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Quantum dots consisting of an axial Zn0.97Mg0.03Te insertion inside a large-bandgap Zn0.9Mg0.1Te nanowire core coated with two radial shells: ZnSe/Zn0.9Mg0.1Te. The interface between dot and ZnSe shell is characterized by type-II band alignment.

Incorporation of Bi into GaAs-(Ga,Al)As-Ga(As,Bi) core-shell nanowires grown by molecular beam epitaxy is studied with transmission electron microscopy. Nanowires are grown on GaAs(111)B substrates with Au-droplet assisted mode. Bi-doped shells are grown at low temperature (300 {\deg}C) with a close to stoichiometric Ga/As flux ratio. At low Bi fluxes, the Ga(As,Bi) shells are smooth, with Bi completely incorporated into the shells. Higher Bi fluxes (Bi/As flux ratio ~ 4%) led to partial segregation of Bi as droplets on the nanowires sidewalls, preferentially located at the nanowire segments with wurtzite structure. We demonstrate that such Bi droplets on the sidewalls act as catalysts for the growth of branches perpendicular to the GaAs trunks. Due to the tunability between zinc-blende and wurtzite polytypes by changing the nanowire growth conditions, this effect enables fabrication of branched nanowire architectures with branches generated from selected (wurtzite) nanowire segments., Comment: 41 pages, 14 figures

Magnetic carbon activated (MAC) Fe3O4-loaded activated carbon was developed using termite feces and sulfuric acid as the carbon-modifying agent. The key point of the synthetic strategy was that the carbonization, activation and Fe3O4 loading were accomplished simultaneously, via thermic activation/magnetization. The adsorptive characteristics of the MAC for removal of Cr(VI) were investigated. Batch adsorption experiments were performed using both AC and MAC. The evaluation of the adsorption kinetics, isotherm, and thermodynamics was investigated. Adsorption of Cr(VI) onto MAC was highly pH dependent and was found to be optimum at pH 3.0. Nonlinear regression analysis revealed that the Sips isotherm model provides a better correlation for Cr(VI) adsorption onto MAC. The maximum adsorption capacities, at 25 °C, depends on the conditions of preparation of the adsorbent, and were noted to be 60 mg/g for AC and 35, 44 and 66 mg/g for MAC-600, MAC-700 and MAC-800, respectively. The pseudo second-order model best fit the adsorption kinetics. The magnetic property in MAC ensured easy separation of adsorbent using a magnet, after adsorption from the aqueous solution.

ZnTe/CdSe/(Zn,Mg)Te core/double-shell nanowires are grown by molecular beam epitaxy by employing the vapor-liquid-solid growth mechanism assisted with gold catalysts. A photoluminescence study of these structures reveals the presence of an optical emission in the near infrared. We assign this emission to the spatially indirect exciton recombination at the ZnTe/CdSe type II interface. This conclusion is confirmed by the observation of a significant blue-shift of the emission energy with an increasing excitation fluence induced by the electron-hole separation at the interface. Cathodoluminescence measurements reveal that the optical emission in the near infrared originates from nanowires and not from two dimensional residual deposits between them. Moreover, it is demonstrated that the emission energy in the near infrared depends on the average CdSe shell thickness and the average Mg concentration within the (Zn,Mg)Te shell. The main mechanism responsible for these changes is associated with the strain induced by the (Zn,Mg)Te shell in the entire core/shell nanowire heterostructure., Comment: 7 pages

In this paper, nano-hybrid particles of Ag@Fe2O3 based on O-carboxymethylchitosan were successfully synthesized using different reducing agents (NaBH4, sucrose) and without reducing agent. The smallest silver nanoparticles were those prepared without reducing agent (∼5±3nm). The average size of silver particles prepared with NaBH4 is around 5-15nm, and for samples prepared with sucrose, the average particle size is 10-25nm. The magnetization curves are roughly reversible, indicating that γ-Fe2O3 nanoparticles transit to a superparamagnetic state. Nanocomposites subjected to antimicrobial tests showed great antimicrobial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria, and good activity against the yeast Candida albicans and resistant strains of Staphylococcus aureus. The antibacterial behavior as a function of time was investigated in microbial growth kinetics, and the best nanocomposite was the one without reducing agent, which completely inhibited microbial growth for 48h.

