bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation between surface crack width and steel corrosion in reinforced concrete
Authors: Mak Michele Win Tai , Desnerck Pieter , Lees Janet M.
Published: October 2018

Reinforced concrete structures are subjected to weather conditions, chemical attack and other sources of deterioration that can affect their performance. In particular, corrosion of the internal steel reinforcement is considered to be one of the main causes of structural deterioration. A possible consequence of corrosion is cracking of the surrounding concrete. Visual inspections are often used to inform asset management strategies. Finding a relationship between cracks that are visible on the outer surface of a structure and corrosion of the internal reinforcement can be helpful when making assessment decisions. To this end, unconfined cylindrical concrete specimens with an embedded steel bar have been subjected to accelerated corrosion using an impressed current density of 200µA/cm2, leading to steel mass losses between 5-24%. This paper discusses the measured correlation between corrosion-induced surface crack widths and degree of reinforcement corrosion. The tests highlighted some limitations of a set-up that is commonly adopted for accelerated corrosion and concentric pull-out bond testing. The findings of this study represent a first step towards the standardisation of accelerated corrosion testing procedures using an impressed current.
Service life extension of state highway 16 bridges – New Zealand’s first hybrid corrosion protection application
Authors: Christodoulou Christian , Cobbs Ryan , Corbett Paul , Elliot Mike
Published: October 2018

State Highway 16 (SH16) is an existing motorway of significant strategic importance connecting central Auckland to the city's western suburbs and beyond. It carries, on average, some 90,000 vehicles per day, and runs through an environmentally sensitive coastal marine reserve. Two highway bridges, namely Whau River Bridge and Causeway Bridge are currently being refurbished due to extensive chloride contamination as a result of exposure to a tidal marine environment and exhibit surface cracking, spalling and reinforcement corrosion. A hybrid corrosion protection system has been selected as the preferred corrosion management solution to arrest corrosion and to ensure a residual service life of 50 years. The hybrid corrosion protection (HCP) system comprises discrete zinc anodes which were installed on both the reinforced and pre-stressed concrete piles from the Lowest Astronomical Tide (LAT) level, up to the soffit of the crossbeams. The anodes operate in two phases, initially energised using low voltage DC power to arrest ongoing corrosion and thereafter in galvanic mode to provide corrosion prevention for the residual service life. HCP minimised physical works on site, negated the requirement for extensive replacement of chloride contaminated concrete, allowed work to take place accommodating incoming and outgoing tides and offers protection against chloride induced corrosion to the substructures. This is the first HCP system designed and installed in New Zealand, and it is believed to be the first of its kind for pre-stressed concrete in tidal water in the world.
A 5 year track record on a galvanic CP system applied on a light weight concrete bridge with prestressed steel – Developments in time of the effectiveness as determined by depolarisation values and current densities
Authors: van den Hondel A.J. (Hans) , Gulikers Joost , Giorgini Roberto , van den Hondel Anthony (W.M.)
Published: October 2018

This paper gives insight in the research and investigations which were undertaken on a post tensioned light-weight concrete box girder bridge in the Netherlands. This project started in the first half of 2013 and measurements are still executed regularly. Due to long-term leakage of a longitudinal joint between 2 parts of the bridge, chlorides had penetrated into the concrete up to the level of the reinforcement and beyond, causing severe corrosion of the steel, spalling of the concrete cover and eventually causing danger for the shipping underneath the bridge due to falling lumps of concrete. To solve this problem, Galvanic Cathodic Protection (GCP) was applied in 2 stages. Firstly, in 2013, zinc based anode strips were applied on the soffit of 2 post tensioned lightweight bridge segments for the purpose of testing and monitoring. After obtaining good results from the test, in 2014/2015 the remaining 29 bridge segments were repaired and protected with the same GCP system as well. This paper reviews subsequent potential decay and current densities measurements, which have provided valuable information on GCP performance and throwing power. The results of anode performance at different locations and depths are reviewed. Concrete resistivity have shown a major influence on the effectiveness of the installed GCP system.
New Ashton Arch – functional assessment of direct and indirect construction costs and evaluation of service life with respect to flooding risk.
Authors: Ronné Philip , Newmark Abe , du Toit Nadri , van Wijk Heinrich
Published: October 2018

The bridge crossing the Cogmanskloof River in the town of Ashton, South Africa, had a history of over-topping due to severe flood events. The poor flood resilience of the bridge was aggravated by the generally hydraulically inefficient openings, the number of substructure supports in the river course, and a high debris load during flooding. The strategically important tourist route had to be closed, while localized flood damage repairs were undertaken, with resultant adverse effects on the local economy. As part of a road safety improvement project between the towns of Ashton and Montagu, improvement of the flooding resistance at the Ashton river bridge was required. This paper documents the functional evaluation of economicand technical-assessments of the flooding risks for the existing retro-fitted bridge. A new tied-arch bridge was the selected structural form of the replacement structure – based on the assessment of the key service life and constructability criteria. The structural form of the Ashton Arch paid careful regard to the scenic location and historic character of the previous multiple arch bridge form.
A practical methodology to assess corrosion in concrete sewer pipes
Authors: Taheri Shima , Ams Martin , Bustamante Heriberto , Vorreiter Louisa , Withford Michael , Martin Clark Simon
Published: October 2018

