PUMERA group

Nanobiosystems: Materials, Nano and Analytical Chemistry

Welcome to PUMERA group

Our research is highly interdisciplinary, on the interface between electrochemistry, materials, analytical, physical and biological chemistry and nanotechnology. We carry out fundamental studies as well as applied research. For details, see our Research webpage.

 

News:

 

November 2016

 

November 2016
Our group research was featured in "Pushing Frontiers" Magazine (09/2016 issue). Click here for details.

 

 

Our 4t year PhD student James presented at Falling Walls Conference in Berlin and at Green Talent Forum (also in Germany). Featured in BBC magazine (click bellow)

 

 

 

October 2016

 

Our paper (together with Prof. Sofer's group, Prague) on graphane nanostripes was featured on cover of Angew. Chem. Int. Ed. (see bellow)

 

 

 

 

 

Our Nature Comm (with two Czech groups) was featured in the Czech Republic press, see here (in Czech, click on the links):

Czech TV

Czech Radio

Lidové noviny

Týden

Novinky

Prima

Aktualne

 

 

Our review on the control of micro and nanomotors was featured as frontispiece in Chem Eur J. (IF 5.8)

 

 

 

Our paper (with Czech group from Olomouc and Prague) on Air-stable superparamagnetic metal nanoparticles traped in graphene oxide matrix got  published in Nature Communications. You can read it here.

 

Nanomotors fly to Berlin! James won first place in NTU competition "Falling Walls Lab" with bubble propelled nanomotors. He is no. 1 in whole NTU and he will go and represent NTU in Berlin (fully taken care of, of course). Congrats!

 

 

 

July 2016

 

We got some more papers, three new Angew. Chem. Int. Ed., 1x Adv. Mater, 1x Adv. Funct. Mater (covers) plus a lot of ACS Catal. and others. Couple of our covers for summer, see bellow. Nature Communications is on its way.

 

 

 

 

 

 

 

 

 

 

 

 

other papers published in June-July by our group:

Shu Min: ACS Catal (IF 9): Aromatic exfoliation of the TMDs

Adriano: ACS Catal (IF 9): Templated electrodeposition of molybdenum sulfide

Carmen: Adv Funct Mater (IF 11.38): WS2 NPs as biolabel: COVER

 Xinyi: Adv Funct Mater (IF 11.38): Electrocatalysis of PtS2, PtSe2 and PtTe2

James: ACS Sensor: EC detection of micromotors

CK: PCCP (IF 4.44): S doped ball milled graphene contains impurities from milling

Adeline: Analyst (IF 4.1): MoS2 as label for biosensing

Rozi: ChemPhysChem (IF 3.13): Impact electrochem of graphene labeled with metal NPs

 

 

ASPIRE forum at Hong Kong hosted the best young energy-related researchers from Asia. Xinyi was one of 5 representative from whole NTU (only one for SPMS) in this forum "Developing Sustainable Urban Environment and Low Carbon Economy". Some pictures from the event.

 

 


June 2016

 

Dr. Wang's group reunion in Hannover at MNM 2016.

 

 

 

Dr. Wang's group reunion in Bath at ESEAC 2016.

 

 

 

Summer and exchange research students joined us:


Koo Sung Phang

(Summer research)
 

LEONG SHI XUAN

(SMURF (MIT)
Summer research)

SEAH XIN YUN (Summer research)

DONG QI

(Summer research)

JEEVIT HRA GUNASE GARAN

(Summer research)

MONICA MEGA WATI

(Summer research)


LEE HUI LIN

(Summer research)


HINDIA NAHDI

(MSc Sorbone exchange student)

 
     

 

 

May 2016

 

All of our Chinese PhD students, Ms. Hong Wang and Lu Wang received Award of Excellence from Chinese Embassy (this awared is given to ~500 Chinese PhD students world wide, so we are pround to have 1/250 the best (and we have only the best) Chinese scholars inb the World. See picture here.

 

 

Our update review on graphene electrochemistry was featured on the cover of Chem Soc Rev. (IF 33), see bellow.

 

 

 

 

April 2016 

Xinyi, our PhD student, received the Best Poster award at International Society of Electrochemistry meeting at New Zealand, where she presented.

 

 Congratulations!

 

Some pictures from Xinyi after the New Zealand conference.

