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Comparative Study (comparative + study)
Kinds of Comparative Study Selected AbstractsP-26 CONVENTIONAL V THIN LAYER TECHNIQUES: A COMPARATIVE STUDY OF BRONCHIAL SPECIMENS USING CONVENTIONAL AND TWO LBC METHODS, THINPREP AND SUREPATHCYTOPATHOLOGY, Issue 2006J. L. Conachan The current, conventional method used is quick, easy and reasonably cheap but the nature of bronchial specimens themselves creates the need for a better preparation technique. Bronchial specimens often present with many obscuring features, such as blood and mucus, which can affect definitive diagnosis. In the study, the bronchial specimens underwent routine conventional preparation and that remaining was used to prepare an LBC slide. Both LBC methods were separately evaluated alongside the conventional method where, of the 44 specimens used, half were prepared using the conventional and ThinPrep and half with the conventional and SurePath. Evaluation forms were completed by pathologists who assessed all preparations. The results showed both LBC methods produced superior preparations that were better fixed, more cellular and had improved nuclear detail. They also removed a high percentage of background debris, were more diagnostically accurate and reduced the inadequate rate by a third. The conventional slides prepared from the same specimen as the SurePath had a lower average than those prepared with the ThinPrep. This indicated that the specimens used to evaluate the SurePath method were in fact inferior to those used for ThinPrep, with the SurePath slides showing only a slight improvement in overall quality. Despite LBC preparations reducing pathologist screening and reporting time, both methods are more labour intensive and less cost effective. The majority of laboratories are not in the financial situation to trial new methods that require extra training and more staff hours, and as such this study has highlighted an important question ,Do the benefits of better quality preparation and diagnostic accuracy offset an increase in time and cost'. [source] ECONBASE DOWNLOADS AND THE RANKING OF AUSTRALIAN UNIVERSITY ECONOMICS RESEARCH: A COMPARATIVE STUDYECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 2 2003ROBERT D. BROOKS First page of article [source] A COMPARATIVE STUDY OF THE POTENTIAL ANTIOXIDANT ACTIVITIES OF GINSENOSIDESJOURNAL OF FOOD BIOCHEMISTRY, Issue 2010SUNGWOOK CHAE ABSTRACT Ginseng roots are believed to contain over 20 different types of ginsenosides. However, no reports exist on the antioxidant activity of ginsenosides according to their various structures. The present study involves a comparison of the various forms of ginsenosides, a series of derivatives originating from the attachment of different sugar moieties to triterpene dammarane, with respect to their intracellular reactive oxygen species scavenging activity. Among the ginsenosides, Rb2 and Rc showed the strongest antioxidant activity, followed by (in decreasing order) Rg2, Rh2, Rh1, Rf, Rg3, Rg1, Rb1, Re and Rd. Furthermore, the antioxidant activity ranks of the various forms of ginsenosides were influenced by the types of dammarane, as well as the number of sugar moieties, and substitutive groups. To the best of our knowledge, this is the first report evaluating the antioxidant properties of ginsenosides with the goal of determining their structure,activity relationship. PRACTICAL APPLICATIONS Ginseng (Panax ginseng C.A. Meyer), a member of the Araliaceae family, is traditionally considered as one of the most important medicinal plants with high ginsenoside content. Ginsenoside is a triterpenoid glycoside, which is known to have diverse physiological and pharmacological activities. However, the correlation of structure and antioxidant activity has never been studied thus far in ginsenosides. A relationship exists between the type and position of the sugar moieties in ginsenoside. From these results, ginsenosides Rb2 and Rc might be very useful for the development of functional food and raw materials of medicine for antioxidants preventing oxidative stress-related diseases. And structure and antioxidant relationship may be potential for evaluating the structure and function relationship of other ginsenosides in order to elucidate which part of ginsenoside is essential with regards to increasing antioxidant activity and the development of novel antioxidants to treat diseases associated with free radicals. [source] COMPARATIVE STUDY OF MICROENCAPSULATION OF CASEIN HYDROLYSATES IN LIPOSPHERES AND LIPOSOMESJOURNAL OF FOOD BIOCHEMISTRY, Issue 1 2004HARRIMAN ALEY MORAIS The encapsulation in lipospheres and in liposomes was used with the aim of masking the bitterness of casein hydrolysates for dietetic of pharmaceutical purposes. Papain was used for preparing three casein hydrolysates, employing different temperatures and E:S ratios. The percentage of encapsulation of these preparations was measured by second derivative spectrophotometry (SDS). Lipid oxidation over a period of 60 days, was followed by quantifying the 2-thiobarbituric acid reactive substances (TBARS). Other analysis were performed for characterizing these vesicles, including the sensory evaluation and the measure of hydrophobicity. The results showed that these two encapsulation systems were equally efficient in reducing the hydrophobicity and the bitterness of