Does Previous Hip Surgery Effect the Outcome of Tönnis Triple Periacetabular Osteotomy? Mid-Term Results

Hip dysplasia (HD) is 1 of the major reasons of coxarthrosis. The goal of the treatment of HD by Tönnis triple pelvic osteotomy (TPAO) is to improve the function of hip joint while relieving pain, delaying and possibly preventing end-stage arthritis. The aim of this study is to compare the clinical and radiological results of TPAO to determine if previous surgery has a negative effect on TPAO. Patients operated with TPAO between 2005 and 2010, included in this study. Patients divided into 2 groups: primary acetabular dysplasia (PAD) and residual acetabular dysplasia (RAD). Prepostoperatively, hip range of motion, Harris hip score (HHS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) hip score, visual analog scores (VAS), impingement tests, and also the presence of Trendelenburg sign (TS) were investigated for clinical evaluation. For radiological analysis pre–postoperative, anterior–posterior (AP) pelvis and faux profile radiographs were used. Acetabular index, lateral center edge (LCE) angle, and Sharp angles were measured by AP pelvis; anterior center edge (ACE) angle were measured by faux profile radiography. All the clinical and radiological data of the groups were analyzed separately for the pre–postoperative scores also the amount of improvement in all parameters were analyzed. SPSS20 (SPSS Inc., Chicago, IL) was used for statistical analysis. Wilcoxon test, McNemar test, paired t tests, and Mann–Whitney U tests were used to compare the groups. P  < 0.05 were defined as statistically significant. Study included 27 patients: 17 patients were in PAD and 10 patients were in RAD. The mean follow-up period was 6.2 years (5.2–10.3 years). In all patients, the radiological and the clinical outcomes were better after TPAO except the flexion of the hip parameter. When the patient groups were evaluated as pre–postoperatively, more statistically significant parameters were found in the PAD group when compared with RAD group. Extension, impingement, TS, VAS, HHS, WOMAC score parameters in clinical outcome and LCE, ACE, Sharp angle, coverage ratio in radiological results were significantly better in PAD group postoperatively but in RAD group; only extension, VAS, HHS, and WOMAC parameters were clinically and LCE and Coverage ratio were significantly different compared with the preoperative measurements. The change of the parameters that used for the evaluation of clinical and radiological results did not show a significant difference between groups. Our data suggest that TPAO can be performed on patients with HD for both groups. Although there were fewer parameters which changed significantly after TPAO in RAD patients; the improvement of radiological and clinical results was similar for groups. Further long-term follow-up studies with large number of patients are needed to determine the proper results of TPAO.

Non-dimensional physics of pulsatile cardiovascular networks and energy efficiency

In Nature, there exist a variety of cardiovascular circulation networks in which the energetic ventricular load has both steady and pulsatile components. Steady load is related to the mean cardiac output (CO) and the haemodynamic resistance of the peripheral vascular system. On the other hand, the pulsatile load is determined by the simultaneous pressure and flow waveforms at the ventricular outlet, which in turn are governed through arterial wave dynamics (transmission) and pulse decay characteristics (windkessel effect). Both the steady and pulsatile contributions of the haemodynamic power load are critical for characterizing/comparing disease states and for predicting the performance of cardiovascular devices. However, haemodynamic performance parameters vary significantly from subject to subject because of body size, heart rate and subject-specific CO. Therefore, a 'normalized' energy dissipation index, as a function of the 'non-dimensional' physical parameters that govern the circulation networks, is needed for comparative/integrative biological studies and clinical decision-making. In this paper, a complete network-independent non-dimensional formulation that incorporates pulsatile flow regimes is developed. Mechanical design variables of cardiovascular flow systems are identified and the Buckingham Pi theorem is formally applied to obtain the corresponding non-dimensional scaling parameter sets. Two scaling approaches are considered to address both the lumped parameter networks and the distributed circulation components. The validity of these non-dimensional number sets is tested extensively through the existing empirical allometric scaling laws of circulation systems. Additional validation studies are performed using a parametric numerical arterial model that represents the transmission and windkessel characteristics, which are adjusted to represent different body sizes and non-dimensional haemodynamic states. Simulations demonstrate that the proposed non-dimensional indices are independent of body size for healthy conditions, but are sensitive to deviations caused by off-design disease states that alter the energetic load. Sensitivity simulations are used to identify the relationship between pulsatile power loss and non-dimensional characteristics, and optimal operational states are computed

Single Cell Expression Data Reveal Human Genes that Escape X-Chromosome Inactivation

Quantum Emission from Defects in Single-Crystalline Hexagonal Boron Nitride

Bulk hexagonal boron nitride (hBN) is a highly nonlinear natural hyperbolic material that attracts major attention in modern nanophotonics applications. However, studies of its optical properties in the visible part of the spectrum and quantum emitters hosted by bulk hBN have not been reported to date. In this work, we study the emission properties of hBN crystals in the red spectral range using sub-band-gap optical excitation. Quantum emission from defects is observed at room temperature and characterized in detail. Our results advance the use of hBN in quantum nanophotonics technologies and enhance our fundamental understanding of its optical properties

