Perceptions of Students in Different Phases of Medical Education of Educational Environment: Ankara University Faculty of Medicine

The present study was undertaken to identify the perceptions of students about their educational environment in a newly restructured curriculum. The Turkish version of the DREEM questionnaire (total score: 200) was used to diagnose the strengths and weaknesses of the curriculum which is known to be a major determinant of educational environment. Five hundred fifty three students (years 1, 3, 5) voluntarily replied to the questionnaire. The mean DREEM score was found to be 117.63 (58.8%). The mean scores for the whole DREEM questionnaire and the five essential domains were found to be significantly different in different phases of medical education. The scores were found to be highest (123.65) for year 3 students and lowest (109.39) for year 5 students. The results are the first data of a curriculum reform obtained from the students about the educational environment and give important feedback to curriculum planners and change managers of the faculty for necessary improvement

A model study of measurement intellectual capital in Turkey and an application

Bu çalışmada, ulusal endüstri içinde yer alan firmaların entelektüel sermayelerinin, kısaca  maddi olmayan varlıklarının ölçülmesi için bir model yaratılmıştır. Yaratılan bu modelde entelektüel sermaye insan sermayesi, örgüt sermayesi ve ilişki sermayesi ile tanımlanmıştır. Bu model yaklaşımı ile Türkiye’deki işletmelerin pazar/defter değeri oranları ile entelektüel sermayeleri arasındaki ilişki incelenmiştir. Araştırma yöntemi olarak Likert-tipi anket çalışması uygulanmıştır. Yapılan araştırma sonuçlarına göre, firmaların insan sermayesi ve ilişki sermayesi ile işletmelerin pazar değerleri arasında pozitif ve güçlü bir ilişki olduğu gösterilmiştir. İşletmenin örgüt sermayesi ile, işletmenin insan ve ilişki sermayesi arasında pozitif yönde, güçlü bir korelasyon olduğu da gösterilmiştir. Anahtar Kelimeler: Entelektüel sermaye, maddi olmayan varlıklar, bilgi varlığının değerlendirilmesi.The purpose of this study is to define the elements of intellectual capital of firms in Turkey and to empirically investigate the relationship between intellectual capital and market value of firms in Istanbul Stock Exchange. For the research an intellectual capital measurement model is created and four hypothesis are defined: Hypothesis (1): There will be a positive relationship between the human capital and the market/book value. Hypothesis (2): There will be a positive relationship between the relation capital and the market/book value. Hypothesis (3a): There will be a positive relationship between the human capital and structural capital. Hypothesis (3b): There will be a positive relationship between the relation capital and structural capital. For testing the hypothesis two different survey studies have been done. In the pre-survey a questionnaire about 71 items, in the main survey about 21 items were designed. In designing of both questionnaire a 7-point Likert scale was used. For the result the statistical tests, Cronbach?s alpha test for reliability, principal components analysis, linear regression and partial least squares were executed. The main conclusions from this study are that: human capital and relation capital have a positive relationship with market/book value of firms in Turkey; and structural capital has a correlation with human and relation capital. Keywords: Intellectual capital, intangible assets, assessing knowledge assets

Subjective sleep and overall survival in chemotherapy-naïve patients with metastatic colorectal cancer

Backround: Sleep disorders are prevalent in patients with advanced cancer. Their impact on clinical outcomes is not well understood. Methods: A post-hoc analysis was conducted in 361 chemo-naïve patients with metastatic colorectal cancer completing twice the EORTC QLQ-C30 questionnaire within a randomized international phase III trial. The study assessed the effect on overall survival (OS) of subjective sleep complaint, used as a normal or a time-dependent covariate (TDC), using a multivariate Cox proportional hazard model. Prognostic analysis was conducted on the whole study population and separately in each treatment arm (conventional FOLFOX2, or chronomodulated chronoFLO4). Results: Sleep problems were reported by 202 patients (56%) at baseline and by 188 (52%) on treatment. Sleep problems at baseline were independently associated with a higher risk of earlier death (HR: 1.36; p = 0.011), progression (HR: 1.43; p = 0.002) and poor treatment response (RR: 0.58; p = 0.016). TDC analysis confirmed the independent prognostic effect of sleep problems on OS (HR: 1.37; p = 0.008), while on treatment this effect was only observed using univariate analysis. The negative prognostic value of sleep problems on OS at baseline, on treatment, and as a TDC was greatest on chronoFLO4 compared to FOLFOX2. Conclusions: Subjective sleep problems are associated with poor clinical outcomes in metastatic colorectal cancer patients and affect chronotherapy effectiveness. There is a need for a well-tuned circadian timing system in order to increase chronotherapy activity. Prospective studies are needed for determining the impact of therapeutic approaches on sleep disorders upon quality of life and survival of cancer patients

