Insights from twenty years of comparative research in Pacific Large Ocean States

Under global environmental change, understanding the interactions between people and nature has become critical for human survival. Comparative research can identify trends within social-ecological systems providing key insights for both environmental and developmental research. Island systems, with clear land boundaries, have been proposed as ideal case studies for comparative research, but it is unclear to what extent their potential has been fulfilled. To summarize existing research and identify potential gaps and new directions, we reviewed comparative environmental and developmental research on Pacific Large Ocean States. A diversity of case study locations and research themes were addressed within the sample of reviewed studies. Within the reviewed literature climate change, energy infrastructure, trade and fisheries were key themes of environmental and developmental research compared between island systems. Research was biased towards wealthier Pacific Large Ocean States and those with a relatively higher degree of socio-economic development. Our review highlights the potential value of a stronger a priori inclusion of spatial scale and conceptual frameworks, such as spatial resilience, to facilitate generalization from case studies

Binding of lac repressor-GFP fusion protein to lac operator sites inserted in the tobacco chloroplast genome examined by chromatin immunoprecipitation

Chromatin immunoprecipitation (ChIP) has been used to detect binding of DNA-binding proteins to sites in nuclear and mitochondrial genomes. Here, we describe a method for detecting protein-binding sites on chloroplast DNA, using modifications to the nuclear ChIP procedures. The method was developed using the lac operator (lacO)/lac repressor (LacI) system from Escherichia coli. The lacO sequences were integrated into a single site between the rbcL and accD genes in tobacco plastid DNA and homoplasmic transplastomic plants were crossed with transgenic tobacco plants expressing a nuclear-encoded plastid-targeted GFP-LacI fusion protein. In the progeny, the GFP-LacI fusion protein could be visualized in living tissues using confocal microscopy, and was found to co-localize with plastid nucleoids. Isolated chloroplasts from the lacO/GFP-LacI plants were lysed, treated with micrococcal nuclease to digest the DNA to fragments of ∼600 bp and incubated with antibodies to GFP and protein A-Sepharose. PCR analysis on DNA extracted from the immunoprecipitate demonstrated IPTG (isopropylthiogalactoside)-sensitive binding of GFP-LacI to lacO. Binding of GFP-LacI to endogenous sites in plastid DNA showing sequence similarity to lacO was also detected, but required reversible cross-linking with formaldehyde. This may provide a general method for the detection of binding sites on plastid DNA for specific proteins

Direct CP-asymmetry in Inclusive Rare B-decays in 2HDM

The direct CP-asymmetry in the inclusive $B \to X_d \gamma$ and $B \to X_d e^+ e^ -$ decays is investigated in the two-Higgs doublet extension of the Standard Model (2HDM). The investigation is performed in the lowest non-vanishing order of the perturbation theory using the existing restrictions on the 2HDM parameters space. It is shown that the direct CP-asymmetry in the $B \to X_d \gamma$ decay can deviate significantly from the Standard Model predictions. In the presence of only one source of CP-violation (the CKM matrix weak phase) $a_{CP}(B \to X_d \gamma)$ can have the sign opposite to that in the SM. The new source of CP-violation can make $|a_{CP}(B \to X_d \gamma)|$ arbitrary small (unlike the SM case) and hence unmeasurable. Quantitatively, the obtained results suffer from the uncertainty of the choice of renormalization scale. As for the $B \to X_d e^+ e^ -$ rate asymmetry, its renormalization scale dependence in the lowest non-vanishing order does not allow to conclude if this quantity is efficient for testing New Physics beyond the Standard Model.Comment: 16 pages including 2 figure

Azimuthal Angle Distribution in B→K∗(→Kπ)ℓ+ℓ−B \to K^* (\to K \pi) \ell^+ \ell^- at low invariant mℓ+ℓ−m_{\ell^+ \ell^-} Region

We present the angular distribution of the rare B decay, $B \to K^* (\to K \pi) \ell^+ \ell^-$. By studying the azimuthal angle distribution in the low invariant mass region of dileptons, we can probe new physics effects efficiently. In particular, this distribution is found to be quite sensitive to the ratio of the contributions from two independent magnetic moment operators, which also contribute to $B \to K^* \gamma$. Therefore, our method can be very useful when new physics is introduced without changing the total decay rate of the $b \to s \gamma$. The angular distributions are compared with the predictions of the standard model, and are shown for the cases when the afore-mentioned ratio is different from the standard model prediction.Comment: 20pages, RevTeX, 6 figures, minor changes in discussio

The sympathetic tone mediates leptin's inhibition of insulin secretion by modulating osteocalcin bioactivity

