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Rising
Terms modified by Rising Selected AbstractsThe effect of rising and sitting trot on back movements and head-neck position of the horseEQUINE VETERINARY JOURNAL, Issue 5 2009P. de COCQ Summary Reason for performing study: During trot, the rider can either rise from the saddle during every stride or remain seated. Rising trot is used frequently because it is widely assumed that it decreases the loading of the equine back. This has, however, not been demonstrated in an objective study. Objective: To determine the effects of rising and sitting trot on the movements of the horse. Hypothesis: Sitting trot has more extending effect on the horse's back than rising trot and also results in a higher head and neck position. Methods: Twelve horses and one rider were used. Kinematic data were captured at trot during over ground locomotion under 3 conditions: unloaded, rising trot and sitting trot. Back movements were calculated using a previously described method with a correction for trunk position. Head-neck position was expressed as extension and flexion of C1, C3 and C6, and vertical displacement of C1 and the bit. Results: Sitting trot had an overall extending effect on the back of horses when compared to the unloaded situation. In rising trot: the maximal flexion of the back was similar to the unloaded situation, while the maximal extension was similar to sitting trot; lateral bending of the back was larger than during the unloaded situation and sitting trot; and the horses held their heads lower than in the other conditions. The angle of C6 was more flexed in rising than in sitting trot. Conclusions and clinical relevance: The back movement during rising trot showed characteristics of both sitting trot and the unloaded condition. As the same maximal extension of the back is reached during rising and sitting trot, there is no reason to believe that rising trot was less challenging for the back. [source] Measuring sexual size dimorphism in birdsIBIS, Issue 3 2003Julian G. Greenwood Numerous studies have examined sexual size dimorphism in birds and speculated upon the reasons for its existence. Whilst most studies have focused on individual species or groups of related species, a few have attempted to disentangle the various hypotheses that have been put forward to explain its occurrence. Typical of the latter studies is that by Jehl and Murray (1986), in which they argued that sexual size dimorphism was primarily the result of sexual selection (see also Bennett & Owens 2002). Although some studies have looked at patterns in sexual size dimorphism without calculating a figure to represent the difference (e.g. Amadon 1959), most have examined measurements of birds and used these to calculate such a figure. Traditionally in such studies, measurements used have included wing-length, culmen-length, tarsus-length and mass, although McGillivray (1989) took the sum of 18 skeletal measurements and used their male and female means to determine sexual size dimorphism. Wing-length has commonly been used to determine sexual size dimorphism, although lack of repeatability of measurements may render it less useful than skeletal measurements like tarsus-length as in studies of Dunlin Calidris alpina (Blomqvist et al. 1997) and Savannah Sparrows Passerculus sandwichensis (Rising & Somers 1989); however, Gosler et al. (1998) found wing-length measurements to be more repeatable than other metrics in a group of 27 passerines. [source] Diverting with Benevolent Military Force: Reducing Risks and Rising above Strategic BehaviorINTERNATIONAL STUDIES QUARTERLY, Issue 2 2007EMIZET F. KISANGANI Research on the diversionary use of force has burgeoned in recent years, but the literature remains divided. This paper attempts to reconcile extant findings by advancing a new theoretical framework for diversionary force centered on the agenda-setting literature. It expands the conventional conception of diversionary behavior and distinguishes the benevolent use of force over low politics issues (which we term socioeconomic interventions, SEI) from belligerent force used over high politics issues (which we term politico-strategic interventions, PSI). This expansion also refines our understanding of strategic conflict avoidance (SCA). Using Zero-Inflated Poisson (ZIP) regression on 140 countries from 1950 to 1996, we find that democracies and mixed regimes tend to use SEI for diversion even though strategic conflict avoidance does not prevent them from using PSI. We further find that autocracies do not externalize their internal problems with either type of armed force and that, surprisingly, strategic conflict avoidance may constrain autocracies suffering economic decline. These outcomes suggest that our theory has utility and that research on both diversion and SCA would benefit from further theoretical refinement. [source] Epidemic of Cesarean Section at the General, Private and University Hospitals in ThailandJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2000Dr. Boonsri Chanrachakul Abstract Objective: To undertake a survey of cesarean section in the general, private and university hospitals in Thailand. Methods: Postal questionnaires were sent to all the general, private and university hospitals with 200 beds or more. The questionnaires were prepared to find out the percentage, the indications and the trend of cesarean delivery, the measures taken to decrease cesarean section rate, and the practice of external cephalic version (ECV) and vaginal birth after cesarean section (VBAC) in the hospitals. Results: The overall response rate was 88%. Mean cesarean section rates were 24, 48, and 22% in the general, private and