Energy dependence of the transverse momentum distributions of charged particles in pp collisions measured by ALICE

Differential cross sections of charged particles in inelastic pp collisions as a function of p_T have been measured at [Formula: see text] at the LHC. The p_T spectra are compared to NLO-pQCD calculations. Though the differential cross section for an individual [Formula: see text] cannot be described by NLO-pQCD, the relative increase of cross section with [Formula: see text] is in agreement with NLO-pQCD. Based on these measurements and observations, procedures are discussed to construct pp reference spectra at [Formula: see text] up to p_T=50 GeV/c as required for the calculation of the nuclear modification factor in nucleus-nucleus and proton-nucleus collisions.

Directed flow of charged particles at midrapidity relative to the spectator plane in Pb-Pb collisions at √(s(NN))=2.76 TeV

The directed flow of charged particles at midrapidity is measured in Pb-Pb collisions at √(s(NN))=2.76 TeV relative to the collision symmetry plane defined by the spectator nucleons. A negative slope of the rapidity-odd directed flow component with approximately 3 times smaller magnitude than found at the highest RHIC energy is observed. This suggests a smaller longitudinal tilt of the initial system and disfavors the strong fireball rotation predicted for the LHC energies. The rapidity-even directed flow component is measured for the first time with spectators and found to be independent of pseudorapidity with a sign change at transverse momenta p(T) between 1.2 and 1.7  GeV/c. Combined with the observation of a vanishing rapidity-even p(T) shift along the spectator deflection this is strong evidence for dipolelike initial density fluctuations in the overlap zone of the nuclei. Similar trends in the rapidity-even directed flow and the estimate from two-particle correlations at midrapidity, which is larger by about a factor of 40, indicate a weak correlation between fluctuating participant and spectator symmetry planes. These observations open new possibilities for investigation of the initial conditions in heavy-ion collisions with spectator nucleons.

K(S)0 and Λ production in Pb-Pb collisions at √(s(NN))=2.76 TeV

The ALICE measurement of K(S)(0) and Λ production at midrapidity in Pb-Pb collisions at √(s(NN))=2.76 TeV is presented. The transverse momentum (p(T)) spectra are shown for several collision centrality intervals and in the p(T) range from 0.4 GeV/c (0.6 GeV/c for Λ) to 12 GeV/c. The p(T) dependence of the Λ/K(S)(0) ratios exhibits maxima in the vicinity of 3 GeV/c, and the positions of the maxima shift towards higher p(T) with increasing collision centrality. The magnitude of these maxima increases by almost a factor of three between most peripheral and most central Pb-Pb collisions. This baryon excess at intermediate p(T) is not observed in pp interactions at √s=0.9 TeV and at √s=7 TeV. Qualitatively, the baryon enhancement in heavy-ion collisions is expected from radial flow. However, the measured p(T) spectra above 2 GeV/c progressively decouple from hydrodynamical-model calculations. For higher values of p(T), models that incorporate the influence of the medium on the fragmentation and hadronization processes describe qualitatively the p(T) dependence of the Λ/K(S)(0) ratio.

Charmonium and e+e- pair photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at [Formula: see text]

The ALICE Collaboration at the LHC has measured the J/ψ and ψ' photoproduction at mid-rapidity in ultra-peripheral Pb-Pb collisions at [Formula: see text]. The charmonium is identified via its leptonic decay for events where the hadronic activity is required to be minimal. The analysis is based on an event sample corresponding to an integrated luminosity of about 23 μb-1. The cross section for coherent and incoherent J/ψ production in the rapidity interval -0.9 Collapse

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Insulator-metal transition of VO₂ ultrathin films on silicon: evidence for an electronic origin by infrared spectroscopy

We report on the first simultaneous observations of both electronic and structural temperature-induced insulator-to-metal transition (IMT) in VO2 ultrathin films, made possible by the use of broad range transmission infrared spectroscopy. Thanks to these techniques, the infrared phonon structures, as well as the appearance of the free carrier signature, were resolved for the first time. The temperature-resolved spectra allowed the determination of the temperature hysteresis for both the structural (monoclinic-to-rutile) and electronic (insulator-to-metallic) transitions. The combination of these new observations and DFT simulations for the monoclinic structure allows us to verify the direct transition from monoclinic (M1) to rutile and exclude an intermediate structural monoclinic form (M2). The delay in structural modification compared to the primer electronic transition (325 K compared to 304 K) supports the role of free charges as the transition driving force. The shape of the free charge hysteresis suggests that the primer electronic transition occurs first at 304 K, followed by both its propagation to the heart of the layer and the structural transition when T increases. This study outlines further the potential of VO2 ultrathin films integrated on silicon for optoelectronics and microelectronics.