Wstep. Bol jest doznaniem subiektywnym, a wystepujący w tracie choroby nowotworowej moze miec roznorodne pochodzenie. Pielegniarka odgrywa kluczową role w efektywności terapii przeciwbolowej prowadzonej na oddzialach szpitalnych. Cel pracy. Celem badan bylo poznanie opinii chorych leczonych na oddziale onkologicznym na temat roli pielegniarki w zwalczaniu bolu nowotworowego. Materialy i metody. W badaniach wzielo udzial 78 osob bedących pacjentami Oddzialu Onkologicznego BCO-SM w Bielsku-Bialej. W pracy uzyto dwoch narzedzi badawczych: autorskiego, anonimowego kwestionariusza ankiety oraz Numerycznej Skali Oceny Bolu (NRS). Uzyskane wyniki badan poddano analizie statystycznej, ktorą wykonano za pomocą pakietu statystycznego R 3.0.2. Do obliczen uzyto testow t-Studenta oraz chi-kwadrat. We wszystkich obliczeniach statystycznych przyjeto poziom istotności p < 0,05. Zmienne ilościowe opisywano za pomocą wartości średniej, odchylenia standardowego (SD). Zmienne jakościowe opisywano za pomocą czestości wystąpien poszczegolnych wartości oraz rozkladu procentowego. Porownanie wartości zmiennych jakościowych w kilku grupach wykonano za pomocą testu chi-kwadrat lub, tam gdzie w tabelach pojawialy sie male wartości oczekiwane, dokladnego testu Fishera. Wyniki. Pacjenci wysoko ocenili role pielegniarki w terapii przeciwbolowej. Wiekszośc badanych pacjentow uwaza, ze pielegniarka reaguje szybko, jest kompetentna, a informacje udzielane przez nią są rzetelne. Wnioski. 1. Dane spoleczno-demograficzne chorych nie wplywają istotnie na ocene zachowania pielegniarek w zakresie reakcji na zglaszany przez chorych bol, regularnego podawania lekow przeciwbolowych czy rzetelnośc udzielanych przez pielegniarki informacji na temat terapii bolu. 2. Pacjenci niezaleznie od plci wykazywali podobne natezenie bolu nowotworowego. 3. Stopien natezenia bolu u chorych nie roznicuje istotnie reakcji pielegniarek.

Three series of glasses of the Li2O-FeO-V2O5-P2O5 system were thermally nanocrystallized and their microstructure was studied, at a nanometer resolution by transmission electron microscopy (TEM). Those observations were complemented by DTA and XRD studies on the same materials. It was shown that appropriate heating of the as-received glasses leads to formation of crystalline nanosize grains embedded in the glassy matrix. Average size of those grains reached even a few nm, was much smaller than that reported for LiFePO4-based nanostructured materials obtained by other methods. The crystal structure of most nanograins was identified as that of the LiFePO4 olivine, but some grains of the Nasicon-like Li3V2(PO4)3 phase were also present. The presence of both phases was confirmed independently by XRD patterns. Due to small size of crystalline grains (down to ca 5 nm) the interfacial regions around them occupy an important fraction of the total volume of the material and their properties can strongly influence the effective properties of the whole material. We have postulated that the defective nature of interfacial regions leads to an increased concentration of Fe2 +/Fe3 +, V4 +/V5 + or V3 +/V4 + aliovalent pairs, crucial for a small polaron hopping mechanism of the electronic transport, and to an enhanced electrical conductivity. The presence of highly conducting interfacial regions in the system where either the glass matrix and both crystalline phases (LiFePO4 and Li3V2(PO4)3) are very poor conductors is the main cause of the observed strong enhancement of the electrical conductivity of the heat-treated glasses of the Li2O-FeO-V2O5-P2O5 system.

The core-multishell wurtzite structure (In, Ga) As-(Ga, Al) As-(Ga, Mn) As semiconductor nanowires have been successfully grown on GaAs(111) B substrates using MBE technique. The nanowires cores we ...

