Robust Bain distortion in the premartensite phase of platinum substituted Ni2MnGa magnetic shape memory alloy

The premartensite phase of shape memory and magnetic shape memory alloys (MSMAs) is believed to be a precursor state of the martensite phase with preserved austenite phase symmetry. The thermodynamic stability of the premartensite phase and its relation to the martensitic phase is still an unresolved issue, even though it is critical to the understanding of the functional properties of MSMAs. We present here unambiguous evidence for macroscopic symmetry breaking leading to robust Bain distortion in the premartensite phase of 10% Pt substituted Ni2MnGa. We show that the robust Bain distorted premartensite (T2) phase results from another premartensite (T1) phase with preserved cubic-like symmetry through an isostructural phase transition. The T2 phase finally transforms to the martensite phase with additional Bain distortion on further cooling. Our results demonstrate that the premartensite phase should not be considered as a precursor state with the preserved symmetry of the cubic austenite phase

Direct measurements of the magnetocaloric effect in pulsed magnetic fields: The example of the Heusler alloy Ni50_{50}Mn35_{35}In15_{15}

We have studied the magnetocaloric effect (MCE) in the shape-memory Heusler alloy Ni$_{50}$Mn$_{35}$In$_{15}$ by direct measurements in pulsed magnetic fields up to 6 and 20 T. The results in 6 T are compared with data obtained from heat-capacity experiments. We find a saturation of the inverse MCE, related to the first-order martensitic transition, with a maximum adiabatic temperature change of $\Delta T_{ad} = -7$ K at 250 K and a conventional field-dependent MCE near the second-order ferromagnetic transition in the austenitic phase. The pulsed magnetic field data allow for an analysis of the temperature response of the sample to the magnetic field on a time scale of $\sim 10$ to 100 ms which is on the order of typical operation frequencies (10 to 100 Hz) of magnetocaloric cooling devices. Our results disclose that in shape-memory alloys the different contributions to the MCE and hysteresis effects around the martensitic transition have to be carefully considered for future cooling applications.Comment: 5 pages, 4 figure

A Systematic Literature Review: Workplace Violence Against Emergency Medical Services Personnel

Context: In spite of the high prevalence and consequences of much workplace violence against emergency medical services personnel, this phenomenon has been given insufficient attention. A systematic review can aid the development of guidelines to reduce violence. Objectives: The research question addressed by this paper is, “What are the characteristics and findings of studies on workplace violence against emergency medical services personnel”? Data Sources: A systematic literature review was conducted using online databases (PubMed, Scopus, Google Scholar, and Magiran) with the help of experienced librarians. Study Selection: Inclusion criteria comprised studies in the English or Persian language and researcher’s access to the full text. There was no limit to the entry of the study design. Exclusion criteria included lack of access to the full text of the article, studies published in unreliable journals or conferences, and studies in which the results were shared with other medical or relief groups and there was no possibility of breaking down the results. Data Extraction: A “Data extraction form” was designed by the researchers based on the goals of the study that included the title and author(s), study method (type, place of study, sample size, sampling method, and data collection/analysis tool), printing location, information related to the frequency of types of violence, characteristics of victims /perpetrators, and related factors. Results: The papers reviewed utilized a variety of locations and environments, methods, and instrument samplings. The majority of the studies were performed using the quantitative method. No intervention study was found. Most studies focused on the prevalence of violence, and their results indicated that exposure to violence was high. The results are presented in six major themes. Conclusions: Workplace violence and injuries incurred from it are extensive throughout the world. The important causes of violence include the shortage of training programs dealing with violence, lack of violence management protocols, and delays in response times. Therefore, afterthought and resolve are more crucial than ever. Workplace violence reduction strategies and suggestions for future studies are also discussed

Leiomyosarcoma of inferior vena cava and right atrium with Ascites and Jaundice: A case report

Leiomyosarcoma is one of the soft tissue sarcomas that could originate from different parts of body and are mostly presented as retropritoneal mass. Leiomyosarcomas of vascular origin are particularly rare tumors occurring mainly in inferior vena cava (IVC). Here, we report the case of a 35-year-old male patient who presented with ascites and jaundice. Further evaluation revealed large hepatic and cardiac masses with extension to IVC. Since it was not possible to determine the point of origin of leiomyosarcoma, the patient received chemotherapy under diagnosis of metastatic leiomyosarcoma but unfortunately passed away. © 2016, Tehran University of Medical Sciences (TUMS). All rights reserved

The requirements and challenges in preventing of road traffic injury in Iran. A qualitative study