Investigation on fixed bed column performance of fluoride adsorption by sugarcane charcoal

The present study explores the potentiality of sugarcane charcoal for fluoride removal from synthetic fluoride solution. Column adsorption experiments with respect to variation of flow rate, pH, initial concentration, and column depths were carried out. Sugarcane charcoal exhibited almost consistent scavenging capacity at various bed depths with a flow rate 4.34 ml min(-1). Maximum adsorption capacity of sugarcane charcoal was recorded 7.33 mg g(-1). The adsorption studies were simulated using Thomas and Bed depth service time model. Both the models consistently predict its characteristic parameters and describe the breakthrough profiles in the whole range of sorption process.

Contralateral relapse after surgery for breast cancer: evaluation of follow-up paradigms

BACKGROUND

Early treatment of breast cancer patients with loco-regional relapse or contralateral disease has been shown to improve survival. There is no current consensus on the optimal follow-up strategy. This study estimates the risk of isolated contralateral relapse (CR) after breast cancer surgery and its change over time, together with the efficacy of clinical examination, self-examination and mammography in the detection of CR.

METHODS

Data from patients treated for early breast cancer at Guy's Hospital between 1990 and 1997 were collected and those with isolated contralateral recurrences were analysed. Life table analysis was performed and CR, CR-free and cumulative CR rates were calculated. Correlations were evaluated using Pearson's correlation coefficient.

RESULTS

One thousand one hundred and forty-three women were included in the study and 23 patients had isolated CR. The median probability of CR was a constant 0.24% per year. Only one recurrence was found clinically at follow up, while the majority was detected through mammography and self-palpation.

CONCLUSIONS

The risk of CR is low and constant with time. Contralateral mammography is useful and can detect the vast majority of contralateral recurrences. These findings may have practical implications especially on the planning of postmastectomy follow up.

J/ψ elliptic flow in Pb-Pb collisions at √(s(NN))=2.76 TeV

We report on the first measurement of inclusive J/ψ elliptic flow v2 in heavy-ion collisions at the LHC. The measurement is performed with the ALICE detector in Pb-Pb collisions at √(s(NN))=2.76 TeV in the rapidity range 2.5<y<4.0. The dependence of the J/ψ v2 on the collision centrality and on the J/ψ transverse momentum is studied in the range 0≤p(T)<10 GeV/c. For semicentral Pb-Pb collisions at √(s(NN))=2.76 TeV, an indication of nonzero v2 is observed with a largest measured value of v2=0.116±0.046(stat)±0.029(syst) for J/ψ in the transverse momentum range 2≤p(T)<4 GeV/c. The elliptic flow measurement complements the previously reported ALICE results on the inclusive J/ψ nuclear modification factor and favors the scenario of a significant fraction of J/ψ production from charm quarks in a deconfined partonic phase.

D meson elliptic flow in noncentral Pb-Pb collisions at sqrt[sNN]=2.76 Tev

Azimuthally anisotropic distributions of D0, D+, and D*+ mesons were studied in the central rapidity region (|y|<0.8) in Pb-Pb collisions at a center-of-mass energy sqrt[sNN]=2.76  TeV per nucleon-nucleon collision, with the ALICE detector at the LHC. The second Fourier coefficient v2 (commonly denoted elliptic flow) was measured in the centrality class 30%-50% as a function of the D meson transverse momentum pT, in the range 2-16  GeV/c. The measured v2 of D mesons is comparable in magnitude to that of light-flavor hadrons. It is positive in the range 2<pT<6  GeV/c with 5.7σ significance, based on the combination of statistical and systematic uncertainties.

Green fluorescent protein expression triggers proteome changes in breast cancer cells

Green fluorescent protein (GFP) is the most commonly used reporter of expression in cell biology despite evidence that it affects the cell physiology. The molecular mechanism of GFP-associated modifications has been largely unexplored. In this paper we investigated the proteome modifications following stable expression of GFP in breast cancer cells (MDA-MB-231). A combination of three different proteome analysis methods (2-DE, iTRAQ, label-free) was used to maximise proteome coverage. We found that GFP expression induces changes in expression of proteins that are associated with protein folding, cytoskeletal organisation and cellular immune response. In view of these findings, the use of GFP as a cell reporter should be carefully monitored.

Recovery of African horse sickness virus from synthetic RNA

African horse sickness virus (AHSV) is an insect-vectored emerging pathogen of equine species. AHSV (nine serotypes) is a member of the genus Orbivirus, with a morphology and coding strategy similar to that of the type member, bluetongue virus. However, these viruses are distinct at the genetic level, in the proteins they encode and in their pathobiology. AHSV infection of horses is highly virulent with a mortality rate of up to 90 %. AHSV is transmitted by Culicoides, a common European insect, and has the potential to emerge in Europe from endemic countries of Africa. As a result, a safe and effective vaccine is sought urgently. As part of a programme to generate a designed highly attenuated vaccine, we report here the recovery of AHSV from a complete set of RNA transcripts synthesized in vitro from cDNA clones. We have demonstrated the generation of mutant and reassortant AHSV genomes, their recovery, stable passage, and characterization. Our findings provide a new approach to investigate AHSV replication, to design AHSV vaccines and to aid diagnosis.

