As the population in U.S. urban communities continues to grow exponentially, so does the demand for appropriate housing and office space. Typically, in large urban areas this means building residential and commercial units that are up to 20 stories high, made with concrete or steel, as it has been done in the past century. Yet sometimes, these materials are not ideal in earthquake-prone areas.


A new timber structural innovation, known as cross laminated timber (CLT), is being implemented around the world as a sustainable alternative to conventional structural materials. In comparison to building with steel and concrete, timber outperforms in lightness, cost, speed of construction, and environmental impact. However, building tall with cross laminated timber has been limited in earthquake active regions, since a validated design method for tall CLT buildings to resist earthquakes has not yet been developed. Colorado School of Mines plans to change that, with the development of a resilience-based seismic design for tall timber construction.

Civil and Environmental Engineering Assistant Professor Shiling Pei aims to develop a seismic design methodology over the next four years for resilient tall wood buildings. “This project, scientifically, will answer a lot of questions we have regarding how to design [these buildings] and how to perfect their performance in earthquakes so that the buildings can be immediately reoccupied after a big earthquake,” said Pei, who is also the principal investigator on a $1.5 million award from the National Science Foundation (NSF) for the project, A Resilience-based Seismic Design Methodology for Tall Wood Buildings.

With six universities and multiple domestic and international industry partners collaborating on this project, researchers will design, build and validate the performance of a 10-story wood building by conducting a full-scale sub-assembly system testing at the Natural Hazards Engineering Research Infrastructure (NHERI) experimental facility at Lehigh University in Bethlehem, Penn. This will then be followed by a full-scale test at the NHERI outdoor shake table at the University of California at San Diego—the largest outdoor table in the world.

The model tested on the shake table will be an actual building designed to a resilience performance target, Pei explained, with everything from the finishing drywall to the windows. “This will be the largest building that has been tested on the shake table,” said Pei. But since this is a full-scale model and includes all building components, not just the structural framework, the project can get expensive.

In addition to the support from NSF, the research team still needs to raise approximately $800,000 in order to complete the project. They have already received interest from most industry leaders who see the benefits of their work, which would enable a new sustainable construction practice that is also cost-competitive. If successful, implementing the design method would increase the demand for engineered wood production, providing added value for forest resources and enhancing job growth in construction and forestry sectors.

The researchers expect to have all the designs and donations lined up by the end of 2019 with building anticipated to begin in 2020. “We are excited about the new data this landmark experiment will generate,” said Pei. “It could have an enormous impact on the tall timber building industry, and lead to new building practices using more sustainable materials.”



Ashley Spurgeon, Editorial Assistant, Mines Magazine | 303-273-3959 |
Deirdre Keating, Communications Manager, College of Engineering & Computational Sciences | 303-384-2358 |

ADAPT team members and the governor celebrate the new proclamation.

ADAPT team members celebrate the Governor's proclamation, naming October Colorado Manufacturing Month.
Left to right: Aaron Stebner, Katie Woslager, Governor John Hickenlooper, Brandan Kappes, Mickele Bragg, Sumer Sorensen-Bain,
Heidi Hostetter, Craig Brice, Alicia Svaldi and Douglas Van Bossuyt.

Colorado School of Mines and Manufacturer’s Edge hosted Governor John Hickenlooper on September 30 to tour the Alliance for the Development of Additive Processing Technologies (ADAPT) advanced characterization center and meet with the center's founding stakeholders. The governor also used the occasion to announce October as Manufacturing Month in Colorado.

ADAPT is a consortium that provides manufacturers access to the latest research on how to take advantage of additive manufacturing technologies. In addition to Mines and Manufacturer's Edge, ADAPT's founding stakeholders include Lockheed Martin, Ball Aerospace, and Fauston Tool. ADAPT companies work closely with Mines researchers and students on world-class machines to develop technologies to accelerate certification and qualification of 3-D printed metal parts. 

Governor Hickenlooper toured the facility and met with manufacturing leaders to discuss the growth of the sector and the role of the Colorado Office of Economic Development and International Trade’s (OEDIT) Advanced Industry Infrastructure grant program. ADAPT was started with support from the State of Colorado in the form of an Advanced Industries Infrastructure Grant from OEDIT.

