Members

Principal Investigator

Prof. Orlando J. Rojas

Director of the Biobased Colloids and Materials (BiCMat)

Director of the Bioproducts Institute

Orlando Rojas vision

(Click on the image for details)

Our research group

BiCMat is a diverse group of talented individuals, each with their own particular strengths and areas of study. We have created specialized sub-groups for our researchers to create meaningful collaborations and scientific impacts.

Learn about our activities outside the labs

Support team

Dr. Ran Bi

Lab Manager

PhD Microbiology, KTH (2016)

Polysaccharide and lignin fractionation and modification.

LinkedIn

ran.bi@ubc.ca

Dr. Ran Bi is the lab manager and senior researcher in the BiCMat group. She received her Ph.D. degree from the Royal Institute of Technology (KTH) in Sweden, where she worked on the biodegradation of lignocellulose materials. After moving to Canada, she started at UBC as a post-doctoral researcher in Wood Science, Forestry, focusing on enzymatic and chemical pre-treatment of mechanical pulps to repurpose the traditional thermal-mechanical mill for the production of high value-added bio-based nanomaterials. She currently oversees lab management, including equipment and daily operations. Additionally, she collaborates closely with other researchers in the group to facilitate communication between different subgroups. Her own research focuses on bioconversion, biofabrication, and valorization.

Ayako Takagi

Industrial Designer, Emily Carr Art and Design University, Vancouver

Sustainable design, papermaking, 3D modeling/rendering

LinkedIn

ayako.takagi@chbe.ubc.ca

Ayako Takagi is an industrial designer working at the UBC BioProducts Institute, where she collaborates with researchers to prototype and to develop sustainable bio-products. Ayako has a particular interest in ancient traditional techniques related to papermaking and their philosophy of care for their products. She is exploring how to apply traditional artisans’ knowledge to the latest scientific research in order to tackle climate change issues and develop sustainable societies. While Ayako enjoys collaborating with scientists, she is also interested in communication on an interdisciplinary level and exploring how to share design and science research with public audiences, allowing her to involve non-designers in her research.

Polyaromatics, Extractives and Bioactives sub-group

Dr. Jingqian Chen

Group leader

PhD, Chemical Engineering, University of British Columbia (2020)

Reaction kinetics, Lignin particles, Fiber fragmentation

Google Scholar, LinkedIn

jchen@chbe.ubc.ca

Jingqian works as a postdoctoral fellow in BiCMat, leading the “Polyaromatics, Extractives and Bioactives” subgroup. She received a Ph.D. in Chemical and Biological Engineering (University of British Columbia, UBC) in 2020. Her Ph.D. research focuses on hemicellulose depolymerization kinetics, cellulose refining and fragmentation kinetics, kraft pulping, and hemicellulose adsorption. Jingqian obtained M.Sc.E. in Chemical Engineering (University of Michigan) on biodiesel production from microalgae. Afterward, she worked as a R&D scientist in the coal to chemical technology industry. Her most recent work relates to lignin nanoparticle fractionation, aggregation kinetics, cellulose nanofibrils processing, and material applications.

Xuetong Shi

MSc. KTH, Aalto University (2019)/PhD student, University of British Columbia

Functionalized wood, phase change composite materials.

Research Gate

xtshi@mail.ubc.ca

Xuetong Shi is a PhD student in UBC’s Department of Chemical and Biological Engineering. She received her dual master’s degree in Polymer Technology at KTH Royal Institute of Technology (Sweden) and Aalto University (Finland), under the supervision of Dr. Rojas. During this time, she mastered research skills in the areas of cellulose nanofibrils, phase change materials, thermal energy storage and related phenomena. Her current research focuses on the development of multifunctional wood by physical and chemical modification.

Marina Mehling

PhD student, University of British Columbia ​

Synthetic biology, plant biology and bioprocessing.

Google Scholar, ResearchGate, LinkedIn

mmehling@student.ubc.ca

Marina joined the BiCMat group in September 2021 as a PhD student in Chemical & Biological Engineering. She earned a B.S. in Biological Engineering from Purdue University. Her previous research experiences involved work in synthetic and structural biology at the U.S. Department of Agriculture, Purdue Cramer Lab, and the Joint BioEnergy Institute at UC Berkeley. This work inspire Marina to synergize biobased polymers (namely cellulose and natural polyphenols) with engineered proteins. Her work realizes biocompatible and biodegradable materials that can meet advanced applications in diagnostics, tissue engineering, and filtration. Outside of lab, Marina enjoys cooking plant-based meals and going on long walks.

