitative Biology - Neurons and Cognition, Physics - Biological Physics, 93-08 (primary), 92-08, 94-05 (secondary), G.3, H.1.1, J.3
Abstract

Signal propagation along the structural connectome of the brain induces changes in the patterns of activity. These activity patterns define global brain states and contain information in accordance with their expected probability of occurrence. The structural connectome, in conjunction with the dynamics, determines the set of possible brain states and constrains the transition between accessible states. Yet, precisely how these structural constraints on state-transitions relate to their information content remains unexplored. To address this gap in knowledge, we defined the information content as a function of the activation distribution, where statistically rare values of activation correspond to high information content. With this numerical definition in hand, we studied the spatiotemporal distribution of information content in fMRI data from the Human Connectome Project during different tasks, and report four key findings. First, information content strongly depends on the cognitive task. Second, while information content shows similarities to other measures of brain activity, it is distinct from both Neurosynth maps and task contrast maps generated by a general linear model applied to the fMRI data. Third, the brain's structural wiring constrains the cost to control its state, where the cost to transition into high information content states is larger than that to transition into low information content states. Finally, all state transitions - especially those to high information content states - are less costly than expected from random network null models, thereby indicating the brain's marked efficiency. Taken together, our findings establish an explanatory link between the information contained in a brain state and the energetic cost of attaining that state, thereby laying important groundwork for our understanding of large-scale cognitive computations., Comment: 16 pages, 4 figures + supplement (5 pages, 5 figures)

Published
2021
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8. Structural underpinnings of control in multiplex networks

Author

Srivastava, Pragya, Mucha, Peter J., Falk, Emily, Pasqualetti, Fabio, and Bassett, Danielle S.

Subjects
Quantitative Biology - Neurons and Cognition, Physics - Biological Physics
Abstract

To design control strategies that predictably manipulate a system's behavior, it is first necessary to understand how the system's structure relates to its response. Many complex systems can be represented as multilayer networks whose response and control can be studied in the framework of network control theory. It remains unknown how a system's layered architecture dictates its control properties, particularly when control signals can only access the system through a single input layer. Here, we use the framework of linear control theory to probe the control properties of a duplex network with directed interlayer links. We determine the manner in which the structural properties of layers and relative interlayer arrangement together dictate the system's response. For this purpose, we calculate the exact expression of optimal control energy in terms of layer spectra and the relative alignment between the eigenmodes of the input layer and the deeper target layer. For a range of numerically constructed duplex networks, we then calculate the control properties of the two layers as a function of target-layer densities and layer topology. The alignment of layer eigenmodes emerges as an important parameter that sets the cost and routing of the optimal energy for control. We understand these results in a simplified limit of a single-mode approximation, and we build metrics to characterize the routing of optimal control energy through the eigenmodes of each layer. Our analytical and numerical results together provide insights into the relationships between structure and control in duplex networks. More generally, they serve as a platform for future work designing optimal \emph{interlayer} control strategies., Comment: 14 pages, 5 figures, 19 pages supplementary material, 10 supplementary figures

Published
2021

9. Models of communication and control for brain networks: distinctions, convergence, and future outlook

Author

Srivastava, Pragya, Nozari, Erfan, Kim, Jason Z., Ju, Harang, Zhou, Dale, Becker, Cassiano, Pasqualetti, Fabio, and Bassett, Danielle S.

Subjects
Quantitative Biology - Neurons and Cognition, Physics - Biological Physics
Abstract

Recent advances in computational models of signal propagation and routing in the human brain have underscored the critical role of white matter structure. A complementary approach has utilized the framework of network control theory to better understand how white matter constrains the manner in which a region or set of regions can direct or control the activity of other regions. Despite the potential for both of these approaches to enhance our understanding of the role of network structure in brain function, little work has sought to understand the relations between them. Here, we seek to explicitly bridge computational models of communication and principles of network control in a conceptual review of the current literature. By drawing comparisons between communication and control models in terms of the level of abstraction, the dynamical complexity, the dependence on network attributes, and the interplay of multiple spatiotemporal scales, we highlight the convergence of and distinctions between the two frameworks. Based on the understanding of the intertwined nature of communication and control in human brain networks, this work provides an integrative perspective for the field and outlines exciting directions for future work., Comment: 23 pages, 4 figures

Published
2020
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10. Swimmer suspensions on substrates: anomalous stability and long-range order

