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Orbital vascular anomalies (OVAs) are a heterogeneous group of disorders frequently found in the orbital cone, the periorbital region, or within the orbit itself. OVAs are divided into tumors and malformations. The most frequent clinical presentation is exophthalmos, associated or not with an alteration of the visual axis. They may also cause acute complications, being intralesional bleeding or cellulitis the most frequent, and chronic complications, such as amblyopia and long-term visual acuity impairment. The development of imaging techniques, the use of new drugs, and the implementation of innovative procedures in interventional radiology have resulted in a significant improvement in the diagnostic and therapeutic approaches to these patients, essential to an accurate diagnosis and management.Las anomalías vasculares de la órbita (AVO) son un grupo heterogéneo de patologías que pueden presentarse con frecuencia en el cono orbitario, la región periorbitaria o dentro de la órbita misma. Las AVO se dividen en tumores y malformaciones. Su presentación clínica más frecuente es el exoftalmos, asociado o no a alteración del eje visual. Además, pueden presentar complicaciones agudas, como hemorragia intralesional o celulitis entre las más frecuentes, y complicaciones crónicas, como ambliopía y afectación de la agudeza visual a largo plazo. La evolución de las técnicas de imágenes, el uso de nuevos fármacos y la utilización de innovadores procedimientos en radiología intervencionista han posibilitado obtener una mejora significativa en los procesos diagnósticos y terapéuticos de estos pacientes, permitiendo un diagnóstico y tratamiento preciso.

The authors congratulate Professor Allan Matthews with his 70th birthday and trust many fruitful and exciting years are still to come. The paper has been written in his honor as a tribute. We are eager to seize this opportunity to thank him for his stimulus provided over the years and for his international leadership in the field of processing-property relationships in surface engineering., Deposition of thin films is an appropriate methodology to enhance the performance of a material by modification of its surface, while keeping the properties of the bulk largely unaffected. However, a practical implementation becomes less straightforward when dealing with sensitive or complex substrates, for instance, those which cannot be subjected to harsh treatments, such as cleaning and etching, or extreme deposition conditions, like high temperatures, and ion impingement et cetera. This paper concentrates on deposition processing of complex substrates. In particular, it discusses the deposition of two types of protective coatings (diamond-like carbon (DLC) films against friction and wear, and TiO2 films against UV light) on three types of thermoplastic and cellular elastomers (rubber, nylon and cork). It is demonstrated that a successful protection of thermoplastic elastomers against wear with DLC films can be attained, after a thorough adaptation of the procedure to the characteristics of the specific substrate. In addition, the paper reports the very first depositions on a cellular elastomer like cork by vapor deposition methods, including Atomic Layer Deposition (ALD)., FCT -Fundação para a Ciência e a Tecnologia(IF/00671/2013)

Introduction: Dental amalgam and adhesive materials (composite resin and glass ionomer cement) are commonly used for occluso-functional and esthetic teeth rehabilitation. The objective of this study was to assess direct posterior coronal restorative materials used by 19 students’ clinicians’ classes. Material and Methods: A retrospective study was carried out to collect from students’ performed care records the different types of restorations’ data from 1994 to 2016. The choice of materials is estimated according to education levels [1st year Master (M1), 2nd year Master (M2) 1st year Doctorate (D1)]. The collected data was processed with SPSS software. Pearson chi-square test was used to compare qualitative variables and the significance threshold set at 5%. Results: From 1994 to 2016, there were 11 registers recording 19 students’ classes distributed according to education levels. In all, 6,033 posterior teeth procedures were performed on 3,134 patients. These restorations refer to 73.4% of molars and 26.6% of premolars. In 1994, the amalgam was used for 99.86% and adhesive materials for 0.14%. However, in 2016, these same materials were frequently used in 78.86% to 21.14% for the amalgam. Between the first year of Master (M1) and the last year (D1), the use of amalgam declines over the years while that of adhesive materials increases. Conclusion: It seems, in recent years, that under the influence of educational approaches centered on adhesive materials, youngest practitioners are using composite resin more for posterior restorations compared with senior practitioners. Keywords: Adhesive materials, Dental amalgam, Posterior coronal restorations, Students clinicians.

