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We demonstrate a convolutional neural network (CNN) for multi-class breast tissue classification as adipose tissue, benign dense tissue, or malignant tissue, using multi-channel optical coherence tomography (OCT) and attenuation images, and a novel Matthews correlation coefficient (MCC)-based loss function that correlates more strongly with performance metrics than the commonly used cross-entropy loss. We hypothesized that using multi-channel images would increase tumor detection performance compared to using OCT alone. 5,804 images from 29 patients were used to fine-tune a pre-trained ResNet-18 network. Adding attenuation images to OCT images yields statistically significant improvements in several performance metrics, including benign dense tissue sensitivity (68.0% versus 59.6%), malignant tissue positive predictive value (PPV) (79.4% versus 75.5%), and total accuracy (85.4% versus 83.3%), indicating that the additional contrast from attenuation imaging is most beneficial for distinguishing between benign dense tissue and malignant tissue.

UNLABELLED: Breast-conserving surgery (BCS) is commonly used for the treatment of early-stage breast cancer. Following BCS, approximately 20% to 30% of patients require reexcision because postoperative histopathology identifies cancer in the surgical margins of the excised specimen. Quantitative micro-elastography (QME) is an imaging technique that maps microscale tissue stiffness and has demonstrated a high diagnostic accuracy (96%) in detecting cancer in specimens excised during surgery. However, current QME methods, in common with most proposed intraoperative solutions, cannot image cancer directly in the patient, making their translation to clinical use challenging. In this proof-of-concept study, we aimed to determine whether a handheld QME probe, designed to interrogate the surgical cavity, can detect residual cancer directly in the breast cavity in vivo during BCS. In a first-in-human study, 21 BCS patients were scanned in vivo with the QME probe by five surgeons. For validation, protocols were developed to coregister in vivo QME with postoperative histopathology of the resected tissue to assess the capability of QME to identify residual cancer. In four cavity aspects presenting cancer and 21 cavity aspects presenting benign tissue, QME detected elevated stiffness in all four cancer cases, in contrast to low stiffness observed in 19 of the 21 benign cases. The results indicate that in vivo QME can identify residual cancer by directly imaging the surgical cavity, potentially providing a reliable intraoperative solution that can enable more complete cancer excision during BCS. SIGNIFICANCE: Optical imaging of microscale tissue stiffness enables the detection of residual breast cancer directly in the surgical cavity during breast-conserving surgery, which could potentially contribute to more complete cancer excision.

• Renewable energy developments, including offshore wind farms have been identified as a key component in international efforts to mitigate climate change and its impact on biodiversity. This has led to an increasing number of offshore wind farms around the UK, however, these can have negative impacts on seabird populations. • Population Viability Analysis (PVA) is frequently used to quantify these potential negative effects on seabird populations and is a vital part of the consenting process. However, a lack of empirical data on many aspects of seabird demography means that there can be considerable uncertainty in these assessments. • Black-legged Kittiwake Rissa tridactyla populations are thought to be particularly sensitive to additional mortality caused by collision with offshore wind turbines and are often highlighted as a feature of Special Protection Areas (SPAs). Offshore wind farms, therefore, have been identified as potentially causing an adverse effect on site integrity at some SPAs. • Despite being a relatively well-studied species, there is still much uncertainty in our knowledge of Kittiwake demographic rates and meta-population dynamics, which impedes our ability to accurately assess the way populations might respond to additional wind farm-induced mortality. • The Offshore Wind Strategic Monitoring and Research Forum (OWSMRF) identified a large-scale colour-ringing programme of Kittiwake colonies across the UK as one potential approach for improving empirical estimates of Kittiwake demographic rates. • Therefore, the main aim of this project was to determine the extent to which colour-ringing can be used to obtain reliable baseline estimates of key demographic rates in Kittiwake populations to improve the realism of demographic models assessing the population impacts of offshore wind farms, and thereby reduce uncertainty around these predicted impacts.

