bluuebunny/crossref_metadata_2025 huggingface dataset:
Biogenic CuFe2O4 magnetic nanoparticles as a green, reusable and excellent nanocatalyst for acetylation reactions under solvent-free conditions
Authors: Chutia Rituparna , Chetia Bolin
Published: August 2018

A convenient green method has been developed for the synthesis of biogenic CuFe2O4 magnetic nanoparticles using tea extracts within a very short reaction time.
Fabrication of a novel electrochemical sensor for the determination of water in some organic solvents based on naphthalene conducting polymers
Authors: Bakhtiari Haft Lang Safoura , Azizi Elmira , Arjomandi Jalal , Nematollahi Davood , Massah Ahmad Reza
Published: August 2018

We fabricated a novel water sensor for some organic solvents based on a modified gold electrode with naphthalene conducting polymers.
Preparation of hydrido [CNC]-pincer cobalt complexes via selective C–H/C–F bond activation and their catalytic performances
Authors: Yang Fei , Wang Yangyang , Lu Faguan , Xie Shangqing , Qi Xinghao , Sun Hongjian , Li Xiaoyan , Fuhr Olaf , Fenske Dieter
Published: August 2018

[CNC]-pincer Co hydrides were synthesized via selective C–H/C–F activation and catalyzed hydrosilylation of carbonyl compounds.
Tunable aggregation of gold-silica janus nanoparticles to enable contrast-enhanced multiwavelength photoacoustic imaging in vivo
Authors: Park Ji Hun , Dumani Diego S. , Arsiwala Ammar , Emelianov Stanislav , Kane Ravi S.
Published: August 2018

Tunable aggregation of gold-silica janus nanoparticles is utilized to enable contrast-enhanced multiwavelength photoacoustic imaging in vitro/in vivo.
Reversible resistive switching behaviour in CVD grown, large area MoOx
Authors: Rahman Fahmida , Ahmed Taimur , Walia Sumeet , Mayes Edwin , Sriram Sharath , Bhaskaran Madhu , Balendhran Sivacarendran
Published: August 2018

Reversible resistive switching behaviour is observed in MoOx memory devices, at relatively low set/reset voltages, with switching ratios exceeding 103.
Enhanced capture and release of circulating tumor cells using hollow glass microspheres with a nanostructured surface
Authors: Dong Ziye , Yu Dan , Liu Qingye , Ding Zhenya , Lyons Veronica J. , Bright Robert K. , Pappas Dimitri , Liu Xinli , Li Wei
Published: August 2018

NSHGMS can isolate and recover circulating tumor cells in blood with shorter processing time, enhanced capture efficiency and lower detection limit.
Band gap reduction in van der Waals layered 2D materials via a de-charge transfer mechanism
Authors: Zhang Chunxiao , Huang Huaqing , Ni Xiaojuan , Zhou Yinong , Kang Lei , Jiang Wei , Chen Haiyuan , Zhong Jianxin , Liu Feng
Published: August 2018

The critical role of de-charge transfer in tuning the band gap of layered 2D materials.
EGFR-targeted liposomal nanohybrid cerasomes: theranostic function and immune checkpoint inhibition in a mouse model of colorectal cancer
Authors: Li Yuan , Du Yang , Liang Xiaolong , Sun Ting , Xue Huadan , Tian Jie , Jin Zhengyu
Published: August 2018

The epidermal growth factor receptor (EGFR) is a major target for the treatment of colorectal cancers (CRCs), and programmed death ligand-1 (PD-L1) is an attractive target for CRC immunotherapy.
Divergent synthesis of new α-glucosidase inhibitors obtained through a vinyl Grignard-mediated carbocyclisation
Authors: Knudsen Ida M. B. , Hedberg Christinne , Ladefoged Lucy Kate , Ide Daisuke , Brinkø Anne , Eikeland Espen Z. , Kato Atsushi , Jensen Henrik H.
Published: August 2018

Four new α-glucosidase inhibitors have been synthesised through 5–8 synthetic steps from a common synthetic intermediate obtained through a recently developed carbocyclisation.
Structure and behaviour of vesicles in the presence of colloidal particles
Authors: Jaggers Ross W. , Bon Stefan A. F.
Published: August 2018

A review of the structural changes and behaviour of synthetic vesicles when they are exposed to colloidal particles.
Complexity analysis of flexible transmitter digital signal processing for terabit (40 × 50G) four‐level pulse amplitude modulation transmission
Authors: Ranzini S.M. , Rossi S.M. , Figueiredo R.C. , Franz L.V. , Chiuchiarelli A.
Published: August 2018

The authors propose a transmitter digital filter for joint optimisation of signal pulse shaping and chromatic dispersion pre‐compensation, providing a detailed analysis of the architecture complexity. Experimental transmission of 40 × 50G channels (28 Gbaud four‐level pulse amplitude modulation) over up to 110 km uncompensated standard single mode fibre with low‐bandwidth hardware is demonstrated.
AMC loaded folded dipole with heart‐shaped radiation pattern
Authors: Mostafa M.M. , Abuelfadl T.M. , Safwat A.M.E.
Published: August 2018