 

 

 

 

Nasuha, our FYP student, received RSC award for the best FYP poster. Congratulations!

 

Martin received award as being the Editorial Board Member who published the greatest number of articles in all RSC journals in 2013-2015.

 

 

 

March 2016 

James and Stanislav's paper on Manipulating micromotors with molecular switch published in ACS Nano (IF 11+) March 2016: Photochromic Spatiotemporal Control of Bubble-Propelled Micromotors by a Spiropyran Molecular Switch.

 

 



Paper by Wei Zhe on Fe(0) Nanomotors in Ton Quantities (10^20 Units) for Environmental Remediation (in collaboration with Radek Zboril) was highlighted on the cover of Chem. Eur J. (IF 5.8).

 

 

 

 

February 2016 

Paper on anisotropy of black phosphorus crystal (in collaboration with Zdenek Sofer) was highlighted on the cover of Angew. Chem. Int. Ed. (IF 11.26). See here.

 

 

 

Our paper on 3D printing structures for electrochemistry (opening new field) was highlighted on the cover of Adv. Funct. Mater (IF 11.8). See here.

 

 

 

Paper on C3N4 catalyti activity (or lack of thereof) was highlighted on the cover of ChemPhysChem (IF 3.5).

 

 


January 2016 

We welcome new Master and Final Year Project student.

Vitor Marin
(MSc student)
 
Yew Ying Teng
(MSc student)

PANG SHI NING (FYP)

NASUHA BTE ROHAIZAD
(FYP student)

CHUA XING JUAN
(FYP Student)
 

 

 

Our paper on black phosphorus nanoparticles and their impact electrochemistry highlighted on the cover of Chem Commun (IF 6.8).

 

 

 

Our paper on magnetism in MoS2 was highlighted on the back cover of Nanoscale (IF 7.3).

 

 

 

 

our 1st ACS Nano in 2016; this time on the anti-MoS2 TMD - T2S with inverse structure. It has very interesting electronic and electrochemical properties. Read below. First author, Xinyi, our second year PhD student:

 

Adriano's Chem. Eur. J. (IF 5.7)  on electrochemical exfoliation of graphene was recognized as "HOT paper" by Wiley and highlighted on the cover.

 

 

 

December 2015 

Chem Commun. (IF 6.8) paper on the investigation of mechanism of graphene oxide reduction by hydrazine (result of 4 year research project of CK) was gas published published and highlighted as cover.

 

 

November 2015 

 

Angew. Chem. Int. Ed. (IF 11.26) paper on gas sensing at black phopshorus by Carmen as the first author was published and highlighted as cover. See details here (PDF). Hot paper by Wiley.

 

 

 

 

Our review in Chem. Rev. (IF 46+) on electrochemistry of transition metal dichalcogenides was just published online. See here for more.


The review was highlighted on the cover of the journal.

 

 

Alex's paper on the influence of proton and electron sources on hydrogenation efficiency of Birch reaction on graphene was published as frontispiece in Chem Eur J.

 

 

 

Stefan W. Hell (Nobel Prize 2014, chemistry, for ultrahigh resolution microscopy) visited SPMS and spent 2 h discussing with our students. Portrayed with Adeline (our 4th year PhD student):

 

 

 

Adriano's paper "Electrochemically Exfoliated Graphene and Graphene Oxide for Energy Storage and Electrochemistry Applications," was highlighted in ChemistryViews.

 

See here:

chem Views 

 

 

 

September 2015 

 

Advanced Functional Materials (IF 11.8) paper on gas sensing at 1T-WS2 by Carmen as the first author was published. See details here.

 

 

Our paper on toxicity of black phosphorus in Chem Eur J is featured as hot paper and on cover.

 

Our group in September 2015. 

 

thumbnail image: The Cytotoxicity of Layered Black Phosphorus

Our paper on toxicity of black phosphorus in Chem Eur J is featured in Chemistry Views.
chem Views

 

 

August 2015 

 

Our review in Chem. Rev. (IF 40+) on nano/micromotors was just published with page numbers. See here for more.


 

 

CK's paper on double halogenated graphene was just published in Small.

 

Richard Webster's paper (with our small contribution on CNTs) was published on cover of ChemPlusChem celebrating 50 years of Singapore.

