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Kinds of Method Terms modified by Method Selected AbstractsA NEW METHOD FOR STUDYING THE EXTENT, STABILITY, AND PREDICTORS OF INDIVIDUAL SPECIALIZATION IN VIOLENCE,CRIMINOLOGY, Issue 2 2007D. WAYNE OSGOOD Specialization in violence is an important scientific and policy topic, and over the past several decades, many analysis techniques for studying specialization have emerged. Research in this area continues to be hampered, however, by remaining methodological problems. To overcome these problems, we propose a new method for studying specialization in violence based on an item-response theory measurement approach that is implemented through a multilevel regression model. Our approach defines specialization as an individual level latent variable, takes into account the inherent confounds between specialization and overall level of offending, and gauges specialization relative to the population base rates of each offense. Our method also enables researchers to 1) estimate the extent and statistical significance of specialization, 2) assess the stability of specialization over time, and 3) relate specialization to explanatory variables. Using data from three studies, we found substantial levels of specialization in violence, considerable stability in specialization over time, and several significant and relatively consistent relationships of specialization to explanatory variables such as gender, parental education, and risk-seeking. [source] THE INTERACTION OF ANTISOCIAL PROPENSITY AND LIFE-COURSE VARYING PREDICTORS OF DELINQUENT BEHAVIOR: DIFFERENCES BY METHOD OF ESTIMATION AND IMPLICATIONS FOR THEORY,CRIMINOLOGY, Issue 2 2007GRAHAM C. OUSEY Recent criminological research has explored the extent to which stable propensity and life-course perspectives may be integrated to provide a more comprehensive explanation of variation in individual criminal offending. One line of these integrative efforts focuses on the ways that stable individual characteristics may interact with, or modify, the effects of life-course varying social factors. Given their consistency with the long-standing view that person,environment interactions contribute to variation in human social behavior, these theoretical integration attempts have great intuitive appeal. However, a review of past criminological research suggests that conceptual and empirical complexities have, so far, somewhat dampened the development of a coherent theoretical understanding of the nature of interaction effects between stable individual antisocial propensity and time-varying social variables. In this study, we outline and empirically assess several of the sometimes conflicting hypotheses regarding the ways that antisocial propensity moderates the influence of time-varying social factors on delinquent offending. Unlike some prior studies, however, we explicitly measure the interactive effects of stable antisocial propensity and time-varying measures of selected social variables on changes in delinquent offending. In addition, drawing on recent research that suggests that the relative ubiquity of interaction effects in past studies may be partly from the poorly suited application of linear statistical models to delinquency data, we alternatively test our interaction hypotheses using least-squares and tobit estimation frameworks. Our findings suggest that method of estimation matters, with interaction effects appearing readily in the former but not in the latter. The implications of these findings for future conceptual and empirical work on stable propensity/time-varying social variable interaction effects are discussed. [source] SEDUCTIONS OF METHOD: REJOINDER TO NAGIN AND TREMBLAY'S "DEVELOPMENTAL TRAJECTORY GROUPS: FACT OR FICTION?",CRIMINOLOGY, Issue 4 2005ROBERT J. SAMPSON [source] Nonvisible Insufficient Subcutaneous Reticular Venous Plexus Can Be Observed through the Skin Using a New Illumination MethodDERMATOLOGIC SURGERY, Issue 2010LUIS LOPEZ BUSTOS MD BACKGROUND Insufficient subcutaneous reticular venous plexus (ISRVP) is an overlooked disease because the human eye cannot see many of the insufficient veins. OBJECTIVE To present a total reticular vision (TRV) method that exposes nonvisible ISRVP to normal vision. METHOD & MATERIALS TRV used visual-spectrum white and red light of 700 nm and infrared light of 15 to 850 nm from an ultradigital viewer camera. We studied 124 asymptomatic subjects from the general population without visible ISRVP. Another six patients with ISRVP without other venous pathology were compared with six healthy controls, Very low pressure was applied to the proximal thigh, and minimal volume increments on the medial malleolus were photoplethysmographically registered to validate subcutaneous venous reflux. RESULTS Total