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BACKGROUND Laser speckle contrast imaging (LSCI) is widely accepted as a powerful visualization tool for quantifying blood flow in tissues. The benefits of this technology include simplicity of configuration, ease of use, and intuitive results. With significant advancements in smartphone and camera technologies, recent attempts have been made to develop a smartphone-based LSCI application that can be used as a Point-Of-Care (POC) device to examine vascular disorders in situ. OBJECTIVE A novel smartphone-based portable LSCI endoscope device was developed and validated to perform endoscopic POC testing for the diagnosis of vascular disorders in vivo. METHODS Device implementation: The flexible endoscope consisted of compact light sources (white LED and green laser), imaging optics, and a flexible fiberscope assembled in a 3D printed hand-held cartridge for access and illumination of the cavity organs in the body. The rear camera of the smartphone was mounted on an endoscope for endoscopy and LSCI image acquisition and processing. Tissue-mimicking phantom flow experiment: A 2.5% microparticle mixture was injected into a light-transparent silicon tube with inner-diameter 1.0 mm, submerged in a tissue-mimicking gel to mimic blood flow in tissue. It was then pumped at a constant flow rate (0.023–0.094 ml/min) using a syringe pump. The perfused phantom was imaged using the prototype endoscopic device. In vivo small animal experiment: Healthy Sprague–Dawley rats (n=2) and 0.05% BBN-induced bladder cancer rat models (n=3) were intravenously anesthetized. Their bladders were emptied by rinsing the inner sidewalls with a PBS solution. The probe tip of the endoscope device was used to gain access to the bladder sidewall via the urinary tract for examination. RESULTS Blood flow phantom experiment: Tissue phantom blood flow was visualized using raw laser speckle images of the developed endoscope device. The flow was quantified as a speckle flow index (SFI), which showed linearity with the preset pump flow rate. In vivo small animal experiment: The bladders of healthy and cancerous rats were distinguishable in structure and vasculature. CONCLUSIONS The low-cost portable mobile endoscope device for monitoring blood flow and perfusion changes using a smartphone can be beneficial as a primary diagnostic tool for patients at home and as a cost-effective POC testing assay.

An in-house method, employing magnetic stirring-assisted aqueous extraction combined with gas chromatography-flame ionization detector, for determination of ethanol in different foods and beverages was validated according to the ISO/IEC 17025 standard. Validation parameters, including selectivity, method limits of detection (approx. 0.006 mg/g) and quantification (approx. 0.02 mg/g), linearity (R2 of >0.999), trueness (relative biases of

This study investigated the relationship between satisfaction of program participation and perception of successful aging in female elderly participating in oriental medicine Qigong exercise. The oriental medicine Qigong exercise program applied to the elderly women, and obtained the following results by verifying the effects of program participation satisfaction, an independent variable on the perception of successful aging, a dependent variable. First, MANOVA of participation satisfaction and successful aging perception showed significant differences in the background variables such as age, family members, educational background, exercise experience, number of training, and economic situation, etc. Second, in the multiple regression analysis which was conducted to investigate the participants' satisfaction with program participation and the effect on overall perception of successful aging, the regression model was found to be statistically significant. The results of this study showed that the appropriateness of oriental medicine Qigong exercise as an effective leisure program in the old age was confirmed, and it will be meaningful to provide basic data as an elderly leisure welfare policy in future.

A reactive chromatography process was investigated for a transesterification reaction of propylene glycol methyl ether (DOWANOL™ PM) using a homogeneous catalyst, a sodium alkoxide. In the proposed process, fresh catalyst is supplied with desorbent, which allows independent optimization of the adsorption properties of the stationary phase. Deactivation of catalytic activity can be avoided, which had been found to be the bottleneck in our previous study for heterogeneous catalysis. To model and optimize this process, a series of batch reaction experiments, and pulse injection tests with a chromatographic column with and without reaction were carried out. From the experimental data, equilibrium and kinetic parameters were estimated using the inverse method. Using this model, a simulated moving bed reactor was designed that achieves a conversion of 95% using the homogeneous catalysis concept.

