Interference bands in decays of doubly-charged Higgs bosons to dileptons in the minimal type-II seesaw model at the TeV scale

The dileptonic decays of doubly-charged Higgs bosons H^{\pm\pm} are investigated in the minimal type-II seesaw model with one Higgs triplet \Delta and one heavy Majorana neutrino N_1 at the TeV scale. We show that the branching ratios {\cal B}(H^{\pm\pm} \to l^\pm_\alpha l^\pm_\beta) depend not only on the mass and mixing parameters of three light neutrinos \nu_i (for i=1,2,3), but also on those of N_1. Assuming the mass of N_1 to lie in the range 200 GeV--1 TeV, we figure out the generous interference bands for the contributions of \nu_i and N_1 to {\cal B}(H^{\pm\pm} \to l^\pm_\alpha l^\pm_\beta): \sqrt{|\sin\theta_{i4} \sin\theta_{j4}|} \sim 10^{-8}--10^{-5}, where \theta_{i4} and \theta_{j4} measure the strength of charged-current interactions of N_1. We illustrate some salient features of the interference bands by considering three typical mass patterns of \nu_i, and stress that it is very difficult to distinguish the type-II seesaw model from the triplet seesaw model in such a parameter region at the Large Hadron Collider.Comment: RevTex 14 pages, 3 figures, more discussions added, accepted for publication in Phys. Lett.

Correlation between the Charged Current Interactions of Light and Heavy Majorana Neutrinos

The evidence for neutrino oscillations implies that three neutrino flavors (\nu_e, \nu_\mu, \nu_\tau) must have different mass states (\nu_1, \nu_2, \nu_3). The most popular idea of generating tiny masses of \nu_i is to introduce three heavy Majorana neutrinos N_i (for i = 1, 2, 3) into the standard model and implement the seesaw mechanism. In this approach the neutrino mixing matrix V appearing in the charged current interactions of \nu_i is not unitary, and the strength of unitarity violation of V is associated with the matrix R which describes the strength of charged current interactions of N_i. We present an explicit parametrization of the correlation between V and R in terms of nine rotation angles and nine phase angles, which can be measured or constrained in the precision neutrino oscillation experiments and by exploring possible signatures of N_i at the LHC and ILC. Two special but viable scenarios, the Type-I seesaw model with two heavy Majorana neutrinos and the Type-II seesaw model with one heavy Majorana neutrino and one Higgs triplet, are taken into account to illustrate the simplified V-R correlation. The implications of R \neq 0 on the low-energy neutrino phenomenology are also discussed. In particular, we demonstrate that the non-unitarity of V is possible to give rise to an appreciable CP-violating asymmetry between \nu_\mu -> \nu_\tau and \bar{\nu}_\mu -> \bar{\nu}_\tau oscillations with short or medium baselines.Comment: RevTex 13 pages (1 figure). Some minor corrections and changes. Accepted for publication in Phys. Lett.

Epidemiologic Characterization of Human Papillomavirus Infection in Rural Chaozhou, Eastern Guangdong Province of China

BACKGROUND: Human papilloma virus (HPV) infection was the main cause of cervical cancer. There were only a few reports and detailed data about epidemiological research of HPV infection in rural population of China. MATERIALS AND METHODS: The cervical cells of rural Chaozhou women were collected, and multiplex real time PCR was firstly performed to detect high-risk HPV (HR-HPV) infection, which could detect 13 types of HR-HPV (types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68). Then, HPV-positive samples were typed by HPV GenoArray test. RESULTS: HR-HPV DNA was detected by multiplex real time-PCR in 3830 of 48559 cases (7.89%). There was a peak incidence in age of 55-60 years group, and a lower incidence in who lived in plain group compared with suburban, mountain and seashore group. 3380 cases of HPV positive sample were genotyped, 11.01% (372/3380) cases could not be classified, among the typed 3008 cases, 101 cases were identified without HR-HPV type infection, 2907 cases were infected with one HR-HPV type at least, the 6 most common HR-HPV types in descending order of infection, were type 52 (33.4%, 16 (20.95%), 58 (15.93%), 33 (9.94%), 68 (9.22%) and 18 (8.36%). The combined prevalence of HPV types 16 and 18 accounted for 28.52% of total infection. However, type 52 plus 58 presented 48.23% of total infection. 2209/2907 cases were infected with a single HPV type and 698/2907 cases were infected with multiple types, and multiple infection constituent ratio increased with age, with a peak incidence in age 55-60 years group. CONCLUSIONS: Our findings showed low prevalence of HPV vaccine types (16 and 18) and relatively high prevalence of HPV-52 and -58, support the hypothesis that the second-generation HPV vaccines including HPV-52 and -58 may offer higher protection for women in rural Guangdong Province

Successful and efficient DNA extraction from processed pangolin scales

A successful method for total DNA extraction from crude and processed pangolin scales was established. After pretreatment in the soaking solution for cleansing, the scales were prepared into fine powders and treated with PBS buffer containing 0.1% collagenase and 0.1% trypsin for 24 h, followed by digestion with proteinase K at 55°C for 120 h. Phenol-chloroform extraction was used to obtain the total DNA. PCR amplification for mitochondrial cytochrome b (cytb) gene was successful using the extracted DNA as the template, and sequencing of the amplified fragments confirmed Manis origin of the scale samples. With an efficiency up to 100%, this method is expected to provide a powerful tool in molecular identification of processed as well as crude pangolin scales