The combination of Neutron Tomography (NT), Scanning Electron Microscopy (SEM, with and without elemental analysis), pH profiling and Microindentation Mapping techniques was used to develop a methodology for the assessment of concrete sewer pipe deterioration. We demonstrate a viable method for health monitoring of concrete sewer pipes and the evaluation of competing mitigation strategies.
Health monitoring and repair of a concrete shell roof structure
Authors: Pazhanivel K. , Arunachalam S. , Meenakshisundaram S.
Published: October 2018

A Corrugated doubly curved sea shell form Concrete Structure of 70 mm thickness is functioning for the past 21 years, with good performance in an institutional building entrance hall of size 30m x 30m. The shell having only boundary beam; sloping to one diagonal corner at + 5 m level, the adjacent two opposite diagonal corners at +7 m level and the peak corner is at + 9 m level, supported by columns and footings are resting on rock. The designer has not taken care for thermal resistance performance and not checked for earth quake, and there was no maintenance except periodical cement based whitewash. But, it has performed well in an earthquake of Richter magnitude 4.0 and performing well for the climatic temperature variations ranging from 19◦C to 44◦C during the 21 years of life span. Vertical micro cracks were noticed in the boundary beams. Roof Shell is fixed with the boundary beams. The roof top surface is fixed with weathering ceramic tiles of size 25 mm x 25 mm bonded using tile bond branded chemical adhesive, has opened bonding in a period of five years in the higher deformation area. Hence, the observation was started by performance based health monitoring. Suitable smart materials were applied for surface skin coat to take care of the positive and negative stress-strains and deformations due to temperature variations. The static and dynamic stability against overturning, sliding and gravity forces is ensured adequate. The integral action of the system and the Elastic and Inelastic ductile behaviour of the shell are observed to be higher.
A study on the numerical modelling of UHPFRC-strengthened members
Authors: Franssen Renaud , Guner Serhan , Courard Luc , Mihaylov Boyan
Published: October 2018

The maintenance of large aging infrastructure across the world creates serious technical, environmental, and economic challenges. Ultra-high performance fibre-reinforced concretes (UHPFRC) are a new generation of materials with outstanding mechanical properties as well as very high durability due to their extremely low permeability. These properties open new horizons for the sustainable rehabilitation of aging concrete structures. Since UHPFRC is a young and evolving material, codes are still either lacking or incomplete, with recent design provisions proposed in France, Switzerland, Japan, and Australia. However, engineers and public agencies around the world need resources to study, model, and rehabilitate structures using UHPFRC. As an effort to contribute to the efficient use of this promising material, this paper presents a new numerical modelling approach for UHPFRC-strengthened concrete members. The approach is based on the Diverse Embedment Model within the global framework of the Disturbed Stress Field Model, a smeared rotating-crack formulation for 2D modelling of reinforced concrete structures. This study presents an adapted version of the DEM in order to capture the behaviour of UHPFRC by using a small number of input parameters. The model is validated with tension tests from the literature and is then used to model UHPFRC-strengthened elements. The paper will discuss the formulation of the model and will provide validation studies with various tests of beams, columns and walls from the literature. These studies will demonstrate the effectiveness of the proposed modelling approach.
Use of Strain-Hardening Cement-Based Composites (SHCC) for Retrofitting
Authors: Müller Steffen , Mechtcherine Viktor
Published: October 2018

Strain-hardening cement-based composites (SHCC, or Engineered Cementitious Composites, ECC) were developed in the early 1990th and have been since then an object of numerous investigations which number increases every year. Under tensile loading SHCC exhibit fine and well distributed cracking accompanied by large inelastic deformations prior to reaching ultimate strain capacity. Such behaviour makes SHCC suitable for repair and strengthening. The present article reports on the transfer of SHCC from laboratory tests to a practical application and on monitoring this application over several years. At the laboratory scale, neutron radiography was used to visualize the capillary water suction by a specimen made of a multiple cracked SHCC repair layer and a cracked RC substrate. The obtained results led to a practical implementation on a concrete water reservoir in Germany. The presented project served the purpose of testing the new technology in real scale and investigating challenges arising when laboratory scale is left for a larger one, especially resulting from the real mixing and placement conditions. The application was brought into life by industrial partners under close supervision of the authors. The repair layer is in service for several years now and under observation by the TU Dresden with respect to cracking behaviour and material deterioration.
Characterization of Shear Strength of FRP Anchors
Authors: Mahrenholtz Philipp , Cho Jae-Yeol , Park Ja-Min , Eligehausen Rolf
Published: October 2018