The osteoblast-secreted molecule osteocalcin favors insulin secretion, but how this function is regulated in vivo by extracellular signals is for now unknown. In this study, we show that leptin, which instead inhibits insulin secretion, partly uses the sympathetic nervous system to fulfill this function. Remarkably, for our purpose, an osteoblast-specific ablation of sympathetic signaling results in a leptin-dependent hyperinsulinemia. In osteoblasts, sympathetic tone stimulates expression of Esp, a gene inhibiting the activity of osteocalcin, which is an insulin secretagogue. Accordingly, Esp inactivation doubles hyperinsulinemia and delays glucose intolerance in ob/ob mice, whereas Osteocalcin inactivation halves their hyperinsulinemia. By showing that leptin inhibits insulin secretion by decreasing osteocalcin bioactivity, this study illustrates the importance of the relationship existing between fat and skeleton for the regulation of glucose homeostasis

The Acinetobacter baumannii two-component system aders regulates genes required for multidrug efflux, biofilm formation, and virulence in a strain-specific manner

The opportunistic pathogen Acinetobacter baumannii is able to persist in the environment and is often multidrug resistant (MDR), causing difficulties in the treatment of infections. Here, we show that the two-component system AdeRS, which regulates the production of the AdeABC multidrug resistance efflux pump, is required for the formation of a protective biofilm in an ex vivo porcine mucosal model, which mimics a natural infection of the human epithelium. Interestingly, deletion of adeB impacted only on the ability of strain AYE to form a biofilm on plastic and only on the virulence of strain Singapore 1 for Galleria mellonella. RNA-Seq revealed that loss of AdeRS or AdeB significantly altered the transcriptional landscape, resulting in the changed expression of many genes, notably those associated with antimicrobial resistance and virulence interactions. For example, A. baumannii lacking AdeRS displayed decreased expression of adeABC, pil genes, com genes, and a pgaC-like gene, whereas loss of AdeB resulted in increased expression of pil and com genes and decreased expression of ferric acinetobactin transport system genes. These data define the scope of AdeRS-mediated regulation, show that changes in the production of AdeABC mediate important phenotypes controlled by AdeRS, and suggest that AdeABC is a viable target for antimicrobial drug and antibiofilm discovery. IMPORTANCE Acinetobacter baumannii is a nosocomial pathogen and is an increasing problem in hospitals worldwide. This organism is often multidrug resistant, can persist in the environment, and forms a biofilm on environmental surfaces and wounds. Overproduction of efflux pumps can allow specific toxic compounds to be pumped out of the cell and can lead to multidrug resistance. This study demonstrates the role of the A. baumannii efflux pump AdeB, and its regulator AdeRS, in multidrug resistance, epithelial cell killing, and biofilm formation. Deletion of the genes encoding these systems led to increased susceptibility to antibiotics, decreased biofilm formation on biotic and abiotic surfaces, and decreased virulence. Our data suggest that inhibition of AdeB could prevent biofilm formation or colonization in patients by A. baumannii and provides a good target for drug discovery

Probing SUSY-induced CP violations at B factories

In the minimal supersymmetric standard model (MSSM), the \mu-parameter and the trilinear coupling A_t may be generically complex and can affect various observables at B factories. Imposing the edm constraints, we find that there is no new large phase shift in the B^0 - \bar{B^0} mixing, CP violating dilepton asymmetry is smaller than 0.1 %, and the direct CP violation in B\to X_s \gamma can be as large as \sim \pm 16 %.Comment: 4 pages, 2 figures. Version to appear in Phys. Rev. Let

An Osteoblast-dependent Mechanism Contributes to the Leptin Regulation of Insulin Secretion

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72661/1/j.1749-6632.2009.05061.x.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/72661/2/NYAS_5061_sm_SuppMat.pd

Hadronic B decays: Supersymmetric enhancement and a simple spectator model

Two aspects of hadronic B decays are investigated. Firstly, the supersymmetric enhancement of hadronic b decays by gluino penguin processes is studied through their effect on the Wilson coefficients of the effective Hamiltonian. Secondly, hadronization of the final state quarks is studied through a simple phase space spectator model.Comment: 24 pages, REVTEX, minor additional text and some references adde

Direct CP violation in radiative b decays in and beyond the Standard Model

We consider the partial rate asymmetry in the inclusive decay modes b to s gamma and b to d gamma, concentrating on non-standard models with new charged Higgs interactions. We find that the charged Higgs contribution to the asymmetry for b to s gamma is small in such models due to a universal cancellation mechanism. The asymmetry is therefore difficult to distinguish experimentally from the Standard Model (SM) value, which is also small. The cancellation mechanism is found to be rendered inoperative in supersymmetry due to the presence of chargino loops. Unlike b to s gamma, the rate asymmetry for b to d gamma in Higgs models can be quite different from its SM value, generally ranging from -20% to +20%. Specific model calculations are performed for the Three-Higgs Doublet Model and the ``Top'' Two-Higgs Doublet Model to serve as illustrations. We also offer some suggestions that may be helpful to experimentalists in the detection of the inclusive mode b to d gamma.Comment: RevTex, 24 pages, 6 figures, minor changes, version to appear in PR