Research Aligns Numerical Simulations with Geological Evidence to Find Tsunamis Can Impact Small Inland Lakes

 

Using a multidisciplinary approach combining geological analysis and advanced numerical modeling, researchers from Khalifa University and the University of Savoy Mont Blanc have uncovered evidence of a previously unreported 12,000-year-old palaeo-tsunami event in Lake Aiguebelette, an alpine lake in France.

 

Since this tsunami was caused by an instability of underwater sediments in relation to a past earthquake, the study in particular shows that tsunami waves can happen even in small lakes, and that a major rock collapse is not always necessary to trigger such an event.

 

The findings, published in the Journal of Geophysical Research – Solid Earth (Wiley), titled ‘Numerical Reconstruction of Landslide Paleotsunami using Geological Records in Alpine Lake Aiguebelette’ detail the reconstruction of this ancient tsunami event and challenge conventional assumptions about the causes and behavior of tsunamis. The research team includes Dr. Denys Dutykh, Associate Professor, Mathematics, Khalifa University; Muhammad Naveed Zafar, PhD Researcher, and Dr. Pierre Sabatier, Lecturer, Earth Sciences, University of Savoy. 

 

The team’s numerical simulations, which closely matched the available geological data, revealed that the palaeo-tsunami took place approximately 11,700 years ago, enabling the detection of traces of the event in deep sedimentary layers. A mathematical modeling of the paleo underwater landslide, which indicates a significant paleo-tsunami event, also provided valuable insights into the risks of landslide-induced tsunamis in mountainous regions.

By aligning computer simulations with the actual geological evidence, the researchers determined that wave dispersion played a relatively minor role in this particular lacustrine (lake-based) tsunami event, highlighting how tsunamis can also occur and impact small inland bodies of water.

 

Several advanced techniques were used to study the lake and gather data about the event, including identifying the initial area where the event originated. By acquiring highly detailed bathymetric data, which provided very accurate measurements of the lake’s depth, they also used seismic profiling and core sediment to create and characterize the mass wasting deposit in the lake sediment. Building on this geological fieldwork data, researchers conducted complex computer modeling and simulations. Mathematical models were used to simulate the underwater landslide and the resulting tsunami. The depth-averaged visco-plastic Herschel-Bulkley rheological model, known as BingClaw, was employed for the landslide simulation. For the tsunami, both the depth-averaged nonlinear shallow water equations (NSWE) model, GeoClaw, and the dispersive tsunami model, BoussClaw, were utilized. 

 

Dr. Denys Dutykh said: “Researching palaeo-tsunamis is crucial due to the long recurrence intervals of these events. This multidisciplinary research not only enhances our understanding of tsunamis in small lacustrine settings, but also lays the groundwork for future investigations in other lakes and coastal areas. The contribution of both mathematicians and the geologists were crucial. Without the successful reconstruction of the event using geological and numerical studies, this work would not have been accepted for publication in such a prestigious journal.” 

 

The team plans to expand their studies to additional lakes and conduct onshore tsunami deposit surveys at Lake Aiguebelette to further refine their understanding of this ancient palaeo-tsunami event.

 

Alisha Roy
Science Writer
4 June 2024

Study from the Global Burden of Disease Collaborator Network, including Khalifa University’s Dr. Wael Osman, tracks the global shifts in cardiovascular health over decades of heart health research.

 

Cardiovascular disease (CVD) remains the world’s number one killer, but a comprehensive study spanning over three decades shows both progress and persistent challenges in the global fight against heart disease. The study was conducted by an extensive collaborative team of researchers from around the world, including Khalifa University’s Dr. Wael Osman, Assistant Professor of Biological Sciences. One of many such studies by the Global Burden of Disease Collaborator Network, the investigation examines the trends and impacts of cardiovascular diseases globally from 1990 to 2022.

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The global study with the Global Burden of Disease Collaborator Network, which includes more than 700 investigators worldwide, estimated the CVD burden for 204 countries and territories. The results were published in the Journal of the American College of Cardiology, a top 1% journal.

