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In this paper, the experimental and numerical investigations of both swirling hybrid rocket motors without and with the design of regenerative cooling (RC hereafter), using 90%-wt H 2 O2 and polypropylene (PP) as the liquid oxidizer and the solid fuel, respectively, were performed and compared. We implemented a new design of regenerative cooling using the oxidizer to transfer the heat generated from combustion. A series of ground horizontal hot-fire tests, which include the catalytic-bed only and the motor without/with RC were performed to measure the propulsion performance related parameters. The resulting C* efficiency of the RC design with catalytic-bed only remained in comparison with the one without RC. With a similar initial combustion chamber geometry, the RC implementation resulted in a better engine Isp efficiency from 96.3 to 98.6 with a lower O/F ratio from 6.49 to 5.94. In addition, the topologies of the burned fuel grain surface were optically measured by a 3D laser scanner. The resulting variation of regression rates between the upstream and downstream fuel for the chamber with the RC was smaller than case without the RC. Moreover, a simplified semi-empirical computational fluid dynamics (CFD) model based on the measured regression rates was constructed for investigating the physical phenomenon inside the hybrid rocket combustion chamber. The simulations show that a higher swirling number in the later portion of the port was found for the RC case. By concerning about the different O/F ratios and port size of the burned fuel, a series of simplified numerical CFD investigation with a fixed O/F and a fixed port size varying the regression rates from upstream to downstream fuel systematically with the same average region rate was performed to complement the semi-empirical CFD simulations. The results showed that there were two distinct regions including an upstream non-classical region dominated by the gas impingement of gas and a downstream classical region caused by the swirling effect of gases. In the non-classical region, the calculated distributions of the swirling numbers of the former are essentially the same for all the cases no matter what the magnitude of the regression rate is, while in the classical region higher swirling numbers are found for the case of more uniform distribution of regression rates. Heat generated near the upstream of the fuel grain was transferred more efficiently through the design of RC, which makes the resulting fuel regression more uniform than that without RC. The resulting swirling efficiency in the RC case was higher than that without RC. The HRM with RC hence had a better engine Isp efficiency with a lower O/F ratio.

Leukemia relapse rarely presents with ophthalmic manifestations. We report on a 62-year-old woman with relapse of Philadelphia chromosome–positive acute lymphoblastic leukemia who presented with ocular infiltration as the sole presentation. The diagnostic difficulties are also discussed.

We propose a new readout paradigm for enhancing the performance of wireless resistive and reactive sensors. Here, we consider a passive resistor–inductor–capacitor sensor that is inductively coupled to an active reader, with the equivalent circuit of the whole telemetry system obeying the space-time reflection symmetry or the parity–time (PT) symmetry. As inspired by PT-symmetric quantum systems, this circuit has a non-Hermitian effective Hamiltonian that commutes with the antilinear, combined ${\mathcal {PT}}$ operator, where ${\mathcal {P}}$ and ${\mathcal {T}}$ are parity-inversion and time-reversal operators. We demonstrate that the PT-symmetric wireless sensor system, when compared to conventional interrogation techniques using a passive coil antenna, may provide significantly improved quality factor ( ${Q}$ -factor), sensing resolution, and sensitivity in response to the sensor’s reactance or resistance variation. Our results may have an impact on various wireless sensing, detection, and imaging systems, particularly for emerging micromachined sensors, miniature implants, wearables, and Internet-of-Things applications.

We present here new types of self-powered, low-interference wireless sensors based on graphene circuits, which can have dual functions: chemical sensing at the molecular level and radio-frequency (RF) modulation. We demonstrate that a fully passive, graphene-based harmonic (transponder) sensor can display a chemically sensitive frequency multiplication effect, which, when linked to a hybrid-fed small antenna, can realize an ultrasensitive, low-profile, light-weight, and potentially flexible RF sensor. We have designed two different types of circuits comprising back-gate graphene field-effect transistors (GFETs) and compared in detail their performance and implementation complexity. We have also proposed a reliable readout method based on the machine learning for extracting the mean value and the fluctuation of chemical doping levels in GFETs. The proposed graphene-based harmonic sensor may potentially benefit a wide range of sensing applications, including, but not limited to, power-efficient, real-time monitoring of chemical/gas exposures and biological agents, as well as emerging wearable and implantable devices.