A critical performance aspect of FRP retrofitted concrete elements is the bonding of the FRP sheet to the concrete surface. In general, the performance is limited by the debonding of the loaded FRP sheets from the concrete surface. One method to delay debonding and enhance the capacity is the use of FRP anchors which interlock the FRP sheet to the concrete body. FRP anchors are made of rolled FRP fibres epoxied into in predrilled boreholes. There are a considerable number of studies on FRP strengthening methods available, and also FRP anchors attract more attention of the research community recently. However, to date FRP anchors were tested in a system together with the FRP sheet attached to the concrete, inhibiting the development of general design models. Moreover, the anchor behaviour was never tested for cyclic loads, though most applications are for seismic retrofitting schemes and cyclic shear loading generally results in reduced load capacity due to fatigue failure. To overcome the deficit in knowledge, shear tests on various FRP anchors were carried out. For these tests, FRP anchors were installed in concrete specimens on a separating steel section. The FRP anchor was then directly loaded to determine the capacity of the isolated component. This paper describes the testing approach and procedure. Details on the experimental results for static tests are presented and an outlook on seismic tests is given.
Retrofit and Renovation of Concrete Bridges with Fibre Reinforced Polymer (FRP): The Third Alternative
Authors: Visser Gerrit , Ijselmuijden Kees Van , Klamer Ernst , Zijl Gideon Van
Published: October 2018

This paper presents Fibre Reinforced Polymer (FRP) as a third alternative construction material worth considering when retrofitting a bridge structure. FRP offers the following advantages: lighter than steel and concrete, non-corrosive, low in maintenance, stronger than structural steel and fatigue resistant. FRP has been used in Europe and more specifically in the Netherlands for almost 20 years in the retrofitting of road bridges, in new pedestrian bridges, road bridges and lock doors for sluices. The Netherlands has recently developed the updated Dutch Design Code CUR Recommendation 96, which was published in December 2017. The CUR Recommendation 96 will form the basis for developing the Eurocode FRP which is expected to be published between 2020 and 2025. The use of FRP in retrofitting of bridges is presented using examples which demonstrate how existing concrete decks, and steel and concrete substructures could be retained by the use of FRP in the retrofitting solution. Due to FRP being a relatively unknown material within the South African bridge design field, the authors have embarked on an awareness campaign targeting academics, government bodies, suppliers, manufacturers and contractors, with the aim of presenting FRP as a third alternative construction material in the South African bridge fraternity.
Olifants River Bridge Widening
Authors: Rowan Andrew , Thomson Les
Published: October 2018

The Olifants River Bridge B3611 carries the N11 over the Olifants River, just North of the Loskop Dam. This structure was originally built in 1979 and was recently widened as part of the South African Roads Agency Limited (SANRAL)’s upgrade to the N11. At the time of design, very little was known about the bridge as no ‘As Built' drawings were available. Due to the remote locality of the structure, exploratory investigations were reserved until the construction phase. The final design solution was therefore amended during the construction phase in order to account for the reinforcement found within the structure. In addition to the heavier dead weight of the new widened deck, the bridge would be required to carry higher loads under modern loading codes. Widening works included new widened cantilevers with new reinforced concrete balustrades, tying into existing reinforcement. Strengthening for bending was provided to the main deck beams by means of longitudinal FRP plates epoxied to the soffit. Transverse pierhead strengthening using DYWIDAG bars was installed to counter increased moments, and pier strengthening using a reinforced concrete jacket was implemented to strengthen the piers. Durability concrete was specified in accordance with current SANRAL regulations and the durability performance of the concrete, even in this remote location was excellent. This paper summarises the work that was completed as part of this project.
On the effect of the physical structure of cement on shrinkage of cementitious materials
Authors: Karimi Hossein , Yu Qingliang , Brouwers H.J.H.
Published: October 2018

The physical structure of cement is of pivotal importance in the study of volumetric stability and cracking of concrete. While most of efforts in the category of crack mitigation of concrete have been devoted to the incorporation of sophisticated chemical admixtures into concrete mixtures, less attention has been paid to the fact that the modification of cement structure can be considered as a sustainable solution to this problem. This study aims to investigate the effect of the modification of the physical structure of cement on workability, early-age strength and autogenous shrinkage of cement pastes. The results show that the modification of cement physical structure can be used as a sustainable route to reduce shrinkage of cementitious materials.
A review of Waste Tyre Rubber as an Alternative Concrete Consituent Material
Authors: Mushunje Kudzai , Otieno Mike , Ballim Yunus
Published: October 2018

The current global waste tyre generation far exceeds its consumption in terms of recycling and re-use. The traditional recycling and re-use methods like thermal incineration have proven ineffective, costly and in some cases environmentally unsustainable. Particularly, in developing countries where some of the sophisticated techniques required to process tyres to allow them to be utilised are either too costly or have not yet been developed. The situation has resulted in accumulation of large waste tyre stockpiles that pose health and safety risks. To combat the problem, the use of waste tyre rubber in concrete construction has been proposed. Several studies have been conducted to assess the effects of the inclusion of waste tyre rubber in its different forms (fibres, particles), for concrete production and the results are promising. Although there are some apparent demerits to the inclusion of tyre rubber in concrete, the potential benefits seem to overshadow the negatives. This paper reviews published research on the scientific and technical viability of using waste tyre rubber in concrete production. It discusses the production and properties of waste tyre particles. It highlights advances made with regards to the incorporation of tyre rubber material in concrete, focusing on the engineering properties of the tyre rubber modified concrete. In conclusion, recommendations for future research and possible application for the material will be discussed.
A parametric building energy simulation case study on the potential and limitations of passive design in the Mediterranean climate of Malta
Authors: Manz Heinrich , Micallef Daniel , Borg Simon Paul , Buhagiar Vincent
Published: October 2018