An experimental program is currently underway at the National Ignition Facility (NIF) to compress deuterium and tritium (DT) fuel to densities and temperatures sufficient to achieve fusion and energy gain. The primary approach being investigated is indirect drive inertial confinement fusion (ICF), where a high-Z radiation cavity (a hohlraum) is heated by lasers, converting the incident energy into x-ray radiation which in turn drives the DT fuel filled capsule causing it to implode. Previous experiments reported DT fuel gain exceeding unity [O.A. Hurricane et al., Nature 506, 343 (2014)] and then exceeding the kinetic energy of the imploding fuel [S. Le Pape et al., Phys. Rev. Lett. 120, 245003 (2018)]. We report on recent experiments that have achieved record fusion neutron yields on NIF, greater than 100 kJ with momentary fusion powers exceeding 1PW, and have for the first time entered the burning plasma regime where fusion alpha-heating of the fuel exceeds the energy delivered to the fuel via compression. This was accomplished by increasing the size of the high-density carbon (HDC) capsule, increasing energy coupling, while controlling symmetry and implosion design parameters. Two tactics were successful in controlling the radiation flux symmetry and therefore the implosion symmetry: transferring energy between laser cones via plasma waves, and changing the shape of the hohlraum. In conducting these experiments, we controlled for known sources of degradation. Herein we show how these experiments were performed to produce record performance, and demonstrate the data fidelity leading us to conclude that these shots have entered the burning plasma regime.

Publicaciones: ct026

Symbolic number knowledge is strongly related to mathematical performance for both children and adults. We present a model of symbolic number relations in which increasing skill is a function of hierarchical integration of symbolic associations. We tested the model by contrasting the performance of two groups of adults. One group was educated in China (n = 71) and had substantially higher levels of mathematical skill compared to the other group who was educated in Canada (n = 68). Both groups completed a variety of symbolic number tasks, including measures of cardinal number knowledge (number comparisons), ordinal number knowledge (ordinal judgments) and arithmetic fluency, as well as other mathematical measures, including number line estimation, fraction/algebra arithmetic and word problem solving. We hypothesized that Chinese-educated individuals, whose mathematical experiences include a strong emphasis on acquiring fluent access to symbolic associations among numbers, would show more integrated number symbol knowledge compared to Canadian-educated individuals. Multi-group path analysis supported the hierarchical symbol integration hypothesis. We discuss the implications of these results for understanding why performance on simple number processing tasks is persistently related to measures of mathematical performance that also involve more complex and varied numerical skills.

The effects of different pelleting temperatures on the activity of cellulase, bacterial amylase, fungal amylase, and pentosanase were tested. Samples of a commercial barley-wheat-soybean diet containing different enzyme preparations were pelleted at 60, 70, 80, 90, and 100 C (pellet temperature measured at the die outlet) through a die containing holes 2.5 mm in diameter. Enzymatic analyses were conducted on either soluble substrates or by measuring the ability of the tested enzymes to decrease the viscosity of the diet. Measurements made on soluble substrates suggest that cellulase, fungal amylase, and pentosanase maintained activity when being pelleted at temperatures up to 80 C and bacterial amylase maintained activity at temperatures up to 90 C. Pentosanase and amylases showed little or no effect on the viscosity of the diet. Cellulase addition decreased the viscosity at all temperature levels, even after being pelleted at 90 and 100 C (P < 0.05). No cellulolytic activity was detected on the soluble substrate after these pelleting temperatures. Measurements on a soluble substrate might therefore not always reflect the true stability of a preparation because the ability of a carbohydrase to decrease the viscosity of the digesta is important to its effect in the gastrointestinal tract. Measurements on soluble substrates suggest that cellulase, fungal amylase, and pentosanase can be pelleted at temperatures up to at least 80 C and bacterial amylase up to 90 C without a considerable loss in analyzed activity

The ability of different enteric pathogens and coliforms to trigger agglutination of yeast cells (Saccharomyces cerevisiae, NCYC 1026) and a yeast cell wall preparation (MOS) was examined. Five of seven strains of Escherichia coli and 7 of 10 strains of Salmonella typhimurium and Salmonella enteritidis agglutinated MOS and Sac. cerevisiae cells. Strains of Salmonella choleraesuis, Salmonella pullorum, and Campylobacter did not lead to agglutination. Two strains that agglutinated MOS (S. typhimurium 29E and Salmonella dublin) and one nonagglutinating strain (S. typhimurium 27A) were selected as challenge organisms for in vivo studies in chicks under controlled conditions. In a series of three trials in which 3-d-old chicks were orally challenged with 10(4) cfu of S. typhimurium 29E, birds receiving 4,000 ppm of dietary MOS had reduced cecal S. typhimurium 29E concentrations (5.40 vs 4.01 log cfu/ g; P < 0.05) at Day 10. In a second series of three trials with S. dublin as challenge organism, the number of birds that tested salmonella positive in the ceca at Day 10 was less when MOS was part of the diet (90 vs 56%; P < 0.05). To test the effect of MOS on concentrations of bacteria that do not express Type 1 fimbriae, a challenge trial was conducted with S. typhimurium 27A. However, strain 27A did not colonize the birds sufficiently to evaluate whether MOS affected its cecal concentration. Mannanoligosaccharide did not significantly reduce the concentrations of cecal coliforms (P < 0.10) although they were numerically lower. It had no effect on cecal concentrations of lactobacilli, enterococci, anaerobic bacteria, lactate, volatile fatty acid, or cecal pH

