Culture of bovine ovarian follicle wall sections maintained the highly estrogenic profile under basal and chemically defined conditions

Follicle cultures reproduce in vitro the functional features observed in vivo. In a search for an ideal model, we cultured bovine antral follicle wall sections (FWS) in a serum-free defined medium (DM) known to induce 17β-estradiol (E2) production, and in a nondefined medium (NDM) containing serum. Follicles were sectioned and cultured in NDM or DM for 24 or 48 h. Morphological features were determined by light microscopy. Gene expression of steroidogenic enzymes and follicle-stimulating hormone (FSH) receptor were determined by RT-PCR; progesterone (P4) and E2 concentrations in the media were measured by radioimmunoassay. DM, but not NDM, maintained an FWS morphology in vitro that was similar to fresh tissue. DM also induced an increase in the expression of all steroidogenic enzymes, except FSH receptor, but NDM did not. In both DM and NDM, there was a gradual increase in P4 throughout the culture period; however, P4 concentration was significantly higher in NDM. In both media, E2 concentration was increased at 24 h, followed by a decrease at 48 h. The E2:P4 ratio was higher in DM than in NDM. These results suggest that DM maintains morphological structure, upregulates the expression of steroidogenic enzyme genes, and maintains steroid production with a high E2:P4 ratio in FWS cultures.

Cell wall polysaccharides of common beans (Phaseolus vulgaris L.)

The soluble and insoluble cotyledon (SPF-Co and IPF-Co) and tegument (SPF-Te and IPF-Te) cell wall polymer fractions of common beans (Phaseolus vulgaris) were isolated using a chemical-enzymatic method. The sugar composition showed that SPF-Co was constituted of 38.6% arabinose, 23.4% uronic acids, 12.7% galactose, 11.2% xylose, 6.4% mannose and 6.1% glucose, probably derived from slightly branched and weakly bound polymers. The IPF-Co was fractionated with chelating agent (CDTA) and with increasing concentrations of NaOH. The bulk of the cell wall polymers (29.4%) were extracted with 4.0M NaOH and this fraction contained mainly arabinose (55.0%), uronic acid (18.9%), glucose (10.7%), xylose (10.3%) and galactose (3.4%). About 8.7% and 10.6% of the polymers were solubilised with CDTA and 0.01M NaOH respectively and were constituted of arabinose (52.0 and 45.9%), uronic acids (25.8 and 29.8%), xylose (9.6 and 10.2%), galactose (6.1 and 3.9%) and glucose (6.5 and 3.8%). The cell wall polymers were also constituted of small amounts (5.6 and 7.2%) of cellulose (CEL) and of non-extractable cell wall polymers (NECW). About 16.8% and 17.2% of the polymers were solubilised with 0.5 and 1.0M NaOH and contained, respectively, 92.1 and 90.7% of glucose derived from starch (IST). The neutral sugar and polymers solubilization profiles showed that weakly bound pectins are present mainly in SPF-Co (water-soluble), CDTA and 0.01-0.1M NaOH soluble fractions. Less soluble, highly cross-linked pectins were solubilised with 4.0M NaOH. This pectin is arabinose-rich, probably highly branched and has a higher molecular weight than the pectin present in SPF-Co, CDTA and 0.01-0.1M NaOH fractions.

The adherence of Pseudomonas fluorescens to marble, granite, synthetic polymers, and stainless steel

The adherence of Pseudomonas fluorescens cells to nine food-processing contact surfaces was evaluated using the plate-count method. The surfaces include marble, granite, stainless steel, polyvinyl chloride, polyurethane, and silicone-coated cloth, which have been used only in a few studies concerning bacterial adherence. The number of cells adhered to the surfaces increased with contact time reaching 5.0-6.1 log CDM.cm-2 after 10 hours, which can be considered a well established adherence process. The number of adhered cells doubled in 29.5 minutes and 23.5 minutes on stainless steel and thin polyvinyl chloride-coated cloth, respectively. For the other surfaces, this value was 9.8 minutes on average. Marble, granite, thick polyvinyl-coated cloth, double-faced rugous polyurethane, and silicone-coated cloth were not different (p < 0.05) in their ability to adhere cells (CFU/cm²) after 2 and 10 hours. The surfaces that had higher percentage of similarity in the adhesion level and higher log CFU/cm² of adhered cells were double-faced rugous polyurethane, silicone-coated cloth, and granite. The surfaces showed very different microtopography characteristics when viewed using scanning electron microscopy. This experiment showed the importance of using appropriate materials for food contact during processing, which will affect the cleaning and sanitation procedures.