 

The study shows that significant strides in reducing CVD mortality rates are tempered by the uneven distribution of progress. While, globally, CVD mortality has decreased by 34.9 percent since 1990, region disparities are stark: High-income Asia Pacific countries saw the lowest age-standardized CVD mortality rate in 2022, at 73.6 per 100,000 people, while Eastern Europe reported a rate of 432.3 per 100,000.

 

“The cardiovascular disease epidemic is a significant global health challenge, causing heart attacks, strokes, and other complications that greatly affect mortality and morbidity rates,” the researchers say. “In this study, countries and territories are categorized into different regions to give a comprehensive perspective. Eighteen cardiovascular conditions and 15 prominent risk factors were assessed across three categories, including environmental, metabolic and behavioral factors.”

 

Ischemic heart disease, also known as coronary heart disease, and stroke remain the leading causes of CVD deaths, emphasizing the continued need for robust healthcare systems and effective public health strategies.

 

“As the disease results in a substantial number of premature deaths and preventable deaths, preventative measures and effective management strategies are essential,” the study says. “Considering the aging population and rapid urbanization of contemporary societies, this underscores the necessity for increased awareness and action through targeted public health measures.”

 

The study also highlights the impact of various risk factors on CVD rates. High systolic blood pressure is identified as the leading risk factor for CVD globally, contributing to the highest number of disability-adjusted life years (DALYs), a measure of overall disease burden. On the other hand, household air pollution from solid fuels, a significant risk factor in lower-income regions, saw the largest decrease in attributable DALYs, dropping by 65.1 percent since 1990.

 

While the reduction in global CVD mortality rates is encouraging, the persistent high rates in regions like Eastern Europe and Central Asia point to an ongoing need for targeted health interventions and policies. For example, Central Asia saw a 16.5 percent decrease in mortality, compared to Australasia’s 65.5 percent reduction. The overall global decline in CVD deaths demonstrates the potential benefits of improved healthcare access and advancements in medical technology, alongside the changes brought by policy shifts in diet, exercise and smoking habits.

 

This extensive study not only sheds light on the progress made but also underscores the work that remains. With continued international collaboration and commitment, further strides can be made towards a healthier global population. 

 

Jade Sterling
Science Writer
27 May 2024

Interpenetrating phase composites represent a new frontier in materials science, offering substantial improvements in mechanical and functional properties through innovative design and manufacturing techniques. 

 

 

As the realm of materials science continues to evolve, interpenetrating phase composites (IPCs) are emerging as a pivotal area of innovation, particularly in metal-metal and polymer-metal combinations. Prof. Wael Zaki and Ahmed Asar from Khalifa University’s Department of Mechanical Engineering and Advanced Digital and Additive Manufacturing Group, reviewed the crucial role of synergistic interactions within IPCs, where the mechanical properties such as strength and damage tolerance are significantly enhanced beyond what traditional composite theories would predict. Their review was published in Composites Part B, a top 1% journal.

 

IPCs are defined by their unique architectural arrangement where two or more interconnected, interlocking phases create a continuous structure. This significantly enhances the composite’s overall mechanical and functional properties while also preserving the integrity and load-bearing capacity of each constituent phase. Each phase refers to a distinctly different material or class of solid (polymer, metal or ceramic, for example) within the composite, with each phase retaining its separate chemical and physical identity.

 

By interlocking different phases with complementary properties, IPCs can achieve performance characteristics that are not possible with any single material or traditional composites where one material is embedded within another without forming a continuous network.

 

“IPCs take on many forms and may be composed of materials within the same or different material classes, but the common defining feature in all IPCs is the mechanical interlocking and interface continuity in all directions,” Asar explains. “IPCs have very strong potential to produce excellent functional composites for general and highly specialized applications.”

 

Initially centered on ceramic-based systems, research on IPCs has shifted towards polymer and metal-based variants over the last decade. This transition is largely fueled by the advent of additive manufacturing techniques, which have opened new avenues for exploring different phase combinations and designs in IPCs.

