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Traditional Techniques (traditional + techniques)
Selected AbstractsGenetic Algorithms for Optimal Urban Transit Network DesignCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 3 2003Partha Chakroborty This article attempts to highlight the effectiveness of genetic algorithm (GA),based procedures in solving the urban transit network design problem (UTNDP). The article analyzes why traditional methods have problems in solving the UTNDP. The article also suggests procedures to alleviate these problems using GA,based optimization technique. The thrust of the article is three,fold: (1) to show the effectiveness of GAs in solving the UTNDP, (2) to identify features of the UTNDP that make it a difficult problem for traditional techniques, and (3) to suggest directions, through the presentation of GA,based methodologies for the UTNDP, for the development of GA,based procedures for solving other optimization problems having features similar to the UTNDP. [source] Symbolic dynamics for identifying similarity between rhythms of ecological time seriesECOLOGY LETTERS, Issue 9 2004Bernard Cazelles Abstract Explaining the associations between animal populations or between population and environmental signals is an important challenge. The time series that quantify animal populations are often complex, nonlinear, noisy and non-stationary. These characteristics may make it inappropriate to use traditional techniques when analysing these time series and their mutual dependencies. Here I propose to use symbolic dynamics and techniques from Information Theory to evaluate the degree of dynamic cohesion between time series fluctuations. The main idea is to check whether two (or more) signals tend to oscillate simultaneously, rising and falling together with the same rhythm. Based on synthetic and real time series, I demonstrate that this method is robust to the presence of noise and to the short length of the analysed time series and gives relevant information about the weak relationships between different series. Furthermore, this method appears as simple as classical cross-correlation and outperforms it in the analysed examples. [source] A fuzzy analytic hierarchy process approach in modular product designEXPERT SYSTEMS, Issue 1 2001W.B Lee Product development stages. The analytic hierarchy process (AHP), which breaks down a complex problem into simple hierarchical decision-making processes, can be incorporated with fuzzy logic to suggest the relative strength of the factors in the corresponding criteria, thereby enabling the construction of a fuzzy judgement matrix to facilitate decision-making. This paper proposes a fuzzy AHP approach in modular product design complemented with a case example to validate its feasibility in a real company. Test findings indicate that the approach is helpful for providing key decision support information in terms of product module selection during product development stages. The significance of the contribution of this paper is the suggestion of a novel approach in modular product design, embracing a combination of computational intelligence and traditional techniques, thereby providing more alternatives and ideas for those researchers who are interested in this field of study. [source] Towards a multidisciplinary approach to structuring in reduced saturated fat-based systems , a reviewINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2010Paul Wassell Summary Although many food products are essentially emulsions, interest in the structuring of oil-continuous emulsions (and in specific cases water-continuous emulsions) is intense, particularly to meet the continuing challenge of reducing the degree of saturates in food systems. Consequently, it is necessary to observe the effects of structurants and to examine their impacts on current food systems. This is especially the case where novel structuring materials are used to wholly or partially replace traditional structurants. A multidisciplinary approach is discussed encompassing traditional and novel mechanisms considered able to structure within low saturated fat-based systems and which in themselves could also have emulsification properties. The presence of interfacial compositions as in emulsions requires a crucial understanding of the interactions within these compositions for the creation of building blocks in oil or fat structuring. Where a co-surfactant structure may be used, together with novel structurants, for example, wax esters, phytosterols, it is necessary to understand how these may influence interfacial film thickness, strength and flexibility. Understanding how to measure mechanical visco-elastic properties of structurant interactions both in model and real time dynamic measurements will be necessary to account for diffusion, orientation and self-assembly mechanisms. This review discusses combining traditional techniques with novel structurant technology; developing and validating dynamic measurement techniques; and investigation of real systems as opposed to purely model systems. [source] Comparison of some properties on the different types of pestil: a traditional product in TurkeyINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2005Ozlem Cagindi Summary Pestil is a traditional dried fruit snack, which is consumed in Turkey. Wheat starch is mixed with different clarified fruit juices such as grape, mulberry, apricot or plum and cooked using traditional techniques. In this work the proximate