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To elevate our understanding of ion specific activity in biological systems, the potential of mean force approach was utilized to study solvent effects on interactions between two alkali cations (Na+ and K+) with a formate anion in water. A very complex free energy landscape was observed, much more so than alkali-halide ion pairs. Furthermore, stronger binding between the Na+-formate pair was found in comparison to the K+-formate pair in water, a finding that agrees with experimental and theoretical studies of these systems. The kinetics of ion-pair interconversions were studied using transition rate theory, along with a variety of theoretical approaches such as the Kramers and Grote Hynes theories. These rate results were used to predict solvent effects on dynamical features of contact ion-pair association, in which faster dynamics were found for K+-formate pairs than for Na+-formate pairs. This work was supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences (BES), Division of Chemical Sciences, Geosciences and Biosciences. Pacific Northwest National Laboratory is a multiprogram national laboratory operated for DOE by Battelle.

We present an application of kinetic Monte Carlo (kMC) in the canonical ensemble to a calculation of vapour liquid equilibrium and to describe the adsorption of argon on a flat graphite surface and in a slit-like graphitic pore. Simulations at 77 and 87.3 K accurately describe the experimental data. The kMC method is simple to implement and, unlike conventional Monte Carlo, no rejection trials are necessary. The only move is a uniform sampling of the volume space, which makes the determination of the chemical potential straightforward using real particles in the simulation, in the same spirit as the Widom inverse potential distribution. This avoids the need to freeze the real particles before the trial insertion of test particles as is necessary in other methods, such as the Widom method and its variants.

The principal objective of this research was to determine the effects of a binder and sweeteners on the production of effervescent artichoke tea tablets from dried artichoke (Cynara scolymus L.). The recommended ratios of glycerin, sucrose and aspartame to total weight of artichoke powder and effervescent agent for production of effervescent artichoke tea tablets were 2.5, 20 and 0.6%, respectively. The effervescent artichoke tea tablets were 20 mm in diameter and 6–7 mm in height. The tablets were dried by infrared radiation at 40C air temperature and 30% air relative humidity for 18 h, and the final moisture of the tablets was 11–13%. The effervescent artichoke tea tablets were packaged in a three-layer package (polyethylene–aluminum–polyethylene) with a vacuum degree of 30%, sealing time of 3.5 s. Before use, each tablet was dissolved in 150 mL pure water at 90C. Practical Applications Effervescent tablet has some remarkable advantages such as being easy and convenient to package, transport and use. Artichoke is as herbal tea that which has prominent health benefits like reducing cholesterol and urea in blood, increasing bile secretion, diuretic, etc. Therefore, in this research, we have developed a new product from artichoke to make effervescent tea tablets.

The Extended Hierarchical State Transition Matrix (EHSTM) is a table-based modeling language frequently used in industry for specifying behaviors of a system. However, assuring correctness, i.e., having a design satisfy certain desired properties, is a non-trivial task. To address this problem, a model checker dedicated to EHSTMs called Garakabu2 is developed. However, there is no formal justification of Garakabu2, since its semantics has never been fully formalized. In this paper, we give a formal semantics to EHSTM by translating it into CSP, Communicating Sequential Processes. Our semantics covers most of the features supported by Garakabu2. We manually translate the small examples of EHSTM to CSP, and verify them by PAT, a CSP based model checker. We also verify the examples directly using Garakabu2 and show the result are same. The experiments also show that verification using our translation and PAT is much faster than that of Garakabu2 for checking message type EHSTM.

With the continuous and outstanding development of information technology(IT), human being is coming to the new computing era which is called cloud computing. This era brings lots of huge benefits also at the same time release the resources of IT infrastructure and data boom for man. In the future no longer, most of IT service providers, enterprises, organizations and systems will adopt this new computing model. There are three main deployment models in cloud computing including public cloud, private cloud and hybrid cloud; each one also has its own cons and pros. While implementing any kind of cloud services, customers have to choose one of three above deployment models. Thus, our paper aims to represent a practical framework to help the adopter select which one will be the best suitable deployment model for their requirements by evaluating each model comprehensively. The framework is built by applying the analytic hierarchy process(AHP), namely benefit-cost-opportunity-risk(BCOR) model as a powerful and effective tool to serve the problem. The gained results hope not only to provide useful information for the readers but also to contribute valuable knowledge to this new area. In addition, it might support the practitioners` effective decision making process in case they meet the same issue and have a positive influence on the increase of right decision for the organization.