reticular vision exposed ISRVP on the lower extremities in 72 of 124 subjects (58%), with observed damaged veins corresponding to more than 90% of nonvisible and 5% of visible portions of ISRVP. Subcutaneous reflux was registered only in patients with ISRVP. CONCLUSION Total reticular vision exposed more than 90% of nonvisible ISRVP, a new pathology, allowing for the study of its relationship with other superficial venous insufficiencies. The authors have indicated no significant interest with commercial supporters. [source] PROPHYLACTIC PANCREAS STENTING FOLLOWED BY NEEDLE-KNIFE FISTULOTOMY IN PATIENTS WITH SPHINCTER OF ODDI DYSFUNCTION AND DIFFICULT CANNULATION: NEW METHOD TO PREVENT POST-ERCP PANCREATITISDIGESTIVE ENDOSCOPY, Issue 1 2009László Madácsy Introduction:, The aim of the present study was to reduce post-endoscopic retrograde cholangiopancreatography (ERCP) complications with a combination of early needle-knife access fistulotomy and prophylactic pancreatic stenting in selected high-risk sphincter of Oddi dysfunction (SOD) patients with difficult cannulation. Methods:, Prophylactic pancreatic stent insertion was attempted in 22 consecutive patients with definite SOD and difficult cannulation. After 10 min of failed selective common bile duct cannulation, but repeated (>5×) pancreatic duct contrast filling, a prophylactic small calibre (3,5 Fr) pancreatic stent was inserted, followed by fistulotomy with a standard needle-knife, then a standard complete biliary sphincterotomy followed. The success and complication rates were compared retrospectively with a cohort of 35 patients, in which we persisted with the application of standard methods of cannulation without pre-cutting methods. Results:, Prophylactic pancreatic stenting followed by needle-knife fistulotomy was successfully carried out in all 22 consecutive patients, and selective biliary cannulation and complete endoscopic sphincterotomy were achieved in all but two cases. In this group, not a single case of post-ERCP pancreatitis was observed, in contrast with a control group of three mild, 10 moderate and two severe post-ERCP pancreatitis cases. The frequency of post-ERCP pancreatitis was significantly different: 0% versus 43%, as were the post-procedure (24 h mean) amylase levels: 206 U/L versus 1959 U/L, respectively. Conclusions:, In selected, high-risk, SOD patients, early, prophylactic pancreas stent insertion followed by needle-knife fistulotomy seems a safe and effective procedure with no or only minimal risk of post-ERCP pancreatitis. However, prospective, randomized studies are awaited to lend to support to our approach. [source] COLLAPSE-SUBMERGENCE METHOD: SIMPLE COLONOSCOPIC TECHNIQUE COMBINING WATER INFUSION WITH COMPLETE AIR REMOVAL FROM THE RECTOSIGMOID COLONDIGESTIVE ENDOSCOPY, Issue 1 2007Takeshi Mizukami Colonoscopy is a difficult examination to conduct for inexperienced examiners. In an attempt to improve the view, there is often a tendency to overinsufflate air, which causes elongation or acute angulations of the colon and makes passage of the scope difficult. Sakai et al. were the first to describe a simple colonoscopic technique using water infusion instead of air insufflation. We have modified this technique to simplify the procedure further by combining water infusion using disposable syringes with complete air suction from the rectum to the descending colon. With the resultant elimination of the boundary lines between water and air, a good view of the lumen is obtained though the transparent water. With the patient in the left lateral position, this procedure allows the water to flow straight down into the descending colon through the ,collapsed' lumen, and the scope to be easily negotiated through the straightened recto-sigmoid colon and sigmoid-descending colon junction with minimum discomfort. Measurements of the patients' abdominal circumference during colonoscopy showed that colonic distension hardly occurred. Under supervision by the author, six complete novices were allowed to insert the colonoscope within 10 min by this method for one patient per week, as long as the patients did not complain of pain. The average trial number for the first cecal intubation within 10 min was 3.3, and the average success rate during the first 3 months was 58.6%. We believe that this ,collapse-submergence method' is easy to master, even for inexperienced examiners. [source] ENDOSCOPIC MUCOSAL RESECTION AND SUBMUCOSAL DISSECTION METHOD FOR LARGE COLORECTAL TUMORSDIGESTIVE ENDOSCOPY, Issue 2004Yasushi Sano ABSTRACT The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation-tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT-knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms. [source] THE TECHNICAL FUNDAMENTALS OF ENDOSCOPIC MUCOSAL RESECTION IN THE