Measurement of inelastic, single- and double-diffraction cross sections in proton-proton collisions at the LHC with ALICE

Measurements of cross sections of inelastic and diffractive processes in proton-proton collisions at LHC energies were carried out with the ALICE detector. The fractions of diffractive processes in inelastic collisions were determined from a study of gaps in charged particle pseudorapidity distributions: for single diffraction (diffractive mass MX <200 GeV/c2) [Formula: see text], and [Formula: see text], respectively at centre-of-mass energies [Formula: see text]; for double diffraction (for a pseudorapidity gap Δη>3) σDD/σINEL=0.11±0.03,0.12±0.05, and [Formula: see text], respectively at [Formula: see text]. To measure the inelastic cross section, beam properties were determined with van der Meer scans, and, using a simulation of diffraction adjusted to data, the following values were obtained: [Formula: see text] mb at [Formula: see text] and [Formula: see text] at [Formula: see text]. The single- and double-diffractive cross sections were calculated combining relative rates of diffraction with inelastic cross sections. The results are compared to previous measurements at proton-antiproton and proton-proton colliders at lower energies, to measurements by other experiments at the LHC, and to theoretical models.

Net-charge fluctuations in Pb-Pb collisions at sqrt[sNN]=2.76 TeV

We report the first measurement of the net-charge fluctuations in Pb-Pb collisions at sqrt[sNN]=2.76  TeV, measured with the ALICE detector at the CERN Large Hadron Collider. The dynamical fluctuations per unit entropy are observed to decrease when going from peripheral to central collisions. An additional reduction in the amount of fluctuations is seen in comparison to the results from lower energies. We examine the dependence of fluctuations on the pseudorapidity interval, which may account for the dilution of fluctuations during the evolution of the system. We find that the fluctuations at the LHC are smaller compared to the measurements at the BNL Relativistic Heavy Ion Collider, and as such, closer to what has been theoretically predicted for the formation of a quark-gluon plasma.

THz magnetoelectric atomic rotations in the chiral compound Ba3NbFe3Si2O14

We have determined the terahertz spectrum of the chiral langasite Ba3NbFe3Si2O14 by means of synchrotron-radiation measurements. Two excitations are revealed that are shown to have a different nature. The first one, purely magnetic, is observed at low temperature in the magnetically ordered phase and is assigned to a magnon. The second one persists far into the paramagnetic phase and exhibits both an electric and a magnetic activity at slightly different energies. This magnetoelectric excitation is interpreted in terms of atomic rotations and requires a helical electric polarization.

Cellular phosphoinositides and the maturation of bluetongue virus, a non-enveloped capsid virus

Background

Bluetongue virus (BTV), a member of Orbivirus genus in the Reoviridae family is a double capsid virus enclosing a genome of 10 double-stranded RNA segments. A non-structural protein of BTV, NS3, which is associated with cellular membranes and interacts with outer capsid proteins, has been shown to be involved in virus morphogenesis in infected cells. In addition, studies have also shown that during the later stages of virus infection NS3 behaves similarly to HIV protein Gag, an enveloped viral protein. Since Gag protein is known to interact with membrane lipid phosphatidylinositol (4,5) bisphosphate [PI(4,5)P₂] and one of the known binding partners of NS3, cellular protein p11 also interacts with annexin a PI(4,5)P₂ interacting protein, this study was designed to understand the role of this negatively charged membrane lipid in BTV assembly and maturation.

Methods

Over expression of cellular enzymes that either depleted cells of PI(4,5)P₂ or altered the distribution of PI(4,5)P₂, were used to analyze the effect of the lipid on BTV maturation at different times post-infection. The production of mature virus particles was monitored by plaque assay. Microscopic techniques such as confocal microscopy and electron microscopy (EM) were also undertaken to study localization of virus proteins and virus particles in cells, respectively.

Results

Initially, confocal microscopic analysis demonstrated that PI(4,5)P₂ not only co-localized with NS3, but it also co-localized with VP5, one of the outer capsid proteins of BTV. Subsequently, experiments involving depletion of cellular PI(4,5)P₂ or its relocation demonstrated an inhibitory effect on normal BTV maturation and it also led to a redistribution of BTV proteins within the cell. The data was supported further by EM visualization showing that modulation of PI(4,5)P₂ in cells indeed resulted in less particle production.

Conclusion

This study to our knowledge, is the first report demonstrating involvement of PI(4,5)P₂ in a non-enveloped virus assembly and release. As BTV does not have lipid envelope, this finding is unique for this group of viruses and it suggests that the maturation of capsid and enveloped viruses may be more closely related than previously thought.

Coherent synchrotron radiation for broadband terahertz spectroscopy

We present the first high resolution (10(-3) cm(-1)) interferometric measurements in the 200-750 GHz range using coherent synchrotron radiation, achieved with a low momentum compaction factor. The effect of microbunching on spectra is shown, depending on the bunch current. A high signal-to-noise ratio is reached thanks to an artifact correction system based on a double detection scheme. Combined to the broad emitted spectral range and high flux (up to 10(5) times the incoherent radiation), this study demonstrates that coherent synchrotron radiation can now be used for stability-demanding applications, such as gas-phase studies of unstable molecules.

