Workshop on Specialty Optical Fibers and their Applications

Playing Cellular Golf in Microstructured Fibres

Sebastián Estcheverry, Aziza Sudirman, Fredrik Laurell, and Walter Margulis

WF1A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Low-temperature Manufacture of Optical Fibres

Gilberto Brambilla and Lieke Van Putten

WF1A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Anderson Localization Fibres

Arash Mafi

WF1A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Rare earth doped fiber lasers based on zeolite method

Yasushi Fujimoto

WF1A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Soft Glass Highly Nonlinear Optical Fibers and Their Applications

Yasutake Ohishi, Lei Zhang, Tonglei Cheng, Tong Hoang Tuan, Lui Lai, and Takenobu Suzuki

WF1A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Hollow core fibers for optically pumped mid-IR fiber lasers

Jonathan C Knight, Muhammad Rosdi Abu Hassan, Fei Yu, and William J Wadsworth

WF2A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Hollow Annular Core Fibres

Kyunghwan Oh

WF2A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Combining Fluid Dynamics and Electromagnetics Modelling to Improve Hollow Core Photonic Band Gap Fibres

G. T. Jasion, E. R. Numkam Fokoua, J. S. Shrimpton, D. J. Richardson, and F. Poletti

WF2A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

High-power picosecond pulse delivery through hollow core photonic band gap fibers

Mattia Michieletto, Mette M. Johansen, Jens K. Lyngsø, Jesper Lægsgaard, Ole Bang, and Thomas T. Alkeskjold

WF2A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Very Large Mode Area Pixelated Bragg Fibers

Y. Quiquempois, J-P Yehouessi, O. Vanvincq, G. Bouwmans, A. Cassez, and L. Bigot

WF2A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Multicore Fibers

Axel Schulzgen, Amy Van Newkirk, James Anderson, Guillermo Salceda-Delgado, Zeinab S. Eznaveh, Jose E. Antonio-Lopez, Cen Xia, Guifang Li, Roy G. van Uden, Frans M. Huijskens, Hugo de Waardt, Ton A. Koonen, Chigo Okonkwo, and Rodrigo Amezcua Correa

WF3A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Multicore EDFA

Yukihiro Tsuchida

WF3A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Ultrafast laser inscription of 3D components for spatially multiplexed telecommunications

Robert R. Thomson

WF3A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Lab-on-fiber Devices

Jacques Albert

WF4A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Optical Fibers in Medicine: Biophotonics at Work

David D. Sampson

WF4A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Coatings for Harsh Environment Applications of Optical Fibers

Andrei A. Stolov, Jacob A. Wrubel, Jie Li, and Michael J. Hines

WF4A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Femtosecond Laser Inscription of Bragg and Complex Gratings in Low-Loss Polymer and Silica Optical Fibers

Kyriacos Kalli, Amedee Lacraz, and Michael Polis

WF4A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Fabrication of regenerated grating using carbon dioxide laser

K. S. Lim, M. H. Lai, D. S. Gunawardena, and H. Ahmad

WF4A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Hollow-core Fiber Gas Lasers

William J. Wadsworth, Adrian L. Love, and Jonathan C. Knight

WT1A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Novel Fibers for High Performance Lasers And Amplifiers

Michalis Zervas

WT1A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Thulium and holmium doped fibre lasers for 2 µm applications

Alexander Hemming, Nikita Simakov, John Haub, and Adrian Carter

WT1A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Bismuth-doped Optical Fibers: Advances and New Developments

E. M. Dianov, S. V. Firstov, and M. A. Melkumov

WT1A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Diode Pumped Bi-doped Fiber Laser Operating at 1360nm

N. K. Thipparapu, A. A. Umnikov, S. Jain, P. Barua, and J. K. Sahu

WT1A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Tm3+ or Ho3+ Doped Fluorotellurite Microstructure Fiber for 2μm Lasing

Chuanfei Yao, Zhixu Jia, Shunbin Wang, Chunfeng He, Guanshi Qin, and Weiping Qin

WT1A.6 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Ultra large mode area fibers with aperiodic cladding structure for high power single mode lasers

Philippe Roy, Romain Dauliat, Aurélien Benoît, Dia Darwich, Jens Kobelke, Kay Schuster, Stephan Grimm, François Salin, and Raphaël Jamier

WT2A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Advances in Integration of Photonic Crystal Fibers in High-power Fiber Laser