This work proposes a practical and systematic model-based approach to identify the optimal operating conditions for a simulated moving bed reactor (SMBR). The SMBR operation is applied to an industrial case study for the continuous production of a solvent, propylene glycol methyl ether acetate (DOWANOL™ PMA), which is produced through an acid-catalyzed esterification reaction of 1-methoxy-2-propanol and acetic acid. The model-based approach is demonstrated by lab-scale SMBR experiments. A multi-objective optimization problem was formulated for developing an SMBR process to maximize the production rate of PMA and the conversion of the esterification reaction simultaneously. In this study, this optimization problem is solved using the epsilon-constrained method and a Pareto plot is presented. The solutions that corresponded to three different values of conversion, 70%, 80%, and 85%, are experimentally validated. The SMBR model that was developed from batch kinetic and single column chromatography experiments demonstrates reasonable agreement with the experimental results. Furthermore, the SMBR experimental data was used to correct the parameters in the model. A validation study at a higher conversion of 95% demonstrates improved predictability of the corrected parameters.

Reactive chromatography using an anion exchange resin is proposed for a transesterification reaction of propylene glycol methyl ether (DOWANOL™ PM) with ethyl acetate to produce propylene glycol methyl ether acetate (DOWANOL™ PMA). This reaction is studied in batch and chromatographic reactors catalyzed by an anion exchange resin. Several anion exchange resins are tested and compared based on the performance of resin as an adsorbent and a catalyst. A chromatographic column is packed with a selected catalyst, AMBERLITE™ IRA904, and both reaction and chromatographic elution are studied at different temperatures and feed concentrations. The resulting chromatograms are fitted to a mathematical model to obtain adsorption equilibrium and reaction kinetic parameters by the inverse method. Compared to esterification investigated in a previous study, transesterification has advantages such as a higher conversion at lower temperature and easy removal of the byproduct which may lead to higher productivity. Deactivation of anion exchange resins is observed and potential solutions are suggested.

In this study, the thermodynamic inhibition effects of choline chloride (ChCl, a hydrogen bond acceptor), urea (a hydrogen bond donor), and their mixture (deep eutectic solvent, DES) on CH4 hydrates were investigated with both experimental and computational approaches. The synthesis of DES from the mixture of ChCl and urea was confirmed by measuring its melting temperature through a high-pressure micro-differential scanning calorimeter. Sigma (σ)-profiles of ChCl, urea, and DES obtained by the COSMO-RS software indicated that these substances have great potential to be used as thermodynamic hydrate inhibitors (THIs). The three-phase (gas hydrate (H) – liquid water (Lw) – vapor (V)) equilibria of CH4 hydrates in the presence of ChCl (1.0, 3.0, and 5.0 mol%), urea (1.0, 3.0, and 5.0 mol%), and DES (3.0 mol%) demonstrated that ChCl, urea, and DES contributed to the significant shift of hydrate equilibrium temperature to inhibition regions at a specified pressure and thus can function as effective THIs. Moreover, quantum theory of atoms in molecules (QTAIM) analysis also demonstrated that the strength of hydrogen bonding between inhibitor molecules and hydrate cages (small 512 and large 51262 cages) of CH4 hydrates was in the order of ChCl > DES > urea, which was consistent with experimental results. The experimental and computational results from this study would be helpful for a better understanding of the inhibition mechanism of ChCl, urea, and DES and for their possible application to flow assurance in oil and gas pipelines.

