Computational Model Based on Optical Coherence Tomography (OCT) Skin Scanning to Identify and Quantify Acute Radiation Dermatitis (ARD): A Prospective Diagnostic Study. / Modelo computacional basado en la tomografía de coherencia óptica (TCO) para identificar y cuantificar la radiodermatitis aguda (RA): estudio observacional prospectivo.

BACKGROUND: Acute radiation dermatitis (ARD) is the most widely reported radiotherapy-induced adverse event. Currently, there is no objective or reliable method to measure ARD. OBJECTIVE: Our main objective was to identify and quantify the effects of radiotherapy with a computational model using optical coherence tomography (OCT) skin scanning. Secondary objectives included determining the ARD impact of different radiotherapeutic schemes and adjuvant topical therapies. METHODS: We conducted a prospective, single-center case series study in a tertiary referral center of patients with breast cancer who were eligible for whole breast radiotherapy (WBRT). RESULTS: A total of 39 women were included and distributed according to the radiotherapeutic schemes (15, 20, and 25 fractions). A computational model was designed to quantitatively analyze OCT findings. After radiotherapy, OCT scanning was more sensitive revealing vascularization changes in 84.6% of the patients (vs 69.2% of the patients with ARD by clinical examination). OCT quantified an increased vascularization at the end of WBRT (P<.05) and a decrease after 3 months (P=.032). Erythematous skin changes by OCT were more pronounced in the 25-fraction regime. CONCLUSION: An OCT computational model allowed for the identification and quantification of vascularization changes on irradiated skin, even in the absence of clinical ARD. This may allow the design of standardized protocols for ARD beyond the skin color of the patients involved.

Computational Model Based on Optical Coherence Tomography (OCT) Skin Scanning to Identify and Quantify Acute Radiation Dermatitis (ARD): A Prospective Diagnostic Study.

BACKGROUND: Acute radiation dermatitis (ARD) is the most widely reported radiotherapy-induced adverse event. Currently, there is no objective or reliable method to measure ARD. OBJECTIVE: Our main objective was to identify and quantify the effects of radiotherapy with a computational model using optical coherence tomography (OCT) skin scanning. Secondary objectives included determining the ARD impact of different radiotherapeutic schemes and adjuvant topical therapies. METHODS: We conducted a prospective, single-center case series study in a tertiary referral center of patients with breast cancer who were eligible for whole breast radiotherapy (WBRT). RESULTS: A total of 39 women were included and distributed according to the radiotherapeutic schemes (15, 20, and 25 fractions). A computational model was designed to quantitatively analyze OCT findings. After radiotherapy, OCT scanning was more sensitive revealing vascularization changes in 84.6% of the patients (vs 69.2% of the patients with ARD by clinical examination). OCT quantified an increased vascularization at the end of WBRT (P<.05) and a decrease after 3 months (P=.032). Erythematous skin changes by OCT were more pronounced in the 25-fraction regime. CONCLUSION: An OCT computational model allowed for the identification and quantification of vascularization changes on irradiated skin, even in the absence of clinical ARD. This may allow the design of standardized protocols for ARD beyond the skin color of the patients involved.

Clinical management of plant food allergy in patients sensitized to lipid transfer proteins is heterogeneous: identifying the gaps.

BACKGROUND AND OBJECTIVE: Patients sensitized to lipid transfer protein (LTP) present a wide clinical variability. The lack of practical diagnostic and therapeutic guidelines complicate their management. The aim of the study was to describe the clinical approach of Spanish allergists to this pathology using a survey designed by PICO method and subsequent Delphi approach validation. METHODS: Designed survey was answered by 224 allergists (75% women; 57.1% with >20 years of professional experience). Homogeneity regarding clinical practice on the main points of LTP allergy diagnosis was observed, except for patients with suspected NSAID hypersensitivity (44.6% frequently include LTP skin testing). Oral food challenges were not frequently performed (63.6% occasionally to never), and they were generally (75.5%) used to confirm tolerance. It was common to recommend fruit skins avoidance (77.2%) and maintaining consumption of foods to which patients are sensitised but tolerant (99.1%). RESULTS: There was heterogeneity on other dietary indications, modifications due to co-factors, or traces avoidance. Peach sublingual immunotherapy (SLIT) was considered very/quite effective by 55.9% of allergists. The majority (79.5%) consider SLIT indicated in <25% of LTP allergic patients, based on severity (95.2%), frequency of reactions (99.4%), allergy to multiple food families (97.4%), and the quality of life/nutrition impairment (91.5%). There was different practice on SLIT prescription based on co-factor involvement. CONCLUSION: These data suggest that there is a need to increase evidence to reduce the clinical practice heterogeneity in the management of LTP allergy.

