Mass Output Research Articles

Effects of particle sizes and physical form of the diet on performance, egg quality and size of the digestive organs in laying hens

Summary The influence of feed form (mash, crumble and pellet) and screen size (5 mm and 8 mm) on laying performance, egg quality, digestive organ measurements and gizzard pH was examined in laying hens using a 3 × 2 factorial arrangement of treatments. Lohmann LSL-Classic white egg layers (n = 864) at 28 weeks of age were randomly divided into 6 dietary treatments, each with 6 replicates of 24 birds over the following 24 weeks period. Significant ( P < 0.05) interactions between feed form and screen size were observed for egg mass output. Grinding ingredients through a screen size of 5 mm instead of 8 mm, as well as further processing of the feed mixture as mash and crumble increased egg mass, whereas a contrasting pattern was observed in the case of feeding on pellets. Egg production rate, egg weight, and cracked-broken egg rate were not affected by either particle size or form of the feed. Administering the diet in the form of pellet and crumble decreased feed intake of hens compared to mash ( P < 0.01). The feed conversion ratio of hens fed on crumbled and pelleted diets was significantly lower ( P < 0.01) than for those receiving a mash diet ( P < 0.01). Egg quality characteristics were barely affected by either screen size or feed form. However, the consumption of feed in the crumbled and pelleted forms decreased the yolk colour score by 4% ( P < 0.05). Screen size and feed form had no effects on the percentage weight of liver, gizzard, length of small intestine and gizzard pH. However, lowering screen size from 8 to 5 mm increased pancreas weight ( P < 0.01). The overall results of this experiment suggest that feed form (mash vs. crumbles or pellets) had a greater effect on the FI and FCR of laying hens than dietary ingredient particle size, with the best efficiency of feed conversion being obtained from pellet-fed birds. The effect of particle size was pronounced for eggshell mineralisation and pancreatic functions.

Constraints on rainbow gravity functions from black-hole thermodynamics

In this paper, we investigate the thermodynamic properties of black holes in the framework of rainbow gravity. By considering rainbow functions in the metric of Schwarzschild and Reissner-Nordström black holes, remnant and critical masses are found to exist. Demanding the universality of logarithmic corrections to the semi-classical area law for the entropy leads to constraining the form of the rainbow functions. The mass output and the radiation rate for these constrained form of rainbow functions have been computed for different values of the rainbow parameter η and have striking similarity to those derived from the generalized uncertainty principle.

THE STUDY OF HYDRODYNAMIC PROCESSES AT THE GAS FLOW FILTRATION THROUGH THE CANDIED FRUITS LAYER

The experimental studies of hydrodynamics of the gas flow filtration through the candied fruits layer, formed by the different methods, were carried out. The particles of studied candied fruits were cylindrical, equally sized, filled the whole container for drying. The main characteristics of the layers were experimentally determined: porosity, equivalent diameter, specific surface. The results of experiments prove the expedience of the candied fruits layer formation of the cylindrical particles with correct form by the method of placing candied fruits vertically “with overlap of channels”. Such method allows provide the insignificant hydraulic resistance of the layer and rather high speed of the gas flow filtration through this layer. It will result in the increase of heat transfer and mass output coefficients, so to the intensification of filtration drying. Such formation method also allows reduce the volume of drying equipment, shorten the time of drying and decrease the energy consumption of process.

Reconstitution of the complete rupture in musculotendinous junction using skeletal muscle-derived multipotent stem cell sheet-pellets as a “bio-bond”

