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The crystallization and thermal degradation behaviors of poly(3-hydroxybutyrate) (PHB) filled with surface-modified silicas were analyzed by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and dynamic thermogravimetric analysis (TG). The results of FTIR and TG confirmed that the substantial amounts of methyl methacrylate (MMA) and amidoamine (AMDA) were successfully grafted onto the hydrophilic silica surfaces. From DSC and TG analyses, it was indicated that the crystallization rate, crystallinity, melting temperature ( T), content of the high T crystals, and thermal stability of PHB were affected by the type and amount of the silicas used and changed with the grafted chemicals. The hydrophobic silica has a better effect on enhancing crystallization rate and thermal stability of PHB than the hydrophilic silica due to the better compatibility with PHB. However, the MMA and AMDA grafted onto the hydrophilic silica surfaces effectively improved the crystallization and degradation effects of the hydrophilic silica. The addition of two parts AMDA-modified silica in a hundred parts PHB has the best improvement in terms of of the crystallization, melting characteristics, and thermal stability of PHB. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the effectiveness of a really simple syndication (RSS)-based Clinical Reminding System (RCRS) in reminding clinicians to complete their unfinished clinical works. The study was conducted in a hospital in Taiwan. In the study, the information was collected from the hospital information system (HIS) and the RCRS was integrated with the computerized physician order entry (COPE) system.

The crystallization and thermal degradation of polyhydroxybutyrate (PHB) blended with a small amount of carboxyl-terminated butadiene acrylonitrile rubber (CTBN) and biocompatible polyvinylpyrrolidone (PVP) are analyzed by differential scanning calorimetry (DSC), dynamic thermogravimetric analysis (TG), gel permeation chromatography (GPC), polarized optical microscope (POM), and wide angle X-ray diffraction (WAXD). From results of DSC, TG, and GPC, it is shown that the presence of PVP or CTBN could affect the crystallization rate, crystallinity, melting temperature, and thermal stability of PHB. The changes of crystal sizes by the added CTBN and PVP are also confirmed by the POM and WAXD analyses. The addition of the 1 wt% PVP or CTBN into PHB can significantly increase the crystallization rate and thermal degradation temperature, and affect the degradation kinetics of PHB due to the steric hindrance effects of the added PVP and CTBN on retarding the degradation reaction. The best improvement of the thermal stability is obtained from the PVP-modified PHB. The method of using CTBN or PVP to improve the thermal stability of PHB is of great processing advantages in industry because it is functional with low purity PHB, henceforth, saves the cost of the purification process. [ABSTRACT FROM AUTHOR]

The flow boiling heat transfer in microchannels have become important issue because it is extremely high-performance heat exchanger for electronic devices. For a detailed study on flow boiling heat transfer in a microtube, we have used a transparent heated microtube, which is coated with a thin gold film on its inner wall. The gold film is used as a resistance thermometer to directly evaluate the inner wall temperature averaged over the entire temperature measurement length. At the same time, the transparency of the film enables the observation of fluid behavior. Flow boiling experiments have been carried out using the microtube under the following conditions; mass velocity of 105 kg/m2 s, tube diameter of 1 mm, heat flux in the range of 10 ~ 380 kW/m2 s, and the test fluid used is ionized water. Under low heat flux conditions, the fluctuations in the inner wall temperature and mass velocity are closely related; the frequency of these fluctuations is the same. However, the fluctuations in the inner wall temperature and heat transfer coefficient are found to be independent of the fluctuation in the mass velocity under high heat flux conditions. [ABSTRACT FROM AUTHOR]

Many patients with gastroesophgeal reflux disease (GERD) may also have overlapping symptoms of dyspepsia. This study was to examine if GERD patients could be separated into meaningful groups based on their gastric myoelectrical characteristics. The study included 20 GERD patients with dyspeptc symptoms (GERD+) and 17 patients with GERD. Gastric myoelectrical activity was assessed using cutaneous electrodes to record electrogastrograms (EGGs). The GERD+ patients ingested smaller volumes of water compared to patients with GERD (P < 0.05). At baseline, the percentage of gastric myoelectrical power in the normal 3-cpm range was significantly less in patients with GERD+ compared with the GERD subjects (P = 0.01). Power in the bradygastria range was significantly greater in patients with GERD+ (P = 0.005). The GERD+ group had a significant increase in the percentage of power in the tachygastria range later after ingesting the water load (P < 0.01). In conclusion, this study has shown that more gastric dysrhythmias were detected in the GERD+ patients accompanied with altered perception of stomach fullness. [ABSTRACT FROM AUTHOR]

Gastroesophageal reflux disease (GERD) is a disorder that is related to an incompetent lower esophageal sphincter (LES). Previous studies showed that bombesin could increase LES pressure in humans and opossums. The aim of the present study was to characterize the effects of bombesin on porcine LES contraction. We used the selective agonists, neuromedin B (NMB), gastrin-releasing peptide (GRP), and [D-Tyr6,Apa-4Cl11,Phe13,Nle14]bombesin-(6-14) (DTACPN-BN), as well as receptor antagonists of bombesin receptor subtype 2 (BB2), and 3 (BB3) for ex vivo contraction studies. Atropine, nifedipine, tetrodotoxin, and ω-conotoxin GVIA were used to explore the agonist-induced LES contraction mechanism. Reverse transcription polymerase chain reaction and immunohistochemistry were applied to detect bombesin receptor expression. Our results indicate that GRP and DTACPN-BN, but not NMB, induced tonic contractions of the porcine LES in a dose-dependent manner, and the contractions were inhibited with selective BB2 and BB3 antagonists. The GRP-induced contraction is mainly caused by L-type Ca2+ channel-mediated Ca2+ influx. However, DTACPN-BN-induced contractions are associated with neuronal conduction. RT-PCR and immunohistochemistry revealed that BB2 and BB3 were expressed in the porcine LES. Bombesin-induced tonic contraction of the LES is mediated through BB2 and BB3. Bombesin, BB2, and BB3 agonists might have the potential to treat GERD. [ABSTRACT FROM AUTHOR]