This Letter presents a novel pseudo‐omnidirectional antenna that is appropriate for wide beam applications, e.g. handheld devices, along with a reduced back radiation that suits wearable applications as well. The design consists of a horizontal omnidirectional antenna placed on a proposed artificial magnetic conductor (AMC) surface that enhances the gain in the broadside direction, reduces the back radiation, and enables good radiation in the side directions. A 5 GHz folded dipole on a 2 × 2 AMC array surface is designed and characterised. Simulations and measurements, which are in a very good agreement, show that the radiation has a heart‐shaped pattern, with a front to back ratio of >13 dB, a front to side ratio of <2.5 dB, and a half‐power beam width of >230°.
Visual glare limits of HDR displays in medical imaging
Authors: Rizzi Alessandro , Barricelli Barbara Rita , Bonanomi Cristian , Albani Luigi , Gianini Gabriele
Published: August 2018

Emerging display technologies are proposing monitors for medical imaging with an extended dynamic range of luminance. Those devices offer the opportunity to extend the range of visual information displayed, but the limits of the human visual system (HVS) in perceiving such information can cancel the advantages. To investigate this problem, we present a set of experiments, to assess the visual response of the HVS to controlled high dynamic range (HDR) content. They analyse the effects of glare. Using a typical HDR display, tailored for medical imaging applications, they first study the dependence of the visible dynamic range from the inter‐ocular glare, induced by different backgrounds, then the effect of glare on the detection of test elements on medical radiographic images. Finally, they assess the influence of luminance‐equivalent backgrounds with different structure in the detection of test patches. The results of the experiments confirm the glare as a major player in influencing visual information detection. Glare has a significant impact in limiting the amount of visual information actually perceived, consequently limiting analysis capabilities of such images. This confirms the importance of investigating and considering the characteristics of human vision in the design and test of HDR imaging systems.
Nonthermal emission from high-mass microquasar jets affected by orbital motion
Authors: Molina E. , Bosch-Ramon V.
Published: August 2018

Context. The stellar wind in high-mass microquasars should interact with the jet. This interaction, coupled with orbital motion, is expected to make the jet follow a helical, nonballistic trajectory. The jet energy dissipated by this interaction, through shocks for example, could lead to nonthermal activity on scales significantly larger than the system size.

Aims. We calculate the broadband emission from a jet affected by the impact of the stellar wind and orbital motion in a high-mass microquasar.

Methods. We employ a prescription for the helical trajectory of a jet in a system with a circular orbit. Subsequently, assuming electron acceleration at the onset of the helical jet region, we compute the spatial and energy distribution of these electrons, and their synchrotron and inverse Compton emission including gamma-ray absorption effects.

Results. For typical source parameters, significant radio, X- and gamma-ray luminosities are predicted. The scales on which the emission is produced may reduce, but not erase, orbital variability of the inverse Compton emission. The wind and orbital effects on the radio emission morphology could be studied using very long baseline interferometric techniques.

Conclusions. We predict significant broadband emission, modulated by orbital motion, from a helical jet in a high-mass microquasar. This emission may be hard to disentangle from radiation of the binary itself, although the light curve features, extended radio emission, and a moderate opacity to very high-energy gamma rays, could help to identify the contribution from an extended (helical) jet region.
Comparative study of deterioration of composite due to ice formation using strain, electromechanical impedance and guided waves
Authors: Soman Rohan , Malinowski Pawel , Ostachowicz Wieslaw
Published: August 2018

Glass fibre reinforced plastic (GFRP) composites are finding increasing application in aerospace structures. The monitoring of these structures is not only necessary but also mandatory by the safety codes. The present state of the art allows isolation of damage and the quantification of damage is the next challenge. The quantification may allow for better maintenance scheduling and as a result lower downtime for airplanes, which makes it significant in the aerospace discipline. It is known that the moisture absorption in the composites affects its mechanical properties. The moisture can interact with the composite sample in the gaseous, liquid or solid phase. The mechanism for deterioration of the composite due to the moisture depends on the phase in which the interaction occurs. The paper thus investigates the interaction of water absorbed by the sample in the solid phase. The GFRP sample is exposed to low temperatures after the ingress of the moisture. The sample is studied using three distinct damage detection methods namely, Electromechanical Impedance technique (EMI), Guided waves method (GW) and NA based technique based on measured strains. The aim of the research is to compare the performance of the three methods for the assessment of the deterioration of the composite samples due to ice. The EMI, GW and strain based method have been shown to be sensitive to moisture induced deterioration. In addition to the detection of deterioration, the use of measured strains provides an intuitive way for the quantification of the moisture induced deterioration in the sample.
Non-destructive Methods for Damage Assessment of Composite Sandwich Structures
Authors: Bělský Petr , Kadlec Martin
Published: August 2018

Sandwich structures are capable of absorbing large amounts of energy under impact loads which results in high structural crashworthiness. Comparison of detection capabilities of selected C-scan NDT methods applicable for inspections of sandwich structures was performed using water-squirt, air-coupled and pitch-catch ultrasonic techniques, supplemented by laser shearography. Test results have shown that water-squirt and pitch-catch techniques are the most suitable methods for the core damage evaluation. Air-coupled method showed lower sensitive for detection of some artificial defects and impact damages in honeycomb sandwiches when unfocused transducers were used. The combination of the presented methods was able to reveal most of the defects.
A numerical investigation of the effect of preform length for the fabrication of 1.5Lt PET bottle through the injection stretch blow molding process
Authors: Lontos A. , Gregoriou A.
Published: August 2018

