Productivity improvement in Korean rice farming: parametric and non-parametric analysis

The published empirical literature on frontier production functions is dominated by two broadly defined estimation approaches – parametric and non‐parametric. Using panel data on Korean rice production, parametric and non‐parametric production frontiers are estimated and compared with estimated productivity. The non‐parametric approach employs two alternative measures based on the Malmquist index and the Luenberger indicator, while the parametric approach is closely related to the time‐variant efficiency model. Productivity measures differ considerably between these approaches. It is discovered that measures of efficiency change are more sensitive to the choice of the model than are measures of technical change. Both approaches reveal that the main sources of growth in Korean rice farming have been technical change and productivity improvements in regions of the country that have been associated with low efficiency.Crop Production/Industries, Productivity Analysis,

Ultrahigh areal number density solid-state on-chip microsupercapacitors via electrohydrodynamic jet printing

Microsupercapacitors (MSCs) have garnered considerable attention as a promising power source for microelectronics and miniaturized portable/wearable devices. However, their practical application has been hindered by the manufacturing complexity and dimensional limits. Here, we develop a new class of ultrahigh areal number density solid-state MSCs (UHD SS-MSCs) on a chip via electrohydrodynamic (EHD) jet printing. This is, to the best of our knowledge, the first study to exploit EHD jet printing in the MSCs. The activated carbon-based electrode inks are EHD jet-printed, creating interdigitated electrodes with fine feature sizes. Subsequently, a drying-free, ultraviolet-cured solid-state gel electrolyte is introduced to ensure electrochemical isolation between the SS-MSCs, enabling dense SS-MSC integration with on-demand (in-series/in-parallel) cell connection on a chip. The resulting on-chip UHD SS-MSCs exhibit exceptional areal number density [36 unit cells integrated on a chip (area = 8.0 mm x 8.2 mm), 54.9 cells cm(-2)] and areal operating voltage (65.9 V cm(-2))

High energy-charged cell factory for heterologous protein synthesis

Overexpression of gluconeogenic phosphoenolpyruvate carboxykinase (PCK) under glycolytic conditions enables Escherichia coli to maintain a greater intracellular ATP concentration and, consequently, to up-regulate genes for amino acid and nucleotide biosynthesis. To investigate the effect of a high intracellular ATP concentration on heterologous protein synthesis, we studied the expression of a foreign gene product, enhanced green fluorescence protein (eGFP), under control of the T7 promoter in E. coli BL21(DE3) strain overexpressing PCK. This strain was able to maintain twice as much intracellular ATP and to express two times more foreign protein than the control strain. These results indicate that a high energy-charged cell can be beneficial as a protein-synthesizing cell factory. The potential uses of such a cell factory are discussed

Fishbone-Associated Actinomycosis of the Anterior Cervical Space: A Diagnostic Dilemma

We report the imaging and pathologic findings of fishbone-associated actinomycosis of the anterior cervical space in a 57-year-old man, misdiagnosed preoperatively as a malignancy originating from thyroglossal duct cyst. CT revealed an enhancing mass containing a small abscess pocket and two sharp linear calcifications within it, which infiltrated into the strap muscle. Pathologic examination demonstrated two fishbones within the actinomycotic abscess. Fishbone-associated actinomycosis should be considered when a cervical mass contains sharp linear calcifications

Sliced Wigner Fourth Order Moment Spectra Smoothed by γ

The research proposes a method for detecting valve system faults in an engine. The methodology is based on the detection of impulsive sound embedded in the high level of background noise by using the sliced Wigner fourth order moment spectra (SWFOMS) which is inherently more robust in the presence of random (Gaussian) noise. However, in previous work, the SWFOMS for multiple signals had problems with its application which were due to the existence of non-oscillating cross-terms not smoothed by conventional methods. In this paper, the γ-method is developed to smooth non-oscillation cross-terms. Finally, the techniques developed are applied to the diagnosis of valve system faults in an engine

Economic and environmental equity in the U.S. nonmetropolitan tourism and recreation dependent communities

This study focused on economic and environmental equity in tourism and recreation dependent communities in the U. S. In the economic equity section, research was conducted to do an empirical analysis of the income distribution in nonmetropolitan tourism and recreation dependent communities. In the environmental equity section, this study evaluated conceptual and theoretical understanding dealing with tourism and the environment and addressed the importance of environmental equity issues. A key objective of this study is to examine economic equity across different income groups and race in nonmetropolitan tourism and recreation dependent communities. By comparing economic equity between nonmetropolitan tourism and recreation dependent communities and other industry dependent nonmetropolitan communities, the differences of income inequality between those communities were explored. This study also assesses how tourism and recreation development contributes to economic equity in nonmetropolitan tourism and recreation communities in the U. S. In particular, determinants of income inequality were investigated. Income distribution of nonmetropolitan tourism and recreation dependent communities is more unequal than that of nonmetropolitan manufacturing dependent communities in the U. S. Tourism and recreation development contributes to increase income inequality while manufacturing related development is likely to reduce income inequality. The positive effect comes from the inequality of earnings in tourism and recreation employment. Race dualism shows a positive relationship with income inequality. This result suggests that the racial difference in income distribution plays an important role in increasing income inequality. There is a positive relationship between the south region and income inequality irrespective of community type and suggest that the regional variable is still an essential component for understanding income inequality in the U.S. This study addresses the need of an environmental justice framework for improving environmental equity across stakeholders in the process of tourism and recreation planning and development. Equity within/between social groups and inter and intra-generational equity should be taken into account for sustainable tourism and recreation development. The analytical framework for assessing environmental equity that this study suggested will be a good foundation for further development of environmental equity framework in the context with tourism and recreation development