Lipoic acid (LA) is a sulfur-containing cofactor that covalently binds to a variety of cognate enzymes that are essential for redox reactions in all three domains of life. Inherited mutations in the enzymes that make LA, namely lipoyl synthase, octanoyltransferase, and amidotransferase, result in devastating human metabolic disorders. Unfortunately, because many aspects of this essential pathway are still obscure, available treatments only serve to alleviate symptoms. We envisioned that the development of an organismal model system might provide new opportunities to interrogate LA biochemistry, biology, and physiology. Here we report our investigations on three Caenorhabditis elegans orthologous proteins involved in this post-translational modification. We established that M01F1.3 is a lipoyl synthase, ZC410.7 an octanoyltransferase, and C45G3.3 an amidotransferase. Worms subjected to RNAi against M01F1.3 and ZC410.7 manifest larval arrest in the second generation. The arrest was not rescued by LA supplementation, indicating that endogenous synthesis of LA is essential for C. elegans development. Expression of the enzymes M01F1.3, ZC410.7, and C45G3.3 completely rescue bacterial or yeast mutants affected in different steps of the lipoylation pathway, indicating functional overlap. Thus, we demonstrate that, similarly to humans, C. elegans is able to synthesize LA de novo via a lipoyl-relay pathway, and suggest that this nematode could be a valuable model to dissect the role of protein mislipoylation and to develop new therapies.

Background : The amalgam, a material that has been used for more than 150 years for posterior teeth restoration, has been controversial because of the poisoning risk related to its mercury-content. Its manipulation exposes the practitioner and his staff members to chronic mercury poisoning, which causes some pathologies. It is, therefore, less often used or even abandoned in developed countries. However, in Cote d’Ivoire, it remains the material of choice for posterior restorations for its mechanical properties and relatively low cost. Aim: This study aimed to analyze mercury vapor levels measurement within dental clinics. Materials and Methods: The study involved forty-six dental clinics in the district of Abidjan using exclusively or not the amalgam. A spectrophotometer, Lumex, was used to measure mercury vapor at two levels (garbage cans and ambient air) at the opening of dental offices’ doors. Ten measurements equally spaced by ten seconds were done for each level. The data were analyzed using the SPSS and the Student test as a statistical test. Results: Very high levels of mercury vapors have been recorded in 3/4 of dental clinics using exclusively or not the amalgam compared to the WHO threshold value (999ng/m3), whatever the measured level. Conclusion: Mercury poisoning remains a reality within dental clinics in Abidjan. Keywords: Dental clinic, Mercury vapor measurement.

Lipoic acid (LA) is a sulfur-containing cofactor covalently attached to key enzymes of central metabolism in prokaryotes and eukaryotes. LA can be acquired by scavenging, mediated by a lipoate ligase, or de novo synthesized by a pathway requiring an octanoyltransferase and a lipoate synthase. A more complex pathway, referred to as “lipoyl-relay”, requires two additional proteins, GcvH, the glycine cleavage system H subunit, and an amidotransferase. This route was described so far in Bacillus subtilis and related Gram-positive bacteria, Saccharomyces cerevisiae, Homo sapiens, and Caenorhabditis elegans. Using collections of S. cerevisiae and B. subtilis mutants, defective in LA metabolism, we gathered evidence that allows us to propose for the first time that lipoyl-relay pathways are also present in parasitic protozoa. By a reverse genetic approach, we assigned octanoyltransferase and amidotransferase activity to the products of Tb927.11.9390 (TblipT) and Tb927.8.630 (TblipL) genes of Trypanosoma brucei, respectively. The B. subtilis model allowed us to identify the parasite amidotransferase as the target of lipoate analogs like 8-bromo-octanoic acid, explaining the complete loss of protein lipoylation and growth impairment caused by this compound in T. cruzi. This model could be instrumental for the screening of selective and more efficient chemotherapies against trypanosomiases., M.C.M and A.D.U. are members of the Carrera del Investigador Científico del Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Argentina. A.S. is a doctoral fellow from CONICET, A.L and D.A.L were doctoral fellows and P.V. was a career member from the same institution. This work was supported by Fondo para la Investigación Científica y Tecnológica (Grant PICT 2016-1853); Ministerio de Ciencia Tecnología e Innovación Productiva (Grant EULACH 16/T02-0161); and Consejo Nacional de Investigaciones Científicas y Técnicas (Grant P-UE-0039 2016).