Isabella Howley

Undergraduate Student, Faculty of Chemical & Biological Engineering

bacterial cellulose, bioprocessing

LinkedIn

ihowley@student.ubc.ca

Isabella joined BiCMat in early 2023 under the mentorship of PhD student Marina Mehling. Isabella is an undergraduate student working towards her BASc (expected 2025) in the Department of Chemical and Biological Engineering at UBC. She investigates the interface of materials science and biology, where she is working with bacterial cellulose and tannins from novel, biological sources to create bio-based materials with applications in smart textiles and filtration. Outside the lab, Isabella can be found rowing on the Fraser River with the UBC Thunderbirds varsity rowing team.

Conrad Chiu

Undergraduate Student, Faculty of Science

bacterial cellulose

cchiu10@student.ubc.ca

Conrad is an undergraduate student in the Science One program in the Faculty of Science at UBC. He joined BiCMat in early 2024 under the mentorship of PhD student Marina Mehling. His work is centered on engineering viable corneal tissues for transplants from bacterial cellulose, which offers potential biomedical applications. Through his research, Conrad aims to introduce bacterial cellulose as a competitive alternative to current corneal tissue options. Outside of the lab, Conrad enjoys exploring the great outdoors, venturing to new restaurants, and travelling.

Xun Niu

PhD student, University of British Columbia,

Nanjing Forestry University, Aalto University

Bacteria cellulose, bark extractives, functional supraparticles

Research Gate

niuxun@mail.ubc.ca

Xun Niu did her bachelor and master degrees in Chemical Engineering from Nanjing Forestry University (2019). Her main research focused on cellulose nanofiber modification for functional composites and packaging applications. In the third year of her master, she had the opportunity to work as an exchange student with Dr. Rojas’s group at Aalto University, Finland. Then she started her Ph.D. program at UBC in September 2020. Her current research interest continues to be on bioproduct development, specializing in the valorization of wood bark components. 

Gio Ferson Bautista

PhD candidate (Chemistry), University of British Columbia

Flavonoids, bark extractives

LinkedIn

gmbautista@chem.ubc.ca

Gio obtained his Bachelor’s degree in Agricultural Chemistry from the University of the Philippines in 2017 where he carried out research in the area of natural products chemistry. Afterwards, he worked as a research assistant in the Philippine’s Nuclear Research Institute where he studied radiation protection agents. In 2021, he started his graduate studies in chemistry under the supervision of Prof. Orlando Rojas, where he is trying to understand the compounds found in trees and how they can be utilized.

Daniel Barker-Rothschild

PhD student, University of British Columbia, MSc. Chem. Eng. University of Alberta (2022)

Lignin chemistry, engineering,  valorization

LinkedIn

dbarkerr@student.ubc.ca

Daniel is a PhD student in the Department of Chemical and Biological Engineering. He acquired his BSc. (2020) and MSc. (2022) degrees in Chemical Engineering from the University of Alberta. His research background includes lignin extraction, characterization, drought stress response mechanisms of trees and multivariate data analysis applied to chemical systems. Daniel’s current research focuses on using chemometrics to develop structure-property relationships between lignin feedstocks, their polymeric properties, and their resulting material product attributes.

Julia Azzi

MSc student, University of British Columbia

Lignin nanoparticles, engineering

Research Gate, LinkedIn

julia.azzi@ubc.ca

Julia is an M.Sc. student in Chemical & Biological Engineering at UBC. Prior to joining the BiCMat group, she earned a B.Sc. in Medical and Biological Physics from McMaster University. Through research placements in soft matter physics, particle physics, and sustainable bioplastics, Julia’s interests gravitated to materials science with applications in sustainability. Outside the lab, Julia enjoys Zumba, tap dancing, swimming, and reading.

Matthew Cao

MSc student, University of British Columbia

Bark extractives, functional supraparticles

mattcao@student.ubc.ca

Matthew joined the BiCMat group in September 2023 as an MSc. student. He obtained his BSc. at the University of Toronto in the Materials Science Specialist program. During Summer 2022, he had the opportunity to work as a research exchange student at the institute for Integrated Cell-Material Sciences (iCeMS) in Kyoto University, where he studied the supramolecular assembly of porous materials. His current research focuses on the self-assembly processes of bioextractives. 