university hospitals, respectively. Cesarean section rates in most of the hospitals were increased in the past 5 years namely 78% in the general hospitals, 50% in the private hospitals, 66% in the university hospitals. However, only 38% of the hospitals had measures to regulate this operation. Repeated cesarean section was the most common indication in the private (63%) and the university hospitals (88%) while failure to progress was the most common indication in the general hospitals (55%). ECV and VBAC were performed in 26 and 12% of the hospitals. They were, however, not the standard practices. Conclusion: Rising of cesarean section rate without any measure to regulate it is the problem in the developing countries. Standardised labor management and reduction of unnecessary primary cesarean section will automatically reduce repeated operation and overall cesarean section. [source] Rising jet-inflated bubbles in clusters of galaxiesMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY: LETTERS (ELECTRONIC), Issue 1 2008Assaf Sternberg ABSTRACT We conduct two-dimensional axisymmetric (referred to as 2.5D) hydrodynamical numerical simulations of bubble evolution in clusters of galaxies. We inflate bubbles using slow, massive jets with a wide opening angle, and follow their evolution as they rise through the intracluster medium. We find that these jet-inflated bubbles are quite stable, and can reach large distances in the cluster while maintaining their basic structure. The stability of the jet-inflated bubble comes mainly from the dense shell that forms around it during its inflation stage, and from the outward momentum of the bubble and shell. On the contrary, bubbles that are inserted by hand on to the grid and not inflated by a jet, i.e. an artificial bubble, lack these stabilizing factors; therefore, they are rapidly destroyed. The stability of the jet-inflated bubble removes the demand for stabilizing magnetic fields in the bubble. [source] The Impact of the 1916 Rising: Among the Nations by Ruán O'Donnell (ed.)NATIONS AND NATIONALISM, Issue 4 2009CHRISTOPHER MOFFAT [source] "Atlantic Revolution" or Local Difficulty: Aspects of Revolt in Brazil, 1780,1880AUSTRALIAN JOURNAL OF POLITICS AND HISTORY, Issue 3 2010Dick Geary It has become commonplace to argue that the ideals of the Enlightenment, the American War of Independence and the French Revolution inspired revolutionary struggles on both sides of the Atlantic and even played an increasing role in the inspiration of slave revolts in the Americas. This paper tests this hypothesis against two kinds of upheaval, namely slave revolt in Brazil between 1780 and 1850 and artisan protest in the so-called Praiera Rising in Brazilian Recife in 1848/9, seen by Hobsbawm and others (including some Brazilian historians) as a South American variant of the Parisian upheavals of the same year. The analysis of slave revolts in this paper, on the other hand, concludes that they were rarely inspired by Western discourse, as they were overwhelmingly the work of African slaves, who relied on African , or to be more precise , Afro-Brazilian traditions, including local cults and African Islam. In so far as there was an "Atlantic Revolution" in this case, therefore, it came from the South and not the North Atlantic. In the case of the Praiera the paper further demonstrates that the demands of free and freed Brazilian artisans for "work for all Brazilians" and the "nationalisation of the retail trade" were not inspired by the same kind of radical, anti-merchant ideology as their Parisian counterparts but were primarily driven by hostility to the competition of both slave artisans and an influx of Portuguese craftsmen. This difference it explains by the different meaning of labour in slave and non-slave society. [source] Acronycal Risings in Babylonian AstronomyCENTAURUS, Issue 2 2004Louise Hollywood First page of article [source] Particle size of powders under hydrothermal conditionsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2003Wen-Jun Li Abstract Various non-oxide (CuI, AgI, AgCl, PbS, CuS and ZnS) and oxide (ZnO, TiO2, SnO2, CeO2 and ZrO2) powders were prepared under hydrothermal conditions to investigate the effects of temperature, pH and precursors on the particle size of powders. It was found that the particle sizes of PbS, CuS and ZnS powders were much smaller than that of CuI, AgI and AgCl powders prepared under the same conditions. The particle sizes of TiO2, SnO2, CeO2 and ZrO2 powders are much smaller than that of ZnO powders prepared under the same conditions. It is concluded that the solution conditions have a certain effect on the particle size of powders under the hydrothermal conditions. The particle size of powders increased with the rising of temperature. Additional factors affecting the particle size were uncovered through studying the nucleation mechanism. The particle size was mainly related to the Madelung constant and the electric charge number of ions. Powders with smaller particle size resulted from systems that possessed the larger Madelung constant and ionic charge number. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Recent time trends in levels of self-reported anxiety, mental health service use and suicidal behaviour in StockholmACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2010K. Kosidou Kosidou K, Magnusson C, Mittendorfer-Rutz E, Hallqvist J, Gumpert CH, Idrizbegovic S, Dal H, Dalman C. Recent time trends in levels of self-reported anxiety, mental health service use and suicidal behaviour in Stockholm. Objective:, To investigate recent time trends in several indicators of mental ill-health and the patterning of these indicators between genders and younger vs. older individuals in Stockholm County. Method:, Several indicators were used; self-reported anxiety from the Swedish Survey of Living Conditions, information on psychiatric in-patient and out-patient care, attempted and completed suicides from national and regional registers. Gender- and age-specific trends were compared for the time period of 1997,2006. Results:, Self-reported anxiety and psychiatric service use increased among young individuals of both genders, while attempted suicides increased only among young women. By contrast, these indicators decreased or remained stable in the older age group from year 2001 and onwards. Conclusion:, Our data indicate a rising, and highly prevalent, mental ill-health among the young in Stockholm County, a region representative of urbanized, secular Western societies. [source] The epidemiology of autistic spectrum disorders: is the prevalence rising?DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2002Lorna Wing Abstract For decades after Kanner's original paper on the subject was published in 1943, autism was generally considered to be a rare condition with a prevalence of around 2,4 per 10,000 children. Then, studies carried out in the late 1990s and the present century reported annual rises in incidence of autism in pre-school children, based on age of diagnosis, and increases in the age-specific prevalence rates in children. Prevalence rates of up to 60 per 10,000 for autism and even more for the whole autistic spectrum were reported. Reasons for these increases are discussed. They include changes in diagnostic criteria, development of the concept of the wide autistic spectrum, different methods used in studies, growing awareness and knowledge among parents and professional workers and the development of specialist services, as well as the possibility of a true increase in numbers. Various environmental causes for a genuine rise in incidence have been suggested, including the triple vaccine for measles, mumps and rubella (MMR]. Not one of the possible environmental causes, including MMR, has been confirmed by independent scientific investigation, whereas there is strong evidence that complex genetic factors play a major role in etiology. The evidence suggests that the majority, if not all, of the reported rise in incidence and prevalence is due to changes in diagnostic criteria and increasing awareness and recognition of autistic spectrum disorders. Whether there is also a genuine rise in incidence remains an open question. MRDD Research Reviews 2002;8:151,161. © 2002 Wiley-Liss, Inc. [source] Impacts of federal precursor chemical regulations on methamphetamine arrestsADDICTION, Issue 4 2005James K. Cunningham ABSTRACT Aims The US government regulated precursor chemicals, ephedrine and pseudoephedrine, multiple times to limit methamphetamine production/availability and thus methamphetamine problems. Research has found that the regulations reduced methamphetamine hospital admissions, but authors have argued that other problems were unaffected. This study examines whether the regulations impacted methamphetamine arrests. Design ARIMA-intervention time-series analysis with control series. Setting California (1982,2001). Measurements Dependent variable series: monthly methamphetamine arrests. Control series: monthly marijuana arrests and cocaine/heroin arrests. Interventions Bulk powder ephedrine and pseudoephedrine: regulated November 1989. Products containing ephedrine as the single active medicinal ingredient: regulated August 1995. Pseudoephedrine products: regulated October 1997. Large-scale producers used ephedrine and pseudoephedrine in these forms. Ephedrine combined with other active medicinal ingredients (e.g. various cold medicines),used mainly by small-scale producers: regulated October 1996. Findings The regulation targeting small-scale producers (1996) had no significant impact. In contrast, methamphetamine arrests stopped rising and dropped 31% to 45% each of the three times precursor chemicals used by large-scale producers were regulated. Within 3 years of the bulk powder regulation (1989) and again within 2 years of the ephedrine single ingredient regulation (1995), arrests fully rebounded. During the 4 years following the last regulation (pseudoephedrine products, 1997) arrests only partially rebounded. These effects parallel those reported on hospital admissions. The control series were generally unaffected. Conclusions Precursor regulations targeting large-scale producers impacted methamphetamine arrests, a criminal justice problem, much as they impacted the public health problem of methamphetamine hospital admissions. Ongoing research is needed to determine whether these problems eventually fully rebound from the last regulation. [source] The effect of rising and sitting trot on back movements and head-neck position of the horseEQUINE VETERINARY JOURNAL, Issue 5 2009P. de COCQ Summary Reason for performing study: During trot, the rider can either rise from the saddle during every stride or remain seated. Rising trot is used frequently because it is widely assumed that it decreases the loading of the equine back. This has, however, not been demonstrated in an objective study. Objective: To determine the effects of rising and sitting trot on the movements of the horse. Hypothesis: Sitting trot has more extending effect on the horse's back than rising trot and also results in a higher head and neck position. Methods: Twelve horses and one rider were used. Kinematic data were captured at trot during over ground locomotion under 3 conditions: unloaded, rising trot and sitting trot. Back movements were calculated using a previously described method with a correction for trunk position. Head-neck