Pascal Dupriez and Claude Aguergarary

WT2A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

High pulse energy stable wave-break soliton in a long ring-cavity fiber laser

Jiaqi Zhou and Xijia Gu

WT2A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

High-power Efficient Yb-doped Fiber Laser with Low Quantum Defect

Guancheng Gu, Zhengyong Liu, Fanting Kong, Hwayaw Tam, Ramesh K. Shori, and Liang Dong

WT2A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

High Power Performance of Rod Fiber Amplifiers

Mette M. Johansen, Mattia Michieletto, Torben Kristensen, Thomas T. Alkeskjold, and Jesper Lægsgaard

WT2A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Novel microstructured fibres for supercontinuum generation

X. Jiang, N.Y. Joly, F. Babic, R. Sopalla, R. Song, J. Lousteau, D. Milanese, J.C. Travers, and P. St.J. Russell

WT3A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Nonlinear effects in novel photonic crystal fibers

Nicolas Joly

WT3A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Core-to-core Crosstalk Management as an Instrument for Constructing Multicore Fiber Based Devices

Ł. Szostkiewicz, A. Ziolowicz, M. Napierala, Ł. Ostrowski, D. Budnicki, M. Jozwik, M. Makara, K. Poturaj, P. Mergo, and T. Nasilowski

WT4A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Optical Properties of Tm3+-doped Microstructured Fiber Fabricated by Plasma Non-chemical Vapor Deposition Method

Changming Xia, Guiyao Zhou, Jiantao Liu, Wei Zhang, Ying Han, and Jinhui Yuan

WT4A.10 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Yb-doped Pedestal Aluminosilicate Fiber through Vapor Phase Doping for High Power Laser Applications

Maitreyee Saha, Sourav Das Chowdhury, Debasis Pal, Atasi Pal, Mrinmay Pal, and Ranjan Sen

WT4A.13 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Er3+ doped low-hydroxyl fluorotellurite microstructured fibers for 2.7 µm laser applications

Zhixu Jia, Chunfeng He, Chuanfei Yao, Shunbin Wang, Guanshi Qin, and Weiping Qin

WT4A.14 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Optical Frequency Comb Generation from a Bismuth-Based Actively Mode-Locked Fiber Ring Laser

Yutaka Fukuchi and Hiroki Shirane

WT4A.15 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Optically tunable monolayer graphene saturable absorber for the control of pulsed fiber laser operation

Jinhwa Gene, Hwan Seong Jeong, Nam Hun Park, Sun Young Choi, Fabian Rotermund, Dong-Il Yeom, and Byoung Yoon Kim

WT4A.16 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Radiation-hardened co-doped optical fiber for high-power 1.5µm amplifier

E. Pinsard, A. Laurent, T. Robin, and B. Cadier

WT4A.17 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Stability study of ultra-long Random distributed feedback fiber laser based on Erbium fiber

I. Aporta, M. A. Quintela, H. S. G. Roufael, and J. M. López-Higuera

WT4A.18 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Stable at High Temperatures LPG’s Inscribed by a Femtosecond Fiber Laser

H. S. G. Roufael, A. Quintela, M. Lomer, and J. M. Lopez-Higuera

WT4A.19 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Higher order modes management in hole-assisted fibers

Anna Ziolowicz, Michal Szymanski, Lukasz Ostrowski, Marek Napierala, Marta Filipowicz, Krzysztof Poturaj, Mariusz Makara, Pawel Mergo, and Tomasz Nasilowski

WT4A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Specklegram interference fiber sensing

Mauro Lomer, Luis Rodriguez-Cobo, I. Aporta, and Jose Miguel Lopez-Higuera

WT4A.20 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

A Tunable All-Fiber Laser Based on a Stress-Optic Phase Modulator and a Chirped Fiber Bragg Grating

Zhangwei Yu, M. Malmström, O. Tarasenko, W. Margulis, and F. Laurell

WT4A.21 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Pockels fibers by optical poling

I.C. S. Carvalho, Oleksandr Tarasenko, Alexandre R. Camara, João M. B. Pereira, and Walter Margulis

WT4A.22 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

A microspherical resonator embedded inside a microstructured optical fiber taper

M.G. Konstantinou, K. Kosma, W. Margulis, and S. Pissadakis

WT4A.23 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Octave-spanning spectrum of mode-locked Er-doped fiber laser at 208MHz repetition rate in a dispersion-varying tellurite microstructured fiber