Prottasha Sarker

PhD student, NC State University / Co-advised with Prof. Saad Khan

Rheology of bio-based hydrogels

LinkedIn

Bin Zhao

Lignin carbon materials

LinkedIn

Micro/Nanomaterials & Multiphases sub-group

Dr. Yi Lu

Group leader

PhD Chem Eng, University of Alberta (2020).

Colloids and Interfaces, Multiphase systems, Self-assembly, Living matters, Machine learning

Google Scholar, ResearchGate, LinkedIn

yi.lu@ubc.ca

Dr. Yi Lu is a postdoctoral research fellow and the sub-group leader of Micro/Nanomaterials & Multiphase systems. He received his Ph.D. degree at the University of Alberta in 2020. His current research focuses on colloidal and interfacial science, multiphase systems, self-assembly, and living matter. Aside from work, he is passionate about snowboarding, hiking, and wildlife sightseeing.

Yeedo Chun

PhD student, University of British Columbia

Cellulosic foams, microfluidics, multiphase systems

LinkedIn, ResearchGate

yeedo@mail.ubc.ca

Yeedo joined the BiCMat group as a Ph.D. student in Chemical & Biological Engineering in 2020 after receiving his B.ASc. in Materials Engineering. Arriving with knowledge focused in conventional thermosets, he sought to work with cleaner, more sustainable chemistries and pursue applications that would displace harmful materials in high throughput industries. Yeedo hopes to one day offer novel materials to the fashion industry that will result in drastically reduced pollution, safe and just working conditions for all throughout our products’ life cycles, and new possibilities in the manufacture and design of our garments.

Matheus Barros

PhD student, University of British Columbia

Corn starch, Pickering emulsion, mechanochemistry

Research Gate, LinkedIn, ORCID

barrosm@student.ubc.ca

As a VIRS scholarship recipient from Brazil, Matheus joined the BiCMat group in May 2023. He holds a Master’s degree in Chemistry from the Federal University of Ceará (Brazil). His research experience involves the creation, in-depth characterization, and use of biopolymers, specifically bacterial cellulose and starch. His present study is concentrated on the creation and usage of starch based Pickering emulsions. 

Marianelly Esquivel

PhD student, Universidad Nacional Costa Rica

Nanochitin

Google Scholar

mesquive@una.ac.cr

Marianelly Esquivel is a researcher at the Polymer Research Laboratory (POLIUNA) at the Universidad Nacional (UNA), Costa Rica. She is a Ph.D. candidate at the interuniversity doctoral program DOCINADE with UNA and UBC. She is trained in Industrial Chemistry (UNA) and holds a M.Sc. degree in Forest Products (Universidad de Guadalajara, México). Her research interests focus on the use of aquaculture and agro-industrial waste to extract high value-added materials. This serves as the basis for the generation of new materials and products, contributing to the development of a bioeconomy framework in her own Costa Rica.

Dr. Carolina S F Picone (Unicamp, Brazil)

Professor University of Campinas (Unicamp), Brazil

Biopolymers, Food Science and Technology, Colloids and Interfaces, Emulsions

Google Scholar, ORCID, Research ID

c.siqueirafrancopicone@ubc.ca

Dr. Carolina S. F. Picone is a visiting Professor in Prof. Rojas’s BiCMat group. She is Professor at the School of Food Engineering, University of Campinas (Unicamp-Brazil) and head of the Laboratory of Food Colloids (LMA). She earned her PhD and MSc in Food Engineering from Unicamp. Her research is focused on biopolymer interactions as a route to novel encapsulation, emulsification and controlled delivery of functional food ingredients.

Minke Yang

Food Science and Engineering/ South China Agricultural University

Bio-based emulsion, encapsulation and delivery, polyphenol

minkyang@student.ubc.ca

Minke joined the Orlando’s group in Oct. 2023. She obtained her master’s degree in Food Science and Engineering from South China Agricultural University in 2022. Her previous research is about the encapsulation and delivery of tea polyphenol through hydrogel. Now she is willing to explore more colloid systems with different functions. Out of the lab., you can also find her in the UBC dance club and Yoga studio. Sports make her more energetic.

