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121.
122.
The aim of this investigation was to compare two differently designed e-assessments (formative assessments) which supported the same engineering courses for two academic years. In this investigation two group of students participated (Control Group: CG and Experimental Group: EG). The teachers followed exactly the same teaching approach using the same learning tools (apart from the e-assessments) in the same learning environment. The first group of students (CG) had the opportunity to timely receive grades along with the correct answers, when they submitted the e-assessments on-line. The teachers themselves designed these e-assessments in BlackBoard Vista© learning environment. The second group of students (EG) had the opportunity to receive feedback each on their own individual responses having unlimited attempts to participate in the e-assessments designed by PhD students. We will demonstrate that the addition of individual feedback and the unlimited attempts increased the EG group performance at the end of the courses (summative assessment) in comparison to the CG group of students. 相似文献
123.
Web-scale discovery services (WSDs) are a widespread phenomenon sweeping university libraries across the world. In this article the authors discuss this trend and their experience working on a test server with the open source discovery layer VuFind. Developed by Demian Katz of Villanova University, VuFind’s potential to index not only the library’s catalog but also proprietary databases through the integration of application program interfaces (APIs) offers public libraries the opportunity to develop a seamless website-to-catalog experience, thereby building a true virtual branch for their patrons. 相似文献
124.
Monica Favaro Pietro A. Vigato Alessia Andreotti Maria Perla Colombini 《Journal of Cultural Heritage》2005,6(4):295-305
The oil painting “La Medusa” executed by Caravaggio at the end of the XVI century on a wooden shield, was investigated by integrated physical–chemical and analytical methodologies in order to obtain scientific data capable of elucidating the state of conservation and the painting technique. Optical (OM) and electronic (SEM-EDS) microscopy, micro-FT-IR spectroscopy, gas chromatography–mass spectrometry (GC–MS) and pyrolysis GC–MS were applied on two microfragments and some organic samples obtained by solvent extraction using the swab cleaning technique. The obtained results indicated that Caravaggio probably reused an old shield as a previous gypsum preparation layer has been detected under the original painting layers. He used white lead, natural earths, verdigris and lead–tin yellow type I mixed with drying oils to paint. The considerable amount of amorphous particles of copper chlorides found in the green pigment verdigris suggests that it could have been produced according to the ancient recipe of verde salsum described by Theophilus. Mordant gilding has been identified on the upper part of the shield that can be related to an abandoned experiment to give the painting a mirror-like reflecting effect. Three different varnishes layers have been detected above the painted surface. The original and restoration varnishes have been identified and they contain a mixture of drying oil, mastic and turpentine and some beeswax. Cleaning tests, performed with different organic solvents, suggest the use of isopropyl alcohol as cleaning agent because it is less efficient in comparison to others solvents; thus it ensures a careful and controlled removal of the varnishes. 相似文献
125.
European Journal of Psychology of Education - The paper discusses the importance of incorporating naturalistic data from spontaneous written texts in language acquisition research in general, and... 相似文献
126.
This study investigated the effect of a single session of resistance exercise on postprandial lipaemia. Eleven healthy normolipidaemic men with a mean age of 23 (standard error = 1.4) years performed two trials at least 1 week apart in a counterbalanced randomized design. In each trial, participants consumed a test meal (1.2 g fat, 1.1 g carbohydrate, 0.2 g protein and 68 kJ x kg(-1) body mass) between 08.00 and 09.00 h following a 12 h fast. The afternoon before one trial, the participants performed an 88 min bout of resistance exercise. Before the other trial, the participants were inactive (control trial). Resistance exercise was performed using free weights and included four sets of 10 repetitions of each of 11 exercises. Sets were performed at 80% of 10-repetition maximum with a 2 min work and rest interval. Venous blood samples were obtained in the fasted state and at intervals for 6 h postprandially. Fasting plasma triacylglycerol (TAG) concentration did not differ significantly between control (1.03 +/- 0.13 mmol x l(-1)) and exercise (0.94 +/- 0.09 mmol x l(-1)) trials (mean +/- standard error). Similarly, the 6 h total area under the plasma TAG concentration versus time curve did not differ significantly between the control (9.84 +/- 1.40 mmol l(-1) x 6 h(-1)) and exercise (9.38 +/- 1.12 mmol x l(-1) x 6 h(-1)) trials. These findings suggest that a single session of resistance exercise does not reduce postprandial lipaemia. 相似文献
127.
