. Scientific Frontline: Engineering
Showing posts with label Engineering. Show all posts
Showing posts with label Engineering. Show all posts

Monday, February 26, 2024

A Novel Method for Easy and Quick Fabrication of Biomimetic Robots with Life-Like Movement


Ultraviolet-laser processing is a promising technique for developing intricate microstructures, enabling complex alignment of muscle cells, required for building life-like biohybrid actuators, as shown by Tokyo Tech researchers. Compared to traditional complex methods, this innovative technique enables easy and quick fabrication of microstructures with intricate patterns for achieving different muscle cell arrangements, paving the way for biohybrid actuators capable of complex, flexible movements.

Biomimetic robots, which mimic the movements and biological functions of living organisms, are a fascinating area of research that can not only lead to more efficient robots but also serve as a platform for understanding muscle biology. Among these, biohybrid actuators, made up of soft materials and muscular cells that can replicate the forces of actual muscles, have the potential to achieve life-like movements and functions, including self-healing, high efficiency, and high power-to-weight ratio, which have been difficult for traditional bulky robots that require heavy energy sources. One way to achieve these life-like movements is to arrange muscle cells in biohybrid actuators in an anisotropic manner. This involves aligning them in a specific pattern where they are oriented in different directions, like what is found in living organisms. While previous studies have reported biohybrid actuators with significant movement using this technique, they have mostly focused on anisotropically aligning muscle cells in a straight line, resulting in only simple motions, as opposed to the complex movement of native muscle tissues such as twisting, bending, and shrinking. Real muscle tissues have a complex arrangement of muscle cells, including curved and helical patterns.

Tuesday, February 20, 2024

Invasive weed could be turned into a viable economic crop

Prof Rahman and Dr Karim collecting paddy melons for urease enzyme extraction.
Photo Credit: Courtesy of University of South Australia

One of the most invasive Australian weeds is being touted as a potential economic crop, with benefits for the construction, mining and forestry industries, and potentially many First Nations communities.

The prickly paddy melon weed, which costs the agricultural industry around $100 million a year in lost grain yields, cattle deaths, and control measures, could turn into an unlikely money spinner as a source of urease enzymes to create bio cement and prevent soil erosion.

In a world-first study, researchers at the University of South Australia (UniSA) screened 50 native plants and weeds to find a cheaper and more environmentally friendly source for bulk producing of urease enzymes to strengthen soil.

Among the weeds tested, paddy melon ticked all the boxes and was almost as effective as soybean enzymes, which are more expensive and used primarily for food.

UniSA geotechnical engineer Professor Mizanur Rahman and his students collected the paddy melon weed from roadsides in Port Pirie in South Australia. After crushing the seeds and extracting enzymes in a liquid form, they freeze-dried them to create a powdered, high-concentration cementation agent.

Monday, February 19, 2024

Researcher receives Naval Research Laboratory grant to develop more sophisticated sensor array

From left to right, engineering faculty researchers Dongfang Liu, Xudong Zheng, and Qian Xue display the seal whisker specimen they are modeling their advanced sensor array on for improving underwater detection and recognition.
Photo Credit: Travis Lacoss/RIT

Researchers at Rochester Institute of Technology are creating a novel sensor system based on the superior design and detection range found on harbor seal whiskers.

Xudong Zheng, an associate professor in RIT’s Kate Gleason College of Engineering, received a three-year, $746,000 award from the Naval Research Laboratory to build an autonomous underwater detection and tracking system with biological-level sensitivity, accuracy, and intelligence.

With demands for new sensor capabilities, increased sensitivity and accuracy could significantly advance underwater scientific explorations, such as tracking anomalies and seismic events in areas currently inaccessible or in improvements to robotic functions and military stealth missions.

“This is the next stage of development of stronger sensors,” said Zheng, whose team published findings in Frontiers in Robotics and AI. “Some early results of our computer simulations show that the sensor array combined with ‘smart’ algorithms could provide more smart perceptions and better reasoning regarding the signal pattern and how it corresponds to flow patterns.”