The present case study sets out to investigate the potential and limitations of passive building design in a typical Mediterranean climate. The Maltese Islands were taken as the case study location. Assuming a fully detached, cuboid-shaped, generic multi-storey office building, one representative storey was modelled by means of the building energy simulation code WUFI®Plus. Thermal comfort was analysed based on the adaptive acceptable operative room temperature concept of EN 15251 for buildings without mechanical cooling systems. Assuming neither artificial heating nor cooling, the free-running operative room temperature was evaluated. By means of a parametric study, the robustness of the concept was analysed and the impact of orientation, window to wall area ratio, glazing, shading, thermal insulation, nighttime ventilation and thermal mass on the achievable level of thermal comfort is shown and discussed. It is concluded that in a well-designed building and by means of decent insulation (present case: Uwall = 0.54 W/(m2 · K)), double glazing, variable external shading devices and passive cooling by nighttime ventilation, a high level of thermal comfort is achievable in this climate using only very minor amounts of energy for artificial heating and cooling or possibly even none at all.
Therapieanpassungen mithilfe von Trendpfeilen bei kontinuierlichen Glukosemonitoring (CGM)-Systemen
Authors: Ziegler Ralph , Siegmund Thorsten , von Sengbusch Simone , Kroeger Jens , Schubert Oliver , Werkmeister Petra , Deiss Dorothee
Published: October 2018

Die unterschiedlichen Systeme zum kontinuierlichen interstitiellen Glukosemonitoring nutzen Trendpfeile, mit denen dem Anwender in grafischer Form eine Prognose zum künftigen Glukoseverlauf angezeigt wird. Sie werden sowohl beim Glukosemonitoring mit „Real-Time“-Alarmen als auch beim Glukosemonitoring mit intermittierendem Scannen genutzt. Die Trendpfeile sind für viele Menschen mit Diabetes eine wichtige Grundlage für Stoffwechselkorrekturen, weshalb ihre Interpretation zur Voraussetzung für adäquate Therapieentscheidungen wird. Ziel dieser Publikation ist es, auf der Grundlage verfügbarer Vorschläge zur Trendpfeilinterpretation eine allgemein gültige Handlungsanweisung für Diabetesteams und Nutzer von kontinuierlichem Glukosemonitoring mit der Möglichkeit der notwendigen individuellen Anpassung zu geben.
Aktuelle Pränataldiagnostik: ein Überblick
Authors: Fornoff Friderike
Published: October 2018

Neue Erkenntnisse im Bereich der medizinischen Forschung führen auch in der Pränataldiagnostik zu immer mehr Möglichkeiten. Mehr Wissen über das Ungeborene kann zur Gesundheit von Kind und Mutter beitragen. Aber nicht immer. Gelingt es nicht, das Wissen richtig zu deuten, so führt mehr Wissen zu mehr Unsicherheit. Dies kann eine Schwangerschaft nachhaltig belasten oder zu unnötigen Interventionen bei Mutter und Kind führen. Pränataldiagnostik ist daher sowohl fachlich als auch ethisch hoch komplex. Wer Paare in der Schwangerschaft betreut und berät, sollte die nachfolgend vorgestellten pränataldiagnostischen Verfahren kennen, einordnen und erklären können.
Die Attraktivität von Geburtshäusern als Arbeitsplatz
Authors: Krupp Ramona
Published: October 2018

Geburtshäusern und Hebammenpraxen mangelt es an Nachwuchskräften. Junge Hebammen zu gewinnen, gestaltet sich zunehmend als Herausforderung. Wie attraktiv ist das Geburtshaus als Arbeitsplatz? Und wie lassen sich Berufseinsteigerinnen für diese Arbeit begeistern? Diesen Fragen geht die vorliegende Studie nach. In Kooperation mit dem Geburtshaus Bonn entwickelte die Autorin eine standardisierte Umfrage, um die Zufriedenheit der Geburtshaus-Hebammen mit ihrem Arbeitsplatz zu untersuchen, potenzielle Einflussfaktoren zu ermitteln und Handlungsempfehlungen für die Zukunft abzuleiten.
Internistische Onkologie
Authors: Zschäbitz Stefanie , Jäger Dirk
Published: October 2018

Auf dem diesjährigen ASCO wurden einige Studien präsentiert, die zu Leitlinienänderungen führen werden. Erfreulicherweise können durch positive
Nicht-Unterlegenheitsstudien die Behandlungsstrategien für manche unserer Patienten zukünftig schonender ausfallen. Wir möchten im Folgenden für die
wesentlichen Tumorentitäten die klinisch relevanten Präsentationen zusammenfassen.
Psychische Belastung bei unbegleiteten jungen Geflüchteten in Jugendhilfeeinrichtungen
Authors: Sierau Susan , Schneider Esther , Nesterko Yuriy , von Klitzing Kai , Glaesmer Heide
Published: October 2018

Ziel der Studie Häufigkeiten psychischer Auffälligkeiten bei unbegleiteten Geflüchteten erfassen.

