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Intergroup conflict management strategies as related to perceptions of dual identity and separate groups.

The authors examined the relations between (a) the perceptions of dual identity and separate groups and (b) intergroup conflict management strategies, in two contexts: the conflict between the secular and religious sectors in Israel and the allocation of resources among organizational subunits. In both contexts, contention (i.e., forcing one's will on the other party) was associated with the perception of separate groups. Only in the organizational context, avoidance (i.e., doing nothing or discontinuing participation in the conflict) was associated with the perception of dual identity. Problem solving (i.e., finding a solution that is acceptable to both parties) was related to the perception of dual identity in the secular-religious context. In the organizational context, this relation appeared only under a low perception of separate groups. Yielding (i.e., satisfying the other party's needs at the expense of one's own) was related to the perception of dual identity in the organizational context. In the secular-religious context, this relation appeared only under a high perception of separate groups. The authors discussed the varying pattern of the associations between (a) the perceptions of dual identity and separate groups and (b) the conflict management strategies in the two contexts in terms of the Dual Concern Model and the perceived feasibility of the strategies.

Adult↗

Driving attention with the top down: the relative contribution of target templates to the linear separability effect in the size dimension.

Bauer, Jolicoeur, and Cowan (1996a, 1996b, 1998) have shown that visual search for a target among distractors is apparently serial if the target is nonlinearly separable from the distractors in a particular feature space (e.g., color or size). In contrast, if the target is linearly separable from the distractors, search is relatively easy and seemingly spatially parallel. We examined the contribution of top-down knowledge of the target to the linear separability effect on search. Two visual search experiments were conducted using small, medium, or large circles as targets. In the first experiment, participants could use knowledge of the target to guide search, whereas, in the second, the target was unknown on each trial. Search for a medium (nonlinearly separable) target among small or large distractors benefited least from knowledge of the target as compared with search for a small or large target. Thus, the linear separability effect can be determined in part by use of top-down knowledge to facilitate the detection of targets at the ends of a continuum defining the stimuli.

Adolescent↗

Auditory apparent motion in the free field: the effects of stimulus duration and separation.

The effects of stimulus duration and spatial separation on the illusion of apparent motion in the auditory modality were examined. Two narrow-band noise sources (40 dB, A-weighted) were presented through speakers separated in space by 2.5 degrees, 5 degrees, or 10 degrees, centered about the subject's midline. The duration of each stimulus was 5, 10, or 50 msec. On each trial, the sound pair was temporally separated by 1 of 10 interstimulus onset intervals (ISOIs): 0, 2, 4, 6, 8, 10, 15, 20, 50, or 70 msec. Five subjects were tested in nine trial block; each block represented a particular spatial-separation-duration combination. Within a trial block, each ISOI was presented 30 times each, in random order. Subjects were instructed to listen to the stimulus sequence and classify their perception of the sound into one of five categories: single sound, simultaneous sounds, continuous motion, broken motion, or successive sounds. Each subject was also required to identify the location of the first-occurring stimulus (left or right). The percentage of continuous-motion responses was significantly affected by the ISOI [F(9,36) = 5.67, p less than .001], the duration x ISOI interaction [F(18,72) = 3.54, p less than .0001], and the separation x duration x ISOI interaction [F(36,144) = 1.51, p less than .05]. The results indicate that a minimum duration is required for the perception of auditory apparent motion. Little or no motion was reported at durations of 10 msec or less. At a duration of 50 msec, motion was reported most often for ISOIs of 20-50 msec.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[Rapid determination of 137Cs in environmental samples--purification of 137Cs by ammonium molybdophosphate column separation].

