bluuebunny/crossref_metadata_2025_split huggingface dataset:
Solution to the Dilemma of the Migrant Labor Shortage and the Rural Labor Surplus in China
Authors: Chen Guifu , Hamori Shigeyuki 
Published: July 2009

AbstractSince 2003, China's labor market has been facing two coexisting crises: a rural labor surplus and a severe shortage of migrant labor. Using data from the 2000 China Health and Nutrition Survey questionnaire, which covers 288 villages in 36 counties, this paper attempts to find a solution to this dilemma. Specifically, a multinomial logit model, a Mincer‐type model and a probit model are applied to examine the effect of educational level on the employment choices for rural laborers, and on the wages and the employment status of migrants. Based on the results of our analysis, we propose the implementation of policy aimed at increasing the educational level of rural dwellers, in conjunction with other policies to eliminate all artificial barriers, to facilitate the migration of rural laborers.
Budget Structure and Pollution Control: A Cross‐country Analysis and Implications for China
Authors: Zhang Li , Zheng Xinye 
Published: July 2009

AbstractIn the published literature, the differences in environmental performance across countries are typically explained using the Environmental Kuznets Curve. The Environmental Kuznets Curve states that pollution initially increases with economic growth. Once GDP per capita reaches a certain level, the relationship reverses. In the present paper, we provide an alternative hypothesis, where budget structure plays an important role in explaining the variations in pollution across the world: the lower the business‐related taxes as a share of total tax revenue, the higher the property tax in total tax revenue and the higher the ratio of public health expenditure in total expenditure, then the stronger the incentive of pollution control and the lower the pollution level. Our empirical findings reveal that the budget structure does have an important impact on pollution control. The policy implication of this research is that effective control of environmental pollution requires changes in tax structure and expenditure assignment. This research has important policy implications for China's tax system reform and pollution control efforts.
Intermediary ecosystem metabolism as a main driver of methanogenesis in acidic wetland soil
Authors: Drake Harold L. , Horn Marcus A. , Wüst Pia K. 
Published: July 2009

SummaryMethanogens have a very limited substrate range, and their in situ activities are thus linked to ‘intermediary ecosystem metabolism’, i.e. complex trophic interactions with other microorganisms catalysing essential intermediary processes that ultimately drive methanogenesis. However, information on intermediary ecosystem metabolism and associated biota is fragmented and often conceptualized rather than resolved. The main objective of this review is to evaluate the concept of intermediary ecosystem metabolism in context with recent work aimed at resolving the complex trophic interactions of a methane‐emitting peatland.
New Treatment Option for Second-Stage African Sleeping Sickness: In Vitro and In Vivo Efficacy of Aza Analogs of DB289
Authors: Wenzler Tanja , Boykin David W. , Ismail Mohamed A. , Hall James Edwin , Tidwell Richard R. , Brun Reto 
Published: July 2009

ABSTRACT

African sleeping sickness is a fatal parasitic disease, and all drugs currently in use for treatment have strong liabilities. It is essential to find new, effective, and less toxic drugs, ideally with oral application, to control the disease. In this study, the aromatic diamidine DB75 (furamidine) and two aza analogs, DB820 and DB829 (CPD-0801), as well as their methoxyamidine prodrugs and amidoxime metabolites, were evaluated against African trypanosomes. The active parent diamidines showed similar in vitro profiles against different
Trypanosoma brucei
strains, melarsoprol- and pentamidine-resistant lines, and a P2 transporter knockout strain (AT1KO), with DB75 as the most trypanocidal molecule. In the
T. b. rhodesiense
strain STIB900 acute mouse model, the aza analogs DB820 and DB829 demonstrated activities superior to that of DB75. The aza prodrugs DB844 and DB868, as well as two metabolites of DB844, were orally more potent in the
T. b. brucei
strain GVR35 mouse central nervous system (CNS) model than DB289 (pafuramidine maleate). Unexpectedly, the parent diamidine DB829 showed high activity in the mouse CNS model by the intraperitoneal route. In conclusion, DB868 with oral and DB829 with parenteral application are potential candidates for further development of a second-stage African sleeping sickness drug.
Activity of Telavancin against Staphylococci and Enterococci Determined by MIC and Resistance Selection Studies
Authors: Kosowska-Shick Klaudia , Clark Catherine , Pankuch Glenn A. , McGhee Pamela , Dewasse Bonifacio , Beachel Linda , Appelbaum Peter C. 
Published: July 2009

