bluuebunny/crossref_metadata_2025 huggingface dataset:
Profile of Sustainability in Additive Manufacturing and Environmental Assessment of a Novel Stereolithography Process
Authors: Malshe Harsha , Nagarajan Hari , Pan Yayue , Haapala Karl
Published: September 2015

Additive manufacturing has emerged as an arena that is receiving intense interest from numerous technology domains, traditional and non-traditional manufacturers. With this growing interest, concerns have arisen regarding the relative performance of these novel processes compared to conventional techniques from economic, environmental, and social perspectives. Sustainability-related benefits can be realized through additive manufacturing, and it is often promoted as a sustainable technology. For appropriate future development and application, however, it will be important to understand relative costs, environmental impacts, and human health effects of processes and materials. Prior research addressing sustainability and additive manufacturing is briefly reviewed. A life cycle assessment is then conducted to understand the environmental performance of a novel additive manufacturing process known as fast mask-image-projection based stereolithography (Fast MIP-SL). In Fast MIP-SL, projection light is patterned by a digital micromirror device as a mask image to selectively cure liquid photopolymer resin, and a two-way movement design is adopted to quickly recoat material. The cradle-to-gate life cycle assessment considers the impacts related to the curing of one resin type and the consumption of electricity in the production of parts of various geometries. Using the ReCiPe 2008 method (hierarchist weighting), it is found that damage to resource availability dominates ecosystems and human health damage types for each part assessed.
Graphene Oxide Colloidal Suspensions as Cutting Fluids for Micromachining: Part 1 — Fabrication and Performance Evaluation
Authors: Chu Bryan , Singh Eklavya , Samuel Johnson , Koratkar Nikhil
Published: September 2015

This paper is aimed at investigating the effects of graphene oxide platelet (GOP) geometry (i.e., lateral size and thickness) and oxygen functionalization on the cooling and lubrication performance of GOP colloidal suspensions. The techniques of thermal reduction and ultrasonic exfoliation were used to manufacture three different types of GOPs. For each of these three types of GOPs, colloidal solutions with GOP concentrations varying between 0.1–1 wt% were evaluated for their dynamic viscosity, thermal conductivity and micromachining performance. The ultrasonically-exfoliated GOPs (with 2–3 graphene layers and lowest in-solution characteristic lateral length of 120 nm) appear to be the most favorable for micromachining applications. Even at the lowest concentration of 0.1 wt%, they are capable of providing a 51% reduction in the cutting temperature and a 25% reduction in the surface roughness value over that of the baseline semi-synthetic cutting fluid. For the thermally-reduced GOPs (with 4–8 graphene layers and in-solution characteristic lateral length of 562–2780 nm), a concentration of 0.2 wt% appears to be optimal. The findings suggest that the differences seen between the colloidal suspensions in terms of their droplet spreading, evaporation and the subsequent GOP film-formation characteristics may be better indicators of their machining performance, as opposed to their bulk fluid properties.
Wire-Fed Additive Manufacturing of Transparent Glass Parts
Authors: Luo Junjie , Gilbert Luke , Qu Chuang , Wilson Jacob , Bristow Douglas , Landers Robert , Kinzel Edward
Published: September 2015

This paper presents a new technique for additive manufacturing of transparent glass. In this process, transparent glass is wire-fed into a laser generated melt pool, which solidifies as the work piece is moved relative to a stationary laser beam. The key parameters are identified in terms of their effects on the morphology and transparency of printed walls. The relationship between these parameters is studied experimentally. It is demonstrated that the process parameters strongly affect the morphology and proper selection of the scan speed, feed rate and laser power can produce optimum results. A key advantage of this process relative to powder bed techniques is the ability to form optically transparent parts. The process parameters also determine the transmissivity of the final sample. The transmissivity is measured experimentally for builds with different process parameters.
Sensor-Based Online Process Fault Detection in Additive Manufacturing
Authors: Rao Prahalad K. , Liu Jia (Peter) , Roberson David , Kong Zhenyu (James)
Published: September 2015

