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The evaluation of hydrogen sorption properties in materials is crucial for their widespread applications. However, existing volumetric apparatuses often suffer from low accuracy and efficiency due to inadequate calibration techniques, temperature gradients, and limited automation. To address these limitations, a Temperature-Variable Cycle (TVC) Sieverts apparatus has been developed. Besides conventional tests, the device is capable of efficiently performing TVC tests, such as TVC Pressure-Composition-Temperature (PCT) isotherm and kinetics, through the integration of RS485 serial communication and automatic dosing techniques. The instrument's component selection and configuration were described in detail. Furthermore, novel methods for volume calibration and anti-thermal gradient were presented, where a continuous function was proposed to overcome temperature gradients across the entire range of test temperatures. Finally, a series of tests were conducted using La 0.5 Ce 0.5 Ni 4 Co alloy and Mg material as benchmark materials to validate the setup and methods. The accuracy of volumes and the feasibility of the methods were confirmed through null PCT tests and data comparisons of PCT with kinetic of La 0.5 Ce 0.5 Ni 4 Co alloy, respectively. By employing these methods, the accuracy of null tests is improved by nearly tenfold. The efficiency and robustness of the unit were demonstrated through Temperature-Programmed Desorption/Absorption (TPD/TPA), TVC PCT, and TVC kinetics tests on MgH 2 powder. The results produced by the TVC system align well with the reliable data in literature. [Display omitted] • An ultra-efficient and automatically TVC Sieverts apparatus has been developed. • The unit can obtain multiple curves at distinct temperatures within a single test. • A practical and accurate online volume calibration method was proposed. • A novel method of anti-thermal gradient for continuous temperature was presented. [ABSTRACT FROM AUTHOR]

In a Sieverts apparatus, the poor heat transfer performance of a sample cell leads to inaccuracy in kinetics test of hydrogen storage materials. Consequently, the analysis of heat transfer of the reaction process in the sample cell is essential. However, it is difficult for traditional detection methods to track the physical and chemical dynamic changes in the sample cell. In this paper, the finite element method was used to simulate the reaction process in the sample cell. A two-dimensional numerical model was designed to characterize the hydrogen absorption process in order to investigate the link between the heat transfer performance of the sample cell and the reaction kinetics. It was found that the reaction kinetics would be close to the intrinsic kinetics of the materials as its amount decreased. However, the decreased amount of hydrogen storage materials had a restricted effect on the increase of the reaction rate. The relevant amount of hydrogen storage material was recommended based on the comprehensive analysis of this study. In addition, the improvement of the thermal conductivity of the MH reaction bed and sample cell material improved the heat transfer performance to a certain extent. Finally, the relationship among the amount of hydrogen storage material, thermal conductivity and absorption time was established through the simulation analysis, which provided some schemes for optimizing the reaction kinetics testing accuracy of Sieverts apparatus. • The heat transfer performance of sample cell was simulated. • A numerical model describing the reaction process was developed. • The factors affecting the reaction kinetics were analyzed. • Some optimization schemes were proposed. [ABSTRACT FROM AUTHOR]

Objective A reliable, noninvasive method to differentiate high-grade glioma (HGG) and intracranial metastasis (IM) has remained elusive. The aim of this study was to differentiate between HGG and IM using tumoral and peritumoral diffusion tensor imaging characteristics. Methods A semiautomated script generated volumetric regions of interest (ROIs) for the tumor and a peritumoral shell at a predetermined voxel thickness. ROI differences in diffusion tensor imaging–related metrics between HGG and IM groups were estimated, including fractional anisotropy, mean diffusivity, total fiber tract counts, and tract density. Results The HGG group (n = 46) had a significantly higher tumor-to-brain volume ratio than the IM group (n = 35) (P < 0.001). The HGG group exhibited significantly higher mean fractional anisotropy and significantly lower mean diffusivity within peritumoral ROI than the IM group (P < 0.05). The HGG group exhibited significantly higher total tract count and higher tract density in tumoral and peritumoral ROIs than the IM group (P < 0.05). Tumoral tract count and peritumoral tract density were the most optimal metrics to differentiate the groups based on receiver operating characteristic curve analysis. Predictive analysis using receiver operating characteristic curve thresholds was performed on 13 additional participants. Compared with correct clinical diagnoses, the 2 thresholds exhibited equal specificities (66.7%), but the tumoral tract count (85.7%) seemed more sensitive in differentiating the 2 groups. Conclusions Tract count and tract density were significantly different in tumoral and peritumoral regions between HGG and IM. Differences in microenvironmental interactions between the tumor types may cause these tract differences. Highlights • Volumetric peritumoral FA was higher in gliomas than metastases. • Volumetric peritumoral mean diffusivity was lower in gliomas than metastases. • Intratumoral and peritumoral tract density was higher in gliomas than metastases. • Tract count–based predictive model successfully differentiated 10 of 13 subjects. • Tract density–based predictive model successfully differentiated 8 of 13 subjects. [ABSTRACT FROM AUTHOR]

Abstract: The volumetric performance of supercapacitors (SCs), besides the gravimetric performance, is attracting an increasing attention due to the fast development of electric vehicles and smart devices. Here, a unique design of symmetric supercapacitor material is reported with a tight face‐to‐face architecture by applying a high pressure to the delaminated Ti3C2 (d‐Ti3C2) films. The high pressure makes the d‐Ti3C2 films achieve an increased density, high electron conductivity, good wettability, and abundant interconnected mesopore channels to promote ion transport efficiently, that is, more cations can intercalate/deintercalate in the charging–discharging process. As a result, with the increase of the applying pressure, the d‐Ti3C2 film pressured at 40 MPa in 1 m Li2SO4 exhibits an ultrahigh capacitance of over 633 F cm−3, outstanding energy density, and cyclic stability. Especially, the corresponding SC in 1 m 1‐ethyl‐3‐methylimidazolium tetrafluoroborate/acetonitrile organic electrolyte shows a high volumetric energy density of 41 Wh L−1, which is the highest value reported for the SCs based on MXene materials in organic electrolytes. The outstanding volumetric electrochemical performance and thermal stability of the SCs based on the ultracompact d‐Ti3C2 film demonstrate their promising potential as forceful power sources for small electronic devices. [ABSTRACT FROM AUTHOR]

