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In the news

LEISHMAFIBER Workshop
The 3rd LEISHMAFIBER workshop was celebrated on the 10th of November at the Universidad Carlos III, in the frame of the coordinated project "Multifunctional sprayable wound dressings obtained by solution blow spinning for the treatment of skin diseases" (PID2020-112713RB-C21, -C22). In this occasion, the workshop was organised as an international meeting, NEW CHALLENGES FROM THE PERSPECTIVE OF NANOFIBROUS MATERIALS, with invited internationally renowned scientists who imparted key-note lectures, and aimed to promote the participation of young researchers. Our PhD students Zeinab Dirany, Javier Carriles, Nerea Guembe and  Paolo Ginatta presented their results in the form of flash presentations and posters.

Collaboration Grant (Ministerio de Educación)
Carmen Tabuenca and Cristina Galindo (Double Degree in Chemistry and Biochemistry, 4th year), who are doing her Final Degree Projects in SUMBET group, under the supervision of Itziar Vélaz, Javier Peñas and Adrián Durán, have been awarded a Collaboration Grant by the Ministerio de Educación for the academic year 2023-2024. 

FPU grant
Nerea Guembe has been granted an FPU fellowship (Ayudas para la formación de Profesorado Universitario 2022) for PhD studies. She recently presented her MSc Thesis with the title "Study of the Leishmanicidal Activity of Pentamidine-Functionalized Microfibers Produced by Solution Blow Spinning (SBS)". Her research will focus on the production of functionalised polymeric fibers for the treatment of parasitic diseases, under the supervision of Prof. Gustavo González Gaitano (SUMBET) and Prof. Paul Nguewa (ISTUN), in the frame of the LEISHMAFIBER project.

Special Issue (guest editor)
Prof. Adrián Durán will be the guest editor of the Special Issue "Mineralogical Appoaches to Archaeological and Cultural Heritage Materials" within the journal "Minerals" (Impact Factor: 2.5) 

Conference award
Zeinab Dirany has been awarded the "Best Short Presentation" at the 7th European Cyclodextrin Conference, held in Budapest, September 5-8 2023, with the communication "Formulations of miltefosine using cyclodextrins and polymeric surfactants: Structural characterization and application against leishmaniasis". SUMBET was also represented in the Conference by Prof. González-Gaitano, who delivered an invited lecture on "Cyclodextrins, surfactants and self-assembly". The next conference in these series of European meetings will take place in Milano, in 2025.

Sabbatical
María Elisa Martínez Barbosa, professor of Chemical Engineering at the University of Sonora (Mexico), has joined the Department for a sabbatical. She has obtained a grant from the Programa de Movilidad para Investigadores de la Universidad de Navarra and will collaborate with Prof. Itziar Vélaz, in the field of drug delivery systems based on chitosan.

Promotion
Prof. Adrián Durán, who obtained the accreditation as Full Professor from the AQU (Agència per a la Qualitat del Sistema Universitari de Catalunya) last March and from the ANECA last november, has been promoted to Catedrático de Universidad. We send Adrián our warmest congratulations for his promotion.

Recent publication
The results of an investigation by Juan Pablo Fuenzalida, Rubén Costa and collaborators from the Technical University of Munich at Straubing and Gustavo González Gaitano SUMBET, has been published in Advanced Materials. In this work, "Genetically Encoded Oligomerization for Protein-Based Lightning Devices", a strategy to design highly stable, bow-tie shaped, fluorescent proteins for their integration into light emitting devices in optoelectronics, has been proposed. This strategy permits a remarkable function-stability of the construct, with light emission preserved for months and high thermal folding stability in different solvents and synthetic polymers. Water-free green-, red-, and white-emitting Bio-HLEDs have been produced, with first-class performance compared to prior-art devices. This publication has been featured as Editor’s Choice article in the journal Advanced Materials. This section showcases innovative and impactful articles with an interdisciplinary character, reporting fundamental and applied research across all aspects of materials science and engineering and its intersection with chemistry, physics, biology, the health and environmental sciences. The paper has been also selected as the front cover of the issue.

Incorporation
Nerea Guembe-Michel (QUI-BQ 2022) has been granted an ADA (Asociación de Amigos de la UN) fellowship for PhD studies. Her research will focus on the production of functionalised polymeric fibers for the treatment of leishmaniasis, under the supervision of Prof. Gustavo González Gaitano (SUMBET) and Prof. Paul Nguewa (ISTUN).

