Quantifying the rise and fall of scientific fields

Science advances by pushing the boundaries of the adjacent possible. While the global scientific enterprise grows at an exponential pace, at the mesoscopic level the exploration and exploitation of research ideas is reflected through the rise and fall of research fields. The empirical literature has largely studied such dynamics on a case-by-case basis, with a focus on explaining how and why communities of knowledge production evolve. Although fields rise and fall on different temporal and population scales, they are generally argued to pass through a common set of evolutionary stages. To understand the social processes that drive these stages beyond case studies, we need a way to quantify and compare different fields on the same terms. In this paper we develop techniques for identifying scale-invariant patterns in the evolution of scientific fields, and demonstrate their usefulness using 1.5 million preprints from the arXiv repository covering 175 research fields spanning Physics, Mathematics, Computer Science, Quantitative Biology and Quantitative Finance. We show that fields consistently follows a rise and fall pattern captured by a two parameters right-tailed Gumbel temporal distribution. We introduce a field-specific rescaled time and explore the generic properties shared by articles and authors at the creation, adoption, peak, and decay evolutionary phases. We find that the early phase of a field is characterized by the mixing of cognitively distant fields by small teams of interdisciplinary authors, while late phases exhibit the role of specialized, large teams building on the previous works in the field. This method provides foundations to quantitatively explore the generic patterns underlying the evolution of research fields in science, with general implications in innovation studies.Comment: 18 pages, 4 figures, 8 SI figure

Structure and evolution of Indian physics co-authorship networks

We trace the evolution of Indian physics community from 1919 to 2013 by analyzing the co-authorship network constructed from papers published by authors in India in American Physical Society (APS) journals. We make inferences on India’s contribution to different branches of Physics and identify the most influential Indian physicists at different time periods. The relative contribution of India to global physics publication (research) and its variation across subfields of physics is assessed. We extract the changing collaboration pattern of authors between Indian physicists through various network measures. We study the evolution of Indian physics communities and trace the mean life and stationarity of communities by size in different APS journals. We map the transition of authors between communities of different sizes from 1970 to 2013, capturing their birth, growth, merger and collapse. We find that Indian–Foreign collaborations are increasing at a faster pace compared to the Indian–Indian. We observe that the degree distribution of Indian collaboration networks follows the power law, with distinct patterns between Physical Review A, B and E, and high energy physics journals Physical Review C and D, and Physical Review Letters. In almost every measure, we observe strong structural differences between low-energy and high-energy physics journals.by Chakresh Kumar Singh, and Shivakumar Jola

Exploring the role and nature of interactions between institutes in a local affiliation network

by Chakresh Kumar Singh, Ravi Vishwakarma and Shivakumar Jola

Investigating the interdependency between collaboration networks

by Chakresh Kr. Singh,Demival Vasques Filho and Dion O'Neal

A study among school-going adolescent girls in Rewa city, Madhya Pradesh, India: awareness and practices regarding menstruation

Introduction The World Health Organization defines adolescence as 10-19 years of age. In India, as per the most recent 2011 census, the adolescent population is 253 million, a quarter of the country’s total population. Menarche is an important milestone in a girl’s life and the beginning of her reproductive life. Menstruation is a challenge for many girls, as lack of sanitary products restricts their involvement in education and social activities. The aim of this study was to estimate menstrual awareness and hygiene practices among school-going adolescent girls

Charting mobility patterns in the scientific knowledge landscape

Abstract From small steps to great leaps, metaphors of spatial mobility abound to describe discovery processes. Here, we ground these ideas in formal terms by systematically studying mobility patterns in the scientific knowledge landscape. We use low-dimensional embedding techniques to create a knowledge space made up of 1.5 million articles from the fields of physics, computer science, and mathematics. By analyzing the publication histories of individual researchers, we discover patterns of scientific mobility that closely resemble physical mobility. In aggregate, the trajectories form mobility flows that can be described by a gravity model, with jumps more likely to occur in areas of high density and less likely to occur over longer distances. We identify two types of researchers from their individual mobility patterns: interdisciplinary explorers who pioneer new fields, and exploiters who are more likely to stay within their specific areas of expertise. Our results suggest that spatial mobility analysis is a valuable tool for understanding the evolution of science