Author

Maitra, Ananyo, Srivastava, Pragya, Marchetti, M. Cristina, Ramaswamy, Sriram, and Lenz, Martin

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Statistical Mechanics, Physics - Biological Physics
Abstract

We present a comprehensive theory of the dynamics and fluctuations of a two-dimensional suspension of polar active particles in an incompressible fluid confined to a substrate. We show that, depending on the sign of a single parameter, a state with polar orientational order is anomalously stable (or anomalously unstable), with a nonzero relaxation (or growth) rate for angular fluctuations at zero wavenumber. This screening of the broken-symmetry mode in the stable state does lead to conventional rather than giant number fluctuations as argued by Bricard et al., Nature ${\bf 503}$, 95 (2013), but their bend instability in a splay-stable flock does not exist and the polar phase has long-range order in two dimensions. Our theory also describes confined three-dimensional thin-film suspensions of active polar particles as well as dense compressible active polar rods, and predicts a flocking transition without a banding instability

Published
2019
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12. Low-Power and High-Speed Design of FinFET-Based MCML Delay Element

Author

Srivastava, Pragya, Yadav, Richa, Srivastava, Richa, Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Rawat, Sanyog, editor, Kumar, Arvind, editor, Kumar, Pramod, editor, and Anguera, Jaume, editor

Published
2022
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13. Power Efficient Analysis of MOS Current Mode Logic Based Delay Flip Flop

Author

Suhail, Ramsha, Srivastava, Pragya, Yadav, Richa, Srivastava, Richa, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Hirche, Sandra, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Möller, Sebastian, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Zhang, Junjie James, Series Editor, Lenka, Trupti Ranjan, editor, Misra, Durgamadhab, editor, and Biswas, Arindam, editor

Published
2022
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14. Stability from activity

Author

Maitra, Ananyo, Srivastava, Pragya, Marchetti, M. Cristina, Lintuvuori, Juho, Ramaswamy, Sriram, and Lenz, Martin

Subjects
Condensed Matter - Soft Condensed Matter, Condensed Matter - Statistical Mechanics, Physics - Biological Physics
Abstract

Suspensions of actively driven anisotropic objects exhibit distinctively nonequilibrium behaviors, and current theories predict that they are incapable of sustaining orientational order at high activity. By contrast, here we show that nematic suspensions on a substrate can display order at arbitrarily high activity due to a previously unreported, potentially stabilizing active force. The resulting nonequilibrium ordered phase displays robust giant number fluctuations that cannot be suppressed even by an incompressible solvent. Our results apply to virtually all experimental assays used to investigate the active nematic ordering of self-propelled colloids, bacterial suspensions and the cytoskeleton, and have testable implications in interpreting their nonequilibrium behaviors

Published
2017

18. Negative stiffness and modulated states in active nematics

Author

Srivastava, Pragya, Mishra, Prashant, and Marchetti, M. Cristina

Subjects
Condensed Matter - Soft Condensed Matter
Abstract

We examine the dynamics of a compressible active nematic liquid crystal on a frictional substrate. When frictional damping dominates over viscous dissipation, we eliminate flow in favor of active stresses to obtain a minimal dynamical model for the nematic order parameter, with elastic constants renormalized by activity. The renormalized elastic constants can become negative at large activity, leading to the selection of spatially inhomogeneous patterns via a mechanism analogous to that responsible for modulated phases arising at an equilibrium Lifshitz point. Tuning activity and the degree of nematic order in the passive system, we obtain a linear stability phase diagram that exhibits a nonequilibrium tricritical point where ordered, modulated and disordered phases meet. Numerical solution of the nonlinear equations yields a succession of spatial structures of increasing complexity with increasing activity, including kink walls and active turbulence, as observed in experiments on microtubule bundles confined at an oil-water interface. Our work provides a minimal model for an overdamped active nematic that reproduces all the nonequilibrium structures seen in simulations of the full active nematic hydrodynamics and provides a framework for understanding some of the mechanisms for selection of the nonequilibrium patterns in the language of equilibrium critical phenomena., Comment: 12 pages, 7 figures, 8 supplementary movies

Published
2016
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20. Activating membranes

Author

Maitra, Ananyo, Srivastava, Pragya, Rao, Madan, and Ramaswamy, Sriram

Subjects
Physics - Biological Physics, Condensed Matter - Soft Condensed Matter, Condensed Matter - Statistical Mechanics
Abstract

We present a general dynamical theory of a membrane coupled to an actin cortex containing polymerizing filaments with active stresses and currents, and demonstrate that active membrane dynamics [Phys. Rev. Lett \textbf{84}, 3494 (2000)] and spontaneous shape oscillations emerge from this description. We also consider membrane instabilities and patterns induced by the presence of filaments with polar orientational correlations in the tangent plane of the membrane. The dynamical features we predict should be seen in a variety of cellular contexts involving the dynamics of the membrane-cytoskeleton composite and cytoskeletal extracts coupled to synthetic vesicles.