”Colorado is home to 6,000 manufacturers that contribute $20 billion to the state’s economy. ADAPT is consistent with Colorado’s collaborative culture,” said Governor Hickenlooper. “It provides our entrepreneurial manufacturers the ability to work closely with university researchers to develop the next generation of technologies.”

“Innovation is the key to survival and growth for small and medium manufacturers,” said Heidi Hostetter, vice-president at Arvada-based Faustson Tool. “Through ADAPT, manufacturers of all sizes looking to incorporate the flexibility of 3-D metal printing into their portfolio will have access to cutting-edge research and help shape the future of the industry.”

Gov. Hickenlooper listens as Research Associate Professor Branden Kappes describes the work of ADAPT.

This tour kicked off Manufacturing DayTM celebrations in Colorado, which continue throughout the month of October. Manufacturing Day is an annual celebration of modern manufacturing meant to inspire the next generation of manufacturers, including Mines students.

“In Colorado, one day is not enough to recognize our manufacturers— so we are declaring October ‘Colorado Manufacturing Month,’” said Governor Hickenlooper as he presented a proclamation during his visit.

As ADAPT continues its work, the consortium is actively seeking additional academic and industry partners. Analysis is underway on more than 5,000 specimens with respect to build geometry, power, speed, number of lasers used and more, to build a robust database.


The Alliance for the Development of Additive Processing Technologies (ADAPT) is a research and development organization dedicated to the creation of next-generation data informatics and advanced characterization technologies for additive manufacturing technologies. ADAPT uses these tools to help industry and government qualify, standardize, assess and optimize advanced manufacturing processes and parts. Several levels of membership to the ADAPT consortium are available. Founding industry members include Ball Aerospace & Technologies Corp., Faustson Tool, Lockheed Martin and Citrine Informatics. Grant funding from OEDIT was provided to Manufacturer’s Edge and The National Institute of Standards and Technology’s Hollings Manufacturing Extension Partnership. For more information, find ADAPT on the web, LinkedIn, Facebook or Twitter.

About Manufacturer’s Edge

Manufacturer’s Edge is a statewide manufacturing assistance center, partially funded by NIST’s Hollings Manufacturing Extension Partnership (MEP). Manufacturer’s Edge provides onsite technical assistance, coaching, training and consulting, as well as collaboration-focused industry programs and leveraging government, university and economic development partnerships to boost the competitiveness of Colorado manufacturers.



Aaron Stebner, Assistant Professor of Mechanical Engineering
ADAPT Technical Director 
ADAPT – Alliance for the Development of Additive Processing Technologies
(303) 273-3091

Sumer Sorensen-Bain, Chief of Programs and Operations
Manufacturer’s Edge

Colorado School of Mines Geology PhD student Sebastian Cardona was awarded the Stephen E. Laubach Structural Diagenesis Award during the Geological Society of America’s 2016 Annual Meeting, held September 25-28 in Denver.
Cardona after receiving the Laubach award, with advisor Lesli Wood.

Cardona after receiving the Laubach award, with advisor Lesli Wood.

Cardona represented Mines’ Department of Geology and Geological Engineering at the conference with Professor Lesli Wood, his advisor and lead of the Sedimentary Analogs Database and Research Consortium.

The award promotes research combining structural geology and diagenesis, highlighting the growing need to break down disciplinary boundaries between structural geology and sedimentary petrology.
Cardona’s research exemplifies this interdisciplinary focus by integrating different data sets and methodologies such as seismic, well log, outcrops and microscopic data. His goal is to use these multidisciplinary data sets to understand the sealing properties of mass transport deposits in deep water settings. 
“Sebastian is one of many great student researchers we have in the SAnD research program who capture the integrative nature of science here at Mines,” said Wood. “I am proud of his work and the recognition he has received.”
Agata Bogucka, Communications Manager, College of Earth Resource Sciences & Engineering | 303-384-2657 |
Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |

A view into a deep mining tunnel with tracks running down the middle.
Colorado School of Mines underground classroom, the Edgar Experimental Mine. Photo: Agata Bugucka

While the U.S. continues to look for new energy sources, our reliance on mining for rare minerals grows. Unfortunately, miners often work in dangerous environments where there is a risk of mine explosions, fire, poisonous gases and flooding in tunnels. Mine accidents have killed over 40,000 mine workers worldwide in the past decade.