Solving multi-dimensional eigenmodes problem for elliptic operator using radial basis functions (RBFs) was proposed by Platte and Driscoll (2004) [14] . They convert the eigenmodes problem to an eigenpairs problem of a finite dimensional matrix. We formulate an approach based on using finite order interpolating polynomials as eigenfunctions for eigenmodes problem. We prove that, under some simple conditions on the RBFs, two approaches converge when increasingly flat BRFs are being used. These results are supported by numerical examples.

Introduction Obstructive Sleep Apnea (OSA) is a type of sleep disorder characterized by intermittent, partial or complete upper airway collapse. Mostly, moderate to severe OSA cases were recommended to treat with continuous positive airway pressure, however, some of them were withdrawn. Transoral robotic surgery (TORS) was considered for OSA patient with tongue base hypertrophy, but the success rate was only 66.9% and the symptoms might relapse because of aging and gaining weights. Myofunctional therapeutic training (MFTT) was also an alternative treatment for patients with mild to moderate OSA. In our study, we investigated the effect of TORS surgery and oropharyngeal MFTT for OSA patients. Methods Seven adult patients were recruited, who were newly diagnosed with moderate to severe OSA (Apnea-hypopnea Index, AHI, 49.8±27.7/h). Polysomnography, questionnaire (Pittsburgh sleep quality index, PSQI; Snore Outcomes Survey, SOS), and the muscle strengths over tongue and jaw-opening were assessed before TORS surgery, 6-week and 18-week after surgery. The components of MFTT program involved jaw opening, tongue protrusion, tongue left, tongue right, tongue up and tongue down. It began at 6th week after surgery and these patients underwent 12 weeks of the home-based oropharyngeal MFTT. During the training intervention period, subjects were interviewed every week for adjusting the treatment intensity. Results Mean age was 45.9 years old (SD 9.8) and body mass index (BMI) was 26.6 (SD 3.6). After combination treatment of TORS surgery and MFTT, AHI-supine was significantly decreased from 66.3/h to 26.8/h (p Conclusion Our study presented that combination of TORS surgery and oropharyngeal MFTT could improve OSA severity and symptoms. Support This work was supported by National Cheng-Kung University Hospital (grant number NCKUH-10802018).

We present a comprehensive description of the blastomylonites of the Ikat thrust localized within the Ikat terrane in the East Transbaikalian branch of the Central Asian Orogenic Belt. The metamorphic rocks of the Garga block are thrust over the almost unmetamorphosed Cambrian deposits of the Ikat Formation. The geologic position of the thrust and the structure and mineral and petrochemical compositions of the blastomylonites in the suture zone are considered, and U–Pb dating of detrital zircon is carried out. The blastomylonites develop after the gneisses of the Garga block; the block protolith, admixed with felsic volcanic material, was no older than the Neoproterozoic (750–800 Ma). The 40Ar/39Ar age of the thrust is estimated at 282 ± 0.4 Ma based on metamorphic biotite from the blastomylonites. The thrust marks the transpression period during the Late Paleozoic processes of tectonometamorphic activity related to the subduction of the Mongol–Okhotsk oceanic crust beneath the Siberian continent.

A novel octa-band LV-shape printed monopole antenna fed by a coplanar waveguide (CPW), using two inverted-L strips and a LV-shape radiating stub is proposed and investigated. The proposed antenna has a simple planar structure and occupies area of 30 × 35 mm2 on the system circuit board of the portable communication devices. The simulated and measured octa-band monopole antenna frequencies cover the GSM850/900/1800/1900/DCS/PCS/UMTS and WLAN (2.4 GHz, 5.2 GHz and 5.8 GHz) band operations for S 11 ≤ – 10 dB. The measured peak gains are 3, 2.33, 5, and 3.3 dBi with sufficient bandwidths to cover modern portable communication devices. The simulated and measured results show a good agreement. This proposed antenna with multiband, broadband matched impedance, stable radiation patterns, constant antenna gains and compact size is suitable for multi-mode applications.