Published
2013
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23. Patterning of polar active filaments on a tense cylindrical membrane

Author

Srivastava, Pragya, Shlomovitz, Roie, Gov, Nir S., and Rao, Madan

Subjects
Condensed Matter - Soft Condensed Matter, Physics - Biological Physics, Quantitative Biology - Subcellular Processes
Abstract

We study the dynamics and patterning of polar contractile filaments on the surface of a cylindrical cell using active hydrodynamic equations that incorporate couplings between curvature and filament orientation. Cables and rings spontaneously emerge as steady state configurations on the cylinder, and can be stationary or moving, helical or segments moving along helical trajectories. Contractility induces coalescence of proximal rings. We observe phase transitions in the steady state patterns upon changing cell diameter and make several testable predictions. Our results are relevant to the dynamics and patterning of a variety of active biopolymers in cylindrical cells., Comment: 10 pages, 8 figures, (Includes Supplementary information)

Published
2012
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26. Mechanistic basis for PLK1-mediated regulation of centromere maintenance

Author

Pragya, Srivastava, Pragya, Arulanandam, Arockia Jeyaprakash, Heun, Patrick, and Darwin Trust

Subjects
PLK1-mediated regulation, DNA replication-mediated dilution of CENP-A levels, identical segregation of chromosomes, centromeric region of the chromosomes, binding of HJURP to the Mis18 complex, accurate chromosome segregation, centromere maintenance, Equal segregation of chromosomes, eukaryotes, nucleosomes containing CENP-A, spindle microtubules, histone H3 variant, cell cycle, CENP-A
Abstract

Equal and identical segregation of chromosomes during each round of the cell cycle is essential for the faithful transmission of the genetic material. An important factor for accurate chromosome segregation is the stable attachment of spindle microtubules to the centromeric region of the chromosomes. In most eukaryotes, centromeres are epigenetically defined by the enrichment of nucleosomes containing CENP-A, a histone H3 variant. DNA replication-mediated dilution of CENP-A levels occurs as the existing CENP-A is distributed among the two DNA strands during the S-phase. In order to preserve centromere identity, CENP-A levels must be restored in a cell-cycle controlled manner. In humans, new CENP-A deposition occurs during the G1 phase and involves coordinated actions of several proteins. The Mis18 complex (Mis18a, Mis18b, Mis18BP1) is the central player in centromere maintenance that is recruited to the centromeres by CENP-C. Once the Mis18 complex localizes to the centromere, it recruits CENP-A-specific chaperone HJURP to deposit new CENP-A nucleosomes. PLK1 has been reported to promote new CENP-A deposition by phosphorylating Mis18BP1 and co-localizing with the Mis18 complex to the centromeres, but the precise mechanism determining its role in the maintenance of centromere identity is yet to be determined. In this study, I demonstrate that PLK1 interacts with the Mis18 complex via Mis18a and Mis18BP1 subunits in a phosphorylation-dependent manner via selfprimed phosphorylations. Mass spectrometry and biochemical assays were used to narrow down PLK1-Mis18 interactions to a single residue in Mis18a and two residues in Mis18BP1. We then structurally validated the interactions by crystallizing the Polo- Box Domain of PLK1 with phosphopeptides of Mis18a and Mis18BP1 and solving the crystal structures using X-ray crystallography. Cell-based assays were performed to demonstrate that phosphomimic mutants of Mis18a and Mis18BP1 mimicking PLK1 phosphorylation enhance new CENP-A loading at endogenous centromeres, whereas non-phosphorylatable mutants lead to a reduction of CENP-A loading. Cross-linking studies from our lab have shown that the N-terminal a-helix of Mis18a make extensive contacts with its C-terminal a-helix and our MS data analysis reports that phosphorylation sites in Mis18a are mostly enriched in the N-terminal aVII helical region. It has also been previously reported that HJURP binds C-terminus of the Mis18a/b complex more efficiently upon removal of the N-terminal a-helix of Mis18a. Considering the location of phosphorylation sites in Mis18a and that our in vivo data suggests an increase in CENP-A levels, we hypothesize that structural reorganization of the Mis18 complex occurs upon PLK1 phosphorylation that influences its interaction with HJURP thus enhancing CENP-A loading. In summary, this work demonstrates that PLK1, in addition to its previously known role of promoting centromere localization of the Mis18 complex, directly modulates CENP-A loading, most likely by influencing the binding of HJURP to the Mis18 complex.