 

We welcome new PhD student and two new master students.

Yong Wang
(PhD student)

Rozi Alice Thearle
(UK, MSc student)

Jack Fawdon
(UK, MSc student)

 

 

June-July 2015 

our 5th ACS Nano this year, this time on the impact electrochemistry of TMDs: they can be either oxidized inherently or they can electrocatalyze hydrogen evolution reaction. First author, Chee Shan, our master student:

 

 

Chee Shan finished her MSc with grand finale of ACSNano paper (see above) and moved to NIE to study to become high school professor of chemistry.  We wish her quiet classrooms.

CK was invited to prestigious Lindau Nobel Laureate Meeting in Germany. Not yet as Laureate, but as JW says, the best is yet to come!

 

Our group member, research fellow Stanislav, moved in July to Assistant Professor position at Yale-NUS (Singapore). We wish him all the best!

 

May 2015 

 

Our group profile published in Chem Eur J.  Find out what we do and why we do it here (PDF).

 


CK's paper on the -NH2 functionalization of graphene using Bucherer reaction was featured on the cover of Chem. Eur. J

 

 

Colins's paper on the profound influence of geographic origin of graphite on graphene properties was highlighted on the cover of Chem. Eur. J

 

 

Our papers published in May 2015:

 

Xinyi: ACSNano (IF 12): EC activation of TMDs

Zdenek: ACSNano (IF 12): Labeling graphene by deuterium

CK: Chem Eur J (IF 5.6): Bucherer on GO: COVER + PROFILE

Colin: Chem Eur J (IF 5.6): Different mines give different graphite and consequently graphene: COVER

Hwee Ling: Chem Eur J (IF 5.6): Graphol and hydrogenated graphene (her last paper with us)

Chee Shan: J. Mat. Chem. A. (IF 6.7): Layered MO(OH) for electrocatalysis

Adeline: ChemElectroChem: GO labels for food.

  

 

April 2015 

 

Chemistry @ NTU (that is, us) is according Nature Ixdex no. 5 in the World (we are better Harvard, ETH, Tokyo and others; of course much better than any of the individual institutes of Max Planck or CAS). We are happy that we contributed our small share to this last year by 1 PNAS, 1 JACS, 2 Angew. Chem. and few of Chem. Comm. papers.

 

 

 

Cover in Advanced Materials
(IF 15) (with Radek, CZ), coauthors Adriano and Adeline.

 

 

 

our 4th ACS Nano this year, this time on the deuterium labelling of GO to investigate its structure (with Zdenek, CZ) :

Abstract Image

 

 

...and...our 3nd ACS Nano this year, this time on activation of TMD catalysis (by Xinyi, 1st year PhD student) :

Figure

 

Our 2nd ACS Nano this year, this time on monothiolated graphenes (by CK):

Figure 

 

 

Colin's paper "Geographical and Geological Origin of Natural Graphite Heavily Influence the Electrical and Electrochemical Properties of Chemically Modified Graphenes" was highlighted in ChemistryViews.

 

See here:

chem Views 

 

 

 

Our papers published in April 2015:

 

CK: ACSNano (IF 12) - introduction SH group to graphene.

CK: ChemPhysChem (IF 3.5) - Misfit layered structures for electrochemistry

Shu Min: Chem Eur J (IF 5.6) - Edge and basal plane of MoS2

CheeShan: J. Mater Chem. A (IF 6.7) - Superconducotrs for electrochemistry

Marcella: Electrochem Comm (IF 4.5) - Impact of Mo NPs

Carmen: Electrochem Comm (IF 4.5) - TMDs capacitance

Adriano, Adeline contributed to Adv. Mater (IF 15) to SH-FG

Zafir: Electroanalysis (IF 2.5) - Detection of mycotoxins

  

 

March 2015  

Martin is named as one of top ten most prolific authors of Chem Asian J in the past 10 years. See here for more.

 

Our papers published in March 2015:

CK: ACS Nano (IF 12) G-QDs by C60 opening using Hummers method

CK: Small (IF 8.5) Metastability of graphene oxide (FRONTISPIECE)

Lu: ChemElectroChem: Electrochemistry of black phosphorus (COVER, including group profile)

Adriano and Xinyi: Electrochem Commun (IF 4.5): MoS2 ball milling

 

Figure

 ACS Nano on C60 (by CK, 1st this year).