chemical composition (moisture, ash, fat, crude protein and total carbohydrate), energy value and thickness of grape, apricot and mulberry pestils were investigated. The colour properties (Hunter L, a and b) were determined by a Minolta Chroma-Meter and the mineral content (Ca, Fe, K, Mg, Na, Cu, Zn, Mn) of each product was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The carbohydrate value of pestil samples ranged between 73.7 and 82.4% and energy value was between 321.5 and 356.4 kcal 100 g,1. Mulberry pestil was a better source of energy than grape and apricot pestils. Apricot pestils were rich in calcium, sodium and zinc, and mulberry pestil samples were rich in magnesium. [source] Adaptive modeling and discovery in bioinformatics: The evolving connectionist approachINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 5 2008Nikola Kasabov Most biological processes that are currently being researched in bioinformatics are complex, dynamic processes that are difficult to model and understand. The paper presents evolving connectionist systems (ECOS) as a general approach to adaptive modeling and knowledge discovery in bioinformatics. This approach extends the traditional machine learning approaches with various adaptive learning and rule extraction procedures. ECOS belong to the class of incremental local learning and knowledge-based neural networks. They are applied here to challenging problems in Bioinformatics, such as: microarray gene expression profiling, gene regulatory network (GRN) modeling, computational neurogenetic modeling. The ECOS models have several advantages when compared to the traditional techniques: fast learning, incremental adaptation to new data, facilitating knowledge discovery through fuzzy rules. © 2008 Wiley Periodicals, Inc. [source] Clustering with artificial neural networks and traditional techniquesINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 4 2003G. Tambouratzis In this article, two clustering techniques based on neural networks are introduced. The two neural network models are the Harmony theory network (HTN) and the self-organizing logic neural network (SOLNN), both of which are characterized by parallel processing, a distributed architecture, and a large number of nodes. After describing their clustering characteristics and potential, a comparison to classical statistical techniques is performed. This comparison allows the creation of a correspondence between each neural network clustering technique and particular metrics as used by the corresponding statistical methods, which reflect the affinity of the clustered patterns. In particular, the HTN is found to perform the clustering task with an accuracy similar to the best statistical methods, while it is further capable of proposing an optimal number of groups into which the patterns may be clustered. On the other hand, the SOLNN combines a high clustering accuracy with the ability to cluster higher-dimensional patterns without a considerable increase in the processing time. © 2003 Wiley Periodicals, Inc. [source] Testing alternate ecological approaches to seagrass rehabilitation: links to life-history traitsJOURNAL OF APPLIED ECOLOGY, Issue 5 2010Andrew D. Irving Summary 1.,Natural resources and ecosystem services provided by the world's major biomes are increasingly threatened by anthropogenic impacts. Rehabilitation is a common approach to recreating and maintaining habitats, but limitations to the success of traditional techniques necessitate new approaches. 2.,Almost one-third of the world's productive seagrass meadows have been lost in the past 130 years. Using a combined total of three seagrass species at seven sites over 8 years, we experimentally assessed the performance of multiple rehabilitation methods that utilize fundamentally different ecological approaches. 3.,First, traditional methods of transplantation were tested and produced varied survival (0,80%) that was site dependent. Secondly, seedling culture and outplanting produced poor survival (2,9%) but reasonable growth. Finally, a novel method that used sand-filled bags of hessian to overcome limitations of traditional techniques by facilitating recruitment and establishment of seedlings in situ produced recruit densities of 150,350 seedlings m,2, with long-term survival (up to 38 months) ranging from 0 to 72 individuals m,2. 4.,Results indicate that facilitating seagrass recruitment in situ using hessian bags can provide a new tool to alleviate current limitations to successful rehabilitation (e.g. mobile sediments, investment of time and resources), leading to more successful management and mitigation of contemporary losses. Hessian bags have distinct environmental and economic advantages over other methods tested in that they do not damage existing meadows, are biodegradable, quick to deploy, and cost less per hectare (US$16 737) than the estimated ecosystem value of seagrass meadows (US$27 039 year,1). 