Mine safety demands a scalable, low-cost solution to enable sensing, communication and tracking in underground mines to detect precursors to emergencies and to aid rescue efforts in the aftermath of an accident. In spite of requirements for data and voice communications in underground mining growing significantly, the high cost of deploying a safety infrastructure often leads to companies only meeting the minimum required safeguards.

The National Science Foundation awarded a three-year $750,000 grant to the project, “Enabling Smart Underground Mining with an Integrated Context-Aware Wireless Headshot photo of Qi Han, associate professor of Computer ScienceCyber-Physical Framework,” in order to solve this problem. About $338,000 will go to Colorado School of Mines researchers, led by Computer Science Associate Professor Qi Han, in collaboration with Carl Brackpool, a research associate in the Department of Mining Engineering. Han shares in the grant with fellow CS researchers at Colorado State University.

“I’ve been passionate about using my research expertise to improve mine safety for quite some time, so it’s very exciting that the NSF has chosen to support this research,” said Han. “I’m most interested in designing algorithms to support the co-existence of high quality voice streams in noisy underground environments. Providing voice streaming support will significantly improve situational awareness.”

The project will devise, design, prototype and test a fundamentally novel framework of low-cost, energy-efficient and reliable sensor nodes and commodity smartphones to improve safety in underground mines. The wireless cyber-physical framework would bypass GPS, cellular and other signals that we take for granted above ground.

The researchers will field-test their system in Colorado School of Mines’ Edgar Mine, used for research and education. They also will partner with Hecla Mining in Idaho, which has expressed interest in the proposed technology.

While useful for mining, the technology could lead to a host of other applications in the realm of next-generation smart workplaces and various “Internet of Things” applications. It could also be used in the aftermath of disasters for survivor rescue efforts.


Deirdre Keating, Communications Manager, College of Engineering & Computational Sciences | 303-384-2358 |
Ashley Spurgeon, Editorial Assistant, Mines magazine | 303-273-3959 |


Chemical and Biological Engineering Associate Professor Sumit Agarwal has been awarded $615,000 over four years by the U.S. Department of Energy SunShot Initiative to develop a scalable and more cost-effective method of manufacturing ultra-high-efficiency solar cells.

CBE Associate Professor Sumit Agarwal and postdoc Noemi LeickMost silicon-based solar cells in the market today have 16 to 18 percent efficiency, said Agarwal, while the maximum efficiency achieved in the lab is over 25 percent. “Our objective is to make it easier and cheaper to bridge this gap between the lab and industrial-scale devices,” he said.

Agarwal and his team, which includes postdoctoral researcher Noemi Leick and members of Silicon Photovoltaics project group at the National Renewable Energy Laboratory led by Paul Stradins, aim to fabricate solar cells with around 23 percent efficiency using their new method. The research will be performed both at Mines and NREL and will take advantage of NREL’s state-of-the-art deposition and new silicon device cleanroom facilities.

Mono-crystalline silicon (c-Si) solar cells provide the most promising pathway to electricity generation at costs that are comparable to conventional energy sources. Solar cells work by absorbing light and releasing separate positive and negative charges to create a current, and using c-Si minimizes the loss of energy from the recombination of these charges.

The efficiency of these cells is further improved by collecting both charges on the back side of the cell, as opposed to the traditional front-grid architecture, where metal contacts cover up some of the cell and prevent some light from being absorbed.

Diagram of solar cell with interdigitated back contacts.

Solar cells that use this design, however, only account for a small fraction of solar cells currently being manufactured, as they require the use of interdigitated back contacts, where the contact materials are arranged similarly to interlocked fingers. This requires a complex, repeated process where layers of material are added and sections of it are then removed.

Agarwal proposes to bypass these steps, using light and chemical vapor deposition to put down the material for the back contacts in the desired pattern. “Only the lit areas will get material growth,” Agarwal said. He believes this is a technique that can be translated into large-scale manufacturing.

In addition to the SunShot Initiative funding, the project will also receive a 10 percent match from Mines.


