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A bstract We study the impact of heavy vector-like leptons on several observables in collider and low-energy physics. These states, present in many well-motivated extensions of the Standard Model, can induce lepton flavour violation and non-standard Higgs decays. We study these effects in a model inspired by the composite Higgs scenario. After deriving bounds on the mass and production cross-section of the vector-like states using recent LHC data on multilepton searches, we discuss the modification of the Higgs decays to dilepton, diphoton and Z γ final states as well as low-energy observables like radiative lepton decays, the anomalous magnetic moment of the muon and the electric dipole moment of the electron. We find several interesting correlations. In particular, we show that branching fractions of lepton flavour-violating Higgs decays at an observable level are prohibited due to the strong bounds on the radiative lepton decays.

Purpose The primary aim of this study was to investigate the potential benefit of stress radiographs for diagnosis of unstable total knee arthroplasty (TKA) and to identify clinically relevant cut-off values to differentiate between unstable and stable TKAs. Methods Data of 40 patients with 49 cruciate retaining (CR) TKA who underwent stress radiographs as part of the diagnostic algorithm in a painful knee clinic were prospectively collected. Anterior and posterior stress radiographs were done in 90° and 15° flexion, varus-valgus stress radiographs in 0° and 30° knee flexion. Knee laxity was measured in mm and degrees by two independent observers using standardized landmarks. Intra- and inter-observer single measure intraclass correlations were between 0.92 to 1 and 0.89 to 1, respectively. For evaluation and investigation of the potential cut-off values, two groups of patients with and without revision surgery due to instability were compared. Radiographic measures of standardized z values according to the group without revision due to instability were used to calculate average and maximum laxity z-scores. Results Knees undergoing revision TKA due to instability showed significantly ( p  < 0.001) lower (KSS) pain/function scores (94 ± 6.3, range 80–100; control group: 112 ± 19.2, range 80–148) and total KSS scores when compared to the control group. The laxity values of patients with instability were significantly higher in terms of mean values ( p  < 0.01) when compared to the control group. The maximum laxity z -score showed the strongest difference between the groups ( R 2  = 0.26, p  < 0.001). The following cut-off values indicating need of revision due to instability were established: in 90° (15°) flexion—anterior translation 5.2 mm (22.4 mm), posterior translation 16.6 mm (13.2 mm); varus stress in 0° (20°–30°) flexion—inlay gap 5.2 mm (6.1 mm) or joint angle 6.1° (6.8°); valgus stress in 0° (20°–30°) flexion—inlay gap 4.6 mm (5.7 mm) or joint angle 5.2° (7.1°). Conclusion Standardized stress radiographs are helpful tools for diagnosis of instability after TKA. The established cut-off values help to guide decision making in this challenging group of patients. However, laxity values should not be considered as the only criteria for diagnosis of unstable TKA. Level of evidence IV.

The resistance to oxidizing environments exhibited by some Mn+1AXn (MAX) phases stems from the formation of stable and protective oxide layers at high operating temperatures. The MAX phases are hexagonally arranged layered nitrides or carbides with general formula Mn+1AXn, n = 1, 2, 3, where M is early transition elements, A is A block elements, and X is C/N. Previous attempts to model and assess oxide phase stability in these systems has been limited in scope due to higher computational costs. To address the issue, we developed a machine-learning driven high-throughput framework for the fast assessment of phase stability and oxygen reactivity of 211 chemistry MAX phase M2AX. The proposed scheme combines a sure independence screening sparsifying operator-based machine-learning model in combination with grand-canonical linear programming to assess temperature-dependent Gibbs free energies, reaction products, and elemental chemical activity during the oxidation of MAX phases. The thermodynamic stability, and chemical activity of constituent elements of Ti2AlC with respect to oxygen were fully assessed to understand the high-temperature oxidation behavior. The predictions are in good agreement with oxidation experiments performed on Ti2AlC. We were also able to explain the metastability of Ti2SiC, which could not be synthesized experimentally due to higher stability of competing phases. For generality of the proposed approach, we discuss the oxidation mechanism of Cr2AlC. The insights of oxidation behavior will enable more efficient design and accelerated discovery of MAX phases with maintained performance in oxidizing environments at high temperatures.