The objective of this work is to identify failure modes and detect the onset of process anomalies in Additive Manufacturing (AM) processes, specifically focusing on Fused Filament Fabrication (FFF). We accomplish this objective using advanced Bayesian non-parametric analysis of in situ heterogeneous sensor data. The proposed method can ultimately lead to intelligent decision making and closed loop control in AM processes. Experiments are conducted on a desktop FFF machine (MakerBot Replicator 2X) instrumented with a heterogeneous sensor array including thermocouples, accelerometers, an infrared temperature sensor, and a real-time miniature video borescope. FFF process failures are detected online using the non-parametric Bayesian Dirichlet Process (DP) mixture model and evidence theory based on the experimentally acquired sensor data. This sensor data-driven defect detection approach facilitates real-time identification and correction of FFF process drifts with an accuracy and precision approaching 85% (average F-score). In comparison, the F-score from existing approaches, such as Probabilistic Neural Networks, Naïve Bayesian Clustering, Support Vector Machines, and Quadratic Discriminant Analysis was in the range of 55% to 75%.
Feasibility Analysis of Using Local Remanufactured Products: A Case Study of Industrial Starters and Alternators
Authors: Wang Steve Hsueh-Ming , Williams Teresa J.
Published: September 2015

Reported by the U.S. International Trade Commission, production of remanufactured goods had a total annual amount of approximately $43 billion and accounted for about 2% of total manufacturing annual sales from 2009–2011. The remanufacturing industry of motor vehicle parts was the third largest of the remanufacturing sectors and had a production of remanufactured goods with an annual total of approximately $6.2 billion in 2011. Reliable replacement engine parts for heavy duty equipment in Alaska are a high need. Remanufactured engine parts are one way to fulfill that need. While remanufactured industrial starters and alternators are available in Alaska they are currently remanufactured out of state and shipped to a local Anchorage, Alaska business to be sold. The purpose of this paper is to determine what the best method of obtaining industrial starters and alternators is. To that end a variety of forecasting analysis is performed using data from an Anchorage, Alaska business. The results indicate that while remanufacturing industrial starters and alternators in Anchorage, Alaska is possible, there are some problems such as core availability and employee utilization that need to be overcome in order to make it a viable option.
Role of Tool Flank Wear and Machining Speed in Developing of Residual Stress in Machined Surface During High Speed Machining of Titanium Alloys
Authors: Zhang Xueping , Shivpuri Rajiv , Srivastava Anil K.
Published: September 2015

Residual stresses generated from finish machining have a significant impact on the fatigue life of mechanical components by controlling crack initiation and propagation processes in their near subsurface. As governing variables, tool geometry, tool wear, machining parameter, work material property, and lubrication conditions have been widely studied to determine their effects on residual stress pattern in machined surface and subsurface. Among those parameters, tool flank wear was seldom fully investigated although tool flank wear, as well as machining speed, has been identified as the most important contributor to residual stress. Especially, tool flank wear becomes more significant due to the poor work thermal property during the high speed machining of titanium Ti-6Al-4V alloy. This study aims to investigate the combined role of tool flank wear and machining speed in developing residual stress in the machining of titanium alloy using finite element method. A microstructure sensitive material model based on Self Consistent Method (SCM) is adopted to incorporate the phase state and its transformations during machining cycle. Critical flank wear land and corresponding machining speeds are identified, beyond which compressive residual stresses are transferred into tensile residual stresses. High machining speeds demonstrate a distinct influence on residual stresses by means of promoting tool flank wear rate. The numerical simulation results are validated by empirical data provided in previous research.
Investigation on the Effect of Carbon Nanotubes Concentration on the Electrical and Rheological Properties of PP/MWCNTs Composites
Authors: Stan Felicia , Sandu Laurentiu , Fetecau Catalin
Published: September 2015

The objective of this paper was to investigate the electrical and rheological behaviors of polypropylene (PP) filled with 1.0, 3.0 and 5.0 wt.-% multi-wall carbon nanotubes (MWCNTs). The flow behavior was analyzed in terms of the melt flow index measured at temperatures relevant for the injection molding process and the flow activation energy was calculated using an Arrhenius type equation. The electrical behavior of PP/MWCNTs composites was examined by DC resistance measurements on injection molded samples.

