Volume Change

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Comparison of intradialytic plasma volume change between online hemodiafiltration and standard hemodialysis

Comparison of intradialytic plasma volume change between online hemodiafiltration and standard hemodialysis

Hemodialysis is a renal replacement therapy for end-stage renal disease [1]. As an outpatient-based treatment, main- tenance hemodialysis is performed intermittently (2 – 3 sessions per week) and for short duration (3 – 5 h) per ses- sion. The intermittent treatment inevitably leads to fluid accumulation between sessions, which needs to be removed by ultrafiltration during each session [2]. The re- moval induces intradialytic plasma volume change (IPVC), which is a dominant cause of intradialytic hypotension (IDH); the reduction in systolic blood pressure was related to the reduction in IPVC, and an individual threshold of IPVC was noted for IDH [3 – 5].

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Density assumptions for converting geodetic glacier volume change to mass change

Density assumptions for converting geodetic glacier volume change to mass change

Besides the process of firn compaction that was explicitly modelled in this study, other effects can also influence the “density” of glacier volume change. Fischer (2011) describes the impact of opening and closure of crevasses on geode- tic volume change in detail. If many crevasses are present, the bulk density of the entire ice body decreases. Changes in crevasse frequency over time might lead to a bias in the con- version of volume to mass. The importance of this effect also depends on the timing (snow coverage) and the spatial res- olution of the geodetic survey. Although this process might affect f 1V , its magnitude is difficult to quantify and needs to

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Quantification of bone marrow lesion volume and volume change using semi automated segmentation: data from the osteoarthritis initiative

Quantification of bone marrow lesion volume and volume change using semi automated segmentation: data from the osteoarthritis initiative

Based on these findings, the new semi-automated BML segmentation method appears to be a valid assessment of BML volume, particularly BML volume change. There are several advantages of our method compared to existing methods. Firstly, this new approach can accurately measure volume rather than rough indices (e.g., greatest diame- ter [5], approximate BML volume [6,11]). In addition to improved accuracy, the semi-automated BML segmentation method offers good intra-rater reliability and adequate inter-rater reliability to allow for multiple raters if a quality assessment step is in place to ensure consistent bone segmentation. This extra quality assessment procedure is not uncommon in other areas of knee segmentation [27]. It is important to note that raters only mark the edges of the bone and therefore raters are not responsible for adjusting the contrast or identifying the boundary of a region that is not well delineated. The boundary of unclear BMLs would be located by the active contour driven by pixel intensity distribution automatically. Our approach should be more consistent than prior methods because it segments the BMLs from the bone region directly based on the intensity of the MR images without doing any preprocessing.

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Sensitivity of glacier volume change estimation to DEM void interpolation

Sensitivity of glacier volume change estimation to DEM void interpolation

While various methods are used in individual studies, the sensitivity of geodetic mass balance estimates to various in- terpolation methods is not clear. An overarching comparison of the numerous methods, and their subsequent effects on volume change estimates at both local and regional scales, is lacking. Using correlation values derived from photogram- metric processing of optical stereo imagery, we artificially introduce voids into a high-quality, spatially complete DEM and difference this DEM to another spatially complete DEM. We then apply 11 different methods to fill these artificially produced voids and compare the resulting estimates of vol- ume change both glacier by glacier and regionally to de- termine the potential impact on and sensitivity to volume change estimates. This study aims to quantify the effects of different void-handling approaches and to suggest the void- handling methods best suited for accurate volume change es- timation. As a final note, in this paper, we use two radar- derived DEMs: one derived from C-band radar and another derived from X- and P-band radar. Biases in the derived vol- ume change estimates exist due to differences in seasonal timing and radar penetration; as such, the estimates presented here should not be interpreted as mass balance estimates for these glaciers without additional corrections.

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Seismic moment and volume change of a spherical source

Seismic moment and volume change of a spherical source

Müller (2001) noted that the discrepancy between Equations 1 and 2 could not be resolved, and he inter- preted these two forms to correspond to the limits of the actual volume of the source. Wielandt (2003) discussed the discrepancy and noted that the source volume change depends on the source geometry. Richards and Kim (2005) argued that each relationship is based on a different defi- nition of volume changes at the source and that Equation 1 is preferred for characterizing underground explosions.

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Volume change pattern of decompression of mandibular odontogenic keratocyst

Volume change pattern of decompression of mandibular odontogenic keratocyst

The study group consisted of 17 patients, 8 males and 9 females, of average age 33.7 years (range 16–79 years). The average age of the 8 males was 29.8 years, and 9 fe- males was 37.2 years. OKC prevalence was highest in the second and third decade (9/17 patients). The average initial volume was 34,020.85mm 3 and after decompres- sion volume was 14,007.88 mm 3 . The average treatment period for all patients is 298 days of decompression (Table 1). The following formula presents the prediction of volume reduction according to elapsed time (Fig. 3). The volume of OKC undergoing decompression was re- duced by 25, 50, and 75% over 103, 270, and 727 days (Fig. 3).

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Mechanical Properties of Photovoltaic Silicon in Relation to Wafer Breakage.

Mechanical Properties of Photovoltaic Silicon in Relation to Wafer Breakage.

transformations in Si-phase can easily be identified by signature “pop-in” or “pop-out” events during micro- and nano-scale indentation testing [41, 54, 55, 59, 60]. Since occurrence of “pop-in” or “pop-out” involves subsurface cracking or sudden dislocation bursts [54, 61]. According to Bradby et al. [62] sequence of deformation events under penetrating indenter have been expressed in schematics (a) to (f) in Figure 2.9. The very small loads the nucleation of metallic Si-II is favored thermodynamically where local hydrostatic pressure reaches to ~12 GPa. The Si-II phase densifies Si-I structure with sudden 22 % reduction in the volume. The large volume of silicon in the direct contact with indenter, hence, during pressure-induced metallization deforms plastically and extrudes out along the indenter edge [63]. It has been identified as characteristic event of “pop-in” in the nanoindentation P-h plots. The plastic extrusion outside the diameter of constraint of the indenter boundary suggests semiconductor-to-metallic transition of lattice, which has been confirmed by simultaneous electrical conductivity measurements [62, 64, 65]. The extruded Si-II phase transforms to amorphous phase immediately due to sudden load relaxation. Pop-in has been associated with dislocation nucleation induced yielding due to large (~22%) volume change in silicon [61]. Hence, the stress-induced ductility in Si phase is the necessary to fundamentally understand the crack propagation and wafer slicing mechanism in photovoltaic (PV) silicon.

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Can the Earth's dynamo run on heat alone?

Can the Earth's dynamo run on heat alone?

to thermal contraction and, equivalently, volume change on freez- ing, do not enter the entropy balance and are therefore not avail- able to drive the dynamo. Furthermore, we show here that the pres- sure heating associated with volume change on freezing is equal to the additional latent heat released by the effect of the pressure change on the melting temperature and consequently the inner core radius. Mollett (1984) computed a more complete thermal history for the Earth using parametrized convection to account for mantle cooling and found that, for several choices of parameters, the inner core reached its present radius relatively early and then evolved much more slowly. More recent calculations by Buffett et al. (1996), Labrosse et al. (1997) and Stacey & Stacey (1999) all suggest the inner core is a rather recent feature, forming at about 2 Ga.

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The Model of Oceanic Crust Expansion

The Model of Oceanic Crust Expansion

According to the calculation of the earth’s volume change, during the forming stage of the earth (from 1.8 bil- lion years ago to the present), the state variation speed of the matters within the earth is 0.55 cubic kilometers per day. If the calculation is made according to the volume change coefficient of 0.097, the proportion of 83% that the oceanic crust expansion accounts for in the discharge of matters, the length of the expansion belt stret- ching for 15,000 km, the thickness of the oceanic crust being 10 km, the width of the oceanic crust expansion belt being 66 km, the cycle to form a group of oceanic crusts is approximately 750 thousand years, and the ex- pansion speed of oceanic crust is approximately 8.8 cm per year [1]. The expansion speed of the ocean crust ob- served in the modern era is approximate to 6 cm to 9 cm per year.

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Investigation on a Practical Model to Explain
      the Temperature Change of a Deflating Balloon

Investigation on a Practical Model to Explain the Temperature Change of a Deflating Balloon

More theoretical and experimental researches on natural and synthetic rubber were conducted in the middle of 20 th century, as the tire industry was boomed up. S. L. Dart and his colleagues observed the temperature changes with synthetics and natural rubbers. They plotted hysteresis curves of the changes on fast stretching of rubbers[1]. R. S. Stein modelled and verified the unusual pressure-volume relationships of inflating balloon. It has provided a fertile source of unconventional problems in physical chemistry and thermodynamics involving calculation of work, entropy changes, etc., applied to the volume change of a balloon[2]. F. Rodriguez suggested demonstrations whereby theoretical predictions can be illustrated either in a qualitative or a quantitative manner[3]. The demonstration includes considerations of uniaxial and biaxial stretching, as well as simple shear. D. R. Merritt, and F. Weinhaus derived an equation between the internal pressure and the radius of a rubber balloon. The theoretical pressure curve was shown to be experimentally verifiable in the case of low to moderate extensions, as long as the effects of hysteresis are ignored[4]. R. J. Farris provided an idealized mechanical and thermodynamic analysis of the rubber cycle and compared it to an equivalent cycle wherein a gas is the working fluid. His

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Deposits Funding and Loan Volatility in Iranian Banking System

Deposits Funding and Loan Volatility in Iranian Banking System

In this paper, we explored the uncertainty in the volumes of loans and relationship of this with deposit ratio. For this purpose, we analyzed the relationship between uncertainty and deposits by dynamic econometric model. This paper surveys the changes in uncertainty and the effects of this on the deposit funding. The results indicate the statistically significant negative relationship between bank volatility and structure of deposits. The effect of Loan GARCH on deposit ratio is negative and statistically significant. LOANSD and loan GARCH as loan volatility have negative effects on deposit ratio in the model. Change in loan has a positive and significant coefficient. Although increasing loan volatility leads to decrease deposit ratio, if there is a positive loan volume change, deposit ratio results in a positive volume change.