This article’s focus is the creation of intergenerational game design experiences supported by phygital video games (i.e., games that feature both digital and physical elements) for children 8–12 years of age and elders 65 years and over living in Paris and Bagnolet, France. The purpose of the article is twofold: first, to give an account of our protocol activity to highlight the implementation difficulties associated with this kind of intergenerational gameplay, and second, to inspire researchers, educators, and caregivers to include innovative uses of transmedia world building and collaborative game design as tools to connect different generations and foster community participation in intergenerational programs.

Temperature is a crucial variable that every living organism, from bacteria to humans, need to sense and respond to in order to adapt and survive. In particular, pathogenic bacteria exploit host-temperature sensing as a cue for triggering virulence gene expression. Here, we have identified and characterized two integral membrane thermosensor histidine kinases (HKs) from Gram-positive pathogens that exhibit high similarity to DesK, the extensively characterized cold sensor histidine kinase from Bacillus subtilis. Through in vivo experiments, we demonstrate that SA1313 from Staphylococcus aureus and BA5598 from Bacillus anthracis, which likely control the expression of putative ATP binding cassette (ABC) transporters, are regulated by environmental temperature. We show here that these HKs can phosphorylate the non-cognate response regulator DesR, partner of DesK, both in vitro and in vivo, inducing in B. subtilis the expression of the des gene upon a cold shock. In addition, we report the characterization of another DesK homolog from B. subtilis, YvfT, also closely associated to an ABC transporter. Although YvfT phosphorylates DesR in vitro, this sensor kinase can only induce des expression in B. subtilis when overexpressed together with its cognate response regulator YvfU. This finding evidences a physiological mechanism to avoid cross talk with DesK after a temperature downshift. Finally, we present data suggesting that the HKs studied in this work appear to monitor different ranges of membrane lipid properties variations to mount adaptive responses upon cooling. Overall, our findings point out that bacteria have evolved sophisticated mechanisms to assure specificity in the response to environmental stimuli. These findings pave the way to understand thermosensing mediated by membrane proteins that could have important roles upon host invasion by bacterial pathogens.

The proposed work aims to functionalize leathers for footwear industry with antimicrobial properties based on AgTiO2 nanoparticles. The synthesis of nanoparticles was carried out by the hydrothermal method with significant advantages in terms of time, energy savings and low cost. Anatase TiO2 nanoparticles with dimensions below 10nm were obtained as observed by X-ray diffraction and transmission electron microscopy. Fourier transform infrared spectroscopy showed that the based structure of leather was not modified by the addition of the nanoparticles. The antimicrobial activity was evaluated and it was observed that Ag containing leathers gained antimicrobial activity. In addition, the nanoparticles were found to be non-cytotoxic. This achievement, by itself, should be quite appealing to the footwear industry as it could consist in a solid value-preposition given the commonness of fungal infections promoted by humidity, poor breathability and temperature that promote the expansion of the microflora of the skin., This research is sponsored by FEDER funds through theprogram COMPETE – Programa Operacional Factores de Competitividade and by the Portuguese Foundation for Science andTechnology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2013, and UID/EMS/00285/2013 and in the framework of ERA-SIINN/0004/2013 project., info:eu-repo/semantics/publishedVersion

Global properties, such as connectivity, shape constraints and boundary polarity, are useful high-level priors for image segmentation, allowing its customization for a given target object. In this work, we introduce a new method called Connected Oriented Image Foresting Transform (COIFT), which provides global optimum solutions according to a graph-cut measure, subject to the connectivity constraint in Oriented Image Foresting Transform (OIFT), ensuring the generation of connected objects, as well as allowing the simultaneous control of the boundary polarity. While the use of connectivity constraints in other frameworks, such as in the min-cut/max-flow algorithm, leads to an NP-Hard problem, COIFT conserves the low complexity of the OIFT algorithm. Experiments show that COIFT can considerably improve the segmentation of objects with thin and elongated parts, for the same number of seeds in segmentation based on markers.