Methodik Soziodemografie und psychische Belastung wurden in der Selbst- und Fremdbeurteilung an 105 Jugendlichen erhoben.

Ergebnisse Am häufigsten waren Auffälligkeiten in den Bereichen Depression (42 %), Verhalten (35 %) und posttraumatische Belastungsstörung (32 %). Die Jugendlichen berichteten mehr Probleme mit Gleichaltrigen, die Betreuer mehr Probleme der Jugendlichen in den Bereichen Emotion, Verhalten und Hyperaktivität.

Schlussfolgerung Die Daten verdeutlichen den psychologischen Hilfebedarf dieser Gruppe.
Invited Article: Distributed analysis of nonlinear wave mixing in fiber due to forward Brillouin scattering and Kerr effects
Authors: London Yosef , Diamandi Hilel Hagai , Bashan Gil , Zadok Avi
Published: October 2018

Forward stimulated Brillouin scattering (F-SBS) is a third-order nonlinear-optical mechanism that couples between two co-propagating optical fields and a guided acoustic mode in a common medium. F-SBS gives rise to nonlinear wave mixing along optical fibers, which adds up with four-wave mixing induced by the Kerr effect. In this work, we report the distributed mapping of nonlinear wave mixing processes involving both mechanisms along standard single-mode fiber, in analysis, simulation, and experiment. Measurements are based on a multi-tone, optical time-domain reflectometry setup, which is highly frequency-selective. The results show that F-SBS leads to nonlinear wave mixing processes that are more complex than those that are driven by the Kerr effect alone. The dynamics are strongly dependent on the exact frequency detuning between optical field components. When the detuning is chosen near an F-SBS resonance, the process becomes asymmetric. Power is coupled from an upper-frequency input pump wave to a lower-frequency one, and the amplification of Stokes-wave sidebands is more pronounced than that of anti-Stokes-wave sidebands. The results are applicable to a new class of distributed fiber-optic sensors, based on F-SBS.
Geometric instability catalyzes mitochondrial fission
Authors: Irajizad Ehsan , Ramachandran Rajesh , Agrawal Ashutosh
Published: October 2018

The mitochondrial membrane undergoes extreme remodeling during fission. While a few membrane-squeezing proteins are recognized as the key drivers of fission, there is a growing body of evidence that strongly suggests that conical lipids play a critical role in regulating mitochondrial morphology and fission. However, the mechanisms by which proteins and lipids cooperate to execute fission have not been quantitatively investigated. Here, we computationally model the squeezing of the largely tubular mitochondrion and show that proteins and conical lipids can act synergistically to trigger buckling instability and achieve extreme constriction. More remarkably, the study reveals that the conical lipids can act with different fission proteins to induce hierarchical instabilities and create increasingly narrow and stable constrictions. We reason that this geometric plasticity imparts significant robustness to the fission reaction by arresting the elastic tendency of the membrane to rebound during protein polymerization and depolymerization cycles. Our in vitro study validates protein–lipid cooperativity in constricting membrane tubules. Overall, our work presents a general mechanism for achieving drastic topological remodeling in cellular membranes.
Comprehensive analysis of formin localization inXenopusepithelial cells
Authors: Higashi Tomohito , Stephenson Rachel E. , Miller Ann L.
Published: October 2018

Reorganization of the actin cytoskeleton is crucial for cellular processes, including cytokinesis and cell–cell junction remodeling. Formins are conserved processive actin-polymerizing machines that regulate actin dynamics by nucleating, elongating, and bundling linear actin filaments. Because the formin family is large, with at least 15 members in vertebrates, there have not been any comprehensive studies examining formin localization and function within a common cell type. Here, we characterized the localization of all 15 formins in epithelial cells of Xenopus laevis gastrula-stage embryos. Dia1 and Dia2 localized to tight junctions, while Fhod1 and Fhod3 localized to adherens junctions. Only Dia3 strongly localized at the cytokinetic contractile ring. The Diaphanous inhibitory domain–dimerization domain (DID-DD) region of Dia1 was sufficient for Dia1 localization, and overexpression of a Dia1 DID-DD fragment competitively removed Dia1 and Dia2 from cell–cell junctions. In Dia1 DID-DD–overexpressing cells, Dia1 and Dia2 were mislocalized to the contractile ring, and cells exhibited increased cytokinesis failure. This work provides a comprehensive analysis of the localization of all 15 vertebrate formins in epithelial cells and suggests that misregulated formin localization results in epithelial cytokinesis failure.
Identifying Effective Behavior Change Techniques for Alcohol and Illicit Substance Use During Pregnancy: A Systematic Review
Authors: Fergie Libby , Campbell Katarzyna A , Coleman-Haynes Tom , Ussher Michael , Cooper Sue , Coleman Tim
Published: October 2018

Background

During pregnancy, consuming alcohol and using illicit drugs can have serious health implications for both mother and child. Behavioral change interventions, especially those underpinned by theoretical constructs, can be effective in reducing harmful substance use among pregnant women.

Purpose

To understand what type of behavior change mechanisms could be useful in reducing alcohol consumption or achieving abstinence from illicit drug use during pregnancy, this review aimed to identify behavior change techniques (BCTs), the smallest, active components of interventions that may be effective. It also aimed to establish the extent that psychosocial-based theories were used to inform intervention design.

Methods

To identify eligible randomized controlled trials (RCTs), five databases were searched electronically from the end search dates of the most recent Cochrane systematic reviews on behavioral interventions for each behavior, until March 2018. Within the RCTs, intervention descriptions were analyzed for BCT content and extent of theory use in the intervention design process and outcome measurements, in each trial, was established. “Effectiveness percentages,” the number of times a BCT had been a component of an effective intervention divided by the total number of interventions it had been used in, were calculated for BCTs used in two or more trials.

Results

Including all RCTs from the Cochrane reviews, and those published subsequently, nine alcohol and six illicit drug trials were identified. Interventions tested in four alcohol RCTs and no illicit drugs RCTs showed positive results. Subsequent data were extracted for alcohol consumption trials only. Thirteen BCTs showed “potential effectiveness” for alcohol consumption. Six of nine included alcohol trials reported using theory but not extensively.

Conclusions

Action planning, behavioral contract, prompts/cues, self-talk, offer/direct toward written material, problem solving, feedback on behavior, social support (unspecified), information about health consequences, behavior substitution, assess current readiness and ability to reduce excess alcohol consumption, goal setting (behavior), and tailor interactions appropriately are BCTs that could be useful in helping reduce alcohol consumption among pregnant women.
Understanding the Evolution of Antibiotic-nonsusceptible Pneumococcal Nasopharyngeal Colonization Following Pneumococcal Conjugate Vaccine Implementation in Young Children
Authors: Danino Dana , Givon-Lavi Noga , Ben-Shimol Shalom , Greenberg David , Dagan Ron
Published: October 2018

Background

Four main processes determine pneumococcal conjugate vaccine (PCV) antibiotic-nonsusceptible Streptococcus pneumoniae (ANSP) carriage: reduction of PCV serotypes, increase of non-PCV serotypes, potential overall reduction in carriage, and within-serotype nonsusceptibility resulting from continuous antibiotic pressure. The post-PCV implementation dynamics of these components were examined in young children from 2 distinct ethnic populations: Jewish and Bedouin.

Methods

We performed ongoing, prospective, population-based, active surveillance initiated at the time of 7- and 13-valent PCVs (PCV7; PCV13) implementation. Nasopharyngeal cultures for S. pneumoniae were obtained daily from children aged <5 years who visited the only pediatric emergency room in the district during a 6-year period (2009 to 2015).

Results

Of 8446 nasopharyngeal samples, 48.3% were positive (42.0% and 52.8% for Jewish and Bedouin children, respectively; P < .001). Nonsusceptibility was significantly more frequent among PCV serotypes than among non-PCV serotypes and among Bedouin children than among Jewish children. PCV serotype carriage declined by 80%, while that of non-PCV serotypes increased by 140%. The overall (all serotypes) pneumococcal carriage significantly declined (33% and 11% in Bedouin and Jewish children, respectively). Among non-PCV isolates, the proportion of ANSP significantly increased with time in both populations. As a summation of all 4 processes, ANSP carriage significantly decreased among both Bedouin and Jewish children.

Conclusions

PCV impact on ANSP nasopharyngeal carriage is a dynamic, multicomponent process, highly dependent on antibiotic consumption in the community, which may result in a continuous increase in antibiotic resistance in the replacing serotypes.
Optimizing state change detection in functional temporal networks through dynamic community detection
Authors: Vaiana Michael , Goldberg Ethan M , Muldoon Sarah F
Published: October 2018

Dynamic community detection provides a coherent description of network clusters over time, allowing one to track the growth and death of communities as the network evolves. However, modularity maximization, a popular method for performing multilayer community detection, requires the specification of an appropriate null network as well as resolution and interlayer coupling parameters. Importantly, the ability of the algorithm to accurately detect community evolution is dependent on the choice of these parameters. In functional temporal networks, where evolving communities reflect changing functional relationships between network nodes, it is especially important that the detected communities reflect any state changes of the system. Here, we present analytical work suggesting that a uniform null network provides improved sensitivity to the detection of small evolving communities in temporal networks with positive edge weights bounded above by 1, such as certain types of correlation networks. We then propose a method for increasing the sensitivity of modularity maximization to state changes in nodal dynamics by modelling self-identity links between layers based on the self-similarity of the network nodes between layers. This method is more appropriate for functional temporal networks from both a modelling and mathematical perspective, as it incorporates the dynamic nature of network nodes. We motivate our method based on applications in neuroscience where network nodes represent neurons and functional edges represent similarity of firing patterns in time. We show that in simulated data sets of neuronal spike trains, updating interlayer links based on the firing properties of the neurons provides superior community detection of evolving network structure when groups of neurons change their firing properties over time. Finally, we apply our method to experimental calcium imaging data that monitors the spiking activity of hundreds of neurons to track the evolution of neuronal communities during a state change from the awake to anaesthetized state.
Unpacking the ‘black box’ of lay health worker processes in a US-based intervention
Authors: Burke Nancy J , Phung Kristine , Yu Filmer , Wong Ching , Le Khanh , Nguyen Isabel , Nguyen Long , Guan Alice , Nguyen Tung T , Tsoh Janice Y
Published: October 2018