 

The researchers note that IPCs incorporating copper and gold maintain their electrical and thermal conductivities, while those with magnesium have improved high temperature damping properties, with the second phase compensating loss of magnesium mechanical properties under these conditions. However, magnesium is also biodegradable and could be used in partially degradable orthopedic implants. Using materials such as Nitinol can offer shape memory properties, which could be transformative for many engineering applications.

 

With all the advancements, the researchers also identify several challenges, including the need for better integration of different IPCs and enhancing the interface quality between the phases. Addressing these issues is essential for harnessing their full potential in practical applications. The researchers emphasize the importance of continued research into the field, particularly in exploring new material combinations through innovative manufacturing techniques.

 

“The goal is to pave the way for the next generation of IPCs that are not only more efficient and durable but also tailored for specific applications in industries ranging from aerospace to biomedicine,” Asar says. 

 

Jade Sterling
Science Writer
27 May 2024

Innovative techniques harness the sun and mimic nature’s ingenuity for efficient desalination

 

Amidst growing global concerns about water scarcity and the environmental impact of traditional desalination methods, a team of researchers at Khalifa University has investigated the intricate mechanism of halophyte plants, invented a mangrove-mimicked solar distillation device, presenting a comprehensive model that integrates capillary pumping and evaporation processes for passive solar desalination. Prof. TieJun Zhang led the team on both projects, comprising Muhammad Sajjad, Mohamed Abdelsalam, Dr. Aikifa Raza and Dr. Faisal AlMarzooqi.

 

Their device not only efficiently produces fresh water from seawater but also manages brine without discharging it into the environment, addressing significant ecological issues associated with salt buildup in natural water bodies. These results were published in Nature Communications.

 

The “Freshwater Generator” was designed to mimic the natural water management of mangroves, using a foldable structure with “leaves” and “stems” made from a titanium mesh covered with nanostructured titanium dioxide. This design enhances sunlight absorption and water transport, maximizing the efficiency of solar distillation. The mangrove-like structure supports passive, capillary-driven water transport and selective salt crystallization at the leaf edges, which prevents salt accumulation on the main evaporative surface and maintains high operational efficiency.

 

The team proposed a novel capillary transport model that precisely describes the passive saline water supply through synthetic porous wicks and evaporation at the synthetic leaf designed for solar desalination. Understanding wicking behavior with varying water saturation levels across the porous synthetic stem is crucial for enhancing our understanding of how saline water is pumped up against gravity without external driving force and evaporates in synthetic and real mangroves. These results were published in the International Journal of Heat and Mass Transfer.

 

The insights gained from this study are invaluable for designing next-generation solar desalination systems and mark a significant step towards a sustainable future in water resource management.

 

The team’s freshwater generator achieves an efficiency of about 94 percent and can produce up to 2.2 liters/m2 of fresh water per day from seawater. Its efficiency stems from its design, allowing for continuous operation by naturally shedding salt buildup overnight, preparing the system for operation the next day without manual cleaning. Overall, the simple design and portable nature of their solar-driven freshwater generator can provide a viable solution to produce clean water in remote areas. Using solar energy for passive desalination actually eliminates both the carbon footprint and pumping costs, and the zero-brine discharge with salt collection also prevents potential ecological damage typically associated with high-salinity waste from traditional desalination plants. 

 

Jade Sterling
Science Writer
27 May 2024

Carbon nanotubes are transforming 3D-printed buildings by strengthening the concrete

 

In the evolving landscape of construction technology, the fusion of carbon nanotubes with 3D-printed cement materials is setting new benchmarks in structure integrity and efficiency. Dr. Tae Yeon Kim, Mohd Mukarram Ali, Ghaith Nassrullah, Prof. Rashid Abu Al-Rub and Dr. Bashar El-Khasawneh, with Seyed Hamidreza Ghaffar from University of Birmingham, studied this combinations, revealing how carbon nanotubes significantly enhance both the mechanical properties and printing quality of 3D-printed buildings. Their results were published in Developments in the Built Environment, a top 1% journal.

 

“Traditionally, 3D printing cementitious materials poses certain challenges, involving a careful balance of printability, buildability, and the rheology of the mixture,” Dr. Kim explains. “Incorporating nanomaterials into 3D-printed cements is expected to minimize the setting time, limit pores and voids, reduce drying shrinkage, improve printing quality, and enhance the mechanical properties of the material.”

