Nano-inspired fluidic interactivity for boiling heat transfer: Impact and criteria

The enhancement of boiling heat transfer, the most powerful energy-transferring technology, will lead to milestones in the development of high-efficiency, next-generation energy systems. Perceiving nano-inspired interface functionalities from their rough morphologies, we demonstrate interface-induced liquid refreshing is essential to improve heat transfer by intrinsically avoiding Leidenfrost phenomenon. High liquid accessibility of hemi-wicking and catalytic nucleation, triggered by the morphological and hydrodynamic peculiarities of nano-inspired interfaces, contribute to the critical heat flux (CHF) and the heat transfer coefficient (HTC). Our experiments show CHF is a function of universal hydrodynamic characteristics involving interfacial liquid accessibility and HTC is improved with a higher probability of smaller nuclei with less superheat. Considering the interface-induced and bulk liquid accessibility at boiling, we discuss functionalizing the interactivity between an interface and a counteracting fluid seeking to create a novel interface, a so-called smart interface, for a breakthrough in boiling and its pragmatic application in energy systems

Micro-nano hybrid structures with manipulated wettability using a two-step silicon etching on a large area

Nanoscale surface manipulation technique to control the surface roughness and the wettability is a challenging field for performance enhancement in boiling heat transfer. In this study, micro-nano hybrid structures (MNHS) with hierarchical geometries that lead to maximizing of surface area, roughness, and wettability are developed for the boiling applications. MNHS structures consist of micropillars or microcavities along with nanowires having the length to diameter ratio of about 100:1. MNHS is fabricated by a two-step silicon etching process, which are dry etching for micropattern and electroless silicon wet etching for nanowire synthesis. The fabrication process is readily capable of producing MNHS covering a wafer-scale area. By controlling the removal of polymeric passivation layers deposited during silicon dry etching (Bosch process), we can control the geometries for the hierarchical structure with or without the thin hydrophobic barriers that affect surface wettability. MNHS without sidewalls exhibit superhydrophilic behavior with a contact angle under 10°, whereas those with sidewalls preserved by the passivation layer display more hydrophobic characteristics with a contact angle near 60°

Fully integrated lab-on-a-disc for simultaneous analysis of biochemistry and immunoassay from whole blood

We report a fully integrated device that can perform both multiple biochemical analysis and sandwich type immunoassay simultaneously on a disc. The whole blood is applied directly to the disposable "lab-on-a-disc" containing different kinds of freeze-dried reagents for the blood chemistry analysis as well as reagents required for the immunoassay. The concentrations of different kinds of analytes are reported within 22 min by simply inserting a disc to a portable device. Using the innovative laser irradiated ferrowax microvalves together with the centrifugal microfluidics, the total process of plasma separation, metering, mixing, incubation, washing, and detection is fully automated. The analyzer is equipped with an optical detection module to measure absorbances at 10 different wavelengths to accommodate the various kinds of reaction protocols. Compared to the conventional blood analysis done in clinical laboratories, it is advantageous for point-of-care applications because it requires a smaller amount of blood (350 mu L vs. 3 mL), takes less time (22 min vs. several days), does not require specially trained operators or expensive instruments to run biochemical analysis and immunoassay separately.close554

Classification of rice (oryza sativa l. japonica nipponbare) immunophilins (fkbps, cyps) and expression patterns under water stress

<p>Abstract</p> <p>Background</p> <p>FK506 binding proteins (FKBPs) and cyclophilins (CYPs) are abundant and ubiquitous proteins belonging to the peptidyl-prolyl <it>cis/trans </it>isomerase (PPIase) superfamily, which regulate much of metabolism through a chaperone or an isomerization of proline residues during protein folding. They are collectively referred to as immunophilin (IMM), being present in almost all cellular organs. In particular, a number of IMMs relate to environmental stresses.</p> <p>Results</p> <p>FKBP and CYP proteins in rice (<it>Oryza sativa </it>cv. Japonica) were identified and classified, and given the appropriate name for each IMM, considering the ortholog-relation with <it>Arabidopsis </it>and <it>Chlamydomonas </it>or molecular weight of the proteins. 29 FKBP and 27 CYP genes can putatively be identified in rice; among them, a number of genes can be putatively classified as orthologs of <it>Arabidopsis </it>IMMs. However, some genes were novel, did not match with those of <it>Arabidopsis </it>and <it>Chlamydomonas</it>, and several genes were paralogs by genetic duplication. Among 56 IMMs in rice, a significant number are regulated by salt and/or desiccation stress. In addition, their expression levels responding to the water-stress have been analyzed in different tissues, and some subcellular IMMs located by means of tagging with GFP protein.</p> <p>Conclusion</p> <p>Like other green photosynthetic organisms such as <it>Arabidopsis </it>(23 FKBPs and 29 CYPs) and <it>Chlamydomonas </it>(23 FKBs and 26 CYNs), rice has the highest number of IMM genes among organisms reported so far, suggesting that the numbers relate closely to photosynthesis. Classification of the putative FKBPs and CYPs in rice provides the information about their evolutional/functional significance when comparisons are drawn with the relatively well studied genera, <it>Arabidopsis </it>and <it>Chlamydomonas</it>. In addition, many of the genes upregulated by water stress offer the possibility of manipulating the stress responses in rice.</p

Long-term balloon indwelling technique for the treatment of single benign biliary stricture

We aimed to evaluate the feasibility and safety of long-term balloon indwelling technique for the treatment of single benign biliary stricture. Five patients with single benign biliary stricture were included from December 2014 to November 2016. The patients were three men and two women with a mean age of 50 years (range, 30–65 years). A balloon catheter was inserted into the drainage catheter and emerged through the side hole of the catheter so that the balloon and drainage catheters could be placed together at the stricture site. Follow-up fluoroscopic examination was performed at least once every 2 weeks to evaluate the adequacy of expansion and location of the balloon. The balloon was reinflated at each session, and then removed after an approximately two-month indwelling period. The catheters used were 10–16 French and the diameter of indwelling balloons were 4–8 mm. The primary technical and clinical success rates were 100%. Maintenance of the balloon location was achieved in 25 of 26 follow-up fluoroscopic examinations (mean, 5.2 times per patient) with a rate of 96.1%. The mean follow-up period after successful removal of the balloon was 542.2 days (range, 93–1042 days), and there were no recurrences in the five cases. The long-term balloon indwelling technique is a good way to induce maximal dilatation at the stricture site without large diameter skin and subcutaneous tract dilatation and can be successfully used for single benign biliary stricture

Clinico-genetic study of nail-patella syndrome

Nail-patella syndrome (NPS) is an autosomal dominant disease that typically involves the nails, knees, elbows and the presence of iliac horns. In addition, some patients develop glomerulopathy or adult-onset glaucoma. NPS is caused by loss-of-function mutations in the LMX1B gene. In this study, phenotype-genotype correlation was analyzed in 9 unrelated Korean children with NPS and their affected family members. The probands included 5 boy and 4 girls who were confirmed to have NPS, as well as 6 of their affected parents. All of the patients (100%) had dysplastic nails, while 13 patients (86.7%) had patellar anomalies, 8 (53.3%) had iliac horns, 6 (40.0%) had elbow contracture, and 4 (26.7%) had nephropathy including one patient who developed end-stage renal disease at age 4.2. The genetic study revealed 8 different LMX1B mutations (5 missense mutations, 1 frame-shifting deletion and 2 abnormal splicing mutations), 6 of which were novel. Genotype-phenotype correlation was not identified, but inter- and intrafamilial phenotypic variability was observed. Overall, these findings are similar to the results of previously conducted studies, and the mechanism underlying the phenotypic variations and predisposing factors of the development and progression of nephropathy in NPS patients are still unknown

Prevalence and Risk Factor of Erosive Esophagitis Observed in Korean National Cancer Screening Program

Prevalence of erosive esophagitis (EE) has been increasing in Korea. The purpose of this study was to estimate prevalence of EE among low socioeconomic population in Korea and to investigate risk factors for EE. We reviewed the medical records of 7,278 subjects who were examined by upper endoscopy in the Korean National Cancer Screening Program at Chung-Ang University Yong-san Hospital from March 2003 to March 2008. The study population included subjects ≥ 40 yr of age who were Medicaid recipients and beneficiaries in the National Health Insurance Corporation. Multivariate analysis was used to determine risk factors for EE. Prevalence of EE was 6.7% (486/7,278). According to the LA classification system, LA-A in 344 subjects, LA-B in 135 subjects, and LA-C and D in 7 subjects. In multivariate analysis, age ≥ 60 yr, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and endoscopic hiatal hernia were significant risk factors for EE. The prevalence of EE in low socioeconomic Korean population is similar to that in personal annual medical check-ups. Risk factors for EE among them include old age, male sex, BMI ≥ 25, current smoking, alcohol consumption, fasting glucose level ≥ 126 mg/dL, and hiatal hernia