Development of a scale of Sense of Community in university online courses     

Giulia Balboni  Vittore Perrucci  Stefano Cacciamani  Bruno D. Zumbo 《Distance Education》2018,39(3):317-333

Creating a sense of community in online classes contributes to student retention and to their overall satisfaction with the course itself. This study aimed to develop a scale of sense of community of students attending online university courses. A series of ordinal exploratory factor analyses were conducted on data obtained from 839 students enrolled in Italian universities. Using an item analysis method, we were able to select the 36 most valid items from an original set of 60 items we had previously defined. These items are distributed across three related factors measuring membership, influence, and fulfillment of needs. This factorial structure replicates the McMillan and Chavis’s model of sense of community, upon the basis of which this scale was developed. The three factors presented good ordinal alpha and adequate convergent/divergent validity coefficients. The scale represents an efficient tool for the design, monitoring, and evaluation of online courses.  相似文献   

Computers With Wings: Flight Simulation and Personalized Landscapes     

Stefano?OssEmail author 《Journal of Science Education and Technology》2005,14(1):117-122

We propose, as a special way to explore the physics of flying objects, to use a flight simulator with a personalized scenery to reproduce the territory where students live. This approach increases the participation and attention of students to physics classes but also creates several opportunities for addressing side activities and arguments of various nature, from history to geography, computer science, and much more.  相似文献   

Challenges and prospects for Indian education in Mexico     

Stefano Varese 《Prospects》1990,20(3):345-355

Author of several books and articles on the ethnic question in Peru and Mexico, and on indigenous education.  相似文献   

Climate and litter C/N ratio constrain soil organic carbon accumulation     

Guoyi Zhou  Shan Xu  Philippe Ciais  Stefano Manzoni  Jingyun Fang  Guirui Yu  Xuli Tang  Ping Zhou  Wantong Wang  Junhua Yan  Gengxu Wang  Keping Ma  Shenggong Li  Sheng Du  Shijie Han  Youxin Ma  Deqiang Zhang  Juxiu Liu  Shizhong Liu  Guowei Chu  Qianmei Zhang  Yuelin Li  Wenjuan Huang  Hai Ren  Xiankai Lu  Xiuzhi Chen 《国家科学评论(英文版)》2019,6(4):746

Soil organic carbon (SOC) plays critical roles in stabilizing atmospheric CO₂ concentration, but the mechanistic controls on the amount and distribution of SOC on global scales are not well understood. In turn, this has hampered the ability to model global C budgets and to find measures to mitigate climate change. Here, based on the data from a large field survey campaign with 2600 plots across China''s forest ecosystems and a global collection of published data from forested land, we find that a low litter carbon-to-nitrogen ratio (C/N) and high wetness index (P/PET, precipitation-to-potential-evapotranspiration ratio) are the two factors that promote SOC accumulation, with only minor contributions of litter quantity and soil texture. The field survey data demonstrated that high plant diversity decreased litter C/N and thus indirectly promoted SOC accumulation by increasing the litter quality. We conclude that any changes in plant-community composition, plant-species richness and environmental factors that can reduce the litter C/N ratio, or climatic changes that increase wetness index, may promote SOC accumulation. The study provides a guideline for modeling the carbon cycle of various ecosystem scales and formulates the principle for land-based actions for mitigating the rising atmospheric CO₂ concentration.  相似文献   

Emotional Intensity-based Success Prediction Model for Crowdfunded Campaigns     

Stefano Faralli  Steve Rittinghaus  Nima Samsami  Damiano Distante  Eugénio Rocha 《Information processing & management》2021,58(1):102394

  相似文献   

The effects of two different correction strategies on the snatch technique in weightlifting     

Chiara Milanese  Valentina Cavedon  Stefano Corte  Tiziano Agostini 《Journal of sports sciences》2017,35(5):476-483

Improving motor skills represents one of the major issues in motor control and motor learning literature. The aim of this study was to investigate which of two strategies, method of amplification of error (MAE) or direct instruction (DI), would be more beneficial for error correction of the snatch technique. Thirty well-trained male weightlifters were randomly assigned to one of three training conditions (MAE, DI and Control). The experiment took place in only one practice session in which each lifter performed 3 pretraining trials, 8 training intervention trials, and 3 post-training trials, and a retention test session after 1 week. An optoelectronic motion capture system was used to measure the kinematic parameters of the weightlifting performance. After the training intervention, data showed that the MAE group revealed a greater improvement in several kinematic parameters when compared to the DI and Control groups, and the benefits derived from its application were still present 1 week later in the retention test. Nevertheless, the findings of the present study should be interpreted with caution due to the relatively small sample size; further research will also be necessary to evaluate the effects of MAE with different ability levels and other sport skills. The present findings could have practical implications for sport psychology and physical education because while practice is obviously necessary for improving learning, the efficacy of the learning process is essential in enhancing learners’ motivation and sport enjoyment.  相似文献   

A microfluidics assisted porous silicon array for optical label-free biochemical sensing     

Rea I  Orabona E  Lamberti A  Rendina I  De Stefano L 《Biomicrofluidics》2011,5(3):34120-3412010