Thursday, February 15, 2024

Innovative materials to combat bacteria

Three bacteria from the ESKAPE group: Staphylococcus aureus (yellow), Pseudomonas aeruginosa (short thick blue rods) and Escherichia coli (long blue rods).
Image Credit: © UNIGE

While crucial to biotechnology, bacteria can also cause severe disease, exacerbated by their increasing resistance to antibiotics. This duality between economic benefits and infectious risks underlines the importance of finding ways to control their development. A team at the University of Geneva (UNIGE) is currently developing a new generation of bactericidal alloys, with a wide range of industrial applications. They could be used to treat the contact surfaces responsible for their transmission. The project, which is supported by Innosuisse, will take 18 months to complete.

Resistance to antimicrobial drugs - such as antibiotics and antivirals - is a global public health issue. According to the World Health Organization (WHO), it is currently responsible for 700,000 deaths a year worldwide. If no action is taken, the number of deaths will rise to 10 million a year by 2050, with dramatic consequences for public health and the economy.

To promote and guide research in this field, the WHO has published a list of pathogens that should be targeted as a matter of priority, because they are particularly threatening to human health. The list includes Staphylococcus aureus and E. coli bacteria, which are associated with the most common hospital-acquired infections, as well as salmonella. Contaminated contact surfaces (utensils, handles, stair railings) play a fundamental role in their transmission.

Wednesday, February 14, 2024

New Algorithm Disentangles Intrinsic Brain Patterns from Sensory Inputs

Image Credit: Omid Sani, Using Generative Ai

Maryam Shanechi, Dean’s Professor of Electrical and Computer Engineering and founding director of the USC Center for Neurotechnology, and her team have developed a new machine learning method that reveals surprisingly consistent intrinsic brain patterns across different subjects by disentangling these patterns from the effect of visual inputs.

The work has been published in the Proceedings of the National Academy of Sciences (PNAS).

When performing various everyday movement behaviors, such as reaching for a book, our brain has to take in information, often in the form of visual input — for example, seeing where the book is. Our brain then has to process this information internally to coordinate the activity of our muscles and perform the movement. But how do millions of neurons in our brain perform such a task? Answering this question requires studying the neurons’ collective activity patterns, but doing so while disentangling the effect of input from the neurons’ intrinsic (aka internal) processes, whether movement-relevant or not.

That’s what Shanechi, her PhD student Parsa Vahidi, and a research associate in her lab, Omid Sani, did by developing a new machine-learning method that models neural activity while considering both movement behavior and sensory input.

Monday, December 25, 2023

Blue PHOLEDs: Final color of efficient OLEDs finally viable in lighting

Jaesang Lee, Electrical Engineering PhD Student, demonstrates use of an earlier blue PHOLED innovation by University of Michigan professor Steve Forrest’s research group in 2014. Forrest’s lab introduced PHOLEDs to the world in the early 2000s and has been trying to improve the lifetime of blue PHOLEDs ever since. Now, they might finally be hardy enough to use in lighting applications. Image credit: Joseph Xu, Michigan Engineering Communications & Marketing The blue LEDs were developed in EECS Professor Stephen Forrest’s lab groups and are for use in cell phones, tablets, and other electronics. The LEDs’ lifetime has been enhanced by a factor of ten, allowing for more efficient use.
Photo Credit: Joseph Xu, Michigan Engineering Communications & Marketing

Lights could soon use the full color suite of perfectly efficient organic light-emitting diodes, or OLEDs, that last tens of thousands of hours, thanks to an innovation from physicists and engineers at the University of Michigan.

The U-M team’s new phosphorescent OLEDs, commonly referred to as PHOLEDs, can maintain 90% of the blue light intensity for 10-14 times longer than other designs that emit similar deep blue colors. That kind of lifespan could finally make blue PHOLEDs hardy enough to be commercially viable in lights that meet the Department of Energy’s 50,000-hour lifetime target. Without a stable blue PHOLED, OLED lights need to use less-efficient technology to create white light.

The lifetime of the new blue PHOLEDs currently is only long enough to use as lighting, but the same design principle could be combined with other light-emitting materials to create blue PHOLEDs hardy enough for TVs, phone screens and computer monitors. Display screens with blue PHOLEDs could potentially increase a device’s battery life by 30%.