casein hydrolysates. SDS was a useful tool in the characterization of these preparations. It is a quick and relatively low-cost method, and indicated that the encapsulation rate in lipospheres (65%) was higher than in liposomes (59%). The TBARS method revealed the chemical stability of these preparations over the period of study (60 days). [source] KINETIC BEHAVIOR OF SOYBEAN LIPOXYGENASE: A COMPARATIVE STUDY OF THE FREE ENZYME AND THE ENZYME IMMOBILIZED IN AN ALGINATE SILICA SOL-GEL MATRIX,JOURNAL OF FOOD BIOCHEMISTRY, Issue 1 2000AN-FEI HSU Lipoxygenase (LOX) is an enzyme that regioselectively introduces a hydroperoxide into polyunsaturated fatty acids (PUFA). We recently reported a procedure that immobilizes soybean LOX within an alginate sol-gel matrix. In this study, the kinetic profile of free LOX was compared with that of the sol-gel immobilized LOX. The temperature dependent activity profile of free LOX was optimal at 25C whereas immobilized LOX had optimal activity over the temperature range of 25,35C. Enzyme activity, measured in aqueous buffer, for both the free and immobilized LOX preparations had Km values of 2.5 and 1.40 mmoles/L, respectively, and Vmax values of 0.056 and 0.02 ,mol/min, respectively. The relative rates of oxidation of linoleic acid and acylgfycerols containing linoleoyl residues catalyzed by free and immobilized LOX also were determined The results showed that both free and immobilized LOX favor linoleic acid as a substrate. Relative substrate preference for free LOX was linoleic acid >1-monolinolein > 1,3-dilinolein >trilinolein, and for immobilized LOX was linoleic acid >l, 3-dilinolein >1-monolinolein >trilinolein. In general, LOX immobilized in alginate silica sol-gel matrix retained the physical and chemical characteristics of free LOX. [source] COMPARATIVE STUDY OF EGG WHITE PROTEIN AND EGG ALTERNATIVES USED IN AN ANGEL FOOD CAKE SYSTEMJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2010MAHMOUD ABU-GHOUSH ABSTRACT Comparisons of the physical and sensory properties of several commercial egg alternatives in angel food cake formulation were studied. Fourteen samples were investigated for foaming properties at 10 and 20 min whipping time: collagen, Cryogel gelatin, Solugel collagen hydroysates, gelatin, whey protein concentrate, fish protein, whey protein isolate (95% WPI, 90%WPI), hydrolyzed whey protein isolate, pea protein, rice protein concentrate, soy protein, corn zein and casein. However, only eight samples showed potential and were moved forward for further evaluation. Only the WPI alternative was able to maintain a meringue during baking. All other foams collapsed during the baking process. The angel food cake formulated with WPI exhibited a significantly firmer crust and crumb compared with the egg white control. The L value, height and volume of control cake were also significantly higher than the egg alternative. The control significantly outperformed the angel food cake formulated with the egg alternative in all sensory categories evaluated. PRACTICAL APPLICATIONS The egg alternatives were used to replace egg as a functional ingredient in angel cake productions. These alternatives can deliver functionality at a lower cost and can be incorporated to produce a suitable angle cake, especially whey protein isolate (WPI). These results may help producers in formulating angle cake that rely on WPI as an egg alternative. [source] COMPARATIVE STUDY OF SHELL SWAB AND SHELL CRUSH METHODS FOR THE RECOVERY OF SALMONELLA FROM SHELL EGGSJOURNAL OF FOOD SAFETY, Issue 4 2008T. KAWASAKI ABSTRACT Swabbing is the standard methodology for the recovery of resident microorganism from shell eggs in Japan. A comparative study of shell swab (SW) and shell crush (CR) techniques was performed to recover the laboratory-inoculated Salmonella from shell eggs. It was found that the recovery of Salmonella by CR methods was significantly higher (4.5,7.5 log cfu/egg) than that of SW methods (3.1,6.3 log cfu/egg). However, analyses with quantitative real-time polymerase chain reaction (invA as a target gene), fluorescent microscopic and quantitative analyses with a Live/Dead BacLight bacterial viability kit revealed that not all of the inoculated Salmonella spp. populations were recovered as intact cells by either method. The chemiluminescent bacterial viability assay showed that chemiluminescence intensity (CI) began to increase after 30 min in CR samples; on the other hand, SW samples did not show any increase in CI for 2 h. These results suggest that SW might cause more damage and lethality to cells than CR. In addition, to determine the most appropriate method for recovering resident aerobic bacteria, coliforms and Salmonella spp from shell eggs, 4,000 commercial eggs were collected and sampled by shell rinse (SR) and CR techniques using phosphate-buffered saline (PBS) warmed to different temperatures. PBS at 37C was found to be the best recovery solution and temperature, respectively, for recovering aerobic microorganisms from shell eggs by both methods and the CR methods recovered a higher population than did the SR methods (4.9 versus 5.8 log cfu/egg for SR and CR methods, respectively; n = 500 eggs/method). Therefore, the CR method along with recovery buffer (PBS) at 37C could be an effective technique for the recovery of microorganisms from post-processed shell eggs. PRACTICAL APPLICATIONS There is