Effect of Flow Direction of Heating Medium on Boiling Heat Transfer Characteristics in a Single-Channel Plate-Fin Heat Exchanger

This study deals with evaporative heat transfer characteristics of vertically upward flows in single-channel plate-fin heat exchangers. R-134a was used as the refrigerant. The refrigerant channel was sandwiched by two water channels with the same channel shape. The refrigerant was heated by hot water from the both side. In this experiment, pressure of the working fluid was maintained at 0.665 MPa (saturation temperature is 25 °C)．Subcooled liquid with the subcooling of 5 and 10 K, or wet vapor with the quality of 0.1 was supplied to the evaporator. Two kinds of offset fin, Fin A and B, whose fin pitch were 1.95 and 3.175 mm, respectively, were used. The channel hydraulic diameter with Fin A and Fin B were 1.78 and 2,89 mm, respectively. Effects of the fin pitch and flow direction of the heating water, such as counter and parallel flow arrangements, on the heat transfer rate, pressure drop, and wall temperature distribution on the outside of the water channel were examined. The wall temperature was visualized by an IR camera. As the results, it was shown that the effects of the flow direction of water and the fin pitch on the heat transfer rate were a little due to a dryout in the refrigerant flows. However, a large difference in the wall temperature distribution between the counter and parallel flow was observed. The difference might be caused by the phase distribution of refrigerant, and lead to the increase in the pressure drop for the parallel flow. For the parallel flow arrangement, the temperature on the right side with the water inlet port was quite higher than the right side. The temperature distribution was kept over the heat exchanger. The tendency was weaker for Fin B with the larger fin pitch due to phase separation caused by gravity

Association between Public Assistance and Frequent Emergency Department Visits in Urban Areas of Japan: A Case-Control Study

Emergency department（ED）crowding due to frequent visitors increases medical costs and endangers the safety of patients who need prompt treatment. Although some studies have examined the social background of frequent visitors to the ED, there are few comprehensive studies of factors related to frequent ED visits in Japan. The present study examined whether public assistance status, age, and underlying conditions are associated with frequent visits to the ED. Subjects in this study were patients over 20 years of age who visited the ED of General Medicine in Showa University Hospital in Tokyo, Japan, from April 1, 2014, to March 31, 2015（n＝6,182）. Information regarding sex, age, public insurance, hypertension, diabetes mellitus, dyslipidemia, chronic obstructive pulmonary disease, cancer, dysuria, bronchial asthma, and chronic kidney disease was collected using a patient database created from medical and hospital records. Based on a previous study, subjects who visited the ED four or more times were defined as frequent visitors, while those who visited the ED less than four times were considered infrequent visitors. Logistic regression analysis was performed to calculate odds ratios（ORs）and 95％ confidence intervals（CIs）for frequent ED visits. Receipt of public assistance significantly increased the OR for frequent visits（4.26, 95％ CI: 1.90-9.56）, even after adjusting for sex, age, and potential confounding factors（OR: 3.89, 95％ CI: 1.62-9.35）. The current study found a significant association between frequent ED visits and the receipt of public assistance. Emergency physicians and medical practitioners need to share information with outpatient physicians and welfare officers and work together with patients to address their specific medical and social vulnerabilities

Serum IgG4 as a biomarker reflecting pathophysiology and post-operative recurrence in chronic rhinosinusitis

Background: Type 2 chronic rhinosinusitis (CRS), especially eosinophilic CRS (ECRS), is an intractable upper airway inflammatory disease. Establishment of serum biomarkers reflecting the pathophysiology of CRS is desirable in a clinical setting. As IgG4 production is regulated by type 2 cytokines, we sought to determine whether serum IgG4 levels can be used as a biomarker for CRS. Methods: Association between the serum IgG4 levels and clinicopathological factors was analyzed in 336 CRS patients. Receiver operating characteristics (ROC) analysis was performed to determine the cut-off value of serum IgG4 levels that can be used to predict the post-operative recurrence. Results: Serum IgG4 levels were significantly higher in patients with moderate to severe ECRS versus those with non to mild ECRS. The levels were also significantly higher in asthmatic patients and patients exhibiting recurrence after surgery compared to controls. ROC analysis determined that the best cut-off value for the serum IgG4 level to predict the post-operative recurrence was 95 mg/dL. The corresponding sensitivity and specificity were 39.7% and 80.5%, respectively. When we combined the two cut-off values for the serum IgG4 and periostin, patients with high serum levels of either IgG4 or periostin exhibited a high post-operative recurrence (OR: 3.95) as compared to patients having low serum levels of both IgG4 and periostin. Conclusions: The present results demonstrate that the serum IgG4 level is associated with disease severity and post-operative course in CRS. In particular, the combination of serum IgG4 and periostin could be a novel biomarker that predicts post-operative recurrence

Repertoire Memorization in Jazz Vol. 2 : Do College Jazz Programs Address the Subject?

The aim of this study is to explore to what extent and how different jazz programs on the college level include repertoire memorization in their curriculums. By repertoire memorization I mean the study and memorization of a certain amount of standard jazz repertoire, which include songs from the so-called great American songbook and tunes by jazz composers that are commonly played by jazz musicians around the world.  Whether the schools include repertoire memorization in their official curriculum or course descriptions or leave the subject to the discretion of the individual instructors is explored. Methods for teaching the subject, methods of assessing the students’ memorization, and views of different jazz department heads regarding the importance of the subject are also investigated. A sociocultural perspective is adopted in the study to see if academia attempts to address or perhaps recreate some of the sociocultural contexts that jazz learning existed in before jazz was included in music conservatories and universities. Eleven jazz programs and one jazz educator were asked to be a part of the study and of those, four schools responded. The data was collected in email correspondence with the four different department heads that were from the United States, Finland and Sweden (two schools). The results showed that the programs in Finland and the United States placed great importance on the subject and use required repertoire lists that the students were tested on. One of the Swedish programs had suggested repertoire lists for students without formal testing and the other Swedish program left the subject up to the individual instructors although the subject did seem to be encouraged. One unexpected observation from the repertoire lists used from the schools in Finland and the United States was that there were a surprisingly large number of songs that were not in common to both lists