5.,Synthesis and applications. This research demonstrates how exploring alternate ecological approaches to habitat rehabilitation can expand our collective toolbox for successfully re-creating complex and productive ecosystems, and alleviate the destructive side-effects and low success rates of more traditional techniques. Moreover, new methods can offer economic and environmental solutions to the restrictions placed upon managers of natural resources. [source] Comparison of the specificity and sensitivity of traditional methods for assessment of nephrotoxicity in the rat with metabonomic and proteomic methodologiesJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2005Andy Gibbs Abstract There is currently a great deal of scientific interest and debate concerning the possible advantages that proteomic and metabonomic technologies might have over traditional biomarkers of toxicity (blood and urine chemistry, histopathology). Numerous papers have been published that make impressive claims concerning potential applications for these novel technologies, however there appears to be little hard evidence in the literature of their advantages over the traditional techniques for assessing toxicity. The aim of this review was to evaluate the relative sensitivity and specificity of proteomic and metabonomic techniques, compared with traditional techniques, for assessing xenobiotic-induced nephrotoxicity. A review of studies was performed where both one of the novel methods as well as traditional techniques were used for assessment of xenobiotic-induced nephrotoxicity. There was no consistent evidence from the literature that the novel methodologies were any more sensitive than the traditional methods for assessing nephrotoxicity. This could be due to the relatively small number of studies available for review (n = 13), the fact that generally these studies were not aimed at determining relative sensitivity or specificity and may not be the case with other target organs, such as the liver. However, it was clear that the novel methodologies were able to discriminate between the effects caused by different toxicants. There was evidence both that this discrimination was on the basis of different mechanisms of toxicity and on the basis of different locations of nephrotoxic lesion. A great deal of validation work is necessary before these techniques could gain full acceptance by regulatory authorities, and it is unclear whether their use in anything other than non-regulatory, mechanistic studies is likely to become widespread. Copyright © 2005 John Wiley & Sons, Ltd. [source] Perioperative myocardial infarction in noncardiac surgery: the diagnostic and prognostic role of cardiac troponinsJOURNAL OF INTERNAL MEDICINE, Issue 1 2002S. LUCREZIOTTI Abstract.,Lucreziotti S, Foroni C, Fiorentini C (Università degli Studi di Milano, Ospedale S. Pado, Milano, Italy). Perioperative myocardial infarction in noncardiac surgery: the diagnostic and prognostic role of cardiac troponins (Review). J Intern Med 2002; 252: 11,20. Despite the number of technologies used, the diagnosis of perioperative myocardial infarction is still a challenge. Studies conducted in surgical series have demonstrated that cardiac troponins (cTns) have both a superior diagnostic sensitivity and specificity, compared with other traditional techniques, and an independent power to predict short- and long-term prognosis. Nevertheless, some points need to be clarified. They include the usefulness of cTns in patients with end-stage renal failure; the standardization of the cTns cut-off for the diagnosis of myocardial injury; the timing of postoperative blood samplings; the cost-effectiveness of a screening in asymptomatic patients; and the possible therapeutic strategies. [source] Use of micro-Raman spectroscopy to study reaction kinetics in blended white cement pastes containing metakaolinJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2009Moisés Frías Abstract Curing temperature is known to play an important role in the formation, development, and stability of the hydrated phases appearing during pozzolanic reactions (chemical reaction between puzzolanic addition, metakaolin (MK), and calcium hydroxide from cement hydration). A typical example of this important reaction is to be found in metakaolin-bearing cement pastes, characterized by hexagonal phases whose thermodynamic stability declines with rising temperature. These phases cannot be exhaustively researched with traditional techniques (such as X-ray diffraction) due to their poor crystallinity. Consequently, micro-Raman spectroscopy was used in the present study to explore the behavior of white cement paste blends containing 0, 10, and 25% MK at two curing temperatures (20 and 60 °C). This led to the identification, for the first time using Raman spectroscopy, of phases C2ASH81 (stratlingite) and C3ASH6, which appear in the MK,white cement reaction. The CSH gel formed was characterized by Q1 dimers and a C/S ratio of 1.3,1.5. Raising the curing temperature favored the formation of C4AH13. Copyright © 2009 John Wiley & Sons, Ltd. [source] Experimental and statistical analysis methods for peptide detection using surface-enhanced Raman spectroscopyJOURNAL OF RAMAN SPECTROSCOPY, Issue 3 2008Breeana L. Mitchell Abstract Surface-enhanced Raman spectroscopy (SERS) has the potential to make a significant impact in biology research due to its ability to provide information orthogonal to that obtained by traditional techniques such as mass spectrometry (MS). While SERS has been well studied for its use in chemical applications, detailed investigations with biological molecules are less common. In addition, a clear understanding of how methodology and molecular characteristics impact the intensity, the number of peaks, and the signal-to-noise of SERS spectra is largely missing. By varying the concentration and order of addition of the SERS-enhancer salt (LiCl) with colloidal silver, we were able to evaluate the impact of these variables on peptide spectra using a quantitative measure of spectra