a need to develop a rapid and highly sensitive method for the recovery of microorganisms from shell eggs. Such recovery methods are also useful for evaluating the efficacy of newly developed shell egg disinfection techniques. Many methods involving rinsing, swabbing, and crushing of shell eggs have been reported; however, we performed a comparative study of the method used to recover the Salmonella from shell eggs. We found that the shell crush method (CR) was superior to the shell swab method (SW) for the recovery of Salmonella spp., and phosphate-buffered saline (PBS) at 37C was found to be the best recovery solution and temperature, respectively, for recovering microorganisms from shell eggs by both methods. Therefore, the CR method along with recovery buffer (PBS) at 37C could be an effective technique for the recovery of microorganisms from post-processed shells. Use of this method could be recommended for the microbial evaluation of post-processed shell eggs in industries. [source] AN SEM-BASED ANALYSIS OF THE MORPHOLOGY, ANATOMY, AND REPRODUCTION OF LITHOTHAMNION TOPHIFORME (ESPER) UNGER (CORALLINALES, RHODOPHYTA), WITH A COMPARATIVE STUDY OF ASSOCIATED NORTH ATLANTIC ARCTIC/SUBARCTIC MELOBESIOIDEAE,JOURNAL OF PHYCOLOGY, Issue 5 2005Walter H. Adey Lithothamnion tophiforme (Esper) Unger is a dominant, arctic, saxicolous species that extends southward, albeit with reduced cover, into the deeper colder waters of the North Atlantic subarctic, where it also occurs in significant rhodolith deposits with L. glaciale. The external appearance of L. tophiforme is distinctive, but typification, anatomy, reproduction, ecology, and biogeography have not been previously analyzed. These topics are now addressed, with extensive use of SEM, in comparison with other North Atlantic arctic and subarctic melobesioid genera and species. The species considered in this article comprise 95% of the coralline biomass of the colder North Atlantic and adjacent arctic (i.e. less than 12° C summer and less than 0° C winter). In the outer thallus region of coralline algae, crust extension proceeds, calcification develops, surface sloughing and grazing occur, and reproductive structures are initiated. Analysis of the ultrastructure of the outer thallus region (epithallium, meristem, and perithallium) of L. tophiforme shows distinctive generic similarities and specific differences from the other Lithothamnion species discussed here. Considerable generic differences from the Clathromorpum and Leptophytum species also encountered in the region considered are highlighted as well. We discuss the functional and taxonomic implications of these distinguishing features and recommend that they be more widely considered in future research on coralline algae to understand more fully the ecology and evolution of the Corallinales. [source] EVALUATION OF OLFACTORY INTENSITY: COMPARATIVE STUDY OF TWO METHODSJOURNAL OF SENSORY STUDIES, Issue 4 2004BORIANA ATANASOVA ABSTRACT Two experimental procedures recommended for the evaluation of the psychophysical characteristics of odorous compounds, olfactory matching with the 1-butanol scale and cross-modality matching with the finger span are compared. The intensity of ethyl butyrate and guaiacol solutions presented at four different concentration levels was evaluated by a panel of sixteen subjects over five repetitions using the two methods. Each stimulus was delivered to the subject from a Teflon bag through a nose-shaped glass sniffing port. The discrimination ability, repeatability, panel homogeneity and within-subject variability of the methods were assessed. Results indicate that with both methods, subjects were able to highly discriminate the presented concentration levels of the odorants. There were no great difference in repeatability and the same individual variability was observed between both methods. However, the smaller within-subject variability highlighted for the 1-butanol scale method suggested that this method is potentially more powerful than finger-span method. [source] A COMPARATIVE STUDY OF THE PERFORMANCE OF SELECTED IN-LINE VISCOMETERS ON NEWTONIAN AND SHEAR-THINNING FLUIDS,JOURNAL OF TEXTURE STUDIES, Issue 2 2001LAURA A. ZIMMER Three commercial instruments for in-line process measurement of fluid viscosity (an oscillating sphere viscometer, a tube viscometer and a coaxial cylinder viscometer) were evaluated using a Newtonian (60% sucrose) and two shear-thinning fluids (0.5% xanthan gum and 2% hydroxypropyl methylcellu-lose). The oscillating sphere viscometer required little or no calibration to measure the viscosity of Newtonian fluids. Otherwise, when compared to results given by analytical off-line rheometry, the in-line viscometers were found to be grossly inaccurate in predicting viscosity. A methodology is presented to correct the flow curves generated by each in-line instrument such that the output measurements are consistent with that given by off-line rheometry. Additional characteristics of each instrument that should be considered when choosing an instrument for in-line process application are presented. [source] PATIENT AGE IS A STRONG INDEPENDENT PREDICTOR OF 13C-AMINOPYRINE BREATH TEST RESULTS: A COMPARATIVE STUDY WITH HISTOLOGY, DUPLEX-DOPPLER AND A LABORATORY INDEX IN PATIENTS WITH CHRONIC HEPATITIS C VIRUS INFECTIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 4 2006Arne RJ Schneider SUMMARY 1Noninvasive tests for the staging of chronic hepatitis C virus (HCV) infection would be an attractive alternative to liver biopsy. The 13C-aminopyrine breath test (ABT) has been proposed for the noninvasive assessment of hepatic function and partly correlates with fibrosis. We aimed to investigate causes for the lack of discriminatory power for different degrees of hepatic fibrosis. 