The use of internal audits as a tool to analyze skills and competences

[EN] The degrees of the faculty of Chemistry of the University of Barcelona have implemented a quality management system (QMS) (Real Decreto 1393/2007; Real Decreto 861/2010). One of the common subjects taught in formative period of the students is Quality and Prevention. The competences that the students must acquire are knowing the QMS and the basis of certification and accreditation. They must also have skills to plan and propose actions to ensure quality and to prepare documentation of a quality management system, among others. The aim of the work is the execution of internal audits carried out by students to analyze the degree of skills and competences obtained by the auditors throughout the course Quality and Prevention.Fernandez, J.; Cruells, M.; Escaja, N.; Garrido, JA.; Giménez, J.; Llauradó, M.; Roca, A.... (2016). The use of internal audits as a tool to analyze skills and competences. En 2nd. International conference on higher education advances (HEAD'16). Editorial Universitat Politècnica de València. 196-202. https://doi.org/10.4995/HEAD16.2015.2647OCS19620

Comparison of Vacuum Treatments and Traditional Cooking Using Instrumental and Sensory Analysis

The purpose of this work was to compare carrots with similar firmness cooked by traditional cooking and two vacuum treatments: sous-vide (SV) and cook-vide (CV). As a first step, consumers determined the preferred level of firmness for carrots cooked by traditional cooking (boiling). This level corresponded to instrumental firmness of 2.8 N in phloem tissue and 4.1 N in xylem tissue. Response surface methodology (RSM) established the pairing conditions of time (22 to 78 min) and temperature (78 to 92 °C) to study the effect of both factors on the firmness of carrots with sous-vide and cook-vide treatments. In both treatments, the instrumental firmness of phloem and xylem samples was measured and modeled. No significant differences were found in firmness values between phloem and xylem tissue of samples cooked by vacuum treatments (CVand SV). For CV treatment, firmness decreased linearly with time and temperature, while for SV treatment it followed a second-order model. Based on the model, conditions of time and temperature to achieve the preferred firmness (2.8 N) were selected for both treatments. Finally, consumers compared the sensory properties of carrots cooked by traditional cooking, sous-vide, and cook-vide with paired comparison tests evaluating three pairs of samples. Carrots cooked by cook-vide were considered less tasty than sous-vide and traditional cooking carrots. Carrots using traditional cooking were firmer than those obtained with SV and CV treatments. Carrots cooked by traditional and sous-vide treatments were preferred to cook-vide ones for the taste.Consuelo Iborra- Bernad has received research grant from the Generalitat Valenciana. Amparo Tarrega was financially supported by the Juan de la Cierva program. Purificacion Garcia-Segovia declares that she has no conflict of interest. Javier Martinez-Monzo declares that he has no conflict of interest. This article does not contain any studies with human or animal subjects.Iborra Bernad, MDC.; Tarrega, A.; García Segovia, P.; Martínez Monzó, J. (2014). Comparison of Vacuum Treatments and Traditional Cooking Using Instrumental and Sensory Analysis. Food Analytical Methods. 7(2):400-408. doi:10.1007/s12161-013-9638-0S40040872Alasalvar C, Grigor J, Quantick P (1999) Method for the static headspace analysis of carrot volatiles. Food Chem 65:391Arcia P, Costell E, Tárrega A (2010) Thickness suitability of prebiotic dairy desserts: Relationship with rheological properties. Food Res Int 43:2409Baldwin DE (2012) Sous vide cooking: A review. Int J Gastronomy Food Sci 1:15Bourne MC (2002) Food texture and viscosity: concept and measurement. Academic, San DiegoDauchet L, Amouyel P, Hercberg S, Dallongeville J (2006) Fruit and vegetable consumption and risk of coronary heart disease: a meta-analysis of cohort studies. J Nutr 136:2588Fan L, Zhang M, Xiao G, Sun J, Tao Q (2005) The optimization of vacuum frying to dehydrate carrot chips. Int J Food Sci Tech 40:911Furfaro M, Marigheto N, Moates G, Cross K, Parker M, Waldron K, Hills B (2009) Multidimensional NMR cross-correlation relaxation study of carrot phloem and xylem. Part II: Thermal and high-pressure processing. Appl Magn Reson 35:537Gacula JRM, Rutenbeck S, Pollack L, Resurreccion AVA, Moskowitz HR (2007) The Just‐About‐Right intensity scale: functional analyses and relation to hedonics. J Sens Stud 22:194Gan HE, Karim R, Muhammad SKS, Bakar JA, Hashim DM, Rahman RA (2007) Optimization of the basic formulation of a traditional baked cassava cake using response surface methodology. LWT- Food Sci Technol 40:611García-Segovia P, Andrés-Bello A, Martínez-Monzó J (2008) Textural properties of potatoes (Solanum tuberosum L., cv. Monalisa) as affected by different cooking processes. J Food Eng 88:28García-Segovia P, Barreto-Palacios V, Iborra-Bernad C, Andrés-Bello A, González-Carrascosa R, Bretón J, Martínez-Monzó J (2012) Improvement of a culinary recipe by applying sensory analysis: Design of the New Tarte Tatin. Int J Gastronomy Food Sci 1:54Greve LC, Mcardle RN, Gohlke JR, Labavitch JM (1994a) Impact of heating on carrot firmness: changes in cell wall components. J Agric Food Chem 42:2900Greve LC, Shackel KA, Ahmadi H, Mcardle RN, Gohlke JR, Labavitch JM (1994b) Impact of heating on carrot firmness: contribution of cellular turgor. J Agric Food Chem 42:2896Hudson BT (1993) Industrial cuisine. Cornell Hotel Restaur Adm Q 34:73Hui YH, Chen F, Nollet LML et al (2010) Handbook of fruit and vegetable flavors. Wiley, HonokenIborra-Bernad C, Philippon D, García-Segovia P, Martinez-Monzo J (2013) Optimizing the texture and color of sous-vide and cook-vide green bean pods. LWT- Food Sci Technol 51:507ISO (2005) Sensory analysis. Methodology. Paired comparison test. Standard No. 5495. International Organization for Standardization. Geneva, SwitzerlandKjeldsen F, Christensen LP, Edelenbos M (2001) Quantitative analysis of aroma compounds in carrot (Daucus carota L.) cultivars by capillary gas chromatography using large-volume injection technique. J Agric Food Chem 49:4342Kuehl RO (2000) Design of experiments: statistical principles of research design and analysis. Duxbury, New YorkLeskova E (2006) Vitamin losses: retention during heat treatment and continual changes expressed by mathematical models. J Food Compos Anal 19:252Martínez-Hernández GB, Artés-Hernández F, Colares-Souza F, Gómez PA, García-Gómez P, Artés F (2013) Innovative cooking techniques for improving the overall quality of a Kailan-hybrid broccoli. Food Bioprocess Tech 1:1. doi: 10.1007/S11947-012-0871-0Mckenna BM, Kilcast D (2004) Texture in food: solid foods. WoodheadMente A, De Koning L, Shannon HS, Anand SS (2009) A systematic review of the evidence supporting a causal link between dietary factors and coronary heart disease. Arch Intern Med 169(659)Montgomery DC, Runger GC (2010) Applied statistics and probability for engineers. Wiley, United States of AmericaMyers RH, Montgomery DC (2002) Response surface methodology: process and product optimization using designed experiments. Wiley, New YorkRiboli E, Norat T (2003) Epidemiologic evidence of the protective effect of fruit and vegetables on cancer risk. Am J Clin Nutr 78:559sRinaldi M, Dall'asta C, Meli F, Morini E, Pellegrini N, Gatti M, Chiavaro E (2012) Physicochemical and Microbiological Quality of Sous-Vide-Processed Carrots and Brussels Sprouts. Food Bioprocess Tech 1Sanchez H, Osella C, De La Torre M (2004) Use of response surface methodology to optimize glutenfree bread fortified with soy flour and dry milk. Food Sci Technol Int 10:5Schellekens M (1996) New research issues in sous-vide cooking. Trends Food Sci Technol 7:256Van Buggenhout S, Sila DN, Duvetter T, Van Loey A, Hendrickx M (2009) Pectins 58 in processed fruits. Compr Rev Food Sci F 8:105Villegas B, Tárrega A, Carbonell I, Costell E (2010) Optimising acceptability o 39 f new prebiotic low-fat milk beverages. Food Qual Prefer 21:23

Properties of Graphene: A Theoretical Perspective

In this review, we provide an in-depth description of the physics of monolayer and bilayer graphene from a theorist's perspective. We discuss the physical properties of graphene in an external magnetic field, reflecting the chiral nature of the quasiparticles near the Dirac point with a Landau level at zero energy. We address the unique integer quantum Hall effects, the role of electron correlations, and the recent observation of the fractional quantum Hall effect in the monolayer graphene. The quantum Hall effect in bilayer graphene is fundamentally different from that of a monolayer, reflecting the unique band structure of this system. The theory of transport in the absence of an external magnetic field is discussed in detail, along with the role of disorder studied in various theoretical models. We highlight the differences and similarities between monolayer and bilayer graphene, and focus on thermodynamic properties such as the compressibility, the plasmon spectra, the weak localization correction, quantum Hall effect, and optical properties. Confinement of electrons in graphene is nontrivial due to Klein tunneling. We review various theoretical and experimental studies of quantum confined structures made from graphene. The band structure of graphene nanoribbons and the role of the sublattice symmetry, edge geometry and the size of the nanoribbon on the electronic and magnetic properties are very active areas of research, and a detailed review of these topics is presented. Also, the effects of substrate interactions, adsorbed atoms, lattice defects and doping on the band structure of finite-sized graphene systems are discussed. We also include a brief description of graphane -- gapped material obtained from graphene by attaching hydrogen atoms to each carbon atom in the lattice.Comment: 189 pages. submitted in Advances in Physic

Identification of Hypoxia-Regulated Proteins Using MALDI-Mass Spectrometry Imaging Combined with Quantitative Proteomics

Hypoxia is present in most solid tumors and is clinically correlated with increased metastasis and poor patient survival. While studies have demonstrated the role of hypoxia and hypoxia-regulated proteins in cancer progression, no attempts have been made to identify hypoxia-regulated proteins using quantitative proteomics combined with MALDI-mass spectrometry imaging (MALDI-MSI). Here we present a comprehensive hypoxic proteome study and are the first to investigate changes in situ using tumor samples. In vitro quantitative mass spectrometry analysis of the hypoxic proteome was performed on breast cancer cells using stable isotope labeling with amino acids in cell culture (SILAC). MS analyses were performed on laser-capture microdissected samples isolated from normoxic and hypoxic regions from tumors derived from the same cells used in vitro. MALDI-MSI was used in combination to investigate hypoxia-regulated protein localization within tumor sections. Here we identified more than 100 proteins, both novel and previously reported, that were associated with hypoxia. Several proteins were localized in hypoxic regions, as identified by MALDI-MSI. Visualization and data extrapolation methods for the in vitro SILAC data were also developed, and computational mapping of MALDI-MSI data to IHC results was applied for data validation. The results and limitations of the methodologies described are discussed. 2014 American Chemical Societ

C-Terminal Extension of the Yeast Mitochondrial DNA Polymerase Determines the Balance between Synthesis and Degradation

Saccharomyces cerevisiae mitochondrial DNA polymerase (Mip1) contains a C-terminal extension (CTE) of 279 amino acid residues. The CTE is required for mitochondrial DNA maintenance in yeast but is absent in higher eukaryotes. Here we use recombinant Mip1 C-terminal deletion mutants to investigate functional importance of the CTE. We show that partial removal of the CTE in Mip1Δ216 results in strong preference for exonucleolytic degradation rather than DNA polymerization. This disbalance in exonuclease and polymerase activities is prominent at suboptimal dNTP concentrations and in the absence of correctly pairing nucleotide. Mip1Δ216 also displays reduced ability to synthesize DNA through double-stranded regions. Full removal of the CTE in Mip1Δ279 results in complete loss of Mip1 polymerase activity, however the mutant retains its exonuclease activity. These results allow us to propose that CTE functions as a part of Mip1 polymerase domain that stabilizes the substrate primer end at the polymerase active site, and is therefore required for efficient mitochondrial DNA replication in vivo

Characterization of SpPol4, a unique X-family DNA polymerase in Schizosaccharomyces pombe

As predicted by the amino acid sequence, the purified protein coded by Schizosaccharomyces pombe SPAC2F7.06c is a DNA polymerase (SpPol4) whose biochemical properties resemble those of other X family (PolX) members. Thus, this new PolX is template-dependent, polymerizes in a distributive manner, lacks a detectable 3′→5′ proofreading activity and its preferred substrates are small gaps with a 5′-phosphate group. Similarly to Polμ, SpPol4 can incorporate a ribonucleotide (rNTP) into a primer DNA. However, it is not responsible for the 1–2 rNTPs proposed to be present at the mating-type locus and those necessary for mating-type switching. Unlike Polμ, SpPol4 lacks terminal deoxynucleotidyltransferase activity and realigns the primer terminus to alternative template bases only under certain sequence contexts and, therefore, it is less error-prone than Polμ. Nonetheless, the biochemical properties of this gap-filling DNA polymerase are suitable for a possible role of SpPol4 in non-homologous end-joining. Unexpectedly based on sequence analysis, SpPol4 has deoxyribose phosphate lyase activity like Polβ and Polλ, and unlike Polμ, suggesting also a role of this enzyme in base excision repair. Therefore, SpPol4 is a unique enzyme whose enzymatic properties are hybrid of those described for mammalian Polβ, Polλ and Polμ

Misregulation of Scm3p/HJURP Causes Chromosome Instability in Saccharomyces cerevisiae and Human Cells