Wurtzite CdTe and (Cd,Mn)Te nanowires embedded in (Cd,Mg)Te shells are grown by employing vapour-liquid-solid growth mechanism in a system for molecular beam epitaxy. A combined study involving cathodoluminescence, transmission electron microscopy and micro-photoluminescence is used to correlate optical and structural properties in these structures. Typical features of excitonic emission from individual wurtzite nanowires are highlighted including the emission energy of 1.65 eV, polarization properties and the appearance B-exciton related emission at high excitation densities. Angle dependent magneto-optical study performed on individual (Cd,Mn)Te nanowires reveals heavy-hole-like character of A-excitons typical for wurtzite structure and allows to determine the crystal field splitting, ΔCR. The impact of the strain originating from the lattice mismatched shell is discussed and supported by theoretical calculations.

Glassy analogs of two important cathode materials for Li-ion cells: V 2 O 5 and phosphoolivine LiFePO 4 were heat-treated in order to prepare nanocrystallized materials with high electronic conductivity of up to 7 × 10 −2 S cm −1 and ca 7 × 10 −3 S cm −1 at 25 °C, respectively. There is a clear correlation between the crystallization phenomena and the increase in the electrical conductivity for both groups of glasses. Electrochemical tests of heat-treated glasses of the V 2 O 5 –P 2 O 5 system, used as cathodes in lithium cells confirm their good gravimetric capacity and reversibility. Heat-treatment of glasses of the Li 2 O–FeO–V 2 O 5 –P 2 O 5 system also leads to a high increase in the conductivity and to formation of nanocrystalline grains in the glassy matrix, evidenced by HR-TEM images. The temperature dependence of the conductivity of these materials follows the Arrhenius formula. The presented results indicate that the overall increase in conductivity in nanocrystallized materials is due to good charge transport properties of their interfacial regions.

Structural analysis of epitaxial layers of the (Ga,Mn)(Bi,As) quaternary dilute magnetic semiconductor (DMS), together with investigations of their magnetotransport properties, has been thoroughly performed. The obtained results are compared with those for the reference (Ga,Mn)As layers, grown under similar conditions, with the aim to reveal an impact of Bi incorporation on the properties of this DMS material. Incorporation of Bi into GaAs strongly enhances the spin-orbit coupling strength in this semiconductor, and the same has been expected for the (Ga,Mn)(Bi,As) alloy. In turn, importantly for specific spintronic applications, strong spin-orbit coupling in ferromagnetic systems opens a possibility of directly controlling the direction of magnetization by the electric current. Our investigations, performed with high-resolution X-ray diffractometry and transmission electron microscopy, demonstrate that the (Ga,Mn)(Bi,As) layers of high structural quality and smooth interfaces can be grown by means of the low-temperature molecular-beam epitaxy method, despite a large difference between the sizes of Bi and As atoms. Depending on the applied buffer layer, the DMS layers can be grown under either compressive or tensile misfit strain, which influences their magnetic properties. It is shown that even small 1% Bi content in the layers strongly affects their magnetoelectric properties, such as the coercive field and anisotropic magnetoresistance.

Nearly 30% increase of the ferromagnetic phase transition temperature has been achieved in strained MnAs nanocrystals embedded in a wurtzite GaAs matrix. Wurtzite GaAs exerts tensile stress on hexagonal MnAs nanocrystals, preventing a hexagonal to orthorhombic structural phase transition, which in the bulk MnAs is combined with the magnetic one. This effect results in a remarkable shift of the magneto-structural phase transition temperature from 313 K in the bulk MnAs to above 400 K in the tensely strained MnAs nanocrystals. This finding is corroborated by the state of the art transmission electron microscopy, sensitive magnetometry and the first-principles calculations. The effect relies in defining a nanotube geometry of molecular beam epitaxy grown core-multishell wurtzite (Ga,In)As/(Ga,Al)As/(Ga,Mn)As/GaAs nanowires where the MnAs nanocrystals are formed during the thermal-treatment-induced phase separation of wurtzite (Ga,Mn)As into the GaAs:MnAs granular system. Such a unique combination of two types of hexagonal lattices provides possibility of attaining quasi-hydrostatic tensile strain in MnAs (impossible otherwise), leading to the substantial ferromagnetic phase transition temperature increase in this compound., Comment: 31 pages, 13 figures

