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Background Background: The feasibility of anti-TNF discontinuation in inflammatory bowel disease (IBD) must be proven in clinical trials including patients in clinical, endoscopic, and radiologic remission at the time of anti-TNF withdrawal to make recommendations for clinical practice. Aims Primary: to compare the rates of clinical remission at 1 year in patients who discontinue anti-TNF treatment vs. those who continue treatment. Secondary objectives: to know the effect of anti-TNF withdrawal on relapse-free time, mucosal healing and safety; and to identify predictive factors for relapse. Methods Prospective, quadruple-blind, multicentre, randomised, controlled trial. Patients with ulcerative colitis (UC) or Crohn’s disease (CD) in clinical remission for > 6 months were randomised to maintain anti-TNF treatment [maintenance arm (MA)] or to withdraw it [withdrawal arm (WA)]. Patients who were on infliximab (IFX) received IFX 5 mg/kg or an intravenous placebo every 8 weeks, while patients on adalimumab (ADA) received subcutaneous ADA 40 mg or placebo every other week. Patients were followed-up until month 12 or up to the time of clinical relapse, whichever came first. Inclusion and exclusion criteria, trial scheme and definitions are summarized in figures 1a, 1b and 1c. Results were analysed by intention-to-treat (ITT) and by per-protocol (PP). Local investigators were blinded to faecal calprotectin (FC) and IFX and ADA trough levels. On-site monitoring was performed to assess data quality. Results 159 patients were screened, from whom 140 were randomised and comprised the ITT cohort: 70 allocated to the MA and 70 to the WA. Fifteen patients dropped out before the end of follow-up (12 months or relapse), leaving 63 patients in the MA and 62 patients in the WA for the PP analysis. The characteristics of patients in the MA and WA were similar (figure 2). The proportions of patients who maintained clinical remission -59/70 (84%), 95% confidence interval (CI)=74-92% in the MA vs. 53/70 (76%), 95%CI=64-85% in the WA- and who remained without significant endoscopic lesions at the end of follow-up were similar between groups (figures 3a, 3b, 3c). Only the proportion of patients with FC >250 mg/g was higher in the WA at the end of follow-up (figure 3d). Maintenance of clinical remission was no different between groups (figure 4). The same percentage of patients in both groups had at least one adverse event (69%). The proportion of patients with serious adverse events was also similar between groups (4% in MA vs. 7% in WA). Conclusion Anti-TNF withdrawal in selected IBD patients in clinical, endoscopic, and radiologic remission could be feasible without an increase in the risk of clinical relapse. Long-term follow-up of these patients is warranted.

Background The use of ustekinumab (UST) and vedolizumab (VDZ) as first line therapy for inflammatory bowel disease (IBD) is increasing due to safety reasons and contraindications of anti-TNFs. However, there are no studies evaluating their efficacy and safety in clinical practice under these circumstances. Thus, our aims were to describe bionaïve patients’ characteristics starting VDZ or UST and to evaluate treatment persistence of these drugs and their safety profile in this scenario. Methods Descriptive, retrospective and multicenter study based on the ENEIDA registry (a large, prospectively maintained database of the Spanish Working Group in IBD –GETECCU). All IBD patients never exposed to biological agents who started VDZ or UST as first-line biological treatment were identified. Results Out of 29,450 IBD patients ever exposed to biological drugs included in the ENEIDA registry, 924 patients met the inclusion criteria. Of these, 366 (40%) started UST and 558 (60%) VDZ as first line biological therapy. UST group: 48% women, 90% Crohn's disease (43% ileal; 13% colic; 43.5% ileocolic; 31% upper gastrointestinal involvement; 25% stricturing behaviour; 12% penetrating, 18% perianal disease), 10% ulcerative colitis (74% extensive, 17% left-sided, 9% proctitis), 27% had extraintestinal manifestations (EIM). Median age at the beginning of UST was 57 years (IQR 57-70), 17% patients had a past history of malignancy and, 34% had associated comorbidities. UST indication was luminal activity except in 2% for perianal disease and 5% for EIM. At the end of follow-up (median 14 months [IQR 6-30]), 12 patients (3.3%) developed adverse effects (AEs) that led to treatment discontinuation in the majority of them (92%). VDZ group: 44% women, 42% Crohn's disease (44% ileal; 18% colic; 38% ileocolic; 25% upper gastrointestinal involvement; 28% stricturing behaviour; 13% penetrating; 7% perianal disease), 58% ulcerative colitis (50% extensive, 42% left-sided, 8% proctitis), 17% had EIM. The median age at the beginning was 61 years (IQR 48-71), 24% had past history of malignancy and, 34% associated comorbidities. The indication was exclusively luminal activity. At the end of follow-up (median 21 months [IQR 8-36]), 36 patients (6.5%) had AEs, that lead to treatment withdrawal in 67% of them (24 patients). Cumulative treatment persistence rates were 78%, 60% and 50% for VDZ and 85%, 75% and 66% for UST at 12, 24 and 36 months, respectively (P Conclusion In clinical practice, VDZ and UST are used first-line particularly in elderly patients with comorbidities. Both treatments have a good safety profile and a high persistence of treatment, being superior for ustekinumab.