Sensory profile of 'Douradão' peaches cold stored under controlled atmosphere

The sensory quality of 'Douradão' peaches cold stored in three different conditions of controlled atmosphere (CA1, CA2, CA3 and Control) was studied. After 14, 21 and 28 days of cold storage, samples were withdrawn from CA and kept for 4 days in ambient air for ripening. The sensory profile of the peaches and the descriptive terminology were developed by methodology based on the Quantitative Descriptive Analysis (QDA). The panelists consensually defined the sensory descriptors, their respective reference materials and the descriptive evaluation ballot. Fourteen panelists were selected based on their discrimination capacity and reproducibility. Seven descriptors were generated showing similarities and differences between samples. The data were analyzed by ANOVA, Tukey test and Principal Component Analysis (PCA). Results showed significant differences in the sensory profiles of the peaches. The PCA showed that CA2 and CA3 treatments were more characterized by the fresh peach flavor, fresh peach appearance, juiciness and flesh firmness, and were effective in keeping the good quality of the 'Douradão' peaches during the 28 days of cold storage. The Control and CA1 treatments were characterized by the mealiness and were ineffective for quality maintenance of the fruits during cold storage.

Microstructural changes of frozen strawberries submitted to pre-treatments with additives and vacuum impregnation

Strawberries were submitted to freezing after pre-treatments with hydrocolloid and calcium salts (pectin and calcium chloride) at different concentrations, in the attempt to establish a correlation of the effects of these substances and their processing, on the physical and microstructural characteristics of fruits after thawing. Strawberry halves were submitted to impregnation with controlled vacuum pressure of 84.4, 50.5 and 16.6 kPa; comprising pectin at concentrations of 0, 1.5 and 3%; with the addition of calcium chloride at concentrations of 0, 3 and 6%; and glucose at 20%, for 4 hours. Measurements were made of the total soluble solid contents, cellular fluid loss, texture and viscosity of the solution, before and after the freezing/thawing. Images of the tissue cuts during the freezing, in function of time, were taken in an optic microscope coupled to a cold-stage and controlled temperature system, where the reduction of the cellular area was quantified using an image analyzing software. The pectin concentration had an influence on and demonstrated a potential for protection of the frozen tissue samples. The photomicrographs showed that the loss of cellular fluid occurs during the growth of ice formed in the intercellular spaces and it is retarded through treatments with high pectin concentrations.

Determination of presence and quantification of cadmium, lead and copper in Nile tilapia (Oreochromis niloticus) fillets obtained from three cold storage plants in the state of Parana, Brazil

Pisciculture is an economic activity that is steadily growing in the state of Parana, Brazil, and Nile tilapia (Oreochromis niloticus) is one of the widely cultivated species in this state. Tilapia is not only a very nutritious food, but also an important indicator of environmental contamination. This study aimed to verify contamination by cadmium, copper and lead in tilapia fillets, and to compare the found values to international legislations. Were collected 135 samples of tilapia fillets, between July 2006 and May 2007, in three fish stores located in regions west and north of Paraná State. Samples of tilapia fillet were analyzed in relation to the presence of cadmiun, lead and copper, using atomic absorption spectrophotometry. Lead has not been detected in the analyses. Cadmium has been detected in three samples, on concentrations of 0.012 µg.g-1, 0.011 µg.g-1 and 0.014 µg.g-1. Copper has been detected in all fillets, and the average concentration of each cold storage plant was of 0.122 µg.g-1, 0.106 µg.g-1 and 0.153 µg.g-1. The concentrations found in this study are within the limits allowed by both the European and the Australian legislations.

Effect of adding unconventional raw materials on the technological properties of rice fresh pasta

The aim of this study was to develop fettuccini type rice fresh pasta by cold extrusion. To produce the pasta, a 2² Central Composite Rotational Design was used, in which the effects of the addition of pre-gelatinized rice flour - PGRF (0-60%) and modified egg albumin - MEA (0-10%) were studied. The dependent variables were the results of the cooking test and of the instrumental texture. The optimum cooking time for all of the formulations of rice fresh pasta was 3 minutes. MEA had a greater effect on increasing the weight of the pasta when compared to that of PGRF. It was found that with the addition of PGRF increase in loss of solids in cooking water, whereas MEA exerted the opposite effect on this parameter. Moreover, the maximum value of MEA (10%) had an optimum effect on pasta firmness, while PGRF had a negative effect on this parameter. The maximum values of PGRF and MEA reduced the stickiness of the pasta. Based on these results and on the parameters considered as most important, the rice pasta with the best technological characteristics was that with the maximum levels of MEA (10%) and no addition of PGRF (0%). This product was submitted to sensory and microbiological analyses, with good results.

Characterization of new sources of derivative starches as wall materials of essential oil by spray drying

Starch derivatives of taro (Colocasia esculenta L. Schott) and rice were characterized as wall materials of orange oil (d-limonene) by spray drying. Native starches were initially hydrolyzed with HCl and then esterified. Succinylated starches were modified using a conventional method in a slurry and were extruded; whereas, the phosphorylated starches were modified using the extrusion process. Viscosity and solubility of starches reduced after acid hydrolysis, derivatization, and extrusion. The particle size of the wall materials ranged between 20.05 and 31.81 µm. The encapsulation efficiency of the phosphorylated taro, rice, and waxy corn starches was 96.9, 96.8 and 97.1% respectively, and 98.6, 98.1, and 98.8% for succynilated taro, rice, and waxy corn starches, respectively. Starch derivatives of taro and rice could potentially be used as wall materials of orange oil d-limonene.

Determination of some quality properties of marinated sea bream (Sparus Aurata L., 1758) during cold storage

In this study, it was aimed to determine the effect of sea bream (Sparus aurata) marinated some quality properties during cold storage. The fillets of fish were immersed into brine including 3.5% acetic acid 11% salt in the ratio of 1: 1.5 (fish: marinate brine) for marination process. After the process of ripening, samples were grouped into two and packed in plastic containers; one being plain (in sunflower oil) and the other being sauced (sauced prepared with sunflower oil). During storage, sensory, crude protein, lipid, dry matter and crude ash, TBA, TVB-N, TMA-N and peroxide analyses were done periodically. According to results of 200 days of storage, TVB-N values of sea bream marinates packaged as plain and sauced were 15.86/14.89 mg/100g, TBA 7.06/7.99 mg MA/kg, TMA-N 2.97/3.12, mg/100g, the value of peroxide was 7.23/7.45 meq/kg respectively. According to chemical and sensory analyses results obtained in the study; it was concluded that sea bream marinates packaged as plain and sauced can be stored in +4 °C for 200 days.

Microbiological and sensory evaluation of Jambu (Acmella oleracea L.) dried by cold air circulation

Abstract The aim of this study was to evaluate the microbiological and sensory quality of the Jambu (Acmella oleracea L.) in natura and dried by cold air, and the determination of its drying curve. The microbiological analysis were performed to Salmonella spp, the coagulase-positive Staphylococcus, and coliforms in the both Jambu samples, at 45 °C. Tacacá, the typical food dish of Pará state, Brazil, has showed good consumer global acceptance in the sensory evaluation of Jambu in natura (score of 8.00 ± 1.46) and dried (score of 8.67 ± 0.66). Both samples, Jambu in natura and dried by cold air, were by the current legislation regarding the microbiological aspects, this is the absence of Salmonella spp, coagulase-positive Staphylococcus <1×101 CFU/g, and coliforms <3 MPN/g, at 45 °C. Thus, considering sensory and health aspects, the commercialization of dried Jambu becomes viable, facilitating its transportation and handling, as well as for reducing its vegetable mass.