The experimental results have shown that the incorporation of MWCNTs effectively enhances the electrical conductivity of the injection molded PP/MWCNTs composites. The composites under analysis can be classified as semi-conductors with the conducting network arranged in 4 dimensions, i.e. the critical exponent of the power-law dependence of the conductivity on the wt.-% MWCNTs is 2.37. The increased conductivity is explained by the orientation of the MWCNTs along the melt flow and the increased nanotubes-to-nanotubes contact after the formation of the percolation network.
Feasibility of End Mill Cooling Using the Venturi Effect With Compressed Air
Authors: Ruszkiewicz Brandt J. , Reese Zachary C. , Roth John T.
Published: September 2015

In many machining applications tool wear is a major problem. Cutting edges on tools wear out with repeated use leading to their inevitable failure. This tool failure causes a poor surface finish on the work piece being cut. Currently cutting fluid is applied during the cutting process to extend the life of a tool and is effective. Cutting fluid is considered a hazardous material which causes problems during disposal. Disposal of hazardous waste can be expensive causing a push to find alternate green cooling methods. This paper focuses on the feasibility of using the venturi effect on compressed air to replace water based cutting fluids. The two processes are to be compared on the grounds of cooling of the tool and work piece as well as chip removal. Cooling comparisons will be made through the examination of a straight channel cut, and chip removal will be gauged by how large of a mass the air streams can move. It was found that, in these areas, an accelerated stream of compressed air through the correct diameter nozzle outperforms the liquid cutting fluid in both aspects during end milling operations. These findings lead the authors to believe that in the future compressed air, or other pressurized gas, will be the most economical and effective green cooling technique.
Fundamental Requirements for Data Representations in Laser-Based Powder Bed Fusion
Authors: Feng Shaw C. , Witherell Paul W. , Ameta Gaurav , Kim Duck Bong
Published: September 2015

Additive Manufacturing (AM) processes intertwine aspects of many different engineering-related disciplines, such as material metrology, design, in-situ and off-line measurements, and controls. Due to the increasing complexity of AM systems and processes, data cannot be shared among heterogeneous systems because of a lack of a common vocabulary and data interoperability methods. This paper aims to address insufficiencies in laser-based Powder Bed Fusion (PBF), a specific AM process, data representations to improve data management and reuse in PBF. Our approach is to formally decompose the processes and align PBF process-specifics with information elements as fundamental requirements for representing process-related data. The paper defines the organization and flow of process information. After modeling selected PBF processes and sub-processes as activities, we discuss requirements for the development of more advanced process data models that provide common terminology and process knowledge for managing data from various stages in AM.
Design, Fabrication, Simulation and Testing of a Novel Ocean Wave Energy Converter
Authors: Liang Changwei , Ai Junxiao , Zuo Lei
Published: September 2015

The total useful wave resource around the world is estimated to be larger than 2 TW. Harvesting a small portion of the available wave energy resource could contribute significantly to meet the urgent energy demand. Therefore, a lot of wave energy converters have been developed in the past decades. Traditionally, air turbine, hydroelectric motor and linear electromagnetic motor are used in wave energy converters as the power takeoff system. Although these power takeoffs have their own advantages, power takeoffs are still recognized as the most important challenge in ocean wave energy technology. In this paper, a mechanical motion rectifier (MMR) based power takeoff system is proposed and prototyped for wave energy converter. This power takeoff system can convert the bi-directional wave motion into unidirectional rotation of the generator by integrating two one-way clutches into a rack pinion system. A 500W prototype which contains a heaving buoy and MMR-based power takeoff system was designed and fabricated. The models of power takeoff system and the corresponding single-buoy wave energy converter are built and analyzed. Lab testing of power takeoff mechanism and ocean testing of the overall ocean wave converter system are also conducted.
A Hybrid Surface Processing Method Using Surface Alloying and Pulsed Laser Micro Melting on S7 Tool Steel
Authors: Morrow Justin D. , Wang Qinghua , Duffie Neil A. , Pfefferkorn Frank E.
Published: September 2015

