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This work evaluates the enzymatic hydrolysis of starch from cassava using pectinase, α-amylase, and amyloglucosidase. A central composite rotational design (CCRD) was carried out to evaluate the effects of amyloglucosidase, pectinase, reaction time, and solid to liquid ratio. All the experiments were carried out in a bioreactor with working volume of 2 L. Approximately 98% efficiency hydrolysis was obtained, resulting in a concentration of total reducing sugar released of 160 g/L. It was concluded that pectinase improved the hydrolysis of starch from cassava. Reaction time was found to be significant until 7 h of reaction. A solid to liquid ratio of 1.0 was considered suitable for hydrolysis of starch from cassava. Amyloglucosidase was a significant variable in the process: after its addition to the reaction media, a 30%–50% increase in the amount of total reducing sugar released was observed. At optimal conditions the maximum productivity obtained was 22.9 g/(L·h).  相似文献   
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Introduction:

Respiratory syncytial virus (RSV) infection is the most common cause of hospitalization in infants and small children. The aim was to present a 13-months old boy diagnosed with acute airway infection, acute otitis media (AOM) and hepatitis during the RSV-infection.

Material and methods:

Serum catalytic activities of alkaline phosphatase (ALP), aspartate aminotranspherase (AST), alanine aminotranspherase (ALT), gamma glutamyl transpherase (GGT), lactate dehydrogenase (LD), and concentrations of bilirubin were monitored during hospitalization and at control examination.

Results:

The child had clinical signs and symptoms of respiratory failure, AOM, and laboratory findings of virus infection and liver disease. On admission, catalytic activities of enzymes were markedly increased, especially the activity of ALP (10333 U/L, i.e. 24-fold increase in comparison with the upper reference limit). The highest increased in AST (339 U/L, 4.5-fold), ALT (475 U/L, 10.3-fold) and LD (545 U/L, 1.5-fold) were registered on the 3rd day, and the highest increase in GGT (68 U/L, 3.1-fold) occurred on the 11th day. Seven weeks after discharge AST, ALT, GGT and LD decreased into reference range, and ALP remain mildly increased (478 U/L, 1.1 fold increase). RSV was confirmed in nasal lavage fluid.

Conclusion:

Laboratory results in patient with RSV infection needs to be interpreted in the light of both, respiratory and extrapulmonary manifestations of the infection, respectively.  相似文献   
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Research Findings: Empathy, or the ability to understand what others are thinking or feeling, can be observed in early developmental stages. The purpose of this study was to validate the Spanish version of the Empathy Questionnaire (EmQue) and examine its longitudinal measurement invariance (LMI) at 2 time points. Parents of 103 children completed the EmQue when their children were 3 (M = 41.76) and 4 (M = 51.65) years old. Confirmatory factor analyses revealed that Grazzani, Ornaghi, Pepe, Brazzelli and Rieffe’s (2016) 3-factor model of emotional contagion (EC), attention to others’ feelings, and prosocial actions (PA) presented the best fit indices at both time points (Time 1: CFI = .931, TLI = .914, and RMSEA = .070; Time 2: CFI = .941, TLI = .935, and RMSEA = .064). Moreover, preliminary evidence was obtained for the LMI of this model. PA scores increased over time. Score reliability ranged from .60 (EC) to .83 (PA). Positive correlations were found between PA and emotional regulation at each time point and across time.Practice or Policy: The great relevance of empathy and prosocial behavior in academic achievement and psychological adjustment justifies the development of reliable instruments to evaluate these constructs from early ages.  相似文献   
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Stroke in children is a heterogeneous disorder. Over 100 risk factors for stroke have been reported and genetic predisposition to stroke has been established. The most frequently reported risk factors are congenital heart malformations, hemolytic anemias, collagen vascular diseases, some rare inborn metabolic disorders, trauma, infection and thrombophilia. The aim of this article is to provide an overview of investigated inherited prothrombotic risk factors in children with first ischemic stroke. Various prothrombotic risk factors have been investigated in pediatric stroke including elevated homocysteine and lipoprotein (a), antithrombin, protein C and protein S deficiency, Factor V Leiden, Factor II G20210A and plasminogen activator inhibitor-1 4G/5G polymorphism. Despite similar criteria for inclusion of different studies in meta-analyses investigating first ischemic stroke in children, the obtained results were not consistent for all prothrombotic risk factors. The discrepancies found could be explained by methodological issues like different sample sizes, patient populations included and lack of controls. In order to provide the necessary power for randomized control trials, multi-center, multi-national approaches like International Pediatric Stroke Study have been initiated with the aim to describe risk factors for childhood stroke and explore their relationship with presentation, age, geography, and infarct characteristics. Although it is evident from numerous studies that the frequency of inherited prothrombotic factors is increased in pediatric stroke, single thrombophilia does not fully explain stroke in a child as it represents only a mild risk factor. Further studies are needed, as improved understanding of underlying mechanisms will improve primary and secondary prevention of childhood stroke.  相似文献   
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Objective  

Hemodilution changes the physical properties of blood by reducing its hematocrit and blood viscosity. We tested whether prolonged hypervolemic hemodilution (HHD) impairs functional capillary density (FCD) of ileal mucosa in healthy mechanically-ventilated pigs and if there is any correlation between changes in FCD of ileal and sublingual mucosas during HHD.  相似文献   
28.
Effective teaching methods-- Project-based learning in physics   总被引:1,自引:0,他引:1  
The paper presents results of the research of new effective teaching methods in physics and science. It is found out that it is necessary to educate pre-service teachers in approaches stressing the importance of the own activity of students, in competences how to create an interdisciplinary project. Project-based physics teaching and learning seems to be one of the most effective methods for teaching science for understanding. It is necessary to provide in-service teachers instruction (seminars) and prepare sample projects with proposals how to develop, run and evaluate interdisciplinary projects. Projects are important "real-world" physics modules, modern physics and everyday life problems can be integrated into the high school curriculum. Examples of projects that were worked out are presented.  相似文献   
29.
The author discusses the digitization of the archival collection of the Polish Institute of Arts and Sciences of America (PIASA), the long-term planning of this project, financial support, collaboration with Polish institutions, and several selected collections. Digitized archival documents are available on the PIASA website and are included in the database of the National Archives of Poland.  相似文献   
30.
This paper uses a range of case studies from contemporary art and indigenous collections to explore synergies between the disciplines and pose questions about contemporary perceptions of condition and durability. The idea that value is only connected to original material or specific perceptions of condition has been challenged repeatedly by the very makers and primary users of these collections. Nevertheless, old expectations in relation to collections may still affect conservation processes. The conservator is positioned at the center of these tensions, trying to understand, negotiate and mediate the interests and values of dynamic layers of significance associated with the object being treated. Attempting to homogenize or generalize these relationships would directly affect the complexity of the meanings of the artworks and run the risk of hollowing them.  相似文献   
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