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This study aims to provide a review for scour in complex rivers and streams with coarser bed material, steep longitudinal bed slopes and dynamic environments, in the interest of the safety and the economy of hydraulic structures. The knowledge of scour in such geographical complexities is very crucial for a comprehensive understanding of scour failures and for establishing definitive criteria to bridge this major research gap.

The existing available literature shows significant work done in case of silt, sand and small sized coarser bed material but any substantial work for bed material of gravel size or above is lacking, resulting in a wide gap. Though some researchers have attempted to explore possibilities of refining the existing models by adding pier size, shape, sediment non-uniformity and armouring effects, which otherwise have been given a miss by the various researchers, including the pioneer in the field Lacey–Inglis (1930). But still, a rational model for scour estimation in such complex conditions for global use is yet to come. This is because all the parameters governing the scour have not been studied properly till date as is evident from the globally available literature and is witnessed in the field too, in recurrent failure of hydraulic structures especially bridges.

The researchers presume that the finer materials move only as a result of erosion. However, in actual field conditions, it has been observed that the large-sized stones also roll down and cause huge erosion along the river bed and damage the hydraulic structures, especially in the steep river/stream beds along hilly slopes. This fact has been overlooked in the models available globally and has been highlighted only in the current work in an attempt to recognize this major research gap. A study carried out on a number of streams globally and in Jammu and Kashmir, India also, has shown that in steep river and stream beds with bed material consisting of gravel size or greater than gravel, large scour holes ranging from 1 m to 5 m were created by furious floods, and due to other unknown forces along the channel path and near foundations of hydraulic structures.

To the best of the authors’ knowledge, this work is purely original.

This is a modified version of the 2022 George Herbert Mead Lecture that I delivered at the Annual Meeting of the National Communications Association in New Orleans, LA. Drawing upon ethnographic research with Mississippi River pilots, I outline the strengths and weaknesses of Mead's conceptualization of “mind” as a means to develop the “great cooperative community” he envisioned. I argue that although we possess the cognitive capacity to take the attitude of a multitude of others, even during complex and evolving scenarios, there are also material incentives for some groups to impede the emergence of the mind via the construction of “closed-networks.” I identify one example of a closed-network – professional associations – to demonstrate how and why they attempt to prevent outsiders from role-taking with members of their group. Although the persistence of closed networks hampers Mead's vision of a more co-operative society, it is only by understanding the origins of such barriers to mind that we can address the root causes of their construction.

The present work focuses on evaluating the physical and mechanical characteristics of geopolymer concrete (GPC) by replacing the sodium silicate waste (SSW) in place of traditional river sand. The aim is to create eco-friendly concrete that mitigates the depletion of conventional river sand and conserves natural resources. Additionally, the study seeks to explore how the moisture content of filler materials affects the performance of GPC.

SSW obtained from the sodium silicate industry was used as filler material in the production of GPC, which was cured at ambient temperature. Instead of the typical conventional river sand, SSW was substituted at 25 and 50% of its weight. Three distinct moisture conditions were applied to both river sand and SSW. These conditions were classified as oven dry (OD), air dry (AD) and saturated surface dry (SSD).

As the proportion of SSW increased, there was a decrease in the slump of the GPC. The setting time was significantly affected by the higher percentage of SSW. The presence of angular-shaped SSW particles notably improved the compressive strength of GPC when replacing a portion of the river sand with SSW. When exposed to elevated temperatures, the performance of the GPC with SSW exhibited similar behavior to that of the mix containing conventional river sand, but it demonstrated a lower residual strength following exposure to elevated temperatures.

Exploring the possible utilization of SSW as a substitute for river sand in GPC, and its effects on the performance of the proposed mix. Analyzing, how varying moisture conditions affect the performance of GPC containing SSW. Evaluating the response of the GPC with SSW exposed to elevated temperatures in contrast to conventional river sand.

This chapter analyzes the link between the digital divide, infrastructure regulation, and disaster planning and relief through a case study of the flood in San Jose, California triggered by the Anderson dam’s overtopping in February 2017 and an examination of communication failures during the 2018 wildfire in Paradise, California. This chapter theorizes that regulatory decisions construct social and disaster vulnerability. Rooted in the Whole Community approach to disaster planning and relief espoused by the United Nations and the Federal Emergency Management Agency, this chapter calls for leadership to end the digital divide. It highlights the imperative of understanding community information needs and argues for linking strategies to close the digital divide with infrastructure and emergency planning. As the Internet’s integration into society increases, the digital divide diminishes access to societal resources including disaster aid, and exacerbates wildfire, flood, pandemic, and other risks. To mitigate climate change, climate-induced disaster, protect access to social services and the economy, and safeguard democracy, it argues for digital inclusion strategies as a centerpiece of community-centered infrastructure regulation and disaster relief.

