Part input into a flexible flow system: An evaluation of look-ahead simulation and a fuzzy rule base

Flexible Services and Manufacturing Journal - This article reports an investigation into part-input methods for an implemented flexible flow system (FFS). Two new dynamic methods—look-ahead...     

Improving the upper-limb force feasible set evaluation by muscles maximal isometric force identification and cocontraction factors

In order to improve the evaluation of the force feasible set (FFS) of the upper-limb which is of great interest in the biomechanics field, this study proposes two additional techniques. The first one is based on the identification of the maximal isometric force (MIF) of Hill-based muscles models from sEMG and isometric force measurements at the hand. The second one considers muscles cocontraction.The FFS was computed with an upper-limb musculoskeletal model in three different cases. The first one (M1) considered binary muscular activation and a simple MIF scaling method based on the weight and muscle length of the subject. The second one (M2) introduces cocontraction factors determined from sEMG. The third one (M3) considers the cocontraction factors and the MIF identification. Finally, M1, M2 and M3 are compared with end-effector force measurement.M3 outperforms the two other methods on FFS prediction demonstrating the validity and the usefulness of MIF identification and the consideration of the cocontraction factors.     

Midtarsal locking,the windlass mechanism,and running strike pattern: A kinematic and kinetic assessment

Changes in running strike pattern affect ankle and knee mechanics, but little is known about the influence of strike pattern on the joints distal to the ankle. The purpose of this study was to explore the effects of forefoot strike (FFS) and rearfoot strike (RFS) running patterns on foot kinematics and kinetics, from the perspectives of the midtarsal locking theory and the windlass mechanism. Per the midtarsal locking theory, we hypothesized that the ankle would be more inverted in early stance when using a FFS, resulting in decreased midtarsal joint excursions and increased dynamic stiffness. Associated with a more engaged windlass mechanism, we hypothesized that a FFS would elicit increased metatarsophalangeal joint excursions and negative work in late stance. Eighteen healthy female runners ran overground with both FFS and RFS patterns. Instrumented motion capture and a validated multi-segment foot model were used to analyze midtarsal and metatarsophalangeal joint kinematics and kinetics. During early stance in FFS the ankle was more inverted, with concurrently decreased midtarsal eversion (p < 0.001) and abduction excursions (p = 0.003) but increased dorsiflexion excursion (p = 0.005). Dynamic midtarsal stiffness did not differ (p = 0.761). During late stance in FFS, metatarsophalangeal extension was increased (p = 0.009), with concurrently increased negative work (p < 0.001). In addition, there was simultaneously increased midtarsal positive work (p < 0.001), suggesting enhanced power transfer in FFS. Clear evidence for the presence of midtarsal locking was not observed in either strike pattern during running. However, the windlass mechanism appeared to be engaged to a greater extent during FFS.     

Brightness Analysis by Z-Scan Fluorescence Fluctuation Spectroscopy for the Study of Protein Interactions within Living Cells

Fluorescence fluctuation spectroscopy (FFS) quantifies interactions of fluorescently labeled proteins inside living cells by brightness analysis. Conventional FFS implicitly requires that the sample thickness exceeds the size of the observation volume. This condition is not always fulfilled when measuring cells. Cytoplasmic sections, especially, can be thinner than the axial size of the observation volume. The finite sample thickness introduces a brightness bias which, if not recognized, leads to an erroneous interpretation of the data. To avoid this artifact, we introduce z-scan FFS which consists of a fluorescence intensity z scan through the sample followed by an FFS measurement. To model the experimental z-scan data, a new PSF model had to be introduced. We use the intensity z scan together with the PSF model to determine the geometry of the sample and then extract the brightness from the FFS data. Cells expressing EGFP serve as a model system for testing the experimental approach. We demonstrate that z-scan FFS abolishes the brightness artifact and use the method to determine the oligomerization of cytoplasmic nuclear transport factor 2.     