2Eighty-three patients (median age 49 years (28,78 years)) with chronic HCV infection underwent the ABT after an oral load of 75 mg N,N-dimethyl- 13C-aminopyrine. Portal vein flow was assessed by duplex-Doppler and a laboratory index (aspartate aminotransferase to platelet ratio index or APRI) was calculated. Parameters were compared with liver histology. 3The cumulative 13C-recovery differed significantly between patients without relevant fibrosis (fibrosis score 0,2) and cirrhosis (5,6), beginning after 30 min of sampling (P < 0.05). The ABT did not discriminate patients with fibrosis scores 3,4 from the remaining two patient groups. Sensitivity and specificity for the prediction of cirrhosis was 73.4,82.8% and 63.2,68.4%, depending on the sampling time. Compared with the fibrosis score (P = 0.04), patient age was a highly significant independent predictor for the 13C-recovery (P < 0.0001). Aspartate aminotransferase to platelet ratio index and duplex-Doppler predicted cirrhosis with 76.6%vs. 87.5% sensitivity and 63.2%vs. 68.4% specificity. 4Our data suggest an age-dependent decrease of cytochrome P450 activity which probably accounts for the large overlap of ABT results that preclude clear differentiation. This is also consistent with former pharmacodynamic trials. Age-adapted reference ranges could improve ABT results. [source] A Comparative Study of Modal Parameter Identification Based on Wavelet and Hilbert,Huang TransformsCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2006Banfu Yan Special attention is given to some implementation issues, such as the modal separation and end effect in the WT, the optimal parameter selection of the wavelet function, the new stopping criterion for the empirical mode decomposition (EMD) and the end effect in the HHT. The capabilities of these two techniques are compared and assessed by using three examples, namely a numerical simulation for a damped system with two very close modes, an impact test on an experimental model with three well-separated modes, and an ambient vibration test on the Z24-bridge benchmark problem. The results demonstrate that for the system with well-separated modes both methods are applicable when the time,frequency resolutions are sufficiently taken into account, whereas for the system with very close modes, the WT method seems to be more theoretical and effective than HHT from the viewpoint of parameter design. [source] Comparative Study of Flat and Round Collectors Using a Validated 1D Fluid Probe ModelCONTRIBUTIONS TO PLASMA PHYSICS, Issue 5-6 2006P. Peleman Abstract In the literature two different types of Gundestrup-like probe designs are proposed: design with flat and with round collectors. In this paper we study the influence of different collector shapes of Gundestrup-like probes on the accuracy of the measurement of the parallel and perpendicular flows. A one dimensional fluid probe model is used for deducing both Mach numbers of the unperturbed flow from the probe data. An analytical expression relates the plasma flow to the measured ion saturation currents collected at the upstream and downstream collecting surfaces of the probe. For flat collectors, the analytical model is validated by comparing it to a two dimensional quasi-neutral Particle In Cell (PIC) simulation code. An extension of the theoretical model then allows us to study round collectors. We performed an accuracy study which showed that systematic errors are introduced when round collectors are employed for determination of the perpendicular flow which is systematically overestimated. The error can reach more than 70% when the perpendicular flow increases and when the angle of the collecting surface with respect to the magnetic field (, , 0)is small. The correct analytical expression is applied to experimental data from Gundestrup probe measurements with round collectors on the CASTOR tokamak. The analysis shows that for these measurements the error introduced by using the expression for flat collectors remains negligible, supporting our former use of the model for flat collectors. A new advanced Gundestrup-like probe design and the motivation for the choice of flat collectors are presented. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The Implementation of Innovation by a Multinational Operating in Two Different Environments: A Comparative StudyCREATIVITY AND INNOVATION MANAGEMENT, Issue 2 2002Mohamed Zain The aim of the paper is to examine the innovation initiatives and processes followed by two subsidiaries of a German multinational company operating in Europe and Asia and to compare the innovativeness of their operations in these two locations. The study examined the innovation processes followed by the two subsidiary firms operating in Germany and Malaysia, the actual problems faced by them, the critical success factors involved in the implementation, and the work climates of the firms. Interestingly, it was found that both firms followed similar innovation processes. Nevertheless, different types of problems and critical success factors were applicable to both firms. The results showed that the Malaysian subsidiary faced more behavioural problems while the German subsidiary encountered more technical problems. Further, the study showed that a lack of knowledge was the common problem faced equally by both firms. The study demonstrated that the German subsidiary had better working climate compared to its counterpart in Malaysia. Finally, the German subsidiary was found to be more innovation,active than the Malaysian subsidiary as it introduced more types of innovation, interacted with more types of entity in the external environment and introduced more types of training. [source] Cold Air Anesthesia in Dermasurgery: Comparative StudyDERMATOLOGIC SURGERY, Issue 1 2006PHILIP S. H. HUGHES MD No abstract is available for this article. [source] Treatment of Pigmented Hypertrophic Scars with the 585 nm Pulsed Dye Laser and the 532 nm Frequency-Doubled Nd:YAG Laser in the Q-Switched and Variable Pulse Modes: A Comparative StudyDERMATOLOGIC SURGERY, Issue 8 2002Leyda Elizabeth Bowes MD background. Pigmented hypertrophic scars are a difficult condition to treat. They may result from traumatic injuries or from surgical and cosmetic procedures. The 585 nm flashlamp-pumped pulsed dye laser (FLPDL) has been used to treat this condition, with significant improvement of varying degrees. It remains to be determined whether other laser modalities may have a similar or even greater success in the treatment of pigmented hypertrophic scars. objective. To determine the efficacy of the 532 nm frequency-doubled Nd:YAG laser in the treatment of pigmented hypertrophic scars as compared to the 585 nm FLPDL. methods. Six patients with pigmented hypertrophic scars and skin phototypes II,IV were chosen. A scar was selected for treatment in each patient and divided into four equal 2 cm segments. Three segments were each treated with a different laser modality and one was left untreated to serve as the control. A 585 nm FLPDL was used with an energy of 3.5 J, a pulse duration of 450 ,sec, and a 10 mm spot size. A 532 nm Q-switched frequency-doubled Nd:YAG laser was set to an energy of 2.8 J, a 10-nsec pulse, and a 3 mm spot size. The same 532 nm laser was set to the variable pulse mode to treat a 2 cm scar segment, with an energy of 9.5 J, a 10-msec pulse, and a 4 mm spot size. An average of 3.3 treatments were performed on each scar segment, at intervals of 4,6 weeks and long-term follow-up at 22 weeks. Treatment outcome was graded by a blind observer using the Vancouver General Hospital (VGH) Burn Scar Assessment Scale. A SigmaStat t -test was used to determine the statistical significance of the values obtained. results. Treatment of pigmented hypertrophic scars with the 532 nm Q-switched Nd:YAG laser led to a significant improvement of 38% in the VGH scores when compared to baseline (P = .005). The 585 nm FLPDL also had a favorable effect on the scars, with an average improvement of 36.1% in the VGH scores. There was no significant difference noted between the outcome of treatment with either of these two lasers. Treatment with the 532 nm variable pulse Nd:YAG laser led to a 19% improvement in the VGH scores of scars, which did not differ significantly from the 16.1% improvement observed in control scars on the last follow-up visit. No side effects or complications from treatment were noted or reported during the course of the study. At the conclusion of the study, five of six patients chose the segment treated with the 532 nm Q-switched Nd:YAG laser as the best segment overall. conclusion. The 532 nm Q-switched Nd:YAG laser and the 585 nm FLPDL offer comparable favorable results in the treatment of pigmented hypertrophic scars. The 532 nm Q-switched Nd:YAG laser may be preferred by patients particularly distressed by the dark color of their scars. [source] China's Rangelands under Stress: A Comparative Study of Pasture Commons in the Ningxia Hui Autonomous RegionDEVELOPMENT AND CHANGE, Issue 2 2000Peter Ho China's economic reforms have exacerbated the problems of over-grazing and desertification in the country's pastoral areas. In order to deal with rangeland degradation, the Chinese government has resorted to nationalization, or semi-privatization. Since the implementation of rangeland policy has proved very difficult, however, experiments with alternative rangeland tenure systems merit our attention. In Ningxia, in northwest China, local attempts have been undertaken to establish communal range management systems with the village as the basic unit of use and control. Some of these management regimes are under severe stress, due to large-scale digging for medicinal herbs in the grasslands. This digging has resulted in serious conflicts between Han and Hui Muslim Chinese, during which several farmers have been killed. It is against this backdrop that this article explores the institutional dynamics of range management in two different villages. [source] Innovation and Peripherality: An Empirical Comparative Study of SMEs in Six European Union Member CountriesECONOMIC GEOGRAPHY, Issue 1 2008Andrew Copus Abstract This article examines the rates of innovative activity of small and medium-sized enterprises (SMEs) in central areas and equally developed but less accessible areas in six European Union member states. The