SAS Method Research Articles

Supercritical Fluid Media in Challenges of Substance and Material Dispersion

The paper deals with the problem of material dispersion using supercritical fluid media. At the same time, emphasis is made on modifications (SAS, GAS, SEDS and ASES) of the supercritical fluid anti-solvent method of dispersion. The results of SAS method implementation for dispersion of pure polycarbonate and polycarbonate doped with “CdSe/CdS - core/shell” quantum dots (carried out in the pressure range of 8.0-25.0 MPa at temperatures of 313.15 K and 358.15 K) are submitted. The range of the operating parameters has been established through the example of pure polycarbonate dispersion, which provides the production of nanoparticles with the size range of 10 100 nm. Encapsulation of CdSe/CdS quantum dots into polycarbonate using the SAS method has no effect on optical properties of the encapsulated quantum dots. The results of paracetamol dispersion using the SEDS method are presented. The effect of operating conditions of the paracetamol dispersion process on morphology of the obtained product is described. Co-dispersion of ethylene–vinyl acetate copolymers and low-density polyethylene mixtures by SEDS method has been carried out under pressures of 8.0-25.0 MPa at temperatures of 313 K, 323 K, and 333 K. The comparison of melting and crystallization between the resulting copolymer mixtures and mixtures with the same composition obtained by mixing in the liquid melt, has shown that implementation of SEDS results in an increase of crystallinity degree of the polymer mixtures.

EFEKTIVITAS METODE SAS (STRUKTUR ANALITIK SINTETIK) DALAM MENINGKATKAN KETERAMPILAN MEMBACA BAGI ANAK LAMBAT BELAJAR (SLOW LEARNER) DI SDN DEMANGAN

Abstract. This research aims to know the effectiveness of the SAS method (Structure Analytic Synthetic) for improving the reading skills to slow learner children in SDN Demangan. The subject were 8 slow learner student, who were divided into two groups, 4 student in experimenal group and 4 student in control group. The characteristics subjects in this research was slow learner children and indicated a low reading skills. The hypothesis of this research was SAS method effective in improving reading skills for slow learner studentin SDN Demangan. This research was a pure experiment research with randomized pretest-posttest control group design or using two independent groups with pretest-postets design. Mann Whitney U and Wilcoxon were used as data analisys technique. The result of Wilcoxon analysis, between the scores of pretest and posttest in experimental group is p = 0,011 (p < 0.05). These results indicated that there was differencess between the scores before and after in reading skills of group experiments. The results of Mann Whitney U analysis between a score of posttest control group and the experimental value obtained p = 0.019 (p < 0.05). These results indicated that there was a difference reading skills between the control group and experimental group. So it can be concluded that the SAS method is effective for improving the reading skills at subjects in this research.

An Improved Scale-Adaptive Simulation Model for Massively Separated Flows

A new hybrid modelling method termed improved scale-adaptive simulation (ISAS) is proposed by introducing the von Karman operator into the dissipation term of the turbulence scale equation, proper derivation as well as constant calibration of which is presented, and the typical circular cylinder flow at Re = 3900 is selected for validation. As expected, the proposed ISAS approach with the concept of scale-adaptive appears more efficient than the original SAS method in obtaining a convergent resolution, meanwhile, comparable with DES in visually capturing the fine-scale unsteadiness. Furthermore, the grid sensitivity issue of DES is encouragingly remedied benefiting from the local-adjusted limiter. The ISAS simulation turns out to attractively represent the development of the shear layers and the flow profiles of the recirculation region, and thus, the focused statistical quantities such as the recirculation length and drag coefficient are closer to the available measurements than DES and SAS outputs. In general, the new modelling method, combining the features of DES and SAS concepts, is capable to simulate turbulent structures down to the grid limit in a simple and effective way, which is practically valuable for engineering flows.

Strong sampling surfaces formulation for layered shells

The strong SaS formulation for the three-dimensional (3D) stress analysis of layered shells is based on a new concept of SaS located at Chebyshev polynomial nodes throughout the layers and integration of the equilibrium equations of elasticity. The idea of the SaS method consists in choosing the arbitrary number of SaS parallel to the middle surface in order to introduce the displacements of these surfaces as basic shell unknowns. Such choice of unknowns with the use of the Lagrange polynomials in assumed approximations of displacements and strains through the layer thicknesses leads to a compact form of the layered shell formulation. The feature of the proposed approach is that all SaS are located inside the layers at Chebyshev polynomial nodes. The use of interfaces is avoided that makes possible to minimize uniformly the error due to the Lagrange interpolation. Therefore, the strong SaS formulation can be applied efficiently to the 3D analysis of layered composite shells.

Pharmaceutical co-crystals of the anti-inflammatory drug diflunisal and nicotinamide obtained using supercritical CO2 as an antisolvent

A method based on using supercritical CO2 as an antisolvent (SAS method) is explored as a co-crystallization technique. Co-crystallization is an emerging and powerful technique to improve the physicochemical properties of an active pharmaceutical ingredient. The solid-state and solution co-crystallization methods usually employed present several disadvantages. The one-step SAS method has a low environmental impact and overcomes some of the difficulties associated to conventional methods. The 2:1 co-crystals of the anti-inflammatory drug diflunisal (DIF) and nicotinamide (NIC) are prepared for the first time by SAS. Drug concentrations corresponding to the co-crystal stoichiometric composition are used. The influence of the SAS parameters temperature (35 and 40°C), pressure (10.0 and 12.0MPa), drug concentration (two levels) and solvent (acetone and ethanol) in the co-crystal formation is studied. A crystalline material in the form of needles of uniform width and more variable length is obtained. For comparison purposes, pure DIF and NIC are also processed by SAS. Co-crystals are characterized in terms of crystallinity, thermal behavior, coformer interactions and drug release; their dissolution rate improves with respect to that of pure DIF. SAS co-crystals exhibit the same crystal structure, melting point and FTIR spectrum as those previously obtained by liquid assisted ball mill grinding and solution crystallization.

RHX Dating of Archeological Ceramics Via a New Method to Determine Effective Lifetime Temperature

Determining the absolute chronology of ceramic artifacts has significant implications for archeological and historical research. Wilson, Hall et al. recently suggested a new technique for direct absolute dating of archeological ceramics based on a moisture‐induced chemical reaction, called rehydroxylation (RHX) dating. RHX dating proceeds by measuring the mass of chemically combined water in the ceramics in the form of OH hydroxyls, and the mass gain rate at the Effective Lifetime Temperature (ELT) that the ceramics experienced over its lifetime. To date, ELT determinations have been based on estimates of the ceramic's lifetime temperature history; taking into account weather and climate data and the depth at which the artifact was found. The uncertainty in determining the ELT can be a major component of the overall dating uncertainty. Here, we propose an alternative method which relies minimally on weather and climate data, and provides more precise determinations of the ELT and the ceramic age. The proposed method (SAS: Same Age Samples) involves a minimum of four measurements of the RHX mass gain rate constant for two ceramic samples of the same age at two temperatures. We show via simulations that the proposed SAS method can determine the ELT with a precision of 0.2 K which is comparable to the best ELT determination based on lifetime temperature history, and also comparable to available microbalance temperature resolutions of around 0.1 K. The corresponding percent age error is then 1.4%, or 43 yr for a 3000‐yr‐old ceramic. The proposed SAS method should be tested with ceramic samples of different ages, whose ELT are well‐known.

MENINGKATKAN KEMAMPUAN MENARI TARI BALANSE MADAM MELALUI METODE SAS UNTUK ANAK TUNARUNGU (Single Subject Research Kelas II SMP di SLB Bundo Kanduang Padang)

Abstrack: This study aims to test the effectiveness of the use of SAS methods in studyng dancing skills for children of dance of balanse madam in SLB Bundo Kanduang Padang. This research was using Single Subject Research approach wit AB design . Subjects were a deaf children in class II SMPLB . To measure the research variables, the percentage of the techniques applied. Based on the results of data analysis, it was found that the use of SAS method effective to improve dancing skills of balanse madam in class II SMP SLB Bundo Kanduang Padang. Kata-kata kunci: Metode SAS; Menari; Tari Balanse Madam; Tunarungu

Supercritical fluid micronization of risperidone pharmaceutical substance

A comparative study of the supercritical fluid micronization of risperidone pharmaceutical substance with an initial particle size of 50 to 100 μm by the RESS and SAS methods aimed at increasing the bioavailability of risperidone as a drug was performed. Both methods makes it possible to prepare risperidone particle of various forms, 5–20 μm in size. However, the SAS method is preferable, because in contrast to RESS, it does not cause contamination of risperidone with organic solvents used in both processes or any other impurities and also makes it possible to vary the shape and size of particles. It is shown that, during SAS micronization, the polymorphic form of risperidone changes from triclinic to monoclinic.

Statistical optimization of supercritical carbon dioxide antisolvent process for preparation of HMX nanoparticles

Taguchi robust design was employed as a statistical optimization method to optimize parameters of SAS process in order to prepare HMX nanoparticles. The current application of the Taguchi statistical optimization was highly efficient in optimizing of experimental variables which are effective in HMX particle size produced by the SAS technique. The effect of operation conditions such as: pressure, temperature, HMX concentration, solution flow rate, solvent identification, and flow rate of CO2 on the size of micronized HMX particles under various levels was investigated. The effects of these variables on the particle size of produced HMX were quantitatively evaluated by the analysis of variance (ANOVA). The results showed that the size of HMX particles prepared by SAS technique could be tuned effectively by controlling the main parameters under their optimum level. Finally, the optimum conditions for preparation of HMX nanoparticles via SAS method were proposed. The results of ANOVA showed that 3.5mol/l HMX concentration, 3ml/min solution flow rate, cyclohexanone as solvent, and 70ml/min flow rate of CO2 are optimum conditions for producing HMX nanoparticles. Experimental observations showed that under optimum conditions of SAS process, the particle size of produced HMX is about 56nm.

Investigations on the flow field in an unshrouded pump impeller geometry

Transient CFD simulations are performed to investigate the flow behaviour inside an unshrouded pump using the SAS method. Two blade designs are compared at two different tip clearances and the results are validated by measurements. The detected vortex structure is visualized by the normalized helicity, further discussed regarding its development and behaviour and finally implicated to the efficiency of the two different blade designs.

Thermodynamic principles of the dispersion of polycarbonate by the SAS method

Experimental results on the phase equilibria in the dichloromethane-CO2, dichloromethanepolycarbonate, polycarbonate-CO2, and polycarbonate-dichloromethane-CO2 systems are presented. Based on these data, the parameters of the dispersion of polycarbonate by the SAS method are determined. Experimental data on the dispersion of polycarbonate by the SAS method at pressures of 8.0 to 25.0 MPa and temperatures of 313, 333, and 355 K are obtained and analyzed.

KEEFEKTIFAN METODE BILINGUAL INTENSIF UNTUK KEMAMPUAN MEMBACA DAN MENULIS PADA PENDIDIKAN KEAKSARAAN MASYARAKAT SAMIN BLORA

This research aimed to know if in Samin community reading and writing skills of literacy education participants taught with intensive bilingual method are better than those taught with SAS method. The research conducted in Tanduran Village Blora Regency in 2010, involved 40 research subjects comprising 20 subjects for experimental group with intensive bilingual method and 20 subjects with SAS method for controlling group. The data obtained were analyzed in two stages i.e. in the preliminary analysis and in hypothesis testing. The result of the research indicates, the reading and writing skills of literacy education participants in Samin community taught with intensive bilingual method are better than those taught wit SAS method.

The Scale-Adaptive Simulation Method for Unsteady Turbulent Flow Predictions. Part 2: Application to Complex Flows

The paper summarises the validation activity performed with the Scale-Adaptive Simulation turbulence model (SAS model) using the two commercial CFD solvers, ANSYS-FLUENT and ANSYS-CFX. Both the KSKL-SAS and the SST-SAS model variants have been tested, although most cases have been computed with the second. The turbulence-resolving capability of the SAS method has been validated with a representative set of test cases, covering both underlying generic flows as well as practical engineering applications. In addition to the purely aerodynamic flows with massive separation and heat transfer they include also such physical phenomena as turbulent combustion and aeroacoustics. The illustrating results show the potentials of the SAS approach for industrial flow simulations. Most of the test case simulations were conducted during the recent EU project “DESider”.

Influence of soil tillage systems on aggregate stability and the distribution of C and N in different aggregate fractions

Soil aggregation is influenced by the tillage system used, which in turn affects the amount of C and N in the different aggregate fractions. This study assessed the impact of different tillage systems on soil aggregates by measuring the aggregate stability, the organic carbon (C org) and the total nitrogen (N tot) contents within different aggregate fractions, and their release of dissolved organic carbon (DOC). Soil samples were collected from the top 0 to 10 cm of a long-term tillage experiment at Fuchsenbigl (Marchfeld, Austria) where conventional tillage (CT), reduced tillage (RT), and minimum tillage (MT) treatments were applied to a Chernozem fine sandy loam. The stable aggregates (1000–2000 μm) were subject to dispersion by the soil aggregate stability (SAS or wet sieving) method after Kemper and Rosenau (1986), and the ultrasonic method of Mayer et al. (2002). Chemical analysis of the soil was obtained for the aggregate fractions 630–1000, 250–630 and 63–250 μm gathered from the ultrasonic method. Using the SAS method, CT and RT had the least amounts of stable aggregates (18.2% and 18.9%, respectively), whereas MT had twice as much stable aggregates (37.6%). Using the ultrasonic method, MT also had the highest amount of water stable aggregates in all three fractions (1.5%, 3.7%, and 35%, respectively), followed by RT (1%, 2.3%, 32.3%), and CT (0.8%, 1.7%, 29.1%). For comparison, a reference soil, EUROSOIL 7 (ES-7) was also analysed (40%, 6.7%, and 12.1%). The highest amounts of C org and N tot were measured under MT in all three fractions, with 8.9%, 3.8%, and 1.3% for C org, and 0.4%, 0.3%, and 0.1% for N tot. Apart from the fraction 630–1000 μm, the aggregates of RT and CT contained <50% of the C org and N tot values of MT. The C/N ratio was least favourable for CT (42.6) in the aggregate fraction 630–1000 μm. The DOC release from stable aggregates after 10 min of ultrasonic dispersion was highest from MT soil (86.7 mg l −1). The values for RT and CT were 21% and 25% below this value. The results demonstrate that tillage type influences both aggregate stability and aggregate chemical composition. This research confirms that CT interferes more with the natural soil properties than RT and MT. Furthermore, MT has the highest potential to sequester C and N in this agriculturally used soil.

Sintering studies on Ni–Cu–YSZ SOFC anode cermet processed by mechanical alloying

New 40 vol%[(Cu)–Ni]–YSZ cermet materials processed by mechanical alloying (MA) of the row powders are prepared. The powder compacts are sintered in air, hydrogen and inert (argon) atmospheres at a dilatometer and tubular furnace up to 1,350 °C. Sintering by activated surface concept (SAS) can anticipate and enhance the densification in such powders. Stepwise isothermal dilatometry (SID) sintering kinetics study is performed allowing determining kinetic parameters for Ni–YSZ and Ni–Cu–YSZ pellets. Two-steps sintering processes is indicated while Cu-bearing material features the smallest activation energy for sintering. The allied MA–SAS method is a promising route to prepare SOFC fuel cell anode materials.

Peanut Core Collection Established in China and Compared with ICRISAT Mini Core Collection

The core collection has been well accepted as a useful way to improve the efficiency of crop germplasm evaluation, conservation and utilization. Around 6 390 accessions of cultivated peanut (Arachis hypogaea L.) have been collected in China. In order to characterize and utilize the germplasm more efficiently for further crop improvement, the available morphological and biochemical data were analyzed to develop a core collection. The entire collection was first stratified by botanical types and then grouped by origin locations. Based on the data of 15 morphological and biochemical characters, the accessions in each botanical type were clustered by SAS method. From each cluster, five to ten percent of the accessions were randomly selected to form a core collection consisting of 576 accessions, which was 9.01% of the entire collection. The genetic variation in the entire collec- tion was well presented in the core collection based on comparison of diversity index of the involved traits in both entire and core collections. Comparison between the newly selected Chinese peanut core collection and the introduced mini core collection con- sisting of 184 lines established at the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) indicated that there were wider diversities in the var. hirsuta and vulgaris as well as in leaf length, leaf width, seed length, seed width in the Chinese core collection. The ICRISAT peanut collection had wider diversities in var. hypogaea and fastigiata as well as in plant height and number of total branches than Chinese peanut resource.

New developments of polysaccharide synthesis via enzymatic polymerization

This review focuses on the in vitro synthesis of polysaccharides, the method of which is “enzymatic polymerization” mainly developed by our group. Polysaccharides are formed by repeated glycosylation reactions between a glycosyl donor and a glycosyl acceptor. A hydrolysis enzyme was found very efficient as catalyst, where the monomer is designed based on the new concept of a “transition-state analogue substrate” (TSAS); sugar fluoride monomers for polycondensation and sugar oxazoline monomers for ring-opening polyaddition. Enzymatic polymerization enabled the first in vitro synthesis of natural polysaccharides such as cellulose, xylan, chitin, hyaluronan and chondroitin, and also of unnatural polysaccharides such as a cellulose–chitin hybrid, a hyaluronan–chondroitin hybrid, and others. Supercatalysis of hyaluronidase was disclosed as unusual enzymatic multi-catalyst functions. Mutant enzymes were very useful for synthetic and mechanistic studies. In situ observations of enzymatic polymerization by SEM, TEM, and combined SAS methods revealed mechanisms of the polymerization and of the self-assembling of high-order molecular structure formed by elongating polysaccharide molecules.(Communicated by Hitosi NOZAKI, M.J.A.)

