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AbstractThis paper is intended as an exploration of university faculty and students’ perceptions of a number of dimensions involved in the written composition of academic texts. We analysed the responses to scale 3 in the European Writing Survey (EUWRIT) (in its Spanish version: Encuesta Europea sobre la Escritura Académica, EEEA) by a group of social science and humanities students (n = 1,030) and faculty (n = 230) from nine Spanish universities. We then examined the similarities and differences in their perceptions and established a factorial structure of the different dimensions underlying the writing process. The data indicate that both groups concur in the value assigned to both changing ideas in the course of the composition process (although this process seems to be understood differently by each group) and the revision and feedback processes. The students, however, claim to be involved in more planning and previous reading activities than the teachers perceive them to be. The significance of these results for a process-oriented perspective in academic writing is discussed. 相似文献
53.
We consider the problem of controlling the model of one-dimensional fluid flow through a soil packed tube in which a contaminant is initially distributed. A fluid is pumped through a tube to remove the contaminant. The control problem is to determine the optimal convective velocity due to the fluid being pumped by minimizing a given performance criterion. The performance criterion is chosen to be a combination of the total contaminant at the final time and the cost of the control. The set of orthogonal Fourier trigonometry series is used as a basis function of the Galerkin procedure to lump the distributed parameter system. A Legendre wavelet operational matrix of derivative is used to approximate the control and modal state variables. The main characteristics of this technique is that it reduces these problems to those of solving a system of algebraic equations, thus greatly simplifying the problem. The effectiveness of the proposed approach is illustrated numerically and the results are quite satisfactory. 相似文献
54.
Rich Ling Johannes Bjelland Pål Roe Sundsøy Scott W. Campbell 《The Information Society》2014,30(4):282-291
This article examines how we use mobile telephony to maintain our physically and socially closest social circle. The analysis is based on traffic data gathered from Norway using approximately 24 million calls and texts made by private individuals. Previous research has shown that our temporal and spatial movement is highly predictable and that the majority of calls and text messages are sent to only four to six different persons. This article extends this research by examining both tie strength and the distance between the interlocutors in urban and rural settings. The findings show that even as information and communication technologies (ICTs) potentially put the world at our fingertips, the mobile phone is an instrument of a more limited geographical and social sphere. Approximately two-thirds of our calls/texts go to strong ties that are within a 25-km radius. 相似文献
55.
Silvia Izquierdo álvarez Eva Barrio Ollero Francisco Miguel Llinares Sanjuan Fabiola Lorente Martínez María Teresa Calvo Martín 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):159-166
Introduction:
Additional nucleotide substitutions in the 3′-untranslated region of prothrombin gene could explain some thrombotic events and also adverse pregnancy outcomes. We describe the first case of a homozygous 20209C>T mutation as the cause of deep vein thrombosis in a Spanish patient.Case and methods:
The 56-year-old male patient with a partial tear of the Achilles tendon developed calf (tibial) deep vein thrombosis after immobilization and was treated with an anticoagulant. To determine if the deep vein thrombosis was of genetic origin, a peripheral blood DNA sample was analysed for the presence of the three most frequent mutations associated with thrombotic events: factor V Leiden (1691G>A), prothrombin (20210G>A) and methylene tetrahydrofolate reductase (677C>T). The presence or absence of the normal allele of prothrombin could not be determined using the PTH-FV-MTHFR StripAssay (Vienna Lab).Results:
Comprehensive analysis showed that the patient had a variant interfering with the polymerase chain reaction product, we sequenced the entire prothrombin gene and found that the patient had a homozygous C>T mutation at position 20209; this interfered with the polymerase chain reaction product, which needs a C at this position to be able to bind to the wild-type probe present in the test strip.Conclusion:
The homozygous 20209C>T mutation and the presence of the mutation 677C>T in heterozygosity explained the patient’s deep vein thrombosis because the combination of mutations would increase the risk of thrombosis. Suitable genetic counselling should be provided to the patient and first-degree relatives as it important to detect prothrombin gene variants that could increase risk for thrombotic events. 相似文献56.
Meltem Kilercik Abdurrahman Coskun Mustafa Serteser Deniz Inan Ibrahim Unsal 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):138-145
Background:
The ultra-large von Willebrand factor (vWF) multimers are very active and must be degraded by ADAMTS13 for optimal activity. A severe functional deficiency of ADAMTS13 has been associated with thrombotic thrombocytopenic purpura. The correct interpretation of patient vWF and ADAMTS13 plasma levels requires an understanding of the biological variation associated with these analytes. In the present paper, we aimed to determine the biological variation of ADAMTS13 and vWF in human adults.Materials and methods:
Blood samples were collected weekly from 19 healthy subjects for 5 consecutive weeks. vWF activity and antigenicity were determined using aggregometric and immunoturbidimetric methods. ADAMTS13 antigenicity and activity were determined by ELISA.Results:
The within-subject biological variations for vWF activity and antigenicity were 8.06% and 14.37%, respectively, while the between-subject biological variations were 18.5% and 22.59%, respectively. The index of individuality for vWF activity was 0.44, while vWF antigenicity was 0.64. Similarly, ADAMTS13 activity and antigenicity within-subject biological variations were 12.73% and 9.75%, respectively, while between-subject biological variations were 9.63% and 6.28%, respectively. The ADAMTS13 indexes of individuality were 1.32 and 1.55, respectively.Conclusion:
We report high biological variation and individuality in vWF antigenicity and activity levels. However, ADAMTS13 antigenicity and activity displayed high biological variation, but low individuality. Thus, population-based reference intervals may be useful for monitoring ADAMTS13 antigenicity and activity, but not for vWF, which displays high individuality. These findings should be considered when determining the reference interval and other clinical variables associated with ADAMTS13 and vWF levels. 相似文献57.
58.
59.
Building on common assumptions in theories of interest and mathematics education, this experimental study examined the effect of context personalization based on individual preferences, group personalization, and example choice with preselected popular examples on middle school students' situational interest and performance in mathematics. Participants (N = 713) learned a principle in probability calculus in one of four instructional conditions. Individual interest and perceived competence were examined as moderators on triggered and maintained situational interest, perceived value, task effort, and performance. Results showed that example choice triggered situational interest in the learning activity and that context personalization influenced perceived value and effort, contingent on students' perceived competence and individual interest in mathematics. We discuss results in relation to previous findings on interest-based interventions and the theoretical and practical implications. 相似文献
60.
Macarena Sánchez-Izquierdo Alonso María Prieto Ursúa José M Caperos 《Educational gerontology》2017,43(12):650-661
The objective of this study was to assess the relationship between the institutionalization of a dependent elderly relative and the family caregiver’s mental health, quality of life and caregiving satisfaction. We present data from 140 family caregivers caring for elderly family members, of whom 77 continued to live with family members and 63 had been institutionalized. We evaluated the factors influencing the decision to institutionalize the dependent relative, the effect of institutionalization on the caregiver’s psychological well-being and quality of life and the impact of strategies to find the meaning and cope with the relative’s placement on the caregiver’s emotional health and quality of life. Care does not end after institutionalization, but the stressors the caregiver faces change. Our results suggest that finding meaning increases satisfaction and reduces feelings of overload. They show that after institutionalization, stressors affecting caregivers are partly relieved, and that finding meaning increases the caregiver’s satisfaction, while decreasing the degree of overload. Our data, further, indicates that a good relationship and cooperation between the staff of the institution and the family are important to improve the caregivers’ emotional health and quality of life, and consequently, the quality of life of the dependent elderly relative. 相似文献