Shock wave photographed passing through a single cell

Images of an underwater shock wave moving through a HeLa cell.
Using this new technology, the researchers could see the difference between how the shock wave moved inside and outside of a cell submerged in water. They noted that the results suggested that the cell structure shifts with the visualized wavefront position (shown in the red/ orange line in the image).
 Image Credit: © 2023 Saiki et al. University of Tokyo

A microscopic shock wave has been photographed passing through a single biological cell, thanks to a new photography technique. Nanosecond photography uses ultrafast electronic cameras to take images at the speed of a billionth of a second. However, image quality and exposure time are typically limited. Now, a team led by researchers at the University of Tokyo has achieved superfine images taken over multiple timescales at high-speed using a system they named spectrum circuit. Spectrum circuit bridges the gap between optical imaging and conventional electronic cameras, enabling photography at ultrafast speeds with less blur and more accuracy. This technology has potential applications for science, medicine and industry.

You’re waiting with your camera for just the right moment. Suddenly, your subject speeds by and you’ve barely clicked the shutter. Missed it. Timing can be everything in photography and capturing images at high speed poses a particular challenge. But thanks to advances in camera technology, these days we can see the world like never before. Whether it’s the sweat on a racing cyclist’s brow, the focus in the eyes of a swooping falcon or, with this latest improvement in nanosecond photography, the movement of a shock wave passing through a microscopic single cell at high speed.

Thursday, December 21, 2023

Novel Catalyst System for CO2 Conversion

Kevinjeorjios Pellumbi with the experimental setup for CO2 conversion
Photo Credit: © RUB, Marquard

Researchers are constantly pushing the limits of technology by breaking new ground in CO2 conversion. Their goal is to turn the harmful greenhouse gas into a valuable resource.

Research groups around the world are developing technologies to convert carbon dioxide (CO2) into raw materials for industrial applications. Most experiments under industrially relevant conditions have been carried out with heterogeneous electrocatalysts, i.e. catalysts that are in a different chemical phase to the reacting substances. However, homogeneous catalysts, which are in the same phase as the reactants, are generally considered to be more efficient and selective. To date, there haven’t been any set-ups where homogeneous catalysts could be tested under industrial conditions. A team headed by Kevinjeorjios Pellumbi and Professor Ulf-Peter Apfel from Ruhr University Bochum and the Fraunhofer Institute for Environmental, Safety and Energy Technology UMSICHT in Oberhausen has now closed this gap. The researchers outlined their findings in the journal Cell Reports Physical Science.

“Our work aims to push the boundaries of technology in order to establish an efficient solution for CO2 conversion that will transform the climate-damaging gas into a useful resource,” says Ulf-Peter Apfel. His group collaborated with the team led by Professor Wolfgang Schöfberger from the Johannes Kepler University Linz and researchers from the Fritz Haber Institute in Berlin.

New brain-like transistor mimics human intelligence

An artistic interpretation of brain-like computing.
Illustration Credit: Xiaodong Yan/Northwestern University

Taking inspiration from the human brain, researchers have developed a new synaptic transistor capable of higher-level thinking.

Designed by researchers at Northwestern University, Boston College and the Massachusetts Institute of Technology (MIT), the device simultaneously processes and stores information just like the human brain. In new experiments, the researchers demonstrated that the transistor goes beyond simple machine-learning tasks to categorize data and is capable of performing associative learning.

Although previous studies have leveraged similar strategies to develop brain-like computing devices, those transistors cannot function outside cryogenic temperatures. The new device, by contrast, is stable at room temperatures. It also operates at fast speeds, consumes very little energy and retains stored information even when power is removed, making it ideal for real-world applications.

“The brain has a fundamentally different architecture than a digital computer,” said Northwestern’s Mark C. Hersam, who co-led the research. “In a digital computer, data moves back and forth between a microprocessor and memory, which consumes a lot of energy and creates a bottleneck when attempting to perform multiple tasks at the same time. On the other hand, in the brain, memory and information processing are co-located and fully integrated, resulting in orders of magnitude higher energy efficiency. Our synaptic transistor similarly achieves concurrent memory and information processing functionality to more faithfully mimic the brain.”

Wednesday, December 20, 2023

RIT researchers develop new technique to study how cancer cells move

Vinay Abhyankar, right, assistant professor of biomedical engineering, works closely with two doctoral students, Mehran Mansouri, left, and Indranil Joshi, on research to assess cancer cell migration processes.
Photo Credit: A. Sue Weisler/RIT

In tumors, cells follow microscopic fibers, comparable to following roads through a city. Researchers at the Rochester Institute of Technology developed a new technique to study different features of these “fiber highways” to provide new insights into how cells move efficiently through the tumor environment.

The study, published in the journal Advanced Functional Materials, focused on contact guidance, a process where migrating cells follow aligned collagen fibers. Understanding this process is crucial, as it plays a key role in cancer metastasis, the spread of cancer to other parts of the body.

“Previous research on contact guidance, a process where cancer cells migrate along aligned collagen fibers, has been largely studied in collagen gels with uniform fiber alignment,” said Vinay Abhyankar, associate professor of biomedical engineering in RIT’s Kate Gleason College of Engineering, and study co-author. “However, the tumor microenvironment also features subtle variations or gradients in fiber alignment, and their role in cell migration has been largely unexplored. We suspected that alignment gradients could efficiently direct cell movement but lacked the technology to test the hypothesis.”

Tuesday, December 19, 2023

Researchers Find They Can Stop Degradation of Promising Solar Cell Materials

An illustration of metal halide perovskites. They are a promising material for turning light into energy because they are highly efficient, but they also are unstable. Georgia Tech engineers showed in a new study that both water and oxygen are required for perovskites to degrade. The team stopped the transformation with a thin layer of another molecule that repelled water.
Image Credit: Courtesy of Juan-Pablo Correa-Baena

Georgia Tech materials engineers have unraveled the mechanism that causes degradation of a promising new material for solar cells — and they’ve been able to stop it using a thin layer of molecules that repels water.

Their findings are the first step in solving one of the key limitations of metal halide perovskites, which are already as efficient as the best silicon-based solar cells at capturing light and converting it into electricity. They reported their work in the Journal of the American Chemical Society.

“Perovskites have the potential of not only transforming how we produce solar energy, but also how we make semiconductors for other types of applications like LEDs or phototransistors. We can think about them for applications in quantum information technology, such as light emission for quantum communication,” said Juan-Pablo Correa-Baena, assistant professor in the School of Materials Science and Engineering and the study’s senior author. “These materials have impressive properties that are very promising.”

Thursday, December 14, 2023

Researchers Find Way to Weld Metal Foam Without Melting Its Bubbles

Composite metal foam (CMF) components
Image Credit: Courtesy of North Carolina State University

Researchers at North Carolina State University have now identified a welding technique that can be used to join composite metal foam (CMF) components together without impairing the properties that make CMF desirable. CMFs hold promise for a wide array of applications because the pockets of air they contain make them light, strong and effective at insulating against high temperatures.

CMFs are foams that consist of hollow, metallic spheres – made of materials such as stainless steel or titanium – embedded in a metallic matrix made of steel, titanium, aluminum or other metallic alloys. The resulting material is both lightweight and remarkably strong, with potential applications ranging from aircraft wings to vehicle armor and body armor.

In addition, CMF is better at insulating against high heat than conventional metals and alloys, such as steel. The combination of weight, strength and thermal insulation means that CMF also holds promise for use in storing and transporting nuclear material, hazardous materials, explosives and other heat-sensitive materials.

However, in order to realize many of these applications, manufacturers would need to weld multiple CMF components together. And that has posed a problem.

Wednesday, December 13, 2023

The 'one-pot' nanosheet method catalyzing a green energy revolution

Illustration Credit: Minoru Osada

A research group from the Institute for Future Materials and Systems at Nagoya University in Japan has developed a new “one-pot” method to make nanosheets using less rare metals. Their discovery should allow for the energy-making process to be more eco-friendly. The journal ACS Nano published the study.

Producing clean energy is important because it helps reduce global warming and contributes to building a carbon-neutral society. A potential source of clean energy uses hydrogen catalysts, such as palladium (Pd). Industries use Pd in electrolysis to separate water into hydrogen and oxygen. Afterward, the hydrogen in fuel cells is used to create electricity. The only byproduct is water. 

Pd is commonly used in a spherical ‘nanoparticle’ form for catalyst use. However, a flatter, thinner surface would use fewer precious metals and increase the available surface area for the reaction.

Minoru Osada at Nagoya University and his research group have developed a new way to make Pd nanosheets. They named it the "one-pot method" because it can be done in a single glass bottle. The resulting sheets were so thin (1~2 nm) that they can be compared to the size of a single molecule or DNA strand.

