1,172 research outputs found
Effectiveness of implant-supported fixed partial denture in patients with history of periodontitis: A systematic review and meta-analysis
Aim: This systematic review investigates the effectiveness of implant-supported fixed partial denture (IS-FPD) in patients with history of periodontitis (HP) vs. patients with no history of periodontitis (NHP). Methods: A literature search was performed on different databases on May 2020. Prospective and retrospective studies assessing survival (primary outcome), success and biological/mechanical complications of IS-FPDs in HP vs. NHP patients at ≥1 year after implant loading were evaluated. Meta-analyses were conducted by estimating hazard ratio (HR), risk ratio (RR) and standardized mean differences (SMD) with 95% confidence intervals (CI) using random effect models. Results: Of the initially identified 4096 articles, 349 underwent a full-text evaluation. Finally, 17 were included. Pooled data analyses showed that overall implant survival was significantly higher in the NHP than the HP group (HR = 2.06; 95% CI = 1.37–3.09; I2 = 0%). This difference was noted when follow-up ≥5 years. The risk of peri-implantitis was higher in HP than NHP patients (RR = 3.3; 95% CI = 1.31–8.3; I2 = 0%), whereas the mean marginal bone level change over time was not different between the groups (SMD = −0.16 mm; 95% CI = −1.04–0.73; I2 = 98%). Conclusions: In partially edentulous patients receiving IS-FPDs, a history of periodontitis is associated with poorer survival rate and higher risk of peri-implantitis during a 5–10 years period after implant loading
Band-theoretical prediction of magnetic anisotropy in uranium monochalcogenides
Magnetic anisotropy of uranium monochalcogenides, US, USe and UTe, is studied
by means of fully-relativistic spin-polarized band structure calculations
within the local spin-density approximation. It is found that the size of the
magnetic anisotropy is fairly large (about 10 meV/unit formula), which is
comparable with experiment. This strong anisotropy is discussed in view of a
pseudo-gap formation, of which crucial ingredients are the exchange splitting
of U 5f states and their hybridization with chalcogen p states (f-p
hybridization). An anomalous trend in the anisotropy is found in the series
(US>>USe<UTe) and interpreted in terms of competition between localization of
the U 5f states and the f-p hybridization. It is the spin-orbit interaction on
the chalcogen p states that plays an essential role in enlarging the strength
of the f-p hybridization in UTe, leading to an anomalous systematic trend in
the magnetic anisotropy.Comment: 4 pages, 5 figure
Magnetic circular dichroism of x-ray absorption spectroscopy at rare-earth L2,3 edges in RE2Fe14B compounds (RE = La, Pr, Nd, Sm, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu)
Magnetic circular dichroism (MCD) in the x-ray absorption spectroscopy (XAS)
at the L2,3 edges for almost entire series of rare-earth (RE) elements in
RE2Fe14B, is studied experimentally and theoretically. By a quantitative
comparison of the complicated MCD spectral shapes, we find that (i) the 4f-5d
intra-atomic exchange interaction not only induces the spin and orbital
polarization of the 5d states, which is vital for the MCD spectra of the
electric dipole transition from the 2p core states to the empty 5d conduction
band, but also it accompanies a contraction of the radial part of the 5d wave
function depending on its spin and orbital state, which results in the
enhancement of the 2p-5d dipole matrix element, (ii) there are cases where the
spin polarization of the 5d states due to the hybridization with the spin
polarized 3d states of surrounding irons plays important roles, and (iii) the
electric quadrupole transition from the 2p core states to the magnetic vale!
nce 4f states is appreciable at the pre-edge region of the dipole spectrum.
Especially, our results evidence that it is important to include the
enhancement effect of the dipole matrix element in the correct interpretation
of the MCD spectra at the RE L2,3 edges.Comment: 9 pages, 5 figures, 1 table, REVTe
Comment on ``Spin Polarization and Magnetic Circular Dichroism in Photoemission from the 2p Core Level of Ferromagnetic Ni''
Although the Ni_4 cluster includes more information regarding the Ni band
structure with respect to the Anderson impurity model, it also favors very
peculiar ground states which are incompatible with a coherent picture of all
dichroism experiments.Comment: 1 page, RevTeX, 1 epsf figur
Specific protein homeostatic functions of small heat-shock proteins increase lifespan
During aging, oxidized, misfolded, and aggregated proteins accumulate in cells, while the capacity to deal with protein damage declines severely. To cope with the toxicity of damaged proteins, cells rely on protein quality control networks, in particular proteins belonging to the family of heat-shock proteins (HSPs). As safeguards of the cellular proteome, HSPs assist in protein folding and prevent accumulation of damaged, misfolded proteins. Here, we compared the capacity of all Drosophila melanogaster small HSP family members for their ability to assist in refolding stress-denatured substrates and/or to prevent aggregation of disease-associated misfolded proteins. We identified CG14207 as a novel and potent small HSP member that exclusively assisted in HSP70-dependent refolding of stress-denatured proteins. Furthermore, we report that HSP67BC, which has no role in protein refolding, was the most effective small HSP preventing toxic protein aggregation in an HSP70-independent manner. Importantly, overexpression of both CG14207 and HSP67BC in Drosophila leads to a mild increase in lifespan, demonstrating that increased levels of functionally diverse small HSPs can promote longevity in vivo
A Systematic Review of Non-pharmacological Strategies to Reduce the Risk of Violence in Patients With Schizophrenia Spectrum Disorders in Forensic Settings
Background: The purpose of this systematic review is to systematically investigate
which non-pharmacological interventions are effective in reducing violence risk among
patients with schizophrenia spectrum disorders (SSD) in forensic settings.