Accessible volume, geometrical area and accessible pore size distribution are the fundamental structural parameters in the characterization of porous solids. We provide a novel “inverse” procedure, which is based on the mass balance and an MC optimization scheme, to determine these parameters from the analysis of experimental adsorption isotherms for a number of commonly used activated carbons: BPL, AX-21 and Norit. Our results, based on a kernel of model pores generated from GCMC simulations, are compared with, and shown to be different from, the results obtained from the conventional method. We show that the discrepancies arise from an incorrect evaluation of both micropore and mesopore sizes.

A number of measures are proposed as a microscopic means to analyse adsorption of gas on a surface and in slit pores under subcritical and supercritical conditions. Layer fluctuation of particle number provides us with information on where most of the mass interchange occurs, which can then be used as an indicator of the position of the interface separating the adsorbed phase and gas phase. The layer compressibility can be used to compare the adsorbed phase density with that of the bulk liquid. The layer isosteric heat provides an indication of the relative contribution of each layer to the overall isosteric heat. Finally, a histogram of particle number as a function of fluid–fluid particle energy is utilised to yield valuable information about the energetic structure of the adsorbed phase, for example (1) the number of neighbouring particles and (2) the evolution of the arrangement of particles.

A new and simple method to determine equilibrium phase transition in adsorption systems exhibiting a hysteresis loop is presented as an alternative to methods such as multiple histogram reweighting, gauge cell method and thermodynamic integration. This method is based on the NVT-grand canonical Monte Carlo mid-density scheme to determine the coexistence chemical potential and coexistence densities of an adsorption system. We illustrate this new scheme with argon and methane adsorption in a number of model solids having slit and cylindrical pores. This method does not have a strong basis on thermodynamic ground, but it does provide a simple heuristic approach that is simpler to understand physically.

We report a computer simulation and experimental study of adsorption of methanol on a highly graphitized thermal carbon black over a range of temperatures to investigate the adsorptive capacity, the isosteric heat, and the configuration of molecules in the adsorbed layer. We include coverage beyond the monolayer region, not previously studied in detail. The adsorption is shown to be strongly affected by hydrogen bonding which results in strong fluid-fluid interaction between the adsorbed molecules. The adsorption isotherms are initially sigmoidal, however, and in the multilayer region the isotherms follow typical type II behavior. The isosteric heat of adsorption of methanol is distinctly different from that of simple gases because of the dominance of the strong interactions between adsorbed molecules over the solid-fluid interactions. The configuration of adsorbed molecules in the submonolayer region favors the formation of 2D cyclic clusters of four or five methanol molecules, which maximizes the hydrogen bonding, while near the end of the completion of the first layer methanol molecules form molecular chains with some degree of 2D-zigzag pattern which again maximizes the hydrogen bonding between all molecules. This is in qualitative agreement with the X-ray diffraction measurements obtained by Morishige (Morishige, K.; Kawamura, K.; Kose, A. J. Chem. Phys. 1990, 93, 5267). When the second and higher layers are formed above the surface, the adsorbate forms clusters in three-dimensional configurations; however, the molecular chains with some degree of 2D-zigzag pattern in the first layer still remain.