SnTe topological crystalline insulator nanowires have been grown by molecular beam epitaxy on graphene/SiC substrates. The nanowires have cubic rock-salt structure, they grow along [001] crystallographic direction and have four sidewalls consisting of {100} crystal planes known to host metallic surface states with Dirac dispersion. Thorough high resolution transmission electron microscopy investigations show that the nanowires grow on graphene in the van der Walls epitaxy mode induced when the catalyzing Au nanoparticle mixes with Sn delivered from SnTe flux, providing liquid Au-Sn alloy. The nanowires are totally free from structural defects, but their {001} sidewalls are prone to oxidation, which points out on necessity of depositing protective capping in view of exploiting the magneto-electric transport phenomena involving charge carriers occupying topologically protected states., Comment: 7 pages, 8 figures

Highly conducting olivine-like materials have been prepared by thermal nanocrystallization of a series of glassy lithium-iron-vanadate-phosphates, of the compositions close to that of the LiFePO 4 olivine, with only small amounts of vanadium additive. It was found out that their thermal treatment up to a certain temperature, from the 460 and 500 °C range, optimized for each composition separately, led to: i) a considerable and irreversible conductivity increase by a factor of up to 10 6 (at room temperature) and ii) a change in the microstructure, from purely amorphous to nanocrystalline (for samples with lower vanadium contents) or polycrystalline (for a sample with higher vanadium content). The conductivity enhancement was accompanied by a decrease in the activation energy from the initial value of ca 0.70 eV to ca 0.11 eV after nanocrystallization. STEM and HRTEM microscopy studies showed, that in the materials with lower vanadium content, the heat treatment leads to formation of very small (ca 10 nm) crystallites densely distributed inside the glassy matrices. For the material with higher vanadium content similar processing leads to crystallization with larger grains (over 100 nm). The increase in conductivity of the latter material was smaller, than in the former ones. The observed correlation between the improvement of the electrical properties and a microstructure of annealed samples was attributed to a substantial role of the interfacial regions in the electrical conduction. These defective interfacial regions contain an increased concentration of transition metal aliovalent ions, which can provide multiple channels for electronic hopping between: Fe 2 + and Fe 3 + , V 4 + and V 5 + , or V 3 + and V 4 + centers. As the volume fraction of the interfacial regions in the nanostructured (with 10 nm grains) material is much higher than in a coarse-grained one (over 100 nm), the effective conductivity of the former material is much higher than that of the latter one. 1

A detailed magneto-photoluminescence study of individual (Cd, Mn)Te/(Cd, Mg)Te core/shell nanowires grown by molecular beam epitaxy is performed. First of all, an enhancement of the Zeeman splitting due to sp-d exchange interaction between band carriers and Mn-spins is evidenced in these nanostructures. Then, it is found that the value of this splitting depends strongly on the magnetic field direction with respect to the nanowire axis. The largest splitting is observed when the magnetic field is applied perpendicular and the smallest when it is applied parallel to the nanowire axis. This effect is explained in terms of magnetic field induced valence band mixing and evidences the light hole character of the excitonic emission. The values of the light and heavy hole splitting are determined for several individual nanowires based on the comparison of experimental results to theoretical calculations.

In this paper, nano-hybrid particles of Ag@Fe

Scarcity of well-trained clinical tutors is a key constraint in integrating teaching of evidence-based medicine (EBM) into clinical activities. We developed a web-based educational course for clinical trainers to confidently teach EBM principles in everyday practice. Its e-learning modules defined the learning objectives and incorporated video clips of practical and effective EBM teaching methods for exploiting educational opportunities in six different clinical settings. We evaluated the course with clinical tutors in different specialties across six European countries using a questionnaire to capture learning achievement against preset objectives. Among 56 tutors, 47 participants (84%) improved their scores from baseline. The mean pre-course score was 69.2 (SD=10.4), which increased to 77.3 (SD=11.7) postcourse (p

CdTe nanowires with the average diameter of only 40 nm coated with (Cd,Mg)Te shells are grown using Au-catalyzed vapor-liquid-solid growth mechanism in a system for molecular beam epitaxy. High optical quality of individual nanowires is revealed by means of low temperature cathodoluminescence and micro-luminescence. It is found that, the optical emission spectrum consists mostly of the near band edge emission without any significant contribution of defect related luminescence. Moreover, the importance of surface passivation with (Cd,Mg)Te coating shells is demonstrated.