An Investigation of Stationarity Properties of the Turkish Tourism Income Variable

Tourism has a significant impact on economic growth as put forth by the tourism-led growth hypothesis. Turkey’s earnings from tourism were 31.5 billion dollars in 2015 according to TURKSTAT. This implies that tourism is an important industry for Turkey and has a significant impact on economy. Therefore, the question whether a policy implementation in tourism is long-lasting or not is critical for both the industry and whole economy. This study researches the persistence of policies in tourism industry, employing tourism income series for period of 2009M1-2015M12 and tests the stationarity of this series using traditional unit root tests as well as a wavelet-based unit root test developed by Fan and Gencay (2010). Both seasonally adjusted and unadjusted series have been used. The empirical results point out that the traditional unit root test has a proclivity to report that tourism income series is I(1) or non-stationary. On the other hand, the waveletbase unit root test indicates that tourism income is stationary. The empirical result of wavelet-based test implies that impact of a shock on this sector is transitory. The income in tourism industry will return more or less back to its meaning the following year

Big data-driven prediction of airspace congestion

Air Navigation Service Providers (ANSP) worldwide have been making a considerable effort for the development of a better method to measure and predict aircraft counts within a particular airspace, also referred to as airspace density. An accurate measurement and prediction of airspace density is crucial for a better managed airspace, both strategically and tactically, yielding a higher level of automation and thereby reducing the air traffic controller's workload. Although the prior approaches have been able to address the problem to some extent, data management and query processing of ever-increasing vast volume of air traffic data at high rates, for various analytics purposes such as predicting aircraft counts, still remains a challenge especially when only linear prediction models are used. In this paper, we present a novel data management and prediction system that accurately predicts aircraft counts for a particular airspace sector within the National Airspace System (NAS). The incoming Traffic Flow Management (TFM) data is streaming, big, uncorrelated and noisy. In the preprocessing step, the system continuously processes the incoming raw data, reduces it to a compact size, and stores it in a NoSQL database, where it makes the data available for efficient query processing. In the prediction step, the system learns from historical trajectories and uses their segments to collect key features such as sector boundary crossings, weather parameters, and other air traffic data. The features are fed into various regression models, including linear, non-linear and ensemble models, and the best performing model is used for prediction. Evaluation on an extensive set of real track, weather, and air traffic data including boundary crossings in the U.S. verify that our system efficiently and accurately predicts aircraft counts in each airspace sector.Comment: Submitted to the 2023 IEEE/AIAA Digital Aviation Systems Conference (DASC

Finite element modeling and experimental studies on mixed mode-I/III fracture specimens

In this study, finite element modeling and experimental studies on a mode-I/III specimen similar to the compact tension specimen are presented. By using bolts, the specimen is attached to two loading apparatus that allow different levels of mode-I/III loading by changing the loading holes. Specimens having two different thicknesses are analyzed and tested. Modeling, meshing and the solution of the problem involving the whole assembly, i.e., loading devices, bolts and the specimen, with contact mechanics are performed using ANSYSTM. Then, the mode-I/III specimen is analyzed separately using a submodeling approach, in which threedimensional enriched finite elements are used in FRAC3D solver to calculate the resulting stress intensity factors along the crack front. In all of the analyses, it is clearly shown that although the loading is in the mode-I and III directions, mode-II stress intensity factors coupled with mode-III are also generated due to rotational relative deformations of crack surfaces. The results show that the mode-II stress intensity factors change sign along the crack front and their magnitudes are close to the mode-III stress intensity factors. It is also seen that magnitudes of the mode-III stress intensity factors do not vary much along the crack front. Fracture experiments also performed and, using the stress intensity factors from the analyses and crack paths and surfaces are shown