Research stay
Iván Ruiz is currently doing a research stay at the Laboratoire d'Archéologie Moléculaire et Structurale (CNRS/Sorbonne Université) in Paris. Among the tasks he is carrying out is the displacement to different museums in the north of France (Provins, Reims, Châlons-en-Champagne, Soissons...) to analyze some 13th century tiles using non-invasive portable techniques, and the application of archaeomagnetic techniques for the dating of the artworks and their spatial distribution. 

BSc thesis award
Our PhD student, Nerea Guembe, has been awarded the Premio al mejor Trabajo Final de Grado (TFG), organised by the ISTUN (Instituto de Salud Tropical UN), for her degree thesis entitled Pentamidine, Released from Blow Spun Polymeric Microfibers, Impairs Leishmaniasis by Downregulating cycA and cyc6. With these grants, the institute aims to help young researchers who pursue a doctoral degree at the University of Navarra. We congratulate Nerea for her achievement.

2nd LEISHMAFIBER Workshop
The 2nd LEISHMAFIBER workshop was celebrated on the 23rd of May at the Universidad de Navarra, in the frame of the coordinated national project "Multifunctional sprayable wound dressings obtained by solution blow spinning for the treatment of skin diseases" (PID2020-112713RB-C21, -C22). Attendants from the research groups involved in the project, SUMBET, ISTUN and the Universidad Carlos III de Madrid, presented their results in the form of seminars and flash presentations. The intern and RTP students of the degree in Chemistry ascribed to the SUMBET group were also present in the meeting. The next workshop will take place in autumn, in Madrid.

In the news
An investigation from researchers of SUMBET, ISTUN and the Rutherford Appleton Laboratory (UK) has been featured at the ISIS Neutron and Muon Source site. In this research, a new drug delivery system to treat leishmaniasis, based on polymeric mixed micelles and gels, has been investigated using small angle neutron scattering experiments on the Larmor diffractometer. The full paper can be found here.

Doctorate award
Dr. Max Petitjean, who recently finished his Ph.D. dissertation ("Development of Sustainable Polysaccharide Matrices with Hydrophobic Modifications") in our department, has been awarded the Premio Extraordinario de Doctorado (Natural and Applied Sciences program) corresponding to the academic year 2021-2022. We congratulate Max on his achievement and wish him all the best in his professional career. 

In the news
Iván Ruiz Ardanaz, PhD student within the SUMBET group, taught the conference entitled "The secrets of the tiles of Teobaldo: a scientific perspective" last Wednesday, November 9 (2022), at the Museum of Navarra. At the conference, he revealed some of his discoveries related to Navarrese medieval tiles.

PhD dissertation
Leire Goñi Ciáurriz has recently completed the doctoral studies developed in the SUMBET group. On october 27, 2022, she presented her thesis "Development of nanocomposites containing titanium dioxide nanoparticles and cyclodextrins for food packaging applications" and she has received the Cum Laude mention. She has obtained the International Doctorate mention with a long stay (four months) at the Université Paris Est Créteil (UPEC) with Prof Bousserrhine. We congratulate Dr. Goñi for her excellent achievement.

In the news
Prof. Itziar Vélaz has published the article "¿Qué hacemos con los plásticos?" last October 5, 2022, in The Conversation.

Incorporation
Javier Carriles Matanza (QUI-BQ 2021) has been granted an ADA (Asociación de Amigos de la UN) fellowship. His research will focus on the production of polymeric fibers for wound dressings against leishmaniasis under the supervision of Prof. Gustavo González Gaitano (SUMBET) and Prof. Paul Nguewa (ISTUN).

Experiments at the Rutherford-Appleton Laboratory
Small angle neutron scattering experiments have been recently performed at the Rutherford Appleton Laboratory (Oxfordshire, UK), aimed at testing the structure at mesoscopic level of micelles and gels of polymeric surfactants for the treatment of leishmaniasis. Zeinab and Rima Dirany and Gustavo González conducted the experiments, with the assistance of Dr. Gregory Smith, beam scientist of the LARMOR diffractometer. The experiments, funded by the Science and Technology Facilities Council (UK), are framed within the MINECO project “Multifunctional sprayable wound dressings obtained by solution blow spinning for the treatment of skin diseases (PID2020-112713RB-C21)”, from the Ministerio de Ciencia e Innovación.

Award at the 20th International Cyclodextrin Symposium
Zeinab Dirany has been awarded a Young Investigator Training Program grant (Cyclonet YITP2019) to do a research stay at the Universitá di Messina, under the supervision of Prof. Antonino Mazzaglia. The award was presented at the 20th International Cyclodextrin Symposium, held in Naxos (Sicily) from 13-16 of May. SUMBET was represented in the Conference by Zeinab, who presented a poster communication on the use of cyclodextrins for the treatment of leishmaniasis, and Gustavo González-Gaitano. The next edition of the symposium will be held in France (Boulogne sur Mer) in May 2024.

HiloTesis award
Leire Goñi (QUIM+BQM'21), doctoral student in the Department of Chemistry, winner of the "Your Doctoral Thesis in a Twitter Thread: #HiloTesis" award from the University of Navarra, within the context organized by CRUE Spanish Universities. (https://twitter.com/Lei_goni/status/1520519625955590144)

In the news
Sebastian Correa (QUIM’20, MMCC’21) describes his experience in the University. He recently completed his Master Theses “Development and optimization of photocatalysts using chemical coating techniques and assessment of the yields in the removal of organic contaminants in aqueous phase” under the supervisión of Profs. Javier Peñas and Adrian Duran (SUMBET).  

PhD dissertation
Max Petitjean has recently completed the doctoral studies carried out in the SUMBET group with his dissertation viva. The thesis "Development of Sustainable Polysaccharide Matrices with Hydrophobic Modifications" applied the principles of green chemistry to the preparation of biobased materials with various potential applications as sorbents or delivery devices. His PhD work  included the International Doctorate mention with a short stay (5 weeks) at Queen's College Belfast School of Pharmacy and a long stay (four months) at Université de Lille. He has received the Cum Laude mention by the examining panel. We congratulate Dr. Petitjean for his excellent achievement.

SANS experiments at ISIS
The Science and Technology Facilities Council (UK) has funded a project to carry out small angle neutron scattering experiments (SANS) at the Rutherford Appleton Laboratory (Oxfordshire, UK). The experiments, which will be performed in May, will test the structure at mesoscopic level of micelles and gels of polymeric surfactants for the treatment of leishmaniasis, in collaboration with researchers of the Institute of Tropical Health (ISTUN).

Visiting researcher
Antonio Solano (Chemical engineer 2021, Universidad Nacional Autónoma de México) has been granted a research fellowship (Programa de Iniciación a la Investigación CNBBBJ-UNAM-2021) to work on the production of polymeric fibers for biomedical applications. He will work under the supervision of Prof. Itziar Vélaz (SUMBET), until February 2022.

Recent publication
Nature Biotechnology features an article developed at the Institute of Biological and Medical Imaging (Helmholtz Zentrum München) by Juan Pablo Fuenzalida and collaborators on photo-switchable proteins for applications in fluorescence microscopy and optoacoustic imaging methods. We congratulate Juan Pablo and the team at HMZ for the paper (see here a less-technical explanation on switchable proteins by the author for general public)

In the news
Prof. Juana Fernández, on the new electronic system recently implemented in the Comarca de Pamplona to open the rubbish bins, in Diario de Navarra (9/November/2021)

Collaboration Grant (Ministerio de Educación)
Olaia Mendiburu (Degree in Chemistry, 4th year), who is doing her Research Training Program (RTP) in SUMBET, has been awarded a Collaboration Grant by the Ministerio de Educación for the academic year 2021-2022. Her work will focus on the synthesis and characterization of photocatalysts with metallic support for the elimination of emerging pollutants in aqueous phase.

Doctorate award
Dr. Joan Puig Rigall has been awarded the Premio Extraordinario de Doctorado (Natural and Applied Sciences program, 2020-2021), for the thesis "Supramolecular structures of D-alpha-tocopheryl polyethylene glycol succinate, poloxamines, and cyclodextrins: design, characterization, and potential applications as drug delivery systems". We send Joan our warmest congratulations and wish all the best in his new post as Biomaterials Project Leader at Naturemimetix.