BACKGROUND: The purpose of the study was to analyse mandibular anterior teeth in a Polish population and determine the symmetry of root and root canal morphology between the right and left side using cone-beam computed tomography (CBCT) scanning. MATERIALS AND METHODS: From 111 CBCT examinations, 303 pairs of equivalent mandibular anterior teeth were analysed on the right and left sides to evaluate symmetry. Axial, sagittal, and cross-sectional slices with a thickness of 0.2–0.25 mm were used. The number of root canals and their internal patterns were classified following Vertucci’s criteria. RESULTS: All incisors in this study had 1 root. Canines usually had a single root and much less often had 2 roots. Type I and III root canal configurations were found most often, while type V and II configurations were less frequent. Significant compatibility between the left and right side was observed in all evaluated variables. Incisors had the highest symmetry with regard to the number of roots (100%). Second canals were observed more often in males than females, but only the results in lateral incisors were significant. CONCLUSIONS: This study provides supplemental information for dentists and should help them to better predict the morphology of mandibular anterior teeth in complicated cases in the Polish population. Symmetry was observed in roots and root canal morphology in all examined parameters.

A bstract In the absence of a Higgs boson, the perturbative description of the Standard Model ceases to make sense above a TeV. Heavy spin-1 fields coupled to W and Z bosons can extend the validity of the theory up to higher scales. We carefully identify regions of parameter space where a minimal addition — a single spin-1 SU(2) custodial -triplet resonance — allows one to retain perturbative control in all channels. Elastic scattering of longitudinal W and Z bosons alone seems to permit a very large cut-off beyond the Naive Dimensional Analysis expectation. We find however that including scattering of the spin-1 resonances then leads to an earlier onset of strong coupling. Most importantly for LHC searches, we define a self-consistent set-up with a well-defined range of validity without recourse to unitarization schemes whose physical meaning is obscure. We discuss the LHC phenomenology and the discovery reach for these electroweak resonances and mention the possibility of a nightmare scenario with no Higgs nor resonance within the LHC reach. Finally, we discuss the effects of parity breaking in the heavy resonance sector which reduces the contributions to the S parameter.

A bstract We discuss how to perform consistent extractions of anomalous triple gauge couplings (aTGC) from electroweak boson pair production at the LHC in the Standard Model Effective Field Theory (SMEFT). After recasting recent ATLAS and CMS searches in pp → W Z ( W W ) → ℓ′νℓ + ℓ − (ν ℓ ) channels, we find that: (a) working consistently at order Λ −2 in the SMEFT expansion the existing aTGC bounds from Higgs and LEP-2 data are not improved, (b) the strong limits quoted by the experimental collaborations are due to the partial Λ −4 corrections (dimension-6 squared contributions). Using helicity selection rule arguments we are able to explain the suppression in some of the interference terms, and discuss conditions on New Physics (NP) models that can benefit from such LHC analyses. Furthermore, standard analyses assume implicitly a quite large NP scale, an assumption that can be relaxed by imposing cuts on the underlying scale of the process ( s ^ ). In practice, we find almost no correlation between s ^ and the experimentally accessible quantities, which complicates the SMEFT interpretation. Nevertheless, we provide a method to set (conservative) aTGC bounds in this situation, and recast the present searches accordingly. Finally, we introduce a simple NP model for aTGC to compare the bounds obtained directly in the model with those from the SMEFT analysis.