Differences in muscle activity between natural forefoot and rearfoot strikers during running

Running research has focused on reducing injuries by changing running technique. One proposed method is to change from rearfoot striking (RFS) to forefoot striking (FFS) because FFS is thought to be a more natural running pattern that may reduce loading and injury risk. Muscle activity affects loading and influences running patterns; however, the differences in muscle activity between natural FFS runners and natural RFS runners are unknown. The purpose of this study was to measure muscle activity in natural FFS runners and natural RFS runners. We tested the hypotheses that tibialis anterior activity would be significantly lower while activity of the plantarflexors would be significantly greater in FFS runners, compared to RFS runners, during late swing phase and early stance phase. Gait kinematics, ground reaction forces and electromyographic patterns of ten muscles were collected from twelve natural RFS runners and ten natural FFS runners. The root mean square (RMS) of each muscle?s activity was calculated during terminal swing phase and early stance phase. We found significantly lower RMS activity in the tibialis anterior in FFS runners during terminal swing phase, compared to RFS runners. In contrast, the medial and lateral gastrocnemius showed significantly greater RMS activity in terminal swing phase in FFS runners. No significant differences were found during early stance phase for the tibialis anterior or the plantarflexors. Recognizing the differences in muscle activity between FFS and RFS runners is an important step toward understanding how foot strike patterns may contribute to different types of injury.     

Joint contact loading in forefoot and rearfoot strike patterns during running

Research concerning forefoot strike pattern (FFS) versus rearfoot strike pattern (RFS) running has focused on the ground reaction force even though internal joint contact forces are a more direct measure of the loads responsible for injury. The main purpose of this study was to determine the internal loading of the joints for each strike pattern. A secondary purpose was to determine if converted FFS and RFS runners can adequately represent habitual runners with regards to the internal joint loading. Using inverse dynamics to calculate the net joint moments and reaction forces and optimization techniques to estimate muscle forces, we determined the axial compressive loading at the ankle, knee, and hip. Subjects consisted of 15 habitual FFS and 15 habitual RFS competitive runners. Each subject ran at a preferred running velocity with their habitual strike pattern and then converted to the opposite strike pattern. Plantar flexor muscle forces and net ankle joint moments were greater in the FFS running compared to the RFS running during the first half of the stance phase. The average contact forces during this period increased by 41.7% at the ankle and 14.4% at the knee joint during FFS running. Peak ankle joint contact force was 1.5 body weights greater during FFS running (p<0.05). There was no evidence to support a difference between habitual and converted running for joint contact forces. The increased loading at the ankle joint for FFS is an area of concern for individuals considering altering their foot strike pattern.     

MORPHOMETRY, HEMATOLOGY, AND SERUM CHEMISTRY IN THE HAWAIIAN MONK SEAL (MONACHUS SCHAUINSLANDI)

We studied morphometric, hematology, and serum chemistry variables in 140 Hawaiian monk seals ( Monachus schauinslandi ) to establish normal baseline values for these variables among free-living seals. We compared seals at French Frigate Shoals (FFS), Midway Atoll (MID), and Pearl and Hermes Reef (PHR) because these subpopulations differ in their rates of population recovery. Dorsal standard length and axillary girth differed significantly between immature (1–4 yr old) and adult (≥5 yr old) seals among sex and island subgroups. Immature seals at FFS were shorter than those at MID and PHR; adult seals at FFS had smaller dorsal standard lengths and axillary girths compared to the other subpopulations. The differences in size were more pronounced among adult females. Significant differences were also found for hematology and serum chemistry variables among seals at FFS, MID, and PHR. Monk seals at FFS had an absolute lymphopenia and eosinopenia compared to those at MID and PHR, compatible with a stress response. Seals at FFS also had lower blood urea nitrogen than seals at PHR, and a lower plasma potassium than seals at MID or PHR. Monk seals had an absolute and relative eosinophilia compared to previously published values. Analysis of subpopulation differences is useful for population health assessment and for long-term monitoring of an endangered species.     

Preventive attitudes,beliefs, and practices of physicians in fee-for-service and health maintenance organization settings.

To identify the self-reported differences in preventive practices, attitudes, and beliefs of physicians practicing in fee-for-service (FFS) and health maintenance organization (HMO) settings, we surveyed a 100% sample of primary care physicians practicing in a large, urban, closed-panel HMO and a random sample of physicians, in the same county, who were in an FFS practice. The FFS physicians were more likely to consider behavioral risk factors important than were HMO physicians, and they were more likely to ask their patients about behavioral risk factors. Fee-for-service physicians were more likely than HMO physicians to use continuing medical education courses to upgrade their skills in modifying behavioral risk factors. There was little difference in the self-reported proportion of patients with specific behavioral risks in the FFS and HMO practices. Also, both groups were comparable in their perception of their ability to do behavioral counseling and their perceived success in such counseling. We conclude that FFS physicians are more likely to have positive preventive beliefs, attitudes, and practices than are HMO physicians.     

