A Study of Students' Learning Styles, Discipline Attitudes and Knowledge Acquisition in Technology-Enhanced Probability and Statistics Education

Many modern technological advances have direct impact on the format, style and efficacy of delivery and consumption of educational content. For example, various novel communication and information technology tools and resources enable efficient, timely, interactive and graphical demonstrations of diverse scientific concepts. In this manuscript, we report on a meta-study of 3 controlled experiments of using the Statistics Online Computational Resources in probability and statistics courses. Web-accessible SOCR applets, demonstrations, simulations and virtual experiments were used in different courses as treatment and compared to matched control classes utilizing traditional pedagogical approaches. Qualitative and quantitative data we collected for all courses included Felder-Silverman-Soloman index of learning styles, background assessment, pre and post surveys of attitude towards the subject, end-point satisfaction survey, and varieties of quiz, laboratory and test scores. Our findings indicate that students' learning styles and attitudes towards a discipline may be important confounds of their final quantitative performance. The observed positive effects of integrating information technology with established pedagogical techniques may be valid across disciplines within the broader spectrum courses in the science education curriculum. The two critical components of improving science education via blended instruction include instructor training, and development of appropriate activities, simulations and interactive resources.

SOCR Motion Charts: An Efficient, Open-Source, Interactive and Dynamic Applet for Visualizing Longitudinal Multivariate Data

The amount, complexity and provenance of data have dramatically increased in the past five years. Visualization of observed and simulated data is a critical component of any social, environmental, biomedical or scientific quest. Dynamic, exploratory and interactive visualization of multivariate data, without preprocessing by dimensionality reduction, remains a nearly insurmountable challenge. The Statistics Online Computational Resource (www.SOCR.ucla.edu) provides portable online aids for probability and statistics education, technology-based instruction and statistical computing. We have developed a new Java-based infrastructure, SOCR Motion Charts, for discovery-based exploratory analysis of multivariate data. This interactive data visualization tool enables the visualization of high-dimensional longitudinal data. SOCR Motion Charts allows mapping of ordinal, nominal and quantitative variables onto time, 2D axes, size, colors, glyphs and appearance characteristics, which facilitates the interactive display of multidimensional data. We validated this new visualization paradigm using several publicly available multivariate datasets including Ice-Thickness, Housing Prices, Consumer Price Index, and California Ozone Data. SOCR Motion Charts is designed using object-oriented programming, implemented as a Java Web-applet and is available to the entire community on the web at www.socr.ucla.edu/SOCR_MotionCharts. It can be used as an instructional tool for rendering and interrogating high-dimensional data in the classroom, as well as a research tool for exploratory data analysis.

Five-year outcomes of laparoscopic adjustable gastric banding and laparoscopic Roux-en-Y gastric bypass in a comprehensive bariatric surgery program in Canada

BACKGROUND

Bariatric surgery remains the most effective modality to induce sustainable weight loss in the morbidly obese. Our aim was to compare outcomes between the laparoscopic Roux-en-Y gastric bypass (LRYGBP) and the laparoscopic adjustable gastric banding device (LAGBD) method with 5-year follow-up in a Canadian bariatric surgery centre.

METHODS

This is a retrospective outcomes analysis of 1035 laparoscopic bariatric procedures performed over 7 years. We extracted data from our prospectively collected bariatric surgery registry from Feb. 1, 2002, to Jun. 30, 2008. We evaluated patient demographics, weight loss, complications, mortality and need for revision surgery by procedure type.

RESULTS

We examined outcomes in 149 (14.4%) LAGBD and 886 (85.6%) LRYGBP procedures. The mean body mass index (BMI) was significantly higher in the LRYGBP group (50.9, standard deviation [SD] 8.9, v. 45.0, SD 6.7) whereas age and sex ratio were the same. There were 3 deaths (0.3%) in the LRYGBP group and no deaths in the LAGBD group. Sixteen patients (10.8%) in the LAGBD group needed conversion to LRYGBP because of poor weight loss, band intolerance, band erosion or slippage, and 6 patients (0.7%) in the LRYGBP group required revision because of inability to achieve the desired weight loss. The percent excess-weight loss was 41, 49, 59, 60 and 61 at 1, 2, 3, 4 and 5 years postsurgery for the LAGBD patients who kept their band, and 70, 79, 79, 79 and 75 for the LRYGBP patients.

CONCLUSION

Laparoscopic weight loss surgery can be performed safely with acceptable mortality. Our study suggests superior weight loss and low revision requirement for the LRYGBP, making this a more durable procedure in a publicly funded health care system.