The grant is part of $107 million in new projects and planned funding announced by the Energy Department Sept. 14 to support clean energy innovation through solar technology. Under the SunShot Initiative, the department will fund 40 projects with a total of $42 million to improve PV performance, reliability, and manufacturability, and to enable greater market penetration for solar technologies.

In addition to the new projects, the department intends to make up to $65 million, subject to appropriation, in additional funding available for upcoming solar research and development projects to continue driving down the cost of solar energy and accelerating widespread national deployment. One of SunShot's goals is to drive down the levelized cost of utility-scale solar electricity to $0.06 per kilowatt-hour without incentives by 2020.

Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |
Ashley Spurgeon, Editorial Assistant, Mines magazine | 303-273-3959 |

Nuclear Engineering PhD student Michael ServisA PhD student in nuclear engineering has been awarded a prize in the Innovations in Fuel Cycle Research Awards, sponsored by the Department of Energy Office of Fuel Cycle Technologies.

Michael Servis’ award-winning research paper, “A Molecular Dynamics Study of Tributyl Phosphate and Diamyl Amyl Phosphonate Self-Aggregation in Dodecane and Octane,” was published in the Journal of Physical Chemistry in February 2016.

The awards program is designed to recognize graduate and undergraduate students for innovative research publications relevant to the nuclear fuel cycle, demonstrate the Department of Energy’s commitment to higher education in fuel cycle-relevant disciplines, and support communication between students and DOE representatives.

The program awarded 17 prizes in 2016. Servis, advised by Chemistry Assistant Professor Jenifer Braley and Chemistry Professor David Wu, was a winner in the competition for students who attend universities with less than $600 million in research and development expenditures in 2014.

Winners receive cash prizes, as well as travel and conference opportunities.

Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |
Deirdre Keating, Communications Manager, College of Engineering & Computational Sciences | 303-384-2358 |

Seventy-five students from across the country and around the world gathered at Mines this past July for the first graduate student summer school on thermoelectrics in the United States in two decades.

International Summer School on Thermoelectrics group photoPhysics Assistant Professor Eric Toberer organized the International Summer School on Thermoelectrics, which took place July 25 to 27, with Alexandra Zevalkink, assistant professor at Michigan State University. Funding came from the Mines Office of Technology Transfer and the National Renewable Energy Laboratory.

“Our objective was to provide an opportunity for students to develop new collaborations and to hear from leaders in the field about the current state of the art and fundamentals,” Toberer said. “Breakout discussions were a big part of this conference, largely as a forum to have graduate students interact with each other and gain insight from experts.”

Topics ranged from the physics of thermoelectric materials to materials synthesis, to practical module design. Speakers included scientists from NREL, Northwestern University, Georgia Tech, Duke University and Stanford Synchrotron Radiation Lightsource.

Attendees came from the U.S., Switzerland, South Korea, Japan, India and Spain. “We had a 100 percent acceptance policy for graduate students in thermoelectric research groups,” Toberer said. Several undergraduate Mines students who have been conducting research in thermoelectrics also took part. “The summer school paid for lodging, food and registration; the students simply had to arrive,” Toberer said.

Brenden Ortiz, a Mines PhD student, received the Journal of Materials Chemistry A poster award for best overall presentation.

The organizers hope to collaborate with the International Thermoelectric Society for next year’s summer school and hold it in conjunction with their national meeting in Los Angeles. “After that, I hope to make it an annual event at Mines that alternates between introductory and advanced topics,” Toberer said.

Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |
Ashley Spurgeon, Editorial Assistant, Mines magazine | 303-273-3959 |

Faculty in the departments of Chemistry and Chemical and Biological Engineering have been awarded $320,000 by the National Science Foundation to turn bacteria into a more sustainable source of jet fuel.

Fiona Davies and Nanette Boyle inspect a dish of blue-green algae.

Chemistry Assistant Research Professor Fiona Davies, left, and Chemical and Biological Engineering Assistant Professor Nanette Boyle inspect a dish of blue-green algae.

CBE Assistant Professor Nanette Boyle, principal investigator, and Chemistry Assistant Research Professor Fiona Davies, co-PI, are using photosynthetic bacteria commonly known as blue-green algae to produce a compound called limonene.

