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King penguins (Aptenodytes patagonicus) are colonial seabirds presenting an extraordinary breeding cycle. Parents take over 14 months to raise a single chick to independence, upon which fledglings depart at sea for more than a year. Juveniles often return to the colony within the three austral summers following departure, and before the age of first reproduction (around 5–6 years old), possibly to acquire the essential skills involved in breeding. Little to nothing is known on the acquisition of parental behaviour. Here, we report an anecdotal, yet highly unusual, observation of chick–chick feeding behaviour in this species. The behaviour is highly unusual in that two non-sibling chicks, not yet independent, and hatched at different times (early and late) of the same breeding season were observed, the older chick feeding the younger one. Whereas alloparental feeding is known to occur in this species, this is the first reported observation of a chick–chick feeding event. This unusual behaviour raises the question of whether the early social environment plays a role in the acquisition of essential parenting skills in this species.

Electrodeposited iridium oxide (K1.7IrO0.8 (OH)2.2 × 1.8 H2O; also called IrOx) is among the best substrates for neural growth, decreasing impedance and stimulating cell growth, when used as a connected electrode. Without direct contact, it has been proven to stimulate neurons through a bipolar mechanism related to the conducting character of the material in the presence of remote electric fields. The remote wireless electrostimulation that arises from it is of large significance in clinical applications. Ionic intercalation simultaneous with iridium oxidation state changes at the induced IrOx cathode and the formation of a redox and ionic gradient at the IrOx substrate is envisaged as the most probable explanation for the observed effects on neural cell growth. This work shows the iridium state gradient using X-ray absorption spectroscopy (XAS) with significant electrochemical features and relaxation times that allow for a persistent effect in the material even after the electric field creating the induced dipole is switched off. It also shows correlated intercalated sodium gradients observed by semiquantitative energy-dispersive X-ray (EDX) analysis data. The bipolar effect is proven and yields new evidence for the behavior of other biocompatible neural growth substrates., The authors thanks financing from the Ministry of Science of Spain (MAT2015-65192-R, and RTI2018-097753-B-I00), and Severo Ochoa Program (CEX2019-000917-S). LlA thanks the Ramon y Cajal Program contract (RYC-2013-12640). ALBA synchrotron experiments were performed under Grant 2020024334.

Prickly pear is a sweet succulent plant resistant to arid land conditions and because of these attributes it has been used as an emergency livestock feed, especially during the winter and spring seasons.

Uveal melanoma (UM) is the most frequent intraocular cancer in adults and 50% of patients develop liver metastases for which no treatment is effective. According to The Cancer Genome Atlas, 92% of cases are characterized by early mutations in two genes coding for alpha subunits of G protein coupled receptors (GPCR): G protein subunit alpha q (GNAQ) or 11 (GNA11). These mutations are mostly found in the codon Q209 causing a constitutive activation of different signaling pathways linked to cellular proliferation such as MAPK and PKC. Furthermore, a bi-allelic inactivation of the BRCA1 associated protein-1 (BAP1) is found in 83% of metastatic UM and causes a loss of function of this protein. Our hypothesis is that the genes essential for the survival of mutant UM cells will be ideal therapeutic targets. Using CRISPR/Cas9 technology, we engineered GNAQ/11 and BAP1 mutant isogenic cell lines derived from wildtype UM cells or choroidal melanocytes (CM) to better understand the molecular mechanisms involved in UM development. We have designed three ribonucleoprotein complexes (RNPs) composed of single-guide RNA (sgRNA) and Streptococcus pyogenes Cas9 (spCas9) specific to the GNAQ/11 and BAP1 genes. This allowed to target the DNA sequence on the exon 5 of these proteins to induce a double-strand break. To introduce the desired mutations Q209L in GNAQ/11 or C91G in BAP1, we have also designed DNA templates called single-strand oligo DNA nucleotides (ssODNs) that were co-transfected with respective RNPs by electroporation into UM