In situ characterization of humidity effect on the fatigue damage evolution of a cast aluminium alloy

In this paper, the feedback signal of ultrasonic fatigue system was used to deduce the accumulated fatigue damage in situ using the ultrasonic nonlinearity parameter. It was observed that, compared with the decrease in resonant frequency, the ultrasonic nonlinearity parameter shows a greater sensitivity to fatigue damage evolution (i.e. crack initiation and propagation). Ultrasonic nonlinearity parameters obtained from tests conducted under various environmental humidity levels were monitored and analysed. Through changes in the ultrasonic nonlinearity parameter, it was concluded that both of the fatigue crack initiation life and crack propagation life were reduced by increasing the humidity levels.     

Mapping the evolution of library and information science (1978–2014) using topic modeling on LISA

This paper offers an overview of the bibliometric study of the domain of library and information science (LIS), with the aim of giving a multidisciplinary perspective of the topical boundaries and the main areas and research tendencies. Based on a retrospective and selective search, we have obtained the bibliographical references (title and abstract) of academic production on LIS in the database LISA in the period 1978–2014, which runs to 92,705 documents. In the context of the statistical technique of topic modeling, we apply latent Dirichlet allocation, in order to identify the main topics and categories in the corpus of documents analyzed. The quantitative results reveal the existence of 19 important topics, which can be grouped together into four main areas: processes, information technology, library and specific areas of information application.     

Interface adjustment between poly(ethylene terephthalate) and graphene oxide in order to enhance mechanical and thermal properties of nanocomposites

There is great interest in the use of graphene and derivatives in the production of polymer nanocomposites as it provides improvements in the properties of the materials to which they are associated. Such improvements depend heavily on filler dispersion and the interaction between the nanomaterials and the matrix. This work aimed to study the compatibility of graphene oxide (GO) with a poly(ethylene terephthalate) matrix. For this, graphite was modified using Hummers method, using reaction times of 3 and 6 h. The obtained GO was functionalized with amine, amide, and magnetite groups (FGO). The effects of the oxidation degree, functionalization and concentration of the nanofillers on the dispersion and consequently on the properties of the polymer nanocomposites were evaluated. The nanocomposites were synthesized by the solid–solid deposition method followed by the melt mixing technique. It was observed that lower concentrations of nanofiller associated with the lower degree of oxidation and functionalization improved the interaction of the nanofillers with the matrix, which resulted in better mechanical properties under tensile stresses for strain at break, maximum stress, Young's modulus and toughness. It was also observed that the glass transition and crystallization of nanocomposites increased due to a nucleating effect of the nanofillers.     

Structural Investigation of Diol and Triol Poly(oxypropylene)-Poly(oxyethylene) Block Copolymers Micelles: Composition Dependence,Temperature Response and Clouding Behavior

Solution behavior of two commercially used polyether glycols with poly(oxyethylene) (PEO)-poly(oxypropylene) (PPO)-poly(oxyethylene) (PEO) triblock composition—Diol (linear) and Triol (star-like)—was studied, concerning the concentration and temperature effects until the cloud point (CP). 2-(2-butoxyetoxy) ethanol (DB) increased their miscibility with water. The structural study was performed with 25% DB in water, which produced isotropic solutions at room temperature at all polymer concentrations. Micelle's formation was only observed above 40% of polymer, when reversed micelles were formed. The solvent nuclei of the reversed micelles increased with increasing polymer concentrations, caused by dehydration of the PPO chains, then decreased at further higher concentrations, with completely dehydrated hydrophobic chains. When CP is reached, the solvent nuclei are separated by large polymer domains, without phase separation. Neither ordered nor gel phase was formed, probably due to a combination of high miscibility and short hydrophobic segments. The study was performed by Small-Angle X-ray scattering (SAXS) and complemented by Fourier-transformed infrared spectroscopy (FTIR) and dynamic light scattering (DLS). The main contribution of this work is based on the fact that the knowledge of the solubility behavior of Diol and Triol, by changing the solvent or temperature, opens up new possibilities of their use to phase separation processes in industrial applications and delivery systems. Moreover, the elucidation of mechanisms of solubility allows for the design of novel polyether glycols with tailored solution behavior for efficient performance in its target use. All applications rely on their solution behavior and can be benefited from the present results.     

Multicomponent Petasis‐borono Mannich Preparation of Alkylaminophenols and Antimicrobial Activity Studies

In this work we report the antibacterial activity of alkylaminophenols. A series of such compounds was prepared by a multicomponent Petasis‐borono Mannich reaction starting from salicylaldehyde and its derivatives. The obtained compounds were tested against a large panel of microorganisms, Gram‐positive and Gram‐negative bacteria, and a yeast. Among the several tertiary amine derivatives tested, indoline‐derived aminophenols containing a nitro group at the para‐phenol position showed considerable activity against bacteria tested with minimal inhibitory concentrations as low as 1.36 μm against Staphyloccocus aureus and Mycobacterium smegmatis. Cytotoxicity of the new para‐nitrophenol derivatives was observed only at concentrations much higher than those required for antibacterial activity.     

CA-125 and carcinoembryonic antigen assay vs. cytodiagnostic experience in the classification of benign ovarian cysts

OBJECTIVE: To compare the relative strengths of two factors involved in making an accurate differentiation between functional and epithelial ovarian cysts, along with their combination: (1) the cytologist's level of experience in interpreting ovarian cytology, (2) the use of the tumor markers carcinoembryonic antigen (CEA) and CA-125 in cyst fluid, and (3) a combination of (1) and (2). STUDY DESIGN: Papanicolaou-stained sediments from fluid aspirated from 31 resected ovarian cysts (6 functional and 25 epithelial) were blindly and independently evaluated by five pathologists with varying experience in ovarian cytology. Cyst fluid supernatant was used for CEA, enzyme-linked immunosorbent assay, and CA-125 radioimmunoassay; CEA levels > 5 ng/mL or CA-125 > 5,000 U/mL were considered elevated. Cysts were categorized cytologically and histologically as functional or epithelial and by tumor markers as "neither elevated" or "either or both elevated" (EBE). RESULTS: The agreement of histologic diagnosis with each pathologist's cytologic diagnosis ranged from 53% to 84% (53%, 71%, 83%, 82%, 84%), corresponding to increasing level of experience. The percentage of agreement with EBE was 77%, whereas combined experienced pathologist's diagnosis and EBE was 87%. Kappa equaled .45 for experienced cytopathologist's diagnosis or EBE alone. Kappa equaled .53 when the pathologist or EBE diagnosed an epithelial cyst, indicating results unlikely to occur by chance. CONCLUSION: The distinction of functional from epithelial ovarian cysts is best achieved by combining measurement of the tumor markers CEA and CA-125 with a high level of cytopathology experience.     

CD40/CD40 ligand interactions in normal, reactive and malignant lympho-hematopoietic tissues

CD40 is a 48 Kd integral membrane protein expressed by cells of B cells, origin, dentritic cells, monocytes, epithelial cells, endothelial cells and tumor cells including carcinomas, B cell lymphomas/leukemias and Hodgkin and Reed-Sternberg (HRS) cells of Hodgkin's disease (HD). CD40 has been clustered as a member of the nerve growth factor (NGF)/tumor necrosis factor (TNF) receptor superfamily with the corresponding counterstructure, the CD40 ligand (L) being mainly expressed by activated CD4+ T cells, but also some activated CD8+ T cells, basophils, eosinophils, mast cells and stromal cells. CD40L shares significant amino acid homology with TNF particularly in its extracellular domain ("TNF homology region") and is therefore viewed as a member of the TNF ligand superfamily. Binding of CD40L+ T cells to CD40+ B cells is thought to play a major role in T cell-dependent B cell activation, B cell proliferation, Ig isotype switching, memory B cell formation and rescue of B cells from apoptotic death in germinal centers. Mutations of the CD40L gene have been associated with the X-linked hyper-IgM immunodeficiency syndrome, pointing to the critical role of the CD40/CD40L interaction in the T cell-B cell interplay. Accordingly, expression of CD40 by human lympho-hematopoietic tumors has been shown in most of the B cell neoplasias, H-RS cells and HD and some carcinomas. In contrast, CD40L+ tumor cells are almost invariably restricted to CD4+/CD8- T cell lymphomas. Overall, functional CD40/CD40L interactions appear to be critical for cellular activation signals during immune responses and neoplastic tumor cell growth. The understanding of the biology of CD40L has improved our diagnostic and therapeutic repertoire in the management of several human diseases, including CD40+ tumors.     

The kinetics of cooked meat haemoprotein formation in meat and model systems

The rate of cooked meat haemoprotein formation (measured as the rate of loss of myoglobin solubility) was found, at least initially, to obey first order kinetics in meat, aqueous muscle extracts and mixtures of myoglobin and bovine serum albumin. In meat at 60 °C the rate was dependent on the species, (the pigment was formed significantly faster in lamb m. longissimus dorsi than in beef m. longissimus dorsi) and anatomical location (cooked meat haemoprotein was formed in beef m. 1. dorsi about twice as rapidly as in both beef shin and chuck (shoulder) muscle of similar pH). The rate of formation was similar in aqueous muscle extracts to that found in meat and in these systems increased with decreasing pH. The activation energies for all beef systems studied were similar and typical of those associated with protein denaturation (˜300 KJ mol⁻¹); however, that from lamb appeared to be lower (˜200 KJ mol⁻¹). The problems of using colour as an index of temperature reached, either for microbial safety (E. Coli 0157:H7 destruction) or quality are discussed in the light of these results.     

Biofilm growth and hydrodynamic behaviour in the biological plate tower (BPT) with and without hanging biomass (BPT-HB)

Deodorization and volatile organic compound abatement from polluted air streams can be accomplished with the biological plate tower (BPT), which has proved to be a reliable alternative to biofilters and biotrickling filters. Unlike those, the BPT is a non-clogging device, with constant active surface, and steady performance, making it ideal for scale-up and modelling. The initial BPT design needed improvement for better performance. The cylindrical body (circular plates) was replaced by a rectangular cuboid (rectangular plates). Holes in the plates did augment the amount of active biomass (hanging from the holes and under the plates), without reducing the transfer of toluene from the gaseous to the liquid phase. The diminished distance between plates was well tolerated in co-current flow, allowing much higher quantities of biomass in the same reactor volume. With 18 and 14 mm spacing between adjacent plates, the BPT, with and without holes, was tested for flooding, holdup and pressure drop. Several gas and liquid flows were tested, both in co-current and counter-current. In hydrodynamic terms, the BPT-HB with co-current flow was clearly the best option. Higher stability with higher flow rates, and lower pressure drops were observed. The inoculum was obtained from wastewater plant activated sludge (petrochemical industry).