Methods: Six electronic data bases were searched. Two researchers independently
screened 6,003 abstracts resulting in 143 potential papers. These were analyzed in detail
by two independent researchers yielding 10 articles that could be used.
Results: Of the 10 articles, four were non-randomized controlled trials, three were
pre-post studies without controls, and one was observational. Only two studies applied
a randomized controlled trial design. Cognitive behavioral treatment programs were
investigated in three studies. A broad range of other interventions were studied. Often
outcome measures were specific to each study and sample sizes were small. Frequently,
important methodological information was missing from the papers. It was not possible
to carry out a meta-analysis due to the heterogeneity of the study designs and
outcome measures.
Conclusion: Because of methodological limitations it is difficult to draw firm conclusions
about the effectiveness of non-pharmacological interventions to reduce the risk
of violence in patents with SSD in forensic psychiatry settings. Studies applying
better methods in terms of study design, sample sizes and outcome measures are
urgently needed
Rare earth contributions to the X-ray magnetic circular dichroism at the Co K edge in rare earth-cobalt compounds investigated by multiple-scattering calculations
The X-ray magnetic circular dichroism (XMCD) has been measured at the Co K
edge in Co-hcp and R-Co compounds (R=La, Tb, Dy). The structure of the
experimental XMCD spectra in the near-edge region has been observed to be
highly sensitive to the magnetic environment of the absorbing site.
Calculations of the XMCD have been carried out at the Co K edge in Co metal,
LaCo and TbCo within the multiple-scattering framework including the
spin-orbit coupling. In the three systems, the XMCD spectra in the near-edge
region are well reproduced. The possibility to separate and quantitatively
estimate the local effects from those due to the neighboring atoms in the XMCD
cross section makes possible a more physical understanding of the spectra. The
present results emphasize the major role played by the states of the Tb
ions in the XMCD spectrum at the Co K edge in the TbCo compound.Comment: 34 pages, revtex, 10 eps figures included with epsf, after referee
revie
X-Ray Magnetic Circular Dichroism at the K edge of Mn3GaC
We theoretically investigate the origin of the x-ray magnetic circular
dichroism (XMCD) spectra at the K edges of Mn and Ga in the ferromagnetic phase
of Mn3GaC on the basis of an ab initio calculation. Taking account of the
spin-orbit interaction in the LDA scheme, we obtain the XMCD spectra in
excellent agreement with the recent experiment. We have analyzed the origin of
each structure, and thus elucidated the mechanism of inducing the orbital
polarization in the p symmetric states. We also discuss a simple sum rule
connecting the XMCD spectra with the orbital moment in the p symmetric states.Comment: 5 pages, 5 figures, accepted for publication in Physical Review
Design and Vertical Tests of SPS-series Double-Quarter Wave (DQW) Cavity Prototypes for the HL-LHC Crab Cavity System
Crab crossing is essential for high-luminosity colliders. The High Luminosity
Large Hadron Collider (HL-LHC) will equip one of its Interaction Points (IP1)
with Double-Quarter Wave (DQW) crab cavities. A DQW cavity is a new generation
of deflecting RF cavities that stands out for its compactness and broad
frequency separation between fundamental and first high-order modes. The
deflecting kick is provided by its fundamental mode. Each HL-LHC DQW cavity
shall provide a nominal deflecting voltage of 3.4 MV, although up to 5.0 MV may
be required. A Proof-of-Principle (PoP) DQW cavity was limited by quench at 4.6
MV. This paper describes a new, highly optimized cavity, designated DQW
SPS-series, which satisfies dimensional, cryogenic, manufacturing and impedance
requirements for beam tests at SPS and operation in LHC. Two prototypes of this
DQW SPS-series were fabricated by US industry and cold tested after following
conventional SRF surface treatment. Both units outperformed the PoP cavity,
reaching a deflecting voltage of 5.3-5.9 MV. This voltage - the highest reached
by a DQW cavity - is well beyond the nominal voltage of 3.4 MV and may even
operate at the ultimate voltage of 5.0MVwith sufficient margin. This paper
covers fabrication, surface preparation and cryogenic RF test results and
implications
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