A hybrid surface treatment method is presented on S7 tool steel by alloying the surface layer with boron and following with pulsed laser micro polishing (PLuP). The objective of the hybrid approach is twofold: First, surface alloying changes the properties of the surface layer that are relevant to the PLuP process (e.g. liquid metal density, viscosity, and surface tension). This allows more control over the laser polishing phenomena for better smoothing. Second, surface alloying and laser melting/quenching is proposed as a novel method of creating amorphous surface coatings. In this work, boron was introduced into the surface of an S7 tool steel sample using pack cementation. This sample was then ground on a bias to create a flat surface with a gradient in chemical composition and this surface was laser melted. The effect of this variation in alloy chemistry on the surface features created by pulsed laser melting is presented.
Nanoindentation Models With Realistic AFM Tip Geometries
Authors: Promyoo Rapeepan , El-Mounayri Hazim , Varahramyan Kody
Published: September 2015

In this paper, a three-dimensional computational model for Atomic Force Microscopy (AFM) based nanoindentation processes is being developed. Molecular Dynamics (MD) and Finite Element (FE) techniques are used to model and simulate mechanical indentation at the nanoscale. The correlation between the indentation conditions, including applied force and tip radius, and defect mechanism in substrate is investigated. The tip geometries used in the model are the same as those used in the experiments. The MD simulations of nanoindentation process are performed on different crystal orientations of single-crystal gold substrate, Au(100), Au(110), and Au(111). In MD simulation, the material deformation is extracted from the final locations of atoms, which are displaced by the rigid indenter. The simulation also allows for the prediction of forces at the interface between the indenter and substrate. In addition to the modeling, an AFM is used to conduct actual indentation at the nanoscale, and provide measurements to which the simulation predictions are compared.
Corrosion Study on Liquid Marble Based Localized Electrochemical Deposition on Cold Rolled Steel
Authors: Shailendar Shiv , Sundaram Murali M.
Published: September 2015

Application of electrochemical methods for micro repair is being researched. A liquid marble is a liquid droplet coated with hydrophobic micro or nano powders. When the liquid used is a suitable electrolyte, it can be used for localized electrochemical deposition (LECD) which is in turn used for micro repair. Though the feasibility of this process is already established, the properties of the deposit with respect to the metal substrate has to be studied. Corrosion is an important property that can vary between two metals. An immersion corrosion test is performed on a substrates having micro spots made using LECD using 5% NaCl for 240 hours. The results are compared with specimens of the same dimension which underwent the same corrosion testing process. It was found that the micro deposits did not affect the corrosion rate significantly and therefore localized electro deposition using liquid marbles may be considered as a potential method for micro repair.
Acoustic analysis of the frequency-dependent coupling between the frog's ears
Authors: Shofner William P.
Published: September 2015

The ears of anurans are coupled through the Eustachian tubes and mouth cavity. The degree of coupling varies with frequency showing a bandpass characteristic, but the characteristics differ between empirically measured data based on auditory nerve responses and tympanic membrane vibration. In the present study, the coupling was modeled acoustically as a tube connected with a side branch. This tube corresponds to the Eustachian tubes, whereas the side branch corresponds to the mouth cavity and nares. The analysis accounts for the frequency dependency shown by the empirical data and reconciles the differences observed between the coupling as measured by tympanic membrane vibration and auditory nerve responses.
Early hominin auditory capacities
Authors: Quam Rolf , Martínez Ignacio , Rosa Manuel , Bonmatí Alejandro , Lorenzo Carlos , de Ruiter Darryl J. , Moggi-Cecchi Jacopo , Conde Valverde Mercedes , Jarabo Pilar , Menter Colin G. , Thackeray J. Francis , Arsuaga Juan Luis
Published: September 2015