The fabrication of metal-base transistors (MBTs) based on InGaZnO at room temperature is reported for the first time. With a suitable oxygen doping to the sputtering-deposited InGaZnO film and an HfSiO interlayer, improved diode performances with enhanced Schottky barrier heights of 0.70 and 0.66 eV are obtained for the base/collector (Ti/InGaZnO) and base/emitter (Au/HfSiO/InGaZnO) junctions, respectively. InGaZnO MBT using a Ti(10 nm)/Au(10 m)/HfSiO(5 nm) dual metal base shows a high common-emitter current gain ( β ) 840-310 at V CE = 2 V and I B ranging from 1 to 10 nA.

In this paper we present a convergence analysis for a fitted finite-volume discretization method for the two-dimensional Black―Scholes equation arising in the Hull-White model for pricing European options with stochastic volatility. We first formulate the finite-volume method as a nonconforming Petrov― Galerkin finite-element method with each basis function of the trial space being determined by a set of two-point boundary-value problems defined on element edges. We then show that the bilinear form of the finite-element method is coercive and continuous. Finally we establish an upper bound of order O(h) on the discretization error of method, where h denotes the mesh parameter of the discretization.

Background: It has been proposed that the volatile anesthetic isoflurane induces neuroprotection and that the endogenous opioid peptide dynorphin induces neurocytotoxicity in cells. The levels of dynorphin are often significantly elevated in neuropathophysiological conditions, and dynorphin can directly induce toxicity. However, the neuroprotective effects of isoflurane on dynorphininduced cytotoxicity are still unclear. Methods: In order to determine the effect of isoflurane on dynorphin-induced cytotoxicity in neuronal cells, we have designed a device wherein cultured human neuroblastoma SH-SY5Y cells can be exposed to isoflurane. Fully differentiated SH-SY5Y cells were obtained by treating the cells with retinoic acid for 6 days. We examined SH-SY5Y cell survival, apoptosis, and antiapoptotic protein expression by cell viability, terminal deoxynucleotidyl transferasemediated dUTP nick end-labeling stain, and Western blot analysis, respectively. Results: After 16h of dynorphin (10 mM) treatment, the SHSY5Y cells showed significant cytotoxicity, apoptosis, and downregulation of the antiapoptotic Bcl-2 protein expression. These effects of dynorphin were significantly inhibited by isoflurane exposure for 32h [pretreatment for 16h and posttreatment (after dynorphin treatment) for 16h]. Conclusion: Thus, our results suggest that isoflurane exerts neuroprotective effects in the case of dynorphininduced pathophysiological disruption.

The purpose of this study is to set up BMI evaluation index, I BMI, as the tool for assessing the effects of weight control programs. A large number of improvement plans were brought up to settle obesity problems; however, those plans could involve up to thousands or even tens of thousands of subjects. With I BMI, the results and effects of the plans can be evaluated by sampling, a feature of I BMI. Therefore, I BMI serves as an accurate, easy and convenient way of measuring group BMI.

It is known that the memory is relevant in the symmetric phase of the minority game. In our previous work we have successfully explained the quasi-periodic behavior of the game in the symmetric phase with the help of the probability theory. Based on this explanation, we are able to determine how the memory affects the variance of the system in this paper. By using some particular types of fake history such as periodic type and random type, we determine how efficient the memory has been used in the standard game. Furthermore, the analysis on the effective memory strongly supports the result we proposed previously that there are three distinct phases in the minority game.

This paper refers to the process capability indices in the field of management to set up Body Mass Indices (BMI), which can be used to evaluate and compare the BMI values of people at different ages as a group. A large number of improvement plans were brought up to settle obesity problems; however, there could be up to thousands or even tens of thousands of subjects involved. With BMI, the results and effects of the plans can be evaluated by sampling, a characteristic of BMI. Therefore, BMI has served as an accurate, easy and convenient measurement to evaluate group BMI.