The isosteric heat versus loading of simple fluids (noble gases and nitrogen) adsorbed on a graphitic surface at a range of temperatures is investigated with GCMC simulations. At low temperatures (usually below the bulk triple point) the adsorption isotherms show a distinct 2D-phase transition in the first layer and possibly in higher layers and then has a more complex pattern. For densities less than the gaseous 2D-density, the heat increases linearly with loading. For loadings across the 2D-transition, the isosteric heat is constant, and when loadings are greater than the "liquid-like" density of the 2D-transition the isosteric heat again increases linearly with loading up to monolayer concentration, beyond which the isosteric heat decreases sharply, indicating the onset of adsorption into the second layer. Grand canonical Monte Carlo simulation shows that the constant heat observed in the 2D-transition is because of the increase in the number of clusters of similar size, rather than the increase in the cluster size. At very low temperature, a dense layer forms before the onset of the next layer and there is no heat spike in the plot of the isosteric heat versus loading because there are no gaps large enough in the dense layer for further addition of a particle. Moreover, there is no heat spike in these plots at high temperatures because of the increase in thermal motion of the molecules. Therefore, there is a narrow range of temperature from which we can see an isosteric heat spike, resulting from the squeezing of molecules into the lower layers, which increases both the solid-fluid interaction and the fluid-fluid interaction. We have found that the 2D-critical temperatures of the first three layers correlate well with the well depth of the fluid-fluid interaction, and interestingly the 2D-critical temperature of the third layer is between those of the first and second layers. © 2010 American Chemical Society.

Background: Phyllanthus amarus (P. amarus) has been used as a medicinal plant for the prevention and treatment of chronic ailments such as diabetes, hepatitis, and cancer. Methods: The physicochemical properties, antioxidant and cytotoxic activities of crude extracts and fractions from P. amarus were determined using spectrophotometric method. Results: The P. amarus methanol (PAM) extract had lower levels of residual moisture (7.40%) and water activity (0.24) and higher contents of saponins, phenolics, flavonoids, and proanthocyanidins (1657.86 mg escin equivalents, 250.45 mg gallic acid equivalents, 274.73 mg rutin equivalents and 61.22 mg catechin equivalents per g dried extract, respectively) than those of the P. amarus water (PAW) extract. The antioxidant activity of PAM extract was significantly higher (p < 0.05) than that of the PAW extract, PAM fractions, and phyllanthin (known as a major compound in the P. amarus). Higher cytotoxic activity of PAM extract based on MTT assay on different cell lines including MiaPaCa-2 (pancreas), HT29 (colon), A2780 (ovarian), H460 (lung), A431 (skin), Du145 (prostate), BE2-C (neuroblastoma), MCF-7 (breast), MCF-10A (normal breast), and U87, SJ-G2, SMA (glioblastoma) was observed in comparison to the PAW extract and PAM fractions. The cytotoxic potential of the PAW extract (200 μg/mL), based on the CCK-8 assay on a pancreatic cancer cell line (MiaCaPa2) was significantly lower (p < 0.05) than those of gemcitabine (50 nM) and a saponin-enriched extract from quillajia bark at 200 μg/mL (a commercial product), but was significantly higher than that of phyllanthin at 2 μg/mL. Conclusions: The results achieved from this study reveal that the PA extracts are a potential source for the development of natural antioxidant products and/or novel anticancer drugs.

