Hydrothermal Synthesis, Microstructure and Photoluminescence of Eu3+-Doped Mixed Rare Earth Nano-Orthophosphates

Eu3+-doped mixed rare earth orthophosphates (rare earth = La, Y, Gd) have been prepared by hydrothermal technology, whose crystal phase and microstructure both vary with the molar ratio of the mixed rare earth ions. For LaxY1–xPO4: Eu3+, the ion radius distinction between the La3+ and Y3+ is so large that only La0.9Y0.1PO4: Eu3+ shows the pure monoclinic phase. For LaxGd1–xPO4: Eu3+ system, with the increase in the La content, the crystal phase structure of the product changes from the hexagonal phase to the monoclinic phase and the microstructure of them changes from the nanorods to nanowires. Similarly, YxGd1–xPO4: Eu3+, Y0.1Gd0.9PO4: Eu3+ and Y0.5Gd0.5PO4: Eu3+ samples present the pure hexagonal phase and nanorods microstructure, while Y0.9Gd0.1PO4: Eu3+ exhibits the tetragonal phase and nanocubic micromorphology. The photoluminescence behaviors of Eu3+ in these hosts are strongly related to the nature of the host (composition, crystal phase and microstructure)

VILIP-1 Downregulation in Non-Small Cell Lung Carcinomas: Mechanisms and Prediction of Survival

VILIP-1, a member of the neuronal Ca++ sensor protein family, acts as a tumor suppressor gene in an experimental animal model by inhibiting cell proliferation, adhesion and invasiveness of squamous cell carcinoma cells. Western Blot analysis of human tumor cells showed that VILIP-1 expression was undetectable in several types of human tumor cells, including 11 out of 12 non-small cell lung carcinoma (NSCLC) cell lines. The down-regulation of VILIP-1 was due to loss of VILIP-1 mRNA transcripts. Rearrangements, large gene deletions or mutations were not found. Hypermethylation of the VILIP-1 promoter played an important role in gene silencing. In most VILIP-1-silent cells the VILIP-1 promoter was methylated. In vitro methylation of the VILIP-1 promoter reduced its activity in a promoter-reporter assay. Transcriptional activity of endogenous VILIP-1 promoter was recovered by treatment with 5′-aza-2′-deoxycytidine (5′-Aza-dC). Trichostatin A (TSA), a histone deacetylase inhibitor, potently induced VILIP-1 expression, indicating that histone deacetylation is an additional mechanism of VILIP-1 silencing. TSA increased histone H3 and H4 acetylation in the region of the VILIP-1 promoter. Furthermore, statistical analysis of expression and promoter methylation (n = 150 primary NSCLC samples) showed a significant relationship between promoter methylation and protein expression downregulation as well as between survival and decreased or absent VILIP-1 expression in lung cancer tissues (p<0.0001). VILIP-1 expression is silenced by promoter hypermethylation and histone deacetylation in aggressive NSCLC cell lines and primary tumors and its clinical evaluation could have a role as a predictor of short-term survival in lung cancer patients

Insights from Modeling the 3D Structure of New Delhi Metallo-β-Lactamse and Its Binding Interactions with Antibiotic Drugs

New Delhi metallo-beta-lactamase (NDM-1) is an enzyme that makes bacteria resistant to a broad range of beta-lactam antibiotic drugs. This is because it can inactivate most beta-lactam antibiotic drugs by hydrolyzing them. For in-depth understanding of the hydrolysis mechanism, the three-dimensional structure of NDM-1 was developed. With such a structural frame, two enzyme-ligand complexes were derived by respectively docking Imipenem and Meropenem (two typical beta-lactam antibiotic drugs) to the NDM-1 receptor. It was revealed from the NDM-1/Imipenem complex that the antibiotic drug was hydrolyzed while sitting in a binding pocket of NDM-1 formed by nine residues. And for the case of NDM-1/Meropenem complex, the antibiotic drug was hydrolyzed in a binding pocket formed by twelve residues. All these constituent residues of the two binding pockets were explicitly defined and graphically labeled. It is anticipated that the findings reported here may provide useful insights for developing new antibiotic drugs to overcome the resistance problem

Development of Useful Recombinant Promoter and Its Expression Analysis in Different Plant Cells Using Confocal Laser Scanning Microscopy