 

Lu's paper on N-doped graphenes was among the 30 most accessed articles in Journal of Materials Chemistry C in 2014 . See here for more.

 

Group profile was published in ChemElectroChem. See here what we do and why!

 

 

CK's paper on long term (un)stability of graphene oxide was featured as frontispiece in Small

 

 

Lu's paper on black phosphorus was featured on the cover of ChemElectroChem as VIP paper.

 

 

 

February 2015 

 

Our papers published in Jan-Feb 2015:

 

 Adriano: Small (IF 8.5): MoS2 - different intercalants (COVER)

Adriano: ChemPhysChem (IF 3.5): Eu labeling of GO ox groups

CK: ChemEurJ (IF 5.6): Layered PbI2 - golden rain

Zafir: Nanoscale (IF 6.7): MoS2 limited window

Hwee Ling: ChemElectroChem: review on doping of G

CheeShan: Electrochem Comm (IF 4.3): Graphene QDs for electrochemistry

 

 

Pumera's group published 73 peer reviewed papers last year (2014) with average IF of 7.05. See here for details. This includes 1 Chem Rev, 1 Chem Soc Rev, 1 JACS, 1 PNAS, 4 ACSNano, 1 Adv. Funct. Mater,  1 Small, 1 Chem Mater, 12 Chem Eur J, 10 Nanoscale and a lot of others. Thanks to all group members for their dedication to finding how Nature really works.

 

We got a lots of covers last year.

 

 


Martin was appointed as Associate Editor of PCCP (Physical Chemistry Chemical Physics, published by RSC, IF=4.2).

 

 

Adriano's paper was published as frontispiece in Small.

 

 

 

January 2015 

 

James' review paper was published as frontispiece in Chem Eur J.

 

 

 

We welcome new post-doctoral fellow, Dr. Bahareh Kherzi

 

we also welcome 4 new honor (FYP) students.

 

  
John (co-supervised with Dr. Bonanni)
 
Yew Ying Teng

 

Hui Kai Hwee (co-supervised with Dr. Bonanni)


Daniel Ng Yee Fan

 

 


 

December 2014 

 

Adeline was selected for P&G iNNOVATION CAMP 2104. Congratullations!

 

 

 

 

Our papers published in December 2014:

 


Abstract Image
Alex, ACS Nano (IF 13): Electrochemistry of MoSe2, WS2, WSe2

James, Chem Eur J (IF 5.8): Review on Micromotors and Environment

Xinyi, Chem Eur J (IF 5.8): Tuning of MoS2 by electrochemistry

James, JPCC (IF 4.8): EC monitoring of capsules

Adeline, Electrochem. Comm. (IF 4.5): Impedance on MoS2, WS2

Elaine, RSC Adv, graphene+MoS2 toxicity (review)

 

 

 

 

We welcome new post-doctoral researcher:


Dr. Carmen Mayorga
Research Fellow

 

 

November 2014 

 

Covers and Frontispieces in November

 

James' paper on macromotors based on acetylene propulsion was featured at cover of Chem Comm.

 

 

CK's paper showing that al reagents used for fabricaton of reduced graphene unintentionally dope graphene was featured on cover of Chem Eur J.

 

 

Hong's paper on Ir catalysed graphene motor was featured as frontispiece in Chem Eur J

 

 

Paper from Zdenek's group (with our very small contribution) was feature on cover in New J. Chem. (RSC) (showing that GO emits quite large polyaromatic molecules when heated)

 

  

 

Special issue on Graphene in Analytics edited by Pumera, Polsky, Banks was published in Anal. Bioanal. Chem. See here.

 

  

 

Our papers published in November 2014:

 

Hong: Chem Eur J (IF5.6) Iridium catalyst loaded graphene motor. (fronstispiece)

Elaine: Nanoscale (IF 6.7) MoS2 toxicity is dependant on exfoliation (the more exfoliated, the more toxic).

CK: Chem Eur J (IF 5.6) Chemically prepared graophene is unintentionaly doped by elements which are parts of the reagents (cover).

James: Chem. Comm. (IF 6.7) Acetylene powered bubble motor.

Wei Zhe: ChemPhysChem (IF  3.6) Detection of Fe in CNTs by electrochemistry.

 

 

We welcome new post-doctoral researcher:


Dr. Stanislav Presolski
Research Fellow

 

October 2014 

Our papers published in October 2014:

 

 

Chee Shan: JPCC (IF4.5) Permanganate electrochemically reduced GO shows limited potential window in bothcathodic and anodic regions.

 

 

 

September 2014 

 

We have new (2nd) paper in PNAS as a lead group. This time (surprise) .... showing that even ultrapure graphite get contaminated with almost whole periodic table during processing to graphene. See here.

PNAS

 

 

 

Our papers published in September 2014:

 

 

Zafir: Electroanal. (IF2.8) Myxotoxins

Guanjia: Nanoscale (IF 6.7) - Self propelled Pt coconut motor

Hong: Nanoscale (IF 6.7) - Self propelled banana Pt motor

Colin: PNAS (10) - ultrapure graphene soaks impurities from reagents

Lu: Chem. Comm. (6.7) - CNT contain impurities which are responsible of ORR

Adeline: Nanoscale (6.7) - MoS2 as label for DNA detection

James: ChemPhysChem (IF 3.4) - GO as absorbent for heavy metals

 

Cover 

 

We say Hello/Goodbye. We welcome 2 new PhD students, Xinyi and Naziah and we say goodbye to 3 PhD students who submitted their thesis: Guanjia, Hwee Ling and Elaine.

 

 


Chia Xinyi

Naziah Binte Mohamad Latiff

 

We also welcome 4 new undergrads, Chng Chu'er, Hui Kai Hwee, Tan Choy Gek (all 3 FYP students) and Xie Yumin (URECA).

 

 

Summer 2014 

 

Summer is over - CK had his convocation (so he is officially doctor of philosophy - PhD) and we published some good papers. See:

 

 

 

 

 

 


 

Perspective on "Impact Electrochemistry" in ACS Nano - Click here.

 


 

Research article on "layered misfit chalcogenides" in Chemistry of Materials (by undergrad student Chee Shan) - Click here.

 


 

 

Doping graphene with uranium and thorium for oxygen reduction (with Zdenek Sofer) in ACS Nano: click here.

 

 


 

Frontispiece in Adv. Funct. Mater. on oxygen free graphene (with Zdenek):

 

 

June 2014 

 

Our review on Electrochemistry of Graphene and Related Materials, result of 2 years of work (40 pages) was  just published in Chem Rev (IF 40+). Click here.

 

 

Xinyi's recent paper in Chem Eur J (IF 5.8) on Electrochemistry of Fluorographites was highlighted on Chemistry Views. Click here.

 

F-graphite 

 

 

chem Views

 

 

 

May 2014 

Our papers published in May 2014:

 

Alessandra: ACS Nano (IF 13+): Oxidation debris is responsible for inherent electrochem. activity of graphene oxide. 

Elaine: Chem Eur J (IF 5.8): Toxicity of graphAne
Xinyi: Chem Eur J (IF 5.8): Electrochemistry of F-graphite

Martin: J. Mater. Chem. A. (IF 5.9)  – Electrochemistry of MoS2 and TMDs (review).

Chee Shan: PCCP (IF 3.9): Electrochemical tuning of graphene oxide for biomolecule detection

 

 

Elaine's recent paper in Chem Eur J (IF 5.8) on toxicity of graphAne was highlighted on Chemistry Views. Click here.

 

thumbnail image: Graphene, the Future of Nanomaterials or a Health Hazard? 

 

chem Views

 

 

Congratulations to Alessandra on her new ACS Nano (#3) paper. Click here.

 

 

 

April 2014 

 

Our papers published in April 2014:

 

 

Hwee Ling: Small (IF 7.8): Metal depleted graphene from thin air (highlighted in JOVE)

Adriano: ChemSusChem (IF 7.5): N,B-doping of G does not increases its capacitance.

Hwee Ling: Chem Eur J (IF 5.8): P-doped graphenes

James: Chem Eur J (IF 5.8, COVER): Towards artificial inorganic microfish (Pb2+ poisons jets)

Hong: JPCC (IF 4.8) – influence of surfactants on the microjets motion

Lu: JMCC (IF 6.3) - N-doping of graphene

Alex: Electrochem Commun (IF 4.5): Direct Electrochemisry of Colloidal GO

 

 

See our review on Layered transition metal dichalcogenides for electrochemical energy generation and storage. Link.