Prior studies have supported the effectiveness of the use of Lay Health Workers (LHWs) as an intervention model for managing chronic health conditions, yet few have documented the mechanisms that underlie the effectiveness of the interventions. This study provides a first look into how LHWs delivered a family-based intervention and the challenges encountered. We utilize observation data from LHW-led educational sessions delivered as part of a randomized controlled trial (RCT) designed to test a LHW outreach family-based intervention to promote smoking cessation among Vietnamese American smokers. The RCT included experimental (smoking cessation) and control (healthy living) arms. Vietnamese LHWs were trained to provide health information in Vietnamese to groups of family dyads (smoker and family member). Bilingual, bicultural research team members conducted unobtrusive observations in a subset of LHW educational sessions and described the setting, process and activities in structured fieldnotes. Two team members coded each fieldnote following a grounded theory approach. We utilized Atlas.ti qualitative software to organize coding and facilitate combined analysis. Findings offer a detailed look at the ‘black box’ of how LHWs work with their participants to deliver health messages. LHWs utilized multiple relational strategies, including preparing an environment that enables relationship building, using recognized teaching methods to engage learners and co-learners as well as using humor and employing culturally specific strategies such as hierarchical forms of address to create trust. Future research will assess the effectiveness of LHW techniques, thus enhancing the potential of LHW interventions to promote health among underserved populations.
Hunt for the tipping point during endocrine resistance process in breast cancer by dynamic network biomarkers
Authors: Liu Rui , Wang Jinzeng , Ukai Masao , Sewon Ki , Chen Pei , Suzuki Yutaka , Wang Haiyun , Aihara Kazuyuki , Okada-Hatakeyama Mariko , Chen Luonan
Published: October 2018

Acquired drug resistance is the major reason why patients fail to respond to cancer therapies. It is a challenging task to determine the tipping point of endocrine resistance and detect the associated molecules. Derived from new systems biology theory, the dynamic network biomarker (DNB) method is designed to quantitatively identify the tipping point of a drastic system transition and can theoretically identify DNB genes that play key roles in acquiring drug resistance. We analyzed time-course mRNA sequence data generated from the tamoxifen-treated estrogen receptor (ER)-positive MCF-7 cell line, and identified the tipping point of endocrine resistance with its leading molecules. The results show that there is interplay between gene mutations and DNB genes, in which the accumulated mutations eventually affect the DNB genes that subsequently cause the change of transcriptional landscape, enabling full-blown drug resistance. Survival analyses based on clinical datasets validated that the DNB genes were associated with the poor survival of breast cancer patients. The results provided the detection for the pre-resistance state or early signs of endocrine resistance. Our predictive method may greatly benefit the scheduling of treatments for complex diseases in which patients are exposed to considerably different drugs and may become drug resistant.
Factors Affecting Prognosis of Patients With Osteoblastoma of the Mobile Spine: A Long-Term Follow-up Study of 70 Patients in a Single Center
Authors: Jia Qi , Liu Chao , Yang Jian , Yin Huabin , Zhao Jian , Wei Haifeng , Liu Tielong , Yang Xinghai , Yang Cheng , Zhou Zhenhua , Xiao Jianru
Published: October 2018

BACKGROUND

Osteoblastoma (OBL) in the mobile spine is a benign tumor with aggressive potential. There is not much published information on OBL of the mobile spine as a result of rarity of the disease. There are controversies over the aggressive subtype and prognostic factors of the condition.

OBJECTIVE

To explore the aggressive subtype and investigate prognostic factors of OBLs in the mobile spine.

METHODS

A retrospective analysis of spinal OBL was performed by survival analysis. Patients in 2 cohorts were analyzed based on the Enneking grade and pathological evaluation. Local recurrence-free survival (RFS) was estimated using the Kaplan–Meier method to identify potential prognostic factors. Factors with P ≤ .05 were subjected to multivariate analysis by Cox regression analysis. P ≤ .05 were considered statistically significant.

RESULTS

Included in this study were 70 patients with spinal OBL who were followed up by a mean of 67.1 mo (range 24-188). Local recurrence was detected in 9 cases after initial surgery, and death occurred in 2 cases. The result of statistical analysis suggested that Epithelioid OBL (EO) with Enneking stage 3 (St.3) and total spondylectomy were independent prognostic factors for RFS.

CONCLUSION

St.3 or EO lesions seem to be more aggressive than St.2 or conventional osteoblastomas, but St.3 and EO should be considered simultaneously in predicting the aggressiveness of the lesion and the risk of recurrence. Total spondylectomy performed either by en bloc or piecemeal could significantly reduce recurrence of OBLs in the mobile spine.
Phenotype and target-based chemical biology investigations in cancers
Authors: Chen Guo-Qiang , Xu Ying , Shen Shao-Ming , Zhang Jian
Published: October 2018