probability of innovating is well predicted by the observable characteristics of firms, entrepreneurial characteristics, and business networks. More accessible areas consistently present higher rates of innovative activity than do their peripheral counterparts. The difference in the rates of peripheral and central areas is decomposed into observable and non-observable factors. The entire innovation gap is attributed to nonobservable factors that constitute a combination of behavior and environment. Innovation policy for SMEs should aim to meet businesses' specific needs (firm-specific factors) and to sustain and improve the innovative environment. [source] Comparative Study of Cyanobacteria as Biocatalysts for the Asymmetric Synthesis of Chiral Building BlocksENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 2 2006J. Havel Abstract The three representative cyanobacteria, Synechococcus PCC7942, Anabaena variabilis, and Nostoc muscorum, were studied for their ability to asymmetrically reduce the prochiral ketones 2,-3,-4,-5,-6,-pentafluoroacetophenone, ethyl 4-chloroacetate, 4-chloroacetophenone, and ethylbenzoylacetate to the corresponding chiral alcohols. Photosynthesis as well as respiration was applied for intracellular regeneration of the NAD(P)H cofactor. It was shown for the first time that all cyanobacteria were able to reduce the prochiral ketones asymmetrically without light for cofactor regeneration. By comparison of the cell specific product formation capacities of cyanobacteria with typical heterotrophic whole cell biocatalysts in batch processes, it is shown that comparable or, in some cases, better performances at high enantiomeric excess (ee > 99.8,%) are obtained. As a consequence of a generally strong product inhibition, in situ product removal must be applied in order to restore process efficiency when using cyanobacteria as biocatalysts. [source] Computerized Tremor Analysis of Valproate-induced Tremor: A Comparative Study of Controlled-release versus Conventional ValproateEPILEPSIA, Issue 2 2005Martina Rinnerthaler Summary:,Purpose: Valproate (VPA) induces postural tremor in 6,45% of patients. The characteristics of VPA-induced tremor have not yet been quantitatively assessed, and it is not known whether tremor prevalence or severity is affected by VPA formulation (controlled-release CR-VPA vs. conventional VPA). The aim of this study was quantitatively to assess tremor in epilepsy patients receiving VPA and to compare the effects of two VPA formulations (CR-VPA vs. VPA) on tremor severity. Methods: In a prospective study, 18 consecutive patients with newly diagnosed focal or generalized epilepsy were assigned to receive alternately either VPA (n = 10) or CR-VPA (n = 8) monotherapy. Computerized tremor analysis was performed at baseline 1 day before initiating VPA treatment and repeated after a seizure-free period of ,8 weeks, during which VPA doses had remained stable. Rest and postural tremor were recorded by accelerometry, and surface electromyograms (EMGs) were recorded from the wrist flexors and extensors. Results: At baseline, the two groups had similar postural tremor amplitudes. At follow-up, the CR-VPA group had remained at the same level, whereas VPA subjects exhibited a significant increase in tremor amplitudes (p < 0.05) despite comparable VPA doses and comparable plasma VPA concentrations at the time of tremor testing. Conclusions: This is the first study to assess quantitatively VPA-induced tremor by standardized tremor analysis. These results suggest that CR-VPA may cause less tremorigenic activity as compared with standard VPA. The mechanisms underlying this difference are unclear but may include greater peak,trough variation with VPA than with CR-VPA. [source] Childhood Epilepsy Due to Neurocysticercosis: A Comparative StudyEPILEPSIA, Issue 11 2001Lisiane S. Ferreira Summary: ,Purpose: To assess the clinical profile of pediatric patients with epilepsy and neurocysticercosis (NC), and compare them with a group of pediatric patients with benign partial epilepsy to determine clinical differences, response to treatment, and prognosis. Methods: We studied 28 patients (16 girls) with probable or definitive diagnosis of NC and epilepsy and 32 patients (16 girls) with partial benign epilepsy (BE). All patients had normal neurologic examination. We compared NC and BE patients looking for differences in demographics (age at first seizure, gender, family history); clinical presentation (type, frequency, duration, and total number of seizures, duration of epilepsy, status epilepticus, cluster, and postictal deficit); treatment [duration, number of antiepileptic drugs (AEDs), maximal dose, drug association, number of seizure-free patients, time to obtain control and recurrence after medication discontinuation]; complementary examinations (the first and the last EEG). Results: The mean follow-up was 5.4 years for the 28 NC patients and 4.6 years for the 32 BE patients (p = 0.98). We did not find statistical differences between NC and BE in gender, family history, types of seizures, frequency and length of seizures, previous status epilepticus, seizure clustering, and presence of postictal deficits. However, we found that NC compared with BE patients had significant longer AED treatment, more seizures after AED introduction, tried more AEDs and at maximal dose, and in 20%, required polytherapy. The