Background Oral corticosteroids remain as the first-line treatment for moderately active ulcerative colitis (UC). In controlled studies, they achieved clinical remission in 30-60% of patients at 30 days. In severe systemic diseases, intravenous bolus administration of methyl-prednisolone accelerates the clinical response and increases the therapeutic efficacy of corticosteroids. Aims To assess the additive effect of IV boluses of methyl-prednisolone in an outpatient Schedule on the remission rate of moderately active UC. Methods Randomized, controlled, open study. Inclusion criteria: 1) moderately active (complete May 6-10) distal or extensive UC; 2) never exposed to immunosuppressants or biologicals; 3) without corticosteroid therapy within the last 6 months. Randomization to oral prednisone 60mg/day (ORAL arm) or the same regimen preceded by intravenous boluses of 500mg methyl-prednisolone for 3 days (BOLUS arm). Primary endpoint: clinical and endoscopic remission at week 8 as defined by a complete Mayo score 1. Results are expressed in frequencies, medians and interquartile range. Results 75 patients (39 ORAL, 36 BOLUS) were included, 24% at diesease onset, 49% extensive UC, 68% were on maintenance with oral 5ASA, and 31% had ever received systemic corticosteroids. At baseline, complete Mayo score was 9 (7-9), with C-reactive protein 9.25 mg/L (3.85-20.17) and fecal calprotectin 1430 ug/g (501-2702), with no differences in the baseline clinical-epidemiological characteristics between both treatment arms. At 8 weeks, 37% of patients achieved clinical-endoscopic remission (47% BOLUS vs 28% ORAL; p=0.089), 52% mucosal healing -Mayo endoscopic subscore Conclusion The addition of three intravenous megaboluses at the beginning of a conventional regimen of oral prednisone achieves a non-significant increase in clinical-endoscopic remission rates at the end of corticosteroid treatment in patients with moderately active UC.

Background Background: It has been postulated that early treatment of inflammatory bowel disease (IBD) is associated with a better long-term response. In Catalonia, the early detection program for colorectal cancer (EDPCRC) has been active since 2010, and was extended to the entire Catalan territory in 2015. The aim of this study is to describe the natural history of IBD asymptomatic diagnosed through the EDPCRC in Catalonia. Methods Methods: Observational, longitudinal and retrospective study of patients with IBD detected in the EDPCRC with a positive faecal immunological test in 21 centers in Catalonia between 2010 and 2019. Data was collected from the clinical histories. Results Results: 237 patients were identified; 35 patients had symptoms before endoscopy and were excluded from the study, finally 200 patients were diagnosed with asymptomatic IBD during the EDPCRC; 109 ulcerative colitis (54.5%), 63 Crohn's disease (31.5%) and 28 unclassifiable colitis (14%). 35.5% were women (n=71) with an average age of 60 years (range 49-79). Of the asymptomatic, 40.5% developed symptoms (n=81), being diarrhea the most frequent (n=45; 55.6%). The median time to first symptom was 368 days. Treatment was prescribed in 74.5% (n=149) of the patients. Mesalazine was the most frequently prescribed drug (n=130). The main reason for prescribing it was endoscopic activity (n=107), followed by the appearance of symptoms (n=39) and the biochemical activity (n=9). Only 19 patients (9.5%) required biological treatment (5 infliximab, 10 adalimumab, 2 vedolizumab and 2 ustekinumab). 4 patients (2%) required surgery. Conclusion Conclusion: Less than half of patients diagnosed with IBD at a preclinical stage develop symptoms after the first year of follow-up. Only 9.5% require biological treatment and 2% surgery. Three-quarters of patients are prescribed treatment; the most used was mesalazine.