Xao tam phan (P. trimera) has been used for the treatment of cancer and cancer-like aliments. Among different parts of P. trimera plant, leaf is considered as a residual part after harvesting of the root. This study aimed to determine the physiochemical properties, antioxidant and anti-proliferative capacities of P. trimera leaf (PTL) using microwave drying for the preparation of dry sample; methanol and microwave-assisted extraction for the preparation of crude extract; and freeze drying for the preparation of powdered extract. The results showed that total phenolic, total flavonoid, proanthocyanidin and saponin contents of PTL prepared by microwave drying at 450 W were 25.4 mg gallic acid equivalents (GAE), 86.3 mg rutin equivalents (RE), 5.6 mg catechin equivalents (CE), and 702.1 mg escin equivalents (EE) per g dried sample, respectively. Gallic acid, protocatechuic acid, ellagic acid, rutin, and quercetin were identified in the PTL methanolic extract. Dried PTL displayed potent antioxidant activity, while the powdered PTL extract exhibited great anti-proliferative capacity on various cancer cell lines including MiaPaCa-2 (pancreas), HT29 (colon), A2780 (ovarian), H460 (lung), A431 (skin), Du145 (prostate), BE2-C (neuroblastoma), MCF-7 (breast), MCF-10A (normal breast), and U87, SJ-G2 and SMA (glioblastoma). Anti-proliferative capacity on pancreatic cancer cells (MiaCaPa2, BxPc3, and CFPAC1) of PTL extract (200 μg/mL) was significantly higher (P < 0.05) than those of ostruthin (20 μg/mL) and gemcitabine (50 nM), and to be comparable to the powdered P. trimera root extract and a saponin-enriched extract from quillajia bark (a commercial product). The findings from this study allow us to conclude that the PTL is a rich source of phytochemicals that possess promising antioxidant and anti-proliferative activities, therefore it shows potential as lead compounds for application in the nutraceutical, medicinal and pharmaceutical industries. This article is protected by copyright. All rights reserved.

Euphorbia tirucalli (E. tirucalli) is now widely distributed around the world and is well known as a source of traditional medicine in many countries. This study aimed to utilise response surface methodology (RSM) to optimise ultrasonic-assisted extraction (UAE) conditions for total phenolic compounds (TPC) and antioxidant capacity from E. tirucalli leaf. The results showed that ultrasonic temperature, time and power effected TPC and antioxidant capacity; however, the effects varied. Ultrasonic power had the strongest influence on TPC; whereas ultrasonic temperature had the greatest impact on antioxidant capacity. Ultrasonic time had the least impact on both TPC and antioxidant capacity. The optimum UAE conditions were determined to be 50 °C, 90 min. and 200 W. Under these conditions, the E. tirucalli leaf extract yielded 2.93 mg GAE/g FW of TPC and exhibited potent antioxidant capacity. These conditions can be utilised for further isolation and purification of phenolic compounds from E. tirucalli leaf.

In our previous work [17], we proposed a model-based combinatorial testing method, called FOT. It provides a technique to design test-models for combinatorial testing based on extended logic trees. In this paper, we introduce pair-wise testing (and by extension, n-wise testing, where n = 1, 2, ...) to FOT, by developing a technique to construct a test-suite of n-wise strategies from the test models in FOT. We take a "transformation approach" to realize this technique. To construct test suites, this approach first transforms test-models in FOT, represented as extended logic trees, to those in the formats which the existing n-wise testing tools (such as PICT [9], ACTS [30], CIT-BACH [31], etc.) accept to input, and then applies transformed test-models to any of these tools. In this transformation approach, an algorithm, called "flattening algorithm", plays a key role. We prove the correctness of the algorithm, and implement the algorithm to automate such test-suite constructions, providing a tool called FOT-nw (FOT with n-wise). Further, to show the effectiveness of the technique, we conduct a case study, where we apply FOT-nw to design test models and automatically construct test suites of n-wise strategies for an embedded system of stationary services for real-use in industry.

The aim of this study was to determine the mass proportion of carrot root and the effects of four various solvents (methanol, water, ethanol and hexane) on the contents of total phenolics and saponins as well as antioxidant capacity of carrot peel to identify an optimal solvent for effective extraction of bioactive compounds from carrot peel for further investigation. The results showed that carrot root consisted of body, heads and peel with their mass proportion of 83.19%, 5.01% and 14.19% by fresh weight, respectively. Among four solvents tested, methanol obtained the highest levels of extraction yield (54.02% by dry weight), total phenolic content (9.02 mg GAE/g dry weight) and antioxidant capacity (DPPH radical scavenging capacity, cupric ion reducing antioxidant capacity, and ferric reducing antioxidant power) from carrot peel, while water extracted the highest content of saponins (272.9 mg EE/g dry weight) and possessed the maximum ABTS radical scavenging capacity. Therefore, methanol and water are considered for effective extraction of phenolics and saponins from carrot peel, respectively. The phenolic/saponin-enriched extracts are potential sources for further applications in the healthy food and/or pharmaceutical industries.