Xin Shu

PhD student, University of British Columbia

Colloidal materials, Multiphase system

ResearchGate

xinshu98@student.ubc.ca

Xin joined the BiCMat group in January 2024 as a PhD student in Chemical & Biological Engineering. She received her bachelor’s and master’s degrees in Food Science & Engineering from China Agricultural University. Xin previously worked on natural-based colloidal systems (nanocomplexes, emulsions, and composite hydrogels) for the encapsulation and delivery of food bioactive compounds. With the knowledge gained from her research, Xin will continue working on the structure-property relationship and interaction of biopolymers to improve their application outcomes. In her leisure time, Xin enjoys crocheting, playing the blues harmonica, and working out.

Yi Hu

PhD student, Northeast forestry university

Cellulose material, nanofibrous aerogel

Google Scholar, ResearchGate

huyi96@student.ubc.ca

Yi joined the BiCMat group in January 2024 as a joint PhD student at the University of British Columbia. He graduated from Northeast Forestry University with a bachelor’s degree in Wood Science and engineering. His previous research has focused on cellulose, electrospun nanofibers, 3D aerogels and exploring functionalization and applications. Now, Yi is interested in CO2 capture from the seawater by biomass materials.

Peipei Wang

PhD student, Nanjing Forestry University

Enzyme hydrolysis

peiepi03@student.ubc.ca

Roozbeh Abidnejad

Foams

Google Scholar

Ya Zhu

Biobased multiphase systems and applications

Researchgate

Fibers and Fibrillated (ligno)cellulose sub-group

Dr. Tianyu Guo

Group leader

PhD Nanjing Forestry University (2020)

Bioinspired nanomaterials, Wearable electronics, Interfacial chemistry

Google Scholar, LinkedIn

tianyu.guo@ubc.ca

Dr. Tianyu Guo received her Ph.D. in Pulp and Paper Engineering from the Nanjing Forestry University and was a joint student at the University of British Columbia (UBC). Earlier experiences included her research in University of News Brunswick. Her current work is focused on biomacromolecule-based functionalization and applications. As a postdoctoral fellow, she is working on bio-based inks and foam-forming for wearable electronics and bio-based filtration systems. She is also a senior researcher at UBC Bioproducts Institute, working on interfacial chemistry of biomass materials.

Dr. Yizhou Sang

PhD Chemical Eng., University of British Columbia (2012)

Polymer chemistry, wet-end paper chemistry, bioproduct development.

LinkedIn

yizhou.sang@ubc.ca

Dr. Yizhou Sang earned his Ph.D. in Chemical and Biological Engineering from University of British Columbia. He is also a registered professional engineer (P. Eng.) with Engineers and Geoscientists BC (EGBC). His career has focused on technology development and commercialization in the context of climate change and energy management with two successful bio-based product commercialization. Currently, he is a research associate at UBC Bioproducts Institute leading efforts related to bioproduct development.

Mahyar Panahi Sarmad

PhD student, University of British Columbia

Smart Materials, Aerogels, Nanomaterials, Additive Manufacturing

Google Scholar, LinkedIn

mahyar13@student.ubc.ca

Mahyar is a trainee in material science and engineering who aspires to lead the cutting-edge field of multi-responsive and intelligent materials. He actively engaged in understanding foundational concepts of polymer science while still an undergraduate student. He earned a MSc degree (Jan 2018), focused on the use of conductive nanoparticles in dielectric elastomer actuators (artificial muscles) and aerogel design and applications. As an Elite scholar for ca. 2 years, he also investigated shape memory materials. He spent two-and-a-half years working as a research associate at Jiangnan University. Currently, his research at UBC revolves around the functionality of Aquabots, additive manufacturing (3D&4D printing and liquid-liquid printing), smart polymer composites (sensors and actuators) and EMI shielding.

Samuel Hahn

Master student, University of British Columbia / Co-advised with Prof. Johan Foster

Nanocelluloses

sam.hahn@ubc.ca

Samuel is working with Industry partners in Edmonton to valorize hemp hurd fines. He works with microbial and chemical elements to develop pilot-ready processes for the production of nanocellulosic materials for a variety of applications. These vary from polymer compositing to non-dietary fibre. Samuel is particularly interested in integrating live biological elements in continuous processes, and developing on the concept of a zero waste biorefinery.