Summary: A new calorimetric facility for the aerothermal assessment of radiative‐convective heat exchangers in concentrating solar power applications has been developed and is described in this paper. The configuration of volumetric solar receivers enables concentrated sunlight to be absorbed and conducted within their solid volume, from where it is gradually transferred by forced convection to a heat transfer fluid flowing through their structure. Current design trends towards higher thermal conversion efficiencies have led to the use of complex intricate geometries to maximise temperatures deep inside the structure. The work presented aims to aid these objectives by commissioning a new experimental facility for the fully integrated evaluation of such components. The facility is composed of a high‐flux solar simulator that provides 1.2 kW of radiative power, a radiation homogeniser, inlet and outlet collector modules, and a working section that can accommodate volumetric receivers up to 80 mm × 80 mm in aperture. Irradiance levels and flow field nondimensional governing parameters are highly representative of on‐sun experiments at larger scales. Results from experiments with a siliconised silicon carbide monolithic honeycomb are presented, conducted at realistic conditions of incident radiative power per unit mass flow rate to validate its design point operation. Measurements conducted include absorber solid temperature distributions, air inlet and outlet temperatures, pressure drop, incident heat flux, and overall thermal efficiency. The relative influence of different sources of thermal loss is analysed and discussed. [ABSTRACT FROM AUTHOR]

This paper describes a volumetric solar receiver that is vertically integrated with beam-down optics for condensed light irradiation. The heat-transfer performance of a silicon carbide honeycomb receiver was investigated using a 30-kW th solar simulator and numerical simulation. The experiments achieved an air temperature of 840 K at the receiver outlet by varying the operational parameters. Numerical simulations were performed for a vertical honeycomb block with beam-down irradiation and a horizontal honeycomb block with tower-type irradiation to elucidate the effects of buoyancy. Three blocks with different sizes were simulated for a variety of operational parameters. When the block was oriented vertically, the flow and temperature fields remained nearly symmetric in and near the receiver. In contrast, when it was oriented horizontally, the flow and temperature became asymmetric, with the hot spot moving toward the receiver's side wall and the stream in the receiver being reversed. The vertical orientation's robustness to buoyancy effects prevented any reduction in the receiver efficiency or outlet temperature and suppressed the thermal leakage. [ABSTRACT FROM AUTHOR]

Development of carbon electrodes with high volumetric electrochemical performance is challenging for high-performance energy storage devices. In this work, we demonstrate a novel sucrose-derived porous carbon monolith (NPC-m) constructed by holey carbon nanosheets for super-high volumetric energy storages. NPC-m, derived from sucrose via a facile yet scalable and economic “bottom-up” synthesis route, exhibits a high specific surface area of 1376 m 2 g −1 , a narrow hole size distribution, and a high N content (∼6.65 at. %). Most importantly, a self-stacking density as high as 1.26 g cm −3 can be achieved via simple drying processes. The electrodes based on NPC-m in carbon electrodes deliver super-high volumetric capacities of 1385 mAh cm −3 (0.1 A g −1 ) for Li-ion batteries and 380 F cm −3 (0.5 A g −1 ) for supercapcacitors, highlighting their great potentials for high-performance energy storages. [ABSTRACT FROM AUTHOR]

Segmentation and volumetric quantification of white matter hyperintensities (WMHs) is essential in assessment and monitoring of the vascular burden in aging and Alzheimer’s disease (AD), especially when considering their effect on cognition. Manually segmenting WMHs in large cohorts is technically unfeasible due to time and accuracy concerns. Automated tools that can detect WMHs robustly and with high accuracy are needed. Here, we present and validate a fully automatic technique for segmentation and volumetric quantification of WMHs in aging and AD. The proposed technique combines intensity and location features frommultiplemagnetic resonance imaging contrasts and manually labeled training data with a linear classifier to perform fast and robust segmentations. It provides both a continuous subject specific WMH map reflecting different levels of tissue damage and binary segmentations. Themethodwas used to detectWMHs in 80 elderly/AD brains (ADC data set) as well as 40 healthy subjects at risk of AD (PREVENT-AD data set). Robustness across different scanners was validated using ten subjects from ADNI2/GO study. Voxel-wise and volumetric agreements were evaluated using Dice similarity index (SI) and intra-class correlation (ICC), yielding \mathrm ICC=0.96 , \mathrm SI= 0.62\pm 0.16 for ADC data set and \mathrm ICC=0.78 , \mathrm SI=0.51\pm 0.15 for PREVENT-AD data set. The proposed method was robust in the independent sample yielding \mathrm SI=0.64\pm 0.17 with \mathrm ICC=0.93 for ADNI2/GO subjects. The proposed method provides fast, accurate, and robust segmentations on previously unseen data from different models of scanners, making it ideal to study WMHs in large scale multi-site studies. [ABSTRACT FROM PUBLISHER]

The technology of gerotor pumps is progressing towards cutting-edge applications in emerging sectors, which are more demanding for pump performance. Moreover, recent environmental standards are heading towards leakage-free and noiseless hydraulic systems. Hence, in order to respond to these demands, this study, which will be referred to as the GeroMAG concept, aims to make a leap from the standard gerotor pump technology: a sealed, compact, non-shaft-driven gerotor pump with a magnetically-driving outer rotor. The GeroMAG pump is conceived as a variable-flow pump to accomplish a standard volumetric flow rate at low rotational speed with satisfactory volumetric efficiency. By following the authors' methodology based on a catalogue of best-practice rules, a custom trochoidal gear set is designed. Then, two main technological challenges are encountered: how to generate the rotational movement of the driving outer rotor and how to produce the guide of rotation of the gear set once there is no drive shaft. To confront them, a quiet magnet brushless motor powers the driving outer rotor through pole pieces placed in its external sideway and the rotational movement is guided by the inner edgewise pads carved on it. Subsequently, GeroMAG pump architecture, prototype, housing, methodology, materials and manufacture will be presented. As a principal conclusion, the GeroMAG proof of concept and pump prototype are feasible, which is corroborated by experimental results and performance indexes. [ABSTRACT FROM AUTHOR]

A new rotary volumetric pump, called a ‘Sliding-Vane Rotary Pump (SVRP)’, which was applied in the Xinjiang oilfield for its resistance to high temperature in well downhole was introduced in this paper. Compared to a conventional artificial lift pump, the volumetric efficiency and the energy saving are the obvious advantages of this pump. Based on the analysis of SVRP’s internal mechanical structure, the inner pressure distribution model of SVRP was established according to the compressibility of crude oil. Then, the load torque of both sides of the sliding-vane was calculated on the basis of the SVRP chamber pressure distribution model that has been established in the paper, and then the SVRP load torque curve was plotted. The pump load torque curve trend is consistent with the trend of the pressure curve. A conclusion was drawn that the ‘sealed angular difference’ of SVRP should be optimized to reduce the pump leakage and load torque for the reason of chamber pressure difference. The pressure variations of the pump chamber in the entire rotation period were analyzed in order to provide a theoretical pump leakage and pump efficiency analysis premise. It also can be utilized to explain the unbalanced pressure on pump bearing. [ABSTRACT FROM AUTHOR]