Lipoate is an essential cofactor for key enzymes of oxidative and one-carbon metabolism. It is covalently attached to E2 subunits of dehydrogenase complexes and GcvH, the H subunit of the glycine cleavage system. Bacillus subtilis possess two protein lipoylation pathways: biosynthesis and scavenging. The former requires octanoylation of GcvH, insertion of sulfur atoms and amidotransfer of the lipoate to E2s, catalyzed by LipL. Lipoate scavenging is mediated by a lipoyl protein ligase (LplJ) that catalyzes a classical two-step ATP-dependent reaction. Although these pathways were thought to be redundant, a ∆lipL mutant, in which the endogenous lipoylation pathway of E2 subunits is blocked, showed growth defects in minimal media even when supplemented with lipoate and despite the presence of a functional LplJ. In this study, we demonstrate that LipL is essential to modify E2 subunits of branched chain ketoacid and pyruvate dehydrogenases during lipoate scavenging. The crucial role of LipL during lipoate utilization relies on the strict substrate specificity of LplJ, determined by charge complementarity between the ligase and the lipoylable subunits. This new lipoyl-relay required for lipoate scavenging highlights the relevance of the amidotransferase as a valid target for the design of new antimicrobial agents among Gram-positive pathogens. Fil: Rasetto, Natalí Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina Fil: Lavatelli, Antonela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina Fil: Martin, Natalia. Michigan State University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina Fil: Mansilla, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina

Two component systems, composed of a receptor histidine kinase and a cytoplasmic response regulator, regulate pivotal cellular processes in microorganisms. Here we describe a new screening procedure for the identification of amino acids that are crucial for the functioning of DesK, a prototypic thermosensor histidine kinase from Bacillus subtilis. This experimental strategy involves random mutagenesis of the membrane sensor domain of the DesK coding sequence, followed by the use of a detection procedure based on changes in the colony morphogenesis that take place during the sporulation programme of B. subtilis. This method permitted us the recovery of mutants defective in DesK temperature sensing. This screening approach could be applied to all histidine kinases of B. subtilis and also to kinases of other bacteria that are functionally expressed in this organism. Moreover, this reporter assay could be expanded to develop reporter assays for a variety of transcriptionally regulated systems. Fil: Diaz, Alejandra Raquel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiárida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiárida; Argentina Fil: Porrini, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina Fil: de Mendoza, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina Fil: Mansilla, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Biología Molecular y Celular de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Bioquímicas y Farmacéuticas. Instituto de Biología Molecular y Celular de Rosario; Argentina

Lipoate is an essential cofactor for key enzymes of oxidative and one-carbon metabolism. It is covalently attached to E2 subunits of dehydrogenase (DH) complexes and the GcvH subunit of the glycine cleavage system.Bacillus subtilispossess two protein lipoylation pathways: biosynthesis and scavenging. The former requires octanoylation of GcvH, amidotransfer of the octanoate to E2s, and insertion of sulfur atoms. Lipoate scavenging is mediated by a lipoate ligase (LplJ), that catalizes a classical two-step ATP-dependent reaction. Although these pathways were thought to be redundant, a ΔlipLmutant, unable to transfer the octanoyl group from GcvH to the E2s during lipoate synthesis, showed growth defects in minimal media even when supplemented with this cofactor, despite the presence of a functional LplJ. In this study we demonstrated that LipL is essential to modify E2 subunits of branched chain ketoacid and pyruvate DH during lipoate scavenging. LipL must be functional and it is not forming a complex with LplJ, which suggests that these enzymes might be acting sequentially. We also show that the E2 subunit of oxoglutarate DH is a good donor for LipL amidotransfer reaction. The essential role of LipL during lipoate utilization relies on the strict substrate specificity of LplJ, determined by charge complementarity between the ligase and the lipoylable subunits. LplJ does not recognize E2 subunits without a negatively charged residue in key positions of the target protein, and thus LipL is required to transfer the lipoate to them. This model of lipoate scavenging seems widespread among Gram-positive bacteria.

RESUMEN Las infecciones víricas por Epstein-Barr (EBV) y Adenovirus (AdV) representan una causa significativa de morbi-mortalidad en pacientes sometidos a un trasplante alogénico de progenitores hematopoyéticos debido al uso de tratamientos inmunomielosupresores y al prolongado periodo de inmunodeficiencia que generan. Hasta el momento, se ha demostrado el papel protector post-trasplante de los linfocitos T CD8+ (CTLs) específicos de EBV y AdV. Sin embargo, otros factores son cada vez más importantes en la regulación de la reconstitución y actividad de CTLs específicos para estos virus, como las diferentes subpoblaciones celulares (linfocitos T CD4+, linfocitos T reguladores, células dendríticas, células Natural Killer, etc.), mecanismos moleculares de inmunoregulación y los fármacos administrados al paciente como profilaxis para una posible enfermedad de injerto contra huésped. El objetivo de esta revisión es analizar la importancia de la monitorización de la respuesta celular específica funcional frente a EBV y AdV en el manejo de los pacientes post-trasplante. ABSTRACT Epstein-Barr (EBV) and Adenovirus (AdV) viral infections represent a significant cause of morbi-mortality in allogeneic hematopoietic stem cell transplantation recipients due to the use of immunomyelosuppressive treatments and the prolonged period of immunodeficiency that they generate. To date, the post-transplant protective role of EBV and AdV specific CD8+ T lymphocytes (CTLs) has been demonstrated. However, other factors are increasingly important in regulating the reconstitution and activity of CTLs specific to these viruses such as different cell subpopulations (CD4 + T lymphocytes, regulatory T lymphocytes, dendritic cells, Natural Killer cells, etc.), molecular mechanisms of immunoregulation and the drugs administered to the patient as prophylaxis for a possible graft-versus-host disease. The aim of this review is to analyze the importance of monitoring the functional EBV and AdV-specific cellular response in the management of post-transplant recipients.