Editorial

The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument is a multipurpose high-contrast imaging platform designed for the discovery and detailed characterization of exoplanetary systems and serves as a testbed for high-contrast imaging technologies for ELTs. It is a multi-band instrument which makes use of light from 600 to 2500nm allowing for coronagraphic direct exoplanet imaging of the inner 3 lambda/D from the stellar host. Wavefront sensing and control are key to the operation of SCExAO. A partial correction of low-order modes is provided by Subaru's facility adaptive optics system with the final correction, including high-order modes, implemented downstream by a combination of a visible pyramid wavefront sensor and a 2000-element deformable mirror. The well corrected NIR (y-K bands) wavefronts can then be injected into any of the available coronagraphs, including but not limited to the phase induced amplitude apodization and the vector vortex coronagraphs, both of which offer an inner working angle as low as 1 lambda/D. Non-common path, low-order aberrations are sensed with a coronagraphic low-order wavefront sensor in the infrared (IR). Low noise, high frame rate, NIR detectors allow for active speckle nulling and coherent differential imaging, while the HAWAII 2RG detector in the HiCIAO imager and/or the CHARIS integral field spectrograph (from mid 2016) can take deeper exposures and/or perform angular, spectral and polarimetric differential imaging. Science in the visible is provided by two interferometric modules: VAMPIRES and FIRST, which enable sub-diffraction limited imaging in the visible region with polarimetric and spectroscopic capabilities respectively. We describe the instrument in detail and present preliminary results both on-sky and in the laboratory., Comment: Accepted for publication, 20 pages, 10 figures

In this paper, the button shear tests of seven kinds of epoxy used for corner/edge bonding of BGA mezzanine connectors are performed firstly for determining adhesive strength between the epoxies and each relevant surface material. The effect of corner/edge bonding epoxy on the board level solder joint reliability of BGA connectors is also investigated including mechanical drop and 4-point bending tests. In addition, the pre-conditioning effect of thermal aging (1000 hours at 125°C) and accelerated temperature cycling (ATC, -40∼125°C, 500 cycles) on the reliability of connectors with corner/edge bonding epoxy is discussed. The failure modes and fracture strengths of the button shear and boardlevel tests are cross-referenced for comparison and assessed for correlation. The results from the present study not only contribute to the characterization and selection of corner/edge bonding epoxies for BGA connectors, but also improve the understanding of the corresponding relationship between simple button shear and the more complex and costly boardlevel reliability tests. © 2010 IEEE.

Pad cratering is one of the dominant failure modes that occur in various board level reliability tests, especially under the dynamic loading. In recent years, the increasing propensity of pad cratering due to the implementation of the lead-free technology calls for the necessity of re-assessment of PWB qualification related to the pad cratering resistance. The objective of the present study is to establish a test method for evaluating the pad cratering resistance of PWB and studying the PWB degradation mechanism subject to different high temperature conditions. Three kinds of PWB with different resin systems were investigated, including one phenolic-cured system board and two dicy-cured system boards. Tg and Td of the selected PWBs were characterized using TMA and TGA. The detailed cold ball pull test procedure is presented and different pull jaws with/without standoff are evaluated in this paper. The effects of multiple reflows, thermal aging and temperature cycling on the pad cratering resistance of PWBs are discussed as well. © 2010 IEEE.

Board level solder joint reliability was evaluated using a 4-point monotonic bending test on different BGA package assemblies, including a 51x51 mm 2400 CBGA and a 40x40 mm 1517 PBGA. The edgebond epoxy was applied between the package samples and solder-attached printed wiring boards (PWBs). During the bending test, the PWB strain, bending force and daisy-chain resistance were monitored in real time. The daisy-chain resistance and PWB strain-rate during the bending test were cross-referenced for detailed comparison. The test results indicated that the PWB strain-rate showed an obvious change at the moment of package failure. The PWB strain-rate can be a useful monitoring method for detecting the onset of the solder joint failure during the monotonic bending test. ©2009 IEEE.