Fang Wang, Zhixu Jia, Chuanfei Yao, Shunbin Wang, Guanshi Qin, Changfeng Wu, and Weiping Qin

WT4A.24 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Ho3+/Yb3+ co-doped Tellurite glasses and fibers for 1.2 µm laser applications

Shunbin Wang, Zhixu Jia, Chuanfeng Yao, Chunfeng He, Guanshi Qin, and Weiping Qin

WT4A.25 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Carbon nanotube modified optical fiber surface with novel coating method for non-linear and SPR application

Yang Zhang, Fang Wang, Lu Song, Michael Jakubinek, Yiying Gu, Benoit Simard, and Jacques Albert

WT4A.26 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Type IIa Bragg gratings formed in active fibers

Yang Ran, Fu-Rong Feng, and Bai-Ou Guan

WT4A.27 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

A Novel Optical Microfiber Device Based on Mesoporous SiO2 Nanospheres Arrays

Mingfei Ding, Yunyun Huang, and Bai-Ou Guan

WT4A.28 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Five-core Fiber for Astronomy Spectrometer Application

Gongdai Chen, Jing Yang, Chunying Guan, Libo Yuan, Hua Bai, and Xiangqun Cui

WT4A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

In-situ protein detection based on cut-off mode monitoring of a tilted fiber Bragg grating biosensor

Jian Xu, Xuejun Zhang, Linzi Han, Liu Fu, Tuan Guo, and Bai-Ou Guan

WT4A.30 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

High sensitive thrombin protein detection using a plasmonic tilted fiber grating biosensor

Linzi Han, Ze Wu, Xuejun Zhang, Qiangqiang Fu, Jian Xu, Yong Tang, Tuan Guo, and Bai-Ou Guan

WT4A.31 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

In-situ glucose detection in human serum using a plasmonic tilted fiber grating with etched silver coating

Xuejun Zhang, Ze Wu, Jian Xu, Linzi Han, Qiangqiang Fu, Yong Tang, Tuan Guo, and Bai-Ou Guan

WT4A.32 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Design of Fundamental Mode Filter based on Long-Period Grating Fiber

Ming-Yang Chen and Jin Wei

WT4A.33 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Stable Operation of All-Optical Fibre Photoacoustic Sensors

Yuechuan Lin, Wei Jin, Jun Ma, Chao Wang, Fan Yang, and Hoi Lut Ho

WT4A.34 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Collimated Fibers with Bragg Gratings for Strain Sensing of Rapidly Rotating Mechanical Structures

Garry Berkovic, Shlomi Zilberman, Ehud Shafir, Yair Saadi, Ohad Mazor, and Tal Goichman

WT4A.35 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Long-Period Fiber Grating Inscribed in a Suspended-core Fiber by Femtosecond Laser Pulses

Yufeng Zhang, Yongqin Yu, Shuangchen Ruan, Chenlin Du, and Wen Zhou

WT4A.36 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

High Temperature Sensing head based on 45° Tilted Fiber End Fabricated by Femtosecond Laser in Thin Core Fiber

Wen Zhou, Yongqin Yu, Shuangchen Ruan, and Yufeng Zhang

WT4A.37 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Bent Optical Fiber Bragg Grating Embedded in PDMS for Vertical Compression Load Sensor

Luo Niu, Chi Chiu Chan, Kong Pui Wah, and Li Han Chen

WT4A.38 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Fiber Optic pH Sensor Based on Electrostatically Self-Assembled Polymer Multilayer

R. Raghunandhan, L.H. Chen, C.C. Chan, Z.Q. Tou, and P. Zu

WT4A.39 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Asymmetric Very Large Mode Area Fiber with Enhanced Higher Order Mode Delocalization

Zeinab Sanjabi Eznaveh, Enrique Antonio-Lopez, Gisela Lopez-Galmiche, James Anderson, Axel Schülzgen, and Rodrigo Amezcua-Correa

WT4A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

PDMS Film Coated Fiber Volatile Organic Compounds Sensor

Xiangping Ning, Li Han Chen, Chun Liu Zhao, and Chi Chiu Chan

WT4A.40 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Surface Plasmon Biosensor Based on a D-shaped Microstructured Optical Fiber with Rectangular Lattice

Lu Peng, Fukun Shi, Guiyao Zhou, Shu Ge, Zhiyun Hou, and Changming Xia

WT4A.41 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Non-contact Micro Vibration Measurement System Based on Non-equilibrium Optical Fiber Michelson Interferometer

