5,155 research outputs found
Temptation and self-control: some evidence and applications
This paper studies the empirical relevance of temptation and self-control using household-level data from the Consumer Expenditure Survey. We estimate an infinite-horizon consumption-savings model that allows, but does not require, temptation and self-control in preferences. To help identify the presence of temptation, we exploit an implication of the theory that a tempted individual has a preference for commitment. In the presence of temptation, the cross-sectional distribution of the wealth-consumption ratio, in addition to that of consumption growth, becomes a determinant of the asset-pricing kernel, and the importance of this additional pricing factor depends on the strength of temptation. The estimates that we obtain provide statistical evidence supporting the presence of temptation. Based on our estimates, we explore some quantitative implications of this class of preferences on equity premium and on the welfare cost of business cycles.Asset pricing ; Welfare
Possible effects of probiotic strains on suppression of Vibrio and enhancement of growth in rotifer, Brachionus plicatilis
Because of the importance of rotifers as an adequate live food in larviculture, this study was conducted to evaluate probiotic potency of four microorganisms, Candida parapsilosis, Pseudoalteromonas flavipulchra, Lactobacillus sakei and Bacillus natto on suppression of Vibrio species and increasing population growth, enzymes activity and nutrients retention in the rotifer, Brachionus plicatilis. Four experimental and a control treatment, each with four replicates, with the concentration of 10(8) CFU/mL(-)(1) for each strain were applied. The results demonstrated that L. sakei and B. natto successfully suppressed Vibrio in experimental treatments and increased population growth and nutrients retention. The longevity of B. natto was recorded as the best in long-term inoculation than other treatments and the control in a way that after 8 days of rotifers starvation, the count of B. natto increased. The findings showed that the two bacteria, B. natto and L. sakei, appear to be a promising probiotic for rotifers in suppressing Vibrio and also in increasing population growth, nutrients retention, enzymes activity and long-term inoculation in rotifers
KGFR promotes Na+ channel expression in a rat acute lung injury model
Background: Binding of keratinocyte growth factor (KGF) to the KGF receptor (KGFR) plays an important role in the recovery of alveolar epithelial cells from acute lung injury (ALI).Objectives: To evaluate the effect of gene therapy via adenovirus gene transfer of KGFR on the treatment of ALI.Methods: Sprague–Dawley rats were divided into four groups: normal controls, injury controls, normal adenovirus transduced group and injury adenovirus transduced group. The ALI model was induced by lipopolysaccharide (LPS) injection. Recombinant adenovirus (AdEasy-KGFR) was injected via the tail vein. Expression of the sodium (Na+) channel in rat alveolar type II (ATII) epithelial cells was determined by PCR, immunohistochemistry and immunoelectron microscopy of rat lung tissues.Results: Gene expression of the Na+ channel and KGFR in ATII cells was higher in the normal adenovirus transduced group than the three other groups; expression of these two genes in the injury adenovirus transduced group was higher than the injury control group. Na+ channel protein expression was lower in the injury adenovirus transduced group but higher than the injury control group.Conclusions: KGFR over-expression induced Na channel expression could potentially be beneficial for ALI therapy.Keywords: Keratinocyte growth factor-receptor (KGFR); sodium (Na+) channel; rat model;acute lung injury (ALI); gene therap
Emerging and reemerging helminthiases and the public health of China.
Despite great strides in their control throughout the People's Republic of China, helminth infections remain an important public health problem. The Institute of Parasitic Diseases of the Chinese Academy of Preventive Medicine, under the guidance of the Chinese Ministry of Health, completed a nationwide survey of more than 1 million people that showed the high prevalence and intensity of intestinal nematode infections; prevalence can sometimes exceed 50% in the Yangtze River valley provinces. Schistosoma japonicum is also a major cause of illness in this region. Attempts to control Chinese helminthic diseases with conventional anthelminthic drugs have been partially thwarted by high posttreatment rates of reinfection. Recently, several new human trematode pathogens have been identified. Novel approaches to chemoprophylaxis and vaccination may alleviate the public health problem caused by Chinese helminths. However, recombinant helminth vaccine development will depend on first cataloguing the extensive genetic diversity of Chinese helminths and candidate vaccine antigens. Evidence from biogeography, genetics, and systematics suggests that the genetic diversification of Chinese helminths and their vectors is an ongoing evolutionary process that began 12 million years ago near the convergence of major Asian river systems. Construction of the Three Gorges Super Dam on the Yangtze River may promote the emergence and reemergence of new helminths and their snail vector
Selective activation of four quasi-equivalent C-H bonds yields N-doped graphene nanoribbons with partial corannulene motifs
Selective C–H bond activation is one of the most challenging topics for organic reactions. The difficulties arise not only from the high C–H bond dissociation enthalpies but also the existence of multiple equivalent/quasi-equivalent reaction sites in organic molecules. Here, we successfully achieve the selective activation of four quasi-equivalent C–H bonds in a specially designed nitrogen-containing polycyclic hydrocarbon (N-PH). Density functional theory calculations reveal that the adsorption of N-PH on Ag(100) differentiates the activity of the four ortho C(sp3) atoms in the N-heterocycles into two groups, suggesting a selective dehydrogenation, which is demonstrated by sequential-annealing experiments of N-PH/Ag(100). Further annealing leads to the formation of N-doped graphene nanoribbons with partial corannulene motifs, realized by the C–H bond activation process. Our work provides a route of designing precursor molecules with ortho C(sp3) atom in an N-heterocycle to realize surface-induced selective dehydrogenation in quasi-equivalent sites
Spin-Rotation Symmetry Breaking in the Superconducting State of CuxBi2Se3
Spontaneous symmetry breaking is an important concept for understanding
physics ranging from the elementary particles to states of matter. For example,
the superconducting state breaks global gauge symmetry, and unconventional
superconductors can break additional symmetries. In particular, spin rotational
symmetry is expected to be broken in spin-triplet superconductors. However,
experimental evidence for such symmetry breaking has not been conclusively
obtained so far in any candidate compounds. Here, by 77Se nuclear magnetic
resonance measurements, we show that spin rotation symmetry is spontaneously
broken in the hexagonal plane of the electron-doped topological insulator
Cu0.3Bi2Se3 below the superconducting transition temperature Tc=3.4 K. Our
results not only establish spin-triplet superconductivity in this compound, but
may also serve to lay a foundation for the research of topological
superconductivity
- …