This paper details the outgassing process during epoxy degradation and evaluates the corresponding influence on adjacent PWB pads for immersion Ag (ImAg) plated circuit boards. Three commercial epoxy adhesives used for edgebonding of surface-mount (SMT) components were investigated. Scanning electron microscope (SEM) analysis and electron dispersive spectroscopy (EDS) was carried out to investigate the surface of the contaminated ImAg pads. Chemical states of the elements transferred to the pads were analyzed by X-ray Photoelectron Spectroscopy (XPS). The results from the present study showed some ingredients in the adhesives may be thermo-oxidized to gaseous by-products in the presence of oxygen and migrate out from the epoxy body, contaminating the adjacent ImAg pads. Further research will be needed to verify whether these gaseous by-products also contaminate surrounding components, and result in corrosionrelated reliability failures. © 2009 IEEE.

In this paper, the material characteristics of six epoxies used for corner/edge-bonding are analyzed and compared to board-level mechanical reliability test. An innovative material characterization approach, button shear testing, provided an expedient method of determining adhesive strength between the epoxies and each relevant surface material. The boardlevel test included mechanical shock test. A number of SMT test devices are evaluated, including 1849 CBGA packages, and 190 ball count mezzanine connectors. The failure modes and fracture strengths of the material characterization tests and board-level tests are cross-referenced for comparison, and assessed for correlation. The results from the present study not only contribute to the characterization and selection methods of corner/edge-bonding epoxies, but also improve understanding of the corresponding relationship between material characterization testing and the more complex and costly board-level reliability tests. © 2009 IEEE.

Solder joint reliability concerns are increasing exponentially with the continuous push for device miniaturization, and the expanded use in portable electronic products. In order to predict the solder joint reliability under drop conditions, it is important to increase the testing speed of package level test methods, such as high-speed solder ball shear and pull. Traditional ball shear and pull tests are not considered suitable for evaluation of joint reliability under drop loading, since the applied test speeds, usually lower than 5 mm/s, are well below the impact velocity applied to the solder joint in a drop test. Recently, high-speed shear and pull test equipment (Dage 4000HS) with testing speeds beyond 1,000 mm/s has become available. The present study continues the efforts reported recently and investigates the effect of thermal aging on the attachment strength and fracture energy of SnAgCu lead-free solder balls during high speed ball shear/pull tests. The ball shear test speeds ranged from 100 mm/s to 1,000 mm/s, while the ball pull test speeds ranged from 5 mm/s to 100 mm/s. The test specimens were aged at 125°C or 150°C for durations of 100, 300 and 500 hrs, with some additional samples exposed up to 1,000 hrs. Correlations were established between solder joint fracture force/energy and IMC thickness, and between fracture energy and failure mode. © 2007 IEEE.

A comprehensive solder joint reliability study was conducted using both high-speed solder ball shear/pull and board level drop testing (BLDT). The samples were divided into groups which were subject to various periods of thermal aging (125°C, up to 500 hours) in order to accelerate the formation of intermetallic compound (IMC) in the solder joints. The ball shear tests ranged from 10 mm/s to 3,000 mm/s while the ball pull tests ranged from 5 mm/s to 500 mm/s. A total of 6 unique package constructions were evaluated, ranging from a 316 PBGA (27 mm, sq) to a 2,395 CBGA (51 mm, sq). The samples used SAC lead-free solder balls and a variety of pad surface finishes. Detailed failure analyses were performed to identify the failed solder joints and corresponding failure modes. The failure modes and loading speeds of ball shear and ball pull tests were cross-referenced with the mechanical drop tests for comparison. Correlation models were established relating drops-to-failure with both solder ball fracture force and energy. © 2007 IEEE.

Myocardial contrast echocardiography (MCE) has potential value in the assessment and quantitation of myocardial perfusion defects. However, the severity of stenosis detectable by MCE and its diagnostic accuracy remain undefined. Thus, we produced coronary stenoses of variable severity and quantified their effect on MCE

