Use of blends of bioabsorbable poly(L-lactic acid)/poly(hydroxybutyrate- co-hydroxyvalerate) as surfaces for Vero cell culture

Vero cells, a cell line established from the kidney of the African green monkey (Cercopithecus aethiops), were cultured in F-10 Ham medium supplemented with 10% fetal calf serum at 37°C on membranes of poly(L-lactic acid) (PLLA), poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and their blends in different proportions (100/0, 60/40, 50/50, 40/60, and 0/100). The present study evaluated morphology of cells grown on different polymeric substrates after 24 h of culture by scanning electron microscopy. Cell adhesion was also analyzed after 2 h of inoculation. For cell growth evaluation, the cells were maintained in culture for 48, 120, 240, and 360 h. For cytochemical study, the cells were cultured for 120 or 240 h, fixed, processed for histological analysis, and stained with Toluidine blue, pH 4.0, and Xylidine ponceau, pH 2.5. Our results showed that cell adhesion was better when 60/40 and 50/50 blends were used although cells were able to grow and proliferate on all blends tested. When using PLLA/PHBV (50/50) slightly flattened cells were observed on porous and smooth areas. PLLA/PHBV (40/60) blends presented flattened cells on smooth areas. PLLA/PHBV (0/100), which presented no pores, also supported spreading cells interconnected by thin filaments. Histological sections showed that cells grew as a confluent monolayer on different substrates. Cytochemical analysis showed basophilic cells, indicating a large amount of RNA and proteins. Hence, we detected changes in cell morphology induced by alterations in blend proportions. This suggests that the cells changed their differentiation pattern when on various PLLA/PHBV blend surfaces.

Early responses of the STAT3 pathway to platinum drugs are associated with cisplatin resistance in epithelial ovarian cancer

Cisplatin resistance remains one of the major obstacles when treating epithelial ovarian cancer. Because oxaliplatin and nedaplatin are effective against cisplatin-resistant ovarian cancer in clinical trials and signal transducer and activator of transcription 3 (STAT3) is associated with cisplatin resistance, we investigated whether overcoming cisplatin resistance by oxaliplatin and nedaplatin was associated with the STAT3 pathway in ovarian cancer. Alamar blue, clonogenic, and wound healing assays, and Western blot analysis were used to compare the effects of platinum drugs in SKOV-3 cells. At an equitoxic dose, oxaliplatin and nedaplatin exhibited similar inhibitory effects on colony-forming ability and greater inhibition on cell motility than cisplatin in ovarian cancer. Early in the time course of drug administration, cisplatin increased the expression of pSTAT3 (Tyr705), STAT3α, VEGF, survivin, and Bcl-XL, while oxaliplatin and nedaplatin exhibited the opposite effects, and upregulated pSTAT3 (Ser727) and STAT3β. The STAT3 pathway responded early to platinum drugs associated with cisplatin resistance in epithelial ovarian cancer and provided a rationale for new therapeutic strategies to reverse cisplatin resistance.

Effectiveness of cleaning and sanitizing procedures in controlling the adherence of Pseudomonas fluorescens, Salmonella Enteritidis, and Staphylococcus aureus to domestic kitchen surfaces

The effectiveness of cleaning and sanitizing procedures in controlling Staphylococcus aureus, Salmonella Enteritidis, and Pseudomonasfluorescens adhered to granite and stainless steel was evaluated. There was no significant difference (p > 0.05) in the adherence of pure cultures of these microorganisms to stainless steel. The numbers of P. fluorescens and S. Enteritidis adhered to granite were greater (p < 0.05) than the numbers of S. aureus. Additionally, the adherence of P. fluorescens was similar to the adherence of S. Enteritidis on granite surface. In a mixed culture with P. fluorescens, S aureus adhered less (p < 0.05) to stainless steel surfaces (1.31 log CFU.cm-2) than when in a pure culture (6.10 log CFU.cm-2). These results suggest that P. fluorescens inhibited the adherence of S. aureus. However, this inhibition was not observed in the adherence process for granite. There was a significant difference (p < 0.05) between the number of adhered cells before and after pre-washing for S. aureus on stainless steel and granite surfaces, and after washing with detergent for all microorganisms and surfaces. The efficiency of the cleaning plus sanitizing procedures was not significantly different (p > 0.05) between the surfaces. However, a significant difference was observed (p < 0.05) between the sanitizer solutions. Sodium hypochlorite and peracetic acid were more bactericidal (p < 0.05) than a quaternary ammonium compound. With regard to microorganisms, S. aureus was the least resistant to the sanitizers. These results show the importance of good cleaning and sanitization procedures to prevent bacterial adherence and biofilm formation.