“Limonene is the compound in citrus essential oils which gives them their distinctive scent,” Davies said. “It’s an ideal precursor for aviation fuel because of its high energy density and structural similarity to jet fuel.” This means limonene can simply be blended with current petroleum-based fuels with no changes needed in the existing transport fuel infrastructure.

While some of the increasing demand for energy in the transportation sector can be replaced with vehicles that run on renewable electricity, the aviation, shipping and long-haul trucking industries will still require liquid fuel.

The bacteria—Synechococcus sp. PC 7002—is very similar to plants in that it grows on carbon dioxide and light alone. It essentially functions as a catalytic factory where enzymes in the cell directly convert carbon dioxide into limonene.

“It doesn’t produce limonene naturally, but we have engineered it to produce limonene by introducing a single enzyme from a limonene-producing plant—spearmint,” Boyle said. “Our current limonene production yields are not high enough to be economically feasible, therefore the funded research is focused on rewiring the metabolism of the cell to direct more carbon toward limonene.”

Boyle and Davies will use computational modeling to predict how they can divert more carbon flux to limonene, then use genetic engineering techniques to modify the bacterium’s metabolism to increase production.

Cyanobacteria—or bacteria that obtain their energy through photosynthesis—have been engineered to produce various industrially useful compounds such as ethanol, butanol and isoprene, which Davies has worked with previously. However, yields are typically low, and little progress has been made because the metabolism of the cell is so tightly controlled. “Our study will actually pinpoint where the tightly controlled parts of metabolism are so that we eliminate them specifically,” Davies said.

“Overall, our work will develop a far more sustainable and environmentally friendly source of fuel for the aviation industry because it is produced directly from carbon in the atmosphere instead of the limited fossil fuel reserves, and it removes carbon from the atmosphere to assist with efforts to reduce global warming,” Boyle said.

The project will also include educational activities, with Boyle and Davies mentoring a team of college and high school students to participate in the International Genetically Engineered Machines competition. The program, also known as iGEM, promotes active learning in the field of molecular biology.


Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |
Ashley Spurgeon, Editorial Assistant, Mines magazine | 303-273-3959 |

A multidisciplinary team, led by the Ben L. Fryrear Professor of Civil and Environmental Engineering Tzahi Cath, has received a $1 million award from the National Science Foundation to develop an innovative monitoring and control system for small wastewater treatment facilities.

The project, titled “Self-Correcting Energy-Efficient Water Reclamation Systems for Tailored Water Reuse at Decentralized Facilities,” draws on the bioreactor at Mines Park, which treats more than 7,000 gallons of domestic wastewater each day, and will integrate existing and new wireless sensor networks to monitor water quality and for process monitoring and control.

“Improved monitoring of water quality and early warning of treatment system vulnerabilities are critical to protecting the public and the environment,” said Cath. “The smart service system we are building uses a network of simple, existing sensors and a novel wireless sensor network. These new, smart sensor technologies can learn from past performance, predict future performance and adapt the system to achieve preset objectives.”

Water pipes with electronic gauges are shown, as the professor kneels to read the information and a student records the data.

Professor Tzahi Cath and a graduate student take readings at the AQWATEC Laboratory.

In addition to being more energy and resource efficient, the new system will benefit many small communities that operate decentralized wastewater treatment facilities and don’t have the resources to improve their system.

Cath also attributed the project’s selection to the foundation laid by the Engineering Research Center for Re-Inventing the Nation’s Urban Water Infrastructure, also known as ReNUWIt, at Colorado School of Mines. “All of this is only possible because ReNUWIt at Mines that has been building these partnerships in an effort to develop new strategies for water management and treatment,” said Cath.

After testing the new monitoring and control system at Mines Park, the team will work with industry partners from Aqua-Aerobic Systems and Kennedy/Jenks Consulting as well as broader context partners such as Ramey Environmental in Frederick, Colorado, to deploy, incorporate and test the system at existing small, decentralized treatment plants.

The team includes Professor Tracy Camp from the Division of Computer Science, Assistant Professor Salman Mohagheghi from the Division of Electrical Engineering, and Associate Professor Hussein Amery from the Division of Liberal Arts and International Studies, as well as professors Amanda Hering and Michael Poor at Baylor University. The team will also include graduate and undergraduate students from CEE and CS.