This study carries the numerical effort for the investigation of effect of preform length on the final product wall thickness distribution. For the investigation, three different preform length cases were taken under consideration. Preform A, preform B and preform C of length 144.75mm, 165.7mm and 186.65mm respectively. All the preforms were stretched up to a same critical point respect to mold length so that the axial deformation during blowing was fair for all the preform cases. Blowing conditions were the same for all cases. The stretching period for each case was set in accordance to the to the limit of critical stretching point. The mass of all preform cases was 58.33grams. It was found that preform B and C result in more uniform thickness distribution. The optimum results are given by preform C, since the resulting product appears the less spots with excess usage of raw material. The heavier bottle bottom region resulting from preform C enhances the steadiness of the bottle.
Hybrid superabsorbent polymer networks (SAPs) encapsulated with SiO2 for structural applications
Authors: Kanellopoulou Irene , Karaxi Evangelia K. , Karatza Anna , Kartsonakis Ioannis A. , Charitidis Costas
Published: August 2018

In this work, materials that as additives in cement promote self-sealing/healing properties by the gradual release of water they absorb were synthesized, characterized and evaluated. Specifically, hybrid SAPs that absorb high ammounts of water encapsulated with SiO2 that facilitates their incorporation in the matrix since it improves their chemical affinity were investigated. The structure and morphology of the fabricated SAPs were characterized analytically and confirmed the synthesis of P(MAA-co-EGDMA)@SiO2 nanocomposite. Its particle size is expected to reduce the size of the pores formed due to the absorbing/desorbing water process during the mixing and curing of cement. Moreover, the water absorbance of the above mentioned material as well as its ability to maintain its original structure during subsequent cycles of absorbing/desorbing water from different mediums and specifically from distilled water (DW) and cement slurry filtrate (CS) were evaluated. CS was chosen to mimic the cementitious environment considering the presence of various ions and its pH value (~ 12). The results revealed that the absorption ratio of P(MAA-co-EGDMA)@SiO2 in DW and CS was higher than 1500 wt.% its original dry weight, while SEM pictures proved that the hybrid SAPs maintained their structure after the water absorption tests.
A Tribological Simulation for a Typical Carbon Coated AFM Cantilever Interacting with a Monolayer Graphene Sheet
Authors: Grigoriadis Kyriakos , Palaiologos Alexandros , Zavos Anastasios , Nikolakopoulos Pantelis G.
Published: August 2018

This study aims on the dynamic and tribological characterization of a Single Layer Graphene Sheet (SLGS) including the effects of a graphene cantilever’s deflection. A 10 x 10 nm graphene model is developed, which is modally analyzed for both Zigzag and Armchair lattices. A typical Atomic Force Microscope (AFM) cantilever with carbon coated tip is also modeled during the simulation. The friction forces applied on the tip during its movement can be evaluated. The real contact area is characterized as the carbon atom tip is interlinked with the graphene atoms via the Lennard-Jones model. This study confirmed that the deformation of the AFM cantilever, is important to predict more accurately the tribological behaviour of graphene and the effect of its lattice orientation to its frictional properties. Therefore, this simulation provides an interesting way to understand the complex interaction between the cantilever tip and the sample in different contact conditions.
Tribological behavior of heat treated CuCrZr alloy
Authors: Çelik Gülşah Aktaş , Atapek Ş. Hakan , Polat Şeyda
Published: August 2018

Optimal combination of strength, ductility and conductivity in CuCrZr alloy can be achieved by suitable heat treatment involving solution annealing at high temperature to dissolve alloying elements, water quenching to produce a super-saturated solid solution, and an aging treatment at an intermediate temperature to produce fine precipitates giving rise to high strength. In this study, Cu-1Cr-0.1Zr alloy was manufactured as cast material and following hot forging, solution annealing and aging were applied conventionally. In order to enhance the precipitation kinetics, solution annealed and quenched alloy was cold deformed and then aged at the same condition. Specimens obtained after (i) casting, (ii) conventional solution annealing and aging and (iii) aging after cold deformation were investigated in order to determine microstructural features, hardness and tribological properties. The results showed that while heat treatment process increased hardness the of cast specimen, it was enhanced further with deformation before aging. Besides hardness, tribological properties of the cast specimen were improved further by deformation before aging.
Microstructure characterisation of Inconel 718 after laser assisted turning
Authors: Chwalczuk Tadeusz , Przestacki Damian , Szablewski Piotr , Felusiak Agata
Published: August 2018

The paper presents the discussion about the possibility of optimising heating and cutting parameters for turning under laser assisted machining (LAM) conditions. The samples of Inconel 718 after annealing and ageing were used. The laser heating experiments were carried out on the stand equipped with the CO2 molecular laser. Characterisation of samples was performed by an optical microscope, hardness measurements, scanning electron microscopy (SEM) to ensure the exact depth of heat affect zone range and to optimised further cutting parameters. Different absorbing layers for laser beam impact improvement were tested. Turning trials were performed with constant cutting speed vc = 28 m/min and feed f = 0,2 mm/rev. The influence of depth of cut ap on microstructure and its properties were investigated. It was proven that for sequential LAM dendritic structure appears in the laser affected zone of the Ni-based alloy. Such microstructures cause better machinability of Inconel 718 due to surface softening.
Failure behavior of PA12 based SLS lattice structure with macro-porosity
Authors: Gümüs Serap , Lackner Juergen M. , Polat Şeyda , Kraschitzer Wolfgang , Hanning Hermann , Bayram Alperen , Kaya Mesut , Çallı Metin , Alkan Attila
Published: August 2018