quality based on the number of peaks and peak intensity. The LiCl concentration and order of addition that produced the best SERS spectra were applied to a panel of synthetic peptides with a range of charges and isoelectric points (pIs) where the pI was directly correlated with higher spectral quality. Those peptides with moderate to high pIs and spectra quality scores were differentiated from each other using the improved method and a hierarchical clustering algorithm. In addition, the same method and algorithm was applied to a set of highly similar phosphorylated peptides, and it was possible to successfully classify the majority of peptides on the basis of species-specific peak differences. Copyright © 2008 John Wiley & Sons, Ltd. [source] IMPACT OF MICROWAVE BLANCHING ON THE FLAVOR OF ROASTED PEANUTSJOURNAL OF SENSORY STUDIES, Issue 4 2006ANDRIANA V. SCHIRACK ABSTRACT Microwave blanching of peanuts was proposed as an attractive alternative to traditional techniques of blanching, because of energy and time savings. However, the occurrence of a processing-related off-flavor has been reported. This study examined the effect of processing factors during microwave blanching on the MC and sensory characteristics of the peanuts. The peanuts reached a range of internal temperatures during microwave blanching treatments between 4 and 11 min. A total offnote attribute was introduced to the peanut lexicon and was used successfully to differentiate the effects of microwave treatments. The microwave-associated off-flavor was related (but not identical) to cardboardy/stale flavor, and was related inversely to the positive flavor attributes roasted peanutty, sweet aromatic and sweet taste. Peanuts reaching the highest internal temperatures and greatest moisture losses during blanching exhibited the most total offnote flavor; however, temperatures as high as 113C did not produce significantly increased total offnote intensity. [source] From Chelating Precursor to Perovskite Oxides and Hollow Fiber MembranesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2007S. Liu Perovskite Ba0.5Sr0.5Co0.8Fe0.2O3-, (BSCF) is a promising mixed-conducting ceramic membrane material in addition to being a good electrode catalyst for solid oxide fuel cells. In this study, BSCF powder was synthesized via a chelated water-soluble complex method at relatively low temperatures. The combined ethylenediaminetetraacetic acid and citric acid was used for the synthesis of a complex-based precursor, followed by thermal decomposition of the precursor at high temperatures. Thermal behavior, crystal phases, and structures of the prepared powders were characterized by thermogravimetric analysis/differential scanning calorimetry, XRD, and scanning electron microscopic (SEM) techniques, respectively. Pure and single-phase perovskite could be obtained after sintering at a temperature higher than 800°C for 5 h. The soft precursor powder synthesized at lower temperatures, i.e., 600°C, is water insoluble and more appropriate for use as a membrane material to prepare gas-tight tubular or hollow fiber ceramic membranes. By contrast, the hollow fibers prepared via the traditional techniques where the perovskite powder is used as the starting membrane materials display gas leakage. The fibers were characterized by SEM, XRD, and tested for air separation at ambient pressure and temperatures between 700° and 950°C. The oxygen flux measured in this work reached 3.90 mL·(min·cm2),1 and compares favorably with any experimental values reported in the open literature. [source] Aqueous two-phase systems strategies for the recovery and characterization of biological products from plantsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 9 2010Oscar Aguilar Abstract The increasing interest of the biopharmaceutical industry to exploit plants as economically viable production systems is demanding the development of new downstream strategies to maximize product recovery. Aqueous two-phase systems (ATPSs) are a primary recovery technique that has shown great potential for the efficient extraction and purification of biological compounds. The present paper gives an overview of the efficient use of ATPS-based strategies for the isolation and partial purification of bioparticles from plant origin. Selected examples highlight the main advantages of this technique, i.e. scaling-up feasibility, process integration capability and biocompatibility. An overview of the recent approach of coupling ATPSs with traditional techniques to increase bioseparation process performance is discussed. A novel approach to characterization protein from plants combining ATPSs and two-dimensional electrophoresis (2-DE) is introduced as a tool for process development. In the particular case of products from plant origin, early success has demonstrated the potential application of ATPS-based strategies to address the major disadvantages of the traditional recovery and purification techniques. This literature review discloses the relevant contribution of ATPSs to facilitate the establishment of bioprocesses in the growing field of high-value products from plants. Copyright © 2010 Society of Chemical Industry [source] Development of electronic nose method for evaluation of residual solvents in low-density polyethylene films ,PACKAGING TECHNOLOGY AND SCIENCE, Issue 2 2007Isinay E. Yüzay Abstract Flexible packaging films containing high levels of residual volatile organic compounds (VOCs) can alter the flavour and odour of packaged