Enhancing Anti-Tumor Efficacy of Doxorubicin by Non-Covalent Conjugation to Gold Nanoparticles – In Vitro Studies on Feline Fibrosarcoma Cell Lines

BackgroundFeline injection-site sarcomas are malignant skin tumors of mesenchymal origin, the treatment of which is a challenge for veterinary practitioners. Methods of treatment include radical surgery, radiotherapy and chemotherapy. The most commonly used cytostatic drugs are cyclophosphamide, doxorubicin and vincristine. However, the use of cytostatics as adjunctive treatment is limited due to their adverse side-effects, low biodistribution after intravenous administration and multidrug resistance. Colloid gold nanoparticles are promising drug delivery systems to overcome multidrug resistance, which is a main cause of ineffective chemotherapy treatment. The use of colloid gold nanoparticles as building blocks for drug delivery systems is preferred due to ease of surface functionalization with various molecules, chemical stability and their low toxicity.MethodsStability and structure of the glutathione-stabilized gold nanoparticles non-covalently modified with doxorubicin (Au-GSH-Dox) was confirmed using XPS, TEM, FT-IR, SAXRD and SAXS analyses. MTT assay, Annexin V and Propidium Iodide Apoptosis assay and Rhodamine 123 and Verapamil assay were performed on 4 feline fibrosarcoma cell lines (FFS1WAW, FFS1, FFS3, FFS5). Statistical analyses were performed using Graph Pad Prism 5.0 (USA).ResultsA novel approach, glutathione-stabilized gold nanoparticles (4.3 +/- 1.1 nm in diameter) non-covalently modified with doxorubicin (Au-GSH-Dox) was designed and synthesized. A higher cytotoxic effect (p<0.01) of Au-GSH-Dox than that of free doxorubicin has been observed in 3 (FFS1, FFS3, FFS1WAW) out of 4 feline fibrosarcoma cell lines. The effect has been correlated to the activity of glycoprotein P (main efflux pump responsible for multidrug resistance).ConclusionsThe results indicate that Au-GSH-Dox may be a potent new therapeutic agent to increase the efficacy of the drug by overcoming the resistance to doxorubicin in feline fibrosarcoma cell lines. Moreover, as doxorubicin is non-covalently attached to glutathione coated nanoparticles the synthesized system is potentially suitable to a wealth of different drug molecules.     

Force feasible set prediction with artificial neural network and musculoskeletal model

Abstract

Developing tools to predict the force capabilities of the human limbs through the Force Feasible Set (FFS) may be of great interest for robotic assisted rehabilitation and digital human modelling for ergonomics. Indeed, it could help to refine rehabilitation programs for active participation during exercise therapy and to prevent musculoskeletal disorders. In this framework, the purpose of this study is to use artificial neural networks (ANN) to predict the FFS of the upper-limb based on joint centre Cartesian positions and anthropometric data. Seventeen right upper-limb musculoskeletal models based on individual anthropometric data are created. For each musculoskeletal model, the FFS is computed for 8428 different postures. For any combination of force direction and joint positions, ANNs can predict the FFS with high values of coefficient of determination (R²?>?0.89) between the true and predicted data.     

Foot joint coupling variability differences between habitual rearfoot and forefoot runners prior to and following an exhaustive run

As joint coupling variability has been associated with running-related lower extremity injury, the purpose of this study was to identify how variability within the foot may be different between forefoot (FFS) and rearfoot strike (RFS) runners. Identifying typical variability in uninjured runners may contribute to understanding of ideal coordination associated with running foot strike patterns.Fifteen FFS and 15 RFS runners performed a maximal-effort 5 km treadmill run. A 7-segment foot model identified 6 functional articulations (rearfoot, medial and lateral midfoot and forefoot, and 1st metatarsophalangeal) for analysis. Beginning and end of the run motion capture data were analyzed. Vector coding was used to calculate 6 joint couples. Standard deviations of the coupling angles were used to identify variability within subphases of stance (loading, mid-stance, terminal, and pre-swing). Mixed between-within subjects ANOVAs compared differences between the foot strikes, pre and post run.Increased variability was identified within medial foot coupling for FFS and within lateral foot coupling for RFS during loading and mid-stance. The exhaustive run increased variability during mid-stance for both groups.Interpretation. Joint coupling variability profiles for FFS and RFS runners suggest different foot regions have varying coordination needs which should be considered when comparing the strike patterns.     