 

Carbon nanotubes are known for their robustness and flexibility, exhibiting high mechanical strength, resistance to oxidation and corrosion, high conductivity, and thermal properties. They form nanoscale bridges within the cement matrix, which effectively distribute stress and mitigate the formation of micro cracks, enhancing the durability and longevity of structures.

 

The researchers showed that adding carbon nanotubes to the 3D printing process not only improved the printability of the cement but also considerably strengthened the resulting structures: A mix containing just 0.2 percent carbon nanotubes led to a 99 percent increase in flexural strength and a 72 percent increase in compressive strength once the cement had cured for 28 days.

 

Including carbon nanotubes also optimizes the printing process itself. The researchers found that their mix ensured a smoother flow through the printer nozzles, resulting in more uniform and structurally sound layers.

 

These findings offer a promising future for 3D-printed structures in the construction industry, where speed, cost-efficiency, and structural integrity are paramount. 

 

Jade Sterling
Science Writer
27 May 2024

Research explores the immune compatibility of 2D nanomaterials in biomedical applications to harness full potential of nanotechnology in medicine

 

A recent study from a team of researchers led by Khalifa University’s Dr. Lucia Gemma Delogu, Associate Professor, provides fascinating insights into the interaction of nanomaterials with the immune system. The study focused on two-dimensional transition metal dichalcogenides (TMDs), specifically molybdenum disulfide (MOS2) and tungsten disulfide (WS2), to shed light on the biocompatibility and immunological effects of the two nanomaterials. The work was the result of multidisciplinary efforts with investigators from Manchester University, the Karolinska Institute, Augusta University, and the University of Padua. The findings were published in Nano Today.

 

TMDs have garnered significant research interest due to their unique physicochemical properties, including a combination of electrical, mechanical, and optical characteristics, which make them suitable for applications including drug delivery, tissue engineering, and bioimaging. Understanding their interactions with the immune system is crucial for assessing their safety and efficacy in biomedical applications.

 

“Immune cell interactions are pivotal in driving future TMD applications,” Dr. Delogu says. “They have demonstrated promising applications in photothermal therapy, for example, as they interact with immune cells in tumors. In lab settings, they can directly trigger host immunity by activating specific cells and even reduce the spread of cancer. However, we need to understand the complex interactions between TMDs and human cells to advance their use in biomedicine.”

 

The research team investigated the impact of MOS2 and WS2 on 16 immune cell types using innovative analytical techniques for the label-free detection of TMDs within immune cells and tissues. Traditional approaches often require individual bioassay molecules to be labeled for detection using another molecule: Identify that molecule in a cell and it can be assumed that the target molecule was also identified. However, some of these labeling molecules can alter the biological function of the nanomaterials and skew experimental results.   

 

“We used single-cell mass cytometry by time-of-flight, or CyTOF, which can detect metal element-tagged antibodies based on their mass/charge ratio.” Dr. Delogu explained.

 

By transforming the classical approaches, using CyTOF allowed the team to confirm the physical presence of TMDs in biological systems and to develop a detailed understanding of their distribution and interaction with various immune cell types. These insights are invaluable for designing nanomaterials that can effectively target specific cells or tissues without eliciting unwanted immune reactions.

 

“A critical aspect of expanding the biomedical applications of nanomaterials is their detection in cells and tissues,” Dr. Delogu says. “Having established their biocompatibility, we needed to find out whether detection technologies could be applied to TMDs in in vivo studies. We injected mice with a mixture of the TMDs and both materials were easily detectable at the tissue level in all the cell populations we studied.”

 

The research team’s findings pave the way for further exploration of TMDs in biomedicine, including their potential as drug delivery systems, imaging agents, or components of tissue engineering structures. Their proven biocompatibility and the ability to monitor their interactions with the immune system could lead to safer and more effective biomedical applications.

 

“Novel nanotechnology solutions in biology and medicine are strongly required and can lead to new exciting scenarios,” Dr. Delogu says. 

 

Jade Sterling
Science Writer
27 May 2024