Evidence-based Medicine (EbM) was originally developed as a teaching tool for young doctors, but in Germany the last surveys among residents in 2009 and 2011 demonstrated that, across all topics, the largest deficits were seen in the field of EbM. One reason may be a deficit in customised offers for continuing medical education in EbM. In a randomised controlled trial with a wait-control design we investigated a possible gain in knowledge and the acceptance of an online course in EbM for first-year residents.All first-year residents at the Hospital of the Goethe University in Frankfurt received the offer to voluntarily take part in an online EbM course. The tutored course consisted of five modules according to the five steps of EbM, each module being complemented by practical tasks. The participants were randomised via telephone to the course right away or after a three-month waiting period. The primary endpoint (i.e., knowledge) was tested via two sets of 13 multiple choice questions before and after the course and after 6 and 12 months. The participants were asked to subjectively evaluate the course by using an A-F grading system and to semiquantitatively assess its level of difficulty; they were also asked to evaluate the usefulness of its content in their clinical setting.114 out of the 120 randomised participants took part. After 3 months the immediate intervention group (n=58) achieved a median of 10 (95 % confidence interval 10 to 11) correct answers following the course, whereas the waiting intervention group only received a median of 4 (95% confidence interval 4 to 5) correct answers after the three month waiting period (p ≤ 0.0001). The median gain in knowledge for both groups throughout the course was 5 correct answers (p ≤ 0.0001), and this proved to remain constant within a twelve month period. Six months after the course, this course was rated as clinically useful by 96.4 % of the participants, and 38.1% stated that they would volunteer again in further teaching activities. The course received a median grade of B.A German online EbM course for first-year residents leads to a remarkable and sustainable gain in knowledge, is well marked, and its contents were regarded as clinically relevant. This tutored practical course is applicable to various settings and could provide an important contribution to EbM residency programs.

Background Evidence based medicine (EBM) is considered an integral part of medical training, but integration of teaching various EBM steps in everyday clinical practice is uncommon. Currently EBM is predominantly taught through theoretical courses, workshops and e-learning. However, clinical teachers lack confidence in teaching EBM in workplace and are often unsure of the existing opportunities for teaching EBM in the clinical setting. There is a need for continuing professional development (CPD) courses that train clinical trainers to teach EBM through on-the-job training by demonstration of applied EBM real time in clinical practice. We developed such a course to encourage clinically relevant teaching of EBM in post-graduate education in various clinical environments. Methods We devised an e-learning course targeting trainers with EBM knowledge to impart educational methods needed to teach application of EBM teaching in commonly used clinical settings. The curriculum development group comprised experienced EBM teachers, clinical epidemiologists, clinicians and educationalists from institutions in seven European countries. The e-learning sessions were designed to allow participants (teachers) to undertake the course in the workplace during short breaks within clinical activities. An independent European steering committee provided input into the process. Results The curriculum defined specific learning objectives for teaching EBM by exploiting educational opportunities in six different clinical settings. The e-modules incorporated video clips that demonstrate practical and effective methods of EBM teaching in everyday clinical practice. The course encouraged focussed teaching activities embedded within a trainer's personal learning plan and documentation in a CPD portfolio for reflection. Conclusion This curriculum will help senior clinicians to identify and make the best use of available opportunities in everyday practice in clinical situations to teach various steps of EBM and demonstrate their applicability to clinical practice. Once fully implemented, the ultimate outcome of this pilot project will be a European qualification in teaching EBM, which will be used by doctors, hospitals, professional bodies responsible for postgraduate qualifications and continuing medical education.

Background Teaching of evidence-based medicine (EBM) has become widespread in medical education. Teaching the teachers (TTT) courses address the increased teaching demand and the need to improve effectiveness of EBM teaching. We conducted a systematic review of assessment tools for EBM TTT courses. To summarise and appraise existing assessment methods for teaching the teachers courses in EBM by a systematic review. Methods We searched PubMed, BioMed, EmBase, Cochrane and Eric databases without language restrictions and included articles that assessed its participants. Study selection and data extraction were conducted independently by two reviewers. Results Of 1230 potentially relevant studies, five papers met the selection criteria. There were no specific assessment tools for evaluating effectiveness of EBM TTT courses. Some of the material available might be useful in initiating the development of such an assessment tool. Conclusion There is a need for the development of educationally sound assessment tools for teaching the teachers courses in EBM, without which it would be impossible to ascertain if such courses have the desired effect.