New projects
The Ministerio de Ciencia e Innovación (programa Retos de la Sociedad) has funded the coordinated project "Multifunctional sprayable wound dressings obtained by solution blow spinning for the treatment of skin diseases". The project, which involves researchers from SUMBET (coordinator) and research groups ISTUN and UC3M, will be developed until 2024.

Incorporation
Iván Ruiz Ardanaz (QUI2019) has been granted an ADA (Asociación de Amigos de la UN) fellowship. His research will focus on the cultural heritage of Navarre (medieval ceramics) under the supervision of Prof. Adrián Durán (SUMBET) and Prof. Esther Lasheras (LICA)

In the news
Get-together on climatic change with Prof. Juana Fernández in Navarra Television (16/XII/2020)

"With camouflage against parasites". The Heinz Maier-Leibnitz Zentrum features a joint investigation of SUMBET, UC3M, ISTUN and the Jülich Centre for Neutron Science (JCNS)

Summer course
The summer course entitled "Plastic in food. New materials”, held from 19th to 28th of July 2021, was taught by Prof. Itziar Vélaz and Leire Goñi (PhD student). It was organized in collaboration with the Government of Navarra and the Science Museum of the University of Navarra. The most frequently used polymers in food packaging, the new lines of research in applied nanotechnology, and the most common recycling processes were explained.

 

 

Promotion
Prof. Itziar Vélaz Rivas has been promoted to Catedrática in the area of Physical Chemistry. She obtained the accreditation as Full Professor from the AQU (Agència per a la Qualitat del Sistema Universitari de Catalunya) last April. We send Itziar our warmest congratulations for her promotion. 

PhD dissertation
Joan Puig Rigall has recently defended his doctoral dissertation titled "Supramolecular structures of D-alpha-tocopheryl polyethylene glycol succinate, poloxamines, and cyclodextrins: design, characterization, and potential applications as drug delivery systems". The thesis included the International Doctorate mention with a four-month stay at  Purdue University in 2018 and has received the Cum Laude mention by the examining panel. From SUMBET and the Department, we send our warmest congratulations to the newly-inaugurated doctor.

Mobility of PhD students
Leire Goñi has been awarded with a doctoral UN Mobility Grant, aimed to obtain the mention of international doctoral degree. The stay took place in the group of Prof. Bousserrhine, at the Université Paris-Est Créteil (UPEC) from November 2020 to February 2021. The research was focused on studying the antibacterial activity of Cyclodextrin-grafted TiO2 nanoparticles and different biodegradable polymer TiO2 nanocomposites with application in packaging.

AQU accreditation
Prof. Cristina Martínez-Ohárriz has obtained the accreditation as Full Professor from the AQU (Agència per a la Qualitat del Sistema Universitari de Catalunya). We send Cristina our warmest congratulations for her promotion.

SANS experiments at JCNS
EU has recently funded a project to carry out small angle neutron scattering experiments (SANS) at the Jülich Centre for Neutron Science (Münich). The experiments, which will be performed in May, will test the structure at mesoscopic level of new gel formulations based on polymeric surfactants for the treatment of leishmaniasis, in collaboration with researchers of the Institute of Tropical Health and the Universidad Carlos III.

In the news
Prof. Juana Fernández has won the third prize in the 2nd edition of the Contest of Scientific Monologues, organised by the Museo de Ciencias Naturales of the Universidad de Navarra.

AQU accreditation
Prof. Javier Peñas has obtained the accreditation as Full Professor in the area of Chemical Engineering from the AQU (Agència per a la Qualitat del Sistema Universitari de Catalunya). We send Javier our warmest congratulations for the promotion.

Mobility of PhD students
Leire Goñi has been awarded with a doctoral GN Mobility Grant for international research stays. The stay took place in the group of Prof. D. Raúl Quijada, under the supervision of Prof. Humberto Palza at Chile University (Santiago de Chile), during the months of December 2019 and January 2020. The research has been focused on developing thermoplastic polymers for smart food packaging.

6th European Conference on Cyclodextrins
The 6th European Conference on Cyclodextrins was held in Santiago de Compostela last October, after the meetings in Aalborg (2009), Asti (2011), Antalya (2013), Lille (2015) and Lisbon (2017).

The congress covered topics ranging from cyclodextrin production, chemistry and modeling, to applications in diverse fields including analytical chemistry, drug formulation, gene therapy, regenerative medicine, cosmetics, food, bioremediation and agriculture, among others. SUMBET was represented in the Conference by Profs. González-Gaitano, who delivered a plenary lecture on "Supramolecular Chemistry of surfactants and cyclodextrins", Itziar Vélaz, José Ramón Isasi. Our PhD students Leire Goñi and Max Petitjean delivered two flash poster presentations.

Promotion
Prof. Juana Fernández has been promoted to Profesor Titular in the area of Chemical Engineering. She obtained the accreditation from the ANECA (Agencia Nacional de Evaluación de la Calidad y Acreditación) last May. We send Juana our warmest congratulations for her promotion.

In the news
Prof. Juana Fernández has recently published an opinion article in the DN titled "El día del Medio Ambiente o cómo educar en valores"  on the ocassion of the World Environment Day.

New projects
The "Dirección General de Industria, Energía e Innovación" del Gobierno de Navarra has fundad the project "Optimization of the development and management of packaging containing sustainable nanoparticulate materials, for food use", whose main researcher is Prof. Itziar Vélaz. The project is included in the program "Ayudas a Centros tecnológicos y Organismos de investigación y difusión de conocimientos para la realización de proyectos de I+D 2019".

Poster award
Leire Goñi has received the award for the best poster communication at the IV International Summer School on Cyclodextrins, which took place at the Politecnico di Milano from June 10 to 12. This course, held every three years, is aimed at doctoral students and researchers from all over the world working in the field of supramolecular chemistry with cyclodextrins. Idoia Cunnigham, student of the 4th year of Chemistry, has co-authored the communication, entitled "Food packaging films containing TiO2 nanoparticles modified with β-Cyclodextrins: Degradation studies". Read here the news (Spanish)

4th International Summer School on Cyclodextrins
The IV International Summer School on Cyclodextrins was held in Milano in June 2019. The School  is intended for graduate students, Ph.D students and researchers interested in all the aspects of cyclodextrin chemistry and technology.

The lectures covered several topics on CD and CD inclusion complexes and strongly oriented to teaching and transmission of know-how. SUMBET was represented in the School by Prof. González-Gaitano (teacher) and the PhD students of the group Joan Puig, Leire Goñi and Max Petitjean.

"Guadalupe vuelve a la Facultad de Químicas"
On April 24 a round table was held at the Faculty of Chemistry of the Universidad Complutense de Madrid (UCM) on Guadalupe Ortiz de Landázuri, who will be beatified in Madrid on May 18. The Director of the Department of Chemistry, Gustavo González Gaitano, and the Vice-rector of the Universidad de Navarra, Tomás Gómez Acebo, both alumni from the Faculty of Chemistry, attended the meeting. Dean Prof. Francisco Ortega opened the ceremony by welcoming the numerous attendees and said that it was an honor for the Faculty to have a round table about a former student on the occasion of her beatification, which coincided with the International Year of the Periodic Table, an opportunity to bring Chemistry closer to society (read here the full article)

Mobility of PhD students
Joan Puig has been awarded with a doctoral UN Mobility Grant, aimed to obtaining the mention of international doctoral degree. The stay will take place in the group of Prof. D. Thompson, at Purdue University (US), during the first term of the next academic year. The research will be focused on developing novel bioresponsive carrier systems for drug and gene delivery.

more-news

AGROSYM 2018
The IX International Agriculture Symposium "AGROSYM 2018" was celebrated in Jahorina (Bosnia and Herzegovina), from 4 to 7 October 2018. Prof. Juana Fernández-Rodríguez presented there the communications "Agricultural waste codigestion versus individual anaerobic digestion: effect of temperature" and "Temperature-phased anaerobic digestion of lignocelulosic wastes: artichoke and asparagus". The latter comunication was awarded with the best poster presentation.

PhD dissertation
Beatriz de Diego-Díaz, has recently defended her doctoral dissertation titled "Anaerobic digestion of agricultural wastes: studies of temperature, co-digestion and potential inhibitors", supervised by Dr. Javier Peñas and Dr. Juana Fernández-Rodríguez. The thesis, presented as a compilation of published articles, included the International Doctorate mention with a four-month stay at the Technical University of Denmark (DTU) in 2017 and has received the Cum Laude mention by the examining panel. From our research group and the department, we would like to send our warmest congratulations to the newly-inaugurated doctor.

