53 research outputs found
A scanning electron-microscope examination of the scolex of Houttuynia struthionis
A scanning electron-microscope examination of the scolex of Houttuynia struthionis, a cestode of ostriches,
was undertaken in order to study its surface structure. The scolex differs from those of other
subfamilies in the family Davaineidae in that it does not have scale-like spines covering the base of the
rostellum. Instead, the base is covered with small hooks resembling the larger rostellar hooks in shape.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi.
Adobe Acrobat X Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format
Content analysis: What are they talking about?
Quantitative content analysis is increasingly used to surpass surface level analyses in Computer-Supported Collaborative Learning (e.g., counting messages), but critical reflection on accepted practice has generally not been reported. A review of CSCL conference proceedings revealed a general vagueness in definitions of units of analysis. In general, arguments for choosing a unit were lacking and decisions made while developing the content analysis procedures were not made explicit. In this article, it will be illustrated that the currently accepted practices concerning the âunit of meaningâ are not generally applicable to quantitative content analysis of electronic communication. Such analysis is affected by âunit boundary overlapâ and contextual constraints having to do with the technology used. The analysis of e-mail communication required a different unit of analysis and segmentation procedure. This procedure proved to be reliable, and the subsequent coding of these units for quantitative analysis yielded satisfactory reliabilities. These findings have implications and recommendations for current content analysis practice in CSCL research
Adjuvant chemotherapy is superior to chemoradiation after D2 surgery for gastric cancer in the per-protocol analysis of the randomized CRITICS trial
Background: The Intergroup 0116 and the MAGIC trials changed clinical practice for resectable gastric cancer in the Western world. In these trials, overall survival improved with post-operative chemoradiotherapy (CRT) and perioperative chemotherapy (CT). Intention-to-treat analysis in the CRITICS trial of post-operative CT or post-operative CRT did not show a survival difference. The current study reports on the per-protocol (PP) analysis of the CRITICS trial.Patients and methods: The CRITICS trial was a randomized, controlled trial in which 788 patients with stage Ib-Iva resectable gastric or esophagogastric adenocarcinoma were included. Before start of preoperative CT, patients from the Netherlands, Sweden and Denmark were randomly assigned to receive post-operative CT or CRT. For the current analysis, only patients who started their allocated post-operative treatment were included. Since it is uncertain that the two treatment arms are balanced in such PP analysis, adjusted proportional hazards regression analysis and inverse probability weighted analysis were used to minimize the risk of selection bias and to estimate and compare overall and event-free survival.Results: Of the 788 patients, 478 started post-operative treatment according to protocol, 233 (59%) patients in the CT group and 245 (62%) patients in the CRT group. Patient and tumor characteristics between the groups before start of the post-operative treatment were not different. After a median follow-up of 6.7 years since the start of post-operative treatment, the 5-year overall survival was 57.9% (95% confidence interval: 51.4% to 64.3%) in the CT group versus 45.5% (95% confidence interval: 39.2% to 51.8%) in the CRT group (adjusted hazard ratio CRT versus CT: 1.62 (1.24-2.12), P = 0.0004). Inverse probability weighted analysis resulted in similar hazard ratios.Conclusion: After adjustment for all known confounding factors, the PP analysis of patients who started the allocated post-operative treatment in the CRITICS trial showed that the CT group had a significantly better 5-year overall survival than the CRT group (NCT00407186).Surgical oncolog
Diagnostic accuracy of non-specialist versus specialist health workers in diagnosing hearing loss and ear disease in Malawi.
OBJECTIVE: To determine whether a non-specialist health worker can accurately undertake audiometry and otoscopy, the essential clinical examinations in a survey of hearing loss, instead of a highly skilled specialist (i.e. ENT or audiologist). METHODS: A clinic-based diagnostic accuracy study was conducted in Malawi. Consecutively sampled participants â„ 18 years had their hearing tested using a validated tablet-based audiometer (hearTest) by an audiologist (gold standard), an audiology officer, a nurse and a community health worker (CHW). Otoscopy for diagnosis of ear pathologies was conducted by an ENT specialist (gold standard), an ENT clinical officer, a CHW, an ENT nurse and a general nurse. Sensitivity, specificity and kappa (Îș) were calculated. 80% sensitivity, 70% specificity and kappa of 0.6 were considered adequate. RESULTS: Six hundred and seventeen participants were included. High sensitivity (>90%) and specificity (>85%) in detecting bilateral hearing loss was obtained by all non-specialists. For otoscopy, sensitivity and specificity were >80% for all non-specialists in diagnosing any pathology except for the ENT nurse. Agreement in diagnoses for the ENT clinical officer was good (Îș = 0.7) in both ears. For other assessors, moderate agreement was found (Îș = 0.5). CONCLUSION: A non-specialist can be trained to accurately assess hearing using mobile-based audiometry. However, accurate diagnosis of ear conditions requires at least an ENT clinical officer (or equivalent). Conducting surveys of hearing loss with non-specialists could lower costs and increase data collection, particularly in low- and middle-income countries, where ENT specialists are scarce
Firm decisions and market responses: Three accounting essays
Firms operate in a complex economic environment where they interact with a broad base of stakeholders. Stakeholders are interested in the economic environment of the firm and its prospects to determine the value of their claims. For this valuation a wide range of information sources is used which per definition provide a depiction of the firm and its economic environment. As the stakeholders are important to the firm, managers have incentives to try to affect their assessment of the firm, by making opportunistic disclosure decisions. In three essays, I examine topics revolving around this notion. In the first essay I show that reporting regulation requires firms to recognize their development activities as an asset on the balance sheet, even though the firm is likely to have incentives to avoid recognition. In addition, I show in this essay that it is not straightforward that required capitalization is beneficial for the valuation of firms by their equity investors. In the second essay I examine securitization transactions by U.S. banks, where they provide an explicit guarantee. Due to the specific reporting regulation, it is possible that the securitized loan portfolios no longer have to be recognized on the balance sheet. This particular securitization is beneficial for banks as the explicit guarantee reduces uncertainty for the buying party, making the transaction more appealing during times of economic uncertainty. My results indicate that even during the recent widespread financial crisis, where arguably liquidity markets dried up, these securitization transactions can still be used by banks to enhance their liquidity. In the third essay I examine the valuation by different stakeholders. In this essay I argue that the value of the respective claims can be interpreted as a summary statistic of all information used by the respective stakeholder. Then I show that the valuation processes by different stakeholders, namely shareholders and CDS contract holders, differs based on observable firm characteristics. My results indicate that this difference in the valuation processes can be exploited using the trading strategy developed in this essay
- âŠ