The study of polycrystalline CeO2 + xSm2O3 (x = 0, 10.9–15.9 mol %) thin films deposited by Electron Beam Physical Vapour Deposition (EB-PVD) and Ionic Beam Assisted Deposition (IBAD) techniques on the Si substrate was devoted to the influence of deposition conditions used, namely composition x, deposition temperature T dep and Ar+ ion bombardment as well as the structure and (micro)structure on the (micro)hardness H using the differential hardness, Hdif, as a parameter. The investigations were made using, as in our recent papers, the depth sensing indentation (DSI) technique. The study was focused on the depth dependence of the film/substrate system response on the indentation response from the surface of films up to the film/substrate interface. This study has shown that the critical indentation depth, where the influence of substrate is negligible, can be observed for some CeO2 films doped with Sm2O3 as well as for undoped CeO2 films, both deposited at Tdep = 200°C without IBAD as well as using IBAD. Besides it, a wavy character of differential curve due to the inhomogeneities of films was observed with good reproducibility at some films. It was proven, that the method of differential hardness measurement is applicable for the determination of critical indentation depth as well as for the study of microstructure response of thin films from the film surface up to the film/substrate interface. Results of this study are described and discussed.

This paper concentrates on an extension of a rather new methodology to determine local residual gradients at an enhanced lateral resolution using the so-called slit milling technique. The method is based on stress relaxation by making a slit using a focused ion beam and the displacements are measured through digital image correlation so as to calculate the residual stress. Our novel approach consists of a multiple fitting procedure along the length of the slit instead of the commonly applied averaging method. The applicability of our approach is demonstrated when stress gradients exist. In accordance to the Saint-Venant principle in linear elasticity, longer slits are better than shorter slits because of end effects. The proof-of-principle is supported by measurements on steel under controlled bending and by finite element modeling.

In this work Ta1 − xOx coatings were deposited by DC magnetron sputtering in an Ar + O2 atmosphere. The influence of the oxygen partial pressure on the morphology (SEM), structure (XRD), chemical bonding (XPS), thermal oxidation and optical response (FTIR and spectroscopic ellipsometry) of Ta-based films was study. Cross-section morphology revealed that the increase of oxygen content in the coatings change the columnar morphology to featureless. Likewise, structural results showed that the small increase of oxygen amount leads to a change from Ta stable phase (α-Ta: bcc) to a mixture of phases achieving oxide phases with large amounts of oxygen. Whereas at room temperature the oxide coatings mainly revealed an amorphous character, at 700 °C the coating reached the crystallization Ta2O5 orthorhombic phase, which is promoted by the temperature. Further, although not observed in XRD, for the coatings deposited close to the reactive mode threshold IR showed absorption bands corresponding to amorphous phase containing some crystals embedded on it, while for the coatings deposited in the poisoned regime the IR suggests a marked amorphous nature. Refractive index varied between 2.09 and 2.27 at 0.65 μm, within the range reported for Ta2O5 thin films. The changes in refractive index are correlated with the different crystallinity of the coatings, which is corroborated with the IR results., This research is sponsored by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/ FIS/04650/2013 and with a PhD fellowship SFRH/BD/98199/2013. The authors also thank the financial support by IAPMEI funds through QREN – Implantes dentários inteligentes – SMARTDENT, Projeto Vale Inovação n.° 2012/24005, the project “Efeito sobre a saúde humana do tratamento de couros para a indústria do calçado com nanomateriais de Ag-TiO2 - ERA-SIINN/0004/2013” financed by OE of FCT, the PAULIF program “Programa Ações Universitárias Integradas Luso-Francesas – PAUILF – 2014” with the project “Development of bioactive surfaces for bone ingrowth on dental implant”, action integrated number TC 08/14 and MCTES – SPRH/BSAB/128423/2017 project., info:eu-repo/semantics/publishedVersion