Tuesday, December 12, 2023

Understudied cell in the brain could be key to treating glioblastoma

Perivascular fibroblasts observed in the study
Image Credit: Courtesy of the researcher / University of Notre Dame

Glioblastoma is one of the most treatment-resistant cancers, with those diagnosed surviving for less than two years.

In a new study in NPJ Genomic Medicine, researchers at the University of Notre Dame have found that a largely understudied cell could offer new insight into how aggressive, primary brain cancer is able to resist immunotherapy.

“A decade ago, we didn’t even know perivascular fibroblasts existed within the brain, and not just in the lining of the skull,” said Meenal Datta, assistant professor of aerospace and mechanical engineering at Notre Dame and senior author on the study. “My lab’s expertise is examining tumors from an engineering and systems-based approach and looking at the novel mechanical features in rare cancers that may have been understudied or overlooked.”

Using standard bioinformatics and newer AI-based approaches, Datta’s TIME Lab began analyzing different genes expressed in the tumor microenvironment related to the extracellular matrix — or the scaffolding cells create to support future cell adhesion, migration, proliferation and differentiation — and other various cell types. What they found was a surprising, fairly new cell type: perivascular fibroblasts. These fibroblasts are typically found in the blood vessels of a healthy brain and deposit collagen to maintain the structural integrity and functionality of brain vessels.

Tuesday, November 7, 2023

World’s first smart breathing tube for mechanically ventilated patients set for human trials

Professor Steve Morgan
Photo Credit: Courtesy of University of Nottingham

The University of Nottingham has secured £1.1 million in funding from the Medical Research Council to undertake human trials for the world’s first optical fiber sensor-equipped endotracheal tube (iTraXS).

Seriously ill or anaesthetized patients are unable to breathe naturally, so clinicians often use endotracheal tubes (ETTs), which are placed in the trachea (windpipe) to maintain an open airway and allow the patient to breathe through a mechanical ventilator. To do this, the tube is placed into the airway and a cuff (balloon) is inflated at the trachea to create a gas seal that allows air to be delivered to the lungs effectively. However, incorrect cuff inflation pressure can cause two main problems.

If pressure is too low, it can risk fluid getting past the cuff and causing ventilator-associate pneumonia (VAP). VAP increases the likelihood of death, affecting up to 20% of people in intensive care, and costs the NHS between £10,000 and £20,000 per patient. Conversely, if pressure is too high it can cause a pressure injury in the trachea, ranging from moderate to severe sore throats through to permanent scarring and narrowing of the windpipe.

Monday, October 30, 2023

To advance space colonization, WVU research explores 3D printing in microgravity

WVU engineering students and Microgravity Research Team members Renee Garneau, Trenton Morris and Ronan Butts test a 3D printer the MRT lab has designed to operate in weightless environments like a spaceship, the moon or Mars.
Photo Credit: Brian Persinger / West Virginia University

Research from West Virginia University students and faculty into how 3D printing works in a weightless environment aims to support long-term exploration and habitation on spaceships, the moon or Mars.

Extended missions in outer space require the manufacture of crucial materials and equipment onsite, rather than transporting those items from Earth. Members of the Microgravity Research Team said they believe 3D printing is the way to make that happen.

The team’s recent experiments focused on how a weightless microgravity environment affects 3D printing using titania foam, a material with potential applications ranging from UV blocking to water purification. ACS Applied Materials and Interfaces published their findings.

“A spacecraft can’t carry infinite resources, so you have to maintain and recycle what you have and 3D printing enables that,” said lead author Jacob Cordonier, a doctoral student in mechanical and aerospace engineering at the WVU Benjamin M. Statler College of Engineering and Mineral Resources. “You can print only what you need, reducing waste. Our study looked at whether a 3D-printed titanium dioxide foam could protect against ultraviolet radiation in outer space and purify water. 

Using lasers to ‘heat and beat’ 3D-printed steel could help reduce costs

Retrieval of a stainless steel part made by 3D printing 
Photo Credit: Jude E. Fronda

The method, developed by a research team led by the University of Cambridge, allows structural modifications to be ‘programmed’ into metal alloys during 3D printing, fine-tuning their properties without the ‘heating and beating’ process that’s been in use for thousands of years.

