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The strongly correlated material FeSi exhibits several unusual thermal, magnetic, and structural properties under varying pressure-temperature (P-T) conditions. It is a potential thermoelectric alloy and a materials of several geological implications as a possible constituent at the Earth's core mantle boundary (CMB). The phase transition behavior and lattice dynamics of FeSi under different P-T conditions remain elusive. A previous theoretical work predicted a pressure induced B20-B2 transition at ambient temperature, yet the transition is only observed at high P-T conditions in the experiments. Furthermore, the closing of the electronic gap due to a dramatic renormalization of the electronic structure and phonon anomalies has been reported based on density function calculations. In this study we have performed high pressure powder diffraction and Nuclear Resonant Inelastic X-ray Scattering (NRIXS) measurements up to 120 GPa to understand the phase stability and the lattice dynamics. Our study shows evidence for a nonhydrostatic stress induced B20-B2 transition in FeSi around 36 GPa for the first time. The Fe partial phonon density of states (PDOS) and thermal parameters were derived from NRIXS up to 120 GPa with the density function theoretical (DFT) calculations. These calculations further predict and are consistent with pressure-induced metallization and band gap closing around 12 GPa., Comment: 8 pages, 6 figures and supplementary information

Background Vasospasm is a major problem following microsurgical reconstruction which can result in the partial or complete loss of the flap tissue. The aim of this study was to investigate the efficiency of hydrodilatation for the prevention of vasospasm. Methods Thirty male Wistar rats were used for this experimental study. Femoral arteries of were exposed, photographed, and transected. In group 1, group 2, and group 3 papaverine solution, hydrodilatation, and minimal mechanical dilatation (control group) was performed, respectively. The anastomosis was completed and the arteries were photographed again 10 minutes after completion of the anastomosis. Following 7-day period samples for transmission electron microscopy (TEM) and light microscopy were obtained. Results The mean vessel diameters prior to transection were 0.43, 0.45, and 0.52 mm in the papaverine, hydrodilatation, and control groups, respectively. The mean vessel diameter 10 minutes following the completion of anastomosis was 0.76, 0.75, and 0.51 mm in the papaverine, hydrodilatation, and control groups, respectively. Median score for papaverine group regarding histological parameters of regular endothelial lining and lumen, neutrophil infiltration, vascular congestion, and edema in tunica adventitia was 2, 3, 2, and 3 positive, respectively. Median score for the papaverine group regarding histological parameters of regular endothelial lining and lumen, neutrophil infiltration, vascular congestion, and edema in tunica adventitia was 3, 3, 3, and 3 positive, respectively. All the histological scores were negative in the control group. The difference between the control group and the experiment groups 1 and 2 was significant regarding all four histological parameters (p Conclusion Hydrodilatation and papaverine application were both effective in preventing vasospasm following microsurgical intervention but papaverine caused slightly less damage to the endothelial lining and less edema in the tunica adventitia when compared with the hydrodilatation. Hydrodilatation group showed a vasodilatory effect that was statistically similar to that of papaverine, which has a proven efficacy.

Nasal reconstruction is one of the most challenging procedures in plastic surgery. To get optimal aesthetic and functional results, the surgeon should know all the options well. Forehead flap is the gold standard technique for closure of medium to large defects of the nose. Although it provides a very good color and texture match, it may become a difficult option in patients with poor condition. The aim of this study was to define a simpler technique for nasal reconstruction using combined local flaps.Twelve patients, operated using a dorsal nasal flap combined with a nasolabial perforator propeller flap, were presented in the study. Properties of the patients, defect size and locations, and complications were evaluated.The mean size of the reconstructed defects was 10.1 cm2. No flap loss was observed. Venous congestion was the most common complication and resolved spontaneously in all cases. Two cases had partial distal necrosis, which also healed spontaneously.Closure was achieved successfully in all cases with a medium to large nasal defect using a combined dorsal nasal flap and nasolabial perforator propeller flap. This method can be used as an alternative to forehead flap.

Background Nasolabial flap is a work-horse flap for coverage of many facial units. However, these flaps have limited mobility and these limit their use in many instances. Facial artery with its numerous small cutaneous perforators can be a source for free-style skin flaps that can be islanded and have greater reach, one of which is nasolabial perforatory flap. Methods The authors present a case series of 35 patients with central facial unit defects reconstructed by a single flap harvested from the nasolabial sulcus. Results In our series, we did not encounter any significant flap loss and patient satisfaction was high both functionally and aesthetically. Main drawbacks were temporary venous congestion and hair bearing flaps in male patients. Conclusion The authors think with its reliability and versatility nasolabial perforator flaps, based on the same donor area as the traditional nasolabial flap can be a valuable addition to our arsenal in reconstruction of central facial unit defects.