Transverse momentum distribution and nuclear modification factor of charged particles in p+Pb collisions at sqrt[s(NN)] = 5.02 TeV

The transverse momentum (p(T)) distribution of primary charged particles is measured in minimum bias (non-single-diffractive) p+Pb collisions at sqrt[s(NN)]=5.02 TeV with the ALICE detector at the LHC. The p(T) spectra measured near central rapidity in the range 0.5<p(T) <20 GeV/c exhibit a weak pseudorapidity dependence. The nuclear modification factor R(pPb) is consistent with unity for p(T) above 2 GeV/c. This measurement indicates that the strong suppression of hadron production at high p(T) observed in Pb+Pb collisions at the LHC is not due to an initial-state effect. The measurement is compared to theoretical calculations.

Pseudorapidity density of charged particles in p+Pb collisions at √(s(NN))=5.02 TeV

The charged-particle pseudorapidity density measured over four units of pseudorapidity in nonsingle-diffractive p+Pb collisions at a center-of-mass energy per nucleon pair √(s(NN))=5.02 TeV is presented. The average value at midrapidity is measured to be 16.81±0.71 (syst), which corresponds to 2.14±0.17 (syst) per participating nucleon, calculated with the Glauber model. This is 16% lower than in nonsingle-diffractive pp collisions interpolated to the same collision energy and 84% higher than in d+Au collisions at s√(s(NN))=0.2 TeV. The measured pseudorapidity density in p+Pb collisions is compared to model predictions and provides new constraints on the description of particle production in high-energy nuclear collisions.

Charge separation relative to the reaction plane in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV

Measurements of charge-dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudorapidity range |η| < 0.8 are presented as a function of the collision centrality, particle separation in pseudorapidity, and transverse momentum. A clear signal compatible with a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. This provides a new insight for understanding the nature of the charge-dependent azimuthal correlations observed at RHIC and LHC energies.

Immunization against active ghrelin using virus-like particles for obesity treatment

Ghrelin is a gut hormone that stimulates food intake. In physiological conditions, ghrelin plasma levels rise with fasting and decrease after meals. Obese individuals have low fasting ghrelin levels that rise after food restriction, which is pointed out as a reason for the difficulty in maintaining weight loss. Some bariatric surgery procedures prevent rise in ghrelin levels with weight loss and this has been hypothesised to contribute to the long-term success of the treatment. The main goal of this study was to develop a safe and effective anti-ghrelin vaccine for obesity, through the chemical conjugation of ghrelin with a virus like particle, namely NS1 protein tubules from the Bluetongue Virus (BTV) using a hetero-bifunctional cross linker. Male adult C57BL/6 mice, with a normal weight and with diet-induced obesity (DIO), were randomized into six weight matched groups (n=6/group) and each group of mice received three intra-peritoneal injections with two weeks intervals, containing either 75 μg of ghrelin- NS1 immunoconjugate, 75 μg of NS1 or PBS. Our data show that immunized animals present increasing titres of anti-ghrelin antibodies, while their cumulative food intake significantly decreased and energy expenditure was significantly enhanced, although there were no significative changes in body weight.Vaccinated DIO mice also displayed significant decrease of NPY gene expression in the basal hypothalamus reflecting a decrease in central orexigenic signals. This study suggests that this anti-ghrelin vaccine has a positive impact on energy homeostasis and may be an additional therapeutical tool to be used with diet and exercise for obesity treatment.

Pion, kaon, and proton production in central Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV

In this Letter we report the first results on π(±), K(±), p, and p production at midrapidity (|y|<0.5) in central Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV, measured by the ALICE experiment at the LHC. The p(T) distributions and yields are compared to previous results at sqrt[s(NN)] = 200 GeV and expectations from hydrodynamic and thermal models. The spectral shapes indicate a strong increase of the radial flow velocity with sqrt[s(NN)], which in hydrodynamic models is expected as a consequence of the increasing particle density. While the K/π ratio is in line with predictions from the thermal model, the p/π ratio is found to be lower by a factor of about 1.5. This deviation from thermal model expectations is still to be understood.

Measurement of the cross section for electromagnetic dissociation with neutron emission in Pb-Pb collisions at sqrt[s(NN)] = 2.76 TeV

The first measurement of neutron emission in electromagnetic dissociation of ^{208}Pb nuclei at the LHC is presented. The measurement is performed using the neutron zero degree calorimeters of the ALICE experiment, which detect neutral particles close to beam rapidity. The measured cross sections of single and mutual electromagnetic dissociation of Pb nuclei at sqrt[s(NN)]=2.76 TeV with neutron emission are σ(singleEMD)=187.4 ± 0.2(stat)(-11.2)(+13.2) (syst) b and σ(mutualEMD) = 5.7 ± 0.1(stat) ± 0.4(syst) b, respectively. The experimental results are compared to the predictions from a relativistic electromagnetic dissociation model.