ABSTRACTThis study used CLSI broth microdilution to test the activity of telavancin and comparator antimicrobial agents against 67 methicillin (meticillin)-resistantStaphylococcus aureus(MRSA) isolates. Twenty-six vancomycin-intermediateS. aureus(VISA) strains were among the isolates tested; all strains were susceptible to telavancin at ≤1 μg/ml, whereas 12/26 (46%) of these isolates were nonsusceptible to daptomycin at the same concentration. All strains were susceptible to quinupristin-dalfopristin, while resistance was found to all other drugs tested. Telavancin demonstrated potent activity against all vancomycin-susceptible isolates as well as against heterogeneously VISA and VISA resistance phenotypes. In multistep resistance selection studies, telavancin yielded one stable mutant after 43 days in one MRSA strain out of the 10 MRSA strains tested with the MIC rising eightfold from 0.25 μg/ml (parent) to 2 μg/ml. MICs for this clone did not increase further when passages were continued for the maximum 50 days. In contrast, daptomycin selected stable resistant clones (MIC increase of >4×) after 14 to 35 days in 4 of 10 MRSA strains with MICs increasing from 1 to 2 μg/ml (parents) to 4 to 8 μg/ml (resistant clones). Sequencing analysis of daptomycin resistance determinants revealed point mutations in themprFgenes of all four stable daptomycin-resistant clones. Teicoplanin gave rise to resistant clones after 14 to 21 days in 2 of 10 MRSA strains with MICs rising from 1 to 2 μg/ml (parents) to 4 to 16 μg/ml (stable resistant clones). Linezolid selected stable resistant clones after 22 to 48 days in 2 of 10 MRSA strains with MICs rising from 2 to 4 μg/ml (parents) to 32 μg/ml (resistant clones). Vancomycin yielded no resistant clones in 10 MRSA strains tested; however, MICs increased two- to fourfold from 1 to 8 μg/ml to 2 to 16 μg/ml after 50 days. No cross-resistance was found with any clone/antimicrobial combination. The two enterococci developed resistance to daptomycin, and one developed resistance to linezolid. Single-step mutation frequencies for telavancin (<4.0 × 10−11to <2.9 × 10−10at 2× MIC) were lower than the spontaneous mutation frequencies obtained with the comparators.
Dosing Regimens of Cotrimoxazole (Trimethoprim-Sulfamethoxazole) for Melioidosis
Authors: Cheng Allen C. , McBryde Emma S. , Wuthiekanun Vanaporn , Chierakul Wirongrong , Amornchai Premjit , Day Nicholas P. J. , White Nicholas J. , Peacock Sharon J. 
Published: July 2009

ABSTRACT

Melioidosis is an infectious disease with a propensity for relapse, despite prolonged antibiotic eradication therapy for 12 to 20 weeks. A pharmacokinetic (PK) simulation study was performed to determine the optimal dosing of cotrimoxazole (trimethoprim-sulfamethoxazole [TMP-SMX]) used in current eradication regimens in Thailand and Australia. Data for bioavailability, protein binding, and coefficients of absorption and elimination were taken from published literature. Apparent volumes of distribution were correlated with body mass and were estimated separately for Thai and Australian populations. In vitro experiments demonstrated concentration-dependent killing. In Australia, the currently used eradication regimen (320 [TMP]/1,600 [SMX] mg every 12 h [q12h]) was predicted to achieve the PK-pharmacodynamic (PD) target (an area under the concentration-time curve from 0 to 24 h/MIC ratio of >25 for both TMP and SMX) for strains with the MIC
90
of Australian strains (≤1/19 mg/liter). In Thailand, the former regimen of 160/800 mg q12h would not be expected to attain the target for strains with an MIC of ≥1/19 mg/liter, but the recently implemented weight-based regimen (<40 kg [body weight], 160/800 mg q12h; 40 to 60 kg, 240/1,200 mg q12h; >60 kg, 320/1,600 mg q12h) would be expected to achieve adequate concentrations for strains with an MIC of ≤1/19 mg/liter. The results were sensitive to the variance of the PK parameters. Prospective PK-PD studies of Asian populations are needed to optimize TMP-SMX dosing in melioidosis.
NontypeableHaemophilus influenzaeClearance by Alveolar Macrophages Is Impaired by Exposure to Cigarette Smoke
Authors: Martí-Lliteras Pau , Regueiro Verónica , Morey Pau , Hood Derek W. , Saus Carles , Sauleda Jaume , Agustí Alvar G. N. , Bengoechea José Antonio , Garmendia Junkal 
Published: July 2009

ABSTRACTNontypeableHaemophilus influenzae(NTHI) is an opportunistic gram-negative pathogen that causes respiratory infections and is associated with progression of respiratory diseases. Cigarette smoke is a main risk factor for development of respiratory infections and chronic respiratory diseases. Glucocorticoids, which are anti-inflammatory drugs, are still the most common therapy for these diseases. Alveolar macrophages are professional phagocytes that reside in the lung and are responsible for clearing infections by the action of their phagolysosomal machinery and promotion of local inflammation. In this study, we dissected the interaction between NTHI and alveolar macrophages and the effect of cigarette smoke on this interaction. We showed that alveolar macrophages clear NTHI infections by adhesion, phagocytosis, and phagolysosomal processing of the pathogen. Bacterial uptake requires host actin polymerization, the integrity of plasma membrane lipid rafts, and activation of the phosphatidylinositol 3-kinase (PI3K) signaling cascade. Parallel to bacterial clearance, macrophages secrete tumor necrosis factor alpha (TNF-α) upon NTHI infection. In contrast, exposure to cigarette smoke extract (CSE) impaired alveolar macrophage phagocytosis, although NTHI-induced TNF-α secretion was not abrogated. Mechanistically, our data showed that CSE reduced PI3K signaling activation triggered by NTHI. Treatment of CSE-exposed cells with the glucocorticoid dexamethasone reduced the amount of TNF-α secreted upon NTHI infection but did not compensate for CSE-dependent phagocytic impairment. The deleterious effect of cigarette smoke was observed in macrophage cell lines and in human alveolar macrophages obtained from smokers and from patients with chronic obstructive pulmonary disease.
Spores as Infectious Propagules ofCryptococcus neoformans
Authors: Velagapudi Rajesh , Hsueh Yen-Ping , Geunes-Boyer Scarlett , Wright Jo Rae , Heitman Joseph 
Published: July 2009

ABSTRACTCryptococcus neoformansandCryptococcus gattiiare closely related pathogenic fungi that cause pneumonia and meningitis in both immunocompromised and immunocompetent hosts and are a significant global infectious disease risk. Both species are found in the environment and are acquired via inhalation, leading to an initial pulmonary infection. The infectious propagule is unknown but is hypothesized to be small desiccated yeast cells or spores produced by sexual reproduction (opposite- or same-sex mating). Here we characterize the morphology, germination properties, and virulence of spores. A comparative morphological analysis of hyphae and spores produced by opposite-sex mating, same-sex mating, and self-fertile diploid strains was conducted by scanning electron microscopy, yielding insight into hyphal/basidial morphology and spore size, structure, and surface properties. Spores isolated by microdissection were found to readily germinate even on water agarose medium. Thus, nutritional signals do not appear to be required to stimulate spore germination, and as-yet-unknown environmental factors may normally constrain germination in nature. As few as 500 CFU of a spore-enriched infectious inoculum (∼95% spores) of serotype AC. neoformansvar.grubiiwere fully virulent (100% lethal infection) in both a murine inhalation virulence model and the invertebrate model hostGalleria mellonella. In contrast to a previous report onC. neoformansvar.neoformans, spores ofC. neoformansvar.grubiiwere not more infectious than yeast cells. Molecular analysis of isolates recovered from tissues of infected mice (lung, spleen, and brain) provides evidence for infection and dissemination by recombinant spore products. These studies provide a detailed morphological and physiological analysis of the spore and document that spores can serve as infectious propagules.
A model of message flow control
Authors: Kille S. E. , Brink D. H. 
Published: July 2009