A porous silicon (PSi) based microarray has been integrated with a microfluidic system, as a proof of concept device for the optical monitoring of selective label-free DNA-DNA interaction. A 4 × 4 square matrix of PSi one dimensional photonic crystals, each one of 200 μm diameter and spaced by 600 μm, has been sealed by a polydimethylsiloxane (PDMS) channels circuit. The PSi optical microarray elements have been functionalized by DNA single strands after sealing: the microfluidic circuit allows to reduce significantly the biologicals and chemicals consumption, and also the incubation time with respect to a not integrated device. Theoretical calculations, based on finite element method, taking into account molecular interactions, are in good agreement with the experimental results, and the developed numerical model can be used for device optimization. The functionalization process and the interaction between DNA probe and target has been monitored by spectroscopic reflectometry for each PSi element in the microchannels.  相似文献   

Racial Microaggressions: a Primer with Implications for Counseling Practice     

Sara Houshmand  Lisa B. Spanierman  Jack De Stefano 《International journal for the advancement of counseling》2017,39(3):203-216

Given their societal toll and ubiquitous nature, counselors and other mental health professionals inevitably will encounter clients who have experienced racial microaggressions in their practice. In this primer, we examine key issues relative to racial microaggressions and their impact on the lives of members of racial and ethnic minority groups. Drawing on burgeoning research, we also address likely coping strategies. Finally, we offer implications for mental health training and counseling practice. Throughout, we highlight the evident resilience of racial and ethnic minority individuals in the context of racial microaggressions.  相似文献   

Validity of criteria-based content analysis (CBCA) at trial in free-narrative interviews     

Roma P  Martini PS  Sabatello U  Tatarelli R  Ferracuti S 《Child abuse & neglect》2011,35(8):613-620

Objective

The reliability of child witness testimony in sexual abuse cases is often controversial, and few tools are available. Criteria-Based Content Analysis (CBCA) is a widely used instrument for evaluating psychological credibility in cases of suspected child sexual abuse. Only few studies have evaluated CBCA scores in children suspected of being sexually abused. We designed this study to investigate the reliability of CBCA in discriminating allegations of child sexual abuse during court hearings, by comparing CBCA results with the court's final, unappealable sentence. We then investigated whether CBCA scores correlated with age, and whether some criteria were better than others in distinguishing cases of confirmed and unconfirmed abuse.

Methods

From a pool of 487 child sexual abuse cases, confirmed and unconfirmed cases were selected using various criteria including child IQ ≥ 70, agreement between the final trial outcome and the opinion of 3 experts, presence of at least 1 independent validating informative component in cases of confirmed abuse, and absence of suggestive questions during the child's testimonies. This screening yielded a study sample of 60 confirmed and 49 unconfirmed cases. The 14 item version of CBCA was applied to child witness testimony by 2 expert raters.

Results

Of the 14 criteria tested, 12 achieved satisfactory inter-rater agreement (Maxwell's Random Error). Analyses of covariance, with case group (confirmed vs. unconfirmed) and gender as independent variables and age as a covariate, showed no main effect of gender. Analyses of the interaction showed that the simple effects of abuse were significant in both sex. Nine CBCA criteria were satisfied more often among confirmed than unconfirmed cases; seven criteria increased with age.

Conclusion

CBCA scores distinguish between confirmed and unconfirmed cases. The criteria that distinguish best between the 2 groups are Quantity of Details, Interactions, and Subjective Experience. CBCA scores correlate positively with age, and independently from abuse; all the criteria test except 2 (Unusual Details and Misunderstood Details) increase with age. The agreement rate could be increased by merging criteria Unusual and Superfluous details that achieve a low inter-rater agreement when investigated separately.

Practice implication

Given its ability to distinguish between confirmed and unconfirmed cases of suspected child abuse, the CBCA could be a useful tool for expert opinion. Because our strict selection criteria make it difficult to generalize our results, further studies should investigate whether the CBCA is equally useful in the cases we excluded from our study (for example mental retardation).  相似文献   

Mineralogical-chemical Alteration and Origin of Ignimbritic Stones Used in the Old Cathedral of Nostra Signora di Castro (Sardinia,Italy)     

Stefano Columbu  Anna Gioncada  Marco Lezzerini  Fabio Sitzia 《文物保护研究》2013,58(7):397-422

ABSTRACT

The pyroclastic rocks belonging to the Late Eocene-Miocene volcanic activity that occurred in Sardinia between 38 and 15 Ma ago were widely used as construction materials in several Romanesque churches of the easternmost Logudoro area, as well as in large parts of the Sardinia territory. In this work, the ancient Cathedral of Nostra Signora di Castro (twelfth century) was taken as a representative case study. There is no historical or archaeological evidence of ancient quarries. Based on the geochemical, petrographic, and volcanological data on several samples from an extensive field area (approximately 150?km²), a geographical zoning of the volcanics has been recognised. In the Oschiri sector, there are three different sub-zones, which can be identified with different volcanic rocks: less fractionated rocks (Differentation Index ～70–78); intermediately fractionated rocks (D.I. ～76–79); and more fractionated rocks (D.I. ～77–82). To identify the origin of the ignimbrite rocks of the Church of Nostra Signora di Castro, two statistical methods were used: stepwise linear discriminant and canonical analysis. Moreover, to define the geochemical transformation processes induced by the alteration, a comparative study of concentrations of major and trace elements measured by XRF and SEM-EDX analyses on the surface portion and the innermost areas of the stone was made.  相似文献