position was expressed as extension and flexion of C1, C3 and C6, and vertical displacement of C1 and the bit. Results: Sitting trot had an overall extending effect on the back of horses when compared to the unloaded situation. In rising trot: the maximal flexion of the back was similar to the unloaded situation, while the maximal extension was similar to sitting trot; lateral bending of the back was larger than during the unloaded situation and sitting trot; and the horses held their heads lower than in the other conditions. The angle of C6 was more flexed in rising than in sitting trot. Conclusions and clinical relevance: The back movement during rising trot showed characteristics of both sitting trot and the unloaded condition. As the same maximal extension of the back is reached during rising and sitting trot, there is no reason to believe that rising trot was less challenging for the back. [source] Effect of auditory cortex lesions on the discrimination of frequency-modulated tones in ratsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 6 2006Natalia Rybalko Abstract The lateralization of functions to individual hemispheres of the mammalian brain remains, with the exception of the human brain, unresolved. The aim of this work was to investigate the ability to discriminate between falling and rising frequency-modulated (FM) stimuli in rats with unilateral or bilateral lesions of the auditory cortex (AC). Using an avoidance conditioning procedure, thirsty rats were trained to drink in the presence of a rising FM tone and to stop drinking when a falling FM tone was presented. Rats with a lesion of the AC were able to learn to discriminate between rising and falling FM tones; however, they performed significantly worse than did control rats. A greater deficit in the ability to discriminate the direction of frequency modulation was observed in rats with a right or bilateral AC lesion. The discrimination performance (DP) in these rats was significantly worse than the DP in rats with a left AC lesion. Animals with a right or bilateral AC lesion improved their DP mainly by recognizing the pitch at the beginning of the stimuli. The lesioning of the AC in trained animals caused a significant decrease in DP, down to chance levels. Retraining resulted in a significant increase in DP in rats with a left AC lesion; animals with a right lesion improved only slightly. The results demonstrate a hemispheric asymmetry of the rat AC in the recognition of FM stimuli and indicate the dominance of the right AC in the discrimination of the direction of frequency modulation. [source] Temperature and soil moisture effects on dissolved organic matter release from a moorland Podzol O horizon under field and controlled laboratory conditionsEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2007M. I. Stutter Summary Organic upland soils store large amounts of humified organic matter. The mechanisms controlling the leaching of this C pool are not completely understood. To examine the effects of temperature and microbial cycling on C leaching, we incubated five unvegetated soil cores from a Podzol O horizon (from NE Scotland), over a simulated natural temperature cycle for 1 year, whilst maintaining a constant soil moisture content. Soil cores were leached with artificial rain (177 mm each, monthly) and the leachates analysed for dissolved organic carbon (DOC) and their specific C-normalized UV absorbance determined (SUVA, 285 nm). Monthly values of respiration of the incubated soils were determined as CO2 efflux. To examine the effects of vegetation C inputs and soil moisture, in addition to temperature, we sampled O horizon pore waters in situ and collected five additional field soil cores every month. The field cores were leached under controlled laboratory conditions. Hysteresis in the monthly amount of DOC leached from field cores resulted in greater DOC on the rising, than falling temperature phases. This hysteresis suggested that photosynthetic C stimulated greater DOC losses in early summer, whereas limitations in the availability of soil moisture in late summer suppressed microbial decomposition and DOC loss. Greater DOC concentrations of in-situ pore waters than for any core leachates were attributed to the effects of soil drying and physico-chemical processes in the field. Variation in the respiration rates for the incubated soils was related to temperature, and respiration provided a greater pathway of C loss (44 g C m,2 year,1) than DOC (7.2 g C m,2 year,1). Changes in SUVA over spring and summer observed in all experimental systems were related to the period of increased temperature. During this time, DOC became less aromatic, which suggests that lower molecular weight labile compounds were not completely mineralized. The ultimate DOC source appears to be the incomplete microbial decomposition of recalcitrant humified C. In warmer periods, any labile C that is not respired is leached, but in autumn either labile C production ceases, or it is sequestered in soil biomass. [source] Seasonal and interannual variation of bacterial production in lowland rivers of the Orinoco basinFRESHWATER BIOLOGY, Issue 11 2004María M. Castillo Summary 1. We examined the influence of hydrologic seasonality on temporal variation of planktonic bacterial production (BP) in relatively undisturbed lowland rivers of the middle Orinoco basin, Venezuela. We sampled two clearwater and two blackwater rivers over 2 years for dissolved organic carbon (DOC), chlorophyll, phosphorus and bacterial abundance to determine their relationship to temporal variation in BP. 2. Dissolved organic carbon concentration was greater in blackwater (543,664 ,m) than in clearwater rivers (184,240 ,m), and was generally higher during periods of rising and high water compared with low water. Chlorophyll concentration peaked (3 ,g L,1) during the first year of study when discharge was lowest, particularly in blackwater rivers. Soluble reactive phosphorus (SRP) was very low in the study rivers (<3.8 ,g L,1) and concentration increased during low water. 3. Average BP was higher in clearwater (0.20,0.26 ,g C L,1 h,1) than in blackwater rivers (0.14,0.17 ,g C L,1 h,1), although mean bacterial abundance was similar among rivers (0.6,0.8 × 106 cells mL,1). 4. Periods of higher chlorophyll a concentration (low water) or flushing of terrestrial organic material (rising water) were accompanied by higher BP, while low BP was observed during the period of high water. 5. Interannual variation in BP was influenced by variations in discharge related to El Niño Southern Oscillation events. 6. Seasonal variation in BP in the study rivers and other tropical systems was relatively small compared with seasonal variation in temperate rivers and lakes. In addition to the low seasonal variation of temperature in the tropics, low overall human disturbance could result in less variation in the inputs of nutrients and carbon to the study rivers compared with more disturbed temperate systems. [source] Invertebrate communities associated with a native (Vallisneria americana) and an alien (Trapa natans) macrophyte in a large riverFRESHWATER BIOLOGY, Issue 11 2003David L. Strayer Summary 1. We used a corer and a Downing box sampler to sample macroinvertebrates living on and beneath the introduced Trapa natans and the native Vallisneria americana in the freshwater tidal Hudson River, New York. 2. Densities of macroinvertebrates were higher in Trapa than in Vallisneria, and higher in the interior of plant beds than at their edges. These effects were largely a result of high plant biomass in Trapa beds and in bed interiors (the plants have similar surface area per unit mass). 3. The composition of both epiphytic and benthic macroinvertebrates differed distinctly between Trapa and Vallisneria, and also seasonally. 4. These compositional differences were not easily interpretable as rising from possible differences in oxygen concentrations, fish predation, or water circulation in the two macrophytes. 5. Sida crystallina (Cladocera) collected from Trapa contained more haemoglobin than those collected from Vallisneria. 6. The replacement of Vallisneria by Trapa in the Hudson probably increased system-wide biodiversity and food for fish, although macroinvertebrates in Trapa beds may not be readily available to fish because of low oxygen concentration there. [source] Management of type 2 diabetes: the GLP-1 pathwayFUTURE PRESCRIBER, Issue 3 2008Abd A Tahrani MMedSci Type 2 diabetes mellitus (T2DM) is a major challenge to healthcare systems around the world, with an estimated prevalence of 6% (246 million) in 2007 rising to 7.3% (380 million) in 2025 worldwide.1,5 In this article, the authors consider the significance of the GLP-1 path-way in the management of T2DM, and some of the advantages of incretin-based therapy. Copyright © 2008 John Wiley & Sons, Ltd. [source] New light on ,the commotion time' of 1549: the Oxfordshire rising*HISTORICAL RESEARCH, Issue 218 2009Katherine Halliday In July 1549 the Oxfordshire commons rose in large number, and without gentry support. Somewhere in the region of several hundred armed participants marched from the south-east to the north-west of the county, pillaging parks as they went, until eventually retreating into the town of Chipping Norton. The principal catalyst for the 1549 rising seems, given the rebels' targets and timing, to have been the common perception that the goods of the county's churches were about to be seized by the commissioners for church goods. Consequently, Oxfordshire's rebels did not head for London , they were not opposing religious reforms per se, but were contesting the Edwardian reforms as they had been imposed within their parishes. [source] Fashioning victims: Dr. Henry Jones and the plight of Irish Protestants, 1642HISTORICAL RESEARCH, Issue 186 2001Joseph Cope This article explores Dr. Henry Jones's work in conveying first-hand testimony on the Irish rising to English audiences in 1642. It compares Jones's Remonstrance of Diverse Remarkable Passages Concerning the Church and Kingdom of Ireland with the archival materials from which he drew his information. In order to persuade the English parliament and the English people to support charitable projects for Ireland's poor, Jones needed to portray the victims of the rising in a positive light. The resulting image of deserving war victims was broadly sympathetic but in fact reflected a distorted view of the experiences of those despoiled in the rebellion. [source] Water table and transpiration dynamics in a seasonally inundated Melaleuca quinquenervia forest, north Queensland, AustraliaHYDROLOGICAL PROCESSES, Issue 16 2008David McJannet Abstract Water table fluctuations and transpiration were monitored in a seasonally inundated Melaleuca quinquenervia floodplain forest at Cowley Beach, north Queensland, Australia. Techniques were developed to reconstruct inundation duration and seasonal and inter-annual variability at this site using long-term stream flow data. It was estimated that the median duration of inundation in any year was 75 days with maximum and minimum durations of 167 days and 8 days, respectively. Measurements of individual tree transpiration using heat-pulse techniques showed a strong relationship between tree size and tree water use, which was used for scaling to stand transpiration. Stand transpiration rates were found to be closely tied to atmospheric drivers of evaporation, and transpiration of M. quinquenervia was found to be unaffected by inundation. This ability to transpire during inundation may be due to physiological adaptations of this species. These adaptations are believed to include dynamic root systems that can quickly respond to rising and falling water tables and dense networks of fine apogeotropic roots, which grow on and within the papery bark. Rates of stand transpiration remained low throughout the study (0·46 mm d,1, 164 mm y,1) despite the fact that transpiration was not limited by solar energy inputs or soil moisture deficit. Low stand transpiration was attributed to the low density, stunted nature and small sapwood area of trees at this site. Copyright © 2007 John Wiley & Sons, Ltd. [source] Geochemical weathering at the bed of Haut Glacier d'Arolla, Switzerland,a new modelHYDROLOGICAL PROCESSES, Issue 5 2002M. Tranter Waters were sampled from 17 boreholes at Haut Glacier d'Arolla during the 1993 and 1994 ablation seasons. Three types of concentrated subglacial water were identified, based on the relative proportions of Ca2+, HCO3, and SO42, to Si. Type A waters are the most solute rich and have the lowest relative proportion of Si. They are believed to form in hydrologically inefficient areas of a distributed drainage system. Most solute is obtained from coupled sulphide oxidation and carbonate dissolution (SO,CD). It is possible that there is a subglacial source of O2, perhaps from gas bubbles released during regelation, because the high SO42, levels found (up to 1200 µeq/L) are greater than could be achieved if sulphides are oxidized by oxygen in saturated water at 0 °C (c.414 µeq/L). A more likely alternative is that sulphide is oxidized by Fe3+ in anoxic environments. If this is the case, exchange reactions involving FeIII and FeII from silicates are possible. These have the potential to generate relatively high concentrations of HCO3, with respect to SO42,. Formation of secondary weathering products, such as clays, may explain the low Si concentrations of Type A waters. Type B waters were the most frequently sampled subglacial water. They are believed to be representative of waters flowing in more efficient parts of a distributed drainage system. Residence time and reaction kinetics help determine the solute composition of these waters. The initial water,rock reactions are carbonate and silicate hydrolysis, and there is exchange of divalent cations from solution for monovalent cations held on surface exchange sites. Hydrolysis is followed by SO,CD. The SO42, concentrations usually are <414 µeq/L, although some range up to 580 µeq/L, which suggests that elements of the distributed drainage system may become anoxic. Type C waters were the most dilute, yet they were very turbid. Their chemical composition is characterized by low SO42, : HCO3, ratios and high pH. Type C waters were usually artefacts of the borehole chemical weathering environment. True Type C waters are believed to flow through sulphide-poor basal debris, particularly in the channel marginal zone. The composition of bulk runoff was most similar to diluted Type B waters at high discharge, and was similar to a mixture of Type B and C waters at lower discharge. These observations suggest that some supraglacial meltwaters input to the bed are stored temporarily in the channel marginal zone during rising discharge and are released during declining flow. Little of the subglacial chemical weathering we infer is associated with the sequestration of atmospheric CO2. The progression of reactions is from carbonate and silicate hydrolysis, through sulphide oxidation by first oxygen and then FeIII, which drives further carbonate and silicate weathering. A crude estimate of the ratio of carbonate to silicate weathering following hydrolysis is 4 : 1. We speculate that microbial oxidation of organic carbon also may occur. Both sulphide oxidation and microbial oxidation of organic carbon are likely to drive the bed towards suboxic conditions. Hence, we believe that subglacial chemical weathering does not sequester significant quantities of atmospheric CO2 and that one of the key controls on the rate and magnitude of solute acquisition is microbial activity, which catalyses the reduction of FeIII and the oxidation of FeS2. Copyright © 2002 John Wiley & Sons, Ltd. [source] A volume-of-fluid method for incompressible free surface flowsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 12 2009I. R. Park Abstract This paper proposes a hybrid volume-of-fluid (VOF) level-set method for simulating incompressible two-phase flows. Motion of the free surface is represented by a VOF algorithm that uses high resolution differencing schemes to algebraically preserve both the sharpness of interface and the boundedness of volume fraction. The VOF method is specifically based on a simple order high resolution scheme lower than that of a comparable method, but still leading to a nearly equivalent order of accuracy. Retaining the mass conservation property, the hybrid algorithm couples the proposed VOF method with a level-set distancing algorithm in an implicit manner when the normal and the curvature of the interface need to be accurate for consideration of surface tension. For practical purposes, it is developed to be efficiently and easily extensible to three-dimensional applications with a minor implementation complexity. The accuracy and convergence properties of the method are verified through a wide range of tests: advection of rigid interfaces of different shapes, a three-dimensional air bubble's rising in viscous liquids, a two-dimensional dam-break, and a three-dimensional dam-break over an obstacle mounted on the bottom of a tank. The standard advection tests show that the volume advection algorithm is comparable in accuracy with geometric interface reconstruction algorithms of higher accuracy than other interface capturing-based methods found in the literature. The numerical results for the remainder of tests show a good agreement with other numerical solutions or available experimental data. Copyright © 2009 John Wiley & Sons, Ltd. [source] A simple PWM method for improving lamp current crest factor of valley-filled electronic ballastINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 3 2010Zhi-Ren Lee Abstract In this paper, a PWM method to improve the lamp current crest factor (CCF) of the valley-filled electronic ballast (VFEB) is presented. The VFEB has merits of high power factor, simple structure, and low cost. However, it results in an excessive CCF, which will shorten the lifetime of low-pressure discharge lamp. The proposed method controls switching duty ratio by feeding forward the dc-link voltage waveform of VFEB. It decreased the duty ratio with rising of dc-link voltage. Therefore, the proposed method could restrain the lamp peak current and improve the lamp CCF. The control block diagram and basic theory are introduced to improve the CCF. The computer simulations verify the proposed method and derive a minimum lamp CCF. The experimental results demonstrate that the lamp CCF was reduced from 1.9 to 1.58, the ac line power factor is 96%, and the input current THD is 29.3%. The fixed switching frequency operation gains a satisfactory power quality. Copyright © 2008 John Wiley & Sons, Ltd. [source] Prevalence of renal cell carcinoma: A nation-wide survey in Japan, 2002INTERNATIONAL JOURNAL OF UROLOGY, Issue 6 2007Ken Marumo Objective: To investigate the incidence of renal cell carcinoma, classified by sex, age group and region in Japan, following a 5-year interval after a previous survey performed in 1997. Methods: The survey was conducted between the beginning of January 2002 and the end of December 2002. A total of 1288 institutions in all 47 prefectures throughout Japan were requested to register cases. Results: There were 7405 persons with renal cell carcinoma, consisting of 5063 males and 2342 females. Crude incidence rates were 8.2 and 3.6 per 100 000 population for men and women, respectively. Incidence rates in the Hokkaido region were highest followed by the Shikoku region. Conclusions: Despite incidence of renal cell carcinoma increasing to 7405 from the 6358 persons in 1997, statistical data reported by the Ministry of Health, Labor and Welfare indicate that rising age-adjusted death rate for this tumor reached a ceiling in the past decade. Early detection may have contributed to this current trend; however, further epidemiological research is required to fully elucidate this. [source] Cobalt requirement of beef cattle , feed intake and growth at different levels of cobalt supplyJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 3 2000F. J. Schwarz Summary In a study using a total of 36 German Simmental beef bulls weighing between 236 kg and about 620 kg the question of what constitutes an adequate Co supply was investigated with reference to the performance criteria growth, feed intake, energy intake, nutrient intake and carcass criteria. The bulls received a diet of corn silage ad libitum and 2.5 kg concentrate for a period of 280 days. Ten rations (R) with graduated Co supplements were fed with mean concentrations of 0.07 (R1), 0.09 (R2), 0.11 (R3), 0.15 (R4), 0.18 (R5), 0.26 (R6), 0.33 (R7), 0.42 (R8), 0.59 (R9) and 0.69 (R10) mg Co per kg dry matter (DM) intake. The Co supplement was added as CoSO47H2O. The diets with no or low Co supplementation produced either distinctly lower daily gains of 1045g (R1) and 1130g (R2) or lower daily gains of about 1260 g (R3, R4) than rations R5,R10, where daily gains averaged 1340 g. The mean daily feed intake per animal was also significantly or marginally affected with values of 6.0 kg DM (R1) rising to 7.7 kg DM (R2,R4) versus 7.9 kg DM on average (R5,R10). Calculations using the broken line model and the quadratic model show that the optimal Co supply for maximum growth is 0.12 mg/kg dietary DM and for maximum feed intake, 0.16,0.18 mg Co/kg dietary DM. After taking further biochemical criteria into account (Stangl et al. 2000), a level of 0.20 mg/kg dietary DM is recommended as an adequate Co supply for growing cattle. [source] Achieving hygiene in the domestic kitchen: the effectiveness of commonly used cleaning proceduresJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002T.A. Cogan Aims:,To quantify the transmission of Salmonella and Campylobacter to hands, cloths, and hand- and food-contact surfaces during the preparation of raw poultry in domestic kitchens, and to examine the impact on numbers of these bacteria of detergent-based cleaning alone, or in conjunction with thorough rising. Methods and Results:,Groups of volunteers prepared chickens for cooking. Surfaces were sampled either before cleaning or after cleaning using water and detergent with or without thorough rinsing. Although cleaning followed by rinsing consistently achieved decontamination of surfaces contaminated with Campylobacter, significant numbers of surfaces were still contaminated with low numbers of Salmonella. Where cloths contaminated with Salmonella were stored overnight, a reduction in the efficacy of detergent-based cleaning regimes was observed. Conclusions:,Rinsing is the critical step in ensuring that bacteria are removed from surfaces during cleaning, but this may still leave residual contamination. Growth of Salmonella occurs in some contaminated cloths during overnight storage; Salmonella on cloths stored