 

TOC

 

 

 

 

 

James' paper on "Self-Propelled Microfish Robot for Selective Detection of Pb2+" in Chem Eur J (IF 5.8) was featured on the COVER.

 

 

 



Our April papers include high profile cases, such as Hwee Ling's paper in Small (IF 7.8) and Adriano's in ChemSusChem (IF 7.48).

 

 

 


March 2014 

 

Congratulations to James. His paper on "Self-Propelled Microfish Robot for Selective Detection of Pb2+" in Chem Eur J (IF 5.8) was featured on Chemistry Views website. See link.

 

chem Views

 


 

 

thumbnail image: Self-Propelled Microfish Robot for Selective Detection of Pb<sup>2+</sup>

 

Our papers published in March 2014:

 

Lu: J. Mater. Chem. C (IF 6.1) – N doped graphenes

Shu Min: PCCP (IF 3.8) – EC purification of graphenes

Goda: ChemElectroChem– metallic NP electrochem

Hong: JPCC (IF 4.8) – influence of surfactants on the microjets motion

 

 

 

February 2014 

 

Congratulations to Hong on her new JACS on self-propelled micromotors!

 

JACS

 

 

CK's paper on the selective reduction of epoxy group on graphene oxide was published in Chem Eur J and highlighted on the cover.

 

 

This article was highlighted in Chemistry Views, see "The sp2 graphene selection"

  chem Views


 

 

 

 

Elaine's paper on the toxicity of microjets was published in Nanoscale and highlighted on the cover.

 

 

 

 

Our papers published in February 2014:

 

Hong: JACS (IF10.7): MnO2/Ag - bubblejets

Chee Shan: Analyst (IF 3.9) - sensing on graphene ribbons

CK: ChEJ (IF 5.8; cover): CK – removal epoxy group from graphene oxide

 

 

 

January 2014

 

Special issue in Electroanalysis on Graphene Electrochemistry, guest edited by Martin Pumera, Ronen Polsky and Alessandra Bonanni was published. See here.

  

Thumbnail image of graphical abstract
 

 

 

Alessandra's article was highlighted in Chemistry Views, see "Anchors for Biosensors"

  chem Views


 

 

Martin was appointed as Member of Editorial Boards of:

 

Chem Eur J (Wiley, IF 5.6)

Electrochem. Commun. (Elsevier, IF 4.5)

ChemElectroChem (Wiley)

 

starting from Jan 2014.

 

 

Guanjia's paper on the low cost fabrication of microjets was published in J. Mater. Chem A and highlighted on the cover.

 

 

 

 

Alessandra's paper on the modification of graphene with DNA strands was published in Chem. Eur. J. and highlighted on the cover.

 

 

 

 

 

December 2013

Lu's paper on the influence of metallic impurities in graphene on oxygen reduction reaction was published in Angew. Chem. Int. Ed. (as VIP paper) and highlighted cover of Angew. Chem.

 

 

 

 

 

..."old news" from 2010-2013 here. 

Covers and Highlights
(since 2009)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 



 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

chej13-elaine

 

La

 

 

 

 

 

 

 

 

 

Alessandra Chem Eur J 

 

Analyst 2012

 

 

 

 

 

 

 

Chem Asian Azo 2011

 

Chem Eur J 2011

 

Chem Asian J Autumn

 

AFM

 

Nanoscale

 

 

 

HotChilli 

CAJ 2011 Nanotoxicity

 

Chem Eur J 2010

Nanorobots


Collaborations

Map

  • Prof. Yuji Miyahara & Prof. T. Goda, Tokyo, Japan
  • Prof. Jay Han, MIT, USA via Singapore-MIT Alliance for R&T (SMART)SMART
  • Prof. Adrian Fisher, Cambridge University via Cambridge Centre for Carbon Reduction in Chemical Technology C4T
  • Prof. Samuel Sanchez, Max Planck Institute for Autonomous Systems, Germany
  • Prof. Alberto Escarpa(Microfluidics and Biochips), University of Alcalá, Spain
  • Prof. Vladimír Matolín (XPS), Charles University, Czech Republic

 

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