Radiation-induced wounds are extremely difficult to treat. They may lead to severe infections and can even be life-threatening. Wound dressings, negative pressure wound treatment, hyperbaric oxygen therapy, and antibiotics are the main treatment modalities for radiation-induced wounds. Amniotic membrane is the innermost surface of the placenta. It has been shown that amniotic membrane induces re-epithelization, regulates angiogenesis, and decreases inflammation and fibrosis. Our proposed theory was that amniotic membrane can have a role in treating radiation-induced wounds by inducing epithelization and increasing wound tensile strength. Out of 24 rats, 3 groups were composed. In group A, 21 days after one session of radiotherapy, a 2-cm incision was made on the gluteal region then an amniotic membrane was placed under the skin flaps. In group B, 21 days after one session of radiotherapy, a 2-cm incision made on the gluteal region and wound is sutured back after 2 × 2 cm of area was undermined. In group C, no radiotherapy is given. We just made an incision and sutured it back again with the same size of area undermined. Three weeks after these surgeries, wound regions were excised en bloc and taken out for biomechanical and histopathological assessments. The end results in amniotic membrane group (group A) were statistically higher than those in the other groups in the terms of wound healing and biomechanical measurements. After biomechanical and histopathological evaluation, amniotic membrane, with its antimicrobial, anti-inflammatory, angiogenic, and epithelial-inductive effects, was found to be affective in post-radiation wound treatment. Due to the features of amniotic membrane mentioned above, it can be an option in treatment of patients which received neoadjuvant radiotherapy to prevent future wounds. It can also be used for the care and treatment of post-radiation wounds. Level of Evidence: Not ratable

Whereas body-contouring surgery after massive weight loss in women receives much attention, little attention has been devoted to accentuating the male physique. Male patients after massive weight loss often suffer from redundant skin and soft tissue in the anterior and lateral chest region, causing various deformities of pseudogynecomastia. The authors present their approach to high-grade pseudogynecomastia correction with preservation of the NAC on an inferior dermoglandular pedicle with transverse scar only closure and without any meaningful liposuction. A description of comprehensive pseudogynecomastia correction with the aforementioned technique followed by review of 58 consecutive patients operated on in our clinic from January 2017 to June 2018. Epidemiological data such as age, weight, height, body mass index (BMI), weight loss, and the medical history of each patient were collected. All patients were photo-documented preoperatively and postoperatively in a standard manner. During the operation, weight of resected tissue and operative time were noted. Fifty-eight patients were operated on in a single stage. In our series, one patient had unilateral partial necrosis on nipple–areola complex, and two patients had minimal to moderate amounts of hematoma which were followed up without intervention. We did not encounter any infection-related complications or skin redundancy in our patients. Out of 58 patients, 55 of all the patients were highly satisfied with the aesthetic results. Three patients were mildly satisfied with the results, but they stress that moderate scar widening was the reason for the displeasure, not the definition of the chest which was deemed as satisfactory like the rest. Our technique obviates the need for skin resection in a second operation, allows immediate skin recontouring, and provides a viable nipple–areola complex at the desired location. The patient does not have to suffer prolonged stress while awaiting skin retraction and is protected from a second dose of anesthesia and hospitalization. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A fat graft is the closest thing to being the ideal soft tissue filler. Although it has many advantages, reliability of late-term survival is a never-ending debate. Although there are observational studies that research the effect of cigarette smoke on fat graft take in clinical setting, there has not been an objective experimental animal study on the affect of smoking on fat graft survival. The aim of our study is to search if smoking has an affect on fat grafts. Twenty-two Sprague-Dawley type rats were used. Exposure was maintained via a passive smoke exposure system. Rats were divided into three groups regarding their exposure period. At the end of the study, transferred fat grafts were extracted and weighed with a precision scale, an arterial blood sample was taken for biochemical analysis, and grafts were sent to the pathology laboratory for immunohistochemical assessment. There were meaningful differences between the control group and the other two groups in graft weight loss, serum cotinine, tissue MDA, adipose tissue/fibrosis ratio, stem cell counts, perilipin positive cell density and inflammation density. Furthermore, we detected meaningful correlations between serum cotinine, tissue MDA and graft weight loss. Fat graft takes with the same mechanisms as a wound heals. So like wound healing, cigarette smoke has a negative affect on fat graft survival. A fat graft is by its nature an elective procedure so to improve our late-term success, cigarette smoke exposure should be kept to a minimum for increased reliability. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .