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Polycyclic aromatic hydrocarbons (PAHs) are a family of organic compounds comprising two or more fused aromatic rings which feature manifold applications in modern technology. Among these species, those presenting an open-shell magnetic ground state are of particular interest for organic electronic, spintronic, and non-linear optics and energy storage devices. Within PAHs, special attention has been devoted in recent years to the synthesis and study of the acene and fused acene (periacene) families, steered by their decreasing HOMO–LUMO gap with length and predicted open-shell character above some size. However, an experimental fingerprint of such magnetic ground state has remained elusive. Here, we report on the in-depth electronic characterization of isolated peripentacene molecules on a Au(111) surface. Scanning tunnelling spectroscopy, complemented by computational investigations, reveals an antiferromagnetic singlet ground state, characterized by singlet–triplet inelastic excitations with an experimental effective exchange coupling (Jeff) of 40.5 meV. Our results deepen the fundamental understanding of organic compounds with magnetic ground states, featuring perspectives in carbon-based spintronic devices., Depto. de Química Orgánica, Fac. de Ciencias Químicas, TRUE, pub

AbstractWe report on the synthesis and characterization of atomically precise one‐dimensional diradical peripentacene polymers on a Au(111) surface. By means of high‐resolution scanning probe microscopy complemented by theoretical simulations, we provide evidence of their magnetic properties, which arise from the presence of two unpaired spins at their termini. Additionally, we probe a transition of their magnetic properties related to the length of the polymer. Peripentacene dimers exhibit an antiferromagnetic (S=0) singlet ground state. They are characterized by singlet–triplet spin‐flip inelastic excitations with an effective exchange coupling (Jeff) of 2.5 meV, whereas trimers and longer peripentacene polymers reveal a paramagnetic nature and feature Kondo fingerprints at each terminus due to the unpaired spin. Our work provides access to the precise fabrication of polymers featuring diradical character which are potentially useful in carbon‐based optoelectronics and spintronics., Depto. de Química Orgánica, Fac. de Ciencias Químicas, TRUE, pub

Nanocars are carbon-based single-molecules with a precise design that facilitates their atomic-scale control on a surface. The rational design of these molecules is important in atomic and molecular-scale manipulation to advance the development of molecular machines, as well as for a better understanding of self-assembly, diffusion and desorption processes. Here, we introduce the molecular design and construction of a collection of minimalistic nanocars. They feature an anthracene chassis and four benzene derivatives as wheels. After sublimation and adsorption on an Au(111) surface, we show controlled and fast manipulation of the nanocars along the surface using the tip of a scanning tunneling microscope (STM). The mechanism behind the successful displacement is the induced dipole created over the nanocar by the STM tip. We utilized carbon monoxide functionalized tips both to avoid decomposition and accidentally picking the nanocars up during the manipulation. This strategy allowed thousands of maneuvers to successfully win the Nanocar Race II championship., Funding Agencies|European Research Council [766555]; Comunidad de Madrid [Y2018/NMT-4783, 2018/NMT-4367]; Ministerio de Ciencia e Innovacion [PID2019-108532GB-I00, CTQ2017-86060-P, PID2020-11666RB-I00]; "Severo Ochoa" Programme for Centers of Excellence in RD (MINECO) [2009 00971]; MINECO [BES-2017-082582]; European Union [886314]; Swedish Research Council; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

O objetivo deste trabalho é a verificação da importância da pré-mediação como fase de preparação para a mediação como método adequado de resolução de conflitos. A pesquisa foi realizada por meio de revisão bibliográfica em doutrinas, artigos científicos e legislação. De início, a pesquisa analisou o conflito, seus aspectos negativos e positivos e sua resolução. Em seguida, para compreender o sistema de métodos adequados de resolução de conflitos, houve abordagem sobre acesso à justiça como valor constitucional e sobre o fenômeno da desjudicialização como meio para enfrentar a crise no Poder Judiciário em razão do excesso de demandas judiciais. Tendo como objeto específico o método da mediação, foi necessário um estudo sobre seus aspectos, conceito e a importância do uso de técnicas adequadas, evoluindo para a análise da pré-mediação como etapa prévia à mediação, tratando de sua importância. Como resultado da pesquisa, foi constatado que a pré-mediação é mais que simples fase informativa, e sim, uma adequada fase de preparação das partes envolvidas no conflito para um resultado melhor na mediação.

On-surface synthesis has recently emerged as a powerful strategy to design conjugated polymers previously precluded in conventional solution chemistry. Here, an N-containing pentacene-based precursor (tetraazapentacene) is ex-professo synthesized endowed with terminal dibromomethylene (:CBr2) groups to steer homocoupling via dehalogenation on metallic supports. Combined scanning probe microscopy investigations complemented by theoretical calculations reveal how the substrate selection drives different reaction mechanisms. On Ag(111) the dissociation of bromine atoms at room temperature triggers the homocoupling of tetraazapentacene units together with the binding of silver adatoms to the nitrogen atoms of the monomers giving rise to a N-containing conjugated coordination polymer (P1). Subsequently, P1 undergoes ladderization at 200 degrees C, affording a pyrrolopyrrole-bridged conjugated polymer (P2). On Au(111) the formation of the intermediate polymer P1 is not observed and, instead, after annealing at 100 degrees C, the conjugated ladder polymer P2 is obtained, revealing the crucial role of metal adatoms on Ag(111) as compared to Au(111). Finally, on Ag(100) the loss of :CBr2 groups affords the formation of tetraazapentacene monomers, which coexist with polymer P1. Our results contribute to introduce protocols for the synthesis of N-containing conjugated polymers, illustrating the selective role of the metallic support in the underlying reaction mechanisms., Funding Agencies|European Research Council (ERC CoG ELECNANO) [766555]; Comunidad de Madrid [project QUIMTRONIC-CM] [Y2018/NMT-4783]; Ministerio de Ciencia e Innovacion [PID2019-108532GB-I00]; "Severo Ochoa" Programme for Centers of Excellence in RD (MINECO) [SEV-2016-0686]; European Unions Horizon 2020 research and innovation programme under the Marie Skodowska-Curie grant [886314]; Swedish Research Council; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

One of the main research lines of the Grupo de Electromagnetismo of the Universidad de Cantabria is focused on the study and characterization of planar chiral metamaterial (CMM) structures implemented on printed circuit board technology. The objective of this communication is to analyze the influence of the angle of incidence on the chiral behavior of metamaterial structures. A variation of the split ring resonator (SRR) particle has been used as unit cell of the periodic metamaterials analyzed. From this structure, the effect of the angle of incidence on the chiral response is analyzed, evaluating variations in the geometry that provide different types of interaction between unit cells or between the incident wave and the structure. The SRRs are printed only on one side of the printed circuit board. Fig.1. This way, with normal incidence the structure is achiral. The obtained results show that the angle of incidence is a key parameter for the structure in order to present a chiral behavior. In this case, the chiral behavior is shown as a high difference between the transmission levels of the two eigenwaves (left handed and right handed circular polarized waves), i.e., circular dichroism.

In this work we aim to design circularly polarized flat mirror/reflectarray to work at a dual frequency. The design approach uses a unit cell made by four assymetrical split-ring resonators with an opposite rotation plus an element size variation, a seen in Fig.1 Fig. 1. Proposed structure (unit cell). The SRRs are made on copper on a FR4 substrate. There is a metallic (copper) plane mirror behind the structure. The inner rings have a radius of 5.8 mm (1st and 3rd quadrant) and 5mm (2nd and 4th quadrant). The outer rings have a radius of 10.2mm and 10mm, respectively. As we may see in Fig.2, the proposed structure presents a dual-band circular polarization selection: in the band around 2.97 GHz it absorbs LHCP incident waves while reflecting LHCP incident waves, doing the opposite around 3.28 GHz Fig. 2. Reflection coefficient for a circularly polarized wave normally incident on a structure as shown in Fig.1. The superindexes +/- stand for right-handed/left-handed circular polarized waves.

Canine chronic ulcerative stomatitis (CCUS) is a condition characterized by chronic pain, associated with oral ulceration, inflammation and mucosal necrosis. We report the case of a 5-year-old female Akita Inu canine with sialorrhea, halitosis, oral ulcers, submandibular lymphadenopathy and substantial oral discomfort. After a poor response to conventional scaling and antibiotic treatment, the patient improved when prednisolone was administered at a dose of 1mg / kg daily. Aggressive immunosuppressive treatments and teeth extractions were ruled out, so cellular therapy was started. This study evaluates the effect of allogeneic thawed and expanded canine adipose tissue-derived mesenchymal stem cells (AT-MSCs) therapy in a case of CCUS. Four local injections of AT-MSCs (3.5 to 8×106 cells) were administered every 3–4 weeks under general anesthesia and immediately after dental scaling. A higher dose of AT-MSCs (22×106 cells) was injected 5 months later under the same conditions. After the AT-MSCs treatment, the patient showed an improvement in oral lesions and reduction of oral pain for at least 4 weeks. We concluded that a dose of 1×106 AT-MSCs/kg body weight reduced the symptoms of CCUS for at least one month in this case. To our knowledge, this is the first description of allogeneic AT-MSC therapy on canine chronic ulcerative stomatitis., Kronični ulcerativni stomatitis u pasa (CCUS) obilježava kronični bol, povezan s oralnom ulceracijom, upalom i sluzničnom nekrozom. Ovo je prikaz slučaja petogodišnje ženke pasmine akita inu sa sijalorejom, halitozom, oralnim ulceracijama, submandibularnom limfadenopatijom i supstancijalnim oralnim smetnjama. Nakon slabog odgovora na konvencionalno čišćenje kamenca i antibiotičko liječenje, stanje se poboljšalo s primjenom prednizolona u dozi od 1mg/kg na dan. Odgođena je agresivna imunosupresija i vađenje zubi te je započeta terapija matičnim stanicama. U istraživanju je procijenjen učinak alogenskih odmrznutih i ekspandiranih mezenhimnih matičnih stanica iz adipoznog tkiva (AT-MSCs) u liječenju CCUS-a. Lokalno su primijenjene četiri injekcije AT-MSC-a (3,5 do 8 × 106 stanica) svaka 3 – 4 tjedna pod općom anestezijom i neposredno nakon čišćenja zubnog kamenca. Veća doza AT-MSC-a (22 × 106 stanica) primijenjena je pet mjeseci poslije pod jednakim uvjetima. Nakon liječenja AT-MSC-om došlo je do poboljšanja u cijeljenju oralnih lezija i smanjenju boli tijekom namanje četiri tjedna. Zaključujemo da, u ovomslučaju, doza od 1 × 106 AT-MSC-a po kilogramu tjelesne mase ublažava simptome CCUS-a tijekom najmanje jednog mjeseca. Ovo je prema našim spoznajama prvi opis alogenskog liječenja kroničnog ulcerativnog stomatitisa u pasa AT-MSC-om.

Engineering low-band-gap -conjugated polymers is a growing area in basic and applied research. The main synthetic challenge lies in the solubility of the starting materials, which precludes advancements in the field. Here, we report an on-surface synthesis protocol to overcome such difficulties and produce poly(p-anthracene ethynylene) molecular wires on Au(111). To this aim, a quinoid anthracene precursor with =CBr2 moieties is deposited and annealed to 400K, resulting in anthracene-based polymers. High-resolution nc-AFM measurements confirm the nature of the ethynylene-bridge bond between the anthracene moieties. Theoretical simulations illustrate the mechanism of the chemical reaction, highlighting three major steps: dehalogenation, diffusion of surface-stabilized carbenes, and homocoupling, which enables the formation of an ethynylene bridge. Our results introduce a novel chemical protocol to design -conjugated polymers based on oligoacene precursors and pave new avenues for advancing the emerging field of on-surface synthesis., Funding Agencies|Comunidad de Madrid [Y2018/NMT-4783, S2013/MIT-3007, S2018/NMT]; European Research Council [ERC-320441-Chirallcarbon, ERC-766555-ELECNANO]; Spanish Ramon y Cajal programme [RYC-2012-11133]; MINECO of Spain [FIS 2015-67287-P, CTQ2017-83531-R, CTQ2016-81911-REDT]; Severo Ochoa Programme for Centers of Excellence in RD (MINECO) [SEV-2016-0686]; Praemium Academie of the Academy of Science of the Czech Republic [MEYS LM2015087, GACR 18-09914S]; Operational Programme Research, Development, and Education - European Structural and Investment Funds; Czech Ministry of Education, Youth, and Sports [CZ.02.1.01/0.0/0.0/16019/0000754]; Czech Science Foundation [19-27454X]; Swedish Research Council [642-2013-2080]; Swedish Strategic Research Area in Materials Science on Functional Materials at Linkoping University (Faculty Grant SFO-Mat-LiU) [2009 00971]