The improvement of high temperature materials with lower heat transfer coefficients lead to the development of thermal barrier coatings (TBCs). One of the most widely used materials for thermal barrier coatings is Y2O3 stabilized ZrO2 (Y-TZP) because of its excellent shock resistance, low thermal conductivity, and relatively high coefficient of thermal expansion. The aim of this work is to study the TBCs mechanical behavior with the addition of SiC into the suspension of Y-TZP/Al2O3 by acoustic emission (AE). Additionally, a microstructural analysis and a finite elements model were carried out in order to compare results. The coatings were made by suspension plasma spray (SPS) on metal plates of 70 &times, 12 &times, 2 mm3. An intermetallic was deposited as a bond coating, followed by a coating of Y-TZP/Al2O3 with and without 15 wt.% SiC, with thicknesses between 87 and 161 &mu, m. The AE becomes a fundamental tool in the study of the mechanical behavior of thermal barriers. The use of wavelet transforms streamlines the study and analysis of recorded sound spectra. The crack generation arises at very low stress levels.

Background The development program (UNIFI) has shown promising results of ustekinumab in ulcerative colitis (UC) treatment that should be confirmed in clinical practice. Aims Primary: to evaluate the durability of ustekinumab treatment in UC patients in clinical practice. Secondary: to assess the short-term response (at week 16) and the long-term effectiveness (at maximum follow-up) and to assess the safety of ustekinumab in clinical practice. Methods Patients included in the prospectively maintained ENEIDA registry who received at least one intravenous dose of ustekinumab due to active UC [Partial Mayo Score (PMS) >2] were included. Clinical activity and effectiveness were defined based on PMS. Results 95 patients were included (table 1). At week 16, 53% of patients had clinical response (including 35% of patients in remission) (figure 1). In the multivariate analysis, elevated serum C-reactive protein was the only variable significantly associated with clinical remission. Long-term remission is represented in figure 2. 36% of patients discontinued the treatment with ustekinumab during a median follow-up of 31 weeks. The probability of maintaining ustekinumab treatment was 87% at week 16, 63% at week 56, and 59% at week 72 (figure 3); primary failure was the main reason for ustekinumab discontinuation. No variable was associated with risk of discontinuation. Three patients reported adverse events; one of them had a fatal severe SARS-CoV-2 infection. Conclusion Ustekinumab is effective both in the short and the long-term in real-life, even in a highly refractory cohort. Higher inflammatory burden at baseline correlated with lower probability of achieving remission. Safety was consistent with the known profile of ustekinumab.

Ceramic substrates were metallized with a Ni-Mo-P electroless coating and further modified with a polypyrrole (PPy) coating by the electrodeposition method. The properties of the polypyrrole coating were studied with the addition of a graphene oxide (GO) nanomaterial prior to the electrodeposition and its reduction degree. Fourier Transform Infrared Spectroscopy, Field-Emission Scanning Electron Microscopy, Raman spectroscopy and cyclic voltammetry were employed to characterize the properties of the coatings. The results indicated the successful synthesis of conductive electrodes by the proposed approach. The electrodeposition of PPy and its charge storage properties are improved by chemically reduced GO. The surface capacitive contribution to the total stored charge was found to be dominant and increased 2&ndash, 3 fold with the reduction of GO. The chemically reduced GO-modified PPy exhibits the highest capacitance of 660 F g&minus, 1 at 2 mV s&minus, 1, and shows a good cyclability of 94% after 500 charge/discharge cycles. The enclosed results indicate the use of an NiMoP electroless coating, and modification with a carbon nanomaterial and conducting polymer is a viable approach for achieving functional ceramics.

Nanostructured polypyrrole coating was applied on carbon paper via simple dip-coating and electrochemical approach. Hybridization with nanocarbon materials (graphene oxide (GO) and multi-walled carbon nanotubes (MWCNTs)) and their effect as an anchoring hybrid layer for the growth of polypyrrole towards improving electrochemical properties are studied. The loading of each component and their w/w ratio were evaluated. Fourier transform infrared spectroscopy, field emission scanning electron microscopy, and Raman spectroscopy were employed to characterize the properties of the coatings. The electrochemical properties were investigated by cyclic voltammetry. The results indicated the electrodeposition of polypyrrole is enhanced by the addition of MWCNTs to the GO layer due to the formation of a hierarchical network. The electrochemical performance of the modified electrode was shown to be highly dependent on the employed w/w ratio, reaching a capacitance value of about 40 mF cm&minus, 2 for a carbon paper substrate modified with GO:MWCNT in a w/w ratio of 1:2.5 and PPy layer deposited by cyclic voltammetry for 30 cycles. The contribution to total stored charge was found to be primary from the inner capacitance component of about 95.5% contribution.

Background Oral corticosteroids remain the treatment of choice for moderately active flares of ulcerative colitis (UC). In early controlled studies, oral corticosteroids achieved clinical remission rates of, 30–60% at, 30 days. Some small prospective studies observed that the administration of high-dose intravenous bolus of methyl-prednisolone accelerated their therapeutic action and increased the rate of clinical response. We aimed to evaluate if the outpatient administration of intravenous, high-dose, methyl-prednisolone bolus increases the efficacy of a conventional course of oral prednisone in moderately active UC. Methods Prospective, multicentre, controlled, randomized, open-label study comparing the therapeutic efficacy of a standard oral prednisone schedule with the same schedule preceded by a three-day regimen of high-dose intravenous bolus of methyl-prednisolone. Inclusion criteria were: Moderately active, left-sided/extensive UC (total Mayo score, 6–10), with no prior exposure to immunosuppressants or biologics, and no corticosteroid treatment in the last, 6 months. Patients were randomized to oral prednisone, 60mg/day (ORAL group) or the same schedule preceded by intravenous bolus of, 500mg of methyl-prednisolone for three consecutive days (BOLUS group), stratified by the baseline use of oral, 5ASA and UC onset. Early clinical response was defined as the reduction of the baseline partial Mayo Score (pMS) by at least three points with at least a decrease by, 1 point in rectal bleeding and with an absolute value of, 0 or, 1, seven days after starting treatment (EUDRA CT:, 2016-001170-15)(Clinicaltrials.gov: NCT02921555) Results In all, 71 patients (38 ORAL, 33 BOLUS) were included. At baseline, the median pMS was, 6 (IQR, 5–7). In, 21% of the patients, the index flare was the onset of UC and, 68% had never received systemic corticosteroids for UC. There were no differences in baseline clinical and demographic features between the two study groups. At day, 7, the proportion of patients fulfilling early clinical response criteria was similar in both groups (BOLUS, 63% vs. ORAL, 58%; p = 0.6), but a significantly greater reduction in pMS at day, 3 (-3.4. vs -1.7; p Conclusion The addition of three high-dose intravenous bolus of methyl-prednisolone to a standard schedule of oral corticosteroids achieves a faster and more intense response in the short-term in moderately active flares of UC, but it does not increase the clinical response rate at seven days. The impact of these effects on the medium-term outcomes is still to be assessed.

In this paper, ZnO electrodeposition was studied with the presence of graphene oxide (GO) exploited as a possible structure-directing agent. The effect of deposition potential and duration on the morphology and structure of ZnO was analyzed. The morphology and structure of the hybrids was analyzed by Raman spectroscopy, X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). The Raman results indicate a successful modification of ZnO with GO sheets and a hybridization threshold of 10 mg L&minus, 1 by the evolution of the defect related band of ZnO at 580 cm&minus, 1. The morphology results show that a low GO content only slightly influences the morphology and orientation of ZnO nanostructures while a high content as 10 mg L&minus, 1 changes the morphology in nanoplates and growth orientation to lateral. The results show that while GO participated in the deposition reaction, it has a two-fold role, also by structure-controlling ZnO, indicating that the approach is valid for the use of GO as a structure-directing agent for the fabrication of ZnO nanostructures by electrodeposition with varying morphologies and orientations.

Novel hybrid core-shell nanoarchitectures were fabricated by a simple two-step electrochemical approach: first ZnO nanorod core was electrodeposited from Zn(NO3)2 solution; further, the core nanoarray was coated with a shell based on polypyrrole hybridized with graphene oxide by electropolymerization. The properties of the core/shell nanoarchitectures were studied as a function of the core properties induced by electrodeposition parameters. The ZnO nanostructures showed improved crystallinity and c-axis preferred orientation with increasing cathodic deposition potential while the increased deposition duration resulted in a morphology transition from nanorod to pyramidal shape. The electrochemical activity of the core/shell arrays was found to increase with the deposition potential of ZnO core but decreased when morphology changed from nanorod to pyramid shape. The photocatalytic results showed improved activity for the core/hybrid shell nanoarrays with respect to ZnO and ZnO/PPy ones. The degradation rate for methylene blue decreased with prolonged deposition duration of the core. The obtained results highlight the importance of electrochemical tuning of ZnO-based core/shell nanoarrays for improved performance in electrochemical and photocatalytic applications.

Background Ustekinumab has shown promising results in ulcerative colitis (UC) in the development program (UNIFI) that should be confirmed in clinical practice. Our aim was to evaluate the effectiveness and safety of ustekinumab in UC in real life. Methods Patients included in the prospectively maintained ENEIDA registry that received at least 1 dose of ustekinumab intravenously due to active UC were included. Clinical activity and effectiveness were defined based on Partial Mayo Score (PMS). The short-term response was assessed at week 8 and 16. The last-observation-carried-forward method was used in patients that stopped ustekinumab treatment before week 8 or 16. Variables associated with short-term remission were identified by logistic regression analysis. Data quality was assessed by remote monitoring. Results Forty-seven patients were included (Table 1); all of them had been previously exposed to biologic agents (70% to >2): 100% to anti-TNF and 83% to vedolizumab. A total of 26% had been exposed to tofacitinib. Seventeen patients (36%) had response at week 8 [3 of them (6%) had remission]; 16 patients (34%) had response at week 16 [5 of them (11%) had remission] (Figure 1). There was a statistically significant decrease in C-reactive protein (CRP) concentration during the induction only in patients with a response at week 16 (Figure 2). The proportion of patients with CRP elevated at baseline and at week 8 was higher among non-responders at week 16 (Table 2). In the multivariate analysis, higher PMS at week 8 [odds ratio (OR) = 0.5; 95% confidence interval (CI) = 0.3–0.9)] and CRP over the upper normal limit at week 8 (OR = 0.1; 95% CI = 0.01–0.8) were associated with lower probability of response at week 16; steroids during induction increased the probability of response at week 16 (OR = 8; 95% CI = 1–71). Of patients without response at week 8, only 7% achieved response at week 16. Seventeen out of 31 patients continued ustekinumab beyond week 16, despite being non-responders. Of these 17 patients, 4 reached remission after the third dose, 1 after the fifth and 1 after the seventh one. There were 2 infections, one of them with fatal consequences (in a patient under steroids and tacrolimus due to renal transplant). Conclusion Ustekinumab shows benefit in some UC patients in real practice, even in a very refractory cohort in which the drug was prescribed as last resort. Patient status at week 8 seems to be a good predictor of response after the induction. Safety was consistent with the known profile of ustekinumab.

Resumen Introduccion Hay pacientes con enfermedad inflamatoria intestinal (EII) que tienen urgencia para defecar, lo que afecta su calidad de vida. Por este motivo se creo el proyecto «No puc esperar», el cual intenta procurarles un acceso rapido y gratuito a los lavabos, donde lo necesiten. Despues de un ano en funcionamiento en Girona como prueba piloto, pretendemos evaluar la eficiencia y la eficacia del proyecto a traves de una encuesta. Materiales y metodos Estudio observacional. Los analisis fueron realizados a traves de una encuesta. La encuesta fue dividida en 3 items, evaluando percepcion del usuario, percepcion del paciente hacia el publico y evaluacion de la eficacia de la tarjeta. Resultados Desde enero de 2014 hasta enero de 2015 se entregaron 124 tarjetas. Encuestamos 68 pacientes (50,8%): el 48% tenian enfermedad de Crohn, el 50% colitis ulcerosa, y el 2% otras. Los resultados indican que de 1-2 pacientes de 10 al ano tuvieron que acudir al uso mensual de la tarjeta. La tarjeta demostro una mejoria significativa en la calidad de vida de los pacientes en brote, logrando un acceso mas rapido a los lavabos. Llama la atencion que los miembros del grupo que no utilizaron la tarjeta indican mejoria en su calidad de vida, lo cual se podria explicar por haberles proporcionado mas seguridad y reconocimiento de su enfermedad. Conclusiones La totalidad coincidio en considerar el proyecto bueno o excelente pero que no hay suficientes establecimientos adheridos, lo cual incita a una mayor promocion del proyecto.

The fabrication of whole Al-doped ZnO nanostructured electrodes is reported by a two-step technology. Magnetron sputtered Al-doped ZnO (AZO) films were investigated as seeding substrates for the electrodeposition of Al-doped ZnO nanorod arrays. The nucleation, density, morphological and structural properties of Al-doped ZnO NRAs were analyzed as a function of precursor concentration and substrate and compared to undoped ZnO NRAs. High density and good crystal quality are reported for the Al-doped ZnO NRAs grown on AZO films from low precursor concentration.

Electroless Ni-Mo-P coatings were deposited onto ceramic tiles in order to be employed as electrodes for the electrodeposition of ZnO and Cu2O heterojunction layers. Varying conditions, such as duration, annealing of the electroless coating and applied potential, and duration for ZnO electrodeposition were studied in order to optimize the properties of the ZnO/Cu2O heterojunctions toward improved photoelectrical performance. The coatings were evaluated in terms of morphology, crystalline structure, and by electrochemical and photoelectrical means. The obtained results indicated that a prolonged annealing treatment at low temperature is beneficial to improve the roughness and electrical conductivity of the Ni-Mo-P coating to further enhance the electrodeposition of ZnO. The morphology analysis revealed continuous and homogeneous Ni-Mo-P coatings. The formation of cube-like Cu2O crystals with larger grain size was induced by increasing the deposition duration of ZnO. The properties of ZnO layer are much improved when a higher cathodic potential is applied (&minus, 0.8 V) for 1 h, resulting in optimum photoelectric parameters as 1.44 mA&middot, cm&minus, 2 for the JSC and 760.23 &micro, V for the VOC value, respectively, for the corresponding heterojunction solar cell.

Background Anti-TNF and thiopurines are the only drugs that demonstrated efficacy in preventing postoperative recurrence (POR) in Crohn’s disease (CD). However, in some cases these drugs are contraindicated or have previously failed. Recently, ustekinumab was licensed for CD but no data on its efficacy in the prevention of POR is still available. Methods All CD patients in whom ustekinumab was prescribed for primary prevention of POR within the first 3 months after ileocecal or ileocolonic resection with anastomosis were identified from the ENEIDA registry (a prospectively maintained database of the Spanish Working Group in IBD –GETECCU-). We evaluated the rates of endoscopic, clinical or surgical POR in the first 18 months. Endoscopic POR was defined by a Rutgeerts score >i1 and advanced endoscopic POR by >i2. Results Thirty patients were included; ustekinumab was started after a median time of 60 days (IIQ 31–90). Concomitant immunosuppressants were used in 17%, 27% received an additional 3-month course of metronidazole after surgery. Regarding risk factors for POR: 23% were active smokers, 62% had prior resections, 33% had penetrating CD behaviour, and 22% had a history of perianal disease. In total, 36% of them had more than one risk factor. 50% had been exposed to ustekinumab prior to the index surgery (46% within the last 6 months). The median time of follow-up on ustekinumab was 17 months (IQR 11–21). Fifty-six per cent of patients had at least one endoscopic assessment within 18 months after surgery: 58% had endoscopic POR and 23% advanced endoscopic POR. Additionally, 13% presented clinical POR at the discretion of the treating physician and none developed surgical POR. Conclusion In a small clinical practice cohort, ustekinumab showed similar efficacy as that reported with anti-TNF in the prevention of endoscopic POR. Unfortunately, the lack of early endoscopic monitoring is still frequent despite the recommendations from guidelines.

[EN] A p-Cu2O/n-ZnO heterojunction grown on fluorine-doped tin oxide (FTO) substrate is reported by a combined low-cost approach employing tape-casting of ZnO layer and subsequent electrochemical deposition of Cu2O layer. Graphene oxide (GO) nanosheets were employed as nanofiller for the ZnO matrix. Moreover, a ZnO buffer layer was inserted at the interface between the Cu2O and ZnO layers. The morphological, structural and photoelectrical characteristics of these heterojunction layers were investigated by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Raman spectroscopy and photoelectrical current-voltage measurements. The results confirmed that the morphology and structure of ZnO layer were affected by the incorporation of GO nanosheets while the presence of buffer layer influenced the growth of Cu2O layer. This work shows the addition of GO and the use of ZnO buffer layer represent a viable approach towards improving the photoelectrical properties of the Cu2O/ZnO heterojunction cell., Financial support from Escuela Politecnica Nacional, Ecuador (project number PIMI 15-09) and Secretaria de Education Superior, Ciencia, Tecnologia e Innovation (SENESCYT) and Romanian National Authority for Scientific Research and Innovation, Romania CNCS - UEFISCDI (project number PN-III-P1-1.1-TE-2016-1544) is gratefully acknowledged.

ZnO-nanostructured films were obtained by electrodeposition in the presence of varying content of graphene oxide (GO) in reduced (rGO) and non-reduced state. The hybridized ZnO nanostructures were studied by X-ray diffraction measurements, scanning electron microscopy, atomic force microscopy and Raman spectroscopy and transmittance measurements. The results showed the ZnO structure and morphology are markedly influenced by graphene state (GO/rGO) and content. The photocatalytic tests indicated the ability of electrodeposited ZnO-nanostructured films to photodegrade methylene blue depends on the morphology and structure characteristics induced by both on oxygen content and sp2 recovery of carbon network in the rGO, upon a fine tuning of the rGO content in the deposited films. The obtained results demonstrate the electrodeposition as a viable approach for tuning the properties of ZnO complex structures for improved performance in various fields of application such as photocatalysis or optoelectronics.

Green reduction of graphene oxide (GO) functionalized with 3-aminopropyltriethoxysilane and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide was performed by using ascorbic acid and sodium bisulfite. The obtained materials were characterized by thermo-gravimetric analysis, transmission electron microscopy, X-ray diffraction, UV‒Vis, Fourier transform infrared and Raman spectroscopy techniques. The results indicated a strong dependence of the materials properties such as deoxygenation degree, absorption peak shift, crystallite size and functionalization degree on the functionalization approach and reducing agent.

[EN] Large areas of reduced graphene oxide (rGO) films were obtained by electrophoretic deposition onto insulating glass substrate. ZnO nanostructures were directly grown on the rGO films by single-step electrodeposition method. The properties of ZnO nanostructures were evaluated as a function of deposition mode onto rGO electrodes with different stoichiometry. Atomic force microscopy (AFM), X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetrical analysis (TGA), transmission measurements, Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) were employed to characterize the obtained materials. Bi-pod morphology was observed for ZnO electrodeposited on rGO films by pulsed current elelctrodeposition. The obtained ZnO/rGO hybrid structures show high potential for highly transparent optoelectronic nanodevices., Financial support from Romanian Authority for Scientific Research-UEFISCDI (project no. PN-II-RU-PD-2012-3-0124) and European Commission (project no. NMP3-SL-2010-246073) is gratefully acknowledged. The authors also thank for the support given by the Microscopy Service and Institute of Chemical Technology (ITQ)-Universidad Politecnica de Valencia.

Surface studies are reported for the deposition of ZnO nanostructures by one-step electrodeposition method. The electrosynthesis was perfomed at the surface of tin doped indium oxide coated glass substrates in the absence of any buffer layer. The growth of ZnO nanostructures was investigated with the morphology of substrate and the deposition mode. Combined nucleation mode was observed for the ZnO independently of substrate. The results indicated the growth, morphology and density of the ZnO nanostructures are markedly influenced by both the substrate and the deposition conditions. It was observed the ZnO formation is defect site driven in case of galvanostatic deposition mode, while in case of potentiostatic deposition mode, it is dependent on the roughness of the substrate.

Since it was first published the conception of underwater glider by H. Stommel (1989), many designs have been proposed based on the variable buoyancy-gliding principle for application in underwater vehicles. Underwater gliders take advantage of the differential buoyancy of a body submerged in a fluid, the Archimedes principle, for converting part of this buoyancy force in surge velocity. For doing that, gliders need surfaces conveniently oriented for obtaining a resulting velocity in the desired surge direction. This hydrodynamic forward movement is obtained during the vehicle sinking and emerging paths, which is the most characteristic constraint of underwater gliders: the need of conducting a saw-tooth navigation pattern. The differential positive-negative buoyancy effect is based on a small increase of the vehicle volume. This increase is obtained by pumping some amount of liquid-fluid in external bladders, which makes the net buoyancy of the vehicle changing from negative (sinking) to positive (climb). However, bladders as buoyancy elements have limitations in the maximum allowable displacement volume and power requirements. Low value of differential buoyancy of ± (0.25 to ±0.45) provides low values of usable force limiting the dynamic capacity of the vehicle. As a result, speeds of around 0.50 m/s are claimed to be reachable by commercial gliders, although 0.15-0.30 m/s are the most frequent horizontal resultant speed obtained. This paper proposes a different concept on this buoyancy- based propulsion technique by considering the combination of compressed gas and liquid fluid. As an example of application, they are presented first results from the field conducted with the underwater glider Alba-14 HGL. The system proposed is based on a hybrid buoyancy gas/liquid device using oil and compressed air which is expected to be an interesting solution when increased speed and maneuverability may be required. Although the maximum range of the vehicle will be affected due to restrictions in the maximum capacity of compressed gas available and for the need of counting with an associated ballast- compensating system, this concept can provide additional booster ability for dealing with high environmental energetic areas in the ocean. Further works include additional field test of the Alba-14 HGL for testing extended long term operations as well as the validation of each of the individual subsystem proposed.