Chemical biology has been attracting a lot of attention because of the key roles of chemical methods and techniques in helping to decipher and manipulate biological systems. Although chemical biology encompasses a broad field, this review will focus on chemical biology aimed at using exogenous chemical probes to interrogate, modify and manipulate biological processes, at the cellular and organismal levels, in a highly controlled and dynamic manner. In this area, many advances have been achieved for cancer biology and therapeutics, from target identification and validation based on active anticancer compounds (forward approaches) to discoveries of anticancer molecules based on some important targets including protein-protein interaction (reverse approaches). Herein we attempt to summarize some recent progresses mainly from China through applying chemical biology approaches to explore molecular mechanisms of carcinogenesis. Additionally, we also outline several new strategies for chemistry to probe cellular activities such as proximity-dependent labeling methods for identifying protein-protein interactions, genetically encoded sensors, and light activating or repressing gene expression system.
Ceftolozane-Tazobactam for the Treatment of Multidrug-Resistant Pseudomonas aeruginosa Infections: A Multicenter Study
Authors: Gallagher Jason C , Satlin Michael J , Elabor Abdulrahman , Saraiya Nidhi , McCreary Erin K , Molnar Esther , El-Beyrouty Claudine , Jones Bruce M , Dixit Deepali , Heil Emily L , Claeys Kimberly C , Hiles Jon , Vyas Nikunj M , Bland Christopher M , Suh Jin , Biason Kenneth , McCoy Dorothy , King Madeline A , Richards Lynette , Harrington Nicole , Guo Yi , Chaudhry Saira , Lu Xiaoning , Yu Daohai
Published: October 2018

Background

Multidrug-resistant Pseudomonas aeruginosa infections remain common in hospitals worldwide. We investigated the outcomes associated with the use of ceftolozane-tazobactam for the treatment of these infections.

Methods

Data were collected retrospectively from 20 hospitals across the United States about adults who received ceftolozane-tazobactam for the treatment of multidrug-resistant P aeruginosa infections of any source for at least 24 hours. The primary outcome was a composite of 30-day and inpatient mortality, and secondary outcomes were clinical success and microbiological cure. Multivariable regression analysis was conducted to determine factors associated with outcomes.

Results

Two-hundred five patients were included in the study. Severe illness and high degrees of comorbidity were common, with median Acute Physiology and Chronic Health Evaluation (APACHE) II scores of 19 (interquartile range [IQR], 11–24) and median Charlson Comorbidity Indexes of 4 (IQR, 3–6). Delayed initiation of ceftolozane-tazobactam was common with therapy started a median of 9 days after culture collection. Fifty-nine percent of patients had pneumonia. On susceptibility testing, 125 of 139 (89.9%) isolates were susceptible to ceftolozane-tazobactam. Mortality occurred in 39 patients (19%); clinical success and microbiological cure were 151 (73.7%) and 145 (70.7%), respectively. On multivariable regression analysis, starting ceftolozane-tazobactam within 4 days of culture collection was associated with survival (adjusted odds ratio [OR], 5.55; 95% confidence interval [CI], 2.14–14.40), clinical success (adjusted OR, 2.93; 95% CI, 1.40–6.10), and microbiological cure (adjusted OR, 2.59; 95% CI, 1.24–5.38).

Conclusions

Ceftolozane-tazobactam appeared to be effective in the treatment of multidrug-resistant P aeruginosa infections, particularly when initiated early after the onset of infection.
Cyber-Routines, Political Attitudes, and Exposure to Violence-Advocating Online Extremism
Authors: Hawdon James , Bernatzky Colin , Costello Matthew
Published: October 2018

The Internet’s relatively unfettered transmission of information risks exposing individuals to extremist content. Using online survey data (N = 768) of American youth and young adults, we examine factors that bring individuals into contact with online material advocating violence. Combining aspects of social structure-social learning theory with insights from routine activity theory, we find that exposure to violence-advocating materials is positively correlated with online behaviors, including the use of social media platforms and the virtual spaces individuals frequent. Target antagonism is also correlated with exposure to violence-advocating materials, but guardianship and online and offline associations are not. Finally, feelings of dissatisfaction with major social institutions and economic disengagement are associated with exposure to violent materials online.
Comparing survival outcomes in early stage desmoplastic melanoma with or without adjuvant radiation
Authors: Abbott Jamie L. , Qureshi Muhammad M. , Truong Minh T. , Sahni Debjani
Published: October 2018

Desmoplastic melanoma (DM) due to its rare and locally aggressive nature, can be difficult to study and to treat effectively. Whether the optimal treatment approach for these tumors should include adjuvant radiation has been unclear in the literature. In this retrospective study of the National Cancer Database, 2390 patients with localized DM were included for analysis. 2082 were treated with wide local excision (WLE) and 308 were treated with wide local excision and adjuvant radiation therapy (WLE + RT). Overall survival (OS) in these groups was compared on crude and adjusted analyses utilizing Cox proportional hazards regression modeling. There was no difference in OS at 1, 3, and 5 years on initial analysis. Subsequent multivariate analysis and propensity score analysis showed a survival benefit in those treated with WLE + RT. Multivariate analysis demonstrated significantly decreased OS in cases of residual tumor following surgical excision. Adjuvant radiation was more likely to be performed for tumors on the head and neck, tumors with higher pathologic American Joint Committee on Cancer stage and T classifications, and tumors with positive surgical margins. This is the first study to demonstrate significantly improved OS in early-stage DM patients treated with WLE + RT compared to WLE alone.