The kinetochore (centromeric DNA and associated proteins) is a key determinant for high fidelity chromosome transmission. Evolutionarily conserved Scm3p is an essential component of centromeric chromatin and is required for assembly and function of kinetochores in humans, fission yeast, and budding yeast. Overexpression of HJURP, the mammalian homolog of budding yeast Scm3p, has been observed in lung and breast cancers and is associated with poor prognosis; however, the physiological relevance of these observations is not well understood. We overexpressed SCM3 and HJURP in Saccharomyces cerevisiae and HJURP in human cells and defined domains within Scm3p that mediate its chromosome loss phenotype. Our results showed that the overexpression of SCM3 (GALSCM3) or HJURP (GALHJURP) caused chromosome loss in a wild-type yeast strain, and overexpression of HJURP led to mitotic defects in human cells. GALSCM3 resulted in reduced viability in kinetochore mutants, premature separation of sister chromatids, and reduction in Cse4p and histone H4 at centromeres. Overexpression of CSE4 or histone H4 suppressed chromosome loss and restored levels of Cse4p at centromeres in GALSCM3 strains. Using mutant alleles of scm3, we identified a domain in the N-terminus of Scm3p that mediates its interaction with CEN DNA and determined that the chromosome loss phenotype of GALSCM3 is due to centromeric association of Scm3p devoid of Cse4p/H4. Furthermore, we determined that similar to other systems the centromeric association of Scm3p is cell cycle regulated. Our results show that altered stoichiometry of Scm3p/HJURP, Cse4p, and histone H4 lead to defects in chromosome segregation. We conclude that stringent regulation of HJURP and SCM3 expression are critical for genome stability

Perturbation of Host Nuclear Membrane Component RanBP2 Impairs the Nuclear Import of Human Immunodeficiency Virus -1 Preintegration Complex (DNA)

HIV-1 is a RNA virus that requires an intermediate DNA phase via reverse transcription (RT) step in order to establish productive infection in the host cell. The nascent viral DNA synthesized via RT step and the preformed viral proteins are assembled into pre-integration complex (PIC) in the cell cytoplasm. To integrate the viral DNA into the host genome, the PIC must cross cell nuclear membrane through the nuclear pore complex (NPC). RanBP2, also known as Nup358, is a major component of the cytoplasmic filaments that emanates from the nuclear pore complex and has been implicated in various nucleo-cytoplasmic transport pathways including those for HIV Rev-protein. We sought to investigate the role of RanBP2 in HIV-1 replication. In our investigations, we found that RanBP2 depletion via RNAi resulted in profound inhibition of HIV-1 infection and played a pivotal role in the nuclear entry of HIV DNA. More precisely, there was a profound decline in 2-LTR DNA copies (marker for nuclear entry of HIV DNA) and an unchanged level of viral reverse transcription in RanBP2-ablated HIV-infected cells compared to RanBP3-depleted or non-specific siRNA controls. We further demonstrated that the function of Rev was unaffected in RanBP2-depleted latently HIV infected cells (reactivated). We also serendipitously found that RanBP2 depletion inhibited the global ectopic gene expression. In conclusion, RanBP2 is a host factor that is involved in the nuclear import of HIV-1 PIC (DNA), but is not critical to the nuclear export of the viral mRNAs or nucleo-cytoplasmic shuttling of Rev. RanBP2 could be a potential target for efficient inhibition of HIV

Active-site structure, binding and redox activity of the heme–thiolate enzyme CYP2D6 immobilized on coated Ag electrodes: a surface-enhanced resonance Raman scattering study

Surface-enhance resonance Raman scattering spectra of the heme–thiolate enzyme cytochrome P450 2D6 (CYP2D6) adsorbed on Ag electrodes coated with 11-mercaptoundecanoic acid (MUA) were obtained in various experimental conditions. An analysis of these spectra, and a comparison between them and the RR spectra of CYP2D6 in solution, indicated that the enzyme’s active site retained its nature of six-coordinated low-spin heme upon immobilization. Moreover, the spectral changes detected in the presence of dextromethorphan (a CYP2D6 substrate) and imidazole (an exogenous heme axial ligand) indicated that the immobilized enzyme also preserved its ability to reversibly bind a substrate and form a heme–imidazole complex. The reversibility of these processes could be easily verified by flowing alternately solutions of the various compounds and the buffer through a home-built spectroelectrochemical flow cell which contained a sample of immobilized protein, without the need to disassemble the cell between consecutive spectral data acquisitions. Despite immobilized CYP2D6 being effectively reduced by a sodium dithionite solution, electrochemical reduction via the Ag electrode was not able to completely reduce the enzyme, and led to its extensive inactivation. This behavior indicated that although the enzyme’s ability to exchange electrons is not altered by immobilization per se, MUA-coated electrodes are not suited to perform direct electrochemistry of CYP2D6