Fluorescence fluctuation spectroscopy in the presence of immobile fluorophores

Fluorescence contributions from immobile sources present a challenge for fluorescence fluctuation spectroscopy (FFS) because the absence of signal fluctuations from stationary fluorophores leads to a biased analysis. This is especially of concern for cellular FFS studies on proteins that interact with immobile structures. Here we present a method that correctly analyzes FFS experiments in the presence of immobile sources by exploiting selective photobleaching of immobile fluorophores. The fluorescence decay due to photobleaching of the immobile species is modeled taking into account the nonuniform illumination volume. The experimentally observed decay curve serves to separate the mobile and immobile fluorescence contribution, which is used to calculate the molecular brightness from the FFS data. We experimentally verify this approach in vitro using the fluorescent protein EGFP as our immobilized species and a diffusing dye of a different color as the mobile one. For this special case, we also use an alternative method of determining the brightness by spectrally resolving the two species. By conducting a dilution study, we show that the correct parameters are obtained using either technique for a wide range of mobile fractions. To demonstrate the application of our technique in living cells, we perform experiments using the histone core protein H2B fused with EGFP expressed in COS-1 cells. We successfully recovered the brightness of the mobile fraction of H2B-EGFP.     

The shark assemblage at French Frigate Shoals atoll, Hawai'i: species composition, abundance and habitat use

Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total of 221 sharks from 7 species were captured, among which Galapagos (Carcharhinus galapagensis, 36.2%), gray reef (Carcharhinus amblyrhynchos, 25.8%) and tiger (Galeocerdo cuvier, 20.4%) sharks were numerically dominant. A lack of blacktip reef sharks (Carcharhinus melanopterus) distinguished the FFS shark assemblage from those at many other atolls in the Indo-Pacific. Compared to prior underwater visual survey estimates, longline methods more accurately represented species abundance and composition for the majority of shark species. Sharks were significantly less abundant in the shallow lagoon than adjacent habitats. Recaptures of Galapagos sharks provided the first empirical estimate of population size for any Galapagos shark population. The overall recapture rate was 5.4%. Multiple closed population models were evaluated, with Chao M(h) ranking best in model performance and yielding a population estimate of 668 sharks with 95% confidence intervals ranging from 289-1720. Low shark abundance in the shallow lagoon habitats suggests removal of a small number of sharks from the immediate vicinity of lagoonal islets may reduce short-term predation on endangered monk seal (Monachus schauinslandi) pups, but considerable fishing effort would be required to catch even a small number of sharks. Additional data on long-term movements and habitat use of sharks at FFS are required to better assess the likely ecological impacts of shark culling.     

Foot strike patterns of runners at the 15-km point during an elite-level half marathon

There are various recommendations by many coaches regarding foot landing techniques in distance running that are meant to improve running performance and prevent injuries. Several studies have investigated the kinematic and kinetic differences between rearfoot strike (RFS), midfoot strike (MFS), and forefoot strike (FFS) patterns at foot landing and their effects on running efficiency on a treadmill and over ground conditions. However, little is known about the actual condition of the foot strike pattern during an actual road race at the elite level of competition. The purpose of the present study was to document actual foot strike patterns during a half marathon in which elite international level runners, including Olympians, compete. Four hundred fifteen runners were filmed by 2 120-Hz video cameras in the height of 0.15 m placed at the 15.0-km point and obtained sagittal foot landing and taking off images for 283 runners. Rearfoot strike was observed in 74.9% of all analyzed runners, MFS in 23.7%, and FFS in 1.4%. The percentage of MFS was higher in the faster runners group, when all runners were ranked and divided into 50 runner groups at the 15.0-km point of the competition. In the top 50, which included up to the 69th place runner in actual order who passed the 15-km point at 45 minutes, 53 second (this speed represents 5.45 m x s(-1), or 15 minutes, 17 seconds per 5 km), RFS, MFS, and FFS were 62.0, 36.0, and 2.0%, respectively. Contact time (CT) clearly increased for the slower runners, or the placement order increased (r = 0.71, p < or = 0.05). The CT for RFS + FFS for every 50 runners group significantly increased with increase of the placement order. The CT for RFS was significantly longer than MFS + FFS (200.0 +/- 21.3 vs. 183.0 +/- 16 millisecond). Apparent inversion (INV) of the foot at the foot strike was observed in 42% of all runners. The percentage of INV for MFS was higher than for RFS and FFS (62.5, 32.0, and 50%, respectively). The CT with INV for MFS + FFS was significantly shorter than the CT with and without INV for RFS. Furthermore, the CT with INV was significantly shorter than push-off time without INV for RFS. The findings of this study indicate that foot strike patterns are related to running speed. The percentage of RFS increases with the decreasing of the running speed; conversely, the percentage of MFS increases as the running speed increases. A shorter contact time and a higher frequency of inversion at the foot contact might contribute to higher running economy.     