Background. Significant and/or complete rupture in the musculotendinous junction (MTJ) is a challenging lesion to treat because of the lack of reliable suture methods. Skeletal muscle-derived multipotent stem cell (Sk-MSC) sheet-pellets, which are able to reconstitute peripheral nerve and muscular/vascular tissues with robust connective tissue networks, have been applied as a “bio-bond”.Methods. Sk-MSC sheet-pellets, derived from GFP transgenic-mice after 7 days of expansion culture, were detached with EDTA to maintain cell–cell connections. A completely ruptured MTJ model was prepared in the right tibialis anterior (TA) of the recipient mice, and was covered with sheet-pellets. The left side was preserved as a contralateral control. The control group received the same amount of the cell-free medium. The sheet-pellet transplantation (SP) group was further divided into two groups; as the short term (4–8 weeks) and long term (14–18 weeks) recovery group. At each time point after transplantation, tetanic tension output was measured through the electrical stimulation of the sciatic nerve. The behavior of engrafted GFP+ tissues and cells was analyzed by fluorescence immunohistochemistry.Results. The SP short term recovery group showed average 64% recovery of muscle mass, and 36% recovery of tetanic tension output relative to the contralateral side. Then, the SP long term recovery group showed increased recovery of average muscle mass (77%) and tetanic tension output (49%). However, the control group showed no recovery of continuity between muscle and tendon, and demonstrated increased muscle atrophy, with coalescence to the tibia during 4–8 weeks after operation. Histological evidence also supported the above functional recovery of SP group. Engrafted Sk-MSCs primarily formed the connective tissues and muscle fibers, including nerve-vascular networks, and bridged the ruptured tendon–muscle fiber units, with differentiation into skeletal muscle cells, Schwann cells, vascular smooth muscle, and endothelial cells.Discussion. This bridging capacity between tendon and muscle fibers of the Sk-MSC sheet-pellet, as a “bio-bond,” represents a possible treatment for various MTJ ruptures following surgery.

Dynamic characteristics and enhanced performance of a novel wind turbine rotor analyzed via experiments and numerical simulation

The enormous demand for large wind turbine rotors has led to a need to develop high-performance and reliable wind turbine rotors. The flexibility of the huge blade was a challenge in creating a balanced design with regard to dynamic behavior, mass, and power output. To enhance the wind turbine rotor, a newly designed wind turbine system with a supporting rod and damper was proposed and investigated. A scaled blade was experimentally tested, with the results indicating an increase in both frequency and damping of the system. Through the use of a self-coded numerical model, the correlations between the design constraints and the dynamic behavior, tip displacement, and additional mass of the rotor were demonstrated. This showed that the novel rotor has some preferable characteristics in both static and dynamic aspects. In particular, this blade is stiffer and has a smaller tip displacement compared with a traditional cantilevered blade. These characteristics enabled the effective application of the novel rotor to a 5-MW wind turbine to achieve a 15.16% power output increase based on the blade element momentum theory with Prandtl correction, as well as 5.1% mass savings. Copyright © 2016 John Wiley & Sons, Ltd.

Determination of the Nip Angle in Roller Compactors With Serrated Rolls

In roller compaction, the nip angle defines the critical transition interface between the slip and nip regions which is used to model material densification behavior and the properties of compacted ribbons. Current methods to determine the nip angle require either sophisticated instrumentation on smooth rolls or input parameters that are difficult to obtain experimentally. In this study, a practical method to determine nip angles for serrated rolls was developed based on mass balance considerations established around the nip region. Experimental input relating to roll geometry, powder density, and mass output from the compactor were required and they could be obtained reliably. The calculated nip angles were validated against those obtained from physical measurements during actual roll compaction. These nip angles were in agreement for various powder formulations containing plastic and brittle materials. The nip angles ranged from 4° to 12° and decreased significantly when the proportion of brittle material increased. Nip angles were also calculated using the widely used Johanson model. However, wall friction measurement on serrated roll surfaces could be impractical. The Johanson model-derived nip angles could differ by 3°-8° just by altering the roughness of the reference wall and this had compromised their reliability.

Analysis of process parameters related to the single-screw extrusion of recycled polypropylene blends by using design of experiments

The process dynamics of single-screw extrusion on mixtures of polypropylene (PP) and recycled PP were studied using a statistical, design of experiments (DoE) approach. For a conventional screw design, the barrel temperature, screw speed and two vastly different melt viscosity polypropylene mixtures were selected as the independent factors, whilst melt pressure, mass output, screw torque and temperature rise at the die due to shear heating were the dependent responses. A central composite design (CCD) in the framework of response surface methodology (RSM) was constructed, and an analysis of variance (ANOVA) was carried out to determine the significance of the response surface models. The resulting statistical and response surface predictions have demonstrated that the low viscosity component concentration in the blend is a dominating factor on melt pressure and screw torque, apart from the expected effect of screw speed on output. Viscous heating is affected only by screw speed and recycled polypropylene concentration. Furthermore, the predictions have identified a wider process operating window with increased low-viscosity component concentration. The data confirm that statistical tools make quantitative predictions for the effects of experimental process variables, in accordance with the expected qualitative trends towards process optimisation, providing scope towards its application in scaled-up industrial processes.

