Learning Financial Networks with High-frequency Trade Data.

Financial networks are typically estimated by applying standard time series analyses to price-based economic variables collected at low-frequency (e.g., daily or monthly stock returns or realized volatility). These networks are used for risk monitoring and for studying information flows in financial markets. High-frequency intraday trade data sets may provide additional insights into network linkages by leveraging high-resolution information. However, such data sets pose significant modeling challenges due to their asynchronous nature, complex dynamics, and nonstationarity. To tackle these challenges, we estimate financial networks using random forests, a state-of-the-art machine learning algorithm which offers excellent prediction accuracy without expensive hyperparameter optimization. The edges in our network are determined by using microstructure measures of one firm to forecast the sign of the change in a market measure such as the realized volatility of another firm. We first investigate the evolution of network connectivity in the period leading up to the U.S. financial crisis of 2007-09. We find that the networks have the highest density in 2007, with high degree connectivity associated with Lehman Brothers in 2006. A second analysis into the nature of linkages among firms suggests that larger firms tend to offer better predictive power than smaller firms, a finding qualitatively consistent with prior works in the market microstructure literature.

Uncertainty and unmet care needs before and after surgery in patients with gastric cancer: A survey study.

Uncertainty and unmet care needs constantly change in patients with cancer. However, there is a lack of information regarding the changing pattern of these variables. This study aimed to examine the changes in uncertainty and unmet care needs at diagnosis and after surgery among patients with gastric cancer. In total, 86 individuals completed a self-reported questionnaire. Data were collected twice - to measure uncertainty and unmet care needs at cancer diagnosis (T1), and after surgery (T2) - and analyzed using descriptive analysis and a dependent t-test. Uncertainty was moderate at both periods but significantly higher at T1. Unmet care needs were highest in the information domain and lowest in the sexuality domain at both T1 and T2. Only the physical/daily living domain were significantly higher at T2, whereas the information, psychological, and patient care/support domains were significantly higher at T1. Different levels of uncertainty and unmet needs were identified at T1 and T2. Healthcare providers should assess changing unmet care needs at each stage of the cancer trajectory and provide related nursing care and information to this population, even immediately after diagnosis.

Who are the assistant cooks at the community child centers in South Korea? Focus group interviews with workfare program participants.

PURPOSE: Community child centers (CCCs) were introduced to provide after-school activities and care, including meal services to children from low-income families. The assistant cooks, who have the main responsibility for making and serving food at CCCs, are a major factor influencing the eating habits of children using CCCs. In this study, we tried to identify and understand who the assistant cooks are, what their job responsibilities are, and what they need in order to be able to provide children with healthy meals. METHODS: Three focus group interviews were held with 17 workfare program participants who worked as assistant cooks at CCCs, and content analysis methods were applied using the NVivo 12 qualitative data analysis software. RESULTS: The assistant cooks reflected on their perceptions of the children's health at the CCCs, their own cooking style, and their role at the CCCs. Additionally, barriers to the optimal provision of their services were pointed out, and improvements were suggested. CONCLUSION: The results of this study can be used as a fundamental resource for the development of tailored interventions that consider a child's unique environment to address health disparities, specifically with respect to childhood obesity.

Unmet Needs for Clinical Ethics Support Services in Nurse: Based on focus group interviews.

BACKGROUND: As nurses' ethical competence in their own fields is essential, clinical ethics support services help nurses improve ethical competence. OBJECTIVES: The purpose of this study was to identify the unmet needs of ethical support for nurses in clinical settings and explore the differences by nursing units. RESEARCH DESIGN: Focus group interview design was applied. Participants and research context: Data were collected via four rounds of focus group interviews with 37 nurses at intensive care units, medical-surgical units, emergency departments and oncology units. Major questions were as follows: 'What is nurses' experience of ethical difficulties while working as a clinical nurse?' and 'What kinds of clinical ethics support services do nurses require in different clinical settings?' Inductive content analysis was performed to analyse the data. Ethical considerations: Ethical approval was obtained from the institutional review of board at the College of Nursing. FINDINGS: Five categories (with 14 subcategories) were identified: difficulty providing evidence-based care, lack of support in maintaining patients' and family members' dignity, insufficient education regarding clinical ethics, loss of professional self-esteem and expectations concerning organizational support. Nurses' desire for ethical support varied according to department. CONCLUSION: Nurses face both practical and existential ethical issues that require rapid solution each day. There is a need for ethical counselling to prevent compassion fatigue and identify means via which nurses reflect on their daily lives in their own fields. In-house training should be provided for each unit, to improve ethical competence and facilitate the development of pragmatic, sensible solutions.

A Randomized Comparison of Medication and Cognitive Behavioral Therapy for Treating Depression in Low-Income Young Minority Women.