The grant is one of 13 awarded by the NSF’s Partnerships for Innovation: Building Innovation Capacity program, in support of innovative partnership projects that create new human-centric service systems.

 “The National Science Foundation fosters innovation and partnerships between academic researchers and industry, catalyzing interdisciplinary projects to understand and design smart systems and technologies of the future,” said Grace Wang, acting assistant director, NSF Directorate for Engineering. “These 13 projects are at the forefront of the human-technology frontier, driving innovation to solve problems to benefit society and improve life as we know it.”


Deirdre Keating, Communications Manager, College of Engineering & Computational Sciences | 303-384-2358 |
Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |

A physicist with four degrees from Colorado School of Mines is part of a research team that has found a possible solution to one of the major challenges of facial recognition systems: makeup.

Alex YuffaMines graduate Alex Yuffa, with lead researcher Nathaniel Short, Gorden Videen, and Shuowen Hu, was published in the July 2016 issue of the journal Applied Optics with a paper titled “Effects of surface materials on polarimetric-thermal measurements: applications to face recognition.” The researchers are part of the Image Processing Branch of the U.S. Army Research Laboratory in Maryland.

Face recognition has become a key tool in fields such as security and forensics. Although the accuracy of visible-spectrum facial recognition systems has rapidly increased, and techniques to address changes in light, pose and expression have been developed, cosmetics still pose a challenge as they distort the perceived shapes of faces.

The researchers found that polarimetric-thermal imaging—which measures the thermal infrared emissions of an object, or in this case, faces—are essentially immune to the effects of makeup. The materials commonly used in cosmetics and face paint are good thermal emitters, meaning they have little impact on the heat transferred from the face. This means polarimetric-thermal images provide additional facial details that could otherwise be concealed.

The team determined this by applying various cosmetic and similar materials to a metallic sphere and measuring their thermal conductivity, as well as comparing thermal imaging of faces before and after the application of makeup.

“Our study has demonstrated polarimetric-thermal imaging can be substantially more robust to face paints, and to a degree cosmetics, for facial recognition than visible imaging,” said Short. “Our experiments show how face paints and cosmetics degrade the performance of traditional facial-recognition methods and we provide a new approach to mitigating this effect using polarimetric-thermal imaging.” This technique could also provide advantages in nighttime conditions.

Polarimetric-thermal imaging can reveal facial details in the presence of surface materials such as face paints and cosmetics. Photo courtesy of Eric Proctor, William Parks, U.S. Army Research Laboratory, Maryland, USA

One of the challenges of using this technique is the small size of the existing polarimetric-thermal facial database. “Large sample pools are needed to develop and train complex machine-learning techniques such as neural networks, computer programs that attempt to imitate the human brain to make connections and draw conclusions,” Short said.

“This work was started by my postdoc advisor and me as a fun side project, namely, reconstructing a 3D human face from 2D polarimetric images,” Yuffa said. That work was featured on the cover of Applied Optics in 2014. “After the initial success, we teamed up with image processing collaborators (aka face-recognition people) and used what we learned in that application context.” Yuffa said this most recent research has resulted in one pending patent, and more on the way.

Yuffa earned bachelor’s degrees in engineering physics and math, and holds an MS and PhD in applied physics, all from Mines. “I’m a high school dropout who came to Mines via the Red Rocks Community College route,” said Yuffa. After 12 years at Mines (1999 to 2013, with a two-year break), he joined the Army Research Laboratory in 2013 as a postdoctoral researcher, then as a physical scientist.

“I really liked my time in Mines, and Meyer Hall was my second home,” Yuffa said. The most useful skill he acquired in Golden is the ability to teach himself almost any subject. “On numerous occasions in my career, I had to master new areas with little to no guidance by relying on the independent learner skills that I obtained at Mines,” he said, giving particular credit to Physics faculty members John DeSanto, David Wood, Paul Martin and John Scales.

Yuffa is returning to Colorado this September to join the National Institute of Standards and Technology in Boulder as a physicist.

Read the paper:


Mark Ramirez, Communications Manager, College of Applied Science & Engineering | 303-384-2622 |
Deirdre Keating, Communications Manager, College of Engineering & Computational Sciences | 303-384-2358 |



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