In this work, Zn(BH4)2, Ni, or Ti were selected as additives to improve the hydriding and dehydriding rates of magnesium. Zn(BH4)2 was prepared by milling ZnCl2 and NaBH4 in a planetary ball mill under an Ar atmosphere. The prepared Zn(BH4)2 sample contained NaCl. 13.6 wt.% MgH2+49.1 wt.% Zn(BH4)2+30.2 wt.% NaCl+7.0 wt.% Ni (named 14MgH2+49Zn(BH4)2+30NaCl+7Ni) and 13.6 wt.% MgH2+49.1 wt.% Zn(BH4)2+30.2 wt.% NaCl+7.0 wt.% Ti (named 14MgH2+49Zn(BH4)2+30NaCl+7Ti) samples were prepared by horizontal ball milling. The gas release properties, especially the metal hydride decomposition temperatures (the onset temperature of the metal hydride decomposition and the maximum rate of released gas quantity change with temperature change), of the prepared samples were investigated using a Sievert's type volumetric apparatus. The quantity of the gas released under 1.0 bar H2 was measured as the temperature was increased and the variation in the rate of released gas quantity Gr change with temperature T change, dGr/dT, as a function of temperature was obtained. This analysis method can be used instead of thermal analysis methods such as thermogravimetric analysis (TGA), differential scanning calorimeter (DSC), and differential thermal analysis (DTA). The investigated properties of the samples were then compared. In the as-milled 14MgH2+49Zn(BH4)2+30NaCl+7Ni, it is believed that Zn(BH4)2 begins to decompose at about 350 K and the rate of Gr change with T change, dGr/dT, reaches its peak at about 390 K, and that MgH2 begins to decompose at about 670 K and dGr/dT reaches its peak at about 698 K. [ABSTRACT FROM AUTHOR]

The problem of a body slipping down a frictionless hemisphere is very common in physics and engineering textbooks. In this type of problem, students are normally asked to find the angle at which the body flies off the surface. In this work, we have constructed an apparatus to determine the angle at which a ball flies off a circular track, and to study the motion of the ball (rolling and slipping) along the surface. The apparatus is comprised of two parallel rails that form a quarter circle. The angular position and velocity of a steel ball are measured using a moveable arm equipped with a photodetector. Two methods are used to determine the angle the ball loses contact with the track. Both methods provide values in agreement with a model for rolling followed by slipping. [ABSTRACT FROM AUTHOR]

In wireless sensor networks (WSNs), a space filling curve (SFC) refers to a path passing through all nodes in the network, with each node visited at least once. By enforcing a linear order of the sensor nodes through an SFC, many applications in WSNs concerning serial operations on both sensor nodes and sensor data can be performed, with examples including serial data fusion and path planning of mobile nodes. Although a few studies have made efforts to find such SFCs in WSNs, they primarily target 2D planar or 3D surface settings and cannot be directly applied to 3D volumetric WSNs due to considerably more complex geometric features and topology shapes that the 3D volumetric settings introduce. This article presents BLOW-UP, a distributed, scalable, and connectivity-based algorithm to construct an SFC for a 3D volumetric WSN (or alternatively to linearize the 3D volumetric network). The main idea of BLOW-UP is to decompose the given 3D volumetric network into a series of connected and closed layers, and the nodes are traversed layer by layer, incrementally from the innermost to the outermost, yielding an SFC covering the entire network, provably at least once and atmost a constant number of times. To the best of our knowledge, BLOW-UP is the first algorithm that realizes linearization in 3D volumetric WSNs. It does not require advance knowledge of location or distance information. It is also scalable with a nearly constant per-node storage cost and message cost. Extensive simulations under various networks demonstrate its effectiveness on nodes' covered times, coverage rate, and covering speed. [ABSTRACT FROM AUTHOR]

The effects of the addition of degassed water on bulk nanobubbles (ultrafine bubbles) of air in liquid water were investigated by measuring the volumetric concentration and size distribution at different dissolved air degree of saturation (DOS) values. The proportion of degassed water mixed with water containing bulk nanobubbles was increased to prepare samples having lower DOS values. It was found that the volumetric concentration of nanobubbles mostly decreased and the average nanobubble size became larger as the DOS was decreased. In our proposed mechanism, smaller nanobubbles are selectively dissolved into the surrounding liquid by Laplace pressure due to surface tension as the DOS is reduced. These results demonstrate that stable bulk nanobubbles are present even in water undersaturated with gas. The role of nanobubble under an ultrasound is also discussed. [ABSTRACT FROM AUTHOR]

Organic Rankine Cycle (ORC) power systems are nowadays an option for local and domestic cogeneration of heat and electric power. Very interesting are micropower systems for heat recovery from low potential (40–90 °C) waste and renewable heat sources. Designing an ORC system dedicated to heat recovery from such a source is very difficult. Most important problems are connected with the selection of a suitable expander. Volumetric machines, such as scroll and screw expanders, are adopted as turbine alternative in small-power ORC systems. However, these machines are complicated and expensive. Vane expanders on the other hand are simple and cheap. This paper presents a theoretical and experimental analysis of the operation of a micro-ORC rotary vane expander under variable heat source temperature conditions. The main objective of this research was therefore a comprehensive analysis of relation between the vane expander output power and the heat source temperature. A series of experiments was performed using the micropower ORC test-stand. Results of these experiments are presented here, together with a mathematical description of multivane expanders. The analysis presented in this paper indicates that the output power of multivane expanders depend on the heat source temperature, and that multivane expanders are cheap alternatives to other expanders proposed for micropower ORC systems. [ABSTRACT FROM AUTHOR]

This study examines the mass transfer characteristics of a rotating bed that is equipped with static baffles. The volumetric liquid-side mass transfer coefficient ( k L a ) and the effective gas–liquid interfacial area were determined using a deoxygenation system and a chemisorption of CO 2 in NaOH solution, respectively; the local liquid-side mass transfer coefficient ( k L ) was thus calculated. The effects of liquid flow rate, rotational speed, baffles and type of packing on these mass transfer parameters were investigated. Experimental results show that the bed with baffles had a higher interfacial area and lower k L than that without baffles. Adding baffles to the bed did not significantly affect the k L a values. Additionally, the packing with a larger specific interfacial area yielded higher values of k L a mainly because the effective interfacial area was higher. [ABSTRACT FROM AUTHOR]