COLON: OUR METHODDIGESTIVE ENDOSCOPY, Issue 2004Yasushi Oda ABSTRACT Endoscopic mucosal resection (EMR) is the technique used to resect flat or depressed tumors or larger tumors such as laterally spreading tumors with marginal normal mucosa. Recently, endoscopic mucosal dissection technique has been rapidly accepted, mainly in early gastric cancer in Japan. We need to have firm knowledge of EMR technique in the colon for recovery as we advance this new technique. We describe our conventional EMR method practically. EMR should be performed to locate the target lesion at down side to perform sure EMR. The ideal shape of upheaval by saline injection is hemisphere. The needle sheath and snare should be taken out a little of the endoscopy to manipulate firmly. Another technique of secure EMR is the snare manipulation. We prefer that the shape of the snare is circular and the snare is hard. It is important while trapping to press the target lesion with both the whole snare circle and the end of the sheath. With these fundamental procedures we could resect the target lesions at will. [source] MODIFIED ENDOSCOPIC CONGO RED TEST: A RAPID METHOD TO VISUALIZE GASTRIC ACID SECRETIONDIGESTIVE ENDOSCOPY, Issue 1 2003Ervin Tóth Background:, The conventional endoscopic Congo red test (CRT) permits visualization of acid-producing mucosa. However, the CRT has not been disseminated into clinical endoscopy, which is partly due to the substantial prolongation of the gastroscopic examination. Methods:, Five healthy volunteers and 551 patients were included in a study designed to develop a more rapid approach based on the CRT. In this modified endoscopic Congo red test (MCRT), 0.2 µg/kg of pentagastrin was given intravenously to stimulate gastric acid production. The technical feasibility, tolerability, reproducibility, and inter- and intra-observer reliability of the MCRT were evaluated. Results:, The MCRT was as effective as the CRT (i.e. 6 µg/kg of pentagastrin was administered intramuscularly) in visualizing the extent of acid-producing gastric mucosa. Moreover, the MCRT significantly reduced the duration of examination by 63% (almost 8 min), compared to the CRT. Conclusions:, This MCRT is a simple, inexpensive, well-tolerated and reproducible method with low inter- and intra-observer variability and is well suited for endoscopy units with high workloads. [source] DEWEYAN DARWINISM FOR THE TWENTY-FIRST CENTURY: TOWARD AN EDUCATIONAL METHOD FOR CRITICAL DEMOCRATIC ENGAGEMENT IN THE ERA OF THE INSTITUTE OF EDUCATION SCIENCESEDUCATIONAL THEORY, Issue 3 2008Deborah Seltzer-Kelly Early in the twentieth century, John Dewey also advocated for a vision of education guided by science, and more recent scholarship has validated many of his ideas. However, as Deborah Seltzer-Kelly argues in this essay, Dewey's vision of a scientifically based system of education was very different from that envisioned by the IES, and also very different from that implied by the progenitor of contemporary evolutionary thought, Donald Campbell. Seltzer-Kelly proposes a Deweyan Darwinist model of educational method as a genuinely scientific alternative to the scientism that pervades current official efforts to imbue education with science. The implications of this model are profound, highlighting the difference between education as preparation for consent to authoritarian structures and education as preparation for genuinely democratic participation. [source] WHY DOES A METHOD THAT FAILS CONTINUE TO BE USED?EVOLUTION, Issue 4 2009THE ANSWER It has been claimed that hundreds of researchers use nested clade phylogeographic analysis (NCPA) based on what the method promises rather than requiring objective validation of the method. The supposed failure of NCPA is based upon the argument that validating it by using positive controls ignored type I error, and that computer simulations have shown a high type I error. The first argument is factually incorrect: the previously published validation analysis fully accounted for both type I and type II errors. The simulations that indicate a 75% type I error rate have serious flaws and only evaluate outdated versions of NCPA. These outdated type I error rates fall precipitously when the 2003 version of single-locus NCPA is used or when the 2002 multilocus version of NCPA is used. It is shown that the tree-wise type I errors in single-locus NCPA can be corrected to the desired nominal level by a simple statistical procedure, and that multilocus NCPA reconstructs a simulated scenario used to discredit NCPA with 100% accuracy. Hence, NCPA is a not a failed method at all, but rather has been validated both by actual data and by simulated data in a manner that satisfies the published criteria given by its critics. The critics have come to different conclusions