In the news
Dra. Juana Fernández-Rodríguez  has published an opinion article titled "Women, climate change and vice versa" in Diario de Noticias on 27th October,  about the paper of women in the environment protection. Read here the news.

SANS experiments at ILL
Small angle neutron scattering experiments have been recently carried out at the Institute Laue-Langevin (ILL) with the D33 line (Massive Dynamic Q-Range Small-Angle Diffractometer). The experiments dealt with the structural changes in micellar systems and gels upon a pH-trigger, in collaboration with researchers from UK (KCL), France (ILL) and the Universidad de Salamanca.

Featured publication
A recent paper from SUMBET has been featured among the most cited papers which received in 2017 enough citations to be included in the 1% of the best articles in their respective areas, according to a study from MetricsUN. The contribution, published in Current Pharmaceutical Research, reviews the present research and future prospects of the supramolecular assemblies based on cyclodextrins and polymers as drug carrier systems.

New projects (PIUNA call)
The University of Navarra (PIUNA 2018-2019 call) will fund the project “Aplicaciones de matrices poliméricas de ciclodextrinas sintetizadas mediante procesos sostenibles”. Prof. Javier Peñas and José Ramón Isasi are the main researchers of this project, which will be developed till 2021. In this same call, the project “Diseño y desarollo preclínico de nuevas moléculas híbridas de selenio como agentes antitumorales” has been funded. Prof. Gustavo González and Joan Puig are part of the research team, in collaboration with the Department of Organic Chemistry.

Visiting students
On the 22nd of June took place the public defense of the research works carried out by two visiting students of the University of Lille. Juliette Blardart (left) presented her work "Study of polysaccharide gels", and Emeline Zmuda (center) "Evaluation of the photocatalytic activity of ilmenite". The stay was developed within the frame of an exchange program of the School of Science of the Universidad de Navarra and the University of Lille.

New projects
The project "Functionalization of packaging with new nanoparticulate materials for food industries", whose main researcher is Prof. Itziar Vélaz, has been funded by the "Dirección General de Industria, Energía e Innovación" del Gobierno de Navarra" (program "Ayudas a Centros tecnológicos y Organismos de investigación y difusión de conocimientos para la realización de proyectos de I+D 2018"), since February till December 2018. The project "ANAERObE: Experimental Analysis and use of tannery solid wastes" has been also funded in this call. This is a joint project involving the Department of Chemistry, the School of Architecture, and the company Tenerías Omega, in order to valorize the solid waste generated in the industrial process.

In the media
Prof. Mario Molina, 1995 Nobel Prize laureate in Chemistry for his role in the elucidation of the threat to the Earth's ozone layer by chlorofluorocarbon gases (CFCs), gave a Masterclass on the 6th of June. The session was presented by José Ramón Isasi. Read here the news.

SANS experiments at FRM-II
Profs. González-Gaitano and Javier González Benito (UC3M) have been conducting neutron scattering experiments on the first days of June at the neutron source FRMII of the MLZ (Heinz Maier-Leibnitz Zentrum), in the frame of the project MAT2014-59116-C2-2-R. The experiments, funded by MINECO and the EU, were aimed to ascertain the 3D structure of physical gels formed from supramolecular assemblies of polymeric surfactants.

19th Cyclodextrin Symposium
The 19th edition of the International Cyclodextrin Symposium was celebrated on 27-30 April at Sophia University, Tokio. Profs. Cristina Martínez Ohárriz, Itziar Vélaz, and Joan Puig presented there their communications "Aggregation of glibenclamide-beta-cyclodextrin complexes", "Molecular necklaces of direct and reverse Tetronics and cyclodextrins: a kinetic approach", and "Ketoprofen release studies from insoluble beta-cyclodextrin polymers". The next CD meeting, 6th European Cyclodextrin Conference, will be held at Santiago de Compostela in 2019. SUMBET will participate in the organisation of the conference.

In the media
Article published in Diario de Navarra. 17 de mayo - Día Mundial del Reciclaje. "DIY (Do it yourself): Hazlo por ti y por el medio ambiente" (Prof. Juana Fernández).

Publication
A micrograph showing a detail of a bundle of nanofibers of blow spun nanocomposites based on PSF has been selected as the cover of the November issue of Polymer Physics. The article is a collaboration with the Departamento de Ciencia e Ingeniería de Materiales e Ingeniería Química of the UC3M.