M Martín-Matillas FB Ortega JR Ruiz D Martínez-Gómez G Vicente-Rodríguez A Marcos L Béghin A Kafatos M González-Gross M Zaccaria D Molnár S De Henauw M Sjöström LA Moreno MJ Castillo On Behalf Of The Helena Study 《Journal of sports sciences》2012,30(13):1329-1335
Abstract High physical fitness in childhood and adolescence is positively associated with favourable health-related outcomes. Our aim was to examine the relationship between relatives' (father, mother, brother, sister, and best friend) physical activity engagement and encouragement on adolescents' physical fitness. Adolescents were part of the HELENA study, a multi-centre study conducted in 10 cities from nine European countries in 2006-2008. Participants were 3288 adolescents (48% boys, 52% girls) aged 12.5-17.5 years with valid data on at least one of the three fitness variables studied: muscular strength (standing long jump), speed/agility (4×10 m shuttle run), and cardiorespiratory fitness (20 m shuttle run). The adolescents reported their relatives' physical activity engagement and encouragement. Analysis of covariance showed that relatives' physical activity engagement (father, mother, brother, and best friend) was positively related to cardiorespiratory fitness (P?0.05); and mother's and sisters' physical activity engagement were positively associated with higher muscular strength in adolescents (P?0.05). Furthermore, father's physical activity encouragement was positively linked to physical fitness (all fitness components) in adolescents (P?0.05). Interventions aimed at improving physical fitness in young people might be more successful when family members, particularly mothers and fathers, are encouraged to engage in physical activity and support adolescents' physical activity. 相似文献
128.
This paper investigates the determinants of R&D expenditure using a sample of UK listed companies with the highest spend from 2000 to 2005. We investigate the effect of corporate governance and ownership on R&D, using panel data. The results provide some evidence that more governance tends to depress R&D activity, a finding that is robust to whether a composite or disaggregated index of governance is used. One innovation of the paper is that we treat agency and finance effects interactively. The ownership stake of the CEO appears to be supportive for R&D. 相似文献
129.
Pau M Loi A Pezzotta MC 《Sports biomechanics / International Society of Biomechanics in Sports》2012,11(1):97-107
The aim of this investigation is to assess the effectiveness of a 6-week balance training (BT) protocol, integrated in regular training sessions, on postural sway of young female volleyball players (n = 26, age 13.0 +/- 0.2 years) divided into two groups (intervention and control; 13 per group). Trials were performed for bipedal and unipedal stance conditions before and after the BT protocol, using a pressure platform to collect center-of-pressure (COP) time series that were processed to calculate sway area, COP path length, and maximum displacement range in anteroposterior and mediolateral directions. The intervention group exhibited smaller sway areas in eyes closed conditions (intervention = 42.76 mm2, control = 67.60 mm2; p < 0.05) and Romberg quotients (intervention = 1.11 mm, control = 1.82 mm) in bipedal stance, while all the other parameters were unaffected. BT also reduced sway area (intervention = 122.70 mm2, control = 187.18 mm2) and anteroposterior COP displacements (intervention = 20.18 mm, control = 22.38 mm) of the non-dominant limb for single-leg stance. No significant change was found for the dominant limb. Although it is possible to hypothesize a beneficial effect of BT on young athletes, further investigations are required to clarify its actual effect on balance performance with respect to normal volleyball training. 相似文献
130.
Kamilla B. Kalinina Ilaria Bonaduce Maria Perla Colombini Irina. S. Artemieva 《Journal of Cultural Heritage》2012,13(3):259-274
This paper presents the first extensive investigation of the composition of both the organic and inorganic media used by Lorenzo Lotto, one of the outstanding artists of the Italian Renaissance in the early 16th century. By investigating four paintings from The State Hermitage Museum collection (Saint-Petersburg, Russia), new insights into the artist's painting techniques were obtained, which contribute to our understanding of the transition from egg tempera to oil painting techniques that took place in Italian paintings between the 15th to the mid 16th century. Inorganic materials were determined using SEM-EDX and PLM, revealing information on the artist's palette. Of particular note was the powdered colourless glass found in the priming layer of the Madonna delle Grazie, which was most likely used as dryer. Organic materials were analysed in individual paint layers using GC-MS, and revealed a mature use of drying oils as paint binders, skilfully mixed with other organic materials and inorganic driers, to obtain the desired aesthetical and technical qualities of the paint. The study revealed that Lotto used the tempera grassa technique through most of his creative life. 相似文献