Fluorescence Fluctuation Spectroscopy of mCherry in Living Cells

The red fluorescent protein mCherry is of considerable interest for fluorescence fluctuation spectroscopy (FFS), because the wide separation in color between mCherry and green fluorescent protein provides excellent conditions for identifying protein interactions inside cells. This two-photon study reveals that mCherry exists in more than a single brightness state. Unbiased analysis of the data needs to account for the presence of multiple states. We introduce a two-state model that successfully describes the brightness and fluctuation amplitude of mCherry. The properties of the two states are characterized by FFS and fluorescence lifetime experiments. No interconversion between the two states was observed over the experimentally probed timescales. The effect of fluorescence resonance energy transfer between enhanced green fluorescent protein (EGFP) and mCherry is incorporated into the two-state model to describe protein hetero-oligomerization. The model is verified by comparing the predicted and measured brightness and fluctuation amplitude of several fusion proteins that contain mCherry and EGFP. In addition, hetero-fluorescence resonance energy transfer between mCherry molecules in different states is detected, but its influence on FFS parameters is small enough to be negligible. Finally, the two-state model is applied to study protein oligomerization in living cells. We demonstrate that the model successfully describes the homodimerization of nuclear receptors. In addition, we resolved a mixture of interacting and noninteracting proteins labeled with EGFP and mCherry. These results provide the foundation for quantitative applications of mCherry in FFS studies.     

Studying the intracellular dissociation of polymer-oligonucleotide complexes by dual color fluorescence fluctuation spectroscopy and confocal imaging

To transfect cells, cationic polymers as well as cationic liposomes are widely investigated as carriers for both oligonucleotides and plasmid DNA. A major step in the successful intracellular delivery of the DNA is the release from its carrier. In this study, dual color fluorescence fluctuation spectroscopy (dual color FFS) was explored in order to characterize the intracellular dissociation of cationic polymer/oligonucleotide complexes. As a model, rhodamine green-labeled oligonucleotides (RhGr-ONs) were complexed with Cy5-labeled polymers of either high molar mass (Cy5-graft-pDMAEMA, 1700 kDa) or low molar mass [Cy5-poly(l-lysine), Cy5-pLL, 30 kDa]. The FFS results were compared with confocal laser scanning microscopy (CLSM) observations. CLSM proved that Cy5-graft-pDMAEMA/RhGr-ON complexes endocytosed by Vero cells dissociate in the cytoplasm: the polymer was only detected in the cytoplasm whereas the (released) RhGr-ONs accumulated in the nucleus. Transfecting Vero cells with Cy5-pLL/RhGr-ON complexes resulted, however, in colocalization of polymer and oligonucleotides in the nucleus. In the latter case, CLSM was not able to prove whether intact Cy5-pLL/RhGr-ON complexes were present in the nucleus or whether both components were located together in the nucleus without being associated. Dual color FFS, which monitors the movement of (dual labeled) fluorescent molecules, was able to answer this question. As a Cy5-pLL/RhGr-ON complex is multimolecular, i.e., it consists of many RhGr-ONs associated with many Cy5-pLL chains, it is both highly green and red fluorescent. Consequently, when Cy5-pLL/RhGr-ON complexes move through the excitation volume, the (green and red) detectors of the FFS instrument detect simultaneously a strong green and red fluorescence peak. Upon transfecting the Vero cells with Cy5-pLL/RhGr-ON complexes, FFS was indeed able to detect simultaneously green and red fluorescence peaks in the cytoplasm but never in the nucleus. From these results we conclude that the Cy5-pLL and RhGr-ONs present in the nucleus after transfection were not associated.     