Human keratinocytes are known to kill Candida albicans in vitro, but the mechanism of killing is not yet understood. Here, we demonstrate that spontaneous, ultraviolet-B-light-induced, alpha-melanocyte-stimulating-hormone-induced, and interleukin-8-induced Candida killing by keratinocytes can be inhibited with mannan and mannosylated bovine serum albumin (Man-BSA). A polyclonal goat serum raised against the human macrophage mannose receptor stained suprabasal keratinocytes, but no staining was observed on keratinocytes with a monoclonal antibody (mAb15) specific for the human macrophage mannose receptor. Mannose-affinity chromatography of keratinocyte extract isolated a 200 kDa protein, and on the Western blot the goat antiserum reacted with a 200 kDa protein. In radioligand binding studies, the binding of 125I-Man-BSA to human keratinocytes was inhibited by mannan in a concentration-dependent manner. Analysis of the binding revealed a single class keratinocyte mannose receptor with a KD of 1.4 x 10(-8) M and a Bmax of 1 x 10(4) binding sites per cell. The binding of 125I-Man- BSA to keratinocytes proved to be time-dependent, acid-precipitable, and Ca2+- and trypsin-sensitive. After trypsinization the receptors underwent a rapid recovery at 37 degrees C. These results demonstrate the presence of mannose receptor on human keratinocytes, and its active involvement in the killing of Candida albicans.

This document provides the test plan and guidelines for the experimental evaluation of video transmissions of radiographs over the Remote Medical Diagnosis System (RMDS) advanced development model terminals. The objectives of this evaluation were (1) to determine which, if any, of the various operational modes of the RMDS ADM terminal would satisfy the image fidelity requirements for clinical diagnosis of video-transmitted radiographs and (2) to establish quantitative and qualitative values or relationships delineating the image fidelity requirements necessary for professional radiologists to make correct and confident diagnoses from video-transmitted radiographs. (Author)

College of Engineering and Computer Science, Thesis (M.S.E.)--Florida Atlantic University, 1986., Summary: This report presents a detailed approach to the problem of determining expected shipping delays that are caused by inadequate channel width. Data collection and analysis is accomplished for the shipping industry of Tampa Bay, Florida. Historical data and cargo projection are used to develop the expected shipping traffic density and distribution for the year 2000. An overview of a computer model that simulates the shipping traffic and accounts for delays due to channel width is presented. A sensitivity analysis performed on the model to determine the effect each input variable has on shipping delays. The results are presented in the form of shipping delay curves for seven types of vessels over a range of channel widths., Collection: FAU Electronic Theses and Dissertations Collection

College of Engineering and Computer Science, Thesis (M.S.E.)--Florida Atlantic University, 1985., Summary: The time series method of Auto Regressive Moving Average (ARMA) is applied to the problem of real time ship motion prediction. The theory of Scalar input Scalar output ARMA (n, n-1) model and the same extended to multiple series as vector, ARMAV model have been concisely presented. The field experimental procedure for roll measurement of vessel at sea and barge model test procedure for heave and pitch measurements are discussed. The time series data of roll is analysed as a scalar ARMA (n, n-1) model and the results of prediction are presented. The model test data of heave, pitch and wave were analysed as ARMAV (n,n-1) vector model and the results are presented. The model test and experimental results demonstrate the feasibility of ARMA modeling procedure as a valuable tool in the area of real time ship motion prediction., Collection: FAU Electronic Theses and Dissertations Collection

College of Engineering and Computer Science, Thesis (M.S.E.)--Florida Atlantic University, 1985., Summary: The hydrodynamic interactions between ships in confined waters, restricted in width and depth, is analysed using a numerical surface singularity method called the Panel method. Based on potential flow and rigid free surface assumptions, a source distribution is utilized over the boundary surfaces to model the flow. The strength of the source distribution is obtained on satisfying the normal kinematic boundary conditions, i.e. as a solution of an integral equation. Discretization of the boundary surfaces yields a system of linear algebraic equations corresponding to the boundary integral equation, which then is solved numerically. From the singularity distribution, the velocity components, pressure coefficients and finally the interaction loads are calculated., Collection: FAU Electronic Theses and Dissertations Collection

College of Engineering and Computer Science, Thesis (M.S.E.)--Florida Atlantic University, 1985., Summary: Edge waves are the longshore, trapped waves; their amplitude diminishes exponentially seaward from the shoreline. Ursell [1] has shown that there is a family of edge wave solutions of the shallow water equations, and Ball [2] provided a normal mode solution for the exponential beach. This study investigated, experimentally, the excitation of edge waves on a concave exponential beach by waves normally incident on the beach. The experimental investigation included the study of edge wave frequency, amplitude and particle motions. The results indicated that resonance occurs under suitable conditions for edge wave excitation. Viscosity, nonlinearity and defraction at the beach sidewalls reduced agreement between experiments and theory. The effects of these parameters on edge waves should be explored in more detail in further research., Collection: FAU Electronic Theses and Dissertations Collection