Ablation of Potassium-Chloride Cotransporter Type 3 (Kcc3) in Mouse Causes Multiple Cardiovascular Defects and Isosmotic Polyuria.

Inactivation of Kcc3 in a mixed 129/Sv×C57BL/6 mouse background has been previously found to increase systemic blood pressure (BP) through presumed neurogenic mechanisms. Yet, while this background is generally not considered ideal to investigate the cardiovascular system, KCC3 is also expressed in the arterial wall and proximal nephron. In the current study, the effects of Kcc3 ablation was investigated in a pure rather than mixed C57BL/6J background under regular- and high-salt diets to determine whether they could be mediated through vasculogenic and nephrogenic mechanisms. Aortas were also assessed for reactivity to pharmacological agents while isolated from the influence of sympathetic ganglia. This approach led to the identification of unforeseen abnormalities such as lower pulse pressure, heart rate, aortic reactivity and aortic wall thickness, but higher diastolic BP, left ventricular mass and urinary output in the absence of increased catecholamine levels. Salt loading also led systolic BP to be higher, but to no further changes in hemodynamic parameters. Importantly, aortic vascular smooth muscle cells and cardiomyocytes were both found to express KCC3 abundantly in heterozygous mice. Hence, Kcc3 inactivation in our model caused systemic vascular resistance and ventricular mass to increase while preventing extracellular fluid volume to accumulate. Given that it also affected the physiological properties of aortas in vitro, vasculogenic mechanisms could therefore account for a number of the hemodynamic abnormalities observed.

Improved GRACE regional mass balance estimates of the Greenland ice sheet cross-validated with the input–output method

Abstract. In this study, we use satellite gravimetry data from the Gravity Recovery and Climate Experiment (GRACE) to estimate regional mass change of the Greenland ice sheet (GrIS) and neighboring glaciated regions using a least squares inversion approach. We also consider results from the input–output method (IOM). The IOM quantifies the difference between the mass input and output of the GrIS by studying the surface mass balance (SMB) and the ice discharge (D). We use the Regional Atmospheric Climate Model version 2.3 (RACMO2.3) to model the SMB and derive the ice discharge from 12 years of high-precision ice velocity and thickness surveys. We use a simulation model to quantify and correct for GRACE approximation errors in mass change between different subregions of the GrIS, and investigate the reliability of pre-1990s ice discharge estimates, which are based on the modeled runoff. We find that the difference between the IOM and our improved GRACE mass change estimates is reduced in terms of the long-term mass change when using a reference discharge derived from runoff estimates in several subareas. In most regions our GRACE and IOM solutions are consistent with other studies, but differences remain in the northwestern GrIS. We validate the GRACE mass balance in that region by considering several different GIA models and mass change estimates derived from data obtained by the Ice, Cloud and land Elevation Satellite (ICESat). We conclude that the approximated mass balance between GRACE and IOM is consistent in most GrIS regions. The difference in the northwest is likely due to underestimated uncertainties in the IOM solutions.

Synthesis and characterization of CuO nanoparticles using strong base electrolyte through electrochemical discharge process

In the present study, cupric oxide (CuO) nanoparticles were synthesized by electrochemical discharge process using strong base electrolytes. The experiments were carried out separately using NaOH and KOH electrolytes. The mass output rate and the crystal size were obtained with variation of the rotation speed of magnetic stirrer for both types of electrolytes. The mass output rate of CuO nanoparticles increased with the increase in the speed of rotation, and, after an optimum speed, it started decreasing. However, the size of the particles reduced with the increase of the rotation speed. The crystal plane of the obtained CuO nanoparticles was similar for both the electrolytes whereas the yield of nanoparticles was higher in KOH as compared with NaOH under the same experiment conditions. In this set of experiments, the maximum output rates obtained were 21.66 mg h−1 for NaOH and 24.66 mg h−1 for KOH at 200 rpm for a single discharge arrangement. The average crystal size of CuO particles obtained was in the range of 13–18 nm for KOH electrolyte and 15–20 nm for NaOH electrolyte. Scanning electron microscopy images revealed that flower-like and caddice clew-shaped CuO nanocrystalline particles were synthesized by the electrochemical discharge process. Fourier transform infrared spectrum showed that the CuO nanoparticles have a pure and monolithic phase. UV–vis–NIR spectroscopy was used to monitor oxidation course of Cu → CuO and the band gap energy was measured as 2 and 2.6 eV for CuO nanoparticle synthesized in NaOH and KOH solutions, respectively.

