The scattering of dark matter (DM) particles with sub-GeV masses off nuclei is difficult to detect using liquid xenon-based DM search instruments because the energy transfer during nuclear recoils is ...smaller than the typical detector threshold. However, the tree-level DM-nucleus scattering diagram can be accompanied by simultaneous emission of a bremsstrahlung photon or a so-called "Migdal" electron. These provide an electron recoil component to the experimental signature at higher energies than the corresponding nuclear recoil. The presence of this signature allows liquid xenon detectors to use both the scintillation and the ionization signals in the analysis where the nuclear recoil signal would not be otherwise visible. We report constraints on spin-independent DM-nucleon scattering for DM particles with masses of 0.4-5 GeV/c^{2} using 1.4×10^{4} kg day of search exposure from the 2013 data from the Large Underground Xenon (LUX) experiment for four different classes of mediators. This analysis extends the reach of liquid xenon-based DM search instruments to lower DM masses than has been achieved previously.
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Beltrame APCA, Triches TC, Sartori N, Bolan M. Electronic determination of root canal working length in primary molar teeth: an in vivo and ex vivo study. International Endodontic Journal, 44, ...402–406, 2011.
Aim To evaluate in vivo and ex vivo the accuracy of an electronic apex locator in primary molar teeth with or without root resorption.
Methodology Fifteen primary molar teeth with 30 root canals were divided into two groups: roots without resorption (n = 13) and roots with resorption (n = 17). Root canals were measured with the Root ZX apex locator in vivo, and then after tooth extraction, each canal was measured electronically ex vivo. The actual root canal length was measured visually, with the placement of a K‐file into the most cervical edge of either apical foramen or resorption. The Student’s t‐test was applied for statistical analysis at a 5% significance level.
Results The electronic apex locator was precise in 69% and 65% of the cases with and without root resorption, respectively (tolerance = ±0.5 mm), in vivo and 69% and 77%ex vivo. When the tolerance was ±1 mm, however, these figures increased to 92% and 94% for root canals with and without resorption, respectively, in vivo and ex vivo. No significant difference was observed between the resorbed and non‐resorbed root canals measured using the Root ZX.
Conclusion The Root ZX apex locator was accurate in determining in vivo and ex vivo the working length ±1 mm in primary molar teeth in over 90% of roots regardless of the presence of root resorption.
Reactive lymphocytosis can be difficult to differentiate from clonal lymphocytosis, especially when it involves CD8 positive T-lymphocytes. Leukemias and lymphomas cause an increase in this ...population at the expense of replication of clonal cells with genetic and/or phenotypic aberrations. Infections, mainly of viral etiology, often cause an exacerbated response of this population. The expansion resulting from a viral infection is not selective, so multiple cell clones are involved. Defining the cause of lymphocytosis is essential for determining therapeutic measures.
To define T-cell clonality in patients with peripheral blood lymphocytosis using TCR Vβ2 repertoire by flow cytometry multiparametric analysis (FCM).
We included five patients with suspected T-cell lymphocytosis, one patient with immunodeficiency, and one control. Analysis of TCR Vβ2 rearrangements was performed on whole blood sample using the IOTest Beta Mark TCR Vβ Repertoire Kit (IOTest, Beckman Coulter, Indianapolis, USA) antibody set. BD FACSCantoTM II Cytometer and InfinicytTM 2.0 analysis software were used.
Patient 1 was considered as negative control (lymphocytes 3.41x103/μL) showed expression of various Vβ2 clones, ranging from 0.05 to 1.40%. Patients 2 and 3, both increased CD8 T-lymphocytes associated with a history of infectious disease, had a polyclonal profile of TCR Vβ2 expression, Patient 4 had lymphocytosis (4.25x103/μl) with majority expression of Vβ5.1 clones on CD4 (10.84%) and CD8 (10.56%) lymphocytes and of Vβ 13.2 clone on CD4 lymphocytes (11.53%). This patient was considered with reactive oligoclonal proliferation. Patient 5 had lymphocytosis with an abnormal CD8 T cell phenotype suggestive of Large Granular T-Cell Leukemia. TCR rearrangement analysis confirmed the presence of the Vβ 13.1 clone in CD8 T-cells. Patient 6 had a large lymphocytosis (462.92x103/μL) with a predominance of CD8 positive T-cells and a phenotype suggestive of Prolymphocytic T Cell Leukemia. TCR rearrangement indicated the majority presence of the Vβ8 clone on CD8 T-cell. And finally, patient 7 had mild lymphocytosis (6.87x103/μL) with a predominance of CD8 T-cells with expression of clone Vβ 4 (8.90%) and Vβ17 (2.01%) and of clone Vβ3 on CD4 cells (6.51%) and was considered as oligoclonal expansion.
The confirmation of monoclonal expansion of CD8 T lymphocytes could help in the diagnosis of T-cell neoplasms, confirming the diagnosis of large granular T-cell leukemia and CD8 T-cell prolymphocytic leukemia in two patients. Among the patients with polyclonal or oligoclonal expression, all patients had a history of viral infectious diseases, such as CMV or EBV infection. Patient 7 had a diagnosis of immunodeficiency with oligoclonal T expansion that can be discussed separately.
Patients presenting with CD8 positive T lymphocytosis and often nonspecific clinical symptoms may benefit from combined evaluation of phenotype and clonal expression by the Vβ2 repertoire.
Aim: The aim was to assess the characteristics and outcomes of infections affecting the structures of carious primary molars. Materials and Methods: Forty primary molars were used and classified ...according to the following clinical situation: With profound caries lesion, with bone loss at the furcation region, with perforation of the pulp chamber floor, and residual roots. The teeth were demineralized, cut, and stained with both haematoxylin-eosin and Brown and Brenn staining techniques. Assessment was performed using optical microscopy. Results: Statistical analysis of the data by means of the Chi-square test suggests that there was a significant relationship (P<0.001) between the intensity and localization of infection and the level of destruction of dental structures. A significant difference was also observed in the intensity and localization of infection between the groups regarding crown, furca, and root (P<0.001). Conclusion: More intense and profound the infection, more severe is the dental destruction. The groups of residual roots showed the most severe bacterial infection compared to other groups.
Using a sample of over 400 million φ→KSKL decays produced during the years 2001 and 2002 at the DAΦNE e+e- collider, the ratio RSπ=Γ(KS→π+π-(γ))/Γ(KS→π0π0) has been measured with the KLOE detector. ...The result is RSπ=2.2555±0.0012stat±0.0021corr-stat±0.0050syst, which is in good agreement with the previously published result based on the KLOE data sample from the year 2000. The average of the KLOE results is RSπ=2.2549±0.0054, reducing the total error by a factor of three, to 0.25%.
The LUX-ZEPLIN (LZ) experiment Akimov, D.Yu; Angelides, N.; Araújo, H.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2020, Volume:
953, Issue:
C
Journal Article
Peer reviewed
Open access
We describe the design and assembly of the LUX-ZEPLIN experiment, a direct detection search for cosmic WIMP dark matter particles. The centerpiece of the experiment is a large liquid xenon time ...projection chamber sensitive to low energy nuclear recoils. Rejection of backgrounds is enhanced by a Xe skin veto detector and by a liquid scintillator Outer Detector loaded with gadolinium for efficient neutron capture and tagging. LZ is located in the Davis Cavern at the 4850’ level of the Sanford Underground Research Facility in Lead, South Dakota, USA. We describe the major subsystems of the experiment and its key design features and requirements.
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