The Effect of Feedback Types on Academic Achievement in Learning with Computerized Tests

An earlier version of this article was presented at the Pacific Rim Objective Measurement Symposium (PROMS 2006), The Hong Kong Institute of Education, Tai Po, Hong Kong, June 27th-29th, 2006The purpose of this study was to show the effect of back types (standardized type vs. differentiated type) on academic achievement in learning with computerized tests. For this study, two computerized learning programs with different feedback types were developed with HTML, PHP, and SQL computer languages, and a science achievement test was developed by two high school science teachers. The science achievement tests content and face validity were examined by 5 high school science teachers and its Cronbach's alpha coefficient was 0.82. The research subjects were 137 10th graders from 4 classrooms within 2 high schools in Korea. They were divided into two groups. One group took a 3-weeks learning program with computerized a test using standardized type feedbacks. The other group also took a 3-week learning program with a computerized test using differentiated type feedbacks. After learning with computerized tests was implemented, a science achievement test was administered to all students belonging to both groups. The result of data analysis with ANCOVA was that differentiated type feedback was more effective than the standardized type feedback for learning with computerized test (F=8.98, p<0.01)

Numerical study on desalinated water flux from NACL solution using hollow fiber type DCMD module

Paper presented at the 9th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Malta, 16-18 July, 2012.The direct contact membrane distillation process is used for water desalination. DCMD is a thermally driven separation process, in which only vapor molecules transfer through a microporous hydrophobic membrane. The driving force in the DCMD process is the vapor pressure difference induced by the temperature difference across the hydrophobic membrane. In this study, the one-dimensional based model is developed for predicting the performance of the seawater desalination to produce fresh water for hollow fiber type DCMD module. The mass, energy and momentum balance equations are coupled to determine the concentration of NaCl, the temperature and velocity distribution of the feed and permeate side along the module length, and productivity of fresh water in the DCMD process. The KMPT model is used to calculate the mass transfer at the membrane surface. The mathematical and kinetics models used in this study are validated in comparison of the present simulation results with previous data given in the literature. The simulation results are in good agreement with the data in the literature. The performance of pure water production rate with respect to the membrane distillation coefficient is compared with the previously reported data. The numerical analysis is performed on a DCMD module using hollow fiber type PVDF membrane with a pore size of 0.22 μm. Feed solutions are aqueous NaCl solution. The values of the parameters considered in this work are: feed temperature, 40-70 ; feed velocity, 0.472m/s to 0.55m/℃ s; mass fraction of salt, 0.025-0.05; cold permeate temperature, 17-45℃ and the velocity of the permeate side are 0.3 m/s. It is found that the production rate of fresh water increases with feed temperature and velocity, but decreases with feed concentration.dc201

Clinical Efficacy of Primary Tumor Volume Measurements: Comparison of Different Primary Sites

ObjectivesThe purpose of study was to determine the clinical efficacy of primary tumor volume measurements of different primary sites in the oropharynx compared to the oral cavity.MethodsA retrospective analysis of 85 patients with oral cavity or oropharynx cancer. The tumor area was manually outlined from axial magnetic resonance (MR) series. The software calculated the tumor volumes, automatically. The values of the primary tumor volumes were then subdivided into separate groups (≤3,500 mm3, >3,500 mm3).ResultsThe prognostic indicators were the cT and cN (oral cavity); age, primary site, cT, cN, and primary tumor volume (oropharynx) on the univariate analysis. There was no significant prognostic factor for oral cavity cancer on the multivariate analysis. Primary site, cN, and primary tumor volume were independent prognostic indicators for oropharynx cancer by multivariate analysis.ConclusionPrimary tumor volume measurement is a reliable way to stratify outcome, and make up for the weak points in the American Joint Committee on Cancer staging system with oropharynx cancer

Identification of replicative senescence-associated genes in human umbilical vein endothelial cells by an annealing control primer system

Cellular senescence is regulated by specific genes in many organisms. The identification and functional analysis of senescence-associated genes could provide valuable insights into the senescence process. Here, we employed a new and improved differential display reverse transcription-polymerase chain reaction (DDRT-PCR) method that involves annealing control primers (ACPs) to identify genes that are differentially expressed in human umbilical endothelial cells during replicative senescence. Using 120 ACPs, we identified 31 differentially expressed genes (DEGs). Basic local alignment search tool (BLAST) search revealed 29 known genes and two unknown genes. Expression levels of the 29 known genes were confirmed by real-time quantitative RT-RCR and by Western blotting for eight of these genes. CD9 antigen, MHC class I chain-related sequence A (MICA) and cell division cycle 37 homolog (CDC37) were up-regulated, and bone morphogenetic protein 4 (BMP4), dickkopf-1 (DKK1), and transcription factor 7-like 1 (TCF7L1) were down-regulated in old cells. Treatment with recombinant human MICA caused a decrease in cell proliferation and an increase in senescence-associated beta-galactosidase staining. Further analysis of differentially expressed genes may provide insights into the molecular basis of replicative senescence and vascular diseases associated with cellular senescence

The Benefits and Risks of Prophylactic Central Neck Dissection for Papillary Thyroid Carcinoma: Prospective Cohort Study

Objectives. This study evaluated the benefits of performing prophylactic central neck dissection (CND) with total thyroidectomy (TT) in management of papillary thyroid carcinoma (PTC) patients who were clinically node-negative at presentation. Methods. A total of 257 patients with stage T1 or T2 PTC and without preoperative evidence of lymph node involvement (N0) were enrolled in this prospective study. The patients were randomly assigned to two groups: (1) a total thyroidectomy (TT) group (n=104) or (2) a TT plus CND group (n=153). The two groups were compared for their perioperative data, complication rates, disease recurrence rates, and clinical outcomes. Results. The two groups of patients were similar in age, sex ratio, follow-up duration, and tumor size (P=0.227, 0.359, 0.214, and 0.878, resp.). The two groups showed similar rates of disease recurrence (3.9% in the TT group versus 3.3% in the TT plus CND group); however, complications occurred more frequently in the TT plus CND group; especially transient hypocalcemia (P=0.043). Conclusions. Patients treated with TT plus CND had a higher rate of complications with similar recurrence rate. We believe that CND may not be routinely recommended when treating patients with PTC