This paper presents a statistical method to analyze instabilities that can be introduced during imaging in scanning electron microscopy (SEM). The method is based on the correlation of digital images and it can be used at different length scales. It consists of the evaluation of three different approaches with four parameters in total. The methodology is exemplified with a specific case of internal stress measurements where ion milling and SEM imaging are combined with digital image correlation. It is concluded that before these measurements it is important to test the SEM column to ensure the minimization and randomization of the imaging instabilities. The method has been applied onto three different field emission gun SEMs (Philips XL30, Tescan Lyra, FEI Helios 650) that represent three successive generations of SEMs. Important to note that the imaging instability can be quantified and its source can be identified.

Bacillus subtilis responds to a sudden decrease in temperature by transiently inducing the expression of the des gene encoding for a lipid desaturase, D5-Des, which introduces a double bond into the acyl chain of preexisting membrane phospholipids. This D5-Des-mediated membrane remodeling is controlled by the cold-sensor DesK. After cooling, DesK activates the response regulator DesR, which induces transcription of des. We show that inhibition of fatty acid synthesis by the addition of cerulenin, a potent and specific inhibitor of the type II fatty acid synthase, results in increased levels of short-chain fatty acids (FA) in membrane phospholipids that lead to inhibition of the transmembraneinput thermal control of DesK. Furthermore, reduction of phospholipid synthesis by conditional inactivation of the PlsC acyltransferase causes significantly elevated incorporation of long-chain FA and constitutive upregulation of the des gene. Thus, we provide in vivo evidence that the thickness of the hydrophobic core of the lipid bilayer serves as one of the stimulus sensed by the membrane spanning region of DesK. Fil: Porrini, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario, Facultad de Ciencias Bioqu ímicas y Farmacéuticas, Departamento de Microbiolog ía; Argentina Fil: Cybulski, Larisa Estefania. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario, Facultad de Ciencias Bioqu ímicas y Farmacéuticas, Departamento de Microbiolog ía; Argentina Fil: Altabe, Silvia Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario, Facultad de Ciencias Bioqu ímicas y Farmacéuticas, Departamento de Microbiolog ía; Argentina Fil: Mansilla, Maria Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario, Facultad de Ciencias Bioqu ímicas y Farmacéuticas, Departamento de Microbiolog ía; Argentina Fil: de Mendoza, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Rosario. Instituto de Biología Molecular y Celular de Rosario; Argentina. Universidad Nacional de Rosario, Facultad de Ciencias Bioqu ímicas y Farmacéuticas, Departamento de Microbiolog ía; Argentina

The study of polycrystalline CeO2 + xSm2O3 (x = 0, 10.9–15.9 mol %) thin films deposited by Electron Beam Physical Vapour Deposition (EB-PVD) and Ionic Beam Assisted Deposition (IBAD) techniques on the Si substrate was devoted to the influence of deposition conditions used, namely composition x, deposition temperature T dep and Ar+ ion bombardment, on the (micro)hardness, H pl and elastic modulus, Y with respect to the film structure and microstructure. These mechanical characteristics were investigated by the depth sensing indentation (DSI) technique as the functions of relative indentation depth h rel = h max/t and the values obtained were compared with those obtained by the classical Vickers technique. Results of this study are described and discussed.

Highly pure metallic structures can be deposited by electron beam induced deposition and they have many important applications in different fields. The organo-metallic precursor is decomposed and deposited under the electron beam, and typically it is purified with post-irradiation in presence of O2. However, this approach limits the purification to the surface of the deposit. Therefore, 'in situ' purification during deposition using simultaneous flows of both O2 and precursor in parallel with two gas injector needles has been tested and verified. To simplify the practical arrangements, a special concentric nozzle has been designed allowing deposition and purification performed together in a single step. With this new device metallic structures with high purity can be obtained more easily, while there is no limit on the height of the structures within a practical time frame. In this work, we summarize the first results obtained for 'in situ' Au purification using this concentric nozzle, which is described in more detail, including flow simulations. The operational parameter space is explored in order to optimize the shape as well as the purity of the deposits, which are evaluated through scanning electron microscope and energy dispersive x-ray spectroscopy measurements, respectively. The observed variations are interpreted in relation to other variables, such as the deposition yield. The resistivity of purified lines is also measured, and the influence of additional post treatments as a last purification step is studied., EMPA is acknowledged for providing the original code for the GIS simulator model, which was extended by Stan de Muijnck (TU Delft) with the new geometry. Pleun Dona (FEI) is acknowledged for helping in the design of the concentric nozzle and in getting a working prototype. Patricia Peinado is also acknowledged for help on experimental activities. This work was supported by NanoNextNL program, a Dutch national research and technology program for micro- and nano-technology.

