885 research outputs found
A Multi-Task Theory of the State Enterprise Reform
During transition, maintaining employment and providing a social safety net to the unemployed are important to social stability, which in turn is crucial for the productivity of the whole economy. Because independent institutions for social safety are lacking and firms with strong profit incentives have little incentives to promote social stability due to its public good nature, state-owned enterprises (SOEs) are needed to continue their role in providing social welfare. Charged with the multi-tasks of efficient production as well as social welfare provision, SOEs continue to be given low profit incentives and consequently, their financial performance continues to be poor.http://deepblue.lib.umich.edu/bitstream/2027.42/39751/3/wp367.pd
A linear-time algorithm for reconstructing zero-recombinant haplotype configuration on a pedigree
BACKGROUND: When studying genetic diseases in which genetic variations are passed on to offspring, the ability to distinguish between paternal and maternal alleles is essential. Determining haplotypes from genotype data is called haplotype inference. Most existing computational algorithms for haplotype inference have been designed to use genotype data collected from individuals in the form of a pedigree. A haplotype is regarded as a hereditary unit and therefore input pedigrees are preferred that are free of mutational events and have a minimum number of genetic recombinational events. These ideas motivated the zero-recombinant haplotype configuration (ZRHC) problem, which strictly follows the Mendelian law of inheritance, namely that one haplotype of each child is inherited from the father and the other haplotype is inherited from the mother, both without any mutation. So far no linear-time algorithm for ZRHC has been proposed for general pedigrees, even though the number of mating loops in a human pedigree is usually very small and can be regarded as constant. RESULTS: Given a pedigree with n individuals, m marker loci, and k mating loops, we proposed an algorithm that can provide a general solution to the zero-recombinant haplotype configuration problem in O(kmn + k(2)m) time. In addition, this algorithm can be modified to detect inconsistencies within the genotype data without loss of efficiency. The proposed algorithm was subject to 12000 experiments to verify its performance using different (n, m) combinations. The value of k was uniformly distributed between zero and six throughout all experiments. The experimental results show a great linearity in terms of execution time in relation to input size when both n and m are larger than 100. For those experiments where n or m are less than 100, the proposed algorithm runs very fast, in thousandth to hundredth of a second, on a personal desktop computer. CONCLUSIONS: We have developed the first deterministic linear-time algorithm for the zero-recombinant haplotype configuration problem. Our experimental results demonstrated the linearity of its execution time in relation to the input size. The proposed algorithm can be modified to detect inconsistency within the genotype data without loss of efficiency and is expected to be able to handle recombinant and missing data with further extension
Stability of Sb line structures on Si(001)
Structure and stability of Sb-dimer linear chains on the Si(001) surface are studied by means of ab initio quantum-mechanical molecular dynamics using pseudopotentials. It is confirmed that the model comprising a double core of seven-membered rings of silicon for Bi/Si(001) nanolines is indeed one of the most stable structures energetically, and it also explains Sb/Si nanolines. Moreover, it is clear that stability of the odd-membered-ring (5-7-5) structure will decrease as the group-V adatom changes from Bi to Sb, and disappear for As/Si due to the size effect
Diversity and structure of soil bacterial communities in the Fildes Region (maritime Antarctica) as revealed by 454 pyrosequencing
This study assessed the diversity and composition of bacterial communities in four different soils (human-, penguin-, seal-colony impacted soils and pristine soil) in the Fildes Region (King George Island, Antarctica) using 454 pyrosequencing with bacterial-specific primers targeting the 16S rRNA gene. Proteobacteria, Actinobacteria, Acidobacteria, and Verrucomicrobia were abundant phyla in almost all the soil samples. The four types of soils were significantly different in geochemical properties and bacterial community structure. Thermotogae, Cyanobacteria, Fibrobacteres, Deinococcus-Thermus, and Chlorobi obviously varied in their abundance among the 4 soil types. Considering all the samples together, members of the genera Gaiella, Chloracidobacterium, Nitrospira, Polaromonas, Gemmatimonas, Sphingomonas and Chthoniobacter were found to predominate, whereas members of the genera Chamaesiphon, Herbaspirillum, Hirschia, Nevskia, Nitrosococcus, Rhodococcus, Rhodomicrobium, and Xanthomonas varied obviously in their abundance among the four soil types. Distance-based redundancy analysis revealed that pH (p < 0.01), phosphate phosphorus (p < 0.01), organic carbon (p < 0.05), and organic nitrogen (p < 0.05) were the most significant factors that correlated with the community distribution of soil bacteria. To our knowledge, this is the first study to explore the soil bacterial communities in human-, penguin-, and seal- colony impacted soils from ice-free areas in maritime Antarctica using high-throughput pyrosequencing
Theoretical study of the open-flavor tetraquark in the process
Recently, the LHCb Collaboration has measured the processes
and , where the
and invariant mass distributions show the significant
signals of two new open-flavor tetraquark states and
, as the two of the isospin triplet. In this work, we
have investigated the process by taking into
account the intermediate nucleon resonance and the tetraquark state
, which could be dynamically generated by the
interactions of the and the pseoduscalar mesons-octet
baryons, respectively. Our results show that a clear peak of the open-flavor
tetraquark may appear in the invariant mass
distribution of the process , which could be tested
by future experiments.Comment: 9 pages, 11 figures, 1 tabl
Single nonmagnetic impurity resonance in FeSe-based 122-type superconductors as a probe for pairing symmetry
We study the effect of a single non-magnetic impurity in
AFeSe (A=K, Rb, or Cs) superconductors by considering
various pairing states based on a three-orbital model consistent with the
photoemission experiments. The local density of states on and near the impurity
site has been calculated by solving the Bogoliubov-de Gennes equations
self-consistently. The impurity-induced in-gap bound states are found only for
attractive impurity scattering potential, as in the cases of doping of Co or
Ni, which is characterized by the strong particle-hole asymmetry, in the
nodeless wave pairing state. This property may be used to probe
the pairing symmetry of FeSe-based 122-type superconductors.Comment: 7 pages, 7 figure
Connexin 43 recruits E-cadherin expression and inhibits the malignant behaviour of lung cancer cells.
The interaction of connexin 43 and E-cadherin may play an important role in carcinogenesis and malignant behaviour of tumours. In this study, we examined the relationship between connexin 43 and E-cadherin in human non-small cell lung cancers (NSCLC). Expression levels of connexin 43 and E-cadherin were examined in 107 NSCLC specimens by immunohistochemistry. The connexin 43 gene was transfected into lung cancer LH7 cells. The protein localizations and levels of connexin 43 and E-cadherin were detected using immunofluorescence staining and western blot. Cell cycle and proliferation of lung cancer cells were examined using flow cytometry and MTT. We found that reduced expression of both connexin 43 and E-cadherin significantly correlated to poor differentiation, advanced TNM stage, and lymph note metastasis of NSCLCs. Connexin 43 and E-cadherin expression significantly correlated with each other. Over-expression of connexin 43 significantly induced E-cadherin expression. Moreover, connexin 43-transfected LH7 cells showed significantly decreased cell proliferation. The percentage of cells in G1 phase increased, while the number of cells in S and G2 phases significantly decreased. We concluded that concurrent reduction of connexin 43 and E-cadherin may contribute to the development of lung cancer. Connexin 43 may induce E-cadherin expression and inhibit cell proliferation and progression of lung cancer
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