Dopamine Induced Neurodegeneration in a PINK1 Model of Parkinson's Disease

Parkinson's disease is a common neurodegenerative disease characterised by progressive loss of dopaminergic neurons, leading to dopamine depletion in the striatum. Mutations in the PINK1 gene cause an autosomal recessive form of Parkinson's disease. Loss of PINK1 function causes mitochondrial dysfunction, increased reactive oxygen species production and calcium dysregulation, which increases susceptibility to neuronal death in Parkinson's disease. The basis of neuronal vulnerability to dopamine in Parkinson's disease is not well understood

PmoB subunit of particulate methane monooxygenase (pMMO) in Methylococcus capsulatus (Bath): The Cu^I sponge and its function

In this study, we describe efforts to clarify the role of the copper cofactors associated with subunit B (PmoB) of the particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) (M. capsulatus). This subunit exhibits strong affinity toward Cu^I ions. To elucidate the high copper affinity of the subunit, the full-length PmoB, and the N-terminal truncated mutants PmoB_(33–414) and PmoB_(55–414), each fused to the maltose-binding protein (MBP), are cloned and over-expressed into Escherichia coli (E. coli) K12 TB1 cells. The Y374F, Y374S and M300L mutants of these protein constructs are also studied. When this E. coli is grown with the pmoB gene in 1.0 mM Cu^(II), it behaves like M. capsulatus (Bath) cultured under high copper stresswith abundant membrane accumulation and high CuI content. The recombinantPmoB proteins are verified by Western blotting of antibodies directed against the MBP sub-domain in each of the copper-enriched PmoB proteins. Cu K-edge X-rayabsorption near edge spectroscopy (XANES) of the copper ions confirms that all the PmoB recombinants are Cu^I proteins. All the PmoB proteins show evidence of a “dicopper site” according to analysis of the Cu extended X-ray absorption edge fine structure (EXAFS) of the membranes. No specific activities toward methane and propene oxidation are observed with the recombinant membrane-bound PmoB proteins. However, significant production of hydrogen peroxide is observed in the case of the PmoB_(33–414) mutant. Reaction of the dicopper site with dioxygenproduces hydrogen peroxide and leads to oxidation of the CuI ions residing in the C-terminal sub-domain of the PmoB subunit

Differential gene expression and potential regulatory network of fatty acid biosynthesis during fruit and leaf development in yellowhorn (Xanthoceras sorbifolium), an oil-producing tree with significant deployment values

Xanthoceras sorbifolium (yellowhorn) is a woody oil plant with super stress resistance and excellent oil characteristics. The yellowhorn oil can be used as biofuel and edible oil with high nutritional and medicinal value. However, genetic studies on yellowhorn are just in the beginning, and fundamental biological questions regarding its very long-chain fatty acid (VLCFA) biosynthesis pathway remain largely unknown. In this study, we reconstructed the VLCFA biosynthesis pathway and annotated 137 genes encoding relevant enzymes. We identified four oleosin genes that package triacylglycerols (TAGs) and are specifically expressed in fruits, likely playing key roles in yellowhorn oil production. Especially, by examining time-ordered gene co-expression network (TO-GCN) constructed from fruit and leaf developments, we identified key enzymatic genes and potential regulatory transcription factors involved in VLCFA synthesis. In fruits, we further inferred a hierarchical regulatory network with MYB-related (XS03G0296800) and B3 (XS02G0057600) transcription factors as top-tier regulators, providing clues into factors controlling carbon flux into fatty acids. Our results offer new insights into key genes and transcriptional regulators governing fatty acid production in yellowhorn, laying the foundation for efforts to optimize oil content and fatty acid composition. Moreover, the gene expression patterns and putative regulatory relationships identified here will inform metabolic engineering and molecular breeding approaches tailored to meet biofuel and bioproduct demands

PmoB subunit of particulate methane monooxygenase (pMMO) in Methylococcus capsulatus (Bath): The Cu^I sponge and its function

In this study, we describe efforts to clarify the role of the copper cofactors associated with subunit B (PmoB) of the particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) (M. capsulatus). This subunit exhibits strong affinity toward Cu^I ions. To elucidate the high copper affinity of the subunit, the full-length PmoB, and the N-terminal truncated mutants PmoB_(33–414) and PmoB_(55–414), each fused to the maltose-binding protein (MBP), are cloned and over-expressed into Escherichia coli (E. coli) K12 TB1 cells. The Y374F, Y374S and M300L mutants of these protein constructs are also studied. When this E. coli is grown with the pmoB gene in 1.0 mM Cu^(II), it behaves like M. capsulatus (Bath) cultured under high copper stresswith abundant membrane accumulation and high CuI content. The recombinantPmoB proteins are verified by Western blotting of antibodies directed against the MBP sub-domain in each of the copper-enriched PmoB proteins. Cu K-edge X-rayabsorption near edge spectroscopy (XANES) of the copper ions confirms that all the PmoB recombinants are Cu^I proteins. All the PmoB proteins show evidence of a “dicopper site” according to analysis of the Cu extended X-ray absorption edge fine structure (EXAFS) of the membranes. No specific activities toward methane and propene oxidation are observed with the recombinant membrane-bound PmoB proteins. However, significant production of hydrogen peroxide is observed in the case of the PmoB_(33–414) mutant. Reaction of the dicopper site with dioxygenproduces hydrogen peroxide and leads to oxidation of the CuI ions residing in the C-terminal sub-domain of the PmoB subunit