Jie Zhang, Zhenguo Jing, Chuanqi Xing, and Wei Peng

WT4A.42 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

A DNA Sensitive Biosensor in Weak Acid Condition based on Graphene Functional Taper Interferometer

Bo Yu, Yunyun Huang, Mingfei Ding, Lipeng Sun, Yang Ran, and Bai-Ou Guan

WT4A.43 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

3D Bending Sensor Combining Multicore Fiber with a Mode-Selective Photonic Lantern

Amy Van Newkirk, Amado M. Velázquez-Benítez, J. E. Antonio-Lopez, Jacques Albert, Rodrigo Amezcua-Correa, and Axel Schülzgen

WT4A.6 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Background Attenuation of Al-doped Fibers Produced with Vapor Phase Doping Technique

Stanislav Čampelj, Luka Perpar, Peter Lukan, Janko Štajner, Aljaž Ramšak, Andraž Lenardič, and Borut Lenardič

WT4A.8 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Focused Ion Beam Structuring of Exposed-Core Microstructured Optical Fibers

Stephen C. Warren-Smith, Ricardo M. André, Jan Dellith, Manfred Rothhardt, and Hartmut Bartelt

WT4A.9 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Special or Specialty Optical Fibres?

David N. Payne

WW1A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Pushing the limits in the fabrication and properties of soft glass and silica optical fibers

Heike Ebendorff-Heidepriem

WW1A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

New Materials and Functions - Novel Fibre Materials and Fabrication Methods

J. Ballato, T. Hawkins, and P. Dragic

WW2A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Semiconductor optical fibers

A. C. Peacock, F. H. Suhailin, L. Shen, N. Vukovic, S. Mailis, and N. Healy

WW2A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Metamaterial Fibres

Simon C. Fleming, Alexander Argyros, Juliano G. Hayashi, Shicheng Xue, Geoff Barton, and Boris Kuhlmey

WW2A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Miniature Slow Light Delay Lines and Buffers: A Review

Misha Sumetsky

WW2A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Tm3+-doped large core silica fiber fabricated by the nanoporous glass

Yu Yang, Yingbo Chu, Yunxiu Ma, Yinbin Xing, Lei Liao, Jinggang Peng, Jinyan Li, and lvyun Yang

WW2A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

New functions and materials - multimaterial fibers in biology and nanotechnology

Lei Wei

WW3A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Liquid and Metallic Nanowires in Fibers: A Novel Base for Nanophotonics and Optofluidics

Markus A. Schmidt

WW3A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Fabrication of planar waveguides in oxyfluoride glass-ceramics by simple heat-treatment

Kummara Venkata Krishnaiah, Yannick Ledemi, Younes Messaddeq, and Raman Kashyap

WW3A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Novel Wearable RF Textile-Integrated Antennas Made from Multi-Material Fibers

Stepan Gorgutsa, Mazen Khalil, Victor Bélanger-Garnier, Jeff Viens, Benoit Gosselin, Sophie LaRochelle, and Younes Messaddeq

WW3A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Ytterbium-doped oxyfluoride nano-glass-ceramic fibers for laser cooling

Kummara Venkata Krishnaiah, Yannick Ledemi, Elton Soares de Lima Filho, Galina Nemova, Younes Messaddeq, and Raman Kashyap

WW3A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Yb3+ doped large core silica fiber based on glass phase-separation technology

Yingbo Chu, Yu Yang, Yunxiu Ma, Nengli Dai, Jinyan Li, and Luyun Yang

WW3A.6 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Smart Fibers for Sensing

Tanya Monro and Shahraam Afshar

WW4A.1 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Chalcogenide Glass Fiber Tape

Yannick Ledemi, Jerome Lapointe, Steeve Morency, Ye-Jin Yu, Younes Messaddeq, and Raman Kashyap

WW4A.2 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Indium Fluoride Glass Fibers for Mid-Infrared applications

Mohammed Saad, Robert Pafchek, Paul Foy, Zack Jiang, David Gardner, and Patrick Hawkins

WW4A.3 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

Hollow Core Antiresonant Fibers in Borosilicate Glass

Walter Belardi, Nicholas White, Joris Lousteau, Xian Feng, and Francesco Poletti

WW4A.4 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF

New Trends in POF for Data Communications

Yasuhiro Koike

WW4A.5 Workshop on Specialty Optical Fibers and their Applications (WSOF) 2015 View: PDF