Substantial experience has now been gained in the use of store and forward message systems. At present, most significant systems currently fall into one of the following categories:
- Closed corporate systems, such as the DEC Engineering network.
- Academic / Research networks, such as the DARPA Internet, and the UK Joint Academic Network (JANET).
- Vendor provided services, without interaction with other vendor services (isolated Management Domains in X.400 terminology).
- Single system communities, such as the UUCP community.
Sexual size dimorphism, diet, and reproductive biology of the Afro-Asian Sand Snake, Psammophis schokari (Psammophiidae)
Authors: Cottone Amanda , Bauer Aaron 
Published: July 2009

AbstractWe measured and dissected 226 museum specimens of Psammophis schokari (Schokari Sand Snake), a widespread, common “whipsnake” occurring in North Africa and southwest Asia. Three aspects of its ecology were investigated: sexual size dimorphism (SSD), diet, and reproductive biology. There was no significant SSD in mean body size or shape for the traits measured. The species is an opportunistic feeder, but preys predominately on lizards. Males and females exhibit their highest levels of sexual activity in synchrony and exhibit prenuptial spermiogenesis and a Type 1 vitellogenic cycle, respectively. Mating occurs at the end of the rainy season and clutch sizes are small. These findings from a Northern Hemisphere temperate sand snake are consistent with previous results for both tropical and south temperate Psammophis. These traits thus appear to be highly conserved within the genus and also exhibit convergence with respect to unrelated colubroid “whipsnakes”.
Signed weighted gene co-expression network analysis of transcriptional regulation in murine embryonic stem cells
Authors: Mason Mike J , Fan Guoping , Plath Kathrin , Zhou Qing , Horvath Steve 
Published: July 2009

Abstract

Background
Recent work has revealed that a core group of transcription factors (TFs) regulates the key characteristics of embryonic stem (ES) cells: pluripotency and self-renewal. Current efforts focus on identifying genes that play important roles in maintaining pluripotency and self-renewal in ES cells and aim to understand the interactions among these genes. To that end, we investigated the use of unsigned and signed network analysis to identify pluripotency and differentiation related genes.

Results
We show that signed networks provide a better systems level understanding of the regulatory mechanisms of ES cells than unsigned networks, using two independent murine ES cell expression data sets. Specifically, using signed weighted gene co-expression network analysis (WGCNA), we found a pluripotency module and a differentiation module, which are not identified in unsigned networks. We confirmed the importance of these modules by incorporating genome-wide TF binding data for key ES cell regulators. Interestingly, we find that the pluripotency module is enriched with genes related to DNA damage repair and mitochondrial function in addition to transcriptional regulation. Using a connectivity measure of module membership, we not only identify known regulators of ES cells but also show that Mrpl15, Msh6, Nrf1, Nup133, Ppif, Rbpj, Sh3gl2, and Zfp39, among other genes, have important roles in maintaining ES cell pluripotency and self-renewal. We also report highly significant relationships between module membership and epigenetic modifications (histone modifications and promoter CpG methylation status), which are known to play a role in controlling gene expression during ES cell self-renewal and differentiation.

Conclusion
Our systems biologic re-analysis of gene expression, transcription factor binding, epigenetic and gene ontology data provides a novel integrative view of ES cell biology.
Selection of reliable reference genes for gene expression studies in peach using real-time PCR
Authors: Tong Zhaoguo , Gao Zhihong , Wang Fei , Zhou Jun , Zhang Zhen 
Published: July 2009

Abstract

Background
RT-qPCR is a preferred method for rapid and reliable quantification of gene expression studies. Appropriate application of RT-qPCR in such studies requires the use of reference gene(s) as an internal control to normalize mRNA levels between different samples for an exact comparison of gene expression level. However, recent studies have shown that no single reference gene is universal for all experiments. Thus, the identification of high quality reference gene(s) is of paramount importance for the interpretation of data generated by RT-qPCR. Only a few studies on reference genes have been done in plants and none in peach (Prunus persica L. Batsch). Therefore, the present study was conducted to identify suitable reference gene(s) for normalization of gene expression in peach.