[Objective]: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. [Design]: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. [Methods]: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1–10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. [Results]: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and −1.2 (IQR: −2.3 to −0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20–0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21–1.78) years later in those starting with HAZ less than −3 compared with HAZ at least −1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than −1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least −1, there was no association with age. Girls and boys who initiated ART with HAZ at least −1 maintained a similar height to the WHO reference mean. [Conclusion]: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least −1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age.

“Encuentros con la Ciencia” is a multidisciplinary collaborative project with the main objective of making science accessible to society. University and secondary school professors join forces with different agents (institutional and private) and organizations to inform the public about the importance of science in our daily lives. This is possible by involving the scientific community itself to disseminate the scientific knowledge that is currently developed in Spanish research centers. It is achieved through a variety of dissemination activities and scientific practice in two contexts: a general one, with activities opened tom the public, aimed at a heterogeneous audience with different interests in science; and in an educational framework, targeted at students and their teaching staff. The project is based on the structure of the scientific dissemination cycle “Encuentros con la Ciencia”, currently in its fifteenth edition. It is a consolidated structure with headquarters, public, and own resources. The project brings together up to 8 actions: scientific conferences, scientific exhibitions, open workshops on science, Scientific cinema, scientific workshops focused of gifted students (GuíaMe-AC-UMA and “When I grow up I want to be ...”), scientific updates focused on secondary level teachers and Experimenta. We emphasize the media repercussion of this activity that has opened frequent communication channels with the main media of the city (SUR, Cadena SER, Canal SURTV, La Opinión, Malaga Hoy, etc), so that speakers and organizers of "Encuentros con la Ciencia" have in fact, become common sources of scientific information, often even outside the context of the conference. In fact, the media have incorporated "Encuentros con la Ciencia" as a habitual suggestion of the proposals, “Encuentros con la Ciencia” es un proyecto colaborativo multidisciplinar que nace con el objetivo principal de hacer accesible el avance de la ciencia a la sociedad. Profesores universitarios y educadores de secundaria unen esfuerzos con diferentes agentes (institucionales y privados) y organizaciones para informar al público sobre la importancia de la ciencia en nuestra vida cotidiana. Esto se hace posible involucrando a la propia comunidad científica para difundir el conocimiento científico que se desarrolla actualmente en los Centros de investigación españoles. Se logra por medio de una variedad de actividades de difusión y práctica científica en dos contextos: uno general, con actividades abiertas a un público heterogéneo con diferentes intereses por la ciencia; y en el marco educativo, dirigido a los estudiantes y al personal docente principalmente. El proyecto se basa en la estructura del ciclo de divulgación científica “Encuentros con la Ciencia”, actualmente en su decimoquinta edición. Es una estructura consolidada con sede, público y recursos propios. El proyecto reúne 8 acciones: Conferencias científicas, Exposiciones científicas, Talleres abiertos sobre ciencia, Ciencia de cine, Talleres científicos como los GuíaMe-AC-UMA o “Yo de mayor quiero ser...”, actividades de actualización científica y formación del profesorado y Experimenta. Destacamos la repercusión mediática de esta actividad que ha abierto canales de comunicación con los principales medios de comunicación de la ciudad (Cadena Ser, Canal Sur, La Opinión, Málaga Hoy, etc), de manera que ponentes y organizadores de Encuentros con la Ciencia se han convertido, de hecho, en fuentes expertas habituales de información científica, a menudo incluso fuera del contexto de las jornadas. Por todo ello, se ha conseguido que los medios de comunicación hayan incorporado a "Encuentros con la Ciencia" como una referencia en divulgación de la ciencia