This study developed an insect-repellent film incorporated with star anise essential oil (SAEO). The insect-repellent emulsion coating (IEC) was applied to a base layer of polyethylene terephthalate. To control the rate of SAEO released from the IEC, three types of laminate film with different gas transmission rates were used, including low-density polyethylene film, polypropylene film of 20-μm thickness, and polypropylene film of 30-μm thickness (PP30). When prepared at a laboratory-scale, the PP30 proved the most efficacious in providing long-lasting insect-repellent activity and the sensory attributes of the PP30 were not significantly different (p > 0.05) from those of the control film (i.e., without the IEC layer). Therefore, the PP30 selected for further analysis. The active film was then manufactured at a pilot-scale using a rotogravure printing press, and its mechanical and optical properties were evaluated. Although the active film had a similar appearance with the control film to the naked eye, the active film had relatively lower tensile strength and elongation at break values, and it was less transparent with a more reddish color. Finally, the active film was applied as bread packaging, and the results suggested that as a food packaging material, the film showed excellent insect-repellent activity. Therefore, the developed active film in the pilot-scale has applicability to a real food system.

As an industrial case study, esterification of acetic acid with 1-methoxy-2-propanol using a cation exchange resin has been investigated using a well-stirred batch reactor and chromatographic reactor. Well-stirred batch reactor experiments were conducted over different operating conditions to analyze the reaction equilibrium and kinetics. It was found that the final conversion was limited by equilibrium, and temperature had no significant effect on increasing the final conversion. Parameters in a reaction rate model were obtained at different temperatures (50–90 °C). Since the well-stirred batch experiment alone was not enough to capture the adsorption behavior of the system, pulse injections of each component into the chromatographic column were conducted to obtain the adsorption parameters. The esterification reaction was performed systematically in a lab-scaled chromatographic reactor at different flow rates (0.2–1 ml/min), injection volumes (0.05 ml, 0.5 ml), and temperatures (70–110 °C). A mathematical model for isothermal equilibrium dispersive model was implemented and parameters were determined by fitting the model to the experimental data. It was observed that when the injection volume of single component was too large, two reaction sites were formed inside the column, resulting in a deformed peak shape of the product in the outlet chromatogram. Nearly 100% of conversion, which was infeasible in the well-stirred batch reactor, was achieved when the flow rate was low and the injection volume was small. The results indicate that the chromatographic reactor enhanced the reaction beyond the equilibrium by separating the products from the reaction sites.

Objective: Different dry-aging methods [traditional dry-aging (TD), simplified dry-aging (SD), and SD in an aging bag (SDB)] were compared to investigate the possible use of SD and/or SDB in practical situations. Methods: Sirloins from 48 Hanwoo cows were frozen (Control, 2 days postmortem) or dry-aged for 28 days using the different aging methods and analyzed for chemical composition, total aerobic bacterial count, shear force, inosine 5'-monophosphate (IMP) and free amino acid content, and sensory properties. Results: The difference in chemical composition, total aerobic bacterial count, shear force, IMP, and total free amino acid content were negligible among the 3 dry-aged groups. The SD and SDB showed statistically similar tenderness, flavor, and overall acceptability relative to TD. However, SDB had a relatively higher saleable yield. Conclusion: Both SD and SDB can successfully substitute for TD. However, SDB would be the best option for simplified dry-aging of low-marbled beef with a relatively high saleable yield.

Protease IV (PIV), a key virulence factor of Pseudomonas aeruginosa is a secreted lysyl-endopeptidase whose expression is induced by quorum sensing (QS). We found that PIV expressed in QS mutant has severe reduction of activity in culture supernatant (CS), even though it is overexpressed to high level. PIV purified from the QS mutant (M-PIV) had much lower activity than the PIV purified from wild type (P-PIV). We found that the propeptide cleaved from prepro-PIV was co-purified with M-PIV, but never with P-PIV. Since the activity of M-PIV was restored by adding the CS of QS-positive and PIV-deficient strain, we hypothesized that the propeptide binds to and inhibits PIV, and is degraded to activate PIV by a QS-dependent factor. In fact, the CS of the QS-positive and PIV-deficient strain was able to degrade the propeptide. Since the responsible factor should be a QS-dependently expressed extracellular protease, we tested QS-dependent proteases of P. aeruginosa and found that LasB (elastase) can degrade the propeptide and activate M-PIV. We purified the propeptide of PIV and confirmed that the propeptide can bind to and inhibit PIV. We suggest that PIV is post-secretionally activated through the extracellular degradation of the propeptide by LasB, a QS-dependent protease.

We evaluated the antioxidant and antimicrobial activities of various leafy herbal tea (LHT) extracts, including rooibos, green tea, black tea, rosemary, lemongrass, mulberry leaf, bamboo leaf, lotus leaf, peppermint, persimmon leaf, and mate tea. To compare the antioxidant activities of various LHTs, samples of each were extracted with 80 °C water or 20 °C ethanol, and their total phenolic content (TPC), total flavonoid content (TFC), 2,2-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, 2,2-azinobis-3 ethyl benxothiazoline-6-sulphonic acid (ABTS) radical cation decolorization activity, ferric reducing power, and ferrous ion chelating effect were measured. Green tea ethanol extract showed the highest antioxidant activity in all assays except the ferrous ion-chelating assay. Water extracts of green tea and black tea and ethanol extracts of rosemary, mate, and persimmon leaf teas also exhibited considerable antioxidant potential, followed by the green tea ethanol extract. Minimum inhibitory concentrations (MIC) and minimum lethal concentrations (MLC) were determined to verify the antimicrobial activities of the LHT extracts against two oral pathogens (Streptococcus mutans and Streptococcus sobrinus) and three food-borne pathogens (Listeria monocytogenes, Shigella flexneri, and Salmonella enterica). Among the tested LHTs, green tea ethanol extract had potent antimicrobial activity against all five pathogens, and the mate tea water extract was the most effective against Gram-positive bacteria. Consequently, green tea ethanol extracts had the most powerful antioxidant and antimicrobial properties, suggesting their potential application as a health-promoting functional ingredient or natural preservative in foods.

A piezoelectric ultrasonic bone surgical instrument, usually used to remove the tartar out of teeth or to cut the dentine of the tooth, is a recently popular instrument for dental treatment due to its several merits such as small size, low-electric power and precision control of surgical operation. It has typically two parts of a tip and vibration system which is also composed of head, piezoelectric elements and tail-mass. In order to improve the performance of the instrument, it is important to standardize the size of the vibration system without tip for high performance. In this study, a Finite Element Analysis (FEA) was utilized to optimize the structure of ultrasonic instrument in vibration system. Consequently, this study revealed that influence of several tips on property were minimized and it showed good property at the frequency range of 22~32 kHz.

The full scale Soil Cement Mixing (SCM) wall was constructed to investigate viability of the wall. Long term behavior of the wall resulted in viability of the wall. However, design guidelines on SCM wall are limited due to its complex geometry. In this paper, the three dimensional finite element method is employed to study the influence of various design decisions for SCM wall. The numerical model is first calibrated with an instrumented case history. Then a parametric study is constructed. The results give information on the influence of the following factors on the wall behavior: size of column, column overlapping, column embedment, existence of relieving platform, and column strength. The implications in design are discussed.

This study was an initial step to evaluate grape seeds from the waste products of the food industry as nutraceutical materials. Grape seeds of Campbell Early cultivar (Vitis labrusca × Vitis vinifera) were dried and pulverized followed by extraction with absolute methanol. The total phenolic content of grape seed extract (GSE) was 80.82 mg gallic acid equivalent/g seed. The amount of total flavonoids was 27.04 mg (+)-catechin equivalents/g of grape seed. GSEs exhibited antioxidant activities of 60.13 mg ascorbic acid equivalent/g seed and 209.45 mg Trolox equivalent/g seed for 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid), respectively. GSE inhibited lipid accumulation of C3H10T1/2 and 3T3-L1 cells in a dose-dependent manner. Inhibition was also associated with reduced expression of PPARγ, the master regulator of adipocyte differentiation. Further study is needed to identify specific molecules which attribute bioactivities of GSE. PRACTICAL APPLICATIONS Overall, the observed antioxidant and antiobesity activities of Campbell Early seeds suggest that they could be used as a functional and nutraceutical ingredient as well as preservative ingredient in foods. Results verified the efficacy of new value-added material from agricultural by-products. Eventually, we plan to develop a natural antioxidant additive using GSE in expectation of retarding lipid oxidation and providing other functionality.