Samantha Pritchard

MSc student, University of British Columbia

Cellulose nanofibrils, surface chemistry

spritchard@chem.ubc.ca

Samantha joined the group in 2021 after completing her H.B.Sc. in Materials Chemistry at McGill University. She studies water-based microtemplating and bio-sourced catechols as surface modifications, creating cellulose materials with tailorable surface chemistry. Some of this work is in collaboration with industrial design research through Emily Carr University, considering how researchers shape their perspective on the materials they study. Samantha is interested in how functional biomaterials can be used promote a circular economy. In her free time she can be found hiking to find the best lakes for swimming or biking towards baked goods.

Juan Pablo Calvo

Master student, University of British Columbia

Wet-spinning, CCU, Coral Reef Engineering, Bio Packaging

LinkedIn

jpcalvoc@student.ubc.ca

Juan Pablo joined the BiCMat group in early 2023 and is currently pursuing a MASc in Chemical & Biological Engineering at UBC. He holds two bachelor’s degrees in Chemical and Environmental Engineering from Universidad de los Andes, Colombia. His work is oriented to the production of cellulose and chitin filaments through wet-spinning. Additionally, he is interested in Carbon Capture and Utilization (CCU) and Coral Reef Engineering.

Michaela Samanta

Bachelor of Science, Research Assistant 

Protein Engineering, Synthetic Biology, Biopolymer

LinkedIn

michae99@student.ubc.ca

Michaela joined the group as a UBC undergraduate student. Her past affiliations include the UBC Biofoundry, the Indonesian Institute of Sciences (LIPI), Sanofi Pasteur, LSI Microbiology, and Eyam Vaccines. At the University of British Columbia, Michaela led the wet lab team in the International Genetically Engineered Machine Competition. She is also a current member of the World Bank’s Advisory Group. Michaela is currently dedicated to developing sustainable solutions in the industry, focusing on net-zero waste and carbon emissions technologies and challenging greenwashing practices. Outside of the lab, she enjoys reading, creating visual arts, and having a picnic.

Tina Raeisi Gahrooee

PhD student, University of British Columbia

Nanochitin, Chitosan

Linked In

tinarg@student.ubc.ca

Tina is currently pursuing her PhD in the Department of Chemical and Biological Engineering at UBC. During her master’s at the same department at UBC, her research centred around investigating the mechanical behaviour of Cellulose Nanocrystals for sustainable applications. Prior to her academic journey at UBC, Tina successfully earned a master’s degree at the Queen Mary University of London. During her time there, she specialized in Biomedical Engineering with Biomaterials and Tissue Engineering where she characterized novel peptides for biomedical purposes. Tina hopes her chemical and biomedical engineering background would help her design a novel application from biomass resources for water and air decontamination. Aside from her work, Tina enjoys running, windsurfing, and hiking.

Isabel Carvajal

VIRS student, National University, Costa Rica

Nanocellulose, 3D Bioprinting, biopolymers

LinkedIn

isacarva@student.ubc.ca

Isabel is an Industrial Chemistry undergraduate student at the National University of Costa Rica (UNA) and is visiting UBC as a part of her undergraduate thesis at UNA. Her research is focused on utilizing biopolymer materials obtained from agricultural waste products to form hydrogels with 3D bioprinting capacity. She is a research assistant at the Polymer Research Laboratory at UNA, but is also in collaboration with the Physics Department and School of Veterinary Medicine at UNA to develop a bioink material made from biomass that can be used for biomedical and bioprinting applications in Costa Rica. Through this project Isabel is a VIRS at BPI for four months, where she will be able to further contribute to efforts in developing a bioeconomy framework and a biomedical research hub in Costa Rica. 

Javier Alonso Corrales Vargas

VIRS student, Chemical Engineering, University of Costa Rica

Nanocellulose, Nanohydroxyapatite, 3D Printing

LinkedIn

javiercv@student.ubc.ca

Javier joined the BiCMat group in January 2024 as a VIRS student from the Chemical Engineering department at the University of Costa Rica. His research focuses on developing a nanocellulose hydrogel rich in nanohydroxyapatite for use in 3D printing for tissue engineering applications. His background lies in the utilization of agroindustrial waste for high-value applications and in the extraction of nanocellulose and cellulose derivatives, contributing to the advancement of the bioeconomy in Costa Rica.