Published
2023

32. NEOTERIC DESIGN POWER SUSTAINED 3-BIT ASYNCHRONOUS COUNTER USING CNFET BASED MCML TOPOLOGY.

Author

SUHAIL, Ramsha, SRIVASTAVA, Pragya, YADAV, Richa, and SRIVASTAVA, Richa

Subjects
CARBON nanotube field effect transistors, DIGITAL electronics
Abstract

Leading digital circuits namely register, flipflops, state machines and counters drive operational aspects and potential applications in Integrated Circuit (IC) industry. MOS Current Mode Logic (MCML) based implementations with rapid response and simultaneous generation of complemented output is all set to become indispensable in nano regime industry. This paper attempts to optimize and address performancebased analysis of digital circuits namely NAND, D flipflop and 3-bit asynchronous counter by practicing MCML based implementation. These circuits are contemplated on four design parameters namely delay (tp), power (pwr), Power Delay Product (PDP) and Energy Delay Product (EDP). This research focuses on relative analysis and emanate a salient optimal application of Complementary Metal-Oxide-Semiconductor (CMOS) and Carbon Nanotube Field Effect Transistor (CNFET) based 3-bit asynchronous counter. In addition to this, the two configurations of the MCML counter are then compared against applied VDD at 16-nm technology nodes using HSPICE simulator. CNFET based 3-bit MCML counter is observed to be much faster (9.75×), significant improvement in gross power dissipation (11.93×), material refinement in PDP and EDP (116.39× and 1165×) respectively as compared to the conventional counterpart. Therefore, CNFET based implementations comes to the fore as resilient technology supporting high level integration in nano scale regime. [ABSTRACT FROM AUTHOR]

Published
2022
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33. A Brief Study on Social Networks and Feminism

Author

Srivastava, Pragya and Srivastava, Pragya

Abstract

This study investigates the connection between feminism with social networking and assesses social media's potential to serve as an important forum for the promotion of modern feminism goals. Feminism's influence declined in the ages until social networking became an important aspect of society and female viewpoints were sceptical that it might be resurrected or popularised again. In current history, though, people have utilised social networks to collaborate and distribute progressive concepts. The emergence of "hashtag feminism" has resulted in a radical change in the way femininity is practised and argued for in popular society. Educational women are posing a number of important concerns in view of this drastic change in location for female discussions: Is social platforms beneficial to empowerment and the pursuit of egalitarian goals? This article contends that social network has given feminists a voice to tell their experiences, and has helped in the formation of feminist communities. That's also modern feminism most critical work since it makes us more open to progressive values and concepts, changing our world into one that will embrace and battle for feminism's goals. This paper would look at a number of case reports wherein feminist debates have taken social media by storm. It would assess the effect of social networking as a forum for progressive arguments and the usage of social platforms as a feminism medium in the struggle to accomplish feminism's goals.

Published
2021

35. Higher expression of ferritin protects Chlamydia trachomatis infected HeLa 229 cells from reactive oxygen species mediated cell death

Author

Vardhan, Harsh, Bhengraj, Apurb Rashmi, Jha, Rajneesh, Srivastava, Pragya, Jha, Hem Chandra, and Mittal, Aruna

Subjects
Biochemistry -- Physiological aspects -- Research, Cell death -- Research -- Prevention -- Physiological aspects, Chlamydia -- Physiological aspects -- Research, Chlamydia infections -- Research -- Physiological aspects -- Prevention, Apoptosis -- Research -- Physiological aspects, Reactive oxygen species -- Research -- Properties -- Physiological aspects, Ferritin -- Research -- Properties -- Physiological aspects, Chlamydia trachomatis -- Research -- Physiological aspects, Biological sciences
Abstract