Summary. We assessed the efficacy of interferon (IFN) alpha-2b plus ribavirin therapy in patients with hepatitis C virus (HCV)-related cirrhosis, and elucidated the risk factors for the development of hepatocellular carcinoma (HCC) to determine whether these therapies might reduce the incidence of HCC. One hundred and thirty-two HCV-cirrhotic patients receiving IFN alpha-2b (3 or 5 MU thrice weekly) and oral ribavirin (1000–1200 mg/day) for 24 or 48 weeks were analysed. Cumulative incidence of HCC was estimated by the Kaplan–Meier method. The prognostic relevance of clinical variables and HCC occurrence was evaluated by univariate analysis with the log-rank test and by multivariate Cox's regression analysis. A total of 116 patients completed the treatment and 73 (55%) achieved a sustained virological response (SVR). Stepwise logistic regression analysis showed that nongenotype 1b (P

This study investigated photocatalysis of MTBE via both UV/TiO 2 and H 2 O 2 -UV/TiO 2 processes. Several experimental parameters including pH level, H 2 O 2 concentration, TiO 2 dosage and light intensity were investigated. The experimental results demonstrated the degradation of MTBE following a pseudo first-order reaction in both reaction systems. Faster degradation rates were observed in alkaline solution for the UV/TiO 2 system, but for the H 2 O 2 -UV/TiO 2 system, faster degradation rates were detected in acidic solution. More dosage of TiO 2 and irradiated light intensity were beneficial for the photocatalysis of MTBE. However, a peak reaction rate was observed at a TiO 2 concentration of about 500 mg/L. The experimental results also indicated that the degradation rate of MTBE was enhanced by the addition of H 2 O 2 . H 2 O 2 could be a more efficient electron acceptor than oxygen for retarding recombination of electron-hole pairs. The degradation rate in the H 2 O 2 -UV/TiO 2 system was about 2.8 times faster than that in the UV/TiO 2 system for solution pH below 5, and the rate increased 30% for solution pH above 6. In addition, it is observed that the reaction rate of MTBE increased quickly with H 2 O 2 concentration at low H 2 O 2 dosages, but the rate was independent of H 2 O 2 dosage when adding too much H 2 O 2 .

Due to the extensive application of artificial nitrogen-based fertilizers on land, groundwater from the central part of Taiwan faces problems of increasing concentrations of nitrate, which were measured to be well above 30 mg/L all year round. For meeting the 10 mg/L nitrate standard, optimal operations for a heterotrophic denitrification pilot plant designed for drinking water treatment was investigated. Ethanol and phosphate were added for bacteria growing on anthracite to convert nitrate to nitrogen gas. Results showed that presence of high dissolved oxygen (around 4 mg/L) in the source water did not have a significantly negative effect on nitrogen removal. When operated under a C/N ratio of 1.88, which was recommended in the literature, nitrate removal efficiency was measured to be around 70%, sometimes up to 90%. However, the reactor often underwent severe clogging problems. When operated under C/N ratio of 1.0, denitrification efficiency decreased significantly to 30%. Finally, when operated under C/N ratio of 1.5, the nitrate content of the influent was almost completely reduced at the first one-third part of the bioreactor with an overall removal efficiency of 89–91%. Another advantage for operating with a C/N ratio of 1.5 is that only one-third of the biosolids was produced compared to a C/N value of 1.88.

In this study, we investigated the surface modification of reinforcement fibers for composites by acid treatments, including PBO fiber, Kevlar fiber and carbon fiber. The corresponding changes in the surface free energy components were carefully evaluated using a Cahn dynamic contact angle analysis system. In addition, the fiber's surface elemental composition and topography were studied using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The results showed that the surface nitrogen-to-carbon (N/C) and oxygen-to-carbon (O/C) ratios were significantly increased after the treatments. The surface free energy γ of PBO fiber was increased from 43.3 mJ/m2 to 58.5 mJ/m2 or by 35% with 60 wt% methanesulfonic acid solution treatment for 36 h. However, the increase with 60 wt% nitric acid solution was only by 14% (to 49.5 mJ/m2) for the same treatment time.