The management of sensor nodes on the sea floor represents an important challenge due to the high difficulties associated to the deployment and recovering of untethered instruments on the seafloor. These difficulties are not only related to the management of the instruments themselves but also related to the valuable information that can be lost. Ambient sound and interferences, maritime traffic, marine mammals behavior, oceanographic data are all among this critical information suitable to be registered. The fact of part of these information being missed, represent a void gap in the spatio-temporal identification phenomena analysis. For reducing the risk of losing information and with the aim of providing a feasible and low cost systems for recovering information from seafloor, a hybrid glider vehicle equipped with acoustic and laser optical communications is proposed. Preliminary studies as well as experimental results of optical/acoustic communications integrated in the hybrid glider Alba14 as data mule are presented.

We report on the optimisation of the growth conditions of manganite La0.7Sr0.3MnO3 (LSMO) thin films prepared by Channel Spark Ablation (CSA). CSA belongs to pulsed electron deposition methods and its energetic and deposition parameters are quite similar to those of pulsed laser deposition. The method has been already proven to provide manganite films with good magnetic properties, but the films were generally relatively rough (a few nm coarseness). Here we show that increasing the oxygen deposition pressure with respect to previously used regimes, reduces the surface roughness down to unit cell size while maintaining a robust magnetism. We analyse in detail the effect of other deposition parameters, like accelerating voltage, discharging energy, and temperature and provide on this basis a set of optimal conditions for the growth of atomically flat films. The thicknesses for which atomically flat surface was achieved is as high as about 10-20 nm, corresponding to films with room temperature magnetism. We believe such magnetic layers represent appealing and suitable electrodes for various spintronic devices., original paper, thin film optimization, 25 pages, 9 figures

Two differently sized microspheres were sintered at 1300° C and 1400° C from 2 to 8 h in stoneware, alumina, yttria and zirconia moulds. Selecting the appropriate material to be used as a mould remains a critical issue given titanium's high reactivity at elevated temperatures. Optimum mechanical properties were obtained when sintering the smallest microspheres in yttria-coated moulds. Stiffness of the samples was lower than 40% of that of the bulk solid material, which comes closer to that of human cortical bone. Open and interconnected porosity was observed in all the specimens. © 2011 Elsevier B.V. All rights reserved., The translation of this paper was funded by the Polytechnic University of Valencia and the Universitat Jaume I.

In this work ultrafine and nanocrystalline WC–Co mixtures were obtained by low energy milling in planetary ball mill. The effect of the processing conditions on the reduction and distribution of the grain sizes and the internal strains level were studied. The characterisation of the powder mixtures was performed by means of scanning and transmission electron microscopy and X-ray diffraction analysis. Observations through SEM and TEM images showed a particle size below 100 nm, after milling. The X-ray diffraction profile analysis revealed a WC phase refined to a crystallite size of 19 nm. ƒThe mixtures obtained have been consolidated and mechanical and microstructurally characterised. The results show improvements in resistant behaviour of the material consolidated from nanocrystalline powders, in spite of the grain growth experienced during the sintering. The best results were found for the material obtained by wet milling during 100 h, which presents values of hardness higher than 1800 HV.

Co/Cu-multilayer nanowires can be exploited to develop magnetoresistive sensors. One of the easiest methods for their production is filling nanoporous templates by pulsed-electrodeposition (PED) from a single bath. Multiple parameters effecting the growth of these nano-objects must be controlled to tailor their properties. In this study, the deposition efficiency of Co/Cu-multilayer nanowires produced in nanoporous-polymeric membranes is assessed, and the influence of the space confinement produced by the nanopores themselves on the continuous and pulsed-electrodeposition is evaluated. The growth dependence on some of the most significant process parameters has been investigated. It is shown here that, for each species, when depositing Co and Cu separately, a decrease of current efficiency is observed when the charge density is increased and the pore diameter is reduced; on the contrary, in the Co/Cu-PED, changing the degree of polarization for each deposition step of the different metals results in a sensible reduction of this effect.

Porous titanium specimens have been produced by means of the space holder method. Titanium grade 3 (TiCP3) has been used as material and ammonium bicarbonate as spacer. Process parameters (compaction pressure, metal grain size range and spacer volume) influence on porosity morphology and distribution and bending strength has been analysed. The results denote an important loss of strength when comparing samples sintered without and with spacer. On the other hand, a higher bending strength was observed in the porous samples with a smaller size of ammonium bicarbonate particles. Finally, the evolution of bending strength with the compaction pressure depends on the spacer volume, having a direct dependency for reduced amounts and inverse for higher contents.