Apoptosis plays an important role in modulating the pathogenesis of a variety of infectious diseases. Chlamydial infection protects cells against different forms of apoptosis: extrinsic, intrinsic, and granzyme B mediated. Redox reactions are central to the life and death decision of cells and pathogens and an intimate relationship exists between oxidative stress and iron metabolism. The link between redox status and ferritin was largely unexplored in chlamydia-infected cells. In the present study, we showed that Chlamydia trachomatis (CT) infection induced FHC protein in HeLa cells. FHC induction by CT-infected cells stably expressing FHC blunted ROS production compared with mock infected cells, and the infected cells were relatively resistant to apoptosis induced by [H.sub.2][O.sub.2]. We also demonstrated that endogenous FHC overexpression correlates well with the stabilization of the mitochondrial membrane potential in CT-infected cells. Increased expression of FHC is independent of iron supplementation (FAC) and depletion (DFO) in CT-infected cells. These data suggest that FHC up-regulation is an acute response of HeLa cells against CT infection and that FHC exerts anti-apoptotic activity against oxidative stress. Key words: Chlamydia trachomatis, ferritin, reactive oxygen species, apoptosis, mitochondrial membrane potential. L'apoptose joue un role important dans la modulation de la pathogenese d'une variete de maladies infectieuses. L'infection par la chlamydia protege les cellules contre differentes formes d'apoptose : extrinseque, intrinseque et dependante de la granzyme B. Les reactions d'oxydoreduction sont centrales au cheminement vers la survie ou la mort des cellules et des pathogenes, et il existe un lien etroit entre le stress et le metabolisme du fer. Le lien entre le statut d'oxydoreduction et la ferritine a ete largement negligee chez les cellules infectees par la chlamydia. Dans cette etude, nous avons montre; qu'une infection par Chlamydia trachomatis (CT) induisait la proteine FHC chez les cellules HeLa. L'induction de FHC chez les cellules infectees par CT et exprimant la FHC de facjon stable interrompait la production d'ERO comparativement aux cellules infectees a blanc, et ces cellules eetaient relativement resistantes a l'apoptose induite par le [H.sub.2][O.sub.2]. Nous avons aussi demontree que la surexpression de FHC endogene etait bien relieeea la stabilisation du potentiel membranaire mitochondrial chez les cellules infectees par CT. L'augmentation de l'expression de FHC est independante de la supplementation ou de la depletion en fer chez les cellules infectees par CT. Ces resultats suggerent que la stimulation de l'expression de FHC constitue une reponse aigue des cellules HeLa contre l'infection par CT, et que la FHC exerce une activite anti-apoptotique lors d'un stress oxydant. Mots-cles : Chlamydia trachomatis, ferritine, espeeces reactives d'oxygene, apoptose, potentiel membranaire mitochondrial. [Traduit par la Redaction], Introduction Apoptosis, or programmed cell death, is an evolutionary conserved, strictly regulated, genetic and biochemical program that plays critical roles during development and tissue homeostasis in multicellular organisms (Zakeri and [...]

Published
2010
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36. Seeking career clarity

Author

Antoniou, Chloe, Burnette, Katie, Christensen-Quick, Aaron, Lewinska, Monika, Ji, Yongsheng, Khalifa, Muhammad M, Nikolaou, Athanasia, Srivastava, Pragya, Hollingsworth, Brynn Anne, van Rhijn, Norman, Saurabh, Saumya, Konstantinides, Nikos, Heim, Ashley Barbara, Moore, Eric Britt, Strong, Michael, Kosanic, Aleksandra, Kirshner, Samuel Nathan, Halder, Antarip, Waiho, Khor, Antoniou, Chloe, Burnette, Katie, Christensen-Quick, Aaron, Lewinska, Monika, Ji, Yongsheng, Khalifa, Muhammad M, Nikolaou, Athanasia, Srivastava, Pragya, Hollingsworth, Brynn Anne, van Rhijn, Norman, Saurabh, Saumya, Konstantinides, Nikos, Heim, Ashley Barbara, Moore, Eric Britt, Strong, Michael, Kosanic, Aleksandra, Kirshner, Samuel Nathan, Halder, Antarip, and Waiho, Khor

Published
2020

37. DATS6103-Project 3

Author

Srivastava, Pragya

Abstract

Child Nutrition and Child Mortality Indicators in the last twenty years.