Lymph node metastasis in grossly apparent clinical stage Ia epithelial ovarian cancer: Hacettepe experience and review of literature

Background Lymphadenectomy is an integral part of the staging system of epithelial ovarian cancer. However, the extent of lymphadenectomy in the early stages of ovarian cancer is controversial. The objective of this study was to identify the lymph node involvement in unilateral epithelial ovarian cancer apparently confined to the one ovary (clinical stage Ia). Methods A prospective study of clinical stage I ovarian cancer patients is presented. Patient's characteristics and tumor histopathology were the variables evaluated. Results Thirty three ovarian cancer patients with intact ovarian capsule were evaluated. Intraoperatively, neither of the patients had surface involvement, adhesions, ascites or palpable lymph nodes (supposed to be clinical stage Ia). The mean age of the study group was 55.3 ± 11.8. All patients were surgically staged and have undergone a systematic pelvic and paraaortic lymphadenectomy. Final surgicopathologic reports revealed capsular involvement in seven patients (21.2%), contralateral ovarian involvement in two (6%) and omental metastasis in one (3%) patient. There were two patients (6%) with lymph node involvement. One of the two lymph node metastasis was solely in paraaortic node and the other metastasis was in ipsilateral pelvic lymph node. Ovarian capsule was intact in all of the patients with lymph node involvement and the tumor was grade 3. Conclusion In clinical stage Ia ovarian cancer patients, there may be a risk of paraaortic and pelvic lymph node metastasis. Further studies with larger sample size are needed for an exact conclusion.PubMedWoSScopu

Relevance of a mobile internet platform for capturing inter- and intrasubject variabilities in circadian coordination during daily routine : pilot study

Background: Experimental and epidemiologic studies have shown that circadian clocks disruption can play an important role in the development of cancer and metabolic diseases. The cellular clocks outside the brain are effectively coordinated by the body temperature rhythm. We hypothesized that concurrent measurements of body temperature and rest-activity rhythms would assess circadian clocks coordination in individual patients, thus enabling the integration of biological rhythms into precision medicine. Objective The objective was to evaluate the circadian clocks’ coordination in healthy subjects and patients through simultaneous measurements of rest-activity and body temperature rhythms. Methods Non-invasive real-time measurements of rest-activity and chest temperature rhythms were recorded during the subject’s daily life, using a dedicated new mobile e-health platform (PiCADo). It involved a chest sensor that jointly measured accelerations, 3D-orientation and skin surface temperature every 1-5 min, and relayed them out to a mobile gateway via Bluetooth-Low-Energy. The gateway tele-transmitted all stored data to a server via GPRS every 24 h. The technical capabilities of PiCADo were validated in 55 healthy subjects and 12 cancer patients, whose rhythms were e-monitored during their daily routine for 3-30 days. Spectral analyses enabled to compute rhythm parameters values, with their 90% confidence limits, and their dynamics in each subject. Results All the individuals displayed a dominant circadian rhythm in activity with maxima occurring from 12:09 to 20:25. This was not the case for the dominant temperature period, which clustered around 24 h for 51 out of 67 subjects (76%), and around 12 h for 13 others (19%). Statistically significant sex- and age- related differences in circadian coordination were identified in the non-cancerous subjects, based upon the range of variations in temperature rhythm amplitudes, maxima (acrophases), and phase relations with rest-activity. The circadian acrophase of chest temperature was located at night for the majority of people, but it occurred at daytime for 26% (14/55) of the non-cancerous people and 33% (4/12) of the cancer patients, hence supporting important inter-subject differences in circadian coordination. Sex, age and cancer significantly impacted on the circadian coordination of both rhythms, based on their phase relationships. Conclusions Complementing rest-activity with chest temperature circadian e-monitoring revealed striking inter-subject differences regarding human circadian clocks coordination and timing during daily routine. To further delineate the clinical importance of such finding, the PiCADo platform is currently applied for both the assessment of health effects resulting from atypical work schedules, and the identification of the key determinants of circadian disruption in cancer patients