From restrained golden age to creeping platinum age: A periodization of Latin American development in the Robinsonian tradition

ABSTRACTThis paper analyzes Joan Robinson's growth model, and then adapted in order to provide an exploratory taxonomy of Growth Eras. The Growth Eras or Ages were for Robinson a way to provide logical connections among output growth, capital accumulation, the degree of thriftiness, the real wage and illustrate a catalogue of growth possibilities. This modified taxonomy follows the spirit of Robinson's work, but it takes different theoretical approaches, which imply that some of her classifications do not fit perfectly the ones here suggested. Latin America has moved from a Golden Age in the 1950s and 1960s, to a Leaden Age in the 1980s, having two traverse periods, one in which the process of growth and industrialization accelerated in the late 1960s and early 1970s, which is here referred to as a Galloping Platinum Age, and one in which a process of deindustrialization, and reprimarization and maquilization of the productive structure took place, starting in the 1990s, which could be referred to as a Creeping Platinum Age.

Analysis of Automotive Cybersecurity - Attack surfaces and users’ privacy concerns

Modern automobiles are no longer just mechanical tools. The electronics and computing services they are shipping with are making them not less than a computer. They are massive kinetic devices with sophisticated computing power. Most of the modern vehicles are made with the added connectivity in mind which may be vulnerable to outside attack. Researchers have shown that it is possible to infiltrate into a vehicle’s internal system remotely and control the physical entities such as steering and brakes. It is quite possible to experience such attacks on a moving vehicle and unable to use the controls. These massive connected computers can be life threatening as they are related to everyday lifestyle. First part of this research studied the attack surfaces in the automotive cybersecurity domain. It also illustrated the attack methods and capabilities of the damages. Online survey has been deployed as data collection tool to learn about the consumers’ usage of such vulnerable automotive services. The second part of the research portrayed the consumers’ privacy in automotive world. It has been found that almost hundred percent of modern vehicles has the capabilities to send vehicle diagnostic data as well as user generated data to their manufacturers, and almost thirty five percent automotive companies are collecting them already. Internet privacy has been studies before in many related domain but no privacy scale were matched for automotive consumers. It created the research gap and motivation for this thesis. A study has been performed to use well established consumers privacy scale – IUIPC to match with the automotive consumers’ privacy situation. Hypotheses were developed based on the IUIPC model for internet consumers’ privacy and they were studied by the finding from the data collection methods. Based on the key findings of the research, all the hypotheses were accepted and hence it is found that automotive consumers’ privacy did follow the IUIPC model under certain conditions. It is also found that a majority of automotive consumers use the services and devices that are vulnerable and prone to cyber-attacks. It is also established that there is a market for automotive cybersecurity services and consumers are willing to pay certain fees to avail that.

崇禎曆書 。測量全義Chong zheng li shu. — Ce liang quan yi.Collection relative au calendrier, années Chong zheng : traité de la mesure des lignes, surfaces et volumes,.

Même ouvrage.Livres 3 et 5. — Comparer Cat. imp., liv. 106, f. 21 (Xin fa suan shu, 100 livres).

Palladium and platinum complexes of vitamin Bâ

Palladium and platinum complexes of pyridoxamine, pyridoxine and pyridoxal have been prepared. The structures of the complexes PtCI2PM.H20, trans-PdC12 (PN)2 and [PLH+ ]2[PtC16] 2- ,H20 have been determined by use of single crystal x-ray studies. The compounds PdC12PH, trans-PdC12 (PN) 2 , cis-PdCI2 (PN)2 and cis PdC12 (PL)2 were also studied by use of carbon-13 nmr spectroscopy. All the complexes have also been characterised by use of infrared spectral studies. In the complexes, PtCI2PM.H20 and PdC12PM, the ligand pyridoxamine is chela ted to the metal through the aminomethyl nitrogen and the phenolate oxygen atoms whereas in the complexes, trans-PdCI2 (PN)2' cis-PdCI2 (PN)2 and cis-PdC12 (PL)2 the vitamin B6 ligands are coordinated to the metal through the pyridine ring nitrogen. The compounds [PLH+ ]2[PtCI6] 2- .H20 and [PMH2] 2+ [PdCI4] 2- .H20have no direct metal-ligand bonding, In all the complexes, the metal maintains a square planar coordination except in [PLH +] 2[PtCI6] 2- ,H20 where the metal is octahedrally coordinated. PH pyridoxamine [PMH ] 2+ = diprotonated pyridoxamine 2 PN = pyridoxine PL pyridoxal PLH+ protonated pyridoxal

Probing cell surfaces of host and nonhost species of a mycoparasite, using FITC-labeled lectins

Cell surfaces of susceptible host species (Mortierella pusllla and Cboanepilora cucurbitarum ), resistant host (Pilascolomyces articulosus ), nonhost (Mortierella candelabrum ) and the mycoparasite (Piptocepilalis virginiana) were examined for sugar distribution patterns using light and fluorescent microscopy techniques. The susceptible host, resistant host and the mycoparasite species exhibited a similar sugar distribution profile; they all showed N-acetyl glucosamine and D-glucose on their cell wall surfaces. The nonhost cell wall surface showed a positive binding reaction to FITClectins specific for N-acetyl glucosamine and also for OI.-fucose, N-acetyl galactosamine and galactose. Treatment of these fungi with mild concentrations of proteinases (both commercial as well as the mycoparasiteproteinase) resulted in the revelation of additional sugars on the fungal cell walls. The susceptible host treated with proteinase expressed higher levels of N-acetyl glucosamine and D-glucose. The susceptible host also showed the presence of OI.-fucose, N-acetyl galactosamine and galactose. The proteinasetreated susceptible host cell walls also showed an increase in the levels of attachment with the mycoparasite. Treatment of the resistant host with proteinases revealed OI.-fucose in addition to N-acetyl glucosamine and D-glucose. Treatment of the nonhost cell wall with proteinase resulted in the exposure of low levels of D-glucose, in addition to sugars found on the untreated nonhost cell wall surface. The mycoparasite treated with proteinase revealed OI.-fucose, N-acetyl galactosamine and galactose on its cell surface in addition to the sugars N-acetyl glucosamine and D-glucose. Protoplasts were isolated from hosts and nonhost fungi and their surfaces were examined for sugar distribution patterns. The susceptible host and nonhost protoplast membranes showed all the sugars (N-acetyl glucosamine, D-glucose, (It.-fucose, N-acetyl galactosamine and galactose) tested for. The resistant host protoplast membrane however, had only N-acetyl glucosamine and D-glucose exposed. This sugar distribution profile resembles that exhibited by the untreated resistant host cell wall, as well as that shown by the untreated mycoparasite cell surface. Only susceptible host protoplasts were successful in attaching to the mycoparasite surface. Resistant host protoplasts did not show any interaction with the i mycoparasite cell surface. Both susceptible as well as resistant host protoplasts were incapable of attaching to agarose beads surface-coated with specific carbohydrates. The mycoparasite however, did attach to agarose beads surface-coated with either N-acetyl glucosamine, D-glucose/Dmannose or o:,- methyl-D-mannose. The relevance of the cell wall and the protoplast membrane in the light of the present results, in reacting appropriately to bring about either a susceptible, a resistant or a nonhost response has been discussed.

New conserved vorticity integrals for moving surfaces in multi-dimensional fluid flow

For inviscid fluid flow in any n-dimensional Riemannian manifold, new conserved vorticity integrals generalizing helicity, enstrophy, and entropy circulation are derived for lower-dimensional surfaces that move along fluid streamlines. Conditions are determined for which the integrals yield constants of motion for the fluid. In the case when an inviscid fluid is isentropic, these new constants of motion generalize Kelvin’s circulation theorem from closed loops to closed surfaces of any dimension.

A Note on Ordinally Equivalent Pareto Surfaces

Assuming at least three individuals and some regularity conditions, we construct a set S* of Pareto surfaces which is an ordinal basis of the set S of all surfaces: every surface in S is ordinally equivalent to some surface in S* and all surfaces in S* are ordinally distinct.

Surfaces de Riemann compactes et formule de trace d'Eichler

Dans ce mémoire, nous étudierons quelques propriétés algébriques, géométriques et topologiques des surfaces de Riemann compactes. Deux grand sujets seront traités. Tout d'abord, en utilisant le fait que toute surface de Riemann compacte de genre g plus grand ou égal à 2 possède un nombre fini de points de Weierstrass, nous allons pouvoir conclure que ces surfaces possèdent un nombre fini d'automorphismes. Ensuite, nous allons étudier de plus près la formule de trace d'Eichler. Ce théorème nous permet de trouver le caractère d'un automorphisme agissant sur l'espace des q-différentielles holomorphes. Nous commencerons notre étude en utilisant la quartique de Klein. Nous effectuerons un exemple de calcul utilisant le théorème d'Eichler, ce qui nous permettra de nous familiariser avec l'énoncé du théorème. Finalement, nous allons démontrer la formule de trace d'Eichler, en prenant soin de traiter le cas où l'automorphisme agit sans point fixe séparément du cas où l'automorphisme possède des points fixes.

Comparaison de la force d'adhésion de deux types de résines de collage appliquées sur des surfaces métalliques traitées de différentes façons : une étude in vitro

L’objectif de cette étude était d’évaluer et de comparer la force d’adhésion de deux résines de collage: le ClearfilTM Esthetic Cement & DC Bond Kit (C) et le RelyXTM Unicem (R), sur trois adhérents différents : une surface d’émail, un alliage de métaux non précieux (Np) et un alliage de métaux semi-précieux (Sp). La surface des échantillons des alliages métalliques a subi différents traitements de surface. Sur l’émail (n=15) ainsi que sur les plaquettes d’alliages Np et Sp (n=15), des cylindres de résine étaient appliqués et polymérisés. Suite au processus de collage, les échantillons ont été incubés à 37°C pendant 24 heures, puis ont subi 500 cycles de thermocyclage. Des tests de cisaillement ont été effectués, suivi par l’analyse de la surface des échantillons au microscope à balayage électronique. Une comparaison de type T-test et des comparaisons multiples post hoc, ont été effectuées pour l’analyse statistique (p 0,05). Sur l’émail, les résultats ont démontré que la résine C présentait une force d'adhésion moyenne statistiquement supérieure (33,97±17,18 MPa) à la résine R (10,48±11,23 MPa) (p 0,05). Le type d’alliage utilisé n’influençait pas la force d’adhésion, et ce, peu importe le type de résine de collage (p>0,05). Pour le groupe Sp, la résine C a démontré une adhésion statistiquement supérieure à la résine R, et ce, pour tous les traitements de surface (p 0,05). En conclusion, la résine C a démontré des résultats d’adhésion significativement supérieurs à la résine R sur l’émail ainsi que sur presque toutes les surfaces traitées des alliages de métaux.