Reprint of "Experiments and discrete element simulation of the dosing of cohesive powders in a simplified geometry"

We perform experiments and discrete element simulations on the dosing of cohesive granular materials in a simplified geometry. The setup is a canister box where the powder is dosed out through the action of a constant-pitch coil feeder connected to a motor. A dosing step consists of a rotation followed by a period of rest before the next step. From the experiments, we report on the operational performance of the dosing process through a variation of dosage time, coil pitch and initial powder filling mass. We find that the mass per dose shows an increasing linear dependence on the dosage time and rotation speed. In contrast, the mass output from the canister is inversely proportional (as expected) to an increase in the number of coils.After calibrating the interparticle friction and cohesion, we show that DEM simulations with upscaled particles can quantitatively reproduce the experimental findings for smaller masses but also overestimate arching and blockage. For some parameters, with appropriate homogenization tools, further insights into macroscopic fields can be obtained.This work shows that the calibration of (upscaled) meso-particle properties is a viable approach to overcome the untreatable number of particles inherent in experiments with fine, cohesive powders and thus opens the gateway to simulating their flow in more complex geometries.

A comparison between microalgae virtual biorefinery arrangements for bio-oil production based on lab-scale results

Bio-oils are typically produced by pyrolysis processes. Bio-oils can be used directly in a generator to produce electricity or upgraded to produce transportation fuels. Nowadays the interest is that they come out in a biorefinery context. This paper compares bio-oil production within three possible procedures. Targeting the bio-oil product, in virtual biorefinery #1, microalgae is processed by solvent ultrasound-assisted extraction, and lipids follow transesterification; in virtual biorefinery #2, bio-oil comes out from fresh microalgae pyrolysis, and, finally, in virtual biorefinery #3, lipid extraction leftovers proceed for slow pyrolysis. Solvent ultrasound-assisted extraction and slow pyrolysis are tested and measured experimentally using three microalgae as feedstock: Chlorella vulgaris, Nannochloropsis oculata, and Scenedesmus obliquus. These stand-alone processes are analyzed aiming to provide the best option in a virtual biorefinery context. Although very fast/slow pyrolysis produces markedly different products, previous thermogravimetry analysis allowed choosing an adequate pyrolysis temperature. Nevertheless, the influence of temperature, catalyst and nitrogen flow is depicted. The comparison indicators for final remarks relate to final energy consumption and greenhouse gas emissions. Conditions that favor bio-oil production may not be favorable in terms of energy required per mass or energy output. If mass allocation criterion is used lipid extraction followed by slow pyrolysis of the leftovers is advantageous over slow pyrolysis of fresh dry microalgae. Still the fossil energy input largely surpasses the bio-oil energy content.

Experiments and discrete element simulation of the dosing of cohesive powders in a simplified geometry

We perform experiments and discrete element simulations on the dosing of cohesive granular materials in a simplified geometry. The setup is a canister box where the powder is dosed out through the action of a constant-pitch coil feeder connected to a motor. A dosing step consists of a rotation followed by a period of rest before the next step. From the experiments, we report on the operational performance of the dosing process through a variation of dosage time, coil pitch and initial powder filling mass. We find that the mass per dose shows an increasing linear dependence on the dosage time and rotation speed. In contrast, the mass output from the canister is inversely proportional (as expected) to an increase in the number of coils.After calibrating the interparticle friction and cohesion, we show that DEM simulations with upscaled particles can quantitatively reproduce the experimental findings for smaller masses but also overestimate arching and blockage. For some parameters, with appropriate homogenization tools, further insights into macroscopic fields can be obtained.This work shows that the calibration of (upscaled) meso-particle properties is a viable approach to overcome the untreatable number of particles inherent in experiments with fine, cohesive powders and thus opens the gateway to simulating their flow in more complex geometries.

The importance of considering animal body mass in IPCC greenhouse inventories and the underappreciated role of wild herbivores.