Different parts of Helicteres hirsuta Lour. (H. hirsuta L.) have been used as traditional medicines, however limited studies have been conducted on the preparation of dried material or the extraction of bioactive compounds. This study aimed to determine the effect of various solvents and drying methods on the bioactive compound yield and antioxidant capacity of the H. hirsuta L. stem. The results showed that water was the best solvent for obtaining the highest levels of phenolics and flavonoids, whereas methanol was the solvent of choice for saponin extraction. Among assessed drying methods, hot-air drying at 80C revealed as the best method to maintain the bioactive components (phenolics of 8.99 mg GAE/g, flavonoids of 9.60 mg CE/g and saponins of 15.18 mg ESE/g), and DPPH, ABTS, and FRAP antioxidant activities. Thus hot-air drying at 80C is recommended for preparation of dried H. hirsuta L. stem for further processing steps. Practical Applications The optimal drying condition to prepare dried H. hirsuta L. stem is hot-air drying at 80C, a simple and fast drying method, and the most suitable solvent for extraction of antioxidant components from dried H. hirsuta L. stem is water; a cheap, accessible, and environmentally friendly solvent. These conditions can be applied for isolating and purifying bioactive compounds for further application in the food and pharmaceutical industries.

The aim of this study was to determine the optimal microwave-assisted extraction (MAE) parameters for saponins and antioxidant capacity from the P. trimera root. The optimal MAE parameters were found to be 100% methanol, extraction time of 40 min and ratio of solvent to sample of 100 mL/g. Saponin content, saponin extraction efficiency, ABTS radical scavenging capacity, DPPH radical scavenging capacity, cupric ion reducing antioxidant capacity, and ferric reducing antioxidant power of the P. trimera root achieved under these parameters were 520.5 mg escin equivalents (EE)/g dried sample, 62.6%, 215.3, 93.2, 24.7, 121.7 mg trolox equivalents (TE)/g dried sample, respectively, which were higher than predicted values (488.8 mg EE/g dried sample, 58.8%, 213.7, 89.5, 24.0, 115.8 mg TE/g dried sample, respectively). Therefore, the optimal MAE parameters of 100% methanol, 40 min and 100 mL/g are recommended for obtaining saponin-enriched extracts from the P. trimera root for potential application in the food industry. Practical Application This study indicated that methanol concentration had the highest effect on the extractability of saponins and antioxidant capacity from P. trimera root, followed by ratio of solvent to sample and extraction time. Therefore, the application of the optimized MAE parameters allows obtaining the highest saponin yield as well as the greatest antioxidant capacity from P. trimera root for further investigation and application.

The proximate composition of seagrape (Caulerpa lentillifera) from culture ponds in Penghu, Taiwan was analyzed. The phenolic content and the antioxidant activities including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activity, ferric ion-reducing activity, hydrogen peroxide scavenging activity, and ferrous ion chelating (FIC) activity of the ethanolic extracts of dry seagrape samples using 2 drying methods of freeze drying and thermal drying were compared with the ethanolic extract of Oolong tea as a reference. The contents (dry weight basis) of carbohydrate, crude protein, crude lipid, crude fiber, and ash of seagrape obtained from culture ponds in Taiwan were 64.00%, 9.26%, 1.57%, 2.97%, and 22.20%, respectively. The total phenolic content (1.30 mg gallic acid equivalent [GAE]/g dry weight) of the ethanolic extract of thermally dried seagrape was significantly lower (P < 0.05) than that (2.04 mg GAE/g dry weight) of freeze-dried seagrape, and both were significantly lower than that (13.58 mg GAE/g dry weight) of Oolong tea. At the same phenolic content, the antioxidant activities of freeze-dried seagrape were significantly higher (P < 0.05) than those of thermally dried seagrape. Compared with Oolong tea, seagrape, irrespective of drying method used, generally had strong hydrogen peroxide scavenging activity; but it was weak in DPPH radical scavenging activity, ferric ion-reducing activity, and FIC activity. The antioxidant activity of seagrape and Oolong tea was significantly influenced by their phenolic contents. Practical Application: The proximate composition, total phenolic content, and antioxidant activity of seagrape (Caulerpa lentillifera) in Taiwan were determined in this research to indicate nutritionally of this edible seaweed to human health, and compared these results to previous studies.