because they have focused on the pre-2002 versions of NCPA and have failed to take into account the extensive developments in NCPA since 2002. Hence, researchers can choose to use NCPA based upon objective critical validation that shows that NCPA delivers what it promises. [source] WHY DOES A METHOD THAT FAILS CONTINUE TO BE USED?EVOLUTION, Issue 11 2008L. Lacey Knowles As a critical framework for addressing a diversity of evolutionary and ecological questions, any method that provides accurate and detailed phylogeographic inference would be embraced. What is difficult to understand is the continued use of a method that not only fails, but also has never been shown to work,nested clade analysis is applied widely even though the conditions under which the method will provide reliable results have not yet been demonstrated. This contradiction between performance and popularity is even more perplexing given the recent methodological and computational advances for making historical inferences, which include estimating population genetic parameters and testing different biogeographic scenarios. Here I briefly review the history of criticisms and rebuttals that focus specifically on the high rate of incorrect phylogeographic inference of nested-clade analysis, with the goal of understanding what drives its unfettered popularity. In this case, the appeal of what nested-clade analysis claims to do,not what the method actually achieves,appears to explain its paradoxical status as a favorite method that fails. What a method promises, as opposed to how it performs, must be considered separately when evaluating whether the method represents a valuable tool for historical inference. [source] A COMPARATIVE METHOD FOR STUDYING ADAPTATION TO A RANDOMLY EVOLVING ENVIRONMENTEVOLUTION, Issue 8 2008Thomas F. Hansen Most phylogenetic comparative methods used for testing adaptive hypotheses make evolutionary assumptions that are not compatible with evolution toward an optimal state. As a consequence they do not correct for maladaptation. The "evolutionary regression" that is returned is more shallow than the optimal relationship between the trait and environment. We show how both evolutionary and optimal regressions, as well as phylogenetic inertia, can be estimated jointly by a comparative method built around an Ornstein,Uhlenbeck model of adaptive evolution. The method considers a single trait adapting to an optimum that is influenced by one or more continuous, randomly changing predictor variables. [source] ADAPTIVE CONSTRAINTS AND THE PHYLOGENETIC COMPARATIVE METHOD: A COMPUTER SIMULATION TESTEVOLUTION, Issue 1 2002Emilia P. Martins Abstract Recently, the utility of modern phylogenetic comparative methods (PCMs) has been questioned because of the seemingly restrictive assumptions required by these methods. Although most comparative analyses involve traits thought to be undergoing natural or sexual selection, most PCMs require an assumption that the traits be evolving by less directed random processes, such as Brownian motion (BM). In this study, we use computer simulation to generate data under more realistic evolutionary scenarios and consider the statistical abilities of a variety of PCMs to estimate correlation coefficients from these data. We found that correlations estimated without taking phylogeny into account were often quite poor and never substantially better than those produced by the other tested methods. In contrast, most PCMs performed quite well even when their assumptions were violated. Felsenstein's independent contrasts (FIC) method gave the best performance in many cases, even when weak constraints had been acting throughout phenotypic evolution. When strong constraints acted in opposition to variance-generating (i.e., BM) forces, however, FIC correlation coefficients were biased in the direction of those BM forces. In most cases, all other PCMs tested (phylogenetic generalized least squares, phylogenetic mixed model, spatial autoregression, and phylogenetic eigenvector regression) yielded good statistical performance, regardless of the details of the evolutionary model used to generate the data. Actual parameter estimates given by different PCMs for each dataset, however, were occasionally very different from one another, suggesting that the choice among them should depend on the types of traits and evolutionary processes being considered. [source] A NEW TEST APPARATUS AND METHOD FOR FRICTION FORCE MEASUREMENT IN JOURNAL BEARINGS UNDER DYNAMIC LOADING: Part IEXPERIMENTAL TECHNIQUES, Issue 5 2005A. Biyiklio No abstract is available for this article. [source] RESIDUAL STRESS MEASUREMENT USING THE HOLE DRILLING METHOD AND LASER SPECKLE INTERFEROMETRYEXPERIMENTAL TECHNIQUES, Issue 4 2003E. Ponslet First page of article [source] APPLICATION OF THE DIRECT COMPLEX STIFFNESS METHOD TO ENGINE MOUNTSEXPERIMENTAL TECHNIQUES, Issue 3 2000S. Nadeau No abstract is available for this article. [source] ON THE GEOCHRONOLOGICAL METHOD VERSUS FLOW SIMULATION SOFTWARE APPLICATION FOR LAHAR RISK MAPPING: A CASE STUDY OF POPOCATÉPETL VOLCANO, MEXICOGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2010ESPERANZA MUŃOZ-SALINAS ABSTRACT. Lahars are hazardous events that can cause serious damage to people who live close to volcanic areas; several were registered at different times in the last century, such as at Mt St Helens (USA) in 1980, Nevado del Ruiz (Colombia) in 1985 and Mt Pinatubo (Philippines) in 1990. Risk maps are currently used by decision-makers to help them plan to mitigate the hazard-risk of lahars. Risk maps are acquired based on a series of tenets that take into account the distribution and chronology of past lahar deposits, and basically two approaches have been used: (1) The use of Flow Simulation Software (FSS), which simulates flows along channels in a Digital Elevation Model and (2) The Geochronological Method (GM), in which the mapping is based on the evaluation of lahar magnitude and frequency. This study addresses the production of a lahar risk map using the two approaches (FSS and GM) for a study area located at Popocatépetl volcano , Central Mexico. Santiago Xalitzintla, a town located on the northern flank of Popocatépetl volcano, where volcanic activity in recent centuries has triggered numerous lahars that have endangered local inhabitants, has been used for the case study. Results from FSS did not provide satisfactory findings because they were not consistent with lahar sediment observations made during fieldwork. By contrast, the GM produced results consistent with these observations, and therefore we use them to assess the hazard and produce the risk map for the study area. [source] Relationships of Sexual Abuse, Connectedness, and Loneliness to Perceived Well-Being in Homeless YouthJOURNAL FOR SPECIALISTS IN PEDIATRIC NURSING, Issue 2 2002Lynn RewArticle first published online: 23 FEB 200 ISSUES AND PURPOSE. To describe respondents' perceptions of connectedness, loneliness, and well-being; and to explore relationships among these variables. DESIGN AND METHOD. Survey data from 96 participants, focus group interviews with 32 participants, and 10 individual interviews were analyzed. RESULTS. Sixty percent of the sample reported sexual abuse, which was significantly related to loneliness and inversely related to connectedness and perceived well-being. Subjects felt lonely and disconnected. They perceived their well-being in terms of current health status. PRACTICE IMPLICATIONS. High rates of sexual abuse, lack of connectedness, and loneliness may help to explain poor perceived well-being in homeless youth. [source] A Longitudinal Study to Determine the Effects of Mentoring on Middle School Youngsters by Nursing and Other College StudentsJOURNAL OF CHILD AND ADOLESCENT PSYCHIATRIC NURSING, Issue 4 2007APRN-BC, Sylvia M. A. Whiting PhD PURPOSE:, This study aims to utilize nursing and other college students in conducting a mentoring project aimed at determining outcomes of behavior and attitude of high-risk middle school students over a 5-year period. METHOD:, A quasi-experimental study with a sample of fifth and sixth graders was conducted in which mentored subjects were tested using multiple instruments and school data to identify behavioral and attitudinal outcomes. Statistical analyses were conducted using chi-square and one-way analysis of variance. FINDINGS:, Academically below-average males in the treatment group were the only cohort demonstrating significant change across all measures. The magnitude of change in this cohort, however, did significantly affect treatment group outcomes overall. Females in both treatment and control groups reflected similar changes. CONCLUSIONS:, Mentoring of schoolchildren is difficult to accomplish using college mentors because of time and schedule commitments. When college mentors are used, grade allocation seems to be a stronger incentive than when payment is the sole reward. Males whose grades are below average demonstrated positive outcomes from the mentoring experience. [source] The Relationship between Behavioral Inhibition and Time Perception in ChildrenJOURNAL OF CHILD AND ADOLESCENT PSYCHIATRIC NURSING, Issue 4 2005Julie B. Meaux PhD PURPOSE:,To test one component of Barkley's (1997) model of executive functions by examining the relationship between behavioral inhibition and time perception in children. METHOD:,Correlation analysis was used to determine the relationships between measures of behavioral inhibition and time perception for the entire sample, and for boys (n = 34) and girls (n = 26) separately. FINDINGS:,For both parent and child measures, behavioral inhibition and time perception scores were correlated for the total group and for girls. Child measure of behavioral inhibition and time perception were not correlated for boys. CONCLUSIONS:,The findings of this study support Barkley's theory and indicate a relationship between poor behavioral inhibition and poor time perception in children. [source] EFFECT OF SLAUGHTER METHOD ON DEGRADATION OF INTRAMUSCULAR TYPE V COLLAGEN DURING SHORT-TERM CHILLED STORAGE OF CHUB MACKEREL SCOMBER JAPONICUSJOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2002KENJI SATO ABSTRACT The present paper demonstrates that a nonstntggling slaughter method can delay degradation of type V collagen in meat of chub mackerel Scomber japonicus and softening of the meat during postharvest chilled storage. The fish were slaughtered by piercing a knife into nape (nonstruggling method) or by leaving on ground (struggling method) and then stored in an ice box. Sensory study revealed that the postharvest softening of the meat was moderated at 4 and 8 h by the non-struggling slaughter method in comparison with the struggling method. On the basis of the specific solubilization of type V collagen and reduced tyrosine content in it, a cleavage of the nonhelical regions (telopeptides) of the type V collagen occurred during the chilled storage in the fish slaughtered by the struggling method. The degradation of type V collagen was also slower in the meat of the fish slaughtered by the nonstruggling method, which can be directly linked to the moderation of the postharvest softening. [source] A NEW METHOD FOR ELLAGIC ACID PRODUCTION FROM POMEGRANATE HUSKJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2008JINGJING LU ABSTRACT Pomegranate (Punica granatum L.) husk, a by-product of the pomegranate juice industry, is an inexpensive and abundant source of ellagic acid. Ellagic acid is widely used as functional food for its physiological functions. It is the breakdown product of ellagitannins. To date, the preparation of ellagic acid from pomegranate husk has not been reported. This article reports a new process for ellagic acid production from pomegranate husk by extraction of tannins followed by acid hydrolysis and purification by extraction and recrystallization. Several tests were conducted to obtain optimum conditions including extraction of tannins by varying solvents, acid concentration and reaction time for acid hydrolysis and the volume of methanol used for purification. Ellagic acid (3.5 g) with 90% purity from 100 g pomegranate husk was obtained. This new method is easy to scale up. All equipment used in this production process is widely used in food processing industry. The cost of production is low. It is suitable for industrial applications. PRACTICAL APPLICATIONS The production of ellagic acid is easier and the yield and purity of ellagic acid produced this way are higher than before. This method can be used not only for experiment in laboratory but also for industrial applications. The material , pomegranate husk , is a by-product of the pomegranate juice industry, so it is very cheap and easy to get. High-purity ellagic acid produced this way is sold to many companies back home and abroad. It is used as food additive and cosmetic material because of its antioxidant activity and whiteningfunction. The toxicity of pomegranate husk is lower than that of gallnut, which has been the main material of ellagic acid production in the past. Reagents are common and inexpensive; some of them are reusable. [source] A SIMPLE METHOD TO DETERMINE DIFFUSION OF SODIUM IN THE EPIDERMIS OF GREEN OLIVESJOURNAL OF FOOD PROCESS ENGINEERING, Issue 5 2004CARLOS ALBERTO ZURITZ ABSTRACT The present study reports a simple method, both mathematical and experimental, to determine variable effective diffusion coefficients for sodium through the skins of olives. Skins removed from green olives, variety Arauco (also known as Criolla), were studied using a lye concentration of 2.25% (w/w) of NaOH at 20C. The diffusion of sodium was evaluated through fresh skins and previously alkali-treated skins. The measured values of effective diffusion coefficients for untreated (fresh) olive skins increased two orders of magnitude during the processing time, from 10,12 to 10,10 m2/s. Whereas, the effective diffusion coefficients determined for previously treated olive skins were of the order of 10,10 m2/s and increased very little with treatment time. [source] COMPLEX METHOD FOR NONLINEAR CONSTRAINED MULTI-CRITERIA (MULTI-OBJECTIVE FUNCTION) OPTIMIZATION of THERMAL PROCESSINGJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2003FERRUH ERDO ABSTRACT The goal in a multi-objective function optimization problem is to optimize the several objective functions simultaneously. the