foods. Currently, a range of gas chromatographic techniques and sensory evaluations are used for assessing the residual VOCs in packaging films. An objective method for assessing the residual solvents from low-density polyethylene (LDPE) was developed using an Alpha MOS Fox 3000 electronic nose (e-nose) equipped with 12 metal oxide semiconductor sensors. Three VOCs, ethyl acetate, ethyl alcohol and toluene, were chosen as models for solvents of interest in flexible food packaging analysis. LDPE film samples were spiked with single and binary mixtures of solvents and analysed using the e-nose and by GC,FID (HP 6890; Hewlett-Packard Co., Wilmington, DE). The responses obtained from the e-nose were processed using principal component analysis (PCA) and discriminate factorial analysis (DFA) in order to identify the residual solvents. Partial least squares analysis (PLS) was also used to quantify the amount of residual solvent and to correlate the e-nose results with gas chromatography, which is currently the standard method for determining residual VOCs in packaging films. There was good agreement between the e-nose responses and gas chromatography results for single solvents (r = 0.90,0.98). The technique also worked for binary solvent mixtures (r = 0.84,0.99). The electronic nose can be a viable alternative to traditional techniques while providing simplicity and objectivity, which would be extremely advantageous in routine quality control of residual solvents. Copyright © 2006 John Wiley & Sons, Ltd. [source] Electronic properties and phase transitions in Si, ZnSe, and GaAs under pressure cycling up to 20,30 GPa in a high-pressure cellPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 3 2009Sergey V. Ovsyannikov Abstract An automated high-pressure setup employing anvil-type cells is applied for investigation of phase transitions and elec- tronic properties (the thermoelectric power (Seebeck effect), the electrical resistivity) of silicon, zinc selenide and gal lium arsenide under pressure cycling within the range of 0,20(30) GPa. The "correlation" dependencies of a pressure value of the semiconductor,metal transition in Czochralski-grown silicon (Cz-Si) on the concentrations of both carriers and residual interstitial oxygen are discussed. In all Si samples a decompression of the high-pressure metal phase produces the semimetal p-type phases: the rhombohedral r8 (Si-XII) and the body-centred cubic bc8 (Si-III) lattices. Re- pressurization cycles reveal two features in the semimetal phase, near 2 GPa and 5 GPa. The transitions into the metal phase at higher pressure resemble those in pristine silicon. For ZnSe and GaAs, it is found that decompression from the high-pressure phases (NaCl and Cmcm, respectively) can follow different paths, producing the zincblende, the cinnabar and the wurtzite lattices. Advantages of the characterization method are discussed, in comparison with both the traditional techniques (X-ray diffraction, Raman spectroscropy, etc.) and the more recent ones (such as nanoindentation). (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] VII,The Bayesian and the DogmatistPROCEEDINGS OF THE ARISTOTELIAN SOCIETY (HARDBACK), Issue 1pt2 2007Brian Weatherson It has been argued recently that dogmatism in epistemology is incompatible with Bayesianism. That is, it has been argued that dogmatism cannot be modelled using traditional techniques for Bayesian modelling. I argue that our response to this should not be to throw out dogmatism, but to develop better modelling techniques. I sketch a model for formal learning in which an agent can discover a posteriori fundamental epistemic connections. In this model, there is no formal objection to dogmatism. [source] Crucial stages of protein folding through a solvable model: Predicting target sites for enzyme-inhibiting drugsPROTEIN SCIENCE, Issue 8 2002Cristian Micheletti Abstract An exactly solvable model based on the topology of a protein native state is applied to identify bottlenecks and key sites for the folding of human immunodeficiency virus type 1 (HIV-1) protease. The predicted sites are found to correlate well with clinical data on resistance to Food and Drug Administration-approved drugs. It has been observed that the effects of drug therapy are to induce multiple mutations on the protease. The sites where such mutations occur correlate well with those involved in folding bottlenecks identified through the deterministic procedure proposed in this study. The high statistical significance of the observed correlations suggests that the approach may be promisingly used in conjunction with traditional techniques to identify candidate locations for drug attacks. [source] Technical note: A new method for measuring long bone curvature using 3D landmarks and semi-landmarksAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 4 2010Isabelle De Groote Abstract Here we describe and evaluate a new method for quantifying long bone curvature using geometric morphometric and semi-landmark analysis of the human femur. The technique is compared with traditional ways of measuring subtense and point of maximum curvature using either coordinate calipers or projection onto graph paper. Of the traditional methods the graph paper method is more reliable than using coordinate calipers. Measurement error is consistently lower for measuring point of maximum curvature than for measuring subtense. The results warrant caution when comparing data collected by the different traditional methods. Landmark data collection proves reliable and has a low measurement error. However, measurement error increases with the number of semi-landmarks included in the analysis of curvature. Measurements of subtense can be estimated more reliably using 3D landmarks along the curve than using traditional techniques. We use equidistant semi-landmarks to quantify the curve because sliding the semi-landmarks masks the curvature signal. Principal components analysis of these equidistant semi-landmarks provides the added benefit of describing the shape of the curve. These results are promising for functional and forensic analysis of long bone curvature in modern human populations and in the fossil record. Am J Phys Anthropol, 2010. © 2010 Wiley-Liss, Inc. [source] Highly efficient and selective enrichment of peptide subsets combining fluorous chemistry with reversed-phase chromatographyRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 24 2009Wantao Ying The selective capture of target peptides poses a great challenge to modern chemists and biologists, especially when enriching them from proteome samples possessing extremes in concentration dynamic range and sequence diversity. While approaches based on traditional techniques such as biotin-avidin pairing offer versatile tools to design strategies for selective enrichment, problems are still encountered due to sample loss or poor selectivity of enrichment. Here we show that the recently introduced fluorous chemistry approach has attractive properties as an alternative method for selective enrichment. Through appending a perfluorine group to the target peptide, it is possible to dramatically increase the peptide's hydrophobicity and thus enable facile separation of labeled from non-labeled peptides. Use of reversed-phase chromatography allowed for improved peptide recovery in comparison with results obtained using the formerly reported fluorous bonded phase methods. Furthermore, this approach also allowed for on-line separation and identification of both labeled and unlabeled peptides in a single experiment. The net result is an increase in the confidence of protein identification by tandem mass spectrometry (MS2) as all peptides and subsequent information are retained. Successful off-line and on-line enrichment of cysteine-containing peptides was obtained, and high quality MS2 spectra were obtained by tandem mass spectrometry due to the stability of the tag, allowing for facile identification via standard database searching. We believe that this strategy holds great promise for selective enrichment and identification of low abundance target proteins or peptides. Copyright © 2009 John Wiley & Sons, Ltd. [source] Cartilage tympanoplasty: Indications, techniques, and outcomes in A 1,000-patient seriesTHE LARYNGOSCOPE, Issue 11 2003John Dornhoffer MD Abstract Objectives/Hypothesis: The purpose of this study was to analyze the anatomical and audiologic results in more than 1,000 cartilage tympanoplasties that utilized a logical application of several techniques for the management of the difficult ear (cholesteatoma, recurrent perforation, atelectasis). Our hypothesis was that pathology and status of the ossicular chain should dictate the technique used to achieve optimal outcome. Study Design: Retrospective clinical study of patients undergoing cartilage tympanoplasty between July 1994 and July 2001. A computerized otologic database and patient charts were used to obtain the necessary data. Methods: A modification of the perichondrium/cartilage island flap was utilized for tympanic membrane reconstruction in cases of the atelectatic ear, for high-risk perforation in the presence of an intact ossicular chain, and in association with ossiculoplasty when the malleus was absent. A modification of the palisade technique was utilized for TM reconstruction in cases of cholesteatoma and in association with ossiculoplasty when the malleus was present. Hearing results were reported using a four-frequency (500, 1,000, 2,000, 3,000 Hz) pure-tone average air-bone gap (PTA-ABG). The Student t test was used for statistical comparison. Postoperative complications were recorded. Results: During the study period, cartilage was used for TM reconstruction in more than 1,000 patients, of which 712 had sufficient data available for inclusion. Of these, 636 were available for outcomes analysis. In 220 cholesteatoma cases, the average pre- and postoperative PTA-ABGs were 26.5 ± 12.6 dB and 14.6 ± 8.8 dB, respectively (P < .05). Recurrence was seen in 8 cases (3.6%), conductive HL requiring revision in 4 (1.8%), perforation in 3 (1.4%), and postand intraoperative tube insertion in 11 (5.0%) and 18 ears (8.2%), respectively. In 215 cases of high-risk perforation, the average pre- and postoperative PTA-ABGs were 21.7 ± 13.5 dB and 11.9 ± 9.3 dB, respectively (P < .05). Complications included recurrent perforation in 9 ears (4.2%), conductive HL requiring revision in 4 (1.9%), postoperative and intraoperative tube insertion in 4 (1.9%) and 6 ears (2.8%), respectively. In 98 cases of atelectasis, the average pre- and postoperative PTA-ABGs were 20.2 ± 10.9 dB and 14.2 ± 10.2 dB, respectively (P < .05). Complications included 1 perforation (1.0%), conductive loss requiring revision in 2 cases (2.0%), and post- and intraoperative tube insertion in 7 (7.1%) and 12 ears (12%), respectively. In 103 cases to improve hearing (audiologic), the average pre- and postoperative PTA-ABGs were 33.6 ± 9.6 dB and 14.6 ± 10.1 dB, respectively (P < .05). Complications included 1 perforation (1.0%), conductive loss requiring revision in 11 (11%), and post- and intraoperative tube insertion in 6 (5.8%) and 2 (1.9%), respectively. Conclusions: Cartilage tympanoplasty achieves good anatomical and audiologic results when pathology and status of the ossicular chain dictate the technique utilized. Significant hearing improvement was realized in each pathological group. In the atelectatic ear, cartilage allowed us to reconstruct the TM with good anatomic results compared to traditional reconstructions, which have shown high rates of retraction and failure. In cholesteatoma, cartilage tympanoplasty using the palisade technique resulted in precise reconstruction of the TM and helped reduce recurrence. In cases of high-risk perforation, reconstruction with cartilage yielded anatomical and functional results that compared favorably to primary tympanoplasty using traditional techniques. We believe the indications for cartilage tympanoplasty (atelectatic ear, cholesteatoma, high-risk perforation) were validated by these results. [source] Neurological complication analysis of 1000 ultrasound guided peripheral nerve blocks for elective orthopaedic surgery: a prospective study,ANAESTHESIA, Issue 8 2009M. J. Fredrickson Summary Little data exists regarding the frequency of neurological complications following ultrasound guided peripheral nerve blockade. Therefore, we studied single injection and continuous ultrasound guided interscalene, supraclavicular, infraclavicular, femoral and sciatic nerve blocks in patients undergoing orthopaedic extremity surgery. All patients were contacted during postoperative weeks 2,4 and questioned for numbness or altered sensation anywhere in the involved extremity, and pain or weakness unrelated to surgery. The presumed aetiology of symptoms was based on the collective agreement of principal investigator, primary surgeon and a neurologist. Multivariate analysis was performed for characteristics potentially important in the causation of neurological complications. Of 1010 consecutive blocks, successful follow up between weeks 2 and 4 occurred in 98.6%. New, all-cause, neurological symptoms were present in 56/690 blocks (8.2%) at day 10, 37/1010 (3.7%) at 1 month and 6/1010 (0.6%) at 6 months. Most symptoms were due to causes unrelated to the block. Of 452 patients directly questioned at the time of the block, new neurological symptoms were more common in patients who experienced procedure-induced paraesthesia (odds ratio = 1.7, p = 0.029). The postoperative neurological symptom rate in this series is very similar to those previously reported following traditional techniques. [source] Detection of possible archaeological pathways in central Mexico through digital processing of remote sensing imagesARCHAEOLOGICAL PROSPECTION, Issue 2 2005Denisse Argote-Espino Abstract Many spaceborne multispectral images have been developed recently and applied in archaeology as they provide useful data, which can be digitized, manipulated and integrated. Principal component decomposition (PCD), texture segmentation and linear pattern detection through spatial filtering are useful techniques that provide a new way of processing satellite images in addition to traditional techniques. Such methods may supply more accurate information of an area, in particular a region of archaeological interest. In this paper we applied a new alternative method based on the techniques mentioned above to an important area of central Mexico. The region of study is located to the southwest of Las Cruces Range between the Mexico Basin and the Toluca Valley. Processing a multispectral image from that area, it was possible to detect possible communication corridors, which provided cultural and commercial linking to the ancient settlers of both adjacent basins. This information is very important for understanding the way these people interacted in the past and the commercial importance that could exist between them. Copyright © 2005 John Wiley & Sons, Ltd. [source] Tree crop smallholders, capitalism, and adat: Studies in Riau Province1, IndonesiaASIA PACIFIC VIEWPOINT, Issue 3 2004Lesley Potter Abstract:,This paper examines the extent to which traditional techniques and practices remain current among a sub-set of Indonesian tree crop smallholders. Village-based studies of independent oil palm and rubber smallholders in Riau (Sumatra) indicate that bio-diverse ,jungle rubber' and multi-cropping techniques still exist, but primarily as components of farmers' coping strategies under low commodity prices. A further strategy, seeking income from non-agrarian sources, notably ,illegal' logging and land sales to migrants, partially fits Rigg's ,deagrarianisation' thesis, though his suggestion that the farm household has become a mere ,shell' is not substantiated. The lack of full legalisation of tenure constrains full capitalist development but does not impede land sales. Land seizures during the Suharto period reduced belief in the efficacy of customary (adat) law, though adat has retained importance in dispute resolution and as a cultural framework. New structures of village governance following decentralisation have so far had minimal impact in either empowering villagers or dispossessing elites. [source] Precipitants and additives for membrane crystallization of lysozymeBIOTECHNOLOGY JOURNAL, Issue 11 2006Xinmiao Zhang Abstract Membrane crystallization is a newly developed crystallization technique that has proven to be superior in producing good crystal forms under operating conditions that are not appropriate to perform the crystallization process by other traditional techniques. In this work, static membrane crystallization was carried out on lysozyme, with hollow-fiber microporous hydrophobic membranes. Numerous precipitant and additive types and concentrations were employed in the crystallization processes in order to select the most appropriate precipitant and additive types and to find their corresponding concentration levels that can yield the best crystal forms. The crystallization processes were analyzed in two ways: firstly, by evaluation of the transmembrane fluxes obtained by using different precipitants and additives; secondly, by utilization of the images and results obtained from the micrography and IR spectra in comparisons and evaluations of the crystals formed under all kinds of conditions. Moreover, the size distributions of the crystals yielded under several typical crystallization conditions were analyzed, and turbidity and induction time periods obtained during typical crystallization experiments were also measured. Amongst the numerous precipitants and additives tested, the most appropriate precipitant type and additive were chosen and their concentrations were optimized. Good lysozyme crystals were obtained using a certain precipitant and additive. The obtained results from this work further support the advantages of utilizing the membrane crystallization technique for macromolecule crystallizations. [source] Progress technology in microencapsulation methods for cell therapyBIOTECHNOLOGY PROGRESS, Issue 4 2009Jean-Michel Rabanel Abstract Cell encapsulation in microcapsules allows the in situ delivery of secreted proteins to treat different pathological conditions. Spherical microcapsules offer optimal surface-to-volume ratio for protein and nutrient diffusion, and thus, cell viability. This technology permits cell survival along with protein secretion activity upon appropriate host stimuli without the deleterious effects of immunosuppressant drugs. Microcapsules can be classified in 3 categories: matrix-core/shell microcapsules, liquid-core/shell microcapsules, and cells-core/shell microcapsules (or conformal coating). Many preparation techniques using natural or synthetic polymers as well as inorganic compounds have been reported. Matrix-core/shell microcapsules in which cells are hydrogel-embedded, exemplified by alginates capsule, is by far the most studied method. Numerous refinement of the technique have been proposed over the years such as better material characterization and purification, improvements in microbead generation methods, and new microbeads coating techniques. Other approaches, based on liquid-core capsules showed improved protein production and increased cell survival. But aside those more traditional techniques, new techniques are emerging in response to shortcomings of existing methods. More recently, direct cell aggregate coating have been proposed to minimize membrane thickness and implants size. Microcapsule performances are largely dictated by the physicochemical properties of the materials and the preparation techniques employed. Despite numerous promising pre-clinical results, at the present time each methods proposed need further improvements before reaching the clinical phase. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Clinical application of the multifocal visual evoked potentialCLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 3 2004David P. Crewther PhD Background: Measures of visual function thresholds such as visual acuity and visual fields are generally dependent on subjective responses and assume maintenance of fixation, attention and motivation. In the young, elderly, cognitively impaired or malingering populations, such measures may be inaccurate or difficult to obtain. The Visual Evoked Response Imaging System (VERIS) has been claimed to give more objective topographic recordings of retinal and cortical function. This paper aims to explore the adequacy of this technique in four unusual, unrelated, clinically difficult cases. Methods: Multifocal visual evoked potentials (mfVEPs) recorded on the VERIS System 3.01 are used to assess visual function in four cases with contradictory clinical findings or unreliable subjective responses. Results: Patient 1 had sustained a head injury and had normal ocular and pupil examination but light perception in the right eye and 6/5 acuity in the left. Multifocal VEPs showed a marked depression of the right visual field with little macular response. Patient 2 had sustained a head injury, had a left field hemianopia, possible macular sparing and loss of much of the right field, reduced but variable visual acuities, good near vision and normal ocular fundi. Multifocal VEPs showed a severe depression in both visual fields (L more than R) with little macular response. Patient 3 had a left optic nerve meningioma and experienced great difficulty with visual field assessment. mfVEPs showed a bilateral depression in the superior field particularly the left field, with a larger deficit in the left eye. Patient 4 had unexplained visual acuity and peripheral field deficits. mfVEP results were inconclusive in this case. Discussion: Where there is difficulty performing traditional techniques or conflicting clinical findings, mfVEPs may provide additional objective information to aid in the assessment of patients. [source] | |||||||||||||||||||||||||