We model the volumetric method commonly used in the measurement of gas-phase adsorption isotherms by using Monte Carlo (MC) simulation to study slit pore adsorption in a finite volume. Although the method has been used for a very long time, modeling of the operation by a Monte Carlo scheme to account properly for the exchange of mass between the solid and the finite dosing volume has not been widely studied in the literature. This paper presents the MC simulation of the system composed of the solid subsystem and the gas phase surrounding it. We show that not only the size of the dosing volume and the incremental dosing amount but also the pore shape, pore size, and temperature have significant effects on the unstable region of the phase diagram, especially when the system is going through a first-order transition. This study extends and augments the recent work of Puibasset et al. (1) by showing that the shape of the adsorbent walls and the incremental dosing amount can affect the chemical potential in the adsorption system.

An investigation was carried out to determine the effects of some factors on the production of effervescent artichoke tea tablets from dried artichoke (Cynara scolymus L.): extraction solvent composition, extraction temperature, extraction time, ratios of leaf, flower, stalk and root of dried artichoke, concentration of spray-drying solution, spray-drying temperature, spray-drying carrier, concentration of spray-drying carrier, proportion of effervescent agent, and components proportion of effervescent agent. The recommended extraction solvent was water with 10 percent of ethanol 96 percent (v/v), with an extraction temperature of 100°C, soak time of 14 hours, first extraction time of one hour, second extraction time of three hours. The dried artichoke raw material consisted of 1.0 parts leaf, 0.5 parts flower, 1.0 parts stalk and 1.5 parts root. The recommended concentration of spray-drying solution was 20 percent, spray-drying temperature of 150°C, spray-drying carrier was maltodextrin at a concentration of 10 percent. The recommended effervescent agent consisted of 1.0 parts citric acid, 1.0 parts tartaric acid and 2.44 parts sodium bicarbonate, added at 45 percent of total weight of effervescent tablet.

In the roundtable that follows, clinicians discuss a study published in this issue of the Journal in light of its methodology, relevance to practice, and implications for future research. Article discussed: Maayan-Metzger A, Schushan-Eisen I, Todris L, et al. Maternal hypotension during elective cesarean section and short-term neonatal outcome. Am J Obstet Gynecol 2010;202:56.e1-5.

The article below summarizes a roundtable discussion of a study published in this issue of the Journal in light of its methodology, relevance to practice, and implications for future research. Article discussed: Maayan-Metzger A, Schushan-Eisen I, Todris L, et al. Maternal hypotension during elective cesarean section and short-term neonatal outcome. Am J Obstet Gynecol 2010;202:56.e1-5. The full discussion appears at www.AJOG.org, pages e12-e14.

We report the isolation of a cDNA clone named GPR54, which encodes a novel G protein-coupled receptor (GPCR). A PCR search of rat brain cDNA retrieved a clone partially encoding a GPCR. In a library screening this clone was used to isolate a cDNA with an open reading frame (ORF) encoding a receptor of 396 amino acids long which shared significant identities in the transmembrane regions with rat galanin receptors GalR1 (45%), GalR3 (45%) and GalR2 (44%). Northern blot and in situ hybridization analyses revealed that GPR54 is expressed in brain regions (pons, midbrain, thalamus, hypothalamus, hippocampus, amygdala, cortex, frontal cortex, and striatum) as well as peripheral regions (liver and intestine). In COS cell expression of GPR54 no specific binding was observed for 125I-galanin. A recent BLAST search with the rat GPR54 ORF nucleotide sequence recovered the human orthologue of GPR54 in a 3.5 Mb contig localized to chromosome 19p13.3.