The construction of a simple volumetric adsorption apparatus is highlighted. The setup is inexpensive and provides a clear demonstration of gas phase adsorption concepts. The topic is suitable for undergraduate chemistry and chemical engineering students. Moreover, this unit can also provide quantitative data that can be used by young researchers to screen the adsorption capacity of different adsorbent materials for various gases. A Labview-based interface was developed to allow the students to perform automated data acquisition and unit control. The laboratorial setup permits the simultaneous measurement of gas adsorption equilibrium on two adsorbent samples, up to 20 bar over a wide temperature range (303-1373 K). The quality of the obtained data was validated by comparison with adsorption isotherms recorded on a high-precision gravimetric apparatus. For this purpose, adsorption equilibria of carbon dioxide (CO2) at 303 and 353 K and nitrogen (N2) at 323 K were recorded on a commercial sample of metal-organic framework MIL-53(Al) as well as on activated carbon. The recorded data were in good agreement with the data obtained by gravimetry, which suggests the validity of the data produced using the new setup. [ABSTRACT FROM AUTHOR]

The objective of the present study was longitudinal evaluation of the volumetric tumor response and functional results after Gamma Knife radiosurgery of vestibular schwannomas, performed according to the modern standards of treatment. From October 2003 to September 2007, 133 consecutive patients with vestibular schwannomas were treated according to the concept of robotic Gamma Knife microradiosurgery, which is based on precise irradiation of the lesion, sparing adjacent structures, and delivery of the high radiation energy to the target. Multiple small-sized isocenters located within the border of the neoplasm were applied. The mean marginal dose was 11.5 Gy (range, 11-12 Gy). In total, 126 cases with a minimum posttreatment follow-up of 2 years (range, 2-7 years; median, 4 years) were analyzed. Temporary enlargement was noted in 25 % of tumors at 6 months after radiosurgery. At 3 years of follow-up, tumor shrinkage, stabilization, and increase in volume were marked in 73 %, 23 %, and 4 % of cases, respectively. All progressing lesions spontaneously stabilized later on and did not require additional management. In 3 % of patients, transitory impairment of the facial nerve function was marked; however, neither its permanent dysfunction nor trigeminal neuropathy attributed to radiosurgery was noted. Impairment of hearing compared to its pretreatment level was revealed in 4 %, 12 %, 13 %, and 16 % of patients at 6 months, 1 year, 2 years, and 3 years after radiosurgery, respectively, and this trend was statistically significant ( P = 0.0042). Overall, 77 % of patients with serviceable hearing before treatment preserved it 3 years thereafter. In conclusion, modern Gamma Knife radiosurgery provides effective and safe management of vestibular schwannomas. Nevertheless, possible temporary tumor enlargement, delay of its growth arrest, transient dysfunction of the cranial nerves, and gradual deterioration of hearing after irradiation should be always taken into consideration. [ABSTRACT FROM AUTHOR]

A syringe-based, electronic fluid dispenser is described. The device mechanically connects a syringe plunger to a linear slide potentiometer. As the syringe plunger moves, the electrical resistance between terminals of the potentiometer varies. Application and subsequent measurement of a DC voltage between the potentiometer pins is used to track the syringe plunger position and meter the volume dispensed. The syringe's plunger is actuated manually by the device's user. The dispensing device offers volumetric accuracy of better than 1% when the dispensed volumes were >10 mL. The device has been used for a traditional acid--base titration experiment and produced quantitative results indistinguishable from the conventional approach using a buret. The device is inexpensive, easy for students to understand, and simple to construct. [ABSTRACT FROM AUTHOR]

Abstract: Transverse maxillary deficiency is commonly found in patients with sleep apnea and is also related to abnormal breathing patterns. Maxillary expansion procedures promote widening of the nasal floor and reduce the resistance to airflow, and have a positive influence on nasopharynx function. In order to evaluate volume changes in the upper airway, 15 adult patients with transverse maxillary deficiency underwent surgically assisted rapid maxillary expansion (RME) until a slight overcorrection of the crossbite was obtained. Cone beam computed tomography (CBCT) volumetric images were obtained at three predefined time points. The mean age of the patients was 30.2 (±7.4) years; nine were females and six were males. The area, volume, and the smallest transverse section area of the airway were assessed using Dolphin Imaging 3D software. Statistical comparisons were made of the changes between time periods. No statistically significant differences were found for volume or area. However a significant difference was found between the preoperative and immediate postoperative smallest transverse section area (P <0.05). Maxillary expansion, as an isolated procedure, does not result in a statistically significant improvement in the airway dimensions and results in an inferior relocation of the smallest transverse section area. [Copyright &y& Elsevier]

Adsorption isotherms of pure methaneand nitrogen and their binarymixtures on Zeochem Co. zeolite 5A were measured using a static volumetricapparatus. Pure isotherms were measured at (273, 283, 303, 323, and343) K and pressures up to 10 bar, while binary data were measuredat (303 and 323) K and different pressures and bulk gas phase compositions.Experimentally measured data were validated using the integral thermodynamicconsistency test. In contrast to the aforementioned binary measurements,predictions of different thermodynamic models utilizing pure adsorptionisotherms were used to describe binary adsorption behavior of methaneand nitrogen over zeolite 5A. Models based on the thermodynamic theoryof solutions such as ideal adsorbed solution theory, vacancy solutionmodels, and two-dimensional equations of state were used for thispurpose. Experimental and predicted equilibrium data were comparedthrough the appropriate phase diagrams. Predicted selectivity curveswere compared against experimental data. All the proposed models arecapable to describe adsorption equilibria of the investigated system.Results of the present study show that methane and nitrogen form anideal and energetically homogeneous adsorptive system on Zeochem Co.zeolite 5A. [ABSTRACT FROM AUTHOR]

The responsible mechanism for the formation of the enhanced-V infrared cloud-top feature observed above tropopause-penetrating thunderstorms is not well understood. A new method for the combination of volumetric radar reflectivity from individual radars into three-dimensional composites with high vertical resolution (1 km) is introduced and used to test various formation mechanisms proposed in the literature. For analysis, a set of 89 enhanced-V storms over the eastern continental United States are identified in the 10-yr period from 2001 to 2010 using geostationary satellite data. The background atmospheric state from each storm is determined using the Interim ECMWF Re-Analysis (ERA-Interim) and radiosonde observations. In conjunction with the infrared temperature fields, analysis of the radar data in a coordinate relative to the location of the overshooting convective top and in altitudes relative to the tropopause suggests that above-anvil (stratospheric) cirrus clouds are the most likely mechanism for the formation of the enhanced V. [ABSTRACT FROM AUTHOR]

Background context: Adolescent idiopathic scoliosis (AIS) is a three-dimensional spinal deformation that affects adolescents, especially girls. The etiopathogenesis of this disease remains uncertain, and studies have been carried out to understand its cause and related organs. Previous studies suggest that AIS is probably related to the cerebellum dysfunction, which could also be related to the abnormality in morphology of the cerebellum. Purpose: The purpose of the study is to investigate the relationship between AIS and the volume and morphology of cerebellum. Study design/setting: The study design of the cerebellum segmentation and volume quantification involved the following four steps: whole-brain normalization, cerebellum isolation, mapping with the statistical cerebellum template, and cerebellum regional volume correction. Patient sample: In particular, high-resolution T1-weighted magnetic resonance images of 50 AIS patients with the right-thoracic curves (ie, Cobb angle ≥20°) and 40 age-matched normal controls were acquired. The exclusion criteria included history of head injury, back injury, severe headache, weakness or numbness in any limbs, urinary incontinence, nocturnal enuresis, and any space-occupying lesion found on magnetic resonance (MR) images. Outcome measures: The AIS subjects were all with moderate-to-severe curves (ie, Cobb angle ≥20°) (9 moderate and 41 severe; mean Cobb angle 48.7°, range 20°–90°). Methods: The cerebellum was parcellated to 28 regions by mapping with a well-recognized probabilistic MR cerebellum atlas. Student t test of each cerebellar region and the correction for multiple comparisons were performed. Results: The volumes of four regions, namely right VIIIa, right VIIIb, left X, and right X, were significantly increased by approximately 7.43% to 8.25% in the AIS compared with the control group. Statistically, the results suggested that the cerebellar volume in AIS patients was larger compared with normal controls in the cerebellum regions of prepyramidal-prebiventer and intrabiventer fissures, intrabiventer and secondary fissures, and floccular-nodular (X)-posterolateral fissure to the inferior hemispheric margin. Conclusions: The functions of the affected regions involve motor control, somatosensory, working memory, language, and response to visual stimulation. We conclude that the volume difference could be compensatory consequences in the central nervous system because of the persistent effort in AIS patients to maintain the body balance given the asymmetric spine. [ABSTRACT FROM AUTHOR]

This paper presents a new approach for the voxelization of volumetric scene graphs. The algorithm generates slices of each primitive intended to be voxelized using an FPGA based pixel processor. The Blist representation is used for the volume scene tree which reduces storage requirement for each voxel to the log(H + 1) bits. The most important advantage of this voxelization algorithm is that any volume scene tree expression can be evaluated without using any computation or stack. Also the algorithm is not object specific, i.e. the same algorithm can be used for the voxelization of different types of objects (convex and concave objects, polygons, lines and surfaces). Keywords: Volume scene tree; Blist; Voxelization; z-Buffer

An algorithm for dynamic multileaf-collimator (dMLC) tracking of a target performing a known a priori, rigid-body motion during volumetric modulated arc therapy (VMAT), has been experimentally validated and applied to investigate the potential of the Agility (Elekta AB, Stockholm, Sweden) multileaf-collimator (MLC) for use in motion-compensated VMAT delivery. For five VMAT patients, dosimetric measurements were performed using the Delta4 radiation detector (ScandiDos, Uppsala, Sweden) and the accuracy of dMLC tracking was evaluated using a gamma-analysis, with threshold levels of 3% for dose and 3 mm for distance-to-agreement. For a motion trajectory with components in two orthogonal directions, the mean gamma-analysis pass rate without trackingwas found to be 58.0%, 59.0% and 60.9% andwas increased to 89.1%, 88.3% and 93.1% with MLC tracking, for time periods of motion of 4 s, 6 s and 10 s respectively. Simulations were performed to compare the efficiency of the Agility MLC with the MLCi MLC when used for motion-compensated VMAT delivery for the same treatment plans and motion trajectories. Delivery time increases from a static-tumour to dMLC-tracking VMAT delivery were observed in the range 0%-20% for the Agility, and 0%-57% with the MLCi, indicating that the increased leaf speed of the Agility MLC is beneficial for MLC tracking during lung radiotherapy [ABSTRACT FROM AUTHOR]

SUMMARY Chromium-based metal-organic framework (MOF), MIL-101(Cr), has emerged as a potential hydrogen storage material because of its high specific surface area, tuneable pore size, and unique structure. A large portion of voids generated in MOFs remain unutilized for hydrogen storage owing to weak interactions between the walls of MOFs and H2 molecules. The present study was aimed to reduce the unutilized voids in MIL-101 by incorporating microporous activated carbon (AC) into MIL-101 pores and thereby enhancing its volumetric hydrogen storage capacity. MIL-101 and its AC composites were synthesized under hydrothermal conditions by adding AC in different proportions in situ during the synthesis of MIL-101. The synthesized materials were characterized by various physico-chemical methods such as powder X-ray diffraction, thermogravimetric analysis (TGA), N2-adsorption/desorption isotherms measured at 77.4 K, and transmission electron microscopy (TEM). AC@MIL-101/A prepared by the incorporation of 0.63 wt% of AC into MIL-101 shows the highest hydrogen uptake of 10.1 wt% at 77.4 K and up to 6000 kPa hydrogen pressure. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Joint analysis of medical data collected from different imaging modalities has become a common clinical practice. Therefore, image fusion techniques, which provide an efficient way of combining and enhancing information, have drawn increasing attention from the medical community. In this paper, we propose a novel cross-scale fusion rule for multiscale-decomposition-based fusion of volumetric medical images taking into account both intrascale and interscale consistencies. An optimal set of coefficients from the multiscale representations of the source images is determined by effective exploitation of neighborhood information. An efficient color fusion scheme is also proposed. Experiments demonstrate that our fusion rule generates better results than existing rules. [ABSTRACT FROM PUBLISHER]

Abstract: Ceramic foam is a promising material for the absorber of volumetric solar air receiver in concentrated solar thermal power (CSP) plant. The transient behaviors of volumetric solar air receiver are crucial to the receiver’s controllability, and to some extent, the plant’s safety. This study numerically analyzes the transient behaviors of volumetric solar air receiver under various working conditions. A fully coupled transientmodel of the volumetric solar air receiver is developed in this paper. The pressure drop of the absorber, the interfacial heat transfer between the flowing fluid and solid, and the radiative heat transfer due to concentrated solar radiation absorption by ceramic foam and the radiation transport inside the media were included together in this transientmodel. In addition, the temperature fields of the fluid and solid phases were obtained by using the local thermal non-equilibrium model. A comparison of the computed results with experimental data shows that this coupled transient model can be used to predict the performance of volumetric solar air receiver. Based on this model, the transient behaviors of the solar air receiver under a sudden heat flux, a sudden loss of heat flux, and a step change of heat flux were studied. The results of this study are very helpful in designing and controlling volumetric solar air receivers. [Copyright &y& Elsevier]

