The Norwegian dairy goat population has a high frequency of a CSN1S1 (αS1-casein) haplotype with negative effects on protein and fat content. It is characterized by a single point deletion in exon 12 of CSN1S1, leading to a truncated protein and hence a low content of αS1-casein in the milk. This haplotype together with another haplotype with a deletion in exon 9 are called “weak” haplotypes. “Strong” haplotypes, on the other hand, have positive effects on important milk production traits. We show that expression of CSN1S1 in the mammary gland of lactating goats is significantly lower in animals with 2 weak haplotypes. Moreover, the effects of defective alleles were not detected in animals having 1 strong and 1 weak haplotype. Expression levels of other genes in the casein cluster were not affected by the CSN1S1 haplotypes investigated. Milk samples from goats with 2 weak haplotypes could be distinguished from the other milk samples using Fourier transform infrared (FTIR) spectroscopy and partial least squares discriminant analysis (PLS-DA). The PLS-DA components were related to spectra of pure caseins and whey proteins, hence FTIR has a potential for identifying milk samples with low αS1-casein content and different protein composition. The results indicate that FTIR-based measurements can be incorporated into breeding plans, or for selection of milk samples with high casein content, which in turn may improve cheese-making properties of the milk. 相似文献
Previous research demonstrates the importance of goal orientation, leader-leader exchange, and trust in work engagement and performance. However, how the relationships among these three variables influence project performance remains unclear. Complementing and extending prior research, this study uncovers how leader-leader exchange and trust affect the relationship between goal orientations and project performance. A cross-sectional analysis of 320 auditing project managers from 50 financial service companies shows that leader-leader exchange and trust mediate how goal orientations influence project performance. We also find that trust further moderates the effect of leader-leader exchange on project performance. Subsequent quantitative analysis of structural equation modeling reveals that leader-leader exchange has the largest direct effect on project performance; team-mastery goal orientation has the second-largest direct effect but the largest total effect. Implications for research and practice are discussed. 相似文献
Assembly is the capstone process for product realization where component parts and subassemblies are integrated together to form the final products. As product variety increases due to the shift from mass production to mass customization, assembly systems must be designed and operated to handle such high variety. In this paper we first review the state of the art research in the areas of assembly system design, planning and operations in the presence of product variety. Methods for assembly representation, sequence generation and assembly line balancing are reviewed and summarized. Operational complexity and the role of human operators in assembly systems are then discussed in the context of product variety. Challenges in disassembly and remanufacturing in the presence of high variety are presented. We then conjecture a future manufacturing paradigm of personalized products and production and discuss the assembly challenge for such a paradigm. Opportunities for assembly system research are summarized at the end of the paper. 相似文献
Parkinson's disease is characterised by a variable combination of tremor, rigidity, bradykinesia and impaired righting reflexes. The cumulative life-time risk is one in 40. Levodopa remains the single most effective treatment in older patients, and the minimum dose to achieve maximum functional benefit should be employed. When fluctuations occur, controlled release preparations and selegiline can improve function. Oral dopamine agonists have a role but the combined side effect profile with levodopa should be monitored. COMT inhibitors have recently become available. Subcutaneous apomorphine can be helpful when "on-off" phenomena are marked. The concept of neuroprotection continues to be debated. Surgery is an option for fitter older people but neurotransplantation remains essentially a research tool. 相似文献
This study developed an innovative gas-assisted microstructure elastic multiform UV imprint replication molding technology. It first designed and fabricated the upper closed gas chamber and lower four-directional extension open imprint chamber system. Then, ANSYS software was used to analyze the axial stress uniformity of the multiaxial extension of the flexible mold and design the extension angle. A gas-assisted elastic multiaxial UV imprinting system was designed. The imprint uniformity and stability were tested and discussed by gas-assisted pressing and pressure sensitive adhesive tape. After regulation and control of elastic multiform variation of the lower chamber, the four-axis microstructure component transfer printing was tested. The experimental results showed that the imprinting system proposed in this study effectively controls the imprint mold shape in the elastic range with the flexible mold, and the gas-assisted uniform pressing transfer printing replication proves that excellent complementary structures of imprint replication can be obtained. This process technology greatly reduces the time and energy consumption of microelectromechanical process, providing a faster and economical option.
We study the spatial distribution of the temperature, gain, and carrier density along the longitudinal direction of a semiconductor laser cavity. In high-power laser diodes, the use of asymmetrical facet reflectivities creates a spatially nonuniform photon intensity profile and results in inhomogeneous temperature and carrier distributions along the active stripe. These profiles are determined from direct measurements of blackbody radiation and the spontaneous emission from the laser cavity. The temperature of the active stripe is observed to be significantly higher than that of the heat sink during lasing, and the effect of temperature on the modal gain spectrum is analyzed. We demonstrate that the local carrier density and optical gain within a laser are not pinned beyond threshold. A spatially inhomogeneous gain profile is possible in laser cavities as long as the threshold condition that the averaged round-trip gain equals the total losses is maintained. A theoretical model is presented which explains the observed experimental data 相似文献
In this paper, we wish to point out that the proof of the main results in the above-mentioned paper by Lee (ibid. vol.40 (1995)) is incorrect. Furthermore, we verify that there exists no continuous time-delay system guaranteeing the D(α, r)-stability 相似文献