BACKGROUND: Designing functionally efficient recombinant promoters having reduced sequence homology and enhanced promoter activity will be an important step toward successful stacking or pyramiding of genes in a plant cell for developing transgenic plants expressing desired traits(s). Also basic knowledge regarding plant cell specific expression of a transgene under control of a promoter is crucial to assess the promoter's efficacy. METHODOLOGY/PRINCIPAL FINDINGS: We have constructed a set of 10 recombinant promoters incorporating different up-stream activation sequences (UAS) of Mirabilis mosaic virus sub-genomic transcript (MS8, -306 to +27) and TATA containing core domains of Figwort mosaic virus sub-genomic transcript promoter (FS3, -271 to +31). Efficacies of recombinant promoters coupled to GUS and GFP reporter genes were tested in tobacco protoplasts. Among these, a 369-bp long hybrid sub-genomic transcript promoter (MSgt-FSgt) showed the highest activity in both transient and transgenic systems. In a transient system, MSgt-FSgt was 10.31, 2.86 and 2.18 times more active compared to the CaMV35S, MS8 and FS3 promoters, respectively. In transgenic tobacco (Nicotiana tabaccum, var. Samsun NN) and Arabidopsis plants, the MSgt-FSgt hybrid promoter showed 14.22 and 7.16 times stronger activity compared to CaMV35S promoter respectively. The correlation between GUS activity and uidA-mRNA levels in transgenic tobacco plants were identified by qRT-PCR. Both CaMV35S and MSgt-FSgt promoters caused gene silencing but the degree of silencing are less in the case of the MSgt-FSgt promoter compared to CaMV35S. Quantification of GUS activity in individual plant cells driven by the MSgt-FSgt and the CaMV35S promoter were estimated using confocal laser scanning microscopy and compared. CONCLUSION AND SIGNIFICANCE: We propose strong recombinant promoter MSgt-FSgt, developed in this study, could be very useful for high-level constitutive expression of transgenes in a wide variety of plant cells

Localization and broadband follow-up of the gravitational-wave transient GW150914

A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams

Prospects for Observing and Localizing Gravitational-Wave Transients with Advanced LIGO and Advanced Virgo.

We present a possible observing scenario for the Advanced LIGO and Advanced Virgo gravitational-wave detectors over the next decade, with the intention of providing information to the astronomy community to facilitate planning for multi-messenger astronomy with gravitational waves. We determine the expected sensitivity of the network to transient gravitational-wave signals, and study the capability of the network to determine the sky location of the source. We report our findings for gravitational-wave transients, with particular focus on gravitational-wave signals from the inspiral of binary neutron-star systems, which are considered the most promising for multi-messenger astronomy. The ability to localize the sources of the detected signals depends on the geographical distribution of the detectors and their relative sensitivity, and 90% credible regions can be as large as thousands of square degrees when only two sensitive detectors are operational. Determining the sky position of a significant fraction of detected signals to areas of 5 deg2 to 20 deg2 will require at least three detectors of sensitivity within a factor of ∼ 2 of each other and with a broad frequency bandwidth. Should the third LIGO detector be relocated to India as expected, a significant fraction of gravitational-wave signals will be localized to a few square degrees by gravitational-wave observations alone

Binary Black Hole Mergers in the first Advanced LIGO Observing Run

The first observational run of the Advanced LIGO detectors, from September 12, 2015 to January 19, 2016, saw the first detections of gravitational waves from binary black hole mergers. In this paper we present full results from a search for binary black hole merger signals with total masses up to $100 M_\odot$ and detailed implications from our observations of these systems. Our search, based on general-relativistic models of gravitational wave signals from binary black hole systems, unambiguously identified two signals, GW150914 and GW151226, with a significance of greater than $5\sigma$ over the observing period. It also identified a third possible signal, LVT151012, with substantially lower significance, which has a 87% probability of being of astrophysical origin. We provide detailed estimates of the parameters of the observed systems. Both GW150914 and GW151226 provide an unprecedented opportunity to study the two-body motion of a compact-object binary in the large velocity, highly nonlinear regime. We do not observe any deviations from general relativity, and place improved empirical bounds on several high-order post-Newtonian coefficients. From our observations we infer stellar-mass binary black hole merger rates lying in the range $9-240 \mathrm{Gpc}^{-3} \mathrm{yr}^{-1}$. These observations are beginning to inform astrophysical predictions of binary black hole formation rates, and indicate that future observing runs of the Advanced detector network will yield many more gravitational wave detections

Observation of Gravitational Waves from a Binary Black Hole Merger

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0 × 10−21. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410þ160 −180 Mpc corresponding to a redshift z ¼ 0.09þ0.03 −0.04 . In the source frame, the initial black hole masses are 36þ5 −4M⊙ and 29þ4 −4M⊙, and the final black hole mass is 62þ4 −4M⊙, with 3.0þ0.5 −0.5M⊙c2 radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger