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Greatest Effect (greatest + effect)
Selected AbstractsMicrostructure and mechanical properties related to particle size distribution and composition in dark chocolateINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 1 2009Emmanuel Ohene Afoakwa Summary Composition in dark chocolate was varied and the effects determined on microstructure, using light microscopy, and mechanical properties of molten and tempered chocolates, using a TA.HD Plus Texture Analyser. Compositional parameters were particle size distribution (PSD) (D90 of 18, 25, 35 and 50 ,m), fat (25%, 30% and 35%) and lecithin (0.3% and 0.5%) contents. Micrographs revealed wide variations in sugar crystalline network structure and inter-particle interaction strengths related to PSD and fat level. Samples containing 25% fat had more crystal agglomerates, well flocculated with greater particle-to-particle interaction strengths than those with higher (30% and 35%) fat contents. Increasing the D90 to 35,50 ,m caused broadening of the PSD, with particles becoming coarser, which were similar at all fat levels. Mechanical analysis showed that PSD, fat and lecithin content significantly influenced firmness of molten chocolate and hardness of solid (tempered) chocolate with significant interactions among factors. Particle size was inversely correlated with firmness (1235,173 g) and hardness (7062,5546 g). Greatest effect of PSD was with 25% fat and 0.3% lecithin. With higher fat and lecithin contents, the PSD influence was reduced. It was concluded that PSD, fat and lecithin contents and their interactions were central to mechanical properties of dark chocolates. [source] Incorporating Uncertainty into Demographic Modeling: Application to Shark Populations and Their ConservationCONSERVATION BIOLOGY, Issue 4 2002Enric Cortés I used age-structured life tables and Leslie matrices based on a prebreeding survey and a yearly time step applied only to females to model the demography of 41 populations from 38 species of sharks representing four orders and nine families. I used Monte Carlo simulation to reflect uncertainty in the estimates of demographic traits and to calculate population statistics and elasticities for these populations; I used correlation analysis to identify the demographic traits that explained most of the variation in population growth rates ( , ). The populations I examined fell along a continuum of life-history characteristics that can be linked to elasticity patterns. Sharks characterized by early age at maturity, short lifespan, and large litter size had high , values and short generation times, whereas sharks that mature late and have long lifespans and small litters have low , values and long generation times. Sharks at the "fast" end of the spectrum tended to have comparable adult and juvenile survival elasticities, whereas sharks at the "slow" end of the continuum had high juvenile survival elasticity and low age,zero survival ( or fertility ) elasticity. Ratios of adult survival to fertility elasticities and juvenile survival to fertility elasticities suggest that many of the populations studied do not possess the biological attributes necessary to restore , to its original level after moderate levels of exploitation. Elasticity analysis suggests that changes in juvenile survival would have the greatest effect on ,, and correlation analysis indicates that variation in juvenile survival, age at maturity, and reproduction account for most of the variation in ,. In general, combined results from elasticity and correlation analyses suggest that research, conservation, and management efforts should focus on these demographic traits. Resumen: Exploré los efectos de la incertidumbre en los caracteres demográficos en análisis demográficos de tiburones, un método no empleado con anterioridad para este taxón. Utilicé tablas de vida estructuradas por edades y matrices de Leslie basadas en evaluaciones pre-gestación y pasos de tiempo de un año aplicados solo a las hembras para modelar la demografía de 41 poblaciones de 38 especies de tiburones que representan cuatro órdenes y nueve familias. Utilicé la simulación de Monte Carlo para reflejar la incertidumbre en las estimaciones de caracteres demográficos y calcular las estadísticas y elasticidades poblacionales para estas poblaciones y el análisis de correlación para identificar los caracteres demográficos que explican la mayoría de la variación en las tasas de crecimiento poblacional ( , ). Las poblaciones examinadas caen dentro de un continuo de características de historias de vida que pueden estar vinculadas con los patrones de elasticidad. Los tiburones que maduran a temprana edad y tienen corta duración de vida y grupos grandes de crías tuvieron valores altos de , y tiempos generacionales cortos, mientras que los tiburones que maduran tarde y tienen una duración de vida larga y grupos pequeños de crías tienen valores bajos de , y tiempos generacionales largos. Los tiburones que se encuentran en el punto final "rápido" del espectro tendieron a tener elasticidades de supervivencia de adultos y juveniles comparables, mientras que los tiburones en el punto final "lento" del continuo tuvieron una alta elasticidad de supervivencia de juveniles y una baja elasticidad en supervivencia a la edad cero (o fertilidad ). Las proporciones de elasticidades de supervivencia de adultos y fertilidad y de elasticidades de supervivencia de juveniles y fertilidad sugieren que muchas de las poblaciones estudiadas no poseen los atributos biológicos necesarios para restaurar , a su nivel original después de niveles moderados de explotación. El análisis de elasticidad sugiere que en la supervivencia de juveniles se podría tener el efecto mayor de , y el análisis de correlación indica que la variación en la supervivencia de juveniles, la edad de maduración y reproducción explican la mayor parte de la variación en ,. En general, los resultados combinados de los análisis de elasticidad y correlación sugieren que los esfuerzos de investigación, conservación y manejo deberían enfocarse a estas características demográficas. [source] Contextual modulation of spatial discrimination reversal in developing ratsDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2005Jerome H. Pagani Abstract Reversal of discrimination learning is influenced by manipulation of the training context. In adult and developing rats, contextual changes made between acquisition and reversal aid the learning of the new discrimination, possibly by serving to release proactive interference from the originally acquired discrimination (M. E. Bouton & D. C. Brooks, 1993; N. Spear, G. Smith, R. Bryan, & W. Gordon, 1980). The present study sought to examine this effect in an appetitive T-maze task, as a function of different contextual manipulations. Rats of three ages, Postnatal Day (PND) 19, PND23, and PND30, were tested for their ability to acquire and reverse a position habit in a T-maze. Contextual changes were made between acquisition and reversal sessions and consisted of one of three manipulations: (a) texture; the texture of the maze floor was changed via the addition or subtraction of wire mesh; (b) maze; subjects were reversed in a different maze that was identical in construction to the training maze, but differed in spatial location; (c) texture and maze; subjects were shifted to the new maze, the floor of which differed in texture from the training maze but was otherwise identical in construction. Results showed that the texture,maze combination was an effective aid to reversal learning at all ages tested. The texture alone, however, was not effective at any age. The maze alone also was an effective cue for reversal, but proved to have the greatest effect for PND30 subjects. During ontogeny, the contextual modulation of reversal learning is importantly influenced by the nature and the salience of the contextual cue. © 2004 Wiley Periodicals, Inc. Dev Psychobiol 46: 36,46, 2005. [source] In Search of Better Quality of EU Regulations for Prompt Transposition: The Brussels PerspectiveEUROPEAN LAW JOURNAL, Issue 5 2008Michael Kaeding The quality of EU regulation is crucial to ensuring that Community law is promptly transposed into national law within the prescribed deadlines. But good quality transposition (clear, simple, and effective) goes beyond pre-legislative consultation processes and more frequent use of impact assessments as agreed in the 2003 Interinstitutional Agreement on Better Lawmaking. Presenting new data that covers the full population of all EU transport directives from 1995 to 2004,including the national implementing instruments of France, Germany, Greece, Italy, Ireland, Spain, Sweden, the Netherlands and the UK,this study shows that elements of the EU directives delay transposition. The binding time limit for transposition, the EU directive's level of discretion, its level of detail, its nature and further characteristics of the directive's policy-making process are all factors. These determining factors are crucial to explaining why Member States miss deadlines when transposing EU Internal Market directives. Brussels' efforts to simplify and improve the regulatory environment have to go beyond more preventive action to strengthen the enforcement of EU legislation at the member-state level if they want to address the Internal Market constraining effects of Member States' non-compliance. This study argues that far-reaching decisions made in the European Commission's drafting and EU policy-making phase have the greatest effect on the European regulatory framework in which businesses operate and the free movement of goods, persons, services, and capital is at stake. Implementation should be part of the design. [source] Perceptions of Effectiveness of Responses to Sexual Harassment in the US Military, 1988 and 1995GENDER, WORK & ORGANISATION, Issue 1 2003Juanita M. Firestone This analysis compares patterns of response to the harassment experiences that had the greatest effect on the respondents to the ,1988 Department of Defense (DoD) Survey of Sex Roles in the Active-Duty Military' and Form A of the ,1995 Armed Forces Sexual Harassment Survey'. We analyse the respondents' perceptions about effectiveness of their responses, and respondents' opinions about the efforts of senior military leadership, and their own immediate supervisors' efforts to ,make honest and reasonable efforts to stop sexual harassment in the active-duty military' (DoD, 1988; Bastian et al., 1996). Results indicate that while the military has been somewhat successful in attempts to lower actual incidence of sexual harassment, the percentage of those experiencing such uninvited and unwanted behaviours remains high. Similar patterns of responses in both years, with most employing personal solutions and few filing complaints with officials, may reflect the fact that official DoD policy focuses on individual behaviour and does not address the masculine environmental context that promotes such behaviours (see also Harrell and Miller, 1997). Findings also suggest that the ,no tolerance' policies adopted by the military may concentrate on the military image but ignore the wishes of the complainants who fear reprisals. If the rights and wishes of all parties involved are not taken into account, policies are unlikely to be successful (see, for example, Rowe, 1996). [source] Density effects on life-history traits in a wild population of the great tit Parus major: analyses of long-term data with GIS techniquesJOURNAL OF ANIMAL ECOLOGY, Issue 2 2006TEDDY A. WILKIN Summary 1Population density often has strong effects on the population dynamics and reproductive processes of territorial animals. However, most estimates of density-dependent effects use the number of breeding pairs per unit area in a given season and look for correlations across seasons, a technique that assigns the same density score to each breeding pair, irrespective of local spatial variation. 2In this study, we employed GIS techniques to estimate individual breeding densities for great tits breeding in Wytham Woods UK, between 1965 and 1996. We then used linear mixed modelling to analyse the effect of density on reproductive processes. 3The areas of Thiessen polygons formed around occupied nestboxes were used to approximate territory size (necessarily inverse of breeding density). There were significant, independent and positive relationships between clutch size, fledging mass and the number of offspring recruited to the population, and territory size (all P < 0·001), but no effect of territory size on lay-date or egg mass. 4Thiessen polygons are contiguous and cover all of the available area. Therefore, at low nest densities territory polygons were excessively oversized. Using a novel procedure to address this limitation, territory sizes were systematically capped through a range of maxima, with the greatest effect in the models when territories were capped at 0·9,2·3 ha. This figure approximates to the maximum effective territory size in our population and is in close agreement with several field-based studies. This capping refinement also revealed a significant negative relationship between lay-date and territory size capped at 0·9 ha (P < 0·001). 5These density-dependent effects were also detected when analyses were restricted to changes within individual females, suggesting that density effects do not merely result from either increased proportions of low-quality individuals, or increased occupation of poor sites, when population density is high. 6Overall, these results suggest that, in the current population, great tits with territories smaller than c. 2 ha independently lay smaller and later clutches, have lighter fledglings, and recruit fewer offspring to the breeding population. These analyses thus suggest a pervasive and causal role of local population density in explaining individual reproductive processes. [source] A model of bovine tuberculosis in the badger Melesmeles: an evaluation of control strategiesJOURNAL OF APPLIED ECOLOGY, Issue 3 2001G.C. Smith Summary 1,An individual-based stochastic simulation model was used to investigate the control of bovine tuberculosis (TB) in the European badger Meles meles. Nearly all population and epidemiological parameters were derived from one study site, and the transmission of TB from badgers to cattle was included. The latter is an essential step if reactive badger control strategies are to be modelled. 2,The model appeared to underestimate slightly the rate of population recovery following widespread culling. This may have been due to simulating an isolated population with no immigration and no compensatory increase in fecundity. This should not affect the relative efficacy of each control strategy, but does require further investigation. 3,Of the historical methods of badger control, gassing and the ,clean ring' strategies were the most effective at reducing disease prevalence in the badger and cattle herd breakdown rates. These results agree with those of earlier models. 4,The proactive badger removal operation as part of the current field trial should cause a dramatic decrease in the number of cattle herd breakdowns, but also has the greatest effect on the badger population size. 5,The proactive use of a live test to detect TB, followed by vaccination, appears to reduce substantially cattle herd breakdowns and disease prevalence in the badger. 6,Three combined control strategies gave the best initial reduction in cattle herd breakdown rate and disease prevalence in the badger: (i) a proactive cull followed by reactive test and cull; (ii) a continued vaccination and proactive test and cull; and (iii) a continuous proactive test and cull. 7,The results of simulation models suggest that badger vaccination is a very good method of TB control. This is at odds with simple models and requires further investigation. [source] A comparison of regeneration dynamics following gap creation at two geographically contrasting heathland sitesJOURNAL OF APPLIED ECOLOGY, Issue 5 2000A.J. Britton 1.,Lowland Calluna -dominated heathlands are a high priority for conservation in Europe. As an anthropogenic subclimax community they require regular management intervention to maintain their conservation interest. 2.,Increasingly, Calluna is disappearing from lowland heathlands and being replaced by grasses, especially in the Netherlands and more recently in south-east England. While Calluna is highly competitive over much of its life cycle, its competitive ability is reduced during the regeneration phase that follows the death of stands or results from management activity. 3.,We examined the influence of five factors on regeneration of vegetation in gaps in two broadly similar lowland dry heaths over a 3-year period. These were: geographical location (combining a variety of environmental contrasts); dominant species (Calluna or grasses); management techniques; gap size; and seed source availability. 4.,Site location had the greatest effect on patterns of regeneration. Regeneration on the Wirral (north-west England) was faster and more dominated by Calluna than regeneration in Breckland (south-east England), which was dominated by other species including grasses and annual plants. Addition of Calluna seed at the Breckland site failed to increase Calluna cover. It was concluded that climatic or other environmental factors were the most probable cause of poor regeneration. 5.,Cover of grasses in regenerating areas was greatest in Breckland, where Deschampsia was able to establish in all gaps where there was a seed source (either in the surrounding vegetation or applied as a treatment). On the Wirral, Deschampsia establishment was limited, even in gaps where a seed source was applied. 6.,This work has implications for the conservation management of heathlands, which currently follows a standard prescription throughout the UK. It is suggested that management regimes should be tailored to suit the conditions prevailing at individual sites as regeneration dynamics may be extremely variable. [source] Optimization of growth medium for the production of ,-amylase from Bacillus amyloliquefaciens using response surface methodologyJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 4 2006M Saban Tanyildizi Abstract The optimization of nutrient levels for the production of ,-amylase by Bacillus amyloliquefaciens was carried out using response surface methodology (RSM) based on the 23 factorial central composite design (CCD). This procedure limited the number of actual experiments performed while allowing for possible interactions between three components. RSM was adopted to derive a statistical model for the effect of starch, peptone and yeast extract (YE) on ,-amylase production. The P -value of the coefficient for linear effects of starch and YE concentration was <0.0001, suggesting that this was the principal experimental variable, having the greatest effect on the production of ,-amylase. The optimal combinations of media constituents for maximum ,-amylase production were determined as 12.61 g L,1 starch, 2.83 g L,1 peptone and 1.25 g L,1 YE. The optimization of the medium resulted not only in a 34% higher enzyme activity than unoptimized medium but also in a reduced amount of the required medium constituents. Copyright © 2006 Society of Chemical Industry [source] Fatigue in multiple sclerosis patientsJOURNAL OF CLINICAL NURSING, Issue 9 2009Mukadder Mollao Aim., This study aimed to describe fatigue and the factors that affect fatigue in people with multiple sclerosis. Background., Fatigue is the most common symptom and has the greatest effect on multiple sclerosis patients' activities of daily living. There is limited understanding of the level of fatigue experienced by people with multiple sclerosis, with research currently limited to other symptoms and problems related to multiple sclerosis. Design., This research was conducted as a descriptive survey. Methods., The study involved 120 people with multiple sclerosis. The data were collected with a Patient Questionnaire and a Visual Analogue Scale for Fatigue (VAS-F). Variance analysis, Mann,Whitney U -test and Kruskal,Wallis test were used in the data analysis. Results., All of the individuals in the sample experienced fatigue. Their fatigue was also affected by factors such as age, gender, education, marital status, number of children, occupation and duration of illness. In addition, the situations with the greatest effect on their fatigue were taking a hot bath/shower, hot/humid weather, stress, infection and other illnesses causing fever, disturbance in sleep pattern, increase in daily activities and exercise. Conclusions., Fatigue is a symptom that has a significant effect on the daily lives of people with multiple sclerosis. Accordingly, it is recommended that factors affecting fatigue in people with multiple sclerosis be evaluated and that education programmes directed at how to control these factors. Relevance to clinical practice., The determination of factors affecting fatigue is important for multiple sclerosis individuals' ability to cope with fatigue and keep it under control. To be able to accomplish this it is necessary for health care personnel, the family and friends to work together. [source] Experimentally manipulated change in children's proactive and reactive aggressive behaviorAGGRESSIVE BEHAVIOR, Issue 3 2003Nancy C. Phillips Abstract The current study assessed the effectiveness of two behavior manipulations created to differentially lower aggressive responses in a laboratory task. It was hypothesized that the reactive anger manipulation would have the greatest effect for reactive aggressive behavior and the instrumental manipulation would significantly affect proactive aggressive behavior and slightly affect the reactive behavior. Fifty participants played pinball in competition for points against an unknown peer, whose responses were actually controlled by the experimenter. Participants could push a noise button, sending the peer an annoying noise; a tilt button, interfering with the opponent's game; or a no answer button, offering a pro-social alternative to aggression. After playing four rounds, participants were randomly assigned to either a reactive anger or a positive instrumental manipulation group; they then played pinball again for four rounds. Results indicate that the instrumental manipulation significantly lowered aggressive responses for both reactive and proactive behavior. The reactive manipulation effected aggressive responses only for use of the noise button and produced significantly lower levels of anger. Aggr. Behav. 29:215,227, 2003. © 2003 Wiley-Liss, Inc. [source] Effects of temperature on larval fish swimming performance: the importance of physics to physiologyJOURNAL OF FISH BIOLOGY, Issue 4 2002I. Hunt von Herbing Temperature influences both the physiology offish larvae and the physics of the flow conditions under which they swim. For small larvae in low Reynolds number (Re) hydrodynamic environments dominated by frictional drag, temperature-induced changes in the physics of water flow have the greatest effect on swimming performance. For larger larvae, in higher Re environments, temperature-induced changes in physiology become more important as larvae swim faster and changes in swimming patterns and mechanics occur. Physiological rates at different temperatures have been quantified using Q10s with the assumption that temperature only affected physiological variables. Consequently, Q10s that did not consider temperature-induced changes in viscosity overestimated the effect of temperature on physiology by 58% and 56% in cold-water herring and cod larvae respectively. In contrast, in warm-water Danube bleak larvae, Q10s overestimated temperature-induced effects on physiology by only 5,7%. This may be because in warm water, temperature-induced changes affect viscosity to a smaller degree than in cold water. Temperature also affects muscle contractility and efficiency and at high swimming velocities, efficiency decreases more rapidly in cold-exposed than in warm-exposed muscle fibres. Further experiments are needed to determine whether temperature acts differently on swimming metabolism in different thermal environments. While hydrodynamic factors appear to be very important to larval fish swimming performance in cold water, they appear to lose importance in warm water where temperature effects on physiology dominate. This may suggest that major differences exist among locomotory capacities of larval fish that inhabit cold, temperate waters compared to those that live in warm tropical waters. It is possible that fish larvae may have developed strategies that affect dispersal and recruitment in different aquatic habitats in order to cope not only with temperature-induced physiological challenges, but physical challenges as well. [source] EFFECTS OF ANTIOXIDANTS ON IRRADIATED BEEF COLORJOURNAL OF FOOD QUALITY, Issue 3 2010LAKSHMANAN RAMAMOORTHI ABSTRACT Fresh beef was dipped into ascorbic acid (AA; 500 ppm), butylated hydroxyanisole (BHA, 150 ppm), butylated hydroxytoluene (BHT, 100 ppm) or propyl gallate (PG; 100 ppm); control samples were dipped in deionized water. Samples were vacuum packaged, then irradiated (0, 1.25 or 2.50 kGy). After irradiation, samples were stored (0, 7 or 14 days) at 4C. Color was assessed instrumentally (L*, a*, b*values, hue angles, chroma) and visually. All antioxidants increased L*value by two units (lighter); however, irradiation dose had no effect. Irradiation increased wet dog and rancid odors of beef; however, it decreased sour odor, a*value, chroma and hue angle, and increased visual green and brown colors, indicating that it reduced redness and color intensity. Antioxidants reduced L*(decreased lightening) and a*values (redness) compared to controls. BHA had the greatest effect on a*value. AA decreased visual green color the most; however, BHA and BHT were also effective. Antioxidants had inconsistent effects on b*value, chroma and hue angle. Storage decreased L*and a*values, and chroma. BHA and PG were most effective at maintaining low thiobarbituric acid-reactive substances when samples were irradiated. PRACTICAL APPLICATIONS Irradiation has the potential to reduce microbial load, increasing both the safety and shelf life of red meat products; however, it has the potential to damage fresh meat color, resulting in unacceptable discoloration. Irradiation can increase off-odors (wet dog, rancid) of beef; however, it can decrease sour odor, instrumental measures of red color, and increase visual green and brown colors. Use of antioxidants including ascorbic acid, butylated hydroxytoluene, butylated hydroxyanisole and propyl gallate can help maintain the color of irradiated beef held in refrigerated storage for up to 2 weeks. [source] Response Surface Model for the Estimation of Escherichia coli O 157:H7 Growth under Different Experimental ConditionsJOURNAL OF FOOD SCIENCE, Issue 1 2005Rose Maria García-Gimeno ABSTRACT: In this study, a Response Surface Model (RSM) of Escherichia coli O157:H7 as affected by pH levels, sodium chloride and nitrite concentrations, temperature, and aerobic/anaerobic conditions is presented. The standard error of prediction (%SEP) obtained was acceptable for the growth rate prediction (33%SEP), although a bit high for lag time (53.01 %SEP). Mathematical validation demonstrated that the RSM predicts growth rate values on the fail-safe side in aerobic conditions and within the acceptable range (bias factor [Bf] = 0.99) with acceptable accuracy (accuracy factor [Af] = 1.15), as well as for lag time (Bf = 1.05; Af = 1.25). Temperature was found to have the greatest effect on the kinetic parameters, followed by NaCl concentration and pH. In the experimental range considered here (0 to 200 ppm), NaNO2 concentration was found to have a significant effect on growth rate but not on lag time. [source] Oral quinolones in hospitalized patients: an evaluation of a computerized decision support intervention,JOURNAL OF INTERNAL MEDICINE, Issue 4 2004T. Hulgan Abstract. Objective., To determine whether a computerized decision support system could increase the proportion of oral quinolone antibiotic orders placed for hospitalized patients. Design., Prospective, interrupted time-series analysis. Setting., University hospital in the south-eastern United States. Subjects., Inpatient quinolone orders placed from 1 February 2001 to 31 January 2003. Intervention., A web-based intervention was deployed as part of an existing order entry system at a university hospital on 5 February 2002. Based on an automated query of active medication and diet orders, some users ordering intravenous quinolones were presented with a suggestion to consider choosing an oral formulation. Main outcome measure., The proportion of inpatient quinolone orders placed for oral formulations before and after deployment of the intervention. Results., There were a total of 15 194 quinolone orders during the study period, of which 8962 (59%) were for oral forms. Orders for oral quinolones increased from 4202 (56%) before the intervention to 4760 (62%) after, without a change in total orders. In the time-series analysis, there was an overall 5.6% increase (95% CI 2.8,8.4%; P < 0.001) in weekly oral quinolone orders due to the intervention, with the greatest effect on nonintensive care medical units. Conclusions., A web-based intervention was able to increase oral quinolone orders in hospitalized patients. This is one of the first studies to demonstrate a significant effect of a computerized intervention on dosing route within an antibiotic class. This model could be applied to other antibiotics or other drug classes with good oral bioavailability. [source] A systematic iterative procedure for determining granulator operating parametersAICHE JOURNAL, Issue 9 2006Ka Y. Fung Abstract A systematic iterative procedure is presented for determining granulator operating parameters to produce granules with desired product attributes. These include mean granule size, size distribution, porosity, strength, and spatial distribution of the constituent components. After selecting the equipment and binder, a preliminary experiment is performed to determine base case results, which usually do not match the desired attributes. The final product is obtained using an iterative procedure with both analyses and experiments. The qualitative analysis identifies the operating parameters that can effect changes to the off-spec attribute. This is followed by a quantitative analysis,based on simple physically based mathematical models in the form of sensitivity analysis,that determines the parameter that has the greatest effect on the relevant attribute. Experiments with the modified formulation and operating conditions are conducted and the entire procedure is repeated until the desired product is obtained. A system with lactose and starch using hydroxypropyl cellulose as binder in an agitated fluidized bed granulator (Hosokawa Micron AgglomasterÔ) is used to illustrate this procedure. © 2006 American Institute of Chemical Engineers AIChE J, 2006 [source] New insight into the mechanism of hip prosthesis loosening: Effect of titanium debris size on osteoblast functionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 2 2004Daniel T. O'Connor Abstract The incidence of rheumatoid arthritis and osteoarthritis is on the rise due to our expanding elderly population. Total joint arthroplasty is the most successful, prevalent treatment modality for these and other degenerative hip conditions. Despite the wide array of prosthetic devices commercially available, hip prostheses share a common problem with a gradual and then accelerating loss of bone tissue and bone,implant interface integrity, followed by implant instability and loosening. Implant failure is largely the result of inevitable wear of the device and generation of wear debris. To provide information for the development of improved prosthetic wear characteristics, we examined the effects of size-separated titanium particles on bone forming cell populations. We demonstrate unequivocally that particle size is a critical factor in the function, proliferation, and viability of bone-forming osteoblasts in vitro. In addition, we have elucidated the time-dependent distribution of the phagocytosed particles within the osteoblast, indicating an accumulation of particles in the perinuclear area of the affected cells. The report finds that particle size is a critical factor in changes in the bone formation-related functions of osteoblasts exposed to simulate wear debris, and that 1.5,4 ,m titanium particles have the greatest effect on osteoblast proliferation and viability in vitro. The size of titanium particles generated through wear of a prosthetic device may be an important consideration in the development of superior implant technology. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Locally delivered rhTGF-,2 enhances bone ingrowth and bone regeneration at local and remote sites of skeletal injuryJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2001Dr. Sumner The purposes of the present study were to determine if recombinant human transforming growth factor-beta-2 (rhTGF-,2) enhances bone ingrowth into porous-coated implants and bone regeneration in gaps between the implant and surrounding host bone. The implants were placed bilaterally for four weeks in the proximal humeri of skeletally mature, adult male dogs in the presence of a 3-mm gap. In three treatment groups of animals, the test implant was treated with hydroxyapatite/tricalcium phosphate (HA/TCP) and rhTGF-,2 in buffer at a dose per implant of 1.2 ,g (n = 6), 12 ,g (n = 7), or 120 ,g (n = 7) and placed in the left humerus. In these same animals, an internal control implant treated only with HA/TCP and buffer was placed in the right humerus. In a non-TGF-, treated external control group of animals (n = 7), one implant was treated with HA/TCP while the contralateral implant was not treated with the ceramic. In vitro analyses showed that approximately 15% of the applied dose was released within 120 h with most of the release occurring in the first 24 h. The TGF-, treated implants had significantly more bone ingrowth than the controls with the greatest effect in the 12 ,g/implant group (a 2.2-fold increase over the paired internal control (P = 0.004) and a 4-fold increase over the external control (P < 0.001)). The TGF-, treated implants had significantly more bone formation in the gap than the controls with the greatest effect in the 12 and 120 ,g groups (1.8-fold increases over the paired internal controls (P = 0.003 and P = 0.012, respectively) and 2.8-fold increases over the external controls (P < 0.001 and P = 0.001, respectively)). Compared to the external controls, the internal control implants tended to have more bone ingrowth (1.9-fold increase, P = 0.066) and had significantly more bone formation in the gap (1.7-fold increase, P = 0.008). Thus, application of rhTGF-,2 to a porous-coated implant-stimulated local bone ingrowth and gap healing in a weakly dose-dependent manner and stimulated bone regeneration in the 3-mm gap surrounding the contralateral control implant, a site remote from the local treatment with the growth factor. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved. [source] Combined effects of wetting, drying, and microcrystalline cellulose type on the mechanical strength and disintegration of pelletsJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2009Maria Balaxi Abstract Effects of wetting and drying conditions on micromeritic, mechanical and disintegration properties of microcrystalline cellulose (MCC) pellets were evaluated. Extrusion/spheronization and three drying methods (fluidized bed, microwaves, and freeze drying) were applied using two wetting liquids (water or water-isopropanol 60:40 w/w) and three MCC types: (standard, silicified, and modified). Additionally, the effects of drying method were compared on highly porous pellets prepared by the incorporation and extraction of pore former (NaCl). It was found that the drying method has the greatest effect on the pellet size and porosity followed by the wetting liquid. The modification of MCC resulted in reduced water retention ability, implying hornification, increased porosity, reduced resistance to deformation and tensile strength of pellets. The disintegration time also decreased markedly due to the modification but only in the low porosity range <37%. Silicification increased greatly the disintegration time of the low porosity pellets (<14%). Combination of water-isopropanol, freeze drying and modified MCC gave the greatest increase in pellet size and porosity. The increase in pellet porosity caused exponential reduction in the resistance to deformation, tensile strength and disintegration time, as expected. Compared to fluidized bed, the freeze drying resulted in 20,30% higher porosity for pellets prepared without pore former and 6% for those with pore former, indicating the possibility of preparing highly porous pellets by employing freeze drying. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 98:676,689, 2009 [source] Controlled drug release from gels using surfactant aggregates: I. Effect of lipophilic interactions for a series of uncharged substancesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 9 2001Mattias Paulsson Abstract Gels are often used for the delivery of drugs because they have rheological properties that will give a long residence time. Most pharmaceutical gels consist of ,99% water and a polymer matrix that will not hinder the release of drugs with a small molecular weight. To fully take advantage of the residence time, it is necessary to have a sustained drug release. In this paper it is suggested that surfactant micelles can be used to control the release from gels. The in vitro release under physiological conditions of five parabens from four different poly(acrylic acid) gels (Carbopol 934, 940, 1342) and one gellan gum (Gelrite) gel was measured using a USP dissolution bath modified for gels, and the diffusion coefficients were calculated. The diffusion coefficient of uncharged parabens was generally lower in gels with lipophilic modifications, such as C1342, and the greatest effect was seen for butylparaben, with a diffusion that was 25% lower than that in C934 (lacking lipophilic modification). Addition of surfactant micelles to gels delayed the release of all the uncharged drugs in all types of gels studied. The slowest release was seen for butylparaben in a lipophilically modified gel with micelles present. The diffusion coefficient in such a system was almost 30 times smaller than that in C934 without micelles. © 2001 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 90:1216,1225, 2001 [source] Melatonin effect on bone metabolism in rats treated with methylprednisoloneJOURNAL OF PINEAL RESEARCH, Issue 4 2006Marta G. Ladizesky Abstract:, The present study was undertaken to examine the effect of melatonin (25 ,g/mL of drinking water, about 500 ,g/day) on a 10-wk long treatment of male rats with methylprednisolone (5 mg/kg s.c., 5 days/wk). Bone densitometry and mechanical properties, calcemia, phosphatemia and serum bone alkaline phosphatase activity and C-telopeptide fragments of collagen type I (CTX) were measured. Both melatonin and methylprednisolone decreased significantly body weight (BW) and the combination of both treatments resulted in the lowest BW values found. Consequently, all results were analyzed with BW as a covariate. Densitometrically, methylprednisolone augmented bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) in the entire skeleton, BMC in cortical bone, and BMC and BMD in trabecular bone. Melatonin increased BMC and BA in whole skeleton and BMC and BMD in trabecular bone. For BMC and BA of whole skeleton, BMC of cortical bone, and BMC and BMD of trabecular bone, the combination of glucocorticoids and melatonin resulted in the highest values observed. Femoral weight of rats receiving methylprednisolone or melatonin increased significantly and both treatments summated to achieve the greatest effect. In femoral biomechanical testing, methylprednisolone augmented ultimate load and work to failure significantly. Rats receiving the combined treatment of methylprednisolone and melatonin showed the highest values of work to failure. The circulating levels of CTX, an index of bone resorption, decreased after methylprednisolone or melatonin, both treatments summating to achieve the lowest CTX values found. Serum calcium increased after methylprednisolone and serum phosphorus decreased after treatment with methylprednisolone or melatonin while serum bone alkaline phosphatase levels remained unchanged. The results are compatible with the view that low doses of methylprednisolone or melatonin decrease bone resorption and have a bone-protecting effect. [source] Influence of Maillard reaction conditions on the antigenicity of bovine ,-lactalbumin using response surface methodologyJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 14 2009Guanhao Bu Abstract BACKGROUND: Maillard reaction can modify functional properties of proteins. Bovine ,-lactalbumin (,-LA) is often supplemented to the new generation of infant formulae, but it is considered to be a main allergen. However, there is little information on the effect of Maillard reaction on ,-LA antigenicity. The objective of this study was to investigate the influence of Maillard reaction on the antigenicity of ,-LA in conjugates of whey protein isolate (WPI) with glucose under different conditions of protein/sugar weight ratio (0.17,7.83), temperature (40,60 °C) and time (24,120 h) using response surface methodology. RESULTS: Conjugation of WPI with glucose markedly reduced the antigenicity of ,-LA. This reduction in antigenicity could be controlled by regulating the three independent variables weight ratio, temperature and time. A model of optimal reaction conditions for lower antigenicity of ,-LA was established. According to the model, the minimum antigenicity of ,-LA was achieved at 52.8 °C, 78 h and 5.96:1 WPI/glucose weight ratio. WPI/glucose weight ratio had the greatest effect on the antigenicity of ,-LA, while reaction temperature influenced ,-LA antigenicity to a lesser extent. CONCLUSION: Well-controlled Maillard reaction between WPI and glucose is an efficient method to reduce ,-LA antigencity. Copyright © 2009 Society of Chemical Industry [source] Effect of cultivar and roasting method on composition of roasted soybeansJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2009Emily L Boge Abstract BACKGROUND: The composition of raw soybeans and the roasting method have an important impact on the quality of roasted soybeans. The objective of the study was to determine the effect of food-grade soybean cultivars (IA 2064, IA 1008, IA 1008LF, Prairie Brand 299, Asgrow 2247) and roasting method (oil- and dry-roasting) on the composition of roasted soybeans. RESULTS: Moisture content decreased after roasting, with oil-roasted soybeans having a significantly lower moisture content than the dry-roasted soybeans. With the exception of the low linolenic acid cultivar (IA 2064), there were no significant differences in total lipid and fatty acid contents of the five cultivars. Oil-roasted soybeans had significantly higher lipid content than raw and dry-roasted soybeans owing to the absorption of oil. The soluble sugars and free amino acids contents of the five soybean cultivars were not significantly different. Decreases in the contents of free amino acids, but not soluble sugars, occurred during roasting. Greater reductions were seen in oil-roasted soybeans because of the higher roasting temperature. CONCLUSION: Roasting method, rather than cultivar, had the greatest effect on the composition of roasted soybeans. The food-grade soybean cultivars evaluated in this study were similar in composition. Copyright © 2009 Society of Chemical Industry [source] Effects of cultivar, root weight, storage and boiling on carbohydrate content in carrots (Daucus carota L)JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 3 2005E Margareta G-L Nyman Abstract The effects of cultivar (n = 4), root weight (n = 4), storage (5 months) and boiling (7 min) and their interactions on the content of dry matter and carbohydrates were studied and ranked in carrots. Boiling had the greatest effect and had an influence on all variables except the ratio between sucrose and the monosaccharides glucose and fructose. The choice of cultivar was also of great importance as regards glucose, fructose and sucrose content, while dietary fibre and dry matter were much less affected, or even unaffected, by this factor. Root weight and storage were consistently of less significance than boiling and cultivar. Thus dietary fibre solubility, fructose content and the ratio between sucrose and the monosaccharides glucose and fructose were independent of the root weight, while storage had no impact on the dry matter content. After storage the cultivar Lonto had lost more dry matter than the other cultivars (10% versus mean 1% for the others, P = 0.009) and the sugar ratio between sucrose and the monosaccharides glucose and fructose had increased in the cultivar Amarant, while it decreased in the other cultivars (P < 0.001). Furthermore, Amarant had a lower loss of sugars (35%) following boiling than the other cultivars (mean 39%, P = 0.002). Storage and boiling interacted concerning soluble and insoluble dietary fibre, fibre solubility and glucose content. It is concluded that the various factors (especially boiling and cultivar) gave rise to such differences in carbohydrate content and composition that they might be of nutritional importance. The results may thus provide a basis for selecting raw material when studying possible health effects of carrots. Copyright © 2004 Society of Chemical Industry [source] Influence of operating conditions on friction and temperature characteristics of a wet clutch engagementLUBRICATION SCIENCE, Issue 2 2000Mikael HolgersonArticle first published online: 9 MAR 200 Abstract To optimise the gear change in automatic transmissions, more knowledge is needed of the engagement behaviour of wet clutches. A factorial design investigation of the engagement of a wet clutch has been carried out. The friction and temperature characteristics have been studied. The experiments were carried out in an apparatus that can vary sliding velocity, drive torque, inertia, force rate, and lubricant flow. The results show how these parameters affect the response data: engagement time, developed energy, temperature rise, maximum torque, maximum power, static friction, dynamic friction, and initial friction. There are interaction effects between some of the input parameters, but they are relatively small. The friction coefficient varies over time but is independent of the input parameters, except for dynamic friction, which decreases with increasing sliding velocity, drive torque, and inertia. The temperature rise was found to be proportional to developed energy and both these were most affected by sliding velocity. The drive torque and force rate have the greatest effect on the engagement time. [source] Mass transport studies of different additives in polyamide and exfoliated nanocomposite polyamide films for food industryPACKAGING TECHNOLOGY AND SCIENCE, Issue 2 2010David Antonio Pereira de Abreu Abstract The development of new food packaging films through the incorporation of nanoparticles, and the effect of the nanoparticles on the process of migration of the substances used in manufacturing the new films is expected to lead to an improvement in the shelf life of food and thus, consumer safety and health. In recent years, attention has focused on nanocomposites because these compounds often exhibit unexpected hybrid properties derived from synergistic reactions between nanoparticles and the polymeric matrix. The exfoliation of nanoclays in polyamide film provides a film with better barrier properties than that obtained through the intercalation of nanoclays. Migration of chemicals from food packaging into food may produce potential adverse health effects because of exposure to toxic compounds. The present study addressed the migration of caprolactam, 5-Chloro-2-(2,4-dichlorophenoxy)phenol (triclosan) and trans,trans-1,4-diphenyl-1,3-butadiene (DPBD) from polyamide and polyamide-nanoclays to different types of food simulants. The values for limit of detection (LOD) obtained for caprolactam, triclosan and DPBD was 0.5,mg/L, 0.02,mg/L and 0.01,mg/L, respectively. Furthermore, instrumental precision was evaluated through repeatability injections, resulting in relative standard deviations lower than 3.08%. Diffusion coefficients were calculated according to a mathematical model based on Fick's Second Law, and the results were discussed in terms of the parameters that may have the greatest effect on migration. The presence of polymer nanoparticles was found to slow down the rate of migration of substances from the matrix polymer into the food up to six times. Copyright © 2009 John Wiley & Sons, Ltd. [source] Some alternatives in the statistical analysis of sickness absenceAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 10 2009Albert Navarro Abstract Purpose Sickness absence (SA) is a commonly used outcome in occupational health cohort studies. Without the use of statistical techniques that take into account that SA is a recurrent event, the probability of obtaining biased estimates of the effects related to SA is very high. The objective of this article is to examine the application of marginal models, comparing them to count-based models, when the outcome of interest is SA. Methods By re-sampling the data of a reference study, 1,000 samples of 1,200 individuals were generated. In each of these samples, the coefficients of two factors were estimated by fitting various models: Poisson, Negative Binomial, standard Cox model for a first occurrence, Andersen,Gill and Prentice,Williams,Peterson. Results In general, differences among the models are observed in the estimates of variances and coefficients, as well as in their distribution. Specifically, the Poisson model estimates the greatest effect for both coefficients (IRR,=,1.17 and IRR,=,1.60), and the Prentice,Williams,Peterson the least effect (HR,=,1.01 and HR,=,1.26). Conclusions Whenever possible, the instantaneous form of analysis should be used for occurrences of a recurrent event. Collection of study data should be organized in order to permit recording of the most complete information possible, particularly regarding event occurrences. This should allow the presence of within-individual heterogeneity and/or occurrence dependency to be studied, and would further permit the most appropriate model to be chosen. When there is occurrence dependence, the choice of a model using the specific baseline hazard seems to be appropriate. Am. J. Ind. Med. 52:811,816, 2009. © 2009 Wiley-Liss, Inc. [source] Stomatal sensitivity to vapour pressure difference over a subambient to elevated CO2 gradient in a C3/C4 grasslandPLANT CELL & ENVIRONMENT, Issue 8 2003H. MAHERALI ABSTRACT In the present study the response of stomatal conductance (gs) to increasing leaf-to-air vapour pressure difference (D) in early season C3 (Bromus japonicus) and late season C4 (Bothriochloa ischaemum) grasses grown in the field across a range of CO2 (200,550 µmol mol,1) was examined. Stomatal sensitivity to D was calculated as the slope of the response of gs to the natural log of externally manipulated D (dgs/dlnD). Increasing D and CO2 significantly reduced gs in both species. Increasing CO2 caused a significant decrease in stomatal sensitivity to D in Br. japonicus, but not in Bo. ischaemum. The decrease in stomatal sensitivity to D at high CO2 for Br. japonicus fit theoretical expectations of a hydraulic model of stomatal regulation, in which gs varies to maintain constant transpiration and leaf water potential. The weaker stomatal sensitivity to D in Bo. ischaemum suggested that stomatal regulation of leaf water potential was poor in this species, or that non-hydraulic signals influenced guard cell behaviour. Photosynthesis (A) declined with increasing D in both species, but analyses of the ratio of intercellular to atmospheric CO2 (Ci/Ca) suggested that stomatal limitation of A occurred only in Br. japonicus. Rising CO2 had the greatest effect on gs and A in Br. japonicus at low D. In contrast, the strength of stomatal and photosynthetic responses to CO2 were not affected by D in Bo. ischaemum. Carbon and water dynamics in this grassland are dominated by a seasonal transition from C3 to C4 photosynthesis. Interspecific variation in the response of gs to D therefore has implications for predicting seasonal ecosystem responses to CO2. [source] Economic Development, Gender Inequality, and Demographic Outcomes: Evidence from IndiaPOPULATION AND DEVELOPMENT REVIEW, Issue 2 2006Prabir C. Bhattacharya This article examines the determinants of fertility, child mortality, and female disadvantage in child survival in India, using a district-level panel data set linking 1981 and 1991 censuses. The results question the dominant view that variables directly related to women's agency (specifically, the female literacy rate and the female labor force participation rate) have played the crucial roles here. Instead, variables reflecting the general level of development and modernization are shown to have had the greatest effect in reducing fertility and child mortality during the period of the study. Both economic development and women's agency are seen to have had significant effects in reducing the female disadvantage in child survival. The results suggest, however, that with continued economic development, the two women's agency variables lose their significance in influencing this disadvantage. The policy implications of these findings are considered. [source] The Role of Procedural Controls in OSHA's Ergonomics RulemakingPUBLIC ADMINISTRATION REVIEW, Issue 4 2007Stuart Shapiro Few, if any, regulations over the past decade have received as much publicity or engendered such controversy as the ergonomics regulation of the Occupational Health and Safety Administration (OSHA). Some may see the ergonomics rule as the paradigmatic instance of procedural hurdles holding up and eventually destroying a regulation. This article examines the role that procedure played in the ergonomics rulemaking. Lessons are drawn from an analysis of the four publicly available versions of the regulation and interviews with seven high-ranking officials at OSHA and the Small Business Administration. Of the procedural hurdles faced by OSHA, the notice-and-comment requirement had the largest impact on the final rule. OMB review and requirements to conduct a cost-benefit analysis served largely as a fire alarm to political overseers, and the required small business panel had largely symbolic effects. The more traditional control of congressional budgetary oversight had the greatest effect by delaying the rule for three years, and thus eventually doomed OSHA's attempts to regulate. [source] | ||||||||||||||||||||||||||||||||||||||||