cells (Mel285) or CM and favorized the homologous recombination (HR) during DNA repair to knock-in these mutations. After a few days, we genotyped the clones by Sanger sequencing and expanded those of interest into cell lines. We obtained an electroporation efficiency of 50% for CM and 70% for Mel285 using an eGFP plasmid. The first CRISPR transfections showed a mean edition of 20-60% of targeted regions with 4% HR. To increase our percentage of HR, we have also used the Prime Editing method; nine plasmids per mutation have been designed and constructed. The first transfection tests in HEK293T cells are currently underway. We obtained three KO cell lines: Mel285GNAQ-KO, Mel285GNA11-KO and Mel285BAP1-KO. We saw no morphologic changes. A decrease in the proliferation and metabolic activity was observed in Mel285GNAQ-KO and Mel285BAP1-KO cell lines in comparison to the wildtype cells. Furthermore, an increase of phosphorylated ATF2/7 was noted in Mel285GNAQ-KO and Mel285GNA11-KO cell lines by western blotting. A better understanding of the altered pathways in our GNAQ/11 or BAP1 mutant isogenic cell lines will help to identify new drugs targeting specifically metastatic UM cells. Citation Format: Aurélie Fuentes-Rodriguez, Andrew Mitchell, Joël Rousseau, Jacques P. Tremblay, Solange Landreville. GNAQ/GNA11 and BAP1 mutant isogenic cell lines engineered by CRISPR/Cas9 gene editing to model ocular melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2610.

Aquesta tesi s'enfoca a nous aspectes d'electroquímica sense fil bipolar no desenvolupats prèviament. La electroquímica bipolar fa possible la generació d'un potencial induït a un material conductor immers (elèctrode bipolar). Tot això sense que existeixi contacte directe per cable, gràcies a la inducció d'un dipol oposat al camp extern imposat entre les bores del material. Això fa possible generar reaccions electroquímiques a l'ànode i al càtode induïts del material immers i, a més, obre la porta a una gran varietat d'aplicacions electroquímiques sense fil. La generació de pols oposats i la electroquímica que s'associa a ells dóna lloc a canvis tant a les propietats de la cel·la global com a la dels materials immersos. Això, alhora, pot donar lloc a canvis a les propietats del material o induir, com es va reportar anteriorment, fenòmens d'electroestimulació neuronal. En aquest sentit, a aquest treball s'han observat diversos punts experimentals. La presència d'una o vàries peces conductores a l'electròlit genera una caiguda notable de la resistència de la cel·la electroquímica, inclús sense percolació, degut a la reorganització iònica generada pels dipols generats. De la mateixa manera, disminueix la resistència de transferència de càrrega i permet una mediació redox, gràcies a la conversió química de les espècies reduïdes al càtode adjacent i contigu o viceversa, en el que es pot definir como un efecte en cascada. Les reaccions presents a l'elèctrode bipolar sense contacte depenen del voltatge extern aplicat, de la configuració geomètrica (incloent la posició al camp, la forma i/ o el volum d'ocupació del material), del electròlit i de la pròpia reactivitat del material. Així, un metall noble resulta inert mentre que el dissolvent o les espècies contingudes en ell s'oxiden o es redueixen a cada un dels pols del material immers. Un metall com el coure, en medi alcalí, pateix una anodització induïda que, tal com hem observat, dóna lloc a franges d'òxids i hidròxids amb estats d'oxidació oscil·lants degut als canvis de resistència que modifiquen els dipols induïts. Si el material immers permet la intercalació redox, essent un conductor iònic-electrònic, les observacions amb resolució espacial o operando mostren la intercalació d'ions Na+ presents al medi (al càtode induït) i la seva propagació cap a l'ànode degut a canvis de resistència, generant un material en gradient redox. Aquest gradient pot ser el responsable del gran efecte que els elèctrodes bipolars, l'IrOx i el PEDOT:PSS tenen al creixement neuronal. En ambdós casos existeix una relaxació del gradient de diferents escales de temps. La mobilitat aniònica al CoN permet, de la mateixa manera, la reacció de reducció a Co metàl·lic i, per tant, la generació de ferromagnetisme de magnitud notables a baixos potencials aplicats. Depenent de la posició geomètrica del material al camp elèctric es forma un material en gradient o homogeni i, per tant, el ferromagnetisme es volàtil o permanent. Cada un dels resultats ofereix un nou paradigma en diversos camps d'aplicació, des de la electroestimulació ja assajada, a sistemes d'emmagatzematge d'energia, dispositius electrònics o magneto-iònics, entre d'altres. S'ha augmentat la comprensió dels fenòmens implicats de vegades molt complexos com es el cas de la oxidació del coure. Esta tesis se enfoca en nuevos aspectos de electroquímica inalámbrica bipolar no desarrollados previamente. La electroquímica bipolar hace posible la generación de un potencial inducido en un material conductor inmerso (electrodo bipolar). Todo ello sin que exista contacto directo por cable, gracias a la inducción de un dipolo opuesto al campo externo impuesto entre los bordes del material. Ello hace posible generar reacciones electroquímicas en el ánodo y cátodo inducidos del material inmerso y, además, abre una puerta a una gran variedad de aplicaciones electroquímicas inalámbricas. La generación de polos opuestos y la electroquímica que se asocia a ellos da lugar a cambios tanto en las propiedades de la celda global, así como en los materiales inmersos. Esto a su vez puede dar lugar a cambios en las propiedades del material o inducir, como se reportó anteriormente, fenómenos de electroestimulación neuronal. En ese sentido, en este trabajo se han observado varios puntos esenciales. La presencia de uno o varias piezas conductoras en el electrolito genera una disminución notable de la resistencia de la celda electroquímica incluso sin percolación posible, debido a la reorganización iónica generada por los dipolos formados. Asimismo, disminuye la resistencia de transferencia de carga y permite una mediación redox gracias a la conversión química de especies reducidas en el ánodo contiguo adyacente o viceversa, en lo que se puede definir como un efecto en cascada. Las reacciones presentes en el electrodo bipolar sin contacto dependen del voltaje externo aplicado, de la configuración geométrica (incluyendo posición en el campo, forma y volumen de ocupación del material), del electrolito y de la propia reactividad del material. Así un metal noble resulta inerte mientras que en sus polos se oxida y reduce respectivamente el disolvente o las especies que contiene. Un metal como el cobre, en medio alcalino, sufre una anodización inducida que, tal como hemos observado, da lugar a franjas de óxidos e hidróxidos con estados de oxidación oscilantes debido a los cambios de resistencia que modifican los dipolos inducidos. Si el material permite intercalación redox, siendo un conductor mixto iónico-electrónico, las observaciones con resolución espacial u operando muestran la intercalación de iones Na+ presentes en el medio en el cátodo inducido y su propagación hacia el ánodo, debido a cambios de resistencia, lo que genera un material en gradiente redox. Este gradiente puede ser el responsable del gran efecto que los electrodos bipolares, el IrOx y el PEDOT:PSS, tienen en el crecimiento neuronal. En ambos casos existe una relajación del gradiente de distintas escalas de tiempo. La movilidad aniónica en CoN permite, asimismo, la reacción de reducción a Co metálico y, por tanto, la generación de ferromagnetismo de magnitud notable a bajos potenciales. Dependiendo de la posición geométrica del material en el campo eléctrico, se forma un material en gradiente o homogéneo y, por tanto, el ferromagnetismo es volátil o permanente. Cada uno de los resultados ofrece un nuevo paradigma en diversos campos de aplicación, desde la electroestimulación ya ensayada, a sistemas de almacenamiento de energía, dispositivos electrónicos o magneto-iónicos, entre otros. Pero sobre todo como línea base, se ha aumentado la comprensión de los fenómenos implicados, a veces muy complejos como el caso de la oxidación del cobre. This thesis focusses on new aspects of bipolar wireless electrochemistry not previously developed. Bipolar electrochemistry occurs when an induced potential is generated among poles on an immersed conducting material (bipolar electrode) using driving external electrodes. This without a cable connection with the bipolar electrode, thanks to the induction of a dipole opposite to the external field imposed between the edges of the material. This makes it possible to generate electrochemical reactions in the induced anode and cathode of the immersed material, and opens the door to a wide variety of wireless electrochemical applications. The creation of opposing poles in the immersed material and the associated electrochemistry cause changes both in the global cell and in the material, which in turn may change the final phases and properties, and induce phenomena like previously observed wireless neural electrostimulation. In this work, several essential highlights have been observed and studied. The presence of one or several conducting pieces immersed in the electrolyte decreases substantially the resistance of the electrochemical cell, even without electron percolation. This is due to the dipole formation and ionic redistribution in the cell. In addition, a decrease in charge transfer resistance is observed, and additional pathways found for redox mediation, thanks to the possible conversion of reduced species on the adjacent induced anode, or vice versa, in what may be described as a cascade effect. The electrochemical reactions at the bipolar electrode depend on the external applied voltage, geometrical configuration (including the position within the field forces, shape and volume of occupation of the material), the electrolyte and the materials chemical reactivity. Thus, a noble metal is inert and at its induced poles reactions occurring correspond to the solvent and redox species present in it. A metal like copper, in alkaline media, undergoes an induced anodization that, as we have observed, yields a number of oxide and hydroxide stripes perpendicular to the field, with oscillating oxidation states due to the evolution of resistance of the metal surface, which in turn modify the induced dipoles. If the material allows redox intercalation processes (being a mixed ionic electronic conductor), the local resolution studies ex situ or in operando modes show intercalation of Na+ present in the media, at the induced cathode, and its propagation towards the induced anode, due to changes in resistance. That renders eventually a redox gradient material. This gradient maybe responsible of the great effect that IrOx PEDOT:PSS, bipolar electrode, have on neuronal wireless stimulation. In both cases, a relaxation of the gradient exists at different time scales. The anionic mobility in CoN allows also the reduction reaction to metallic Co at the induced cathode and, therefore, the generation of ferromagnetism with a significant magnetization, at low potentials in Wireless conditions. Depending on the geometry position of the material vs the electric field, a gradient material or a homogeneous one is formed and, therefore, such ferromagnetism may be volatile or permanent. Each of the results found offer a new paradigm related Wireless applications, from electrostimulation already described to energy storage systems, electronics and magneto-ionic devices and others. And above all, a new comprehension of the phenomena involved has evolved, even in very complex systems like copper oxidation, and will continue opening possibilities.

El trabajo que se presenta a continuación es para optar al título de ingeniero electrónico y hace parte de la opción de grado tomada con la especialización en Administración y Gerencia de los sistemas de la calidad, cursados en la universidad Santo Tomás seccional Tunja, en el cual se desarrolló la planificación estratégica del sistema de gestión de calidad para la empresa CONECTA Comunicaciones S.A.S, basado en la NTC ISO 9001:2015. The work presented below is to apply for the title of electronic engineer and is part of the degree option taken with the specialization in Administration and Management of quality systems, studied at the Santo Tomás Tunja sectional university, in which The strategic planning of the quality management system was developed for the company CONECTA Comunicaciones SAS, based on the NTC ISO 9001: 2015. Ingeniero Electronico Pregrado

Advances in science and technology, especially in bioprospecting and biomimetics, have provided solutions to everyday problems over time. Through bioengineering, research and the discovery of the mechanisms present in nature for the production and functionality of adhesives, different materials and substances capable of imitating the role of their analogs in nature have been developed, which generates positive consequences in the area of the medical, textile, wood industry, among others. In this review, we present some researches and discoveries that have been made, which focus on the way in which adhesives produced by organisms found in nature are made, such as: marine organisms, plants, land organisms, insects, among others. In addition, different types of adhesives that exist and how they can be produced synthetically to be oriented to several industrial applications are mentioned, too.