The new 3D printing method combines the best qualities of both worlds: the complex shapes that 3D printing makes possible, and the ability to engineer the structure and properties of metals that traditional methods allow. The results are reported in the journal Nature Communications.

3D printing has several advantages over other manufacturing methods. For example, it’s far easier to produce intricate shapes using 3D printing, and it uses far less material than traditional metal manufacturing methods, making it a more efficient process. However, it also has significant drawbacks.

“There’s a lot of promise around 3D printing, but it’s still not in wide use in industry, mostly because of high production costs,” said Dr Matteo Seita from Cambridge’s Department of Engineering, who led the research. “One of the main drivers of these costs is the amount of tweaking that materials need after production.”

Saturday, October 28, 2023

Mechanics of breast cancer metastasis discovered, offering target for treatment

A human breast cancer cell, adenocarcinoma MDA-MB-231, demonstrates metastatic-like adhesion, spreading and migrating in a collagen matrix designed to mimic soft tissue. New research led by Penn State reveals for the first time the mechanics behind how breast cancer cells may invade healthy tissues. The discovery, showing that a motor protein called dynein powers the movement of cancer cells in soft tissue models, offers new clinical targets against metastasis and has the potential to fundamentally change how cancer is treated. 
Image Credit: Erdem Tabdanov / Pennsylvania State University
(CC BY-NC-ND 4.0 DEED)

The most lethal feature of any cancer is metastasis, the spread of cancer cells throughout the body. New research led by Penn State reveals for the first time the mechanics behind how breast cancer cells may invade healthy tissues. The discovery, showing that a motor protein called dynein powers the movement of cancer cells in soft tissue models, offers new clinical targets against metastasis and has the potential to fundamentally change how cancer is treated.

“This discovery marks a paradigm shift in many ways,” said Erdem Tabdanov, assistant professor of pharmacology at Penn State and a lead co-corresponding author on the study, recently published in the journal Advanced Science. “Until now, dynein has never been caught in the business of providing the mechanical force for cancer cell motility, which is their ability to move themselves. Now we can see that if you target dynein, you could effectively stop motility of those cells and, therefore, stop metastatic dissemination.”

The project began as a collaboration between Penn State’s Department of Chemical Engineering and Penn State’s College of Medicine, before growing into a multi-institution partnership with researchers at the University of Rochester Medical Center, Georgia Institute of Technology, Emory University, and the U.S. Food and Drug Administration.

Binghamton computer scientists program robotic seeing-eye dog to guide the visually impaired

Associate Professor of Computer Science Shiqi Zhang and his students have programmed a robot guide dog to assist the visually impaired. The robot responds to tugs on its leash.
Photo Credit: Stephen Folkerts

Last year, the Computer Science Department at the Thomas J. Watson College of Engineering and Applied Science went trick-or-treating with a quadruped robotic dog. This year, they are using the robot for something that Assistant Professor Shiqi Zhang calls “much more important” than handing out candy, as fun as that can be.

Zhang and PhD students David DeFazio and Eisuke Hirota have been working on a robotic seeing-eye dog to increase accessibility for visually impaired people. They presented a demonstration in which the robot dog led a person around a lab hallway, confidently and carefully responding to directive input.

Zhang explained some of the reasons behind starting the project.

“We were surprised that throughout the visually impaired and blind communities, so few of them are able to use a real seeing-eye dog for their whole life. We checked the statistics, and only 2% of them are able to do that,” he said.

Thursday, October 26, 2023

Breakthrough synthesis method improves solar cell stability

Jin Hou is a Rice University graduate student and lead author on a study published in Nature Synthesis. Photo Credit: Courtesy of Jin Hou

Solar cell efficiency has soared in recent years due to light-harvesting materials like halide perovskites, but the ability to produce them reliably at scale continues to be a challenge.

A process developed by Rice University chemical and biomolecular engineer Aditya Mohite and collaborators at Northwestern University, the University of Pennsylvania and the University of Rennes yields 2D perovskite-based semiconductor layers of ideal thickness and purity by controlling the temperature and duration of the crystallization process.

Known as kinetically controlled space confinement, the process could help improve the stability and reduce the cost of halide perovskite-based emerging technologies like optoelectronics and photovoltaics.

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