Nowadays the demands of high reliability, high mechanical properties under fatigue loading and ultra-light-weight design are topics of pressing needs in different industry applications. Additive manufacturing technique has great potential to meet such demands and Selective Laser Sintering (SLS) is the dominantly used one due to its versatility in material design, construction and the much higher achievable mechanical strength compared to its competing technologies like fused filament fabrication. In this study, it is aimed to give an insight to the fracture behaviour of SLS produced lattice structure with macro-porosity under compression load. The stress type and distribution on the lattice structure under compression load are anisotropic because of the unit cell topologies and the anisotropic processing condition. Therefore, different kinds of fracture types are evident depending on the region of the fractured struts.
THE REACTIONS OF THE «BEAM – FOUNDATION» SYSTEM TO THE SUDDEN CHANGE OF THE BOUNDARY CONDITIONS
Authors: Gordon Vladimir A. , Pilipenko Olga V. , Trifonov Vladimir A.
Published: August 2018

The authors constructed a mathematical model of a dynamic process in a loaded beam on the elastic Winkler foundation in a sudden formation of a defect in the form of a change in the boundary conditions. The solution of the static problem of bending of the beam pinched at the ends served as the initial condition for the process of forced vibrations hinged supported at the ends of a beam, which arose after a sudden break in the connections that prevented the rotation of the end sections. The authors determined the dynamic increments of stresses in a beam for various combinations of a beam and foundation parameters.
High cycle fatigue life estimation of AlSi10Mg processed by laser powder bed fusion
Authors: Hovig Even W. , Azar Amin S. , Sunding Martin F. , Sørby Knut , M'hamdi Mohammed , Andreassen Erik
Published: August 2018

Fatigue life is known to be dependent on the surface properties of the material. Surface roughness provokes local stress concentration and cause crack initiation even at minute cyclic loads. In laser powder bed fusion, the as-built surfaces show variable roughness depending on the orientation of the specimens with respect to the build plate. In order to analyse the effect of build angle on surface properties, flat tensile specimens were produced from an AlSi10Mg alloy in a Concept Laser M2 Cusing machine. Seven specimens were arranged from flat to perpendicular with respect to the build plate at 15° intervals. The as-built surface topography of each specimen was characterised by white light interferometry. Two methods for calculating the stress concentration factor for high cycle fatigue simulation were developed. The presence of subsurface porosity was a crucial factor in expanding the stress concentration as demonstrated by finite element analysis.
Using the Hybrid Metal Extrusion & Bonding (HYB) Process for Butt Welding of 4 mm Plates of AA6082-T6
Authors: Sandnes Lise , Grong Øystein , Torgersen Jan , Berto Filippo
Published: August 2018

Hybrid Metal Extrusion & Bonding is a new solid state joining technique developed for aluminium alloys. By the use of filler material addition and plastic deformation sound joints can be produced at operational temperatures below 400 °C. This makes the HYB process more flexible and less vulnerable to defects compared to conventional solid state processes. Here, we present the results form an exploratory investigation of the mechanical integrity of a 4 mm AA6082-T6 HYB joint, covering both hardness, tensile and Charpy V-notch testing of different weld zones. The joint is found to be free from internal defects like pores, cavities and kissing bonds. Still, a soft heat affected zone (HAZ) is present. The joint yield strength is 54 % of the base material, while the corresponding joint efficiency is 66%. Therefore, there is a potential for further optimization of the HYB process. This work is now in progress.
Development of the “High Pressure Repair Dome” system for in-situ high performance repair of aeronautic structures
Authors: Gallo Nicola , Pappadá Silvio , Raganato Umberto , Corvaglia Stefano
Published: August 2018

As the use of composites for high-performance structures for aerospace applications is constantly increasing, together with the complexity and scale of such structures, an increasingly effort is carried out for the development of advanced techniques for composites structural repair. Mechanical loads and environmental conditions often cause composite damages. If material damage is not extensive, structural repair is the most cost-effective solution. Composite patches can be mechanically fastened, adhesively bonded or co-cured. Bonding or co-curing process provides enhanced stress transfer mechanisms, joint efficiencies and aerodynamic performance. In this paper an innovative and reliable technique to repair damaged composite aeronautical components, named High Pressure Repair Dome (HPRD), is shown. The innovative aspect of this solution is the possibility to bond or co-cure a composite prepreg patch under a pressurized dome, thus using a prepreg compatible with the composite structure. HPRD was developed to allow in-situ repairing on full-scale structures, with the possibility of an accurate control of the parameters of the curing cycle. The advantages and performance of HPRD approach will be discussed and compared with traditional techniques, describing the results achieved and the activity on-course for the full industrialization of this system.
Improving the cutting performance of coated tools via appropriate pre- and post-treatments
Authors: Bouzakis Konstantinos , Skordaris Georgios , Bouzakis Emmanuil , Kotsanis Tilemachos
Published: August 2018