BACKGROUND Longitudinal data arise frequently in biomedical science and health studies where each subject is repeatedly measured over time. We compared the effectiveness of medication and cognitive behavioral therapy on depression in predominantly low-income young minority women. MATERIAL AND METHODS The treatment effects on patients with low-level depression may differ from the treatment effects on patients with high-level depression. We used a quantile regression model for longitudinal data analysis to determine which treatment is most beneficial for patients at different stress levels over time. RESULTS The results confirm that both treatments are effective in reducing the depression score over time, regardless of the depression level. CONCLUSIONS Compared to cognitive behavioral therapy, treatment with medication more often effective, although the size of the effect differs. Thus, no matter how severe a patient's depression symptoms are, antidepressant medication is effective in decreasing depression symptoms.

[Experience of treatment adherence in Korean patients with HIV].

PURPOSE: The purpose of this study was to explore the subjective experience of Highly active Antiretroviral therapy (HAART) adherence in Korean patients with HIV. METHODS: A phenomenological methodology was used for the study. Data were collected from March to December, 2013 using open-ended questions during in-depth interviews. Participants were taking HAART for HIV, and were contacted through purposive techniques. RESULTS: Four men and 4 women whose average treatment period was 5.9 years participated in this study. Seven themes emerged from the analysis using Colazzi's method: (a) Seizing life in a deep sense of despair, (b) Struggling with medication, (c) Facing harsh treatment from health care providers, (d) Spoiling healthy pattern, (e) Hungering for communication and emotional support, (f) Turning to accepting HIV, (g) Becoming adherent to HIV treatment. CONCLUSION: Prejudice from health care providers and lack of emotional support were barriers to HAART in Korea. Intervention strategies are needed to decrease prejudices from health care providers and to increase family support.

Validation of a new food frequency questionnaire for assessment of calcium and vitamin d intake in korean women.

BACKGROUND: Validated simple calcium questionnaires are available to assess the intake of calcium and vitamin D in western countries, but they are not appropriate for Koreans since dairy products are not the major source of calcium and vitamin D in Korea. Thus, the objective of the present study was to develop and validate a simple and easy food frequency questionnaire (FFQ) of calcium and vitamin D for Korean. METHODS: Two hundred and fifty-six women were asked to complete the validated FFQ used by the Korean National Health and Nutrition Examination Survey (KNHANES) and a newly developed FFQ, the Korean Calcium Assessment Tool (KCAT), which contain the 7 food groups with 24 categories of 45 food items that are consumed frequently by Koreans. RESULTS: Calcium intake was not significantly different between the two methods; Pearson's correlation coefficient of 0.98 indicated a positive correlation, and Cohen's kappa coefficient of 0.78 indicated the subjects were correctly classified. Bland-Altman plot also showed that the mean differences of the calcium intake as assessed by the two methods were in high agreement. However, the vitamin D intake assessed by KCAT was significantly higher than that assessed by the FFQ used in KNHANES. The vitamin D intakes as assessed by the two methods were positively correlated but the two methods were in moderate agreement. CONCLUSIONS: The results suggested that the newly developed KCAT was a valid tool for assessing the calcium intake in Korean women, but it might overestimate the vitamin D intake.

Low-dose lenograstim to enhance engraftment after autologous stem cell transplantation: a prospective randomized evaluation of two different fixed doses.

BACKGROUND: G-CSF is used to enhance hematopoietic recovery after autologous stem cell transplantation (ASCT), but the optimal dose of G-CSF during engraftment has not been established. The medical cost of ASCT is a serious financial burden in developing countries, and G-CSF is the most costly drug used in this procedure. We evaluated whether a lower, vial-size fitted dose of lenograstim is clinically equivalent to a higher fixed dose. STUDY DESIGN AND METHODS: A prospective randomized study was performed on 33 patients (11 non-Hodgkin's lymphoma, 8 multiple myeloma, 14 breast cancer) undergoing ASCT. Patients were randomly administered 100 micro g or 250 micro g lenograstim daily starting on the next day of ASCT, with a minimum infusion of 3 x 10(6) CD34+ cells per kg. RESULTS: For both lenograstim doses, median time to neutrophil engraftment was 9 days and median time to PLT engraftment was 11 days. Episodes of clinically documented infections were 10 per 379 patient-days in the 100 microg per day group and 10 per 320 patient-days in the 250 microg per day group. There were no between-group differences in requirements for transfusion of RBCs or PLTs. Duration of hospitalization was 16 days for the 100 microg per day group and 17 days for the 250 microg per day group. Daily lenograstim dose per patient's body weight and total amount of lenograstim used during ASCT were both significantly lower in the 100 microg per day group. CONCLUSION: Administration of 100 microg per day of lenograstim showed comparable clinical efficacy to 250 microg per day lenograstim for immediate hematopoietic recovery after ASCT. Use of the lower dose was associated with lower overall lenograstim usage and lower cost.