Electronic spectroscopy of 9,10-dichloroanthracene inside helium droplets

The spectroscopy of molecules doped into superfluid helium droplets provides information on both, the dopant molecule and the helium environment. Electronic spectra of 9,10-dichloroanthracene in helium droplets are presented and compared with corresponding gas phase spectra to unravel the influence of the helium environment. The combined investigation of fluorescence excitation and dispersed emission provides information on dynamic processes in addition to energetic conditions. For vibronic states, the helium induced decay channels dominate over all intramolecular channels that contribute to the gas phase behavior. In addition to the triplet splitting caused by the Cl isotopes, a fine structure resolved for all transitions in the fluorescence excitation spectrum was found, which is the signature of microsolvation of this compound in helium droplets. This fine structure is identified as a single pure molecular transition accompanied by a sharply structured phonon wing. The corresponding fine structure measured for bare anthracene shows remarkable differences

Improved setup for producing slow beams of cold molecules using a rotating nozzle

Intense beams of cold and slow molecules are produced by supersonic expansion out of a rapidly rotating nozzle, as first demonstrated by Gupta and Herschbach. An improved setup is presented that allows to accelerate or decelerate cold atomic and molecular beams by up to 500 m/s. Technical improvements are discussed and beam parameters are characterized by detailed analysis of time of flight density distributions. The possibility of combining this beam source with electrostatic fields for guiding polar molecules is demonstrated

Release of Viral Glycoproteins during Ebola Virus Infection

AbstractMaturation and release of the Ebola virus glycoprotein GP were studied in cells infected with either Ebola or recombinant vaccinia viruses. Significant amounts of GP were found in the culture medium in nonvirion forms. The major form represented the large subunit GP1that was shed after release of its disulfide linkage to the smaller transmembrane subunit GP2. The minor form were intact GP1,2complexes incorporated into virosomes. Vector-expressed GP formed spikes morphologically indistinguishable from spikes on virus particles, indicating that spike assembly is independent of other viral proteins. Analysis of a truncation mutant revealed an early and almost complete release of GP1,2molecules, showing that membrane anchoring is mediated by the carboxy-terminal hydrophobic domain of GP2. We have also compared wild-type virus which requires transcriptional editing for synthesis of full-length GP with a variant that does not depend on editing. Both viruses released comparable amounts of GP1, but the variant expressed only minute amounts of the small, soluble GP which is the expression product of nonedited mRNA species of the GP gene. The abundant shedding of soluble GP1may play an important role in the immunopathology of Ebola hemorrhagic fever in experimentally and naturally infected hosts

The Use of a Mobile Laboratory Unit in Support of Patient Management and Epidemiological Surveillance during the 2005 Marburg Outbreak in Angola

A mobile laboratory unit (MLU) was deployed to Uige, Angola as part of the World Health Organization response to an outbreak of viral hemorrhagic fever caused by Marburg virus (MARV). Utilizing mainly quantitative real-time PCR assays, this laboratory provided specific MARV diagnostics in the field. The MLU operated for 88 consecutive days allowing MARV-specific diagnostic response in <4 hours from sample receiving. Most cases were found among females in the child-bearing age and in children less than five years of age including a high number of paediatric cases implicating breastfeeding as potential transmission route. Oral swabs were identified as a useful alternative specimen source to the standard whole blood/serum specimens for patients refusing blood draw. There was a high concordance in test results between the MLU and the reference laboratory in Luanda operated by the US Centers for Disease Control and Prevention. The MLU was an important outbreak response asset providing valuable support in patient management and epidemiological surveillance. Field laboratory capacity should be expanded and made an essential part of any future outbreak investigation

New filovirus disease classification and nomenclature

Filoviruses, the members of the family Filoviridae, are currently classified into one proposed and five established genera (Supplementary Table 1). Of the twelve described filoviruses, six have been identified as aetiological agents of naturally occurring human disease outbreaks

New filovirus disease classification and nomenclature.

The recent large outbreak of Ebola virus disease (EVD) in Western Africa resulted in greatly increased accumulation of human genotypic, phenotypic and clinical data, and improved our understanding of the spectrum of clinical manifestations. As a result, the WHO disease classification of EVD underwent major revision

Electric Linear Dichroism with a Simple Interpretation in Terms of Molecular Pendular States

An anisotropic orientation of the figure axis of elec. dipolar ICl is forced by a strong homogeneous elec. field. The mol. is transferred into a pendular state and shows optical anisotropy due to the body fixed mol. transition dipole moment. This holds in exactly the same way for magnetically dipolar mols. in a homogeneous magnetic field. A simple geometric model is applied which simulates all spectral features quant. without any fitting procedure for both the elec. and the magnetic case. The sparse structure of polarization spectra of such a sample allows for easy reading of spectroscopic consts. and study of electronic states of even large mols

Quantum solvation of phthalocyanine in superfluid helium droplets

The authors have measured quantum states of the solvent-solute system of phthalocyanine in superfluid He droplets in a high resoln. pump-probe expt. This provides evidence for the attribution of a splitting effect in the emission spectra of phthalocyanine in He droplets to the relaxation of the 1st He layer upon electronic excitation, measured recently by the authors. The authors' exptl. results are a strong indication for the 1st He layer playing a key role for the solvation of mols. in He droplets and, thus, for their spectroscopic features