Because of the importance of diatoms and the lack of information about their third dimension, a new method for the 3D reconstruction is explored, based on digital image correlation of several scanning electron microscope images. The accuracy of the method to reconstruct both centric and pennate (symmetrical and asymmetrical) diatoms was shown, independently of valve size and shape, and considering not only the general frustule morphology but also the intricate ornamentation. Several measurements were obtained, such as of the surface and projected areas and the valve volume. These results were validated by focused ion beam transverse cross section of one valve, and the quantitative results were compared with geometric models commonly applied. Furthermore, direct volume calculations based on 3D reconstructions have several advantages, such as it has higher taxonomic accuracy than the methods based on light microscopy; it solves the problems of the light halos; it allows the precise measurement of all linear dimensions, including the often neglected third dimension; natural samples can be measured directly; and it provides an exact estimate of cell volume, independently of its shape or alterations due to life cycle stage. This approach provides therefore a simple way to measure the morphological features of diatoms, even at a nanoscale, and can be applied to other microorganisms commonly illustrated by means of scanning electron microscopy.

In secondary ion mass spectrometry, high depth resolution for the characterization of ultra-shallow junctions can only be obtained when making use of low-energy primary ion bombardment. However, such analysis conditions often lead to roughness formation at the crater bottoms. In this paper, roughness formation has been studied on silicon for Cs+ bombardment on the Cameca (Gennevilliers, France)SC-Ultra instrument. Impact energies have been changed from 250 eV up to 5 keV working in positive secondary ion polarity. The surface morphology has been characterized by atomic force microscopy. Surface roughening appeared at low primary ion fluence and continued growing at higher fluences. Ripples formed perpendicular to the plane containing the beam and the normal to the surface. Their wavelength and correlation length have been studied as a function of the experimental conditions. Both parameters increase with increasing ion fluence, and higher values of ion energy promoted more ordered rippled structures and lower values of roughness. Copyright © 2012 John Wiley & Sons, Ltd.

Storing Matter is a new technique developed to avoid the matrix effect appearing during secondary ion mass spectrometry (SIMS) analysis by decoupling the sputtering step of the sample to be analyzed from the subsequent analysis step by SIMS. Prior to the analysis, the emitted matter is deposited at a sub-monolayer level on a well known collector, whose oxidation state may influence the secondary ion yields of the deposit. The aim of this work is to study the influence of the oxidation of a Si collector on the secondary ion yields of In and Au deposits analyzed in positive and negative modes, respectively. We have observed in our study that extreme variations of the level of oxidation alter the ion yield, although the oxidation generated on a Si-0 collector under vacuum is not enough to induce relevant changes. (C) 2012 Elsevier B. V. All rights reserved.

The storing matter technique is a new analytical technique which has been developed to avoid the matrix effect observed in secondary ion mass spectrometry. This new technique gives the possibility of decoupling the sputtering step from the subsequent analysis step by SIMS. During the sputtering the emitted matter is deposited on a well known collector. Since the matter sputtered from different samples or layers is deposited on the same virgin collector, it makes the quantification easier and more accurate. In order to study the efficacy of this technique, storing matter depth profiles are compared with traditional SIMS depth profiles for a boron implanted SiO2/Si. A boron-doped sample was used as a reference. The traditional SIMS depth profile for the implanted sample shows two peaks caused by the matrix effect, an initial sharp peak due to native SiO2 at the surface, and an additional broad peak due to the high concentration of B-11 at 400 nm below the surface. In contrast, the reconstructed depth profile by storing matter shows that those matrix effects can be eliminated, therefore avoiding problems of quantification. (C) 2012 Elsevier B.V. All rights reserved.

Nowadays, the use of low energy ion bombardment in secondary ion mass spectrometry (SIMS) is a mandatory step to obtain high depth resolution for the characterization of ultra shallow junctions. However, increment of roughness during ion bombardment leads to the degradation of depth resolution. The evolution of surface roughening and ripple formation on silicon at ambient temperature under 1 keV Cs + ion bombardment with and without sample rotation has been studied by means of atomic force microscopy. Ripple formation with a perpendicular orientation with respect to the Cs + beam direction has been detected, and their wavelength and correlation length have been monitored as a function of the experimental conditions. Roughness and wavelength increased with increasing ion fluence, while variations of ion flux showed little effect. The effect of sample rotation during ion bombardment led to a critical reduction of the surface roughness and disappearance of ripples.

In the companion paper (Martin et al., 2011) we reported that Bacillus subtilis requires three proteins for lipoic acid metabolism, all of which are members of the lipoate protein ligase family. Two of the proteins, LipM and LplJ, have been shown to be an octanoyltransferase and a lipoate:protein ligase, respectively. The third protein, LipL, is essential for lipoic acid synthesis, but had no detectable octanoyltransferase or ligase activity either in vitro or in vivo. We report that LipM specifically modifies the glycine cleavage system protein, GcvH, and therefore another mechanism must exist for modification of other lipoic acid requiring enzymes (e.g., pyruvate dehydrogenase). We show that this function is provided by LipL which catalyzes the amidotransfer (transamidation) of the octanoyl moiety from octanoyl-GcvH to the E2 subunit of pyruvate dehydrogenase. LipL activity was demonstrated in vitro with purified components and proceeds via a thioester-linked acyl-enzyme intermediate. As predicted, ΔgcvH strains are lipoate auxotrophs. LipL represents a new enzyme activity. It is a GcvH:[lipoyl domain] amidotransferase that probably employs a Cys-Lys catalytic dyad. Although the active site cysteine residues of LipL and LipB are located in different positions within the polypeptide chains, alignment of their structures show these residues occupy similar positions. Thus, these two homologous enzymes have convergent architectures.

Introduction: The choice of restorative materials has for a long time been determined by the tooth position. Thus, premolar restoration depended on the practitioner's clinical assessment and practical experience in regard to the material to be handled. Aim: The objective of this study was to assess, in the students' practice, the change in the choice of materials used for premolars restoration. Materials and Methods: This was a retrospective study based on the available care records in the department of conservative dentistry and endodontics of a dental school. Variables analyzed included the year of restoration, the type of material, the premolar position in the arch, and the coronal restoration site (occlusal, proximal, and cervical). Data collected were processed with the SPSS software version 22 (SPSS Inc., Chicago, IL, USA; 2013). The statistical significance threshold was set at 5% for Pearson's Chi-square test. Results: Between 1994 and 2017, 1738 restored premolars were identified. Over the years, amalgam restorations declined from 99.2% in 1994 to 1.3% in 2017, contrary to composite whose frequency increased from 0.6% to 88.6%. Maxillary premolars were exclusively restored with composite in 2017 when amalgam was still, somewhat, used for mandibular premolars. Conclusion: The reversal in the choice of materials in favor of composites reflects the global trend. This seems to be related to the current awareness of the prohibition, among others, of medical devices containing mercury.

Storing Matter is a new analytical technique for organic and inorganic materials, which has been developed to avoid the SIMS matrix effect while keeping or even improving the excellent sensitivity of SIMS. The technique consists in separating the sputtering of the sample to be analyzed from the subsequent analysis step by SIMS. During the sputtering process the molecules and atoms emitted under ion bombardment of the sample are deposited in a monolayer regime on a well known collector surface. Enhanced secondary ion emission can be obtained during the subsequent SIMS analysis as the chemical nature of the surface can be selected with respect to the element to be analyzed and the different SIMS analysis modes (M + , M-, cationization for organic information, etc.). Depositing the matter emitted from different layers or from different samples on the same collector surface makes Storing Matter a powerful tool not only to circumvent the SIMS matrix effect, but also to improve the excellent sensitivity of the SIMS technique. A prototype instrument has been developed to perform the different steps of the Storing Matter technique under optimized conditions. The aim of this work is to present the analytical performance obtained with the Storing Matter technique for six collector materials (Ta, Ag, Al, Au, Ni and Pt) for two different elements and analysis modes (In in positive mode and Au in negative mode).