This study was conducted to discover the differences in physicochemical and sensory qualities of beef from 4-year-old Hanwoo cows and 2-year-old Hanwoo steers after undergoing different meat aging methods. Additionally, the possibility of using 4-year-old cows as value-added aged meat was investigated. Loins from eight cows (average 51 months old) and eight steers (average 28 months old) of quality grade 2 were aged for 28 days using dry and wet aging. Analyses were conducted to evaluate meat quality, including moisture content, pH, cooking loss, shear force, nucleotides, free amino acids (FAA), and sensory evaluation. After 28 days of aging, the moisture and shear force for loins from steers and cows were reduced compared with those of non-aged meat (P < 0.05). Cooking loss was reduced by dry aging. Regardless of aging method and gender, aging decreased inosine-5ʹ-monophosphate content but increased FAA content (P < 0.05). Dry aging increased glutamic acid content in meat, and aging the meat of steer increased the content of aspartic acid and glutamic acid (P < 0.05). Before aging, sensory scores for juiciness, tenderness, flavour, and overall acceptance between cow and steer were significantly different (P < 0.05), but the differences disappeared after aging. Therefore, the quality of lower grade meat from 4-year-old cows is comparable to that of meat from 2-year-old steers after aging, regardless of the aging method used.

A K-band low-power miniaturized planar-type hyperthermia system was developed to replace massive and expensive equipment. The system consists of a VCO with a buffer amplifier, a high-power amplifier module, a 20-㏈-coupled line coupler, a chip circulator and two power detectors for signal generation, amplification and power monitoring. All these components have been implemented in planar form on two module blocks. The total size of the hyperthermia system was less than 10×6.5×3 ㎤. In order to verify the system performance, ablations were carried out on nude mice xenografted with human breast cancer. Ablation results show performance comparable to the massive components-based system. This work shows the feasibility of a low-cost miniaturized hyperthermia system for practical clinical applications.

A planar bi-directional microwave heat applicator integrated with active circuits on a single platform is presented in this paper. K-band frequencies have been utilized to facilitate low-power hyperthermia and high-level integration. The active source module implemented with GaAs-based multichip monolithic microwave integrated circuits delivers 1.4 W at 20 GHz into the co-integrated planar applicator, which has three planar coaxial apertures on each side for wide-area bi-directional hyperthermia. The heating volume is further enhanced by employing switched heating, which effectively doubles the hyperthermic volume. The bio-heat equation is solved to find the optimum switching time, as well as to achieve uniform heating across the apertures. The effectiveness of the proposed applicator has been demonstrated by in-vitro heating experiments on the pork muscle, which showed 210.6- mm3 heating volume using only 1.4 W of on-board source power. The entire applicator was realized in a small form factor (5 mm times 50 mm times 0.524 mm) for minimally invasive interstitial insertion. The cost of the hyperthermia system can be drastically reduced by integrating active components on the applicator platform.

In this article, we extend the simulated moving bed reactor (SMBR) mode of operation to the production of propylene glycol methyl ether acetate (DOWANOL™ PMA glycol ether) through the esterification of 1-methoxy-2-propanol (DOWANOL™ PM glycol ether) and acetic acid using AMBERLYST™ 15 as a catalyst and adsorbent. In addition, for the first time, we integrate the concept of modulation of the feed concentration (ModiCon) to SMBR operation. The performance of the conventional (constant feed) and ModiCon operation modes of SMBR are analyzed and compared. The SMBR processes are designed using a model based on a multi-objective optimization approach, where a transport dispersive model with a linear driving force for the adsorption rate has been used for modeling the SMBR system. The adsorption equilibrium and kinetics parameters are estimated from the batch and single column injection experiments by the inverse method. The multiple objectives are to maximize the production rate of DOWANOL™ PMA glycol ether, maximize the conversion of the esterification reaction and minimize the consumption of DOWANOL™ PM glycol ether which also acts as the desorbent in the chromatographic separation. It is shown that ModiCon achieves a higher productivity by 12–36% over the conventional operation with higher product purity and recovery.