recurrence rate in NC was 54.4% and this was not significantly associated with number of lesions and disease activity seen on CT scans or the presence of EEG abnormalities. Conclusions: NC presents with a mild form of epilepsy in terms of seizure severity; however, it is more challenging in regard to drug management and has a less favorable long-term prognosis in terms of seizure remission. The number of lesions or disease activity seen on computed tomography (CT) as well as EEG abnormalities have no prognostic value in childhood epilepsy due to NC. [source] The Impact of Institutional Differences on Derivatives Usage: a Comparative Study of US and Dutch FirmsEUROPEAN FINANCIAL MANAGEMENT, Issue 3 2003Gordon M. Bodnar F30; G15; G32 Abstract This paper examines the influence of institutional differences on corporate risk management practices in the USA and the Netherlands. We compare results to surveys in each country using a strategy that corrects for differences over industry and size classes across the Dutch and US samples. We document several differences in the firms' uses and attitudes towards derivatives and attempt to attribute them to the differences in the institutional environments between the USA and the Netherlands. We find that institutional differences appear to have an important impact on risk management practices and derivatives use across US and Dutch firms. [source] A Comparative Study of the Optical and Electroluminescent Properties of EuIII Complexes with TTA and 2-(2,-Pyridyl)azoles: The Crystal Structure of [Eu(TTA)3(PBO)]EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 18 2006Li-Hua Gao Abstract Two EuIII mixed-ligand complexes, namely [Eu(TTA)3(PBO)]and [Eu(TTA)3(PBT)] [TTA = 1,1,1-trifluoro-3-(2-thenoyl)acetonato, PBO = 2-(2,-pyridyl)-1,3-benzoxazole, and PBT = 2-(2,-pyridyl)-1,3-benzothiazole], have been synthesized. [Eu(TTA)3(PBO)] has been structurally characterized by single-crystal X-ray diffraction analysis. The complex crystallizes in the monoclinic space group C2/c. The lattice parameters are a = 41.346(4), b = 10.0538(8), c = 20.3793(16) Ĺ, , = 110.922(2)°, Z = 8. The EuIII ion is eight-coordinate, with three bidentate TTA, anions and one bidentate N,O-chelated PBO molecule. A comparative study by UV and emission spectroscopy was carried out and electroluminescent properties of the related complexes [Eu(TTA)3(PBO)] and [Eu(TTA)3(PBT)] are reported as well. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Introduction of Aromatic and Heteroaromatic Groups in the 2- and 8-Positions of the Tröger's Base Core by Suzuki, Stille and Negishi Cross-Coupling Reactions , A Comparative StudyEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 16 2005Carlos Solano Abstract A comparative study on the bis(functionalization) of the Tröger's base core by aromatic and heteroaromatic groups using palladium-catalyzed cross-coupling reactions is presented. Three different reactions, the Suzuki, Stille, and Negishi couplings, were investigated using Tröger's base analogues equally substituted in the 2,8-positions with (HO)2B, Bu3Sn and ZnCl groups, respectively, as the metallated component. Six aryl halides with different electronic and steric properties were employed as coupling partners. The presence of the bulky and electron-rich phosphane P(tBu)3 as co-catalyst was found to play an important role. In addition, the palladium source, [Pd(PPh3)4] or [Pd2(dba)3], was also found to be an important factor for the yield of the reactions. The Suzuki coupling was found to be the best method in general, giving excellent yields for most aryl halides, whereas the Stille and Negishi couplings gave moderate to good yields. Finally, the crystal structures of the 4-nitrophenyl- and the 2-pyridyl-appended analogues of Tröger's base, 7d and 7f, are presented in the Supporting Information. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005) [source] Ideas and Environmental Standard-Setting: A Comparative Study of Regulation of the Pulp and Paper IndustryGOVERNANCE, Issue 1 2002Kathryn Harrison This article examines the policy responses of Canada, Sweden, and the United States to the discovery of dioxins in pulp mill effluents and paper products, with particular attention to the impact of science and the scientific community on national environmental standards. Important areas of policy divergence were found, despite considerable scientific consensus among environmental scientists in the three jurisdictions, as the potential force of shared causal knowledge was undermined by competing domestic interests and different institutional contexts for decision-making. This analysis challenges the emphasis of the epistemic community literature on the role of scientists in promoting policy convergence, underscoring the importance of the interaction of ideas, interest group politics, and institutions in public policy-making. [source] A Retrospective, Comparative Study on the Frequency of Abuse in Migraine and Chronic Daily HeadacheHEADACHE, Issue 3 2007B. Lee Peterlin DO Objective.,To assess and contrast the relative frequency of a past history of physical and/or sexual abuse in patients with chronic daily headache (CDH) versus migraine. Background.,A number of risk factors have been identified as risk factors for chronification of headache disorders. Limited data exist regarding the influence of physical and/or sexual abuse on