Fine pore ceramic diffuser aeration, a very competitive high efficiency system, is widely used in aerobic biological processes for providing dissolved oxygen and mixing. Concern has been registered regarding the maintenance of these systems and their susceptibility to diffuser fouling. Selected ceramic diffusers, removed from the Madison Metropolitan Sewage District (MMSD) Nine Springs Wastewater Treatment Plant, Wisconsin, U.S.A., were fractured and analyzed in an attempt to identify the elemental components of the internal foulants and to evaluate the effect of acid cleaning on diffuser performance. The fouling condition of diffusers were initially characterized by dynamic wet pressure (DWP) measurements. Microimages taken from the non acid-treated diffuser profile using scanning electronic microscopy revealed the structural difference of internal foulants which may correspond to the stage of foulant formation. For diffuser samples from the MMSD facility, calcium phosphate minerals were predominant foulants, although some calcium carbonate and organic carbon have also accumulated. The clogging of diffuser internal void space was verified by observing thin sections of diffuser cross-sections. Selected diffusers were then treated with strong acid to study its effectiveness in removing internal foulant by acid soaking. Even though the acid treated diffusers showed significant reduced DWP values, acid treatment, the common diffuser cleaning technique, does not completely remove these internal foulants. This may be the reason why the acid-treated diffusers never reached like-new conditions. Furthermore, once these acid-treated diffusers are installed back to the aeration tank, these dewatered foulant sections may very well behave as seed for future clogging.

The photocatalysis of azo dye, Orange G, by P-25 anatase TiO2 was investigated in this research. The experiments were conducted in a batch reactor with TiO2 powder suspension. Four near-UV lamps were used as the light source. The experimental variables included solution pH level, amount of TiO2, illumination light intensity, and reaction time. A pseudo-first order reaction kinetic was proposed to simulate the photocatalytic degradation of Orange G in the batch reactor. More than 80% of 10 mg/L Orange G decomposition in 60-minute reaction time was observed in this study and fast decomposition of Orange G only occurred in the presence of both TiO2 and suitable light energy. Faster degradation of Orange G was achieved under acid conditions. The degradation rates of Orange G at pH = 3.0 were about two times faster than those at pH = 7.0. Faster degradation of azo dye was observed for greater irradiated light intensity and more TiO present during the reaction. The reaction rates were proportional to TiO2concentration and light intensity with the power order of 0.726 and 0.734, respectively.

The fate of thiocyanate (SCN−) and cyanate (OCN−) under methanogenic conditions was investigated at 35 °C. Thiocyanate and cyanate were added to mixed methanogenic cultures along with an organic mixture. Thiocyanate was stable under these conditions, and had no adverse effect on methanogenesis at a concentration as high as 2.5 mM. In contrast, cyanate at a concentration as low as 0.3 mM initially inhibited methanogenesis but, after the complete removal of cyanate, methanogenesis gradually recovered. The inhibitory effect of cyanate on methanogenesis became more profound with repeated additions of cyanate. The transformation of cyanate followed the hydrolytic route to ammonia and bicarbonate under anaerobic conditions and its hydrolysis rate was enhanced by microbial activity. Cyanide was not detected as a cyanate transformation product under the methanogenic conditions of this study.

Abrin is a toxic protein consisting of two subunits, an enzymatic A chain (ABRaA) and a lectin-active B chain (ABRaB), linked by a disulfide bond. Site-directed mutagenesis was performed using PCR to study how the conserved amino acid residues, Tyr74, Tyr113, Glu164 and Trp198, around the active site of ABRaA are involved in enzyme catalysis, enzyme-substrate recognition and reassociation of ABRaA with ABRaB. The protein biosynthesis inhibitory activities of Y74F, Y113F and W198F were decreased moderately to that of wild type reABRaA, while that of E164Q decreased dramatically. Kinetic analysis showed that the kat of Y74F, Y113F and W198F resembled that of wild type, while the Km increased significantly. W198F did not reassociate with ABRaB to form heterodimers, while Y74F, Y113F and E164Q did. SDS-PAGE analysis of ABRaA treated with trypsin showed that reABRaA, Y74F, Y113F and E164Q survived digestion, whereas W198F was not protected from digestion. CD spectra revealed that W198F showed significant conformational changes. These observations suggest that E164 is directly involved in catalysis, and Tyr74, Tyr113 and Trp198 in substrate binding, while Trp198 also plays an important role in maintaining the conformation of ABRaA required for its reassociation with ABRaB.