Ultrafast Spin-Transfer-Torque Switching of Synthetic Ferrimagnets

The state-of-the-art switching speeds of spin-transfer-torque-driven free layers in magnetic tunnel junctions (MTJs) are of the order of a few hundred picoseconds, hindering their wide implementation in memory and logic devices. To significantly speed up the spin-torque-driven reversal time, we propose a composite free-layer structure using synthetic ferrimagnets (SFMs). It is commonly assumed that to achieve a given switching delay, the current must exceed the critical current by a certain factor; therefore a higher critical current implies a higher switching current. We show that this is not the case for SFM structures, and that they can provide significantly reduced switching delays for a given current density even though the critical current is increased. This non-intuitive result can be understood from the requirements of angular momentum conservation. We predict that a 20 nm diameter MTJ incorporating the proposed SFM free layer can be switched in tens of picoseconds, which could advance the state-of-the-art of sub-200 ps switching. We show that this speed can be achieved by experimentally demonstrated parameters using current perpendicular magnetic anisotropy materials.

Rare and Severe Maxillofacial Injury Due to Tear Gas Capsules: Report of Three Cases

Tear gases are used by police or armed forces for control of riots or social events or by the general population for private self‐defense. These agents are used widely throughout the world, but some harmful effects have reported. In addition, despite well‐defined chemical side effects documented in the literature, data are insufficient regarding mechanical injury due to tear gas capsules. We report three cases of severe maxillofacial injury in patients who had these capsules fired from tear gas guns directly to their faces. The capsules penetrated the patients' faces, causing potentially fatal injuries. To our knowledge, reports of this kind of injury related to tear gas capsules are very rare in the literature. In conclusion, tear gas guns may be very dangerous in terms of human health and they may cause severe injuries, especially when they are not used according to strict guidelines.

The Front End of Radical Innovation: A Case Study of Idea and Concept Development at Prime Group

A firm's ability to develop radical innovation is heavily contingent on the front‐end phases where ideas and concepts are created, yet few empirical studies provide detailed insights into radical idea and concept development. Using literature on problem finding and problem solving, we explore how radically new ideas and concepts emerge, and outline the process by which they are created. Based on multiple case studies of five completed and two ongoing projects conducted by a highly innovative consultancy firm, Prime Group, the article proposes a six‐step process for radical idea and concept development. The insights provide theoretical implications and advice for how firms can increase novelty and success rates of emergent radical ideas and concepts.

Contact allergens in ‘natural’ hair dyes

Studies have shown that conventional oxidative (often called permanent) hair dye products contain numerous potent sensitizing hair dye substances (1–4), but little is known regarding the growing market of so-called organic or ‘natural’ alternatives. Our aim was to investigate the occurrence of contact allergens in hair dye products advertised as ‘organic’, ‘natural’, or similar, or used in hairdressing salons branded with such attributes.

Comparative sensitizing potencies of fragrances, preservatives, and hair dyes

Summary The local lymph node assay (LLNA) is used for assessing sensitizing potential in hazard identification and risk assessment for regulatory purposes. Sensitizing potency on the basis of the LLNA is categorized into extreme (EC3 value of ≤0.2%), strong (>0.2% to ≤2%), and moderate (>2%). To compare the sensitizing potencies of fragrance substances, preservatives, and hair dye substances, which are skin sensitizers that frequently come into contact with the skin of consumers and workers, LLNA results and EC3 values for 72 fragrance substances, 25 preservatives and 107 hair dye substances were obtained from two published compilations of LLNA data and opinions by the Scientific Committee on Consumer Safety and its predecessors. The median EC3 values of fragrances (n = 61), preservatives (n = 19) and hair dyes (n = 59) were 5.9%, 0.9%, and 1.3%, respectively. The majority of sensitizing preservatives and hair dyes are thus strong or extreme sensitizers (EC3 value of ≤2%), and fragrances are mostly moderate sensitizers. Although fragrances are typically moderate sensitizers, they are among the most frequent causes of contact allergy. This indicates that factors other than potency need to be addressed more rigorously in risk assessment and risk management.

Frequency of body dysmorphic disorder among patients with complaints of hair loss

Background Body dysmorphic disorder ( BDD ) is a psychiatric condition in which a disabling preoccupation with a non‐existent or slight defect in appearance is the main symptom. Hair concerns are frequent in patients with BDD . Objectives The purpose of this study was to determine the prevalence of BDD among patients with complaints of hair loss. Methods A validated BDD questionnaire ( BDDQ ) was administered to 150 patients with complaints of hair loss and 150 control subjects who were selected from among general dermatology ( GD ) patients. Standard statistical tests were performed (descriptive analysis, chi‐squared tests, non‐parametric tests). Differences that achieved a P ‐value of <0.05 were considered statistically significant. Results Among patients with complaints of hair loss, 42 of 142 subjects retained in the study (29.6%; 31 females and 11 males) were diagnosed with BDD . Furthermore, 25.6% of female patients and 52.4% of male patients were diagnosed with BDD ( P  = 0.013). Hair concerns were more common in males than in females ( P  < 0.05). In the GD group, four control subjects (2.7%, all female) were diagnosed with BDD ; all of their concerns focused on the body and acne. Conclusions The incidence of BDD is about 10 times higher in patients with complaints of hair loss than it is in GD patients and is higher in males. Awareness of the condition and the referral of selected patients to mental health professionals is crucial.