ISAJ Newsletter - Volume 2, Issue 1 (February 2017)

From the Editor’s Desk

Greetings and a warm welcome to the first issue of ISAJ Newsletter for 2017!

Since this is the very first issue of the year, we take this opportunity to wish you all a happy and very productive 2017. May all your dreams come true during this year.

In this issue, we present four articles dealing with diverse topics. In the wake of two recent devastating earthquakes in the Asian region: the April 2015 Nepal earthquake (Gorkha earthquake) and the April 2016 Kumamoto earthquakes, we present insightful thoughts about lessons learned from these catastrophic disasters, focusing on the importance of mainstreaming disaster risk reduction, especially for India which has densely populated urban sprawls in seismically active regions.

Research Spotlight: Mainstreaming Disaster Risk Reduction

By Dr. Shanthanu R. Menon, Engineering Consultant, Kozo Keikaku Inc., Tokyo

Nepal suffered heavy damage in 2015 due to the series of earthquakes that struck in and around the Kathmandu Valley (The Gorkha Earthquake). The events reminded the world about the devastating capabilities of natural hazards. The earthquakes exposed the vulnerability of certain building types, particularly brick buildings with mud mortar.

Key Challenges

Research in earthquake engineering faces multiple challenges:

• Bridging the Gap: Between academic research and actual practices to provide practical engineering solutions
• Learning from Experience: Japan’s abundant experience in tackling natural hazards provides valuable lessons
• Mainstreaming Strategy: How to reach out to masses and increase community awareness against natural hazards

India’s Precarious Position

Many regions in India face critical risks:

• Densely populated urban sprawls in seismically active regions
• Relatively weak building infrastructure
• Impending risk of large-scale disaster

The challenge involves not only the research community and bureaucrats but every citizen of the country in building disaster resilience.

Research Update: Grain-Size Effect on Mechanical Behavior of Pure Magnesium

By Mohit Joshi, Kyoto University

Global warming concerns have led to recommendations for using light materials like Aluminum, Magnesium, or polymeric composites for energy-efficient product designs. Magnesium-based alloys are the lightest among structural metallic materials with high strength-to-weight ratio, better heat dissipation, electromagnetic shielding, and recyclability than polymer composites.

Research Findings

To improve mechanical properties of magnesium:

• Fine-grained microstructure: Average grain size of 2.3 μm
• Coarse-grained microstructure: Average grain size of 7.8 μm
• Results: Fine-grained specimens showed 50% improvement in both yield strength and ductility

This breakthrough suggests grain-refinement can be used to improve mechanical properties of other magnesium-based alloys, advancing lightweight structure innovation across automotive, aerospace, and electronics industries.

From the Pen of Young Mind: Numerical Simulation of Bubbly Flows in Aeration Tank

By Khateeb Noor Ul Huda, The University of Tokyo

Research Purpose

Development of a comprehensive model representing wastewater treatment reactor using bubble plume system as the reaction tank, incorporating all biochemical reactions numerically.

Technical Details

• Biological Reactions: Aerobic and Anaerobic/Anoxic reactions
• System Complexity: 14 different bacteria types and 50+ substrates
• Methodology: Activated Sludge system for aerobic reactions, Monod kinetics
• Validation: Error between study and model slopes approximately 3.5%

Key Findings

• 100 μm bubble radius gives best results due to small size and high dissolution
• 500 μm performs better than 250 μm due to internal circulation
• Model successfully represents biological wastewater purification with complex bacterial reactions

From the Pen of Young Mind: Motilin and Ghrelin Affecting Gastrointestinal Motility

By Amrita Dudani, Saitama University

The gastrointestinal tract is the body’s largest endocrine organ. Motilin and Ghrelin hormones comprise a gut peptide hormone family regulating gastrointestinal motility - the movement of the digestive system and transit of contents.

Research Approach

Using Suncus murinus (Asian house shrew) as a model:

• Examined fundus, upper corpus, lower corpus, and antrum regions
• Conducted in-vitro organ bath experiments
• Measured mRNA expression of receptors GPR38 and GHSR

Key Discovery

This is the first report suggesting that the proximal stomach (fundus and upper corpus) is most sensitive and responsive to motilin- and ghrelin-induced synergistic gastric contractions. The findings have potential clinical applications for developing motilin/ghrelin-derived compounds.

7th ISAJ Symposium 2016 Highlights

The 7th Annual ISAJ Symposium was successfully held on December 15, 2016, at the Embassy of India Auditorium, Tokyo. The event featured:

• Inaugural lamp lighting ceremony
• Multiple poster sessions showcasing cutting-edge research
• Interactive tea/coffee breaks for networking
• Strong participation from both Indian and Japanese scientific communities

The symposium continued ISAJ’s tradition of fostering collaboration and knowledge exchange between researchers from both nations.