Bluetongue virus serotype 8 virus-like particles protect sheep against virulent virus infection as a single or multi-serotype cocktail immunogen

Since 1998, there have been multiple separate outbreaks of Bluetongue disease (BT) in Europe with the largest outbreak ever recorded in Northern Europe caused by Bluetongue virus serotype 8 (BTV-8). Coinciding with the BTV-8 outbreak, a virulent strain of BTV-1 emerged and co-infections of these two serotypes were reported. In response, we generated VLPs for BTV-8 and tested the efficacy of BTV-8 VLPs as a single immunogen and as a component of a multivalent vaccine, with VLPs of BTV-1 and BTV-2, in order to test if there was any interference between serotypes. All pre-Alps sheep vaccinated with BTV-8 VLPs developed a strong neutralising antibody response to BTV-8 and multivalent VLP vaccinated animals also developed neutralising antibodies to BTV-1 and BTV-2. There were no side effects observed due to the vaccination with either the single- or multivalent VLP cocktail. All VLP-vaccinated animals had no clinical manifestation of BT or viraemia after challenge with a virulent BTV-8 isolate. This data indicates that BTV-8 VLPs delivered as a single immunogen or as a component of a multivalent vaccine are highly efficacious. Moreover, there was no interference on the development of a strong protective immune response due to the combination of different phylogenetically unrelated BTV serotypes in the vaccinated animals. This report further highlights that BTV VLPs are safe and efficacious immunogens that are able to afford complete protection against a virulent virus challenge.

Production of muons from heavy flavor decays at forward rapidity in pp and Pb-Pb collisions at sqrt[s(NN)]=2.76 TeV

The ALICE Collaboration has measured the inclusive production of muons from heavy-flavor decays at forward rapidity, 2.5<y<4, in pp and Pb-Pb collisions at sqrt[s(NN)]=2.76  TeV. The p(t)-differential inclusive cross section of muons from heavy-flavor decays in pp collisions is compared to perturbative QCD calculations. The nuclear modification factor is studied as a function of p(t) and collision centrality. A weak suppression is measured in peripheral collisions. In the most central collisions, a suppression of a factor of about 3-4 is observed in 6<p(t)<10  GeV/c. The suppression shows no significant p(t) dependence.

Use of bacterial artificial chromosomes in baculovirus research and recombinant protein expression: current trends and future perspectives

The baculovirus expression system is one of the most successful and widely used eukaryotic protein expression methods. This short review will summarise the role of bacterial artificial chromosomes (BACS) as an enabling technology for the modification of the virus genome. For many years baculovirus genomes have been maintained in E. coli as bacterial artificial chromosomes, and foreign genes have been inserted using a transposition-based system. However, with recent advances in molecular biology techniques, particularly targeting reverse engineering of the baculovirus genome by recombineering, new frontiers in protein expression are being addressed. In particular, BACs have facilitated the propagation of disabled virus genomes that allow high throughput protein expression. Furthermore, improvement in the selection of recombinant viral genomes inserted into BACS has enabled the expression of multiprotein complexes by iterative recombineering of the baculovirus genome.

Bluetongue virus non-structural protein 1 is a positive regulator of viral protein synthesis

Background

Bluetongue virus (BTV) is a double-stranded RNA (dsRNA) virus of the Reoviridae family, which encodes its genes in ten linear dsRNA segments. BTV mRNAs are synthesised by the viral RNA-dependent RNA polymerase (RdRp) as exact plus sense copies of the genome segments. Infection of mammalian cells with BTV rapidly replaces cellular protein synthesis with viral protein synthesis, but the regulation of viral gene expression in the Orbivirus genus has not been investigated.

Results

Using an mRNA reporter system based on genome segment 10 of BTV fused with GFP we identify the protein characteristic of this genus, non-structural protein 1 (NS1) as sufficient to upregulate translation. The wider applicability of this phenomenon among the viral genes is demonstrated using the untranslated regions (UTRs) of BTV genome segments flanking the quantifiable Renilla luciferase ORF in chimeric mRNAs. The UTRs of viral mRNAs are shown to be determinants of the amount of protein synthesised, with the pre-expression of NS1 increasing the quantity in each case. The increased expression induced by pre-expression of NS1 is confirmed in virus infected cells by generating a replicating virus which expresses the reporter fused with genome segment 10, using reverse genetics. Moreover, NS1-mediated upregulation of expression is restricted to mRNAs which lack the cellular 3^′ poly(A) sequence identifying the 3^′ end as a necessary determinant in specifically increasing the translation of viral mRNA in the presence of cellular mRNA.

Conclusions

NS1 is identified as a positive regulator of viral protein synthesis. We propose a model of translational regulation where NS1 upregulates the synthesis of viral proteins, including itself, and creates a positive feedback loop of NS1 expression, which rapidly increases the expression of all the viral proteins. The efficient translation of viral reporter mRNAs among cellular mRNAs can account for the observed replacement of cellular protein synthesis with viral protein synthesis during infection.

J/ψ suppression at forward rapidity in Pb-Pb collisions at √s(NN) = 2.76 TeV

The ALICE experiment has measured the inclusive J/ψ production in Pb-Pb collisions at √s(NN) = 2.76 TeV down to zero transverse momentum in the rapidity range 2.5 < y < 4. A suppression of the inclusive J/ψ yield in Pb-Pb is observed with respect to the one measured in pp collisions scaled by the number of binary nucleon-nucleon collisions. The nuclear modification factor, integrated over the 0%-80% most central collisions, is 0.545 ± 0.032(stat) ± 0.083(syst) and does not exhibit a significant dependence on the collision centrality. These features appear significantly different from measurements at lower collision energies. Models including J/ψ production from charm quarks in a deconfined partonic phase can describe our data.

Rift Valley fever: Real or perceived threat for Zambia?

Rift Valley fever (RVF) in Zambia was first reported in 1974 during an epizootic of cattle and sheep that occurred in parts of Central, Southern and Copperbelt Provinces. In 1990, the disease was documented in nine districts of the provinces of Zambia. In the last two decades, there have been no reports of RVF. This long period without reported clinical disease raises questions as to whether RVF is a current or just a perceived threat. To address this question, World Organisation for Animal Health (OIE) disease occurrence data on RVF for the period 2005−2010 in the Southern Africa Development Community (SADC) was analysed. From the analysis, it was evident that most countries that share a common border with Zambia had reported at least one occurrence of the disease during the period under review. Due to the absence of natural physical barriers between Zambia and most of her neighbours, informal livestock trade and movements is a ubiquitous reality. Analysis of the rainfall patterns also showed that Zambia received rains sufficient to support a mosquito population large enough for high risk of RVF transmission. The evidence of disease occurrence in nearby countries coupled with animal movement, and environmental risk suggests that RVF is a serious threat to Zambia. In conclusion, the current occurrence of RVF in Zambia is unclear, but there are sufficient indications that the magnitude of the circulating infection is such that capacity building in disease surveillance and courses on recognition of the disease for field staff is recommended. Given the zoonotic potential of RVF, these measures are also a prerequisite for accurate assessment of the disease burden in humans.

A rare case of allergic bronchopulmonary mycosis caused by Alternaria alternata

A rare case of allergic bronchopulmonary mycosis (ABPM), caused by Alternaria alternata, is reported in an immunocompetent resident of Delhi. Her complaints included a generalized, urticarial skin rash and occasional pain in the right lower chest. Her differential count showed eosinophils, 22%; absolute eosinophil count (AEC), 2400 cells/μl; and total IgE, 4007 IU/ml. The computerised tomogram (CT) scan of her thorax showed an enhancing lesion with surrounding ground glass haziness in the right lower lobe. Histopathologic examination of the resected lung revealed a necrotizing granulomatous inflammation, parenchymal infiltration by eosinophils, lymphocytes, neutrophils, plasma cells and some exudative bronchiolitis suggestive of ABPM. Observation of KOH wet mounts of repeat sputum and BAL samples demonstrated the presence of septate, brownish hyphae and cultures of these specimens yielded A. alternata (identified by sequencing of the ITS region). Her serum showed a three-fold higher specific IgE to A. alternata antigens than control levels, and the type I cutaneous hypersensitivity response to antigens of A. alternata was strongly positive. She was treated successfully with oral glucocorticoids and itraconazole. To our knowledge, ABPM due to Alternaria alternata has not been reported previously.

The double-stranded RNA bluetongue virus induces type I interferon in plasmacytoid dendritic cells via a MYD88-dependent TLR7/8-independent signaling pathway

Dendritic cells (DCs), especially plasmacytoid DCs (pDCs), produce large amounts of alpha/beta interferon (IFN-α/β) upon infection with DNA or RNA viruses, which has impacts on the physiopathology of the viral infections and on the quality of the adaptive immunity. However, little is known about the IFN-α/β production by DCs during infections by double-stranded RNA (dsRNA) viruses. We present here novel information about the production of IFN-α/β induced by bluetongue virus (BTV), a vector-borne dsRNA Orbivirus of ruminants, in sheep primary DCs. We found that BTV induced IFN-α/β in skin lymph and in blood in vivo. Although BTV replicated in a substantial fraction of the conventional DCs (cDCs) and pDCs in vitro, only pDCs responded to BTV by producing a significant amount of IFN-α/β. BTV replication in pDCs was not mandatory for IFN-α/β production since it was still induced by UV-inactivated BTV (UV-BTV). Other inflammatory cytokines, including tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and IL-12p40, were also induced by UV-BTV in primary pDCs. The induction of IFN-α/β required endo-/lysosomal acidification and maturation. However, despite being an RNA virus, UV-BTV did not signal through Toll-like receptor 7 (TLR7) for IFN-α/β induction. In contrast, pathways involving the MyD88 adaptor and kinases dsRNA-activated protein kinase (PKR) and stress-activated protein kinase (SAPK)/Jun N-terminal protein kinase (JNK) were implicated. This work highlights the importance of pDCs for the production of innate immunity cytokines induced by a dsRNA virus, and it shows that a dsRNA virus can induce IFN-α/β in pDCs via a novel TLR-independent and Myd88-dependent pathway. These findings have implications for the design of efficient vaccines against dsRNA viruses.

Schizophyllum commune as an emerging fungal pathogen: a review and report of two cases

We report Schizophyllum commune as the aetiological agent of one case each of allergic broncho-pulmonary mycosis (ABPM) and pulmonary fungal ball, and present a literature review. The fungus was characterised by clamp connections, hyphal spicules, and formation of basidiocarps with basidiospores. The phenotypic identification was confirmed by sequencing of the ITS region. To-date, ABPM and pulmonary fungal ball to S. commune have been reported exclusively from Japan and North America respectively. Of the 71 globally reported cases due to S. commune, 45 (63%) were bronchopulmonary, 22 (31%) sinusitis and 4 extrapulmonary. Taken together, cases of bronchopulmonary disease and sinusitis numbered 67 (94%), indicating the respiratory tract as the primary target of disease. Concerning the country-wise distribution, Japan topped the list with 33 cases (46%), followed by Iran - 7 cases (10%), U.S.A. - 6 cases (9%), and a lower prevalence of 1.4-6% for the remaining 12 countries. The preponderance of the disease in Japan may be attributed to its greater awareness vis-à-vis that in other countries rather than to any geographical/climatic factors. We believe that the burden of S. commune-incited disease is currently underestimated, warranting comprehensive prospective studies to determine its prevalence.

Particle-yield modification in jetlike azimuthal dihadron correlations in Pb-Pb collisions at √s(NN)=2.76 TeV

The yield of charged particles associated with high-p(t) trigger particles (8<p(t)<15 GeV/c) is measured with the ALICE detector in Pb-Pb collisions at √s(NN)=2.76 TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jetlike correlation peaks in azimuthal dihadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta p(t)>3 GeV/c on the away side drops to about 60% of that observed in pp collisions, while on the near side a moderate enhancement of 20%-30% is found.

J/ψ polarization in pp collisions at √s=7 TeV

The ALICE Collaboration has studied J/ψ production in pp collisions at √s=7 TeV at the LHC through its muon pair decay. The polar and azimuthal angle distributions of the decay muons were measured, and results on the J/ψ polarization parameters λ(θ) and λ(φ) were obtained. The study was performed in the kinematic region 2.5<y<4, 2<p(t)<8 GeV/c, in the helicity and Collins-Soper reference frames. In both frames, the polarization parameters are compatible with zero, within uncertainties.

Protective efficacy of Bluetongue virus-like and subvirus-like particles in sheep: presence of the serotype-specific VP2, independent of its geographic lineage, is essential for protection

There have been multiple separate outbreaks of Bluetongue (BT) disease of ruminants in Europe since 1998, often entering via the Mediterranean countries of Italy, Spain and Greece. BT is caused by an orbivirus, Bluetongue virus (BTV), a member of the family Reoviridae. BTV is a non-enveloped double-capsid virus, which encodes 7 structural proteins (VP1-VP7) and several non-structural proteins (NS1, NS2, NS3/3a and NS4) from ten double-stranded RNA segments of the genome. In this report, we have prepared BTV virus-like particles (VLPs, composed of VP2, VP3, VP5 and VP7) and sub-viral, inner core-like particles (CLPs, VP3 and VP7) using a recombinant baculovirus expression system. We compared the protective efficacy of VLPs and CLPs in sheep and investigated the importance of geographical lineages of BTV in the development of vaccines. The Greek crossbred Karagouniko sheep, which display mild to sub-clinical BT, were vaccinated with VLPs or CLPs of BTV-1, derived from western lineage and were challenged with virulent BTV-1 from an eastern lineage. All VLP-vaccinated animals developed a neutralising antibody response to BTV-1 from both lineages prior to challenge. Moreover, post-challenged animals had no clinical manifestation or viraemia and the challenged virus replication was completely inhibited. In contrast, CLP-vaccinated animals did not induce any neutralising antibody response but developed the group specific VP7 antibodies. CLPs also failed to prevent the clinical manifestation and virus replication, but in comparison to controls, the severity of disease manifestation and viraemia was mitigated. The data demonstrated that the outer capsid was essential for complete protection, while the geographical origin of the BTV was not critical for development of a serotype specific vaccine.

Bluetongue virus VP1 polymerase activity in vitro: template dependency, dinucleotide priming and cap dependency

BACKGROUND

Bluetongue virus (BTV) protein, VP1, is known to possess an intrinsic polymerase function, unlike rotavirus VP1, which requires the capsid protein VP2 for its catalytic activity. However, compared with the polymerases of other members of the Reoviridae family, BTV VP1 has not been characterized in detail.

METHODS AND FINDINGS

Using an in vitro polymerase assay system, we demonstrated that BTV VP1 could synthesize the ten dsRNAs simultaneously from BTV core-derived ssRNA templates in a single in vitro reaction as well as genomic dsRNA segments from rotavirus core-derived ssRNA templates that possess no sequence similarity with BTV. In contrast, dsRNAs were not synthesized from non-viral ssRNA templates by VP1, unless they were fused with specific BTV sequences. Further, we showed that synthesis of dsRNAs from capped ssRNA templates was significantly higher than that from uncapped ssRNA templates and the addition of dinucleotides enhanced activity as long as the last base of the dinucleotide complemented the 3' -terminal nucleotide of the ssRNA template.

CONCLUSIONS

We showed that the polymerase activity was stimulated by two different factors: cap structure, likely due to allosteric effect, and dinucleotides due to priming. Our results also suggested the possible presence of cis-acting elements shared by ssRNAs in the members of family Reoviridae.

High resolution far-infrared Fourier transform spectroscopy of radicals at the AILES beamline of SOLEIL synchrotron facility

Experimental far-infrared (FIR) spectroscopy of transient species (unstable molecules, free radicals, and ions) has been limited so far in both emission and absorption (mainly by the low probability of spontaneous emission in that spectral range and the low brightness of continuum sources used for absorption measurements, respectively). Nevertheless, the FIR spectral range recently became of high astrophysical relevance thanks to several new observational platforms (HERSCHEL, ALMA...) dedicated to the study of this region suitable for the detection of the emission from cold objects of the interstellar medium. In order to complete the experimental dataset concerning transient species, three discharge experiments dedicated to the recording of high resolution FIR spectra of radicals have been developed at the Advanced Infrared Line Exploited for Spectroscopy (AILES) which extracts the bright FIR synchrotron continuum of the synchrotron facility SOLEIL. These experiments make use of a high resolution (R = 0.001 cm(-1)) Bruker IFS125 Fourier transform (FT) spectrometer. An emission setup (allowing to record spectra of radicals excited at high rotational and vibrational temperatures) and two absorption setups (exploiting the bright synchrotron source at the highest resolution available on the FT) are alternatively connected to the FT. The advantages and limitations of these techniques are discussed on the basis of the recent results obtained on OH and CH radicals. These results constitute the first FIR spectra of radicals using synchrotron radiation, and the first FIR spectrum of a C-bearing radical using FT-spectroscopy.

Generation of replication-defective virus-based vaccines that confer full protection in sheep against virulent bluetongue virus challenge

The reverse genetics technology for bluetongue virus (BTV) has been used in combination with complementing cell lines to recover defective BTV-1 mutants. To generate a potential disabled infectious single cycle (DISC) vaccine strain, we used a reverse genetics system to rescue defective virus strains with large deletions in an essential BTV gene that encodes the VP6 protein (segment S9) of the internal core. Four VP6-deficient BTV-1 mutants were generated by using a complementing cell line that provided the VP6 protein in trans. Characterization of the growth properties of mutant viruses showed that each mutant has the necessary characteristics for a potential vaccine strain: (i) viral protein expression in noncomplementing mammalian cells, (ii) no infectious virus generated in noncomplementing cells, and (iii) efficient replication in the complementing VP6 cell line. Further, a defective BTV-8 strain was made by reassorting the two RNA segments that encode the two outer capsid proteins (VP2 and VP5) of a highly pathogenic BTV-8 with the remaining eight RNA segments of one of the BTV-1 DISC viruses. The protective capabilities of BTV-1 and BTV-8 DISC viruses were assessed in sheep by challenge with specific virulent strains using several assay systems. The data obtained from these studies demonstrated that the DISC viruses are highly protective and could offer a promising alternative to the currently available attenuated and killed virus vaccines and are also compliant as DIVA (differentiating infected from vaccinated animals) vaccines.

Higher harmonic anisotropic flow measurements of charged particles in Pb-Pb collisions at sqrt(s(NN)) = 2.76 TeV

We report on the first measurement of the triangular v3, quadrangular v4, and pentagonal v5 charged particle flow in Pb-Pb collisions at sqrt(s(NN)) = 2.76  TeV measured with the ALICE detector at the CERN Large Hadron Collider. We show that the triangular flow can be described in terms of the initial spatial anisotropy and its fluctuations, which provides strong constraints on its origin. In the most central events, where the elliptic flow v2 and v3 have similar magnitude, a double peaked structure in the two-particle azimuthal correlations is observed, which is often interpreted as a Mach cone response to fast partons. We show that this structure can be naturally explained from the measured anisotropic flow Fourier coefficients.

Highly birefringent photonic bandgap Bragg fiber loop mirror for simultaneous measurement of strain and temperature

A highly birefringent photonic bandgap Bragg fiber loop mirror configuration for simultaneous measurement of strain and temperature is proposed. The group birefringence and the sharp loss peaks are observable in the spectral response. Because the sensing head presents different sensitivities for strain and temperature measurands, these physical parameters can be discriminated by using the matrix method. It should be noted that this Bragg fiber presents high sensitivity to temperature, of ∼5.75 nm/°C, due to the group birefringence variation. The rms deviations obtained are ±19.32 με and ±0.5 °C, for strain and temperature measurements, respectively.