A rapid method for the determination of 137Cs in environmental samples was proposed. The principal technic employed in this study is based on column separation of 137Cs using ammonium molybdophosphate mixed with glass fiber to eliminate contribution of natural radionuclides such as 40K and 87Rb. The separation of cesium from potassium and rubidium was performed by the elution with 0.5m ammonium nitrate solution. The time required for separation of cesium was five hours as compared with the conventional cation exchange separation which required thirteen hours. The chemical yield of cesium carrier was normally more than 90 percent. The results obtained were compared with that by the conventional methods using Bio-Rex cation exchange separation and the good agreement between the two methods was obtained.

Animals↗

Effect of experimental fluoride-releasing tooth separator on acid resistance of human enamel in vitro.

This study aimed to investigate the fluoride-releasing ability of an experimental tooth separator consisting of polyurethane elastomer with tin fluoride and its effect on the acid resistance of human enamel. The tooth separator was set around an enamel slab and stored in de-ionized water for 10 days. The daily concentration of fluoride in the de-ionized water was measured. Then the enamel surface was artificially decalcified by a lactic acid buffer solution (pH 4.5) for 96 hours. The mineral density at the surface layer of the enamel was measured to evaluate the acid resistance. The fluoride release increased with the amount of fluoride in the separator, but decreased with the immersion time. Both the enamel area contacting with the separator and its surrounding area showed lower mineral loss and lesion depth compared with the controls (P < 0.05). It is suggested that the experimental tooth separator would release enough fluoride and improve the acid resistance of the enamel surface layer.

Absorptiometry, Photon↗

Methods for rapid separation and concentration of bacteria in food that bypass time-consuming cultural enrichment.

The rapid detection of pathogenic organisms that cause foodborne illnesses is needed to insure food safety. Conventional methods for the detection of pathogens in foods are time-consuming and labor-intensive. New advanced rapid methods (i.e., polymerase chain reaction, DNA probes) are more sensitive and selective than conventional techniques, but many of these tests are inhibited by food components, rendering them dependent on slow cultural enrichment. The need for alternative methods that will rapidly separate and concentrate bacteria directly from food samples, thereby reducing the time required for these new rapid detection techniques, is evident. Separation and concentration methods extract target bacteria from interfering food components and/or concentrate bacteria to detectable levels. This review describes several methods used to separate and/or concentrate bacteria in food samples. Several methods discussed here, including centrifugation and immunomagnetic separation, have been successfully used, individually and in combination, to rapidly separate and/or concentrate bacteria from food samples in less time than is required for cultural enrichment.

Bacteria↗

Separated chorioamnion and elevated chorion: sonographic features and clinical significance.

The clinical presentation and outcome of pregnancy was analyzed in thirteen patients in whom a free-floating intrauterine membrane was found on sonography. The cases were divided into two groups: those with elevated chorion and those with chorioamniotic separation. Five of seven patients with chorioamniotic separation progressed normally to term and delivered normal infants. In the two pregnancies with chorioamniotic separation that did not progress to term, one was associated with a placental chorioangioma and the other had a dead fetus that had a cystic hygroma indicative of Turner's syndrome. Of the six patients with elevated chorion, all presented with an episode of vaginal bleeding in the early second trimester. Five of six patients with elevated chorion progressed to term with the delivery of normal infants. One patient with extensive elevation of the chorion aborted. Three patients with elevated chorion had a subchorionic clot, whereas this was not present in patients with separated chorioamnion. Follow-up sonographic examination of patients with separated chorioamnion and elevated chorion revealed that most (11 of 13), but not all pregnancies in which an intrauterine membrane was found progressed to term without complications.

Abortion, Spontaneous↗

Can minimum separation criteria ensure electromagnetic compatibility in hospitals? An experimental study.