Investigating the interdependence of citation and co-authorship networks

by Chakresh Kumar Singh, Demival Vasques Filho, Shivakumar Jolad and Dion O'Neal

fMRI: A Benediction to Neuroscience

Functional Magnetic Resonance Imaging (fMRI) is a looming technique utilized to study local brain functions in vivo on a large dimensional and temporal resolution. The technique is less expensive and completely noninvasive hence it has swiftly become one of the most preferred choices for brain mapping. It establishes on Magnetic Resonanc e Imaging and helps to identify neural correlations and brain-behavior relationship by detecting the changes in blood flow.fMRI is one of the most frequently used technique in the field of neuroscience which has provided researchers with unparalleled access to the brain in action. The imaging data generated from different neuroimaging techniques (primarily fMRI) is a time series data. A typical fMRI study provides huge volume of noisy data with a complex spatio-temporal correlation configuration. Statistics play a vital stint in apprehending the attributes of the data and gaining appropriate conclusions that can be used and understood by neuroscientists.The data is huge and is characterized by volume, velocity, variety and veracity. These attributes makes it fall under big data further raising the issues of big data analytics. Upcoming technologies such as cloud computing, Spark and massive parallel computational methods /algorithms could provide the possible solutions for analysis and mining of data. The review highlights fMRI as a source of Big Neuroimaging data, different databases & repositories where data is available, its role in healthcare, problems in the data analysis and how the present technologies provide possible solutions for data analysis

Simulative Investigation of the Hybrid, Spatially Multiplexed MIMO-FSO Transmission System Under Atmospheric Turbulence

An orbital angular momentum (OAM) technology, which uses twisted helical phase structure laser modes to carry multiplexed information, has shown excellent potential to improve the capacity of the free space optical communication (FSO) system under atmospheric turbulence (AT) conditions. A significant challenge in an OAM-based FSO transmission system is the optical signal power fading and induced crosstalk due to abrupt changes in atmospheric turbulence. This research paper, presents a design of a hybrid, spatially multiplexed MIMO-FSO transmission system that incorporates the features of 16-QAM, OAM, and OFDM techniques with spatial mode diversity (SMD) to achieve high transmission rates and channel capacity with reduced power penalty during mitigating the multipath fading effects in different turbulent atmospheric channel conditions. The simulation based results illustrate that the hybrid, spatially multiplexed MIMO-FSO system achieves superior BER performance for the transmission link of 2 km with a forward error correction (FEC) threshold limit of $3.8 \times 10^{-3}$ . The Gamma-Gamma (GG) turbulent model is used to analyze the system performance under various atmospheric turbulence conditions in terms of the optical signal to noise ratio (OSNR), number of subcarriers, OAM states, channel capacity, and power penalty. Comparing with the OAM-multiplexed and OFDM-based FSO transmission system, the capacity performance of the proposed system is significantly improved, and the average improvement is obtained at 650% and 856.04% respectively, at 10 dB OSNR. Furthermore, the result clearly showing a 1.5 dB reduction in power penalty with an increase in transmitter lens aperture at a fixed lateral displacement (LD) of 1.5 mm. For large transmitter beam diameters, the power penalty analysis shows an increase in LD tolerance and a decrease in receiver angular error (RAE). A large numerical value of mode spacing leads to a higher-order OAM state, which leads to high power loss but less inter-channel crosstalk due to beam divergence

Organization of functional brain networks under external

by Richa Tripathi, Dyutiman Mukhopadhyay, Chakresh Kumar Singh, Krishna Prasad Miyapuram and Shivakumar Jola