primary headache disorders. Methods.,This was a retrospective chart review of 183 consecutive new headache patients seen from December 2004 through August 2005 at an outpatient tertiary-care center. Patients were included in the study if they had chronic daily headache (with criteria for medication over-use headache or chronic migraine), or migraine with or without aura. A history of physical and/or sexual abuse was systematically asked of all headache patients at their first visit in the clinic. This information was then transferred to a semi-standardized form and the relative frequency of abuse in both groups contrasted. Results.,Of the 161 patients included in the study, 90.1% were female with a mean age of 36.4 ± 12.0. A total of 59.0% of the patients were diagnosed with CDH and 41.0% were diagnosed with migraine. Overall, 34.8% of all patients, 40.0% of CDH patients, and 27.3% of migraine patients had a history of physical and/or sexual abuse. The relative frequency of a history of physical and/or sexual abuse was higher in the CDH group as compared to the migraine group (P= .048). Conclusion.,The relative frequency of abuse is higher in CDH sufferers than migraineurs, suggesting that physical and sexual abuse may be risk factors for chronification. [source] Liberating Anger, Embodying Knowledge: A Comparative Study of María Lugones and Zen Master HakuinHYPATIA, Issue 2 2010JEN MCWEENYArticle first published online: 9 DEC 200 This paper strengthens the theoretical ground of feminist analyses of anger by explaining how the angers of the oppressed are ways of knowing. Relying on insights created through the juxtaposition of Latina feminism and Zen Buddhism, I argue that these angers are special kinds of embodied perceptions that surface when there is a profound lack of fit between a particular bodily orientation and its framing world of sense. As openings to alternative sensibilities, these angers are transformative, liberatory, and deeply epistemological. [source] A Comparative Study of Arm-Restraint Methodology: Differential Effects of Mother and Stranger Restrainers on Infants' Distress Reactivity at 6 and 9 Months of AgeINFANCY, Issue 3 2009Christin L. Porter This study examined both differential patterns and the stability of infants' (N = 70) distress reactivity across mother and stranger arm-restraint conditions when infants were 6 and 9 months of age. Reactivity measures included observational variables for the rise, intensity, and duration of infant distress as well as motor activities associated with escape behaviors. Correlation analyses revealed that infant behaviors during arm restraint were modestly stable across conditions and over time; however, mean comparisons also showed that infants' distress responses appear to be sensitive to protocol parameters (whether restrainer is mother or stranger). At 6 months of age, infants cried more during maternal restraint than with strangers and exhibited escape behaviors more frequently with mothers. Findings further indicate that infants' distress reactivity undergoes developmental alterations from 6 to 9 months of age, with infants crying more quickly, reaching peak intensity of distress faster, and displaying more distress at 9 months compared to 6 months. These changes in infants' reactivity were particularly accentuated during maternal compared to stranger restraint conditions at 9 months of age. [source] A Comparative Study of Galvanic Replacement Reactions Involving Ag Nanocubes and AuCl2, or AuCl4,,ADVANCED MATERIALS, Issue 13 2008Leslie Au Galvanic replacement of Ag nanocubes with AuCl2, and AuCl4, results in morphological, compositional, and spectral differences that provide insight into the reaction mechanism by which hollow/porous gold nanostructures can be prepared for biomedical applications. [source] Ethnic Stratification and Inter-Generational Differences in Japan: A Comparative Study of Korean and Japanese Status AttainmentINTERNATIONAL JOURNAL OF JAPANESE SOCIOLOGY, Issue 1 2003Myungsoo Kim Abstract: There are plenty of stereotypical discourses concerning the Korean minority in Japan that are widely accepted, not because of their plausibility, but because of the lack of basic empirical data. In order to fill this intellectual vacuum, I conducted a social stratification and mobility survey focusing on resident Korean men in 1995, comparable with the Japanese sample. The purpose of this article is exploratory rather than aimed at hypothesis testing, given the extreme paucity of the earlier empirical data for the ana-lysis of Korean minority status attainment. The results show that: 1For the Korean minority in Japan, class resources translate into educational attainment to a much lower extent than for the Japanese. 2Korean status attainment patterns deviate from those of their Japanese counterparts. For the Japanese, the crucial status attainment path is secured through educational attainment, which is not the case among Koreans. 3Despite being denied access to such mainstream status attainment paths, major status indicators for Koreans are not significantly different than those of Japanese, and regarding this equality of outcomes, one of the possible explanations is that Korean ethnic disadvantages in the status attainment process may have been overcome by mobilizing informal bilateral ethnic networks. [source] | ||||||||||||||||||||||||||||||||||||||||