Abstract: ZrCo1−x Ni x (x = 0, 0.1, 0.2 and 0.3) alloys were prepared and their hydrogen storage behavior were studied. ZrCo1−x Ni x alloys of compositions with x = 0, 0.1, 0.2 and 0.3 prepared by arc-melting method and characterized by X-ray diffraction analysis. XRD analysis showed that the alloys of composition with x = 0, 0.1, 0.2 and 0.3 forms cubic phase similar to ZrCo with traces of ZrCo2 phase. A trace amount of an additional phase similar to ZrNi was found for the alloy with composition x = 0.3. Hydrogen desorption pressure–composition–temperature (PCT) measurements were carried out using Sievert''s type volumetric apparatus and the hydrogen desorption pressure–composition isotherms (PCIs) were generated for all the alloys in the temperature range of 523–603 K. A single sloping plateau was observed for each isotherm and the plateau pressure was found to increase with increasing Ni content in ZrCo1−x Ni x alloys at the same experimental temperature. A van''t Hoff plot was constructed using plateau pressure data of each pressure–composition isotherm and the thermodynamic parameters were calculated for desorption of hydrogen in the ZrCo1−x Ni x –H2 systems. The enthalpy and entropy change for desorption of hydrogen were calculated. In addition, the hydrogen absorption–desorption cyclic life studies were performed on ZrCo1−x Ni x alloys at 583 K up to 50 cycles. It was observed that with increasing Ni content the durability against disproportionation of alloys increases. [Copyright &y& Elsevier]

Abstract: The methane adsorption properties of High Surface Activated Carbon (HSAC) samples were evaluated at room temperature (298K) and pressure up to 3.5MPa using a new optimized volumetric apparatus f-PcT (fast Pressure–concentration–Temperature) for accurate and reliable gas adsorption measurements. A comprehensive characterization of different activated carbon samples was carried out by means of helium picnometry for the skeletal density evaluation, by the Brunauer–Emmett–Teller (BET) method for the measurement of the surface area, by Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD) for topography and long-range order estimation, respectively. All the adsorption data were evaluated by Langmuir/Tóth isotherm model with a very high accuracy. Comparison with data available in the literature shows a good agreement in terms of maximum methane uptake on similar materials and an enhanced performance for the reversible adsorption at very low pressure. In fact, the probed HSAC samples show both higher methane storage values for pressure up to 1.5MPa and totally reversible methane uptake up to many cycles without any treatment in between. Furthermore, their adsorption properties are stable also after air exposure. These results represent the starting point for a real and efficient alternative method to the natural gas storage for static and/or automotive applications. [Copyright &y& Elsevier]

Abstract: A three-dimensional optical model for a pressurized volumetric receiver (PVR) is developed and corresponding solar radiation propagation process within the PVR is simulated by the Monte Carlo Ray Tracing (MCRT) method. In the computation, the complicated photon transmission process in the SiC porous absorber is simplified as the transmission process in the statistically homogeneous and isotropic turbid medium. Meanwhile, the non-uniform cylindrical coordinate grid is applied in the statistics of energy distribution, which could greatly reduce the number of cells in the computational grid and time compared with normal uniform grid. Based on the above model, the energy distribution in the irregular macro scale porous absorber is determined and then the effects of system parameters, including the incidence angle, the shape of absorber and the optical property of absorber, on the local heat flux of the absorber are investigated. The results show that, under the given operating condition, the radiation heat flux is mostly concentrated at the top area of the absorber and the maximum heat flux value is up to 2.73 × 109 W m−3, but it quickly decreases in the sideward locations. The incidence angle and a relative narrow shape of absorber are helpful to reduce the maximum heat flux in the absorber. Furthermore, as the ratio of absorption coefficient/extinction coefficient decreases, the absorbed radiation energy distribution is more uniform and the max heat flux in the absorber decreases greatly. [Copyright &y& Elsevier]

Abstract: This paper presents experimental investigations of a novel miniature reciprocating ball pump (RBP) as a potential infusion pump or drug delivery system. The objectives of this study are to validate the RBP''s operational principle and to evaluate its performance. In the tests, the basic functionality of the pump has been established at different pumping frequencies ranging from 1.667Hz (100rpm) to 4.167Hz (250rpm) against different pressure heads ranging from 0mmH2O and 100mmH2O. In addition, experimental results show that the RBP can deliver a higher flow rate with a volumetric efficiency of 120% as compared to a conventional single acting reciprocating pump running under the same operating conditions. [Copyright &y& Elsevier]

The hydrogen desorption/absorption behaviors of LiAlH4/LiBH4 with a focus on the effects of catalysts, namely TiCl3, TiO2, VCl3, and ZrCl4, were investigated using a thermal-volumetric apparatus. The hydrogen desorption was performed from room temperature to 300 °C with a heating rate of 2 °C min-1. The LiAlH4-LiBH4 mixture with a molar ratio of 2:1 decomposed between 100 and 220 °C, and the hydrogen desorption capacity reached up to 6.6 wt %. Doping 1 mol % of a catalyst to the mixture resulted in the two-step decomposition and a decrease in the hydrogen desorption temperature. All the doped samples provided lower amountz of desorbed hydrogen than that obtained from the undoped one. No hydrogen absorption was observed under 8.5 MPa of hydrogen pressure and 300 °C for 6 h. Despite the fact each of the catalysts may affect the hydrogen storage behaviors of the mixture differently, none resulted in a change in the sample reversibility [ABSTRACT FROM AUTHOR]

Abstract: This study presents a new model for analyzing the temperature distribution and weld pool shape in Nd:YAG pulsed laser welding. In the proposed approach, a surface flux heat transfer model is applied in the low laser energy intensity region of the weld, while a keyhole heat transfer model based on a volumetric heat source is applied in the high laser energy intensity region of the weld. The correlation between the intensity of the laser input energy and the geometric parameters of the volumetric heat source is derived experimentally. A series of MARC finite element simulations based on the proposed single pulse model are performed to investigate the shape and size of the weld pool given different laser energy intensities. A good agreement is observed between the simulation results and the experimental results obtained under equivalent single pulse welding conditions. Thus, the basic validity of the proposed model is confirmed. [Copyright &y& Elsevier]

Defects data and design optimization of gating system are a great challenge in casting. Most significant factors contributing to the volumetric changes and defects are pouring temperature, time, filling pattern, gating system, and casting geometry. The optimized design of gating system facilitates the smooth filling of the mold without air entrapment, material flow hindrance. Conventionally, the foundry method includes design calculations, best practices, and the tedious hit-and-trial method to get the optimum design of pattern/mold for defect-free casting. The design iterations and improvements directly affect the development cost and time, and one of the great challenges of the foundry method is to reduce this time and cost. The numerical simulation techniques embedded in casting simulation software are a powerful tool to overcome these challenges. It predicts the factors such as filling pressure, velocity, cooling rate, hot spots, and inside porosity. This article describes the design, simulation, experimental results, and design improvements for the complex geometries in the sand casting process. Impeller is selected as test case. The gating system was initially designed by using the text book mathematical relations and best practices recommendations. To study the predicted results of effected parameters, MAGMASOFT Software was used as a simulation tool. Three design modifications of mold design were studied. The effect of design including location and size of risers, gates on parameters such as filling pattern, pressure and velocity, cooling rate, solidification and defects such as air entrapment, hot spot, and porosity were studied. The predicted results were then compared with experimental data, and an excellent agreement between them was reported. The article highlighted the effectiveness of simulation to reach an optimal design of mold by passing the costly hit-and-trial conventional practice in the foundry industry and shows the effectiveness of simulations in time compression of casting pattern/development. [ABSTRACT FROM PUBLISHER]

This paper describes a unique, proof of the principle test facility and the results of a study carried out to provide experimental evidence needed to properly asses the techno-economic feasibility of heat integrated distillation column (HIDIC) utilizing structured internals to enhance both heat and mass transfer. The plate-packing configuration using structured packing exhibited a superior performance in comparison with the HIDIC based on the plate-fin heat exchanger. Experimental evidence shows that the mass transfer and heat transfer efficiency increase pronouncedly with increasing throughput, which however is accompanied by an increasing pressure drop per stage. Simulation of an industrial scale plate-packing unit revealed that an even better performance can be obtained by increasing the volumetric thermal load via further optimization of internals. [ABSTRACT FROM AUTHOR]

Two different perturbative approaches have been recently presented for the evaluation of scattering from layered media characterized by rough interfaces: the Boundary Perturbation Theory (BPT) and the Volumetric-Perturbative Reciprocal Theory (VPRT). These two approaches are conceptually different: They employ different strategies to provide closed-form solutions to the scattering problem, and, at first sight, they rely on different basic assumptions, so that different regimes of validity seem to be expected. In spite of that, both approaches lead to the same expression of the first-order scattered field. To solve this (seeming) incongruence, in this paper a careful theoretical analysis of basic assumptions of VPRT is carried out. This requires also considering the procedure to obtain the VPRT solution that, in this paper, is reformulated relying on a more physically sound way. The performed analysis demonstrates that, actually, basic assumptions of VPRT are equivalent to those of BPT, so that their ranges of validity are, consistently, also the same. Thus, the seeming incongruence is solved: The two theoretical constructs can be now regarded in a conceptually coherent frame. [ABSTRACT FROM AUTHOR]

A laboratory investigation was made of the effects of isotropic unloading on the mechanical behaviour of cemented sandstones, modelling in a simple way the influence of sampling on hydrocarbon reservoir sandstones that have been cemented at depth. Artificial samples of sandstone were created by allowing a cement to hydrate while a sand sample was under a high confining stress in a triaxial apparatus. Comparisons were then made between the behaviour of samples that had been unloaded to zero confining stress with that of samples tested at stress levels around that during cementing. It was found that the isotropic unloading damaged the cement, which had a significant effect on the small-strain and yielding behaviour but not on the strength and large-strain behaviour. Comparisons were also made with tests on natural samples of reservoir and analogue sandstones, and it was found that the artificial sandstone had reproduced the key elements of their behaviour. The intrinsic properties of all of the sandstones tested were found to be similar, although there were significant differences in the peak strengths and gross yielding envelopes. Cement content was found not to be the sole factor that influenced the peak and gross yield envelopes, and significant anisotropy was also revealed in one sandstone. [ABSTRACT FROM AUTHOR]

The article focuses on an observational finding of discrimination criteria between planar and volumetric faults through ultrasonic pulse-echo or phased array method grounded on the ratio of diffracted echoes in welding testing. It presents the confirmation whether the modulation value modeled by the method is consistent with the examinations through fracture mechanics criteria. It also shows if the element condition can be examined applying the applicable criteria for the type of defects.

Abstract: Objectives: To test the accuracy of measurements of tooth wear using a non-contacting laser profilometer (NCLP) and surface matching software. Methods: The accuracy and repeatability of the NCLP and software in measuring length was assessed by repeatedly scanning a calibrated 25mm engineering steel gage block. Volumetric measurements were assessed after scanning commercially pure titanium frustums of varying volume. The accuracy and repeatability of the systems in measuring step height and volume after surface matching were assessed using a custom built model with cemented engineering slip gages and cemented onlays of super-plastically formed titanium. The overall effect on the uncertainty of measurement of repeated superimpositions of the same cast, repeated impressions of the same patient and using step-over distances smaller than the laser spot size were also quantified. Results: The accuracy and repeatability were 1.3μm and 1.6μm in measuring length. The system was accurate for volumetric measurement with coefficients of variation <5%. Measurements using the model with cemented engineering slip gages and cemented super-plastically formed titanium onlays varied slightly (23.07μm and 1.6mm3). Scanning and superimposing the same model introduced mean error of 2.7μm (SD=0.7). Scanning and superimposing separate casts from repeated impressions of a patient introduced mean error of 14.8μm (SD=2.8). Decreasing step-over distances reduced measurement error (p <0.05). Significance: The methodologies described here served to assess sources of error in tribology studies using surface mapping and surface matching technologies. The results optimized data interpretation. Study supported by Guy''s and St. Thomas’ Charity and the Royal College of Surgeons of England. [Copyright &y& Elsevier]

A rapid, reliable radiation-free method of pediatric body venography might complement US by evaluating veins in the abdomen and pelvis and by providing a global depiction of venous anatomy. We describe a MR venography technique utilizing gadofosveset, a blood pool contrast agent, in children. The technique allows high-spatial-resolution imaging of the veins from the diaphragm to the knees in less than 15 min of total exam time. [ABSTRACT FROM AUTHOR]

Abstract: Improvements in solar-to-thermal energy conversion will accelerate the development of efficient concentrated solar power systems. Nanofluid volumetric receivers, where nanoparticles in a liquid medium directly absorb solar radiation, promise increased performance over surface receivers by minimizing temperature differences between the absorber and the fluid, which consequently reduces emissive losses. We present a combined modeling and experimental study to optimize the efficiency of liquid-based solar receivers seeded with carbon-coated absorbing nanoparticles. A one-dimensional transient heat transfer model was developed to investigate the effect of solar concentration, nanofluid height, and optical thickness on receiver performance. Simultaneously, we experimentally investigated a cylindrical nanofluid volumetric receiver, and showed good agreement with the model for varying optical thicknesses of the nanofluid. Based on the model, the efficiency of nanofluid volumetric receivers increases with increasing solar concentration and nanofluid height. Receiver-side efficiencies are predicted to exceed 35% when nanofluid volumetric receivers are coupled to a power cycle and optimized with respect to the optical thickness and solar exposure time. This work provides insights as to how nanofluids can be best utilized as volumetric receivers in solar applications, such as receivers with integrated storage for beam-down CSP and future high concentration solar thermal energy conversion systems. [Copyright &y& Elsevier]