Electromagnetic interference (EMI) from radiofrequency (RF) sources can cause medical device malfunction. It has been proposed that such EMI be minimized by only operating sources of given RF powers when sufficiently separated from medical devices of given immunities. Such minimum separation criteria are estimated assuming free-space propagation, which is only valid in the ideal case. Yet proposed medical device EMC standards will require that minimum-separation criteria be listed in equipment manuals accompanying all new medical devices. It is essential that the practical utility of such minimum-separation criteria be evaluated. Fields due to an 800-MHz-type cellphone were measured in various rooms and corridors within an urban hospital, having both new (gyprock) and old (clay-block) wings. Data obtained from a calibrated antenna attached to a spectrum analyzer were repeatedly measured and averaged. Results were compared to those predicted by free-space propagation. Free-space predictions tended to overestimate measured fields in gyprock rooms and along corridors of both gyprock and clay-block construction. However, the free-space model tended to underestimate field levels predicted in clay-block rooms and in below-ground corridors. Usage of separation criteria to ensure EMC appeared useful in gyprock rooms and hospital corridors, but less so in rooms with clay-block walls or in below-ground sections of the hospital. This suggested that the latter regions should be considered as being special zones where side-by-side operation of RF sources and medical devices would require more conservative management (e.g., restriction or special approval of particular source or medical device).

Electric Conductivity↗

Preparative free-solution isotachophoresis for separation of human plasma lipoproteins: apolipoprotein and lipid composition of HDL subfractions.

We have previously shown that plasma lipoproteins can be separated by analytical capillary isotachophoresis (ITP) according to their electrophoretic mobility in a defined buffer system. As in lipoprotein electrophoresis, HDL show the highest mobility followed by VLDL, IDL, and LDL. Chylomicrons migrate according to their net-charge between HDL and VLDL, because ITP has negligible molecular sieve effects. Three HDL subfractions were obtained which were designated fast-, intermediate-, and slow-migrating HDL. To further characterize these HDL subfractions, a newly developed free-solution ITP (FS-ITP)-system was used, that allows micro-preparative separation of human lipoproteins directly from whole plasma (Böttcher, A. et al. 1998. Electrophoresis. 19: 1110-1116). The fractions obtained by FS-ITP were analyzed for their lipid and apolipoprotein composition and by two-dimensional nondenaturing polyacrylamide gradient gel electrophoresis (2D-GGE) with subsequent immunoblotting. fHDL are characterized by the highest proportion of esterified cholesterol of all three subfractions and are relatively enriched in LpA-I. Together with iHDL they contain the majority of plasma apoA-I, while sHDL contain the majority of plasma apoA-IV, apoD, apoE, and apoJ. Pre-beta-HDL were found in separate fractions together with triglyceride-rich fractions between sHDL and LDL. In summary, ITP can separate the bulk of HDL into lipoprotein subfractions, which differ in apolipoprotein composition and electrophoretic mobility. While analytical ITP permits rapid separation and quantitation for diagnostic purposes, FS-ITP can be used to obtain these lipoprotein subfractions on a preparative scale for functional analysis. As FS-ITP is much better suited for preparative purposes than gel electrophoresis, it represents an important novel tool for the functional analysis of lipoprotein subclasses.

Electrophoresis↗

Separation protest in day-care and home-reared infants.

Separation protest was measured by the onset and duration of fretting or crying in 24 day-care and 28 home-reared infants during a two-minute period of isolated separation from their mothers in an unfamiliar room. Separation episodes were repeated under similarly controlled circumstances at two-month intervals from 3 1/2 through 13 1/2 months and at 20 months of age. The composition of the day-care and home-reared groups was similar for sex, ordinal position, and family background. Day-care and home-reared infants showed similar patterns in the manifestation of separation protest over age, with sharp reductions in latency to crying and marked increases in the occurrence of crying at 9 1/2 and 13 1/2 months. These results suggest that the psychological processes underlying separation protest are not materially altered by the continuing presence of the young infant in a day-care program designed to meet both his physical and psychological requirements.

Age Factors↗

[The essays of Keizou Tanba and Ougai Mori about separation of dispensary from medical practice].

Keizou Tanba wrote an article on separation of dispensary in Chugai-iji-shinpo in June, the year 23 of Meji Era. It was said that separation of dispensary had to be carried out and it brought many advantages. First, a pharmacist can examine the prescription and correct it if there are any mistakes. He will be able to give an advice to a doctor that the side effects will perhaps occur due to preparation of medicine. Secondly, a pharmacist can superintend whether unnecessary medicine is prescribed or not. He will check surplus prescription in such a case that a patients will be cured by observing dietary or exercise. According to Tanba's opinion, if we will get people to know what separation of dispensary is, it is easy to be carried out. Ougai Mori wrote an essay separation of dispensary in the same period. His opinion was opposite, basically. It caused to impose a burden on a patient. As the number of pharmacist were not enough, it was impossible to carry it out. A conflict of opinion also remains among people related to medicine at present. The circumstances on separation of dispensary have not been changing during one hundred years.

Health Services↗

[Optimization of non-gel sieving capillary electrophoretic separation of DNA fragments of hundreds of base pairs].

Non-gel sieving capillary electrophoresis has been employed in the biological sciences for the size-based separation of macromolecules such as nucleic acids. In this paper, four factors i.e. electric field strength, capillary length, capillary diameter and hydroxy-propylmethylcellulose (HPMC) concentration were integratively evaluated to select the optimal condition of separating DNA fragments of a few hundreds of base pairs through orthogonal analysis. Conclusion was made through comprehensive analysis: better separation could be achieved in longer capillary, smaller inside diameter of capillary and less field strength. In practical application, effective separation in short time is important. We preferred to employ 8 g/L HPMC in coated capillary (37 cm x 75 microns i.d.) and electric field strength of 324 V/cm in separating DNA fragments of hundreds of base pairs. From sampling to getting results only a few more than ten minutes were needed in capillary electrophoresis. It needs less amount of sample (a few nanoliters) and shows higher sensitivity (0.1 pmol in UV detection) than polyacrylamide gel electrophoresis (PAGE). pBR322/Msp I fragments were completely resolved in both capillary electrophoresis and PAGE, and four-bases resolution was obtained. When the concentration of the PCR product is too low (< 20 mg/L), PCR reaction system is used as a negative control to make sure of the peak generated by the unpurified PCR products, avoiding interference made by PCR buffer and polymerase.

Apolipoprotein B-100↗

[Studies on separation and identification of Rhizoma coptidis brugs based on microemulsion thin-layer chromatography].

OBJECTIVE: To investigate the use of microemulsion TLC for the separation and identification of Rhizoma Coptidis drugs. METHOD: Thirteen Rhizoma Coptidis drugs were separated and identified with six kinds of SDS/n-C4H9OH/n-C7H16/H2O microemulsions as mobile phase on polyamide film. Effects of microemulsions on separation were investigated. RESULTS: The best mobile phase was the O/W microemulsion(containing 75% water). Compared with general mobile phases, the separation and detection could be improved and the test conditions were more tolerant. CONCLUSION: This new method is simple, accurate and efficient for the separation and identification of Rhizoma Coptidis drugs.

Berberine↗

[Separation model of small molecules with SEC columns and micellar mobile phase].

Small alkanol molecules were successfully separated with SEC method in combination with a micellar mobile phase. The separation model has been given in this system. The separation is based on the differential migration of the micelle and the surrounding water and the differential distribution of the solute between the micelle and aqueous phase, therefore, the separation mechanism is very similar to that of micella electrokinetic chromatography (MEKC). The retention volume of solute is related to the micellar concentration by theoretical treatment, through which the solute distribution coefficient between micelle and aqueous phase could be obtained. Two different SEC columns were employed for separation of some alkanols and the theoretical model is supported by the experimental results. The distribution coefficients obtained were in good agreement for these two columns.

Azo Compounds↗

[Research on the separation of limonoid glucosides by reversed-phase preparative high performance liquid chromatography].