Statistics Online Computational Resource for Education

The Statistics Online Computational Resource (www.SOCR.ucla.edu) provides one of the largest collections of free Internet-based resources for probability and statistics education. SOCR develops, validates and disseminates two core types of materials - instructional resources and computational libraries.

Law of Large Numbers: the Theory, Applications and Technology-based Education

Modern approaches for technology-based blended education utilize a variety of recently developed novel pedagogical, computational and network resources. Such attempts employ technology to deliver integrated, dynamically-linked, interactive-content and heterogeneous learning environments, which may improve student comprehension and information retention. In this paper, we describe one such innovative effort of using technological tools to expose students in probability and statistics courses to the theory, practice and usability of the Law of Large Numbers (LLN). We base our approach on integrating pedagogical instruments with the computational libraries developed by the Statistics Online Computational Resource (www.SOCR.ucla.edu). To achieve this merger we designed a new interactive Java applet and a corresponding demonstration activity that illustrate the concept and the applications of the LLN. The LLN applet and activity have common goals - to provide graphical representation of the LLN principle, build lasting student intuition and present the common misconceptions about the law of large numbers. Both the SOCR LLN applet and activity are freely available online to the community to test, validate and extend (Applet: http://socr.ucla.edu/htmls/exp/Coin_Toss_LLN_Experiment.html, and Activity: http://wiki.stat.ucla.edu/socr/index.php/SOCR_EduMaterials_Activities_LLN).

Central Limit Theorem: New SOCR Applet and Demonstration Activity

Modern approaches for information technology based blended education utilize a variety of novel instructional, computational and network resources. Such attempts employ technology to deliver integrated, dynamically linked, interactive content and multifaceted learning environments, which may facilitate student comprehension and information retention. In this manuscript, we describe one such innovative effort of using technological tools for improving student motivation and learning of the theory, practice and usability of the Central Limit Theorem (CLT) in probability and statistics courses. Our approach is based on harnessing the computational libraries developed by the Statistics Online Computational Resource (SOCR) to design a new interactive Java applet and a corresponding demonstration activity that illustrate the meaning and the power of the CLT. The CLT applet and activity have clear common goals; to provide graphical representation of the CLT, to improve student intuition, and to empirically validate and establish the limits of the CLT. The SOCR CLT activity consists of four experiments that demonstrate the assumptions, meaning and implications of the CLT and ties these to specific hands-on simulations. We include a number of examples illustrating the theory and applications of the CLT. Both the SOCR CLT applet and activity are freely available online to the community to test, validate and extend (Applet: http://www.socr.ucla.edu/htmls/SOCR_Experiments.html and Activity: http://wiki.stat.ucla.edu/socr/index.php/SOCR_EduMaterials_Activities_GeneralCentralLimitTheorem).

Pedagogical Utilization and Assessment of the Statistic Online Computational Resource in Introductory Probability and Statistics Courses

Technology-based instruction represents a new recent pedagogical paradigm that is rooted in the realization that new generations are much more comfortable with, and excited about, new technologies. The rapid technological advancement over the past decade has fueled an enormous demand for the integration of modern networking, informational and computational tools with classical pedagogical instruments. Consequently, teaching with technology typically involves utilizing a variety of IT and multimedia resources for online learning, course management, electronic course materials, and novel tools of communication, engagement, experimental, critical thinking and assessment.The NSF-funded Statistics Online Computational Resource (SOCR) provides a number of interactive tools for enhancing instruction in various undergraduate and graduate courses in probability and statistics. These resources include online instructional materials, statistical calculators, interactive graphical user interfaces, computational and simulation applets, tools for data analysis and visualization. The tools provided as part of SOCR include conceptual simulations and statistical computing interfaces, which are designed to bridge between the introductory and the more advanced computational and applied probability and statistics courses. In this manuscript, we describe our designs for utilizing SOCR technology in instruction in a recent study. In addition, present the results of the effectiveness of using SOCR tools at two different course intensity levels on three outcome measures: exam scores, student satisfaction and choice of technology to complete assignments. Learning styles assessment was completed at baseline. We have used three very different designs for three different undergraduate classes. Each course included a treatment group, using the SOCR resources, and a control group, using classical instruction techniques. Our findings include marginal effects of the SOCR treatment per individual classes; however, pooling the results across all courses and sections, SOCR effects on the treatment groups were exceptionally robust and significant. Coupling these findings with a clear decrease in the variance of the quantitative examination measures in the treatment groups indicates that employing technology, like SOCR, in a sound pedagogical and scientific manner enhances overall the students' understanding and suggests better long-term knowledge retention.