International climate politics are gradually changing in terms of new and ground-breaking policies and decision-making spearheaded by national governments. The growing global demand to combat climate change reflects the current challenges the world is facing. India’s negotiations at United Nations Conference on Climate Change are based on “equity,” “historical responsibility” and the “polluter pays” agenda, until a shift in the voluntary reduction of carbon emissions takes place. The purpose of this study is to understand why India, a “deal breaker”, is seen as a “deal maker” in climate governance?

For a state like India, domestic preferences are equally important in introducing climate policies alongside its concerns over poverty reduction and economic development, which also stand with its sustainable development goals. This paper explains India’s decision-making using a two-level approach focusing on “domestic preferences.” This rationale is based on India’s historical background as well as new upcoming challenges.

This paper shows that India has both the domestic needs and long-term benefits of combating climate change to cut carbon emissions, which gives the responsibility primarily to domestic audiences and international societies.

This paper uses an international political lens to critically analyze India’s climate positions and politics from both domestic and international levels, demonstrating the importance of considering both short- and long-term goals. The outcome benefits not only the policymakers in India but also stakeholders in the Asia-Pacific and beyond.

Using a combination of the geographical information system (GIS) and the Canadian water quality index (WQI), the current study sought to provide a long-term general assessment of the water quality of the Shatt Al-Arab River (SAAR), focusing on its suitability for living organisms. Likewise, SPSS statistics was used to develop a nonlinear WQI regression model for the study area.

The study required four decades of data collection on some environmental characteristics of river water. After that, calculate the WQI and conduct the spatial analysis. Eight variables in total, including water temperature, dissolved oxygen, potential hydrogen ions, electrical conductivity (EC), biological oxygen demand, turbidity, nitrate and phosphate, were chosen to calculate the WQI.

Throughout the study periods, the WQI values varied from 55.2 to 79.83, falling into the categories of four (marginal) and three (fair), with the sixth period (2007–2008) showing the most decline. The present research demonstrated that the high concentration of phosphates, the high EC values, and minor changes in the other environmental factors are the major causes of the decline in water quality. The variations in ecological variables' overlap are a senior contributor to changes in water quality in general. Notably, using GIS in conjunction with the WQI has shown to be very effective in reducing the time and effort spent on investigating water quality while obtaining precise findings and information at the lowest possible expense. Calibration and validation of the developed model showed that this model had a perfect estimate of the WQI value. Due to its flexibility and impartiality, this study recommends using the proposed model to estimate and predict the WQI in the study area.

Even though the water quality of the SAAR has been the subject of numerous studies, this is the only long-term investigation that has been done to evaluate and predict its water quality.

This conversation highlights the need to rethink how we approach disaster risk reduction in different South Asian contexts.

This paper is based on the webinar held as part of Asia Week at the University of Copenhagen which was organised by Asian Dynamics Initiative and Copenhagen Centre for Disaster Research on the September 12, 2023.

The prominent themes emerging from this conversation represents hybridity, self-rule and self-recovery. Along with this we suggest a fundamental turn to ensuring hope, solidarity and empathy is part of a post-colonial future.

The conversation contributes to the ongoing discussions on moving away from colonial practices in disaster risk reduction and disaster studies broadly.

The study aims to investigate how pregnant and nursing mothers’ stories have been neglected in writing about gender, security and spaces.

The study chronicles Agogo Traditional Area’s pregnant and nursing mothers’ resistance and survival in this conflicted environment. The author used photo voices in a participatory photography design to give conflict-area women a voice. Interviews and observations supported this. Pregnant and nursing mothers were sampled using the purposive and snowball sampling techniques. The data analysis considered narrative analysis, photographic and inductive approaches.

The findings highlighted how these mothers in vicious settings experienced healthcare access and problems, societal issues including gender dynamics, food insecurity, and emotional and psychological well-being.

The findings in this study expand the socio-cultural narratives of pregnant and nursing mothers in violent spaces.

This paper aims to focus on scrutinizing the economics of greenhouse gas (GHG) emissions in Vietnam's rice production sector.

Using surveyed data from household rice producers, the smallest available production scale, the author delves into the economics of GHG emissions, constructs a data-driven bottom-up marginal abatement cost curve for Vietnam’s rice production, and evaluates the impacts of carbon pricing on production outputs and GHG emissions.

The author’s estimates reveal that the average profit earned per tonne of GHG emissions is $240/tCO2. Notably, the profit earning per tonne of GHG emissions varies substantially across producers, indicating significant opportunities for improvement among low-efficiency producers. The analysis suggests that a reasonable carbon price would yield a modest impact on the national rice output. The quantitative analysis also reaffirms that the primary driver of GHG emissions in Vietnam’s rice production stems from non-energy inputs and industrial processes rather than the utilisation of energy inputs, emphasizing the importance of improving cultivation techniques.

This research is original.