overnight are also more difficult to remove by washing. Significance and Impact of the Study:,Rinsing, as part of the cleaning process, is a critical step in achieving hygiene in the kitchen. However, to achieve completely hygienic surfaces, the use of an antimicrobial agent may be necessary. [source] Measuring enthalpy of fast exothermal reaction with micro-reactor-based capillary calorimeterAICHE JOURNAL, Issue 4 2010K. Wang Abstract This work presents a new micro-reactor-based capillary calorimeter for the enthalpy measurement of fast exothermal reactions. The new calorimeter was operated in the continuous way and the reaction enthalpy can be easily measured with the online temperatures from detached sensor chips. A standard reaction system and an industrial reaction system were selected to test this new calorimeter with homogeneous and heterogeneous reaction processes. The measurement was taken place at nearly adiabatic situations and the reaction enthalpy was calculated from the rising of temperature. High accuracy and good repeatability were obtained from this new calorimeter with relative experimental errors less than 3.5% and 2.4%, respectively. The temperature response was quick in this new calorimeter too, which was benefit to the low cost of reactive component. The fast and accurate measurement was contributed to the nice mixing performance and strict plug flowing in the calorimeter. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Three metamorphic events recorded in a single garnet: Integrated phase modelling, in situ LA-ICPMS and SIMS geochronology from the Moine Supergroup, NW ScotlandJOURNAL OF METAMORPHIC GEOLOGY, Issue 3 2010K. A. CUTTS Abstract In situ LA-ICP-MS monazite geochronology from a garnet-bearing diatexite within the Moine Supergroup (Glenfinnan Group) NW Scotland records three temporally distinct metamorphic events within a single garnet porphyroblast. The initial growth of garnet occurred in the interval c. 825,780 Ma, as recorded by monazite inclusions located in the garnet core. Modelled P,T conditions based on the preserved garnet core composition indicate an initially comparatively high geothermal gradient regime and peak conditions of ,650 °C and 7 kbar. Monazite within a compositionally distinct second shell of garnet has an age of 724 ± 6 Ma. This is indistinguishable from a SIMS age of 725 ± 4 Ma obtained from metamorphic zircon in the sample, which is interpreted to record the timing of migmatization. This second stage of garnet growth occurred on a P,T path from ,6 kbar and 650 °C rising to ,9 kbar and 700 °C, with the peak conditions associated with partial melting. A third garnet zone which forms the rim contains monazite with an age of 464 ± 3 Ma. Monazite in the surrounding matrix has an age of 462 ± 2 Ma. This corresponds well with a U,Pb SIMS zircon age of 463 ± 4 Ma obtained from a deformed pegmatite that was emplaced during widespread folding and reworking of the migmatite fabric. The P,T conditions associated with the final phase of garnet growth were ,7 kbar and 650 °C. The monazite ages coupled with the phase relations modelled from this multistage garnet indicate that it records two Neoproterozoic tectonothermal events as well as the widespread Ordovician Grampian event associated with Caledonian orogenesis. Thus, this single garnet records much of the Neoproterozoic to Ordovician thermal history in NW Scotland, and highlights the long history of porphyroblast growth that can be revealed by in situ isotopic dating and associated P,T modelling. This approach has the potential to reveal much of the thermal architecture of Neoproterozoic events within the Moine Supergroup, despite intense Caledonian reworking, if suitable textural and mineralogical relationships can be indentified elsewhere. [source] Lipid peroxidation and vitamin E status in gestational diabetes mellitusJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2003Debjyoti Santra Abstract Aim: To investigate any correlation between plasma levels of lipid peroxides, antioxidant nutrient (,-tocopherol) and oxidized high-density lipoprotein (HDL) in patients with gestational diabetes and those with a normal pregnancy and the incidence of pre-eclampsia. Methods: Sixty pregnant women attending an antenatal clinic were recruited for the study and were divided into two groups. Thirty women with gestational diabetes mellitus were recruited in the study group. The glucose-tolerance-test criteria, using 100 g of glucose taken orally, as laid down by the American College of Obstetricians and Gynecologists (1994) for diagnosis of gestational diabetes mellitus was used. Thirty gestation-matched pregnant women with normal glucose tolerance test results were recruited as controls. A 10 mL venous blood sample was collected from each subject at the time of recruitment and thereafter at 4 week intervals until the time of delivery. Samples were analyzed for malondialdehyde thiobarbituric acid reactive, oxidized HDL-cholesterol and ,,tocopherol. The incidence of pre-eclampsia and its correlation with antioxidant and lipid peroxide levels were compared in both the groups. Results: Ten subjects out of 30 in the study group and three subjects out of 30 in the control group developed pre-eclampsia. The incidence of preterm labor in both the groups was same (16.66%). The mean lipid peroxide level was lower in the study group at recruitment and later the levels kept falling, whereas levels of ,,tocopherol and oxidized-HDL were higher in the study group and kept on rising at follow up. Conclusion: Gestational diabetes is not associated with increased levels of lipid peroxides and decreased levels of ,-tocopherol. [source] | |||||||||||||||||||||||||||||||||||||