EGFR inhibitor gefitinib in advanced pretreated non-small cell lung cancer patients: Experience from a centre in north India

17141 Background: Gefitinib is an orally active EGFR-TKI (Epidermal Growth Factor Tyrosine Kinase Inhibitor) that demonstrated, clinically meaningful anti tumor activity, favorable toxicity profile in phase II trials involving patients with advanced pretreated NSCLC. The aim of this study was to assess the antitumour activity (time to disease progression) and toxicity profile of Gefitinib. Methods: Twenty five patients of NSCLC advanced were included in this study who have failed at least one chemotherapy regimen and completed at least one month Gefitinib (250 mg/day) therapy. The study included 18 male and 7 female patients with, a median age of 60 years (32–80 years) and performance status ECOG 0-I 64%. The histologically included were Adenocarcinoma 56%, Squamous Cell Carcinoma 40% and Large Cell Carcinoma 1%. 64% patients had failed to response to 1 (CT) chemotherapy regimen, 28% to 2 CT and 8% to 3 CT regimens. Results: A total of 25 patients (18 male, 7 female) were evaluated for response. 2 Complete Response (CR) and 1 Partial Response (PR) were observed with an Overall Response Rate (ORR) of 12% (CR+PR). All the three patients were with Adenocarcinoma histology. A total of 14 patients (56%) had Stable Disease (SD). This led to an Overall Disease Control Rate (CR+PR+SD) of 68% (17 patients). The Median Time to Progression (TTP) was 3.8 months using the SAS method for statistical analysis (95% CI 4.4–9.3). The number of previous chemotherapy regimens did not alter the response to therapy. All the patients were evaluated for toxicity profile assessment (25 patients). The most frequent toxicity observed was Asthenia in 52% of patients. Other toxicities were Diarrhaea 24%, Skin Disorders 32%, Anorexia 32%, Vomitings 44%. Only 1 patient had grade IV skin related toxicity. No deaths related to Gefitinib treatment were reported. Conclusion: Gefitinib shows antitumour activity in pretreated patients of advanced NSCLC. Gefitinib therapy of (250 mg/day) has a favourable toxicity profile and is well tolerated. Gefitinib is a viable therapy in NSCLC patients who have limited treatment options. No significant financial relationships to disclose.

Oligosaccharide Synthesis by Affinity Separation Based on Molecular Recognition Between Podand Ether and Ammonium Ion.

We previously reported a new synthetic methodology termed 'synthesis based on affinity separation' (SAS) in which the desired tagged compound was separated from the reaction mixture by solid-phase extraction using specific molecular recognition of the tag. The interaction between a crown ether tag and polymer-supported ammonium ion was initially employed for SAS. In the present study, a new SAS method using a podand-type tag, a pseudo-benzo-31-crown-10 structure, was elaborated for oligosaccharide synthesis. The podand tag was much easier to synthesize than the corresponding crown ether. The podand moiety was attached to the monosaccharide residue via appropriate linkers. After glycosylation of the tagged monosaccharide with a glycosyl donor, the reaction mixture was subjected to the affinity separation. The desired compounds possessing the podand tag were effectively separated by the affinity between the podand and the ammonium ion. Continuous flow synthesis by integration of a microreactor and the present SAS system was applied for high throughput oligosaccharide synthesis.

Profiling the autoantibody repertoire by serological antigen selection

The identification of disease related autoantigens targeted by pathogenic T- and B-cell responses is crucial for the development of improved therapies for autoimmune diseases. To identify immunogenic targets recognized by the humoral immune response, we have recently applied a novel and powerful molecular approach, named ‘serological antigen selection’ (SAS). This method involves the display of a cDNA expression library on filamentous phage and subsequent selection on patient immunoglobulin G (IgG). In the present study, we have cloned a cDNA repertoire from a multiple sclerosis (MS) patient in pVI phage display vectors and performed selections on pooled MS cerebrospinal fluid (CSF) samples immobilized with anti-human IgG. To further streamline this procedure, we report an optimized SAS procedure in which we have successfully established methods for enrichment of MS-specific candidate antigens. In conclusion, the broad applicability of the SAS method makes it a highly promising method for investigating the autoimmune repertoire.