Results
In this work, eleven reference genes were investigated in different peach samples using RT-qPCR with SYBR green. These genes are: actin 2/7 (ACT), cyclophilin (CYP2), RNA polymerase II (RP II), phospholipase A2 (PLA2), ribosomal protein L13 (RPL13), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), 18S ribosomal RNA (18S rRNA), tubblin beta (TUB), tubblin alpha (TUA), translation elongation factor 2 (TEF2) and ubiquitin 10 (UBQ10). All eleven reference genes displayed a wide range of Cq values in all samples, indicating that they expressed variably. The stability of these genes except for RPL13 was determined by three different descriptive statistics, geNorm, NormFinder and BestKeeper, which produced highly comparable results.

Conclusion
Our study demonstrates that expression stability varied greatly between genes studied in peach. Based on the results from geNorm, NormFinder and BestKeeper analyses, for all the sample pools analyzed, TEF2, UBQ10 and RP II were found to be the most suitable reference genes with a very high statistical reliability, and TEF2 and RP II for the other sample series, while 18S rRNA, RPL13 and PLA2 were unsuitable as internal controls. GAPDH and ACT also performed poorly and were less stable in our analysis. To achieve accurate comparison of levels of gene expression, two or more reference genes must be used for data normalization. The combinations of TEF2/UBQ10/RP II and TEF2/RP II were suggested for use in all samples and subsets, respectively.
Identification of an extensive gene cluster among a family of PPOs in Trifolium pratense L. (red clover) using a large insert BAC library
Authors: Winters Ana , Heywood Sue , Farrar Kerrie , Donnison Iain , Thomas Ann , Webb K Judith 
Published: July 2009

Abstract

Background
Polyphenol oxidase (PPO) activity in plants is a trait with potential economic, agricultural and environmental impact. In relation to the food industry, PPO-induced browning causes unacceptable discolouration in fruit and vegetables: from an agriculture perspective, PPO can protect plants against pathogens and environmental stress, improve ruminant growth by increasing nitrogen absorption and decreasing nitrogen loss to the environment through the animal's urine. The high PPO legume, red clover, has a significant economic and environmental role in sustaining low-input organic and conventional farms. Molecular markers for a range of important agricultural traits are being developed for red clover and improved knowledge of PPO genes and their structure will facilitate molecular breeding.

Results
A bacterial artificial chromosome (BAC) library comprising 26,016 BAC clones with an average 135 Kb insert size, was constructed from Trifolium pratense L. (red clover), a diploid legume with a haploid genome size of 440–637 Mb. Library coverage of 6–8 genome equivalents ensured good representation of genes: the library was screened for polyphenol oxidase (PPO) genes.
Two single copy PPO genes, PPO4 and PPO5, were identified to add to a family of three, previously reported, paralogous genes (PPO1–PPO3). Multiple PPO1 copies were identified and characterised revealing a subfamily comprising three variants PPO1/2, PPO1/4 and PPO1/5. Six PPO genes clustered within the genome: four separate BAC clones could be assembled onto a predicted 190–510 Kb single BAC contig.

Conclusion
A PPO gene family in red clover resides as a cluster of at least 6 genes. Three of these genes have high homology, suggesting a more recent evolutionary event. This PPO cluster covers a longer region of the genome than clusters detected in rice or previously reported in tomato. Full-length coding sequences from PPO4, PPO5, PPO1/5 and PPO1/4 will facilitate functional studies and provide genetic markers for plant breeding.
Association study between vitamin D receptor gene polymorphisms and asthma in the chinese han population: a case-control study
Authors: Saadi Ahlem , Gao Guimin , Li Huaichen , Wei Chunhua , Gong Yaoqin , Liu Qiji 
Published: July 2009

Abstract

Background
Modulation of the immune system is one of the principal roles of Vitamin D, for which the effects are exerted via the vitamin D receptor (VDR). Importantly, variants in the VDR gene have been susceptible in the past to raise the risk of asthma in several populations. These effects of VDR allelic markers remain speculative in the Chinese Han population.

Results
A case-control study of 1090 individuals including 567 asthmatic patients was realized on five SNPs within the VDR gene. Only rs7975232 (ApaI) marker showed a significant association with asthma (P = 0.009). Haplotype analysis of the five VDR polymorphisms showed a significant association with asthma (global-p value = 0.012).

Conclusion
Although the susceptibility of VDR gene variants with asthma could not be confirmed for all SNPs tested in this study, the significant association obtained for rs7975232 provides evidence for a previously unknown report about the Chinese Han population and may raise the susceptibility of VDR to be a candidate gene for asthma.