The effect of plasma treatment on flexible self-standing supercapacitors composed by carbon nanotubes and multilayer graphene composites

Journal of Materials Science - Flexible self-standing supercapacitor devices (FSSS) have attracted great attention in several areas due to their potential use in a wide range of applications, such...     

Effect of Chenopodium ambrosioides on the healing process of the in vivo bone tissue

The focus of this double‐blind randomized study was on evaluating the effect of an aqueous extract of Mastruz (Chenopodium ambrosioides L.) on the bone repair process in vivo. In total, 36 male Wistar rats were randomly selected for this study, and divided into 3 groups (n = 12): Group HS (Hemostatic Sponge), Group SM (Hemostatic Sponge with Mastruz) and Group BC (Blood Clot). In each animal, bone defects measuring 2 mm in diameter were performed in both tibias for placement of the substances. After 3 and 10 days, the animals were sacrificed, and the tissues were analyzed under an optical microscope relative to the following events: inflammatory infiltrate; necrosis; young fibroblasts; osteoclastic and osteoblastic activity; endosteal and periosteal bone formation; and bone repair. The results were assessed by using Kruskal–Wallis and Mann–Whitney tests (p < .05). Inflammatory infiltrate demonstrated difference between Groups SM and BC in the time interval of 3 days (p = .004); an event related to the presence of the fibrin sponge and liquid of the extract, which induced a foreign body initial reaction. The presence of young fibroblasts (p = .003), osteoclastic (p = .003), and osteoblastic (p = .020) activity was statistically significant between Groups HS and BC in the time interval of 10 days; performance was related to the presence of the sponge within bone. As regards injured bone tissue repair, Group SM demonstrated a higher level of regenerative capacity (p = 0.004), due to a larger quantities of endosteal and periosteal bone formation, demonstrated in Group SM. The aqueous extract of mastruz stimulated bone neoformation, presenting wound closure with bone tissue at the end of 10 days.     

Statistical methodology for pathogen detection

The main goal of the present study was to discuss the application of the McNemar test to the comparison of proportions in dependent samples. Data were analyzed from studies conducted to verify the suitability of replacing a conventional method with a new one for identifying the presence of Salmonella. It is shown that, in most situations, the McNemar test does not provide all the elements required by the microbiologist to make a final decision and that appropriate functions of the proportions need to be considered. Sample sizes suitable to guarantee a test with a high power in the detection of significant differences regarding the problem studied are obtained by simulation. Examples of functions that are of great value to the microbiologist are presented.     

Preparation of monoglycerides by guanidine-catalyzed processes

Glycerolysis of methyl stearate and tristearin has been carried out in the presence of alkylguanidines—strong nonionic bases—as catalysts. When applied at 10 mol%, 1,5,7-triazabicyclo [4.4.0]dec-5-ene, 1,2,3-tricyclohexylguanidine, and 1,3-dicyclohexyl-2-n-octylguanidine give monoglycerides in more than 90% selectivity, in a maximum of 6 h reaction time.     

Investigations on Overall Migration of Various Plastic Materials and Articles Used in Contact with Foodstuffs

The results of overall migration tests for a wide range of plastic packagings and other domestic and imported articles made of plastic intended to come into direct contact with foodstuffs are presented. In these tests the simulants specified in Directive 85/572/EEC as well as isooctane and 95% ethanol (so called alternative substances) have been used. Checking the overall migration into the four simulants specified in the above mentioned Directive it was found that the limit (equal to 10 mg/dm² according to Directive 90/128/EEC) was exceeded in a few, very specific, cases. Comparison between overall migration from some articles into sunflower oil and isooctane was also examined. The results indicate that though the use of isooctane as an alternative substance significantly simplifies the testing procedure, exceeding an overall migration limit into isooctane is not equivalent to exceeding the limit of migration into sunflower oil. In such cases only migration into typical fatty food simulants can have a deciding meaning. © 1997 John Wiley & Sons, Ltd.     

Content of amino acids in fresh and frozen and cooked broad bean seeds (Vicia faba var major) depending on cultivar and degree of maturity

In broad been seeds (cultivars Comprimo RS and Threefoldwhite) harvested at four stages of maturity, which corresponded to dry matter content at the levels of I—25%, II—30%, III—35% and IV—40%, the content of amino acids was determined (g 16 g N⁻¹). The determinations concerned raw broad bean and frozen products cooked for consumption. The content of total and essential amino acids was similar in the two cultivars. With increasing maturity the content of total amino acids and essential amino acids varied, showing a tendency to increase between maturity stages I and IV in all the amino acids, except aspartic acid and alanine in Threefoldwhite. In both cultivars the content of cystine and glutamic acid showed the most rapid rise. Compared with raw broad beans, intact seeds cooked for consumption contained more total amino acids. In products of Comprimo RS the total content of amino acids and essential amino acids was similar in intact seeds and in the dehulled seeds. In products from Threefoldwhite the content of total amino acids and essential amino acids was higher in intact seeds than in dehulled seeds except in the most mature sample where these values were similar. The limiting amino acids were methionine with cystine in both raw broad bean and cooked seeds. © 1999 Society of Chemical Industry     

Microstructural Development of an AlNiBi Alloy and Influence of the Transient Horizontal Solidification Parameters on Microhardness

The combination of the structural and tribological properties presented by AlNiBi alloys has motivated us to establish, as the main objective of this study, the investigation of the microstructural evolution and its influence on the microhardness (HV) of Al-3wt pct Ni-1wt pct Bi alloy horizontally solidified via a water-cooled directional solidification device. Temperature mapping by thermocouples inserted in the metal has been performed for experimental determination of the solidification thermal parameters, such as the growth rate and cooling rate (V_L and T_R, respectively). The microstructure has been characterized by optical and scanning electron microscopy and by microanalysis of the composition via dispersive energy spectroscopy (EDS composition). The macrostructure of the as-solidified ingot is characterized by columnar grains, and the final microstructure consists of an Al-rich primary phase (α-Al) and a eutectic mixture composed of two phases: α-Al + Al₃Ni intermetallic (β) with Bi particles anchored on the β phase. The Bi droplet scale is affected by the thermal parameters. The primary phase (α-Al) is characterized by a reverse cellular-to-dendritic microstructural transition. Cellular and dendritic microstructures have been quantified by the cell, primary dendrite arm, secondary dendrite arm, and tertiary dendrite arm spacings (λ_C, λ₁, λ₂, and λ₃, respectively). The relationships of λ_C, λ₁, λ₂, and λ₃ with V_L and T_R have been established via power-type mathematical expressions. The HV dependence on λ_C, λ₁, λ₂, and λ₃ has been analyzed in both cellular and dendritic microstructural zones. It has been observed that the HV values do not vary in the dendritic zone; however, Hall–Petch’s mathematical equations characterize the HV variation with these thermal and microstructural parameters in the cellular zone.

     

Physicochemical characteristics,proximate analysis and mineral composition of ostrich meat as influenced by muscle

The influence of muscle on the physicochemical characteristics, proximate analysis, and mineral composition of meat from 10 ostriches (10–12 months old), slaughtered according to commercial abattoir procedures, were evaluated. Muscle had no influence (p > 0.05) on L*-values (32.5), a*-values (11.9), water-holding capacity (11.9%), final pH (pH₂₄) values (6.07), and ash contents (1.12 g/100 g edible meat). However, intramuscular lipid contents varied (p < 0.05) from 0.88 (M. fibularis longus) to 1.44 (M. flexor cruris lateralis) g/100 g edible meat, at a mean value of 1.16 g/100 g edible meat for 10 different muscles. Sodium (34.7 mg/100 g edible meat) and iron (3.14 mg/100 g edible meat) contents, both influenced (p < 0.05) by muscle, possessed substantially lower and higher values, respectively, than values reported for beef and chicken.     

Unveiling contamination sources and dissemination routes of Salmonella sp. in pigs at a Portuguese slaughterhouse through macrorestriction profiling by pulsed-field gel electrophoresis

Sixty-nine isolates of Salmonella sp. isolated from the ileum, tonsils, carcass and mandibular and ileocolic lymph nodes of individual pigs slaughtered for consumption in one abattoir were analyzed using serotyping and macrorestriction profiling by Pulsed-Field Gel Electrophoresis (RFLP-PFGE), in order to identify clonal relationships. XbaI macrorestriction was able to distinguish 18 genotypes among the eight identified serotypes: Salmonella Typhimurium (4 genotypes), Salmonella Rissen (3), Salmonella Tennessee (2), Salmonella Enteritidis (2), Salmonella 4,[5],12:i:- (4), Salmonella Give (1), Salmonella Anatum (1), and Salmonella Derby (1). Except for one sample, the serotype and the genotype identified in the samples from the same pork were always the same, allowing to unravel possible dissemination routes of Salmonella sp. through these pork tissues and equate presumptive sources of contamination or infection. Highly significant associations (p < 0.001) were observed for the presence of Salmonella sp. in the ileum and in the ileocolic lymph nodes, as well as between the carcass contamination and the presence of Salmonella sp. in others samples of the correspondent slaughtered pig, such as the ileum, the ileocolic and mandibular lymph nodes and the tonsils. Moreover, 80% of the pigs with ileum and ileocolic lymph nodes positive samples also presented the same salmonella genotype in the correspondent tonsils and, among pigs with positive tonsils, 70% also carried the same genotype in the corresponding mandibular lymph nodes. The occurrence of cross-contamination was also detected, since a genotype identified in other pigs slaughtered in the same day was found in 31% of positive carcasses. The global analysis of the genotypes suggested three different sources of pig infection: the farm of origin, the transportation and the lairage. A particular attention should be paid to the last one, since the majority of the isolates from pig samples were related to infection in the lairage. Since the presence of Salmonella sp. in the ileum of pigs and faeces ingestion promotes tonsils infection and internal dissemination of the agent through the mandibular lymph nodes, as well as drainage to the ileocolic lymph nodes, a potential risk exists at slaughter for Salmonella sp. contamination in the carcasses during pork processing. This risk may be increased by incorrect evisceration techniques and by hygienically inappropriate meat inspection procedures, especially those concerned to the mandibular lymph nodes incisions.     

Learning organisation and human resources management practices: an exploratory research in medium-sized enterprises undergoing a lean implementation

Despite the fact that Lean Manufacturing (LM) implementation has been widely discussed in the literature, a reduced number of works focus on medium-sized enterprises (MEs). Such gap becomes more evident when searching for works exploring the dimensions of learning organisation (DLO) that surround LM implementation in MEs. This paper aims at assessing DLO maturity and the importance of human resources management (HRM) practices in MEs that are starting LM implementation. We verify the applicability of a method for assessing maturity levels of DLO and HRM practices in seven different MEs. The method was originally conceived for large enterprises well advanced in the lean implementation process; it combines concepts of HRM and organisational learning with lean implementation roadmaps. Adapting the method for application in MEs allows such companies to anticipate and minimise organisational learning problems by conducting appropriate HRM practices, leading to a more effective LM implementation. We conclude that the method is a suitable diagnostic tool for MEs, indicating which phases of the lean roadmap are better prepared to be implemented.