Methane is an important greenhouse gas, but characterizing production by source sector has proven difficult. Current estimates suggest herbivores produce ~20% (~76-189Tgyr(-1) ) of methane globally, with wildlife contributions uncertain. We develop a simple and accurate method to estimate methane emissions and reevaluate production by wildlife. We find a strikingly robust relationship between body mass and methane output exceeding the scaling expected by differences in metabolic rate. Our allometric model gives a significantly better fit to empirical data than IPCC Tier 1 and 2 calculations. Our analysis suggests that (i) the allometric model provides an easier and more robust estimate of methane production than IPCC models currently in use; (ii) output from wildlife is much higher than previously considered; and (iii) because of the allometric scaling of methane output with body mass, national emissions could be reduced if countries favored more, smaller livestock, over fewer, larger ones.

Functional Morphology of the Forelimb of the Nine-Banded Armadillo (Dasypus novemcinctus): Comparative Perspectives on the Myology of Dasypodidae

The nine-banded armadillo, Dasypus novemcinctus, is a member of the family Dasypodidae, which contains all extant species of armadillos and represents the most diverse group of xenarthran mammals by their speciation, form, and range of scratch-digging ability. This study aims to identify muscle traits that reflect specialization for fossorial habit by observing forelimb structure in D. novemcinctus and comparing it among armadillos using available myological data. A number of informative traits were observed in D. novemcinctus and among Dasypodidae, including the absence of m. rhomboideus profundus, the variable presence of a m. articularis humeri and m. coracobrachialis, two heads of m. triceps brachii with scapular origin, and a lack of muscle mass devoted to antebrachial supination. Muscle mass and myosin heavy chain (MHC) isoform content were also quantified from our forelimb dissections. New osteological indices are additionally calculated and reported for D. novemcinctus. Collectively, the findings emphasize muscle mass and power output for limb retraction and specialization of the distal limb for sustained purchase of soil by strong pronation and carpal/digital flexion. Moreover, the myological traits assessed here provide a valuable resource for interpretation of muscle architecture specializations among digging mammals and future reassessment of armadillo phylogeny.

Loss of Lung Health from Young Adulthood and Cardiac Phenotypes in Middle Age.

Chronic lung diseases are associated with cardiovascular disease. How these associations evolve from young adulthood forward is unknown. Understanding the preclinical history of these associations could inform prevention strategies for common heart-lung conditions. To use the Coronary Artery Risk Development in Young Adults (CARDIA) study to explore the development of heart-lung interactions. We analyzed cardiac structural and functional measurements determined by echocardiography at Year 25 of CARDIA and measures of pulmonary function over 20 years in 3,000 participants. Decline in FVC from peak was associated with larger left ventricular mass (β = 6.05 g per SD of FVC decline; P < 0.0001) and greater cardiac output (β = 0.109 L/min per SD of FVC decline; P = 0.001). Decline in FEV1/FVC ratio was associated with smaller left atrial internal dimension (β = -0.038 cm per SD FEV1/FVC decline; P < 0.0001) and lower cardiac output (β = -0.070 L/min per SD of FEV1/FVC decline; P = 0.03). Decline in FVC was associated with diastolic dysfunction (odds ratio, 3.39; 95% confidence interval, 1.37-8.36; P = 0.006). Patterns of loss of lung health are associated with specific cardiovascular phenotypes in middle age. Decline in FEV1/FVC ratio is associated with underfilling of the left heart and low cardiac output. Decline in FVC with preserved FEV1/FVC ratio is associated with left ventricular hypertrophy and diastolic dysfunction. Cardiopulmonary interactions apparent with common complex heart and lung diseases evolve concurrently from early adulthood forward.

The Effects of Different Levels Chlorell Microalgae on Performance and Immune Response of Laying Hens Under Heat Stress Condition

This study was conducted to determine the effects of different levels microalgae Chlorell sp. on performance of laying hens under heat stress condition. A completely randomized design experiment, with 7 replicates and 6 treatments (9 birds per replicate) was carried out by allotting 378 white Lohman strain laying hens at 65 weeks of age. Six experimental treatments were continual addition of 0, 100, 200, 300,400 ppm microalgae Chlorell and 400 ppm toein to drinking warer were fed to laying hens for 9 weeks. Egg production, egg weight, egg mass output and feed intake were determined. Antibody production against sheep red blood cells (SRBC) also was measured. Data were analyzed by ANOVA using General Linear Models procedure of SAS software and comparison of means were compared using Duncan’s multiple range test. The results of this experiment showed that microalgae Chlorell had no effect on productive performance. Adding microalgae Chlorell to the drinking water improved immune response of laying hens and a more positive effect was observed when 400 ppm added to the water. It is concluded that the addition of microalgae Chlorell to the water drinking of laying hens improved immune response of laying hens.DOI: http://dx.doi.org/10.3126/ijls.v9i2.12058 International Journal of Life Sciences 9 (2) : 2015; 71-74