Characterization of cytoplasmic Gag-gag interactions by dual-color z-scan fluorescence fluctuation spectroscopy

Fluorescence fluctuation spectroscopy (FFS) quantifies the interactions of fluorescently-labeled proteins inside living cells by brightness analysis. However, the study of cytoplasmic proteins that interact with the plasma membrane is challenging with FFS. If the cytoplasmic section is thinner than the axial size of the observation volume, cytoplasmic and membrane-bound proteins are coexcited, which leads to brightness artifacts. This brightness bias, if not recognized, leads to erroneous interpretation of the data. We have overcome this challenge by introducing dual-color z-scan FFS and the addition of a distinctly colored reference protein. Here, we apply this technique to study the cytoplasmic interactions of the Gag proteins from human immunodeficiency virus type 1 (HIV-1) and human T-lymphotropic virus type 1 (HTLV-1). The Gag protein plays a crucial role in the assembly of retroviruses and is found in both membrane and cytoplasm. Dual-color z-scans demonstrate that brightness artifacts are caused by a dim nonpunctate membrane-bound fraction of Gag. We perform an unbiased brightness characterization of cytoplasmic Gag by avoiding the membrane-bound fraction and reveal previously unknown differences in the behavior of the two retroviral Gag species. HIV-1 Gag exhibits concentration-dependent oligomerization in the cytoplasm, whereas HTLV-1 Gag lacks significant cytoplasmic Gag-Gag interactions.     

Estimating the carrying capacity of French Frigate Shoals for the endangered Hawaiian monk seal using Ecopath with Ecosim

The carrying capacity of the French Frigate Shoals (FFS) region for the endangered Hawaiian monk seal was appraised using an updated version of the original FFS Ecopath model ( Polovina 1984 ). Model parameters were updated using recent literature, and data from surveys of the seal population and its bottom‐associated prey. Together they produced a static mass balance model for 1998 when the prey surveys began. The Ecopath‐estimated monk seal biomass was 0.0045 t/km², which was in close agreement with the biomass calculated from monk seal field beach counts (0.0046 t/km²). Model simulations through time were done in Ecosim using the Ecopath balanced model and included fisheries data time series from 1998 to 2008. Monk seal biomass declined concurrently with decreases in benthic bottomfish biomass, which were influenced by large‐scale changes in the environment of the North Pacific. This model scenario was extended from 2010, when the last permitted fishery in the Northwestern Hawaiian Islands was closed, through to 2040, assuming a constant environmental signal. Model results for this time period did not show a recovery of monk seals that exceeded the initial 1998 model biomass levels, highlighting the importance of including environmental variability in estimates of monk seals recovery at FFS.     

Ergebnisse aus vergleichenden untersuchungen von parametern der pansenfermentation und zur verdaulichkeit von futterrationen bei rind und schaf

Die Ergebnisse von 283 Untersuchungen des mittels Schlundsonde gewonnenen Pansensaftes der Tierarten Rind (Ochse, Kuh, männliches und weibliches Jungrind) und Schaf (adulte Hammel) werden verglichen. Die untersuchten Parameter sind: Anteile an flüchtigen Fettsäuren (FFS), Gesamtgehalt an FFS, pH‐Wert, NH₃‐ und Harnstoffgehalt. Der Essigsäureanteil liegt beim Rind im Mittel um 2 Mol‐% und der Gesamtgehalt an FFS bis zu 28 mmol/1 (Mittelwert für die Kuh‐Schaf‐Vergleiche) höher als beim Hammel. Die NH₃‐ und Harnstoffgehalte sind bei allen Kategorien des Rindes niedriger als beim Hammel. Beziehungen zwischen der Höhe der Differenz der Parameter bei Rind und Schaf und dem Rohfasergehalt der Rationen, der Lebendmasse der Jungrinder und dem Ernährungsniveau werden verfolgt.