Published
2019
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43. Modulation of cytokines and transcription factors (T-Bet and GATA3) in CD4 enriched cervical cells of Chlamydia trachomatis infected fertile and infertile women upon stimulation with chlamydial inclusion membrane proteins B and C

Author

Salhan Sudha, Srivastava Pragya, Vardhan Harsh, Gupta Rishein, and Mittal Aruna

Subjects
Gynecology and obstetrics, RG1-991, Reproduction, QH471-489
Abstract

Abstract Background Chlamydial Inclusion membrane proteins (Incs), are involved in biochemical interactions with host cells and infecting Chlamydiae. We have previously reported the role of two Chlamydia trachomatis (CT) Incs, namely IncB and IncC in generating host immunity in CT infected women. Emerging data shows involvement of Inc stimulated CD4 positive T cells in aiding host immunity in infected fertile and infertile women through the secretion of interferon gamma. However the lack of data on the intra-cytokine interplay to these Incs in infected cell milieu prompted us to investigate further. Methods A total of 14 CT-positive fertile, 18 CT-positive infertile women and 25 uninfected controls were enrolled in this study. CD8 depleted, CD4 enriched cervical cells were isolated and upon stimulation with IncB and IncC, modulation of cytokines (Interleukin (IL)-1 Beta, IL-4, IL-5, IL-6, IL-10, Interferon-gamma, IL-12, IL-23, Tumor Necrosis Factor-alpha and Granulocyte macrophage colony-stimulating factor (GM-CSF) and T cell lineage regulating transcription factors T-Bet and GATA3 was determined by real-time reverse-transcriptase (RT)-PCR and ELISA. Results Significant higher expression (P < 0.05) of Interferon-gamma, IL-12, IL-23 and GM-CSF were found in Inc-stimulated CD4 enriched cervical cells of CT-positive fertile women and contrastingly high IL-1 Beta, IL-4, IL-5, IL-6 and IL-10 levels were found in CT-positive infertile women. Positive correlation (P < 0.05) was found between Interferon-gamma and T-Bet levels in CT-positive fertile women and IL-4 mRNA and GATA3 levels in CT-positive infertile patients upon IncB and IncC stimulation. Conclusion Overall our data shows that CT IncB and IncC are able to upregulate expression of cytokines, namely interferon-gamma, IL-12, IL-23 and GM-CSF in CT-positive fertile women while expression of IL-1 Beta, IL-4, IL-5, IL-6 and IL-10 were upregulated in CT-positive infertile women. Our study also suggests that Incs are able to modulate expression of T cell lineage determinants indicating their involvement in regulation of immune cells.

Published
2009
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44. Host immune responses to chlamydial inclusion membrane proteins B and C in Chlamydia trachomatis infected women with or without fertility disorders

Author

Salhan Sudha, Vardhan Harsh, Srivastava Pragya, Gupta Rishein, and Mittal Aruna

Subjects
Gynecology and obstetrics, RG1-991, Reproduction, QH471-489
Abstract

Abstract Background With an increase in the number of putative inclusion membrane proteins (incs) in chlamydial genomes, there is a need for understanding their contribution in host-pathogen interactions. Thus in this study we determined the host mucosal and peripheral immune responses to incs (IncB and IncC) of Chlamydia trachomatis (CT). Methods Female patients (n = 296) attending the gynaecology out patient department of Safdarjung hospital, New Delhi were enrolled for the study and were clinically characterized into two groups; CT-positive fertile women (n = 38) and CT-positive women with fertility disorders (n = 29). Uninfected healthy fertile women were enrolled as controls (n = 31). Gene specific PCRs were used for detection of incB and incC genes in endocervical samples of CT-positive patients. ELISA and Western blot assay were used for detection of IgA and IgG antibodies to IncB and IncC in cervical washes and sera. Effect of IncB and IncC stimulation of cervical cells and PBMCs on cellular proliferation and cytotoxity was determined using MTT assay and Lactate dehydrogenase (LDH)-cytotoxicity assay respectively. Modulation of cytokines (Interleukin (IL)-1 Beta, IL-4, IL-5, IL-6, IL-10, Interferon-gamma, IL-12, Tumor Necrosis Factor-alpha and Granulocyte macrophage colony-stimulating factor (GM-CSF)) in cervical cells and PBMCs upon stimulation with IncB and IncC was determined by real-time reverse-transcriptase (RT)-PCR and ELISA. Further, CD4 positive T cells were purified from cervical cells and peripheral blood mononuclear cells (PBMCs) and secreted cytokines (Interferon-gamma and IL-4) were evaluated by ELISPOT and real-time RT-PCR. Results Using MTT assay, significantly high proliferative responses (P < 0.05) were observed in inc-stimulated cervical cells and PBMCs from CT-positive fertile women compared to CT-positive women with fertility disorders and controls. Interferon-gamma, IL-12 and GM-CSF were found to be elevated in inc-stimulated cervical cells and PBMCs of CT-positive fertile women compared to CT-positive women with fertility disorders and controls (P < 0.05). In contrast, IL-1 Beta, IL-4, IL-5, IL-6 and IL-10 levels were found to be higher in CT-positive women with fertility disorders compared to CT-positive fertile women and controls (P < 0.05). Interferon-gamma secreting cells and mRNA expression in inc-stimulated cervical and peripheral CD4 positive T cells were significantly higher (P < 0.05) in CT positive fertile women compared to CT-positive women with fertility disorders. Conclusion Our data overall suggests that CT incs, IncB and IncC modulate host immune responses and may have a role in protection/pathogenesis of genital chlamydial infection in women.