Simulation and material calibration of ultra high strength steel (UHSS) S960 welded joint under static tensile test utilizing finite element method (FEM)

The aim of this work was to calibrate the material properties including strength and strain values for different material zones of ultra-high strength steel (UHSS) welded joints under monotonic static loading. The UHSS is heat sensitive and softens by heat due to welding, the affected zone is heat affected zone (HAZ). In this regard, cylindrical specimens were cut out from welded joints of Strenx® 960 MC and Strenx® Tube 960 MH, were examined by tensile test. The hardness values of specimens’ cross section were measured. Using correlations between hardness and strength, initial material properties were obtained. The same size specimen with different zones of material same as real specimen were created and defined in finite element method (FEM) software with commercial brand Abaqus 6.14-1. The loading and boundary conditions were defined considering tensile test values. Using initial material properties made of hardness-strength correlations (true stress-strain values) as Abaqus main input, FEM is utilized to simulate the tensile test process. By comparing FEM Abaqus results with measured results of tensile test, initial material properties will be revised and reused as software input to be fully calibrated in such a way that FEM results and tensile test results deviate minimum. Two type of different S960 were used including 960 MC plates, and structural hollow section 960 MH X-joint. The joint is welded by BöhlerTM X96 filler material. In welded joints, typically the following zones appear: Weld (WEL), Heat affected zone (HAZ) coarse grained (HCG) and fine grained (HFG), annealed zone, and base material (BaM). Results showed that: The HAZ zone is softened due to heat input while welding. For all the specimens, the softened zone’s strength is decreased and makes it a weakest zone where fracture happens while loading. Stress concentration of a notched specimen can represent the properties of notched zone. The load-displacement diagram from FEM modeling matches with the experiments by the calibrated material properties by compromising two correlations of hardness and strength.

Transmission oflight through individually formed fiber- reinforced composite post (Yksilöllisesti muotoillun kuitukomposiittinastan valonläpäisevyys)

Kuitukomposiitista valmistettuja juurikanavanastoja käytetään apuna, kun restauroidaan juurihoidettuja ja kruunuosastaan runsaasti kudosta menettäneitä hampaita. Kliinisen kestävyyden kannalta on tärkeää että nasta kiinnittyy hampaaseen hyvin. Tarvittavan valomäärän saattaminen valokovetuksella pimeään juurikanavaan on vaikeaa ja sen vuoksi nastojen kiinnittämiseen suositellaan kaksoiskovetteista yhdistelmämuovisementtiä, joka kovettuu vain osittain valolla. Jotta nasta ja sementti polymeroituisivat hyvin, nastan hyvä valonläpäisy- ja sirontakyky olisi eduksi. Tehdasvalmisteisten nastojen valonläpäisykyvyn on todettu heikkenevän niiden pituuden kasvaessa. Yksilöllisesti muotoilluilla kuitukomposiittinastoilla, joilla on osittaislomittaismuoviverkostorakenne (semi-IPN) polymeerimatriisi, on todettu tehdasvalmisteisia kuitunastoja parempi sidos nastan ja yhdistelmämuovisementin välillä. Yksilöllisesti muotoilluilla kuitunastoilla näyttäisi myös olevan hyvä valonjohtamiskyky, mutta lisätutkimuksia tarvitaan. Tässä tutkimuksessa selvitettiin yksilöllisesti muotoillun kuitukomposiittinastan (EverStick Post) ja kahden tehdasvalmisteisen (Relyx Fiber Post ja GC Fiber Post) kuitukomposiittina stan valonläpäisevyyttä sekä pituuden vaikutusta niiden valonläpäisykykyyn laboratorio- olosuhteissa. Tutkimushypoteesi oli, että nastojen valonläpäisykyky heikkenee niiden pidentyessä. Tutkimuksessa kaikista nastatyypeistä valmistettiin eripituisia nastoja (4, 8, 12 ja 16 mm). Nastoille tehtiin samanpituiset testikappaleet muoviputkesta ja polyvinyylisiloksaanista, ja nastat asetettiin niiden sisään. Tämän jälkeen nastoja kovetettiin valokovettimella 10 sekuntia, ja läpi päässyt valo mitattiin MARC Resin Calibrator -laitteella. Kontrollina käytettiin tyhjää testikappaletta ilman nastaa. Keskeiseksi tulokseksi saatiin, että yksilöllisesti muotoillulla kuitukomposiittinastalla oli kaikissa pituusryhmissä muita nastoja merkitsevästi parempi valonläpäisykyky. Tulokset osoittivat myös, että kaikkien nastojen valonläpäisevyys laski merkitsevästi nastan pituuden lisääntyessä aina 12 millimetriin asti. Tulosten perusteella yksilöllisesti muotoillulla kuitukomposiittinastalla on tehdasvalmisteista nastaa parempi valonläpäisykyky. Kuitukomposiittinastojen valonläpäisykyky heikkenee niiden pituuden kasvaessa aiempien tutkimusten mukaisesti. Jatkotutkimuksissa tulisi selvittää, miten valonläpäisevyys ja siroaminen vaikuttavat nastan ja sementin polymeroitumiseen ja siten kliiniseen lopputulokseen.