Production of Pigment Enriched Desi Chicken Eggs by Feeding of Tagetes erecta Petals

The present study was carried out with an aim of enriching desi chicken egg with carot- enoid pigment and to improve its colour of consumers' preference. A total of 96 adult Nicobari fowls at the age of 30 weeks were subjected to four dietary treatments consisting of 1 (T-1), 2 (T-2), and 3 (T-3) g marigold dried petal powder per day per hen and control (c). The mean egg production pa- rameters, egg quality characters and reproductive trait were recorded for 120 days. Marigold feeding to Nicobari fowl up to 3 g did not show any adverse effect on the palatability of feed, egg production performance, egg weight, egg mass output, hatchability and feed efficiency. Significant (P<0.05) improvement in the Roch yolk colour score from 4 to 8 reflected the enrichment of caroteinoid pig- ments in egg yolk. Feeding of dried Marigold petals up to 3 g per hen per day as supplemental feed additive for rural poultry could enrich carotenoid pigments in desi eggs and thereby could improve yolk colour of consumer's preference under semi-intensive system of management to meet the grow- ing demand and changing consumers need for enriched poultry production.

Laboratory Tests of Idlers Rotational Resistance – Selected Issues

Idlers rotational resistance has a significant impact on energy consumption of belt conveyors. The conducted analyses showed that this component can account for 30% of total belt conveyor resistance to motion (Gładysiewicz and Kawalec, 2008; Błażej et al., 2013). The causes for idlers rotational resistance including structural factors were precisely determined in (Gładysiewicz and Król, 2005). Since then, many works have been carried out with the aim to assess the quality of idlers and to acquire the knowledge necessary to optimize belt conveyor haulage process (Bukowski et al., 2011a, Gładysiewicz and Król, 2009; 2012). It was due to, inter alia, the fact that the calculations of belt conveyors designs are based only on empirical relationships which give a good approximation for laboratory tested idlers, but are imprecise in relation to new construction solutions of idlers.The results of research and development works carried out at the Wroclaw University of Technology have shown that one of the conditions for successful reduction of the energy consumption of belt conveyors drives is to use high-quality idlers characterized by low rotational resistance under a wide range of working loads (Bukowski et al., 2011c, Król and Kisielewski 2014). The studies allowed expanding knowledge about idlers rotational resistance and about the impact of working loads on belt conveyors resistance to motion and showed that idlers rotational resistance depends also on value of the idlers radial loads caused by transported masses. A series of laboratory and operational tests based on using advanced analytical tools and modern measuring techniques have been carried out and allowed to observe dependence between instantaneous mass output of belt conveyor and loads of individual idlers in the set. This allowed determining the dependence of idlers rotational resistance as a function of random loading of transported bulk material (Bukowski 2012, Król 2013).

Constraining the recent mass balance of Pine Island and Thwaites glaciers, West Antarctica, with airborne observations of snow accumulation

Abstract. In Antarctica, uncertainties in mass input and output translate directly into uncertainty in glacier mass balance and thus in sea level impact. While remotely sensed observations of ice velocity and thickness over the major outlet glaciers have improved our understanding of ice loss to the ocean, snow accumulation over the vast Antarctic interior remains largely unmeasured. Here, we show that an airborne radar system, combined with ice-core glaciochemical analysis, provide the means necessary to measure the accumulation rate at the catchment-scale along the Amundsen Sea coast of West Antarctica. We used along-track radar-derived accumulation to generate a 1985–2009 average accumulation grid that resolves moderate- to large-scale features (&gt;25 km) over the Pine Island–Thwaites glacier drainage system. Comparisons with estimates from atmospheric models and gridded climatologies generally show our results as having less accumulation in the lower-elevation coastal zone but greater accumulation in the interior. Ice discharge, measured over discrete time intervals between 1994 and 2012, combined with our catchment-wide accumulation rates provide an 18-year mass balance history for the sector. While Thwaites Glacier lost the most ice in the mid-1990s, Pine Island Glacier's losses increased substantially by 2006, overtaking Thwaites as the largest regional contributor to sea-level rise. The trend of increasing discharge for both glaciers, however, appears to have leveled off since 2008.