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Microcontroller based Intelligent Digital Volume Controller with Timer

Microcontroller based Intelligent Digital Volume Controller with Timer

Hardware – In this device, the timer thing is implemented in the software part and the volume change is being performed in the hardware. The implementation of a hardware clock attached to this device can make this thing work independently. In that clock, alarm time can be set by the user and the sound level will go down accordingly. The clock can act as an alarm clock too on implementing a separate buzzer with it. Further implementation of an IR remote with this device can make it more efficient and help the user to control the device from a distance. The volume level a user sets in the system gets reset, once the device is restarted. Implementing, a memory, i.e. an EEPROM with the device can solve the problem.

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Global glacier volume projections under high-end  climate change scenarios

Global glacier volume projections under high-end climate change scenarios

4.2 Regional glacier volume projections 2011–2097 Glaciated areas are divided into 18 regions defined by the RGI6 with no projections made for Antarctic glaciers be- cause the bias correction technique removes the HadGEM3- A data from this region. JULES is run for this century (2011 to 2097) using the best regional parameter sets for mass bal- ance found by the calibration procedure (Table 2). No ob- servations were available to determine the best parameters for Iceland and the Russian Arctic; therefore global mean parameter values are used for these regions. End of the cen- tury volume changes (in percent) are found by comparing the volume at the end of the run (2097) to the initial vol- ume calculated from the RGI6. Regional volume changes expressed in percent for low (0–2000 m), medium (2250– 4000 m), high (4250–9000 m), and all elevation ranges (0– 9000 m) are listed in Table 6. The total volume loss over all elevation ranges is also listed in millimetres of sea level equivalent in Table 6 and plotted in Fig. 10. Maps of the percentage volume change at the end of the century, rela- tive to the initial volume, are contained in the Supplement in Figs. S1–S7.

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Uterine Fibroid Embolization for symptomatic fibroids : study at a teaching hospital in Kenya

Uterine Fibroid Embolization for symptomatic fibroids : study at a teaching hospital in Kenya

Objective: Characterization of magnetic (MRI) features in women undergoing uterine fibroid embolization (UFE) and identification of clinical correlates in an African population. Materials and Methods: Patients with symptomatic fibroids who are selected to undergo UFE at the hospital formed the study population. The baseline MRI features, baseline symptom score, short-term imaging outcome, and mid-term symptom scores were analyzed for interval changes. Assessment of potential associations between short-term imaging features and mid-term symptom scores was also done. Results: UFE resulted in statistically significant reduction (P < 0.001) of dominant fibroid, uterine volumes, and reduction of symptom severity scores, which were 43.7%, 40.1%, and 37.8%, respectively. Also, 59% of respondents had more than 10 fibroids. The predominant location of the dominant fibroid was intramural. No statistically significant association was found between clinical and radiological outcome. Conclusion: The response of uterine fibroids to embolization in the African population is not different from the findings reported in other studies from the west. The presence of multiple and large fibroids in this study is consistent with the case mix described in other studies of African-American populations. Patient counseling should emphasize the independence of volume reduction and symptom improvement. Though volume changes are of relevance for the radiologist in understanding the evolution of the condition and identifying potential technical treatment failures, it should not be the main basis of evaluation of treatment success.

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Ch 5 Gases 95 slides .pptx

Ch 5 Gases 95 slides .pptx

The ideal gas law predicts that the volume of a gas at a constant T and P depends directly on the n. This makes sense in terms of the KMT because an increase in the n at the same temperature would cause the pressure to increase if the volume were held constant. The only way to return the pressure to its original value is to increase the volume.

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A Study on the “Flexibility” of Information Systems (Part 4): Theoretical Summary and the Validation with Examples

A Study on the “Flexibility” of Information Systems (Part 4): Theoretical Summary and the Validation with Examples

Over the past 50 years, IT managers have been struggling with this gap while seeking to resolve the issue. The literatures (Earl, 1993; Segars & Grover, 1999; Tallon et al., 2000; Jorfi et al., 2011) suggest that MIS flexibility could be one solution; however, few studies on practical approaches employ MIS flexibility planning to align IT and business strategy. Consequently, this paper focuses on the theme of IT/business strategy alignment to explore the solution to alleviate IT managers’ problems by means of solving the following question: How should we make our existing MIS flexible to absorb possible future demands for change?

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Relationship between consumer price index (CPI) and KSE 100 index trading volume in pakistan and finding the endogeneity in the involved data

Relationship between consumer price index (CPI) and KSE 100 index trading volume in pakistan and finding the endogeneity in the involved data

monthly data Chen, Roll and Ross (1986) found that inflation related variables w ere highly significant in the 1968-77 period and insignificant both earlier and later. Carlton (1983) reported that the inflation has a tremendous negative effect on volume traded. It appeared that the level of inflation, rather than the unanticipated comp onent of inflation, was more significantly correlated with volume traded. A related reason for a decline in trading as a result of increasing inflation has to do with the different types of the commodity that are deliverable on the futures market. Smirlock (1986) found a significant positive response of long -term rates to unexpected inflation. Smirlock (1986) reported that the unanticipated component of the announced change in both the PPI and the CPI has an immediate positive effect on long -term rates in the post-79 period, but no effect in the pre-79 period.

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Degrees of costs effectiveness

Degrees of costs effectiveness

Abstract: The article deals with the change of costs and its effect upon the change of profit in the monitored firm. The first part is devoted to the theoretical framework of the area. The formula needed for calculating indicators used are stated and described here and economic effects of the degrees of effectivness are explained by the means of graphs and formulas. The second part gives the definition of the degrees of effectiveness. Each of them is characterised by five items where monitored indicators are evaluated and described on the basis of observed data.

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The developing role of magnetic resonance imaging in Phase III multiple sclerosis treatment trials: Technical considerations and results of a large multicentre study

The developing role of magnetic resonance imaging in Phase III multiple sclerosis treatment trials: Technical considerations and results of a large multicentre study

The aim of this study was to determine sample size requirements for definitive MS treatment trials, based on an annual assessment of MRI brain lesion volume. Calculations were based on natural history and placebo data derived fi-om several centres, under the assumption that this cohort is representative of the behaviour of the placebo arm of a definitive phase III trial. There are several reasons to support this assumption. First, the clinical characteristics of the patients used in this study are consistent with those of patients who might be entered into a treatment trial. Second, the changes in lesion volume observed in this cohort at 12 months are of a similar magnitude to previously published data (Paty et al, 1993; Zhao et al, 1997; Stone et al, 1995b). Third, the variance estimates used in the power calculations include the multiple sources of 'noise' typical of such studies. The total between patient variance for the change in lesion volume observed in a sample is a composite of true biological differences between patients (sample heterogeneity) and the contribution of measurement error, as discussed in Chapter 4. Site by site differences in derived lesion volumes due to inter-scanner variation (Filippi et al, 1997a), differences in pulse sequence, slice thickness, and repositioning technique (Gawne-Cain et al, 1996; Simon et al, 1997; Filippi et al, 1997c) are ail likely to increase observed variance. The database for this study therefore reflects the multiple sources of variation due to measurement error that contribute to 'noise' in serial lesion volume assessment, as well as ‘true’ biological variance between patients.

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Response of cell volume in Mytilus gill to acute salinity change

Response of cell volume in Mytilus gill to acute salinity change

There are few other direct measurements of cell size in bivalves with which our optical and radiotracer measurements can be directly compared. The most extensive evidence for RVD is in red blood cells of the clam Noetia ponderosa, where cell volume (measured using a Coulter counter) rapidly returns to about 50 % of the control volume after an initial hypotonically induced swelling (Amende and Pierce, 1980). In contrast, data presented by Gainey (1994) for intracellular space in the posterior adductor muscle of several bivalve species (by comparing total water with extracellular space) indicate a variable response of cell volume to long-term salinity acclimation. Comparing intracellular water content with the relative osmotic concentration (see Table 3 in Gainey, 1994), cell volume regulation appears to be present in the posterior adductor muscle of Geukensia demissus. Cells in the posterior adductor muscle of Mytilus edulis, however, behaved as near-osmometers while the change in cell water space in Modiolus modiolus upon salinity acclimation was greater than that expected for a perfect osmometer. Comparisons of wet versus dry mass in various bivalves indicate that tissue water space follows a pattern suggestive of volume regulation, increasing after exposure to low salinity then returning towards control levels, and are cited as evidence of volume regulation in isolated tissues (Strange and Crowe, 1979; Deaton, 1990) and whole animals (Pierce, 1971; Gainey, 1978). However, changes in tissue water space may not accurately reflect the response of the intracellular water compartment alone (Gainey, 1994), since the change in total tissue water can also reflect a change in the size of the extracellular water compartment (Livingstone et al. 1979).

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