<p>Abstract</p> <p>Background</p> <p>Road traffic injuries (RTIs) are a major public health problem, especially in low- and middle-income countries. Among middle-income countries, Iran has one of the highest mortality rates from RTIs. Action is critical to combat this major public health problem. Stakeholders involved in RTI control are of key importance and their perceptions of barriers and facilitators are a vital source of knowledge. The aim of this study was to explore barriers to the prevention of RTIs and provide appropriate suggestions for prevention, based on the perceptions of stakeholders, victims and road-users as regards RTIs.</p> <p>Methods</p> <p>Thirty-eight semi-structured interviews were conducted with informants in the field of RTI prevention including: police officers; public health professionals; experts from the road administrators; representatives from the General Governor, the car industry, firefighters; experts from Emergency Medical Service and the Red Crescent; and some motorcyclists and car drivers as well as victims of RTIs. A qualitative approach using grounded theory method was employed to analyze the material gathered.</p> <p>Results</p> <p>The core variable was identified as "The lack of a system approach to road-user safety". The following barriers in relation to RTI prevention were identified as: human factors; transportation system; and organizational coordination. Suggestions for improvement included education (for the general public and targeted group training), more effective legislation, more rigorous law enforcement, improved engineering in road infrastructure, and an integrated organization to supervise and coordinate preventive activities.</p> <p>Conclusion</p> <p>The major barriers identified in this study were human factors and efforts to change human behaviour were suggested by means of public education campaigns and stricter law enforcement. However, the lack of a system approach to RTI prevention was also an important concern. There is an urgent need for both an integrated system to coordinate RTI activities and prevention and a major change in stakeholders' attitudes towards RTI prevention. The focus of all activities should take place on road users' safety.</p

Treatment of third-degree burn wounds in animal specimens: Acellular dermis or partial-thickness skin graft Traitement des brûlures du 3ème degré chez l�animal: Derme acel-lulaire ou greffe semi-épaisse

Several dermal products have been introduced to substitute dermal tissues. In this study we review the effects of these products on repairing third-degree burn wounds and managing complications in animal specimens. Using an interventional approach, rats were randomly assigned to four groups (G1 to G4). Two wounds were created on the back of each rat. An open wound was left on the back of rats in G1; in G2, wounds were covered with a thick rat derived-ADM product and overlying thin skin graft; on G3 rats, similar third degree ulcers were made with one ulcer covered with harvested thin skin graft. In G4, ulcers were covered with a thin rat derived-ADM product and thin graft. Factors such as take rate, histopathological score, wound contracture and graft contracture were compared on the 7th, 15th, 21st and 30th day. Mean graft take rate on the 30th day in the thick ADM, thin ADM and graft group showed a significant difference (p=0.015). Histopathological score on the 30th day in the thin ADM, thick ADM and graft group showed no considerable difference. Mean graft take rate was significantly better in the thin ADM and graft group than in the thick ADM group. Wound contracture was significantly more severe in the thick ADM and control group than in the thin ADM and graft group. © 2018, Mediterranean Club for Burns and Fire Disasters. All rights reserved

Pressure tuning of the anomalous Hall effect in the chiral antiferromagnet Mn3Ge

We report on the pressure evolution of the giant anomalous Hall effect (AHE) in the chiral antiferromagnet Mn$_3$Ge. The AHE originating from the non-vanishing Berry curvature in Mn$_3$Ge can be continuously tuned by application of hydrostatic pressure. At room temperature, the Hall signal changes sign as a function of pressure and vanishes completely at $p=1.53$ GPa. Even though the Hall conductivity changes sign upon increasing pressure, the room-temperature saturation value of 23 ${\rm \Omega^{-1}cm^{-1}}$ at 2.85 GPa is remarkably high and comparable to the saturation value at ambient pressure of about 40 ${\rm \Omega^{-1}cm^{-1}}$. The change in the Hall conductivity can be directly linked to a gradual change of the size of the in-plane components of the Mn moments in the non-collinear triangular magnetic structure. Our findings, therefore, provide a route for tuning of the AHE in the chiral antiferromagnetic Mn$_3$Ge.Comment: 5 pages, 4 figure

Large-scale magnetic fields from inflation due to a CPTCPT-even Chern-Simons-like term with Kalb-Ramond and scalar fields

We investigate the generation of large-scale magnetic fields due to the breaking of the conformal invariance in the electromagnetic field through the $CPT$-even dimension-six Chern-Simons-like effective interaction with a fermion current by taking account of the dynamical Kalb-Ramond and scalar fields in inflationary cosmology. It is explicitly demonstrated that the magnetic fields on 1Mpc scale with the field strength of $\sim 10^{-9}$G at the present time can be induced.Comment: 18 pages, 6 figures, version accepted for publication in Eur. Phys. J.

Barriers and facilitators to provide effective pre-hospital trauma care for road traffic injury victims in Iran: a grounded theory approach

BACKGROUND: Road traffic injuries are a major global public health problem. Improvements in pre-hospital trauma care can help minimize mortality and morbidity from road traffic injuries (RTIs) worldwide, particularly in low- and middle-income countries (LMICs) with a high rate of RTIs such as Iran. The current study aimed to explore pre-hospital trauma care process for RTI victims in Iran and to identify potential areas for improvements based on the experience and perception of pre-hospital trauma care professionals. METHODS: A qualitative study design using a grounded theory approach was selected. The data, collected via in-depth interviews with 15 pre-hospital trauma care professionals, were analyzed using the constant comparative method. RESULTS: Seven categories emerged to describe the factors that hinder or facilitate an effective pre-hospital trauma care process: (1) administration and organization, (2) staff qualifications and competences, (3) availability and distribution of resources, (4) communication and transportation, (5) involved organizations, (6) laypeople and (7) infrastructure. The core category that emerged from the other categories was defined as "interaction and common understanding". Moreover, a conceptual model was developed based on the categories. CONCLUSIONS: Improving the interaction within the current pre-hospital trauma care system and building a common understanding of the role of the Emergency Medical Services (EMS) emerged as key issues in the development of an effective pre-hospital trauma care process