1,175 research outputs found

    Twinfilin is required for actin-dependent developmental processes in Drosophila

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    The actin cytoskeleton is essential for cellular remodeling and many developmental and morphological processes. Twinfilin is a ubiquitous actin monomer-binding protein whose biological function has remained unclear. We discovered and cloned the Drosophila twinfilin homologue, and show that this protein is ubiquitously expressed in different tissues and developmental stages. A mutation in the twf gene leads to a number of developmental defects, including aberrant bristle morphology. This results from uncontrolled polymerization of actin filaments and misori-entation of actin bundles in developing bristles. In wildtype bristles, twinfilin localizes diffusively to cytoplasm and to the ends of actin bundles, and may therefore be involved in localization of actin monomers in cells. We also show that twinfilin and the ADF/cofilin encoding gene twinstar interact genetically in bristle morphogenesis. These results demonstrate that the accurate regulation of size and dynamics of the actin monomer pool by twinfilin is essential for a number of actin-dependent developmental processes in multicellular eukaryotes

    Vuorovaikutus Kelan puhelinpalvelussa

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    Neural network design and feature selection using principal component analysis and Taguchi method for identifying wood veneer defects

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    Nowadays, ensuring high quality can be considered the main strength for a company’s success. Especially, in a period of economic recession, quality control is crucial from the operational and strategic point of view. There are different quality control methods and it has been proven that on the whole companies using a continuous improvement approach, eliminating waste and maximizing productive flow, are more efficient and produce more with lower costs. This paper presents a method to optimize the quality control stage for a wood manufacturing firm. The method is based on the employment of the principal component analysis in order to reduce the number of critical variables to be given as input for an artificial neural network (ANN) to identify wood veneer defects. The proposed method allows the ANN classifier to identify defects in real time and increase the response speed during the quality control stage so that veneers with defects do not pass through the whole production cycle but are rejected at the beginning

    The Effects of Cleaning on the Kinetics of in vitro Metal Release from Dental Casting Alloys

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    The kinetics of the release of elements from six dental casting alloys into cell-culture medium was assessed by means of atomic absorption spectroscopy. Alloys were evaluated in the polished and polished-cleaned conditions so that the effects of cleaning could be determined. Auger scanning microscopy was used for analysis of the surfaces of selected alloys before and after exposure to the cell-culture medium. Release patterns for each element were characterized by the shape of the dissolution us. time curve, concentration of the element at 12 h as a percentage of the 72-hour concentration, and the relative slope of the curve from 48 to 72 h. Three patterns of release were observed for elements in these alloys. Type I patterns had logarithmic shapes with relatively large 12-hour concentrations and low 48-72-hour slopes. Type II patterns had logarithmic shapes but with moderate 12-hour concentrations and 48-72-hour slopes. Type III patterns were polynomial in shape, had relatively low 12-hour concentrations, and had large 48-72-hour slopes. Cleaning did not change the pattern of release but did generally significantly decrease the quantities of elements released (p = 0.05). The type of dissolution vs. time curve appeared to be dependent upon the element and the composition of the alloy. When cleaning reduced dissolution, surface analyses showed that the cleaning process increased the abundance of elements such as Au and Pd and reduced the abundance of Ag and Cu. Elements which were released from the alloys were more abundant on the surface than in the bulk in both polished and polished-cleaned conditions. Auger analyses of alloy surfaces after exposure to medium showed the presence of organic films up to 50 nm thick. This study demonstrated the importance of consideration of the cleaning method and kinetic release pattern when in vitro tests which assess the cytotoxicities of these alloys are planned.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67010/2/10.1177_00220345920710071101.pd

    Catheter-Directed Thrombolysis Versus Pharmacomechanical Thrombectomy for Upper Extremity Deep Venous Thrombosis : A Cost-Effectiveness Analysis

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    Background: Upper extremity deep vein thrombosis represents (UEDVT) 2-3% of all deep vein thrombosis. Catheter directed thrombolysis (CDT) was replaced largely by pharmacomechanical thrombolysis (PMT) in our institution. In this study we compared the immediate and 1-year results as well as the total hospital costs between CDT and PMT in the treatment of UEDVT. Methods: From 2006 to 2013, 55 patients with UEDVT were treated with either CDT or PMT at Helsinki University Hospital. Of them, 43 underwent thoracoscopic rib resection later to relieve phlebography-confirmed vein compression. This patient cohort was prospectively followed up with repeated phlebographies. CDT was performed to 24 patients, and 19 had PMT with a Trellis (TM) device. Clinical evaluation and vein patency assessment were performed with either phlebography or ultrasound 1 year after the thrombolysis. Primary outcomes were immediate technical success, 1-year vein patency, and costs of the initial treatment. Results: The immediate overall technical success rate, defined as recanalization of the occluded vein and removal of the fresh thrombus, was 91.7% in the CDT group and 100% in the PMT group (n.s.). The median thrombolytic time was significantly longer in CDT patients than that in PMT patients (21.1 vs. 0.33 hr, P <0.00001). There were no procedure-related complications. The 1-year primary assisted patency rate was similar in both the groups (91.7% and 94.7%). There were no recurrences of clinical DVT. The hospital costs for the acute period were significantly lower in the PMT group than those in the CDT group (medians: 11,476 (sic) and 5,975 (sic) in the CDT and PMT groups, respectively [P <0.00001]). Conclusions: The clinical results of the treatment of UEDVT with CDT or PMT were similar. However, PMT required shorter hospital stay and less intensive surveillance, leading to lower total costs.Peer reviewe

    The effect of mineral supplements on resorption in the digestive tract of cattle, with special reference to Bolus alba

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    Fourteen sexually mature heads of cattle were divided into two groups; Group I receiving mineral mixture A, containing 15 % of Bolus alba, while Group II were given mixture B, containing no Bolus alba, but 10 % more Ca. Otherwise, both groups received the same feeding. Samples of blood and faeces of the animals were taken monthly for the determination of phosphorus, respectively phosphorus and carotenes. The experiment lasted one stabling period. In Group I, the mean inorganic phosphorus values of the blood were 6.7 mg/100 ml. and in Group 11, 6.1 mg/100 ml. The mean phosphorus values of the faeces were 8.8 gr/kg dry matter in Group I and in Group II, 9.3 gr/kg dry matter. The mean carotene values in Group I were 98.3 mg/kg dry matter and in Group II, 96.3 mg/kg dry matter. However, none of these differencies is statistically significant. On the basis of the present investigation it can be concluded that Bolus alba exerts no detrimental influence on the resorption of phosphorus and carotenes in the digestive tract of cattle
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