Summary: Edge waves are the longshore periodic wave motions that are trapped at the edge of water bodies and play an important role in coastal hydrodynamics. This study presents the experimental investigation of the excitation of synchronous edge waves by waves normally and obliquely incident on a uniformly sloping beach. The experimental results show that the edge wave amplitude is linearly proportional to that of the reflected waves. For a perfectly reflecting beach, the conclusion is consistent with the Rockliff model. The experimental results also indicate that the ratio of the edge wave amplitude to reflected amplitude is linearly proportional to the approach angle., College of Engineering and Computer Science, Thesis (M.S.E.)--Florida Atlantic University, 1987., Collection: FAU Electronic Theses and Dissertations Collection

Experiments were conducted to determine whether a multi-dimensional nonredundant means of encoding information for visual displays could be derived from several encoding dimensions. The effectiveness of geometric-only encoding was compared with geometric-plus-brightness level, flashing rate, and color encoding, with respect to speed and accuracy in performance of two different tasks. Nonredundant use of two and three different colors was found to improve speed and accuracy; the combination of several levels of three different encoding dimensions is detrimental to performance, particularly when three flashing rates are included. (Author)

An experimental investigation was made to compare the relative effectiveness of spatial and alphabetic encoding of information on a visual display. Results showed that simple or partial spatial encoding leads to good performance with respect to speed and accuracy. Where the primary need is rapid detection, the speed of response can be improved by even fairly complex spatial codes. The use of labels to identify the spatial code helps the display operator. (Author)

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The ability of different enteric pathogens and coliforms to trigger agglutination of yeast cells (Saccharomyces cerevisiae, NCYC 1026) and a yeast cell wall preparation (MOS) was examined. Five of seven strains of Escherichia coli and 7 of 10 strains of Salmonella typhimurium and Salmonella enteritidis agglutinated MOS and Sac. cerevisiae cells. Strains of Salmonella choleraesuis, Salmonella pullorum, and Campylobacter did not lead to agglutination. Two strains that agglutinated MOS (S. typhimurium 29E and Salmonella dublin) and one nonagglutinating strain (S. typhimurium 27A) were selected as challenge organisms for in vivo studies in chicks under controlled conditions. In a series of three trials in which 3-d-old chicks were orally challenged with 10(4) cfu of S. typhimurium 29E, birds receiving 4,000 ppm of dietary MOS had reduced cecal S. typhimurium 29E concentrations (5.40 vs 4.01 log cfu/ g; P < 0.05) at Day 10. In a second series of three trials with S. dublin as challenge organism, the number of birds that tested salmonella positive in the ceca at Day 10 was less when MOS was part of the diet (90 vs 56%; P < 0.05). To test the effect of MOS on concentrations of bacteria that do not express Type 1 fimbriae, a challenge trial was conducted with S. typhimurium 27A. However, strain 27A did not colonize the birds sufficiently to evaluate whether MOS affected its cecal concentration. Mannanoligosaccharide did not significantly reduce the concentrations of cecal coliforms (P < 0.10) although they were numerically lower. It had no effect on cecal concentrations of lactobacilli, enterococci, anaerobic bacteria, lactate, volatile fatty acid, or cecal pH

The effects of different pelleting temperatures on the activity of cellulase, bacterial amylase, fungal amylase, and pentosanase were tested. Samples of a commercial barley-wheat-soybean diet containing different enzyme preparations were pelleted at 60, 70, 80, 90, and 100 C (pellet temperature measured at the die outlet) through a die containing holes 2.5 mm in diameter. Enzymatic analyses were conducted on either soluble substrates or by measuring the ability of the tested enzymes to decrease the viscosity of the diet. Measurements made on soluble substrates suggest that cellulase, fungal amylase, and pentosanase maintained activity when being pelleted at temperatures up to 80 C and bacterial amylase maintained activity at temperatures up to 90 C. Pentosanase and amylases showed little or no effect on the viscosity of the diet. Cellulase addition decreased the viscosity at all temperature levels, even after being pelleted at 90 and 100 C (P < 0.05). No cellulolytic activity was detected on the soluble substrate after these pelleting temperatures. Measurements on a soluble substrate might therefore not always reflect the true stability of a preparation because the ability of a carbohydrase to decrease the viscosity of the digesta is important to its effect in the gastrointestinal tract. Measurements on soluble substrates suggest that cellulase, fungal amylase, and pentosanase can be pelleted at temperatures up to at least 80 C and bacterial amylase up to 90 C without a considerable loss in analyzed activity