Published
2009
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45. In infertile women, cells from Chlamydia trachomatis infected site release higher levels of interferon-gamma, interleukin-10 and tumor necrosis factor-alpha upon heat shock protein stimulation than fertile women

Author

Salhan Sudha, Bas Sylvette, Jha Rajneesh, Srivastava Pragya, and Mittal Aruna

Subjects
Gynecology and obstetrics, RG1-991, Reproduction, QH471-489
Abstract

Abstract Background The magnitude of reproductive morbidity associated with sexually transmitted Chlamydia trachomatis infection is enormous. Association of antibodies to chlamydial heat shock proteins (cHSP) 60 and 10 with various disease sequelae such as infertility or ectopic pregnancy has been reported. Cell-mediated immunity is essential in resolution and in protection to Chlamydia as well as is involved in the immunopathogenesis of chlamydial diseases. To date only peripheral cell mediated immune responses have been evaluated for cHSP60. These studies suggest cHSPs as important factors involved in immunopathological condition associated with infection. Hence study of specific cytokine responses of mononuclear cells from the infectious site to cHSP60 and cHSP10 may elucidate their actual role in the cause of immunopathogenesis and the disease outcome. Methods Female patients (n = 368) attending the gynecology out patient department of Safdarjung hospital, New Delhi were enrolled for the study and were clinically characterized into two groups; chlamydia positive fertile women (n = 63) and chlamydia positive infertile women (n = 70). Uninfected healthy women with no infertility problem were enrolled as controls (n = 39). cHSP60 and cHSP10 specific cytokine responses (Interferon (IFN)-gamma, Interleukin (IL)-10, Tumor Necrosis Factor (TNF)-alpha, IL-13 and IL-4) were assessed by ELISA in stimulated cervical mononuclear cell supernatants. Results cHSP60 and cHSP10 stimulation results in significant increase in IFN-gamma (P = 0.006 and P = 0.04 respectively) and IL-10 levels (P = 0.04) in infertile group as compared to fertile group. A significant cHSP60 specific increase in TNF-alpha levels (P = 0.0008) was observed in infertile group as compared to fertile group. cHSP60 and cHSP10 specific IFN-gamma and IL-10 levels were significantly correlated (P < 0.0001, r = 0.54 and P = 0.004, r = 0.33 respectively) in infertile group. Conclusion Our results suggest that exposure to chlamydial heat shock proteins (cHSP60 and cHSP10) could significantly affect mucosal immune function by increasing the release of IFN-gamma, IL-10 and TNF-alpha by cervical mononuclear cells.

Published
2008
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46. Comparative analysis of chromatin landscape in regulatory regions of human housekeeping and tissue specific genes

Author

Dasgupta Dipayan, Kumar Kaushal, Sutar Sushanta, Srivastava Pragya, Ganapathi Mythily, Pal Singh Gajinder, Brahmachari Vani, and Brahmachari Samir K

Subjects
Computer applications to medicine. Medical informatics, R858-859.7, Biology (General), QH301-705.5
Abstract

Abstract Background Global regulatory mechanisms involving chromatin assembly and remodelling in the promoter regions of genes is implicated in eukaryotic transcription control especially for genes subjected to spatial and temporal regulation. The potential to utilise global regulatory mechanisms for controlling gene expression might depend upon the architecture of the chromatin in and around the gene. In-silico analysis can yield important insights into this aspect, facilitating comparison of two or more classes of genes comprising of a large number of genes within each group. Results In the present study, we carried out a comparative analysis of chromatin characteristics in terms of the scaffold/matrix attachment regions, nucleosome formation potential and the occurrence of repetitive sequences, in the upstream regulatory regions of housekeeping and tissue specific genes. Our data show that putative scaffold/matrix attachment regions are more abundant and nucleosome formation potential is higher in the 5' regions of tissue specific genes as compared to the housekeeping genes. Conclusion The differences in the chromatin features between the two groups of genes indicate the involvement of chromatin organisation in the control of gene expression. The presence of global regulatory mechanisms mediated through chromatin organisation can decrease the burden of invoking gene specific regulators for maintenance of the active/silenced state of gene expression. This could partially explain the lower number of genes estimated in the human genome.

Published
2005
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47. Breakup among Medical Students: Aftermath and Resumption.

Author

Wadhawan, Jahnvi, Srivastava, Pragya, Agrawal, Pranjal, Jindal, Prachi, Singh, Divyansh, Sharma, Saurabh, and Ahmed, Sartaj

Subjects
MEDICAL students, JEALOUSY, PSYCHOLOGICAL distress, PSYCHOLOGICAL stress, ANXIETY, CROSS-sectional method, EXTREME sports
Abstract

Breakup is a metaphor for intense emotional and most distressing events in which one feels at experiencing great & deep longing. The person is broken into pieces, reaches rock bottom & may go in the very depressed state of life. To overcome this feeling, one may indulge in positive or negative activities. A person may have the extreme emotional energy, be it jealousy, depression, insecurity, stress, or anxiety, which needs to come out. This study was done with objectives of assessing the frequency and pattern of a breakup, change in Physical, Mental, Social & Spiritual Health concerning breakup and compare the change in productivity immediately after a breakup and 8 weeks (2months) after breakup. Materials and Methods: This was a cross-sectional study done among 378 MBBS students in a medical college of North India. A pre structured, pretested, pre-validated, and close-ended questionnaire was used in the study Results: In our study, 104(27.5%) of medical students experienced a breakup in their life. Among 104(27.5%) who experienced a breakup, 52(50%) were males and 52(50%) were females. Various emotional experiences of students during the breakup were being depressed, stressed, sense of relief, and neutral. Spiritual practice was found to be effective in overcoming the emotional stress of breakup and increased post-breakup productivity. Indulgence in hobbies and health care activities were commonest activities done just after a breakup to overcome it. Conclusion: Breakups are common among medical students, spiritual orientation and involvement in hobbies help students to overcome breakup stress and increase their productivity hence in medical education there should be a special place for spiritual orientation. [ABSTRACT FROM AUTHOR]

Published
2020
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49. Phytochemical Screening and In-VitroAntibacterial and Anticancer Activity of Crude Extract of Matricaria aurea

Author

Ahmad, Irfan, Mir, Mushtaq A., Srivastava, Saurabh, Shati, Ali A., Elbehairi, Serag Eldin I., Irfan, Safia, Abohashrh, Mohammed, Nisar, Nazima, Bashir, Nasreena, and Srivastava, Pragya

Abstract

Background: Infectious diseases constantly represent the source of sickness as well as mortality in human beings. Herbal applications in human life through using plants for antibacterial and anticancer activity have shown the potential medicinal outcome. Objectives: To evaluate the antibacterial and anticancer activities of the crude extract of Matricaria aurea. Materials and Methods: The antibacterial activity of the crude flowers of M. aurea extract was examined against reference and clinical bacterial strains by agar well diffusion method. Minimum inhibitory concentrations and minimum bactericidal concentrations were determined by micro broth dilution assays using MH broth. Herbal extract was employed over human breast adenocarcinoma cell line (MCF-7), hepatocellular carcinoma cell line (HepG-2) and colorectal adenocarcinoma cell line (HCT-116) to optimize cancer cells proliferation by SRB assay. Results: The data has shown that the extract from M. aurea had significant antimicrobial activity against the tested microorganisms. The plant extract showed higher antibacterial activity against the reference strain of Streptococcus pyogenes. The MIC and MBC varied between 0.38-12.5 mg/ml and 3.1-200 mg/ml respectively. Synergy study elucidated the significant bacteriostatic effect of M. aurea extract on S. aureus and S. saprophyticus. The data of SRB assay deliver the potential anticancer activity through cell death. Conclusion: This study delivers innovative information that M. aurea possessed excellent bio-activities against pathogenic microbes and cancer cells, which drive attention for further research to explore the active components responsible for biological efficacies.

Published
2021
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