Alvaro Gonzalez Vogel (Celulosa Arauco)

Electrodialysis

LinkedIn

Interfaces, Adsorption and Computational Analysis sub-group

Dr. Sameer Mhatre

Group leader

PhD Chem Eng, Indian Institute of Technology, Bombay (2014)

Soft matter physics, Electro-hydrodynamics, multiphases, thin films.

LinkedIn

sameer.mhatre@ubc.ca

Zhangmin Wan

PhD student, University of British Columbia / Co-advised with Prof. Simcha Srebnik

Atomic simulations, Crystallography, Thermodynamics, Nanomechanical research.

ResearchGate

hugowan@student.ubc.ca

Zhangmin Wan is a Ph.D. student at the University of British Columbia and a member of the Interfaces, Adsorption, and Computational Analisys sub-group. He received his MSc. degree at Nanjing Forestry University in 2020. His current research field is related to the elastoplastic behavior of chitin nanocrystals using both experimental tools (X-ray and atomic force microscopy techniques) and simulation methods (molecular dynamics simulations, quantum chemistry, and the first principle calculations).

Ahmadreza Ghaffarkhah

PhD student, UBC-O

Carbon-based nanomaterials; MOFs; polymer processing; 3D printing; liquid-in-liquid printing

Google Scholar, LinkedIn

ah.ghaffarkhah@ubc.ca

Ahmadreza Ghaffarkhah is currently pursuing his Ph.D. in the School of Engineering at the University of British Columbia, Okanagan Campus. Additionally, he is a visiting Ph.D. student at the Bioproducts Institute, University of British Columbia, Vancouver Campus. His research focuses on several areas, including the synthesis of carbon-based nanomaterials and MOFs, polymer processing and forming, and intrinsically conductive polymers. He is actively involved in exploring 3D printing and liquid-in-liquid printing techniques for carbon-based hydrogels and inks.

Praven Kamalanathan

Research Assistant, University of British Columbia

Foam Forming Technology, Bio-based Product Development

LinkedIn

praven1@student.ubc.ca

Praven obtained his Bachelor of Applied Science in Materials Engineering from the University of British Columbia, Vancouver in 2020 and joined BiCMat afterwards to use his knowledge in developing bio-based materials. His Research has been focused on Bioproduct Development using foam forming technology and exploration of Reticular Chemistry. He hopes to hybridize and combine the two fields for utilization in multifaceted applications inclusive of Water Remediation, Gas storage and separation, and Energy Harvesting for a brighter and more sustainable future.

Dr. Farhad Ahmadijokani

PhD Mechanical Eng., University of British Columbia (2024)

MOF, water remediation

Farhad.ahmadijokani@ubc.ca

Dr. Farhad Ahmadijokani earned his Ph.D. in Mechanical Engineering from UBC, with a concentration on the application of Metal-Organic Frameworks (MOFs) in environmental contexts. His ongoing research is centered around exploring the interface between MOFs and biobased polymers for ultimate environmental applications. In his role as a postdoctoral fellow, he is actively engaged in structuring MOFs and biobased polymers through techniques such as wet spinning, electrospinning, and 3D printing, with a specific focus on their utilization in carbon dioxide (CO2) capture.

Yuma Hashimoto

Undergrad students, University of British Columbia

Ronan Sheppard

Undergrad students, University of British Columbia

Amir Reza Mohebi

PhD student, University of British Columbia / Co-advised with Prof. James Feng

LinkedIn, GoogleScholar

Hydrogel Mechanics; CFD; Fluid and Solid Mechanics

mohebi@student.ubc.ca

Amir joined the BiCMat group as a Ph.D. candidate in Chemical Engineering in September 2023. He completed his Bachelor’s and Master’s degrees at Amirkabir University of Technology, specializing in Fog harvesting and Zero Liquid Discharge during his undergraduate studies. Transitioning to his master’s, he focused on CFD-DEM simulation of moving bed Catalytic reactors. Currently pursuing his Ph.D., Amir’s research centers on hydrogel mechanics within the wet spinning process. Passionate about materials science and engineering, Amir enjoys solving real-world problems through the application of mathematics and simulation. Outside of research, he can be found working out, experimenting with new recipes in the kitchen, and Camping out close to bears.

Haider Iftikhar

Tribocharging