•A sturgeon NCLDV was reported in European sturgeon mortality outbreaks.•Acinetobacter spp. was evidenced in sturgeon mortality outbreaks in Europe.•The relationship between European and North ...American sturgeon NCLDVs was defined.•A NCLDV persistent subclinical infection was evidenced in survivor sturgeons.•A NCLDV systemic infection was suspected in diseased and survivor sturgeons.
Diseased outbreaks with high mortality in farmed sturgeon are a limiting factor to the success of this emerging aquaculture sector in Europe. Thorough investigations of outbreaks can determine the aetiological agents, identify important pathological and epidemiological pathways of infections and pave the way for effective control strategies.
A thorough investigation of a mortality outbreak in Russian (Acipenser gueldenstaedtii) and Siberian (Acipenser baerii) sturgeons in Italy, demonstrated the primary involvement of a sturgeon nucleo-cytoplasmic large DNA virus (NCLDV). While, the taxonomy classification of this new virus is still uncertain, its involvement in sturgeon mortality outbreaks in Europe is, for the first time, fully investigated and described. Furthermore, the coinfection of bacteria such as motile Aeromonas spp. and Acinetobacter spp. was reported.
Genetic characterisation showed the close relationship between the European sturgeon NCLDV with North American sturgeon NCLDVs. Similarly to the latter, the European sturgeon NCLDV persists in survivors. Furthermore, a systemic distribution of the European sturgeon NCLDV was evident in diseased A. baerii and A. gueldenstaedtii and in recovered A. gueldenstaedtii.
These epidemiological and pathological findings will help in the identification of effective control strategies for sturgeon NCLDV infection, which afflicts an important and emerging European aquaculture sector.
A review of direct bounds on the mass of the tau neutrino obtained at the LEP collider is presented. In addition to published results it includes preliminary results presented at recent conferences ...and new results presented at the 1996 Tau Workshop. The different techniques and decay modes employed by the ALEPH, DELPHI and OPAL collaborations are compared. The impact of the theoretical modelling of tau decays is also discussed.
The most stringent 95% CL limit on the tau neutrino mass is now obtained by a preliminary ALEPH analysis which combines the results from τ → 5π
±(π
0)ν
τ and τ → 3π
± ν
τ decays. This bound constraints the mass of the tau neutrino below 18.2
MeV/c
2
.
The purpose of this narrative case study was to examine the motivation and challenges faced by the founding members of a K-8 progressive independent school in a rural Northern California community in ...2006 as they sought to establish an alternative option for educating its students. As a result of the study, four themes emerged: 1. There was a perceived need for a K-8 school of higher-quality education in the community. 2. The founders wanted to ensure that students would be supported by strong, healthy, caring relationships with their teachers. 3. The founders believed in creating a more constructive, learner-centered approach for children in an alternative school environment. 4. In considering the creation of a new school, the founders referenced the desire to design an organizational culture that would support a sense of community and value emotional and social well-being and character development. The concluding analysis revealed the three major findings in this study: 1.The founding members questioned the continued philosophy, educational policies, and practices promoted by the National and State Education Departments that shared history with little significant change over many decades and were concerned about how these were impacting our children in the local public school system and other schools in this community. 2. Community members, parents, and teachers have observed and experienced education alternatives in other parts of the country and world compared to what the schools are offering in this community. They felt compelled to create a different model that they believed offered more in the best interest of our children.3. Founding parents, community members, and educators could see a need for a new school environment in this community that would employ the best pedagogical theories and practices
We have measured the cross section σ(e+e−→π+π−γ) at an energy W=mϕ=1.02 GeV with the KLOE detector at the electron–positron collider DAΦNE. From the dependence of the cross section on the invariant ...mass of the two-pion system, we extract σ(e+e−→π+π−) for the mass range 0.35<s<0.95 GeV2. From this result, we calculate the pion form factor and the hadronic contribution to the muon anomaly, aμ.
The tracking detector of the KLOE experiment Adinolfi, M; Ambrosino, F; Andryakov, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2002, Letnik:
488, Številka:
1
Journal Article
Recenzirano
The design and construction of the large Drift Chamber for the KLOE experiment at the Frascati φ-factory, DAΦNE, are described. The relevant aspects of the various elements of the detector are ...reviewed together with a description of the track reconstruction program and of the calibration procedures. The performance of the detector based on measurements with cosmic rays and with e
+e
− colliding beams during DAΦNE commissioning is presented.
The KLOE electromagnetic calorimeter Adinolfi, M; Ambrosino, F; Antonelli, A ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2002, Letnik:
482, Številka:
1-2
Journal Article
Recenzirano
The KLOE detector was designed primarily for the study of CP violation in neutral kaon decays at DAΦNE, the Frascati φ-factory. The detector consists of a tracker and an electromagnetic calorimeter. ...A lead-scintillating-fiber sampling calorimeter satisfies best the requirements of the experiment, providing adequate energy resolution and superior timing accuracy. We describe in the following the construction of the calorimeter, its calibration and how the calorimeter information is used to obtain energy, point of entry and time of the arrival of photons, electrons and charged particles. With e+e− collision data at DAΦNE for an integrated luminosity of some 2pb−1 we find for electromagnetic showers, an energy resolution of 5.7%/E(GeV) and a time resolution of 54/E(GeV) ps. We also present a measurement of efficiency for low energy photons.
Data handling, reconstruction, and simulation for the KLOE experiment Ambrosino, F.; Antonelli, A.; Antonelli, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2004, Letnik:
534, Številka:
3
Journal Article
Recenzirano
Odprti dostop
The broad physics program of the KLOE experiment is based on the high event rate at the Frascati φ
factory, and calls for an up-to-date system for data acquisition and processing. In this review of ...the KLOE offline environment, the architecture of the data-processing system and the programs developed for data reconstruction and Monte Carlo simulation are described, as well as the various procedures used for data handling and transfer between the different components of the system.
The trigger system of the KLOE experiment Adinolfi, M; Ambrosino, F; Antonelli, M ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2002, Letnik:
492, Številka:
1
Journal Article
Recenzirano
Odprti dostop
We present the design of the trigger system for the KLOE experiment at the Frascati
φ-factory DAΦNE. The detector consists of a large-volume drift chamber and a calorimeter both immersed in a
0.52
T
...solenoidal field. The trigger, structured with a first- and a second-decision level, is based on the multiplicity of energy deposits in the calorimeter and of hits in the drift chamber. The selection criteria are described and the efficiency for detecting
φ decays is evaluated using data.
For the first time an electrostatic method of wire tension measurement (WTM) is used for drift chamber construction. It became possible due to the use of a digital approach to sense the wire ...oscillations induced by an alternating potential. The method has excellent signal-to-noise ratio, high accuracy which is well above the stringing requirements and reasonable measuring time. The WTM system implemented in a CAMAC–Machintosh–Labview environment is now in use for the KLOE drift chamber stringing control and for monitoring the end-plate deformation.
We have measured the radiative decays
φ→
ηγ,
φ→
η′
γ selecting
π
+
π
−
γγγ final state in a sample of ∼5×10
7
φ-mesons produced at the Frascati
φ-factory DA
ΦNE. We obtain
Γ(
φ→
η′
γ)/
Γ(
φ→
...ηγ)=(4.70±0.47±0.31)×10
−3. From this result we derive new accurate values for the branching ratio BR(
φ→
η′
γ)=(6.10±0.61±0.43)×10
−5 and the mixing angle of pseudoscalar mesons in the flavour basis
ϕ
P
=(41.8
+1.9
−1.6)°.
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