Virulence Factors of the Gut Microbiome Are Associated with BMI and Metabolic Blood Parameters in Children with Obesity.

The development of metabolic diseases is linked to the gut microbiota. A cross-sectional study involving 45 children (6 to 12 years old) was conducted to investigate the relationship between gut microbiota and childhood obesity. Anthropometric and metabolic measurements, food-frequency questionnaires (FFQs), and feces samples were obtained. Using the body mass index (BMI) z-score, we categorized each participant as normal weight (NW), or overweight and obese (OWOB). We determined 2 dietary profiles: one with complex carbohydrates and proteins (pattern 1), and the other with saturated fat and simple carbohydrates (pattern 2). The microbial taxonomic diversity and metabolic capacity were determined using shotgun metagenomics. We found differences between both BMI groups diversity. Taxa contributing to this difference, included Eubacterium sp., Faecalibacterium prausnitzii, Dialister, Monoglobus pectinilyticus, Bifidobacterium pseudocatenulatum, Intestinibacter bartlettii, Bacteroides intestinalis, Bacteroides uniformis, and Methanobrevibacter smithii. Metabolic capacity differences found between NW and OWOB, included the amino acid biosynthesis pathway, the cofactor, carrier, and vitamin biosynthesis pathway, the nucleoside and nucleotide biosynthesis and degradation pathways, the carbohydrate-sugar degradation pathway, and the amine and polyamine biosynthesis pathway. We found significant associations between taxa such as Ruminococcus, Mitsuokella multacida, Klebsiella variicola, and Citrobacter spp., metabolic pathways with the anthropometric, metabolic, and dietary data. We also found the microbiome's lipooligosaccharide (LOS) category as differentially abundant between BMI groups. Metabolic variations emerge during childhood as a result of complex nutritional and microbial interactions, which should be explained in order to prevent metabolic illnesses in adolescence and maturity. IMPORTANCE The alteration of gut microbiome composition has been commonly observed in diseases involving inflammation, such as obesity and metabolic impairment. Inflammatory host response in the gut can be a consequence of dietary driven dysbiosis. This response is conducive to blooms of particular bacterial species, adequate to survive in an inflammatory environment by means of genetical capability of utilizing alternative nutrients. Understanding the genomic and metabolic contribution of microbiota to inflammation, including virulence factor prevalence and functional potential, will contribute to identifying modifiable early life exposures and preventive strategies associated with obesity risk in childhood.

Terapia Cognitivo Conductual en pacientes con trauma infantil diverso: Evidencia de reducción de síntomas. Artículo de Revisión / Cognitive Behavioral Therapy in patients with diverse childhood trauma: Evidence of symptom reduction. Review article

La presentación de un evento traumático único o sistemático en la infancia, puede afectar el curso normal del desarrollo psíquico del infante en sus etapas evolutivas si no es abordado oportuna y adecuadamente. Métodos: Se realizó una búsqueda de artículos, de los últimos 5 años, que abordasen el efecto de la Terapia Cognitivo Conductual Centrada en el Trauma (TCC-CT) en niños y adolescentes. Resultados: Las experiencias de trauma en la primera infancia son un problema real y no infrecuentes, con efecto sobre varios dominios del desarrollo y salud del infante, por ello, es de gran importancia un tratamiento oportuno basado en la evidencia. Esta terapia es un tratamiento efectivo y ampliamente utilizado para abordar el trauma infantil. Discusión: Los artículos revisados, respaldan la TCCCT como un tratamiento efectivo y ampliamente utilizado para abordar el trauma infantil, con vasta evidencia.

The presentation of a single or systematic traumatic event in childhood can affect the normal course of the infant's psychic development in its evolutionary stages if it is not approached in a timely and adequate manner. Methods. A search was carried out for articles, from the last 5 years, that addressed the effect of Trauma-Focused Cognitive Behavioral Therapy (CBT-CT) in children and adolescents. Results. The experiences of trauma in early childhood are a real problem and not infrequent, with an effect on several domains of development and health of the infant, therefore, the great importance of a timely treatment based on evidence. This therapy is an effective and widely used treatment to address childhood trauma. Discussion. The revised articles support CBT-CT as an effective and used treatment to address childhood trauma, with ample evidence.

In vitro and in silico assessment of antitumor properties and biomolecular binding studies for two new complexes based on NiII bearing k2N,S-donor ligands.

This work deals with two new molecule-based materials, namely NiII-complexes of general formulae [Ni(L1)2] (Ni1) and [Ni(L2)2] (Ni2), where L1 = trans-cinnamaldehyde-N(4)-methyl thiosemicarbazone and L2 = trans-cinnamaldehyde-N(4)-ethyl thiosemicarbazone, as potential antitumor agents. Both compounds were characterized by elemental analysis, molar conductivity and spectroscopic techniques (FTIR and NMR). Their molecular structures were obtained by single-crystal X-ray diffraction analysis. Each one crystallizes in a monoclinic space group P 21/c, also the asymmetric unit comprises of one NiII ion located on an inversion centre and one anionic ligand, which acts as a κ2N,S-donor affording a five-membered metallaring. The compounds were screened against two selected tumour cell lines (MCF-7 and A549) and non-tumour fibroblasts cell line (MRC-5) via MTT assays. In both tumour cells, all compounds exhibited higher cytotoxicity than the control drug (cisplatin). The IC50 values ranges of 3.70 - 41.37 µM and 1.06 - 14.91 µM were found for MCF-7 and A549, respectively. Importantly, all of them were less toxicity than cisplatin in MRC-5 with SI values ranged at 11.80 - 86.60. The red blood cell (RBC) assay revealed Ni2 as non-toxic due to its reduced haemolytic effect (0--9% at 1--10 µM). The DNA binding was investigated through a combination of spectrophotometric absorption and emission titrations, electrophoresis, and circular dichroism experiments. As a result, these metal complexes were not able to strongly binding to DNA (Kb values ~104 mol L--1) but suggesting groove-binding interactions. The scavenging ability of them towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical was also evaluated in this work, but no important antioxidant behaviour was detected. Further, the interaction of Ni1 and Ni2 to human serum albumin (HSA) was explored by quenching of tryptophan emission, warfarin competitive assay, and molecular docking protocols. The HSA binding analyses indicated good affinity of both complexes to Sudlow site I (Kb values ⁓103 mol L-1).

Trend of in-hospital deaths by pulmonary embolism in Ecuador. Findings from 2011-2018 national reports.

BACKGROUND: Pulmonary embolism (PE) is a potentially fatal disease related to venous thromboembolism. Information regarding this pathology in the Ecuadorian population is limited. This study aims to present the PE hospital mortality rates (HMR) in Ecuador, analyze its trend and risk factors. METHODS: An epidemiological, descriptive and cross-sectional study based on the reporting and trend analysis of pulmonary embolism HMR in the Ecuadorian population from 2011 to 2018 through the governmental database of the Ecuadorian National Statistics and Census Institute, was conducted. RESULTS: In Ecuador, PE hospital discharges (HD) varied from 358 in 2011 to 424 in 2018. More than 60% of patients were older than 60 years. Also, the frequency of PE with acute cor pulmonale increased from 3.07% in 2011 to 16.98% in 2018 (P<0.05). The HMR by 100 HD increased between 2011 (12.85/100 HD) and 2018 (17.02/100 HD) (P<0.05), with the highest rate reported in 2017 (21.52/100 HD). In the period studied, 505 in-hospital deaths were reported in patients with PE, the average age in this group was 64.3 years, 58.42% were female, and 10.89% had acute cor pulmonale (ICD-10 I26.0). Risk factors associated with PE in-hospital death were acute cor pulmonale (OR 1.63, 95% CI: 1.18 to 2.25, P<0.01) and 60 years or more (OR 1.73, 95% CI 1.40-2.15, P<0.01). CONCLUSION: A significant increase in PE HMR in Ecuador was found. Also, acute cor pulmonale and age of 60 years or more may be potential risk factors for in-hospital death in patients with PE.

Coalescence, crystallographic orientation and luminescence of ZnO nanowires grown on Si(001) by chemical vapour transport.

We analyse the morphological, structural and luminescence properties of self-assembled ZnO nanowires grown by chemical vapour transport on Si(001). The examination of nanowire ensembles by scanning electron microscopy reveals that a non-negligible fraction of nanowires merge together forming coalesced aggregates during growth. We show that the coalescence degree can be unambiguously quantified by a statistical analysis of the cross-sectional shape of the nanowires. The examination of the structural properties by x-ray diffraction evidences that the nanowires crystallize in the wurtzite phase, elongate along the c-axis, and are randomly oriented in plane. The luminescence of the ZnO nanowires, investigated by photoluminescence and cathodoluminescence spectroscopy, is characterized by two bands, the near-band-edge emission and the characteristic defect-related green luminescence of ZnO. The cross-correlation of scanning electron micrographs and monochromatic cathodoluminescence intensity maps reveals that: (i) coalescence joints act as a source of non-radiative recombination, and (ii) the luminescence of ZnO nanowires is inhomogeneously distributed at the single nanowire level. Specifically, the near-band-edge emission arises from the nanowire cores, while the defect-related green luminescence originates from the volume close to the nanowire sidewalls. Two-dimensional simulations of the optical guided modes supported by ZnO nanowires allow us to exclude waveguiding effects as the underlying reason for the luminescence inhomogeneities. We thus attribute this observation to the formation of a core-shell structure in which the shell is characterized by a high concentration of green-emitting radiative point defects as compared to the core.

Occurrence of pyrethroid resistance mutation in Cydia pomonella (Lepidoptera: Tortricidae) throughout Argentina.

Pyrethroid insecticides were intensively used against Cydia pomonella in the Río Negro and Neuquén valley, main production area of pome fruits in Argentina. Therefore, the first objective was to evaluate lambda-cyhalothrin resistance levels in C. pomonella larvae from orchards in this area that are currently under pyrethroids treatments. The second objective was to evaluate the frequency of kdr mutation in C. pomonella across Argentina. High levels of resistance to lambda-cyhalothrin (resistance ratios > 30) were determined in all the populations evaluated. The L1014F (kdr) mutation was evaluated in 355 diapausing larvae collected in 12 orchards from San Juan to Santa Cruz provinces (1690 km away from each other). The highest frequency of kdr mutation was determined in larvae from the Río Negro and Neuquén valley (0.61), followed by those from Mendoza (0.36). The kdr allele was absent or present at very low frequencies in orchards subjected to low pyrethroid pressure. The frequency of detection of kdr mutation in C. pomonella from Argentina is related to the use of pyrethroids against this pest in different areas. Target-site insensitivity is, at least, one of the mechanisms involved in resistance to lambda-cyhalothrin in codling moth from the Río Negro and Neuquén valley.

Absence of Quantum-Confined Stark Effect in GaN Quantum Disks Embedded in (Al,Ga)N Nanowires Grown by Molecular Beam Epitaxy.

Several of the key issues of planar (Al,Ga)N-based deep-ultraviolet light-emitting diodes could potentially be overcome by utilizing nanowire heterostructures, exhibiting high structural perfection, and improved light extraction. Here, we study the spontaneous emission of GaN/(Al,Ga)N nanowire ensembles grown on Si(111) by plasma-assisted molecular beam epitaxy. The nanowires contain single GaN quantum disks embedded in long (Al,Ga)N nanowire segments essential for efficient light extraction. These quantum disks are found to exhibit intense light emission at unexpectedly high energies, namely, significantly above the GaN bandgap, and almost independent of the disk thickness. An in-depth investigation of the actual structure and composition of the nanowires reveals a spontaneously formed Al gradient both along and across the nanowire, resulting in a complex core/shell structure with an Al-deficient core and an Al-rich shell with continuously varying Al content along the entire length of the (Al,Ga)N segment. This compositional change along the nanowire growth axis induces a polarization doping of the shell that results in a degenerate electron gas in the disk, thus screening the built-in electric fields. The high carrier density not only results in the unexpectedly high transition energies but also in radiative lifetimes depending only weakly on temperature, leading to a comparatively high internal quantum efficiency of the GaN quantum disks up to room temperature.

Serum complexes between C1INH and C1INH autoantibodies for the diagnosis of acquired angioedema.

Acquired angioedema due to C1-inhibitor (C1INH) deficiency (AAE) is caused by secondary C1INH deficiency leading to bradykinin-mediated angioedema episodes. AAE typically presents in adulthood and is associated with B cell lymphoproliferation. Anti-C1INH autoantibodies (antiC1INHAbs) are detectable in a subset of AAE cases and considered a hallmark of the disease. When free antiC1INHAbs and malignant tumors are not detectable, diagnosis relies on the finding of low C1INH levels and/or function, lack of family history and SERPING1 mutations, age at onset and low or undetectable C1q levels, none of which is specific for AAE. We tested the diagnostic value of a novel enzyme-linked immunosorbent assay (ELISA) for the detection of circulating complexes between C1INH and antiC1INHAbs (C1INH-antiC1INHAb) in the serum of 20 European AAE patients characterized on the basis of their complement levels and function. Free antiC1INHAbs were detected in nine of 20 patients [six of immunoglobulin (Ig)G class, two of IgM class and one simultaneously presenting IgG and IgM classes], whereas C1INH-antiC1INHAb complexes were found in 18 of 20 of the AAE cases, regardless of the presence or absence of detectable free anti-C1INHAbs. Of note, nine of 20 patients showed negative free antiC1INHabs, but positive C1INH-antiC1INHAb complexes in their first measurement. In the cohort presented, IgM-class C1INH-antiC1INHAb are specifically and strongly associated with low C1q serum levels. Detection of C1INH-antiC1-INHAbs provides an added value for AAE diagnosis, especially in those cases in whom no free anti-C1INH antibodies are detected. The link between IgM-class C1INH-antiC1INHAb complexes and C1q consumption could have further implications for the development of autoimmune manifestations in AAE.

Comprehensive analysis of the self-assembled formation of GaN nanowires on amorphous Al x O y : in situ quadrupole mass spectrometry studies.

A comprehensive description of the self-assembled formation of GaN nanowires (NWs) by plasma-assisted molecular beam epitaxy (PAMBE) on amorphous-Al x O y buffered Si is presented. The incubation time that precedes the formation of GaN NWs is analyzed as a function of the growth parameters using line-of-sight quadrupole mass spectrometry. We found that the incubation time follows an Arrhenius-type temperature dependence as well as an inverse power law with respect to the Ga flux. Our results reveal a weaker dependence of the incubation time on the Ga flux and faster nucleation on amorphous-Al x O y in comparison to conventional nitridated Si substrates. In addition, an unprecedented analysis of the dependence of the incubation time on the N flux demonstrates a stronger dependence of the incubation time on the N than on the Ga flux. Our results are summarized in growth diagrams to visualize the impact of the growth parameters on the incubation time. The diagrams can also be used to predict the incubation time for so far unexplored growth conditions. Finally, we measured the desorbing Ga flux upon the nucleation stage to determine the growth parameters that result in effective N-rich conditions as required for the self-assembled formation of GaN NWs. These original measurements were combined with the knowledge gained on the incubation time to create a growth map that illustrates the different growth regimes that can be obtained when GaN is grown on an amorphous-Al x O y buffer layer, regardless of the host substrate. Such a map provides a useful guide to induce the growth and control the morphology of GaN NW ensembles on amorphous-Al x O y . Results presented in this work allow to conclude that amorphous-Al x O y is preferred over nitridated Si as it enables shorter incubation times as well as a wider range of growth parameters to induce the self-assembled formation of GaN NWs in PAMBE.

Interfacial reactions during the molecular beam epitaxy of GaN nanowires on Ti/Al2O3.

We investigate the occurrence of interfacial reactions during the self-assembled formation of GaN nanowires on Ti/Al2O3(0001) substrates in plasma-assisted molecular beam epitaxy. The conditions typical for the synthesis of ensembles of long nanowires (>1 µm) are found to promote several chemical reactions. In particular, the high substrate temperature leads to the interdiffusion of Al and O at the Ti/Al2O3 interface resulting in the formation of Al x Ti y O1-x-y and Ti x O1-x compounds. Furthermore, O is found to incorporate into the nanowires degrading their luminescence by heavy n-type doping. At the same time, impinging Ga and N species react with the substrate giving rise to the simultaneous formation of single-crystalline TiN and Ga x Ti y O1-x-y compounds. The latter compounds tend to form hillocks at the substrate surface, on top of which nanowires elongate with large tilt angles with respect to the substrate normal. We develop here a specific process in order to mitigate the detrimental effects of these interfacial reactions, while maintaining the low areal density and absence of coalescence which is the strong asset of growing nanowires on Ti/Al2O3. We find that the combination of a thick Ti film with an intentional low temperature nitridation step preceding nanowire growth and a limited growth temperature results in ensembles of uncoalesced and well-oriented nanowires with luminescence properties comparable to those of standard GaN nanowires prepared on Si. All these properties, together with the inherent benefits of integrating semiconductors on metals, make the present materials combination a promising platform for the further development of group-III nitride nanowire-based devices.

[Hypertensive urgencies: Description of clinical characteristics, management, variables associated with re-entry and short-term prognosis]. / Urgencias hipertensivas: descripción de características clínicas, manejo, variables asociadas a reconsulta y pronóstico a corto plazo.

OBJECTIVES: To describe the characteristics of hypertensive urgencies at the emergency department, as well as the variables associated with early re-admission (<7 days) and re-admission at one month (<30 days). METHODS: We conducted a descriptive, retrospective study of all patients who were admitted to the emergency department of a third level hospital during 2013. Subsequently, a case-control analysis was performed to analyze the group of patients with readmission. RESULTS: A total of 398 hypertensive urgencies were collected (32.4% men, mean age 67.75 years), which led to an incidence of 3.28/1000 visits. Eighty point nine percent had a previous history of hypertension, and the mean Charlson Index was 2.23. Headache was the most frequent symptom (49.1%), followed by dizziness/instability (29.5%) and nausea/vomiting (17.1%). Eighty point seven percent of the patients were prescribed pharmacological treatment. The rates of cardiovascular events or mortality at one month were low (2.26% and 0.25% respectively). Despite this, 7.53% and 11.31% of patients were readmitted in under 7 days or 30 days, respectively. The variables associated with readmission in the multivariate analysis were elevated systolic blood pressure in the first determination, previous hypertension and the presence of palpitations. CONCLUSIONS: Hypertensive emergencies are high-incidence conditions in the Emergency Department. In our study, patients with a prior diagnosis of hypertension and elevated systolic blood pressure at the first determination had a higher risk of re-entry and would be candidates for closer follow-up on discharge.

Crab-meat-isolated psychrophilic spore forming bacteria inactivation by electron beam ionizing radiation.

The present work was performed to evaluate the potential of electron beam ionizing radiation for the inactivation of three psychrophilic spore forming bacteria (Bacillus mycoides, Bacillus weihenstephanensis and Psychrobacillus psychrodurans) isolated from ready-to-eat brown crab (Cancer pagurus). Inactivation curves for the three spores were performed in both types of crab meat, brown and white. Also the effect of pH and water activity (aw) on the lethal efficacy of ionizing radiation, for the three different psychrophilic spore forming bacteria, was evaluated. The effects of pH, aw and their possible interactions were assessed in citrate-phosphate buffers of different pH, ranging between 7 and 4, and aw, ranging from <0.99 to 0.80. A reduction of aw increased the spores resistance between >0.99 and 0.90, while an aw reduction from 0.90 to 0.80 had a minor impact on their resistance. In contrast to aw, the effect of pH showed a greater variability depending on the spore species. While pH did not affect the resistance of B. weihenstephanensis at any aw, B. mycoides showed slightly higher resistance at pH 5.5 at aw of 0.90 and 0.80. pH showed a significant effect on the resistance of P. psychrodurans. For the two types of crab meat, slightly differences were observed in 6D values. B. weihenstephanensis was the most resistant, requiring 7.3-7.6 kGy to inactivate 6 Log10-cycles of this spore forming bacterium, while for B. mycoides and P. psychrodurans 6.1-6.3 and 5.4-5.3 kGy respectively were necessary to reach the same inactivation level in crab meat. An agreement between spore resistance in crab meats and lab media, with similar characteristics in pH and aw, was also observed. The results obtained in this research demonstrated the potential for ionizing radiation to achieve an appropriate inactivation level of spores naturally present in brown crab with the application of doses lower than 10 kGy.

Synergistic effect of ultrasonic waves under pressure at mild temperatures (MTS) in yeast inactivation.

Ultrasonic treatments are one of the new technologies for microbial inactivation that could serve as an alternative for food preservation. However, decimal reduction times for most of microbial species generally exceed 1 min. Therefore, combined processes have been designed, based on the simultaneous application of ultrasonic waves under pressure at moderate temperatures (mano-thermo-sonication process, MTS). The aim of this study was mathematically quantify the synergism of MTS treatments on S. bayanus and different microbial groups including vegetative cells and bacterial spores and compare them. Results show that the lethal effect of MTS treatments may have both, additive (A. hydrophila, Y. enterocolitica) or synergistic effect (S. bayanus, L. monocytogenes, Salmonella spp., Bacillus spp.). The synergistic effect increases with temperature until reaching a maximum and then descending. A big synergistic effect was observed in yeasts and bacterial spores while lower synergy was observed in bacterial vegetative cells. The more heat resistant bacterial species showed higher synergistic effect of the MTS treatments.

Effect of surface roughness, chemical composition, and native oxide crystallinity on the orientation of self-assembled GaN nanowires on Ti foils.

We report on plasma-assisted molecular beam epitaxial growth of almost randomly oriented, uniformly tilted, and vertically aligned self-assembled GaN nanowires (NWs), respectively, on different types of polycrystalline Ti foils. The NW orientation with respect to the substrate normal, which is affected by an in situ treatment of the foil surface before NW growth, depends on the crystallinity of the native oxide. Direct growth on the as-received foils results in the formation of ensembles of nearly randomly oriented NWs due to the strong roughening of the surface induced by chemical reactions between the impinging elements and Ti. Surface nitridation preceding the NW growth is found to reduce this roughening by transformation of the uppermost layers into TiN and TiO x N y species. These compounds are more stable against chemical reactions and facilitate the growth of uniformly oriented GaN NW ensembles on the surface of the individual grains of the polycrystalline Ti foils. If an amorphous oxide layer is present at the foil surface, vertically oriented NWs are obtained all across the substrate because this layer blocks the transfering of the epitaxial information from the underlying grains. The control of NW orientation and the understanding behind the achievement of vertically oriented NWs obtained in this study represent an important step towards the realization of GaN NW-based bendable devices on polycrystalline metal foils.