A modified nominal stress method for fatigue assessment of steel plates with thermally cut edges

Thermal cutting methods, are commonly used in the manufacture of metal parts. Thermal cutting processes separate materials by using heat. The process can be done with or without a stream of cutting oxygen. Common processes are Oxygen, plasma and laser cutting. It depends on the application and material which cutting method is used. Numerically-controlled thermal cutting is a cost-effective way of prefabricating components. One design aim is to minimize the number of work steps in order to increase competitiveness. This has resulted in the holes and openings in plate parts manufactured today being made using thermal cutting methods. This is a problem from the fatigue life perspective because there is local detail in the as-welded state that causes a rise in stress in a local area of the plate. In a case where the static utilization of a net section is full used, the calculated linear local stresses and stress ranges are often over 2 times the material yield strength. The shakedown criteria are exceeded. Fatigue life assessment of flame-cut details is commonly based on the nominal stress method. For welded details, design standards and instructions provide more accurate and flexible methods, e.g. a hot-spot method, but these methods are not universally applied to flame cut edges. Some of the fatigue tests of flame cut edges in the laboratory indicated that fatigue life estimations based on the standard nominal stress method can give quite a conservative fatigue life estimate in cases where a high notch factor was present. This is an undesirable phenomenon and it limits the potential for minimizing structure size and total costs. A new calculation method is introduced to improve the accuracy of the theoretical fatigue life prediction method of a flame cut edge with a high stress concentration factor. Simple equations were derived by using laboratory fatigue test results, which are published in this work. The proposed method is called the modified FAT method (FATmod). The method takes into account the residual stress state, surface quality, material strength class and true stress ratio in the critical place.

Analysis and guidelines for implementation of EN 1090-2 Standard to assist execution class assignment of steel structures

Finnish design and consulting companies are delivering robust and cost-efficient steel structures solutions to a large number of manufacturing companies worldwide. Recently introduced EN 1090-2 standard obliges these companies to specify the execution class of steel structures for their customers. This however, requires clarifying, understanding and interpreting the sophisticated procedure of execution class assignment. The objective of this research is to provide a clear explanation and guidance through the process of execution class assignment for a given steel structure and to support the implementation of EN 1090-2 standard in Rejlers Oy, one of Finnish design and consulting companies. This objective is accomplished by creating a guideline for designers that elaborates on the four-step process of the execution class assignment for a steel structure or its part. Steps one to three define the consequence class (projected consequences of structure failure), the service category (hazards associated with the service use exploitation of steel structure) and the production category (manufacturing process peculiarities), based on the ductility class (capacity of structure to withstand deformations) and the behaviour factor (corresponds to structure seismic behaviour). The final step is the execution class assignment taking into account results of previous steps. Main research method is indepth literature review of European standards family for steel structures. Other research approach is a series of interviews of Rejlers Oy representatives and its clients, results of which have been used to evaluate the level of EN 1090-2 awareness. Rejlers Oy will use the developed novel coherent standard implementation guideline to improve its services and to obtain greater customer satisfaction.