The cutting performance of PVD coated tools can be significantly improved by appropriate pre- and post- treatments of the substrates and coated surfaces respectively. Substrate pre-treatments aim, among others, at improving the coating adhesion. In this way, lower coating loads develop during cutting leading to a decelerated wear evolution. Furthermore, the potential to increase the wear resistance of coated tools via micro-blasting is presented. Micro-blasting parameters such as of grain material, pressure, dry or wet etc., affect significantly the superficial coatings' hardness and brittleness and in this way their wear behaviour. To check the effectiveness of all these methods, innovative coating's characterization procedures providing information concerning the film and substrate properties as well as adhesion are applied, thus reducing the required experimentation time.
Fracture analysis of a cooling water pump shaft
Authors: Papageorgiou Dimitris G. , Kovsenoglou Kyriakos A. , Bournelis Petros , Medrea Carmen
Published: August 2018

Six shaft failures were encountered in a centrifugal water pump, part of the engine cooling system of a container ship. The last two failed pieces were received for analysis. A detailed study was carried out to determine the cause of the component failures. Historical data was collected, visual inspection was performed and a photographic file was created. The pieces were measured in order to record their general features and a 3-D model was generated. Hardness measurements were carried out. Microstructure was examined by means of light microscopy. A finite element simulation was conducted in order to determine the stress topology and to identify possible critical areas. Chemical analysis was carried out. The shafts were manufactured onboard, from AISI 304 stainless steel. The low hardness of both pieces indicates insufficient mechanical properties. Microstructural examination showed characteristic microstructure of coarse austenite. The presence annealing process derived twins and limited grain-boundary carbide precipitates were verified. The shafts failed due to torsional fatigue. Fracture initiated at the keyway on the propeller side as it was predicted from the finite elements analysis. Material selection material has and poor machining were found to be the main cause of failure. Appropriate recommendations were provided.
Surface treatment of tool steels against galling failure
Authors: Psyllaki Pandora , Stamatiou Konstantinos , Iliadis Iason , Mourlas Athanasios , Asteris Panagiotis , Vaxevanidis Nikolaos
Published: August 2018

In the present study two highly alloyed steel grades, intended for cold working applications, were subjected to plane-contact, nonlubricating sliding friction testing in order to estimate the working regions (applied pressure and sliding velocity) that are governed by mild, moderate and severe wear mechanisms, before and after nitrocarburizing. For this purpose, both tool steel grades were initially pre-subjected to the proper heat treatments, in order to achieve a final bulk hardness of 40, 50 and 60 HRC whereas, after heat treatment, half of the material specimens were further subjected to nitrocarburizing surface treatment. The comparative experimental study of heat-treated and heat-/ surface-treated grades within a wide range of applied pressure and sliding velocity values, in combination to the development of a relevant Artificial Neural Network, allowed to determine the areas of recommended operation of such tribosystems. In all cases, the positive influence of the post-hardening surface treatment was proved; further work is in progress to generalize these preliminary results and establish the relevant wear maps correlating the wear lifetime, the hardening levels and the surface treatment to the operational plane sliding conditions.
Failure analysis of two cold-working cutting tools. Case studies
Authors: Medrea Carmen , Fragkos-Livanios Leonidas , Giannakopoulos Kostas I. , Statharas Dimitris
Published: August 2018

The study examines the dramatic drop in the efficiency of a cutting tool. The specific tool is part of machine used for cutting envelopes of paper for medical products packaging. Two similar pieces, selected after breaking down in service, were examined in depth. Historical data was collected. The tool temperature range during operation and the material hardness were measured. The fracture surfaces as well as the surrounding areas were carefully inspected. Chemical analysis was performed in order to identify the tool and coating materials. Results showed that components were made of different steels: D2 and Vanadis 6. The coating material also differs. Samples were selected and prepared for optical and electron microscopy. The condition of the cutting edges and the heat-treated microstructure were considered. Thickness, quality and homogeneity of the coatings were also inspected. Both tools failed by fatigue mode under different conditions. The fracture mechanism and its principal causes are discussed. The reasons of failure for both cutting tools are examined and compared. Poor designs associated with improper handling have led to the components breakage. Appropriate recommendations are given in order to eliminate similar situations and to improve the cutting performance.
End Node Security and Trust vulnerabilities in the Smart City Infrastructure
Authors: Fournaris Apostolos P. , Lampropoulos Konstantinos , Koufopavlou Odysseas
Published: August 2018

As cities gradually introduce intelligence in their core services and infrastructure thus becoming “smart cities”, they are deploying new Information Technology devices in the urban grid that are interconnected to a broad network. The main focus of widely implemented smart cities' services was the operation of sensors and smart devices across city areas that need low energy consumption and high connectivity. However, as 5G technologies are gradually been adopted in the smart city infrastructure thus solving that problem, the fundamental issue of addressing security becomes dominant. While latest network topologies and standards include security functions thus giving an illusion of security, there is little focus on the fact that many smart city end nodes cannot realize all security specifications without additional help. In this paper, we discuss briefly smart city security issues and focus on problem and security requirement that need to be address in the smart city end nodes, the sensors and actuators deployed within the city's grid. In this paper, attacks that cannot be thwarted by traditional cybersecurity solutions are discussed and countermeasures based on hardware are suggested in order to achieve a high level of trust. Also, the danger of microarchitectural and side channel attacks on these devices is highlighted and protection approaches are discussed.
Gicht und Calciumpyrophosphat-Dihydrat-Arthropathie („Pseudogicht“) – ein Update
Authors: Reuss-Borst Monika , Tausche Anne-Kathrin
Published: August 2018

The metabolic diseases gout and calciumpyrophosphate deposition (CPPD) (formerly: chondrocalcinosis/pseudogout) are crystal arthropathies which are caused by crystals in synovial fluid and in the case of gout also in periarticular structures. Today, in particular gout is considered as an auto-inflammatory process since phagocytosis of monosodium urate crystals by monocytes/macrophages results in the activation of the innate immune system by activation of the NRLP3-Inflammasome and consecutive secretion of the key cytokine interleukin-1ß and other pro-inflammatory cytokines. The prevalence of both crystal arthropathies rises with increasing age of patients. Most often they present clinically as an acute monarthritis of different locations. Beside typical clinical presentation, performance of ultrasonography, conventional X-Ray of joints and under special circumstances dual-energy-computer tomography could be also helpful diagnostic tools. There are EULAR guidelines describing the diagnostic algorithm for making right diagnosis. The arthrocentesis with microscopic detection of crystals is established diagnostic gold standard. Whereas crystals of monosodium urate could be very clearly be seen as relatively large intra- and extracellular needles with a strong birefringence in polarized light microscopy the detection of CPPD-crystals is more difficult. Those crystals are much smaller, showing weaker birefringence and are sometimes only seen with ordinary light microscopy. As both crystal diseases are mediated by IL-1 driven processes, the therapeutic intervention first target the acute inflammation consisting in colchicine, NSAIDs and glucocorticoids. Secondarily, in gout there are well established causal therapies to lower effectively serum urate levels below the target of 6 mg/dL (360 µmol/l). Unfortunately, those causal therapeutic options are still lacking in CPPD.
Vom Aktionsprogramm über die Bundesinitiative zur Bundesstiftung Frühe Hilfen
Authors: Paul Mechthild , Backes Jörg , Renner Ilona , Scharmanski Sara
Published: August 2018

Die Arbeit der Akteure in den Frühen Hilfen ist zentral für die Entwicklung von Kindern. Familienhebammen und Familien-Gesundheits- und Kinderkrankenpflegenden
kümmern sich seit mehr als zehn Jahren insbesondere darum, Familien dabei unterstützen, ihren Kindern einen guten Start ins Leben zu ermöglichen.
Das neue Mutterschutzgesetz
Authors: Weimer Tobias
Published: August 2018

Seit Januar 2018 gelten neue Regeln im Mutterschutz. Doch was hat sich wirklich geändert? Hier finden Sie die Antworten.
Geriatrisches Assessment Ernährung/Mangelernährung
Authors: Zemke Jens
Published: August 2018

„Deine Nahrungsmittel seien deine Heilmittel.“ Schon 400 Jahre vor Christi Geburt wusste der griechische Arzt und Philosoph Hippokrates um die Wichtigkeit
der Ernährungssituation für Gesundheit, Lebensqualität, Funktionalität und Selbstständigkeit (älterer) Menschen. Aktuell existieren zahlreiche Standards und
Leitlinien, welche wissenschaftliche Erkenntnisse nutzen, um die hochwertige und bedürfnisgerechte Ernährungsversorgung älterer Menschen zu gewährleisten.
Mangelernährung älterer Menschen in geriatrischen/gerontologischen Einrichtungen ist ein komplexes und multifaktorielles Problem, welches eine multidimensionale
und interdisziplinäre Herangehensweise erfordert (
Abb. 1
). Wichtig sind hierbei standardisierte Maßnahmen im Hinblick
auf Screening und Assessment des Ernährungsrisikos sowie strukturierte Handlungsanleitungen zur Kontrolle und Verbesserung der Ernährungssituation.
Synthesis, Antioxidant and In-Silico Studies of Potent Urease Inhibitors: N-(4-{[(4-Methoxyphenethyl)-(substituted)amino]sulfonyl}phenyl)acetamides
Authors: Abbasi Muhammad , Raza Hussain , Rehman Aziz , Siddiqui Sahahat , Nazir Majid , Mumtaz Ayesha , Shah Syed , Seo Sung-Yum , Hassan Mubashir
Published: August 2018

In this study, a new series of sulfonamides derivatives was synthesized and their inhibitory effects on DPPH and jack bean urease were evaluated. The in silico studies were also applied to ascertain the interactions of these molecules with active site of the enzyme. Synthesis was initiated by the nucleophilic substitution reaction of 2-(4-methoxyphenyl)-1-ethanamine (1) with 4-(acetylamino)benzenesulfonyl chloride (2) in aqueous sodium carbonate at pH 9. Precipitates collected were washed and dried to obtain the parent molecule, N-(4-{[(4-methoxyphenethyl)amino]sulfonyl}phenyl)acetamide (3). Then, this parent was reacted with different alkyl/aralkyl halides, (4a-m), using dimethylformamide (DMF) as solvent and LiH as an activator to produce a series of new N-(4-{[(4-methoxyphenethyl)-(substituted)amino]sulfonyl}phenyl)acetamides (5a-m). All the synthesized compounds were characterized by IR, EI-MS, 1H-NMR, 13C-NMR and CHN analysis data. All of the synthesized compounds showed higher urease inhibitory activity than the standard thiourea. The compound 5 f exhibited very excellent enzyme inhibitory activity with IC50 value of 0.0171±0.0070 µM relative to standard thiourea having IC50 value of 4.7455±0.0546 µM. Molecular docking studies suggested that ligands have good binding energy values and bind within the active region of taget protein. Chemo-informatics properties were evaluated by computational approaches and it was found that synthesized compounds mostly obeyed the Lipinski’ rule.
Delayed Birth-Related Femur Fracture after Cesarean Section: A Case Report
Authors: Kanai Yuji , Honda Yoshinobu , Honda Tsuyoshi , Sanpei Minoru
Published: August 2018

Background Birth-related femur fractures are rare. They have been reported following difficult delivery and are commonly diagnosed immediately after birth or on the following day. However, some birth-related femur fractures are diagnosed several days after birth. Mechanisms underlying the development of delayed femur fracture are incompletely understood.

Case We report the case of a girl diagnosed with a left spiral femur fracture with associated edema and hypoesthesia on postpartum day 9. A nondisplacement femur fracture was identified on plain radiography at birth after cesarean section; however, it was undiagnosed due to the lack of symptoms. She was treated with plaster cast fixation; the physical examination at age 1 was normal. Herein, the diagnosis of birth-related femur fracture according to plain radiography findings suggests that the symptoms related to birth trauma develop several days after birth.

Conclusion Birth-related fracture should be considered in all neonatal femur fracture cases and in patients with no symptoms at birth. Neonates delivered in the breech presentation by cesarean section should be carefully monitored after birth. The findings of the present case further our understanding of the pathogenic mechanisms underlying delayed diagnosis of birth-related femur fracture.
Hook Plate for Volar Rim Fractures of the Distal Radius: Review of the First 23 Cases and Focus on Dorsal Radiocarpal Dislocation
Authors: Biondi Marco , Keller Marco , Merenghi Letizia , Gabl Markus , Lauri Giulio
Published: August 2018

Background Fragment-specific fixation of the distal radius is born to fix each articular fragment with limited surgical approach and low-profile devices. Over time, many devices with different designs and characteristics have been developed. However, many of them have showed the inability to securely fix marginal, small, and comminuted fragments as bony ligament avulsions and bony compression injuries.

Purpose The purpose of this study was to evaluate the clinical and radiological outcome of a new device born to treat marginal articular fractures of the distal radius.

Patients and Methods A retrospective review was conducted on 23 patients with a mean follow-up of 21 months including postoperative clinical evaluation, grip strength, computed tomography scan, and X-ray control.

Results All fragments healed and maintained reduced until the final follow-up. The carpus was aligned with the distal radius in all patients presenting with a radiocarpal dislocation.

Conclusion The volar rim fragment is an attachment site for the short radiolunate and the volar distal radioulnar ligament. Its unstable fixation can lead to articular incongruity, volar or dorsal subluxation of the carpus, and distal radioulnar instability. The involvement of this fragment on distal radius fractures is relatively common and many studies of the literature have been focused on its treatment. The Hook Plate stabilizes distal fragments at their bone–ligament interface. In addition to bony reduction, the device permits to stabilize the capsule and ligaments, as volar bony ligament avulsions, in a picture of dorsal radiocarpal dislocation.

Level of Evidence This is a Level IV, case series.
Prognostic Factors for Liver Transplantation in Unresectable Hepatoblastoma
Authors: Cano Esther , Dore Mariela , Jimenez Gomez Javier , Sánchez Galán Alba , Vilanova-Sánchez Alejandra , Andres Ane , Encinas Jose , Martinez Leopoldo , Hernandez Francisco , Lopez Santamaria Manuel , Triana Junco Paloma
Published: August 2018

Aim Hepatoblastoma is the most frequent hepatic tumor in children, and its initial presentation will affect treatment and prognosis. The aim of this study is to evaluate long-term results of liver transplantation in children with unresectable hepatoblastoma.

Patients and Methods This is a retrospective review of patients with hepatoblastoma who underwent liver transplantation, analyzing risk factors, tumor presentation, treatment, and long-term survival to identify prognostic factors.

Results Thirty-one patients underwent liver transplantation in the context of unresectable hepatoblastoma, mainly males (67%) and with risk factors such as prematurity (12.9%), maternal smoking (6.5%), and familial adenomatous polyposis (3.2%). Most frequent presentation was multifocal PRETEXT III (51.6%) and PRETEXT IV (45.2%), with metastasis at diagnosis in 12.9% and vascular involvement in 54.8%.

Twenty-one patients received a living-donor (67.7%) and 10 a cadaveric graft (32.2%), at 31.7 months of age (5–125). Most transplants were primary, and only two were performed as rescue therapy after an attempt of surgical resection of the tumor.

Overall survival 1 and 5 years after transplantation were 93.3% ± 4.6% and 86.4% ± 6.3%, respectively. We could not find any statistically significant differences between risk factors, tumor presentation, type of graft, or type of transplant.

Conclusion Liver transplantation has increased hepatoblastoma survival in unresectable tumors. Probably due to these good results, we have not been able to find significant prognostic factors in this cohort.
Squeezing and resonance in a generalized Caldirola-Kanai type quantum parametric oscillator
Authors: A. Büyükaşık Şirin
Published: August 2018

The evolution operator of a Caldirola-Kanai type quantum parametric oscillator with a generalized quadratic Hamiltonian is obtained using the Wei-Norman Lie algebraic approach, and time evolution of the eigenstates of a harmonic oscillator and Glauber coherent states is found explicitly. Behavior of this oscillator is investigated under the influence of the external mixed term B(t)(q^p^+p^q^)/2, which affects the squeezing properties of the wave packets, and linear terms D0(t)q^,  E0(t)p^ responsible for their displacement in time. According to this, we construct all exact quantum models with different parameters B(t), for which the structure of the Caldirola-Kanai oscillator in position space is preserved. Then, for each model, we obtain explicit solutions and analyze the squeezing and displacement properties of the wave packets according to the frequency modification by B(t) and periodic forces in the corresponding classical equation of motion.
Sub-logistic source can prevent blow-up in the 2D minimal Keller-Segel chemotaxis system
Authors: Xiang Tian
Published: August 2018

It is well known that the Neumann initial-boundary value problem for the minimal Keller-Segel chemotaxis system in a 2D bounded smooth domain has no blow-ups for any presence of logistic source of cell kinetics. Here, for a large class of cell kinetics including sub-logistic sources, we find an explicit condition involving the chemotactic strength, the asymptotic “damping” rate, and the initial mass of cells to ensure the uniform-in-time boundedness for the corresponding 2D Neumann initial-boundary value problem. Our finding in particular shows that sub-logistic source can prevent blow-up in 2D, indicating that logistic damping is not the weakest damping to guarantee boundedness for the 2D Keller-Segel minimal chemotaxis model.
Development of a variable-energy, high-intensity, pulsed-mode ion source for low-energy nuclear astrophysics studies
Authors: Cooper Andrew L. , Kelly K. J. , Machado E. , Pogrebnyak I. , Surbrook J. , Tysor C. , Thompson P. , Emamian M. , Walsh B. , Carlin B. , Dermigny J. R. , Champagne A. E. , Clegg T. B.
Published: August 2018

The primary challenge in directly measuring nuclear reaction rates near stellar energies is their small cross sections. The signal-to-background ratio in these complex experiments can be significantly improved by employing high-current (mA-range) beams and novel detection techniques. Therefore, the electron cyclotron resonance ion source at the Laboratory for Experimental Nuclear Astrophysics underwent a complete upgrade of its acceleration column and microwave system to obtain high-intensity, pulsed proton beams. The new column uses a compression design with O-ring seals for vacuum integrity. Its voltage gradient between electrode sections is produced by the parallel resistance of channels of chilled, deionized water. It also incorporates alternating, transverse magnetic fields for electron suppression and an axially adjustable beam extraction system. Following this upgrade, the operational bremsstrahlung radiation levels and high-voltage stability of the source were vastly improved, over 3.5 mA of target beam current was achieved, and an order-of-magnitude increase in normalized brightness was measured. Beam optics calculations, structural design, and further performance results for this source are presented.
A floating wide-band current source for electrical impedance tomography
Authors: Khalighi M. , Mikaeili M.
Published: August 2018

The quality of reconstructed images in Electrical Impedance Tomography (EIT) depends on two essential factors: first, precision of the EIT hardware in current injection and voltage measurement and second, efficiency of its image reconstruction algorithm. Therefore the current source plays an important and a vital role in EIT instruments. Floating-load current sources constructed using sink and source drivers have better performance and higher output impedance than grounded-load (single-ended) current sources. In addition, a main feature of this kind is that the current source is not connected to the ground potential directly but via a large impedance. In this paper, we first focus on recent studies on designed EIT current sources, and after that, a practical design of a floating-load high output impedance current source—operating over a wide frequency band—will be proposed in detail. Simulation results of the proposed voltage-controlled current source (VCCS), along with some other models, will be shown and compared. At the end, the results of practical tests on the VCCS and a few EIT images, taken using our prototype EIT system coupled with the mentioned VCCS, will be illustrated which proves the quality of the proposed current source.
A 1-m non-resonant inelastic x-ray scattering spectrometer at BL15U, Shanghai Synchrotron Radiation Facility
Authors: Ni Dong-Dong , Kang Xu , Yan Shuai , Huang Xin-Chao , Xiong Tao , Liang Dong-Xu , Yang Ke , Zhu Lin-Fan
Published: August 2018

We report the design, construction, and commissioning of a spectrometer for non-resonant inelastic x-ray scattering study installed at BL15U, Shanghai Synchrotron Radiation Facility. It features a 1-m vertical scattering arm. An energy resolution of 1.3 eV is achieved based on the 1 m Rowland circle and the diced Si(555) crystal analyzer with a fixed Bragg angle of about 88.8°. The inelastic squared form factors of 21S + 21P of helium with respect to the momentum transfer were measured and compared with the accurate and reliable theoretical calculations in order to verify the spectrometer. Furthermore, the spectrometer is designed to work in the momentum transfer region of 0 Å−1 < q < 8.68 Å−1 and to initially focus on the non-resonant inelastic x-ray scattering studies on gaseous samples.