complex method is a powerful algorithm to find the optimum of a general nonlinear function within a constrained region. the objective of this study was to apply the complex method to two different shapes (a sphere and a finite cylinder) subjected to the same thermal processing boundary conditions to find a variable process temperature profile (decision variable) to maximize the volume-average retention of thiamine. A process temperature range of 5 to 150C was used as an explicit constraint. Implicit constraints were center temperature and accumulated center lethality of the sphere and the finite cylinder. the objective functions for both shapes were combined into a single one using a weighting method. Then, the previously developed complex algorithm was applied using Lexicographic Ordering to order the objective functions with respect to their significance. the results were reported as optimum variable process temperature profiles using the given geometries and objective functions. the thiamine retentions were also compared with a constant process temperature process, and 3.0% increase was obtained in the combined objective function. the results showed that the complex method can be successfully used to predict the optimum variable process temperature profiles in multi-criteria thermal processing problems. [source] MICROBIAL, CHEMICAL AND PHYSICAL CHANGES IN CHILL WATER TREATED WITH ELECTROCHEMICAL METHODJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2000LI MA ABSTRACT A three-zone (anode, neutral, and cathode) electrochemical treatment chamber was designed and built to evaluate the inactivation of Salmonella typhimurium in poultry chill water. The chill water in the three-zone chamber containing ,106 CFU/mL S. typhimurium and 0.5% or 1.0% NaCl was treated at 15 or 25 mA/cm2, and a temperature of 5,10C for up to 10 min. The Salmonella were inactivated within 0.5 to 4 min in the anode zone depending on the salt concentration and current density, slower inactivation rate in the cathode zone, and almost no inactivation in the neutral zone. The pH decreased to , 2 in anode zone, but increased to , 10 in the cathode zone. Temperature increased by 2,6.5C in the three zones depending on current density and salt concentration. The conductivity increased in the anode and cathode zones but little change in the neutral zone. The generated chlorine was proportional to the current density and the treatment time. [source] APPLICATION OF EXPERIMENTAL DESIGN METHOD TO THE OIL EXTRACTION FROM OLIVE CAKEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2009SMAIL MEZIANE ABSTRACT Olive cake is an important solid waste of the olive oil production. It still contains a certain quantity of oil that can be recovered by means of solvent extraction. In this study, two-level full factorial design was performed to evaluate the effects of four variables and their interactions on the oil extraction by the ethanol 96.0% in a batch reactor. The variables included size of particles, temperature, and time of contact and solvent-to-solids ratio. The statistical analysis of the experimental data showed that the extracted oil mass depends on all the examined variables. It also depends on the interactions between size of particles and solvent-to-solid ratio and size of particles and temperature. The experimental data were in good agreement with those predicted by the model. PRACTICAL APPLICATIONS Olive cake is solid waste of the olive oil industry that is available in large amounts in many Mediterranean countries and at very low cost. It can be treated or valorized, enabling at the same time the solution to environmental problems caused by the olive oil production process. The economic interest that it presents is especially because of the residual oil that it contains and that can be recovered by solvent extraction. However, this solid,liquid extraction depends on several parameters: the ones inherent to the products (structure and properties of the sample, nature of extraction solvent); and the others to the extraction process (time of contact, temperature of extraction, solvent-to-solid ratio, stirring velocity). The experimental design method enables to determine the most important variables and their interaction in the extraction process at the same time performing a low number of experiments. [source] PROPOSED NEW COLOR RETENTION METHOD FOR TILAPIA FILLETS (O. NILOTICUS, × O. AUREUS,) BY EUTHANATIZING WITH REDUCED CARBON MONOXIDEJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2008LAIHAO LI ABSTRACT The conditions of color retention for tilapia fillets (O. niloticus, × O. aureus,) treated by euthanatizing with reduced carbon monoxide (CO) were investigated. Live tilapias were first exposed to water saturated with CO. After a certain amount of CO-saturated water had been pumped through the gills, the tilapias were timely picked out and killed following the industry guidelines. The color value of fillets was measured by colorimeter to evaluate the color retention. The results showed that (1) temperature did not have a significant effect on the color of the fillets; (2) the optimal conditions were a ratio of 3:1, v/w between water and fish, a CO flow rate of 80 mL/min and 10 min CO injection followed by 5 min air exposure. Under these conditions, a higher a*value (redness 19.44) and a better sensory evaluation value (4.8) were obtained; and (3) the proposed method shortened processing time by 30,35 min, reduced the frequency of sterilization to only once, significantly lowered microbial counts from 82.33 × 102 to 56.33 × 102 and reduced the CO requirement 25-fold, which has significant occupation, health, safety, and environmental implications. PRACTICAL APPLICATIONS Color retention for tilapias is conventionally accomplished by treating fillets with CO. Recently, euthanatizing tilapias with CO has been assumed to be an effective way to shorten processing time and to lessen product handling process. Many factories have been searching for a way to solve the problem of color retention for tilapias or other red muscle treatment, but there has been a lack of information on how euthanasia affects fish quality, especially red muscle color. The objective of this experiment was to explore the application of the new method. [source] EFFECTS of SHUCKING METHOD ON OPENING, MEAT YIELD and SELECTED QUALITY PARAMETERS of WEST AFRICAN CLAM, GALATEA PARADOXA (BORN)JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 5 2000E.O. EKANEM Samples (n= 100) of freshly harvested clams (Galatea paradoxa Born) from the Cross River, Nigeria, were subjected after 24 h depurations to heat treatment (steam and water at 60, 70, 80, 90, 100C) for 1,6 min to evaluate the effects of level of heat treatment on opening, meat yield, sensory properties, proximate composition, pH and electrical conductivity (EC). Observations were also made on the effects of some chemical shucking aids (NaOH, NaHCO3, Na2CO3, NaCl) in 60C water on these parameters. Results showed that boiling water was most effective in opening the clams, with 100% shucking achieved in 1 min. Steam was least effective, requiring 6 min for 100% opening. Temperature significantly and strongly influenced meat yield (p<0.05;r=-0.92). pH (p<0.01; r=0.97), EC (p<0.05; r =0.65) and sensory properties (p<0.05). In general, shucking aids reduced opening time, significantly p<0.05) raised meat pH and EC, and with the exception of NaCl, insignificantly (P>0.05) improved yield. NaHCO3, and Na2CO3, which cut time for 100% opening from 5 min to 2 min were most effective. There were slight but significant (P <0.05) drops in meat moisture, crude protein and ash contents with increase in temperature (T). the model equations, pH = 4.69 + 0.021 T and % yield = 39.95,0.172 T were found to reliably predict meat pH and yield, with insignificant differences (P>0.05) between predicted and experimental values. [source] EFFECT OF METHOD OF PRESERVATION OF PULP ON THE QUALITY OF CARBONATED AND NONCARBONATED BEVERAGES PREPARED FROM PEACH FRUITJOURNAL OF FOOD QUALITY, Issue 6 2009SHEETU ARORA ABSTRACT Peach pulp preserved by different methods, i.e., processing at 100C for 30 min, potassium metabisulphite (KMS; 2,000 ppm), sodium benzoate (750 ppm) and mixture of KMS and sodium benzoate (1,000 and 375 ppm) had no significant effect on total soluble solids (TSS), acidity, TSS : acid ratio, pH of carbonated as well as noncarbonated beverages. Carbonated beverages prepared from pulp with 750 ppm of sodium benzoate retained significantly (P , 0.05) higher carbon dioxide (CO2) content and CO2 gas : volume during storage. Color of the beverages prepared from peach pulp containing KMS was better but the beverages prepared from peach pulp preserved by processing and addition of sodium benzoate were organoleptically more acceptable. Both carbonated and noncarbonated drinks remained organoleptically acceptable throughout storage. Suspension of carbonated beverages was significantly (P , 0.05) higher during storage as compared with noncarbonated beverages. PRACTICAL APPLICATIONS Peaches are valued as a table fruit for a short period of time from end of April to end of May. The acceptability and utilization of this fruit can be increased by processing it into delicious carbonated and noncarbonated beverages. This will provide nutritious drink to the consumers and also help in increasing the fruit cultivation resulting in good returns to the growers. This study will also help to give a fillip to the establishment of a peach beverage industry world wide. [source] | ||||||||||||||||||||||||||||||||||||||||