Objective To characterize quadriceps femoris tendon tears on magnetic resonance (MR) imaging regarding tear extent, location, and presence of bony avulsion. Materials and methods IRB approval was obtained and informed consent was waived for this retrospective case series. Electronic medical records from all patients in our hospital system were searched for keywords: knee MR imaging, and quadriceps tendon rupture or tear. MRI studies were randomized and independently evaluated by two fellowship-trained musculoskeletal radiologists. MR imaging was used to characterize each individual quadriceps tendon as having tendinosis, tear (location, partial versus complete, size, and retraction distance), and bony avulsion. Knee radiographs were reviewed for presence or absence of bony avulsion. Descriptive statistics and inter-reader reliability (Cohen’s Kappa and Wilcoxon-signed-rank test) were calculated. Results Fifty-two patients with 53 quadriceps tears were evaluated (45 males, 7 females; mean age: 51 ± 13 years). The vastus intermedius (VI) tendon more often incurred a partial rather than a complete tear (39.6% vs. 37.7%), while the rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) incurred complete tears more commonly (64.2–66%). Subjects with bony avulsion on radiographs had higher-grade tears of the RF, VM, and VL tears ( p = 0.020–0.043) but not the VI. Most tendons tore at or immediately proximal to the patella (84.8–93.6%). Gaps in retracted torn tendons measured between 2.3 and 2.7 cm. Inter-reader reliability was substantial to almost perfect (κ = 0.624–0.953). Conclusion Quadriceps femoris tendon tears most commonly involve the RF or VL/VM layers usually in proximity to the patella. A bony avulsion correlates with a more extensive tear. Key Points • Quadriceps femoris tendon tears most commonly involve the rectus femoris or vastus lateralis/vastus medialis layers. • A rupture of the quadriceps femoris tendon usually occurs in proximity to the patella. • A bony avulsion of the patella correlates with a more extensive tear of the superficial and middle layers of the quadriceps tendon.

A comparison was made of sirolimus–eluting stents and bare stents as an effective means of treatment of stenosis in crural arteries. Patients were randomly divided into two groups: (1) patients treated with sirolimus-eluting stents and (2) patients treated with bare stents. Each group consisted of 25 patients, and every patient had one stent implanted. All patients showed symptoms of ischemia of the peripheral arteries, classified according to the Rutherford scale into categories 3, 4, and 5. All patients were examined 24 h before and 24 h and 6 months after the intervention. The results were analyzed according to clinical, hemodynamic, and angiographic criteria. Technically, the procedure was successful in 100% of cases, and both groups presented an equal improvement in clinical and hemodynamic parameters. The follow-up angiographic examination demonstrated a significantly lower rate of restenosis among the sirolimus-eluting stent group (4, 16%) versus the bare stent group (19, 76%) (p < 0.001), with lower target lesion revascularization in 3 (12%) versus 14 (56%) (p < 0.05), respectively. Quantitative angiography demonstrated that all variables used to assess restenosis were superior for sirolimus-eluting stents 6 months after intervention: late lumen loss 0.46 ± 0.72 versus 1.70 ± 0.94 (p < 0.001) and minimal lumen diameter 2.25 ± 0.82 versus 0.99 ± 1.08 (p < 0.001). Results of this study reveal that the use of sirolimus-eluting stents decreases the risk of restenosis in comparison to standard stents.

Purpose To evaluate the treatments of a short-segment atherosclerotic stenosis in the superficial femoral arteries with the cutting balloon angioplasty (CBA) versus conventional balloon angioplasty [percutaneous transluminal angioplasty (PTA)] in a randomized controlled trial. Material and Methods The study group comprised 60 patients (33 men, 27 women; average age 64 years) with a short (≤5 cm) focal SFA de novo atherosclerotic stenosis associated with a history of intermittent claudication or rest pain. The primary end point of this study was the rate of binary restenosis in the treated segment 12 months after the intervention. All patients were evenly randomized to either the PTA or CBA treatment arms. Follow-up angiograms and ankle–brachial index (ABI) measurements were performed after 12 months. The evaluation of the restenosis rates and factors influencing its occurrence were calculated by logistic regression analysis. Results In the intention-to-treat analysis, restenosis rates after 2-month follow-up were 9 of 30 (30 %) in the PTA group and 4 of 30 (13 %) in the CBA group ( p  = 0.117). In the actual treatment analysis, after exclusion of patients who required nitinol stent placement for a suboptimal result after angioplasty alone (5 patients in the PTA group and none in the CBA group), restenosis rates were 9 of 25 (36 %) and 4 of 30 (13 %), respectively ( p  = 0.049). In the intention-to-treat analysis there were also significant differences in ABI values between the PTA and CBA groups at 0.77 ± 0.11 versus 0.82 ± 0.12, respectively ( p  = 0.039), at 12 months. Conclusion Based on the presented results of the trial, CBA seems to be a safer and more effective than PTA for treatment of short atherosclerotic lesions in the superior femoral artery.