Thanks to the MEMS and SoC technologies, the wireless sensor networks (WSN) enabled inertial sensor node (ISN) can be implemented on a very small printed circuit board (PCB). A miniaturized printed monopole antenna with metallic grid is proposed for the small ISN. The binary particle swarm optimization (PSO) is employed to find the optimized configuration of the metallic grids with the specified bandwidth and antenna efficiency. Comparisons of the simulated optimized antenna and the corresponding fabricated antennas are also studied. The proposed antenna and the design procedure can be applied to most antenna design for small wireless sensors and provides low-cost antenna solution.

Early diagnosis of serious bacterial infection (SBI) in young infants is a difficult problem by clinical symptoms and signs. The goal of this study is to evaluate the predictive value of plasma IP-10 levels for early diagnosis of SBI in young infants4 months of age.We enrolled pediatric patients who were4 months of age with a clinical suspicion to have SBI admitted in neonatal intensive care unit or complete nursing unit of Pediatric Department of Kaohsiung Medical University Hospital. Blood was drawn for measurement of complete blood counts, C-reactive protein (CRP) and plasma IP-10 levels and microbiological cultures were obtained at the time of admission.There were 60 patients enrolled in this study. The SBI group (n = 21) have higher plasma IP-10 levels than those infants without SBI (n = 39) [median 104.8 (range 0-1457.1) versus 0 (range 0-129.3) pg ml(-1), P = 0.0161 after adjusting age]. A plasma IP-10 level48.2 pg ml(-1) had the best diagnostic accuracy for indicating SBI {sensitivity 81.0% [95% confidence interval (CI) 71.1-90.1%]; specificity 94.9% [95% CI 65.4-87.0%]; positive likelihood ratio 15.9, negative likelihood ratio 0.2}.In infants who were4 months of age with suspicion of SBI, IP-10 assay might be a good predictor. Key words: chemokine, IP-10, serious bacterial infection, young infant, C-reactive protein.

In the present work we use Raman microscopy to investigate the size effect of spin-phonon coupling in antiferromagnetic Cr2O3 nanoparticles. The peculiarities of the dependency of the phonon wave number on temperature (with a relatively weak peak at 293 cm(-1)) can be attributed to the spin-phonon coupling. The variation with temperature of the spin-phonon mode develops when the antiferromagnetic state is near the ordering temperature of the Cr spins. The observations can be reasonably well interpreted by describing the order parameter. A shift in frequency is caused by a strong spin-phonon interaction in Cr2O3. The obtained s-ph coefficients are found to be consistent with the strain, where raising the strain results in weakening of the s-ph coupling.

Background: Cytochrome P450 (CYP) 2J2 is a regulatory enzyme in the biosynthesis of biologically active cis-epoxyeicosatrienoic acids (EETs). EETs have been suggested to modulate PPAR-γ and PPAR-α transcription activity and play a role in stimulus-secretion coupling in pancreatic beta cells. Genetic abnormalities in the expression of CYP2J enzymes may play a role in the pathogenesis of type 2 diabetes mellitus (T2DM). Our objective was to investigate CYP2J2 G-50T polymorphism (rs890293) in association with insulin resistance markers and T2DM in a Chinese population. Methods: A total of 1747 Chinese T2DM patients and 994 non-diabetic subjects were studied. The CYP2J2 G-50T polymorphism was determined by a restriction fragment-length polymorphism polymerase chain reaction. Results: Neither the CYP2J2 genotype distribution nor allele frequency differed between the control subjects and the T2DM patients. However, among diabetics, subjects with a younger age at diagnosis (AAD