Obacunone-17-beta-D-glucopyranoside (OG) was isolated from the seeds of Citrus Sinensis Osbeck by using solvent extraction, classical polymer adsorption column separation and weak base anion ion-exchange separation, OG was finally purified by C18 reversed-phase preparative high performance liquid chromatography and was identified by thin-layer chromatography. The purity of OG was analyzed by analytical reversed-phase HPLC. At last the structure of OG was determined by 1H and 13C nuclear magnetic resonance spectrometry (NMR). In this work, the conditions of the reversed-phase preparative HPLC technique to purify limonoid glucosides was optimized. The reversed-phase preparative HPLC on a C18 column with a mobile phase of acidic acetonitrile-water (about 0.2% TFA, V/V) at pH 3 enabled the baseline separation of limonoid glucosides in the extract. The results show that OG is the predominant limonoid glucoside in the seeds of Citrus Sinensis Osbeck and nomilin glucoside is the second one. The results also show that the classical polymer adsorption column separation and weak base anion ion-exchange separation are effective for purifying limonoid glucosides.

Chromatography, High Pressure Liquid↗

[Enantiomeric separation of N-FMOC amino acids with sulfobutyl ether-beta-cyclodextrin as chiral additive by capillary electrokinetic chromatography].

Enantiomeric separation of N-FMOC amino acids by capillary electrophoresis with an anionic chiral resolving agent, sulfobutyl ether-beta-cyclodextrin (SBE-beta-CD) with average substitution degree of 3.8, employed as chiral additive was studied. Chiral separation was achieved with the mode of electrokinetic chromatography due to the electrophoretic mobility and chiral complexing ability of the chiral additive. The effects of pH of background electrolyte, the concentration of sulfobutyl ether-beta-cyclodextrin on enantiomeric separations were investigated. The enantiomeric separations of 8 N-FMOC amino acids were accomplished, among which 5 N-FMOC amino acids could be on baseline separated.

Amino Acids↗

[Separation of DNA fragments from halobacterium halobium by capillary electrophoresis with non-gel sieving media].

The optimum electrophoresis separation conditions of Lambda DNA/EcoR I + Hind III fragments were investigated using the capillary column DB-1 coated with polysiloxane. When hydroxyethylcellulose (HEC, 1.0%, mass percentage) was used as the only non-gel sieving medium solution, some Lambda DNA fragments could not be separated. After polyvinylpyrrolidone (PVP, 2%, mass percentage) being added into the medium solution, PVP and HEC formed a network colloidal solution in buffer, and changed the network hole size of sieving media. In addition, the results showed that PVP could restrain the adsorption of capillary to DNA, reduced electroosmotic flow, and improved the selectivity of separation. For the first time, all fragments of Lambda DNA marker was separated completely under the same condition of mixed sieving medium solution. The method was applied to separate two groups of DNA fragments of halobacterium halobium, and the base pair number was conjectured.

Cellulose↗

[Improvement of a method for separation and determination of amino acids].

A method for separation and determination of amino acids using pre-column derivatization with 6-aminoquinoline-N-hydroxysuccinimido-carbamate (AccQ. Tag) was improved. The technique developed for rapid separation and determination of amino acids by AccQ. Tag method is described. The 18 amino acids and taurine are rapidly separated and determined by AccQ. Tag special chromatographic column(3.9 mm i.d. x 150 mm) within 17.5 min(the analysis period is 22.5 min) by changing the flow rate from 1.0 mL/min to 2.0 mL/min. In place of the AccQ. Tag special chromatographic column, the Nova-Pak C18 column(3.9 mm i.d. x 150 mm), Nova-Pak C18 column(4.6 mm i.d. x 150 mm), Symmetry C18 column(3.9 mm i.d. x 150 mm) or Waters Xterra RP-18 column, can be used to separate and determine the amino acids rapidly in the same manner. But among them the Symmetry C18 column is the best substitute for AccQ. Tag column. The separation time is 14.5 min and the analysis period is 20.0 min only. The price is much cheaper than the AccQ. Tag column.

Amino Acids↗