Abstract: This paper proposes a volumetric gas meter, on-line, based on the liquid displacement principle. The proposed measuring device is the capacity to measure volumetric gas in a range from 1mL to 1000mL, from a laboratory-scale biogas reactor. As application, the meter is used in order to obtain the biogas production data file of a laboratory-scale Upflow Anaerobic Sludge Blanket (UASB) reactor. [Copyright &y& Elsevier]

The article discusses research on the use of a volumetric velocimetry imaging system to gather information on fish locomotion. The swimming behaviours of four bluegill sunfishes and one cichlid were observed, particle position and displacements were also determined. Dorsal fin wake properties were noted to be highly variable while anal fins produced a consistent jet angle. Volumetric imaging of flow patterns is considered an effective technique for the study of locomotor dynamics.

Modified kaolin clays were used as adsorbents for SO2 gas adsorptions. The clays were heated up to 900 °C previous to acid treatments with 0.5 N sulfuric acid solutions at boiling temperature during different times up to 1440 min. Equilibrium adsorption at 25 °C and 0.1 MPa was carried out by using a volumetric apparatus. The samples were characterized by chemical analysis, X-ray diffraction and infrared analysis. The heating of the clays followed by acid treatment improved the adsorption capacity of the kaolin clays. The presence of amorphous silica and hydroxyl in the final products improved SO2 adsorption capacity. Better properties for SO2 adsorption were found in kaolin rich in not well ordered kaolinite clay mineral. [Copyright &y& Elsevier]

Purpose: Elekta accelerators controlled by the current clinically used accelerator control system, Desktop 7.01 (D7), uses binned variable dose rate (BVDR) for volumetric modulated arc therapy (VMAT). The next version of the treatment control system (Integrity™) supports continuously variable dose rate (CVDR) as well as BVDR. Using CVDR opposed to BVDR for VMAT has the potential of reducing the treatment time but may lead to lower dosimetric accuracy due to faster moving accelerator parts. Using D7 and a test version of Integrity, differences in ability to control the accelerator, treatment efficiency, and dosimetric accuracy between the two systems were investigated. Methods: Single parameter tests were designed to expose differences in the way the two systems control the movements of the accelerator. In these tests, either the jaws, multi leaf collimators (MLCs), or gantry moved at constant speed while the dose rate was changed in discrete steps. The positional errors of the moving component and dose rate were recorded using the control systems with a sampling frequency of 4 Hz. The clinical applicability of Integrity was tested using 15 clinically used VMAT plans (5 prostate, 5 H&N, and 5 lung) generated by the SmartArc algorithm in PINNACLE. The treatment time was measured from beam-on to beam-off and the accuracy of the dose delivery was assessed by comparing DELTA4 measurements and PINNACLE calculated doses using gamma evaluation. Results: The single parameter tests showed that Integrity had an improved feedback between gantry motion and dose rate at the slight expense of MLC control compared to D7. The single parameter test did not reveal any significant differences in the control of either jaws or backup jaws between the two systems. These differences in gantry and MLC control together with the use of CVDR gives a smoother Integrity VMAT delivery compared to D7 with less abrupt changes in accelerator motion. Gamma evaluation (2% of 2 Gy and 2 mm) of the calculated doses and DELTA4 measured doses corrected for systematic errors showed an average pass rate of more than 97.8% for both D7, Integrity BVDR, and Integrity CVDR deliveries. Direct comparisons between the measured doses using strict gamma criteria of 0.5% and 0.5 mm showed excellent agreement between D7 and Integrity delivered doses with average pass rates above 95.7%. Finally, the Integrity control system resulted in a significant 35% (55 ± 13 s) reduction in treatment time, on average. Conclusions: Single parameter tests showed that the two control systems differed in their feedback loops between MLC, gantry, and dose rate. These differences made the VMAT deliveries more smooth using the new Integrity treatment control system, compared to the current Desktop 7.01. Together with the use of CVDR, which results in less abrupt changes in dose rate, this further increases the smoothness of the delivery. The use of CVDR for VMAT with the Integrity desktop results in a significant reduction in treatment time compared to BVDR with an average reduction of 35%. This decrease in delivery time was achieved without compromising the dosimetric accuracy. [ABSTRACT FROM AUTHOR]

BACKGROUND: It is unknown whether the use of volumetric infusion pumps for the transfusion of red blood cells (RBCs) or platelet (PLT) concentrates (PCs) affects the quality of the blood components. We therefore investigated the in vitro quality of these components after use of infusion pumps. STUDY DESIGN AND METHODS: Ten different volumetric infusion pumps were used to simulate transfusion with RBCs and PCs. To prevent donor-dependent differences multiple units were pooled and divided into equal portions. The storage time of RBCs was 30 to 35 days (n = 10 experiments), and for PCs, either 2 (n = 5) or 7 days (n = 5). For RBCs an infusion rate of 100 or 300 mL/hr was used, and for PCs, 600 mL/hr. Transfusions without an infusion pump served as a reference. RESULTS: None of the infusion pumps induced an increase of free hemoglobin, annexin A5 binding, or formation of echinocytes in RBCs compared to reference units. In 2- and 7-day-old PCs no effect was shown on PLT concentration, annexin A5 binding, mean PLT volume, and morphology score compared to the reference. The CD62P expression of 2-day-old PCs was significantly lower after transfusion compared to the reference, that is, 11.7 ± 2.1% versus 8.1 ± 1.3% (p < 0.01). CONCLUSION: There was no adverse effect on the in vitro quality of RBCs or PCs after simulated transfusion using volumetric infusion pumps. A decrease in PLT activation was observed, which can probably be explained by capturing of activated or damaged PLTs in the 200-µm filter present in the infusion system. [ABSTRACT FROM AUTHOR]

The paper deals with constructive solutions for an equipment dedicated to ultrasonic aiding of wire electrodischarge machining (WEDM+US). Basic phenomenology is presented emphasising the contribution of ultrasonics within removal mechanism at WEDM. Finite element method is applied to simulate WEDM+US removal process obtaining results in agreement with preliminary experimental data. The use of equipment at volumetric EDM is also presented in a variant of lateral flushing. Costs analysis is accomplished in order to establish the rentability of WEDM+US. [ABSTRACT FROM AUTHOR]