Impact of bariatric surgery on cardiovascular and musculoskeletal morbidity

BACKGROUND

Obesity is currently recognized as a global epidemic. According to recent statistics, the prevalence of obesity increased from 13.8% of the Canadian population in 1978-1979 to 23.1% in 2004, and the prevalence of morbid obesity increased from .9% in 1978-1979 to 2.7% in 2004. Obesity is a known risk factor for highly prevalent chronic diseases, including cardiovascular and musculoskeletal disorders. The objective of the study was to assess the impact of bariatric surgery on cardiovascular and musculoskeletal morbidity.

METHODS

This was an observational study that compared a cohort of 1035 morbidly obese patients treated with bariatric surgery at the Centre for Bariatric Surgery, McGill University Health Centre with a matched cohort of 5746 morbidly obese nonsurgically treated controls. Data were obtained from the Quebec provincial health insurance database (Régie de l'Assurance Maladie du Québec). Morbidity indicators included diagnoses or treatment for cardiovascular or musculoskeletal disorders.

RESULTS

Patients who underwent bariatric surgery had a significant 62% mean reduction in excess weight and 32% mean reduction in body mass index (P < .001). Compared with the matched controls, patients who had undergone bariatric surgery had significantly lower rates of diagnoses and treatments related to cardiovascular and musculoskeletal conditions.

CONCLUSIONS

These results indicate that bariatric surgery is effective in reducing weight and significantly reduces the risk of cardiovascular and musculoskeletal morbidity.

Effect of laparoscopic versus open gastric bypass surgery on postoperative pain and bowel function

BACKGROUND

This study was designed to assess postoperative pain and bowel function in morbidly obese patients undergoing Roux-en-Y gastric bypass (RYGBP) performed either by open or laparoscopic technique.

METHODS

We prospectively studied patients scheduled for RYGBP between July 2002 and June 2003. Patients were assigned to the laparoscopic or open procedure by one surgeon. All patients received patient controlled analgesia (PCA) with intravenous morphine and rectal naproxen 500 mg every 12 hours. Postoperative analgesia was assessed daily using a visual analog scale (VAS) at rest, on walking and coughing. The amount of morphine used during the first 48 hours, the time of return of gastrointestinal motility and the time until first oral food intake were recorded.

RESULTS

53 patients were enrolled and studied (laparoscopic group n=33, open group n=20). Patients undergoing laparoscopic RYGBP requested less morphine (P=0.0001) and showed lower VAS pain scores than patients undergoing open RYGBP. The return of bowel movement in the laparoscopic group occurred 1 day earlier than in the open group (P=0.01). The time to first passage of gas (P=0.01) and oral food intake (P=0.06) was shorter after laparoscopic than after open RYGBP. Patients in the laparoscopic group were discharged 1(1/2) days earlier than patients in the open group (P=0.01).

CONCLUSION

The laparoscopic RYGBP operation was associated with less postoperative pain and morphine consumption than the open RYGBP, thereby facilitating an earlier recovery of intestinal motility.

Patient controlled i.v. analgesia is an acceptable pain management strategy in morbidly obese patients undergoing gastric bypass surgery. A retrospective comparison with epidural analgesia

PURPOSE

To examine the hypothesis that pain treatment with patient controlled analgesia (PCA) using iv morphine is a suitable and safe alternative to epidural analgesia in morbidly obese patients undergoing gastric bypass surgery. We retrospectively compared the postoperative periods in all patients undergoing this procedure in our institution between November 1999 and November 2001.

METHODS

According to their perioperative pain treatment, patients were assigned to a PCA group (with iv morphine) or an epidural analgesia group, in which patients received either intermittent doses of morphine or continuous infusions of bupivacaine/fentanyl. Study endpoints included quality of pain control, incidence of cardiovascular and respiratory complications, analgesia related side effects, time to ambulation and first flatus, length of hospital stay, and wound infections.

RESULTS

Data from 86 patients were analyzed with 40 patients in the PCA group and 46 patients in the epidural group. Groups were similar with respect to age, body mass index, and gender. The type of analgesia did not affect the quality of pain control at rest, the frequency of nausea and pruritus, the time to ambulation and return of gastrointestinal function, and the length of hospital stay. Patients receiving epidural analgesia had a greater risk of wound infection than subjects with PCA (epidural group: 39%, PCA group: 15%, P = 0.01).

CONCLUSION

We conclude that in grossly obese patients undergoing gastric bypass surgery PCA with iv morphine is an acceptable strategy for pain management and may confer some advantages when compared to epidural analgesia.

Clinafloxacin versus piperacillin-tazobactam in treatment of patients with severe skin and soft tissue infections

Patients (n = 409) with severe skin and soft tissue infections (SSTIs) were randomized to receive clinafloxacin or piperacillin-tazobactam (plus optional vancomycin for methicillin-resistant cocci), administered intravenously, with the option to switch to oral medication. Most patients had cellulitis, wound infections, or diabetic foot infections. Staphylococcus aureus, Enterococcus faecalis, and Pseudomonas aeruginosa were the most common baseline pathogens. Fewer baseline pathogens were resistant to clinafloxacin (1.8%) than to piperacillin-tazobactam (6.2%) (P = 0.001). The clinafloxacin and piperacillin-tazobactam groups did not differ significantly in clinical cure rates (68.8 and 65.2%, respectively) or microbiologic eradication rates (61.5 and 57.2%). Clinafloxacin yielded higher eradication rates for all three of the most common pathogenic species, although no differences were statistically significant. Within the power of this study, the overall frequency of adverse events was similar (P = 0.577) in the two treatment groups. Drug-associated adverse events (P = 0.050) and treatment discontinuations (P = 0.052) were marginally more frequent in the clinafloxacin group, primarily due to phototoxicity in outpatients receiving clinafloxacin. Although most cases of phototoxicity were mild to moderate, four cases were reported as severe. In summary, clinafloxacin monotherapy was equivalent in effectiveness to therapy with piperacillin-tazobactam plus optional vancomycin in the treatment of hospitalized patients with severe SSTIs.

Regional specificity of ASP binding in human adipose tissue

Obesity, in particular omental (OM) adiposity, is associated with diabetes and cardiovascular disease. Thus site-specific regulation of fat storage is important to understand. Acylation-stimulating protein (ASP) is a potent stimulator of glucose transport and triglyceride synthesis in adipocytes. In the present study, we characterized receptor binding of 125I-labeled ASP to human adipocyte plasma membranes from paired OM and subcutaneous (SC) sites in normal (N) and obese (O) male (M) and female (F) subjects (n = 24). Overall, specific binding of 125I-ASP was in the order of SC > OM and O > N (in SC tissue, particularly in F). Receptor affinity of 125I-ASP was higher [lower dissociation constant (Kd)] in SC than in OM (63.6 +/- 16.2 vs. 160.7 +/- 38.6 nM, P < 0.02), especially in F (37.0 +/- 11.1 F-N and 26.3 +/- 6.7 nM F-O) and lower (higher Kd) in male OM (291.8 +/- 116.8 M-N and 149.4 +/- 56.4 M-O). The greater binding and higher affinity of 125I-ASP binding to SC suggests that ASP may be an important factor in maintaining regional adipose tissue mass. Conversely, lower binding and receptor affinity in male OM adipose tissue may contribute to the fatty acid imbalance and metabolic complications associated with this syndrome, by reducing the efficiency of adipose fatty acid trapping by the ASP pathway.

Bioavailability of oral ciprofloxacin in early postsurgical patients

OBJECTIVE

To evaluate the absorption of oral ciprofloxacin within 24 hours of laparotomy for major elective surgery or peritonitis.

DESIGN

In this prospective trial, patients were given a 750-mg oral close the morning after major elective surgery (n=15) or surgery for peritonitis (n=7). Healthy volunteers served as controls (n=9). Serial urine and blood samples were drawn during the subsequent 12 hours, and pharmacokinetic measures were determined by standard high-performance liquid chromatography assay procedures.

SETTING

Multicenter, university-affiliated hospitals.

MAIN OUTCOME MEASURES

Drug absorption as determined by area under the concentration time curve, maximum concentration, and time to maximum concentration.

RESULTS

Oral bioavailability was reduced in elective surgery and peritonitis patients compared with controls. Among the 15 elective surgery patients, 27% (4/15) showed no absorption. The remaining 73% (11/15) had an area under the curve comparable with that of controls (8.3+/-1.6 (mg/[L x h]). Among all patients, those who showed drug absorption vs those who showed no absorption did not differ with respect to malignant neoplasm, case type, age, or biochemistry. However, patients showing no absorption were significantly heavier than patients showing absorption (patients showing absorption, 15%+/-3% over ideal body weight vs patients showing no absorption, 29%+/-6% over ideal body weight; P<.05). When elective surgery patients were stratified by presence or absence of obesity (25% above ideal body weight), mean area under the curve in nonobese patients was 9.80+/-2.37 vs 0.91+/-0.56 (mg/(L x h) in obese patients (P<.05).

CONCLUSIONS

Oral bioavailability was reduced for peritonitis surgery patients on the first day postoperatively, and for obese elective surgery patients. To achieve adequate serum levels requires continuation of intravenous antibiotics in patients with peritonitis, and adjustment of oral dosage in obese patients in the early period after elective surgery.