A new fluoro-chromogenic chemosensor based on BODIPY-functionalized gold nanoparticles 1 is prepared. Addition of Cu(2+) ions to aqueous solutions of 1 gave an instantaneous color change along with a blue-shift of the absorption band and quenching of the emission spectrum at room temperature. The chemosensor 1 exhibits a high affinity and selectivity for Cu(2+) over competing metal ions tested. Moreover, confocal microscopy experiments establish that 1 can be used for detecting Cu(2+) levels within living cells.

Introduction Nuclear and optical imaging are complementary in many aspects and there would be many advantages when optical imaging probes are prepared using radionuclides rather than classic fluorophores, and when nuclear and optical dual images are obtained using single imaging probe. Methods The luminescence intensities of various radionuclides having different decay modes have been assayed using luminescence imaging and in vitro luminometer. Radioiodinated Herceptin was injected into a tumor-bearing mouse, and luminescence and microPET images were obtained. The plant dipped in [ 32 P]phosphate solution was scanned in luminescence mode. Radio-TLC plate was also imaged in the same imaging mode. Results Radionuclides emitting high energy β + /β − particles showed higher luminescence signals. NIH3T6.7 tumors were detected in both optical and nuclear imaging. The uptake of [ 32 P]phosphate in plant was easily followed by luminescence imaging. Radio-TLC plate was visualized and radiochemical purity was quantified using luminescence imaging. Conclusion Many radionuclides with high energetic β + or β − particles during decay were found to be imaged in luminescence mode due mainly to Cerenkov radiation. ‘Cerenkov imaging’ provides a new optical imaging platform and an invaluable bridge between optical and nuclear imaging. New optical imaging probes could be easily prepared using well-established radioiodination methods. Cerenkov imaging will have more applications in the research field of plant science and autoradiography.

A bi-directional planar coaxial applicator with multiple apertures is presented in this paper. The applicator is optimized for uniform thermal distribution over large volume for low-power microwave hyperthermia. The proposed applicator can radiate microwaves in both up and down directions simultaneously, resulting in extended treatment volume. The power distribution into each aperture has been optimized to achieve uniform thermal profile by solving the bioheat equation. 3-D thermal profiles are measured on the surface of 4 mm-thick pork muscle using Infra-Red microscope from three orthogonal directions. The measured thermal profile confirms uniform thermal distribution and expanded heating volume.

In this study, the performance characteristics of electro-cyclone with different inlet shapes, such as helical, tangential and involute, were experimentally investigated. The range of particle size has 0.3 to 6 μm and the inlet velocities are 10, 15, 20, and 25 m/s. Particles used in this experiment are JIS Class 11 test powder which have the density of 1.9~2.1 g/cm3 and the mass median diameter of 2.3 μm. An electrocyclone has discharge wire which was inserted in the middle of vortex-finder. The length, diameter and material of discharge wire have 20 mm, 0.6 mm and SUS304, respectively. The discharge wire was applied with a voltage of 10 kV. The collection efficiency is calculated by the particle size distribution of the upstream and downstream using a laser optical particle counter. Pressure drops were measured between two pressure taps which were located at the inlet and outlet ducts of electrocyclone using a micromanometer. For the case of the involute type, due to a minimum turbulence, the retention time of particles becomes long in electrocyclone and particles have more chances to be charged. However, the experimental results show that a helical shape has a better collection effect than the other shapes. And the pressure drop of the involute shape for a given inlet velocity is smaller than the other shapes. The collection efficiency and the pressure drop with various inlet shapes and velocity changes in electrocyclone are graphically depicted.Copyright © 2005 by ASME