Hearing in early hominins may have facilitated an increased emphasis on short-range vocal communication in open habitats.
Writing in the granular gel medium
Authors: Bhattacharjee Tapomoy , Zehnder Steven M. , Rowe Kyle G. , Jain Suhani , Nixon Ryan M. , Sawyer W. Gregory , Angelini Thomas E.
Published: September 2015

The reversible fluid-solid transition in granular gels enables the three-dimensional writing of soft, delicate, macroscopic structures with microscopic detail.
In Vitro
Culture of Previously Uncultured Oral Bacterial Phylotypes
Authors: Thompson Hayley , Rybalka Alexandra , Moazzez Rebecca , Dewhirst Floyd E. , Wade William G.
Published: September 2015

Around a third of oral bacteria cannot be grown using conventional bacteriological culture media. Community profiling targeting 16S rRNA and shotgun metagenomics methods have proved valuable in revealing the complexity of the oral bacterial community. Studies investigating the role of oral bacteria in health and disease require phenotypic characterizations that are possible only with live cultures. The aim of this study was to develop novel culture media and use an
in vitro
biofilm model to culture previously uncultured oral bacteria. Subgingival plaque samples collected from subjects with periodontitis were cultured on complex mucin-containing agar plates supplemented with proteose peptone (PPA), beef extract (BEA), or Gelysate (GA) as well as on fastidious anaerobe agar plus 5% horse blood (FAA).
In vitro
biofilms inoculated with the subgingival plaque samples and proteose peptone broth (PPB) as the growth medium were established using the Calgary biofilm device. Specific PCR primers were designed and validated for the previously uncultivated oral taxa
Bacteroidetes
bacteria HOT 365 and HOT 281,
Lachnospiraceae
bacteria HOT 100 and HOT 500, and
Clostridiales
bacterium HOT 093. All agar media were able to support the growth of 10 reference strains of oral bacteria. One previously uncultivated phylotype,
Actinomyces
sp. HOT 525, was cultivated on FAA. Of 93 previously uncultivated phylotypes found in the inocula, 26 were detected in
in vitro
-cultivated biofilms.
Lachnospiraceae
bacterium HOT 500 was successfully cultured from biofilm material harvested from PPA plates in coculture with
Parvimonas micra
or
Veillonella dispar
/
parvula
after colony hybridization-directed enrichment. The establishment of
in vitro
biofilms from oral inocula enables the cultivation of previously uncultured oral bacteria and provides source material for isolation in coculture.
The ABCs of Candida albicans Multidrug Transporter Cdr1
Authors: Prasad Rajendra , Banerjee Atanu , Khandelwal Nitesh Kumar , Dhamgaye Sanjiveeni
Published: September 2015

In the light of multidrug resistance (MDR) among pathogenic microbes and cancer cells, membrane transporters have gained profound clinical significance. Chemotherapeutic failure, by far, has been attributed mainly to the robust and diverse array of these proteins, which are omnipresent in every stratum of the living world.
Candida albicans
, one of the major fungal pathogens affecting immunocompromised patients, also develops MDR during the course of chemotherapy. The pivotal membrane transporters that
C. albicans
has exploited as one of the strategies to develop MDR belongs to either the ATP binding cassette (ABC) or the major facilitator superfamily (MFS) class of proteins. The ABC transporter
Candida
drug resistance 1 protein (Cdr1p) is a major player among these transporters that enables the pathogen to outplay the battery of antifungals encountered by it. The promiscuous Cdr1 protein fulfills the quintessential need of a model to study molecular mechanisms of multidrug transporter regulation and structure-function analyses of asymmetric ABC transporters. In this review, we cover the highlights of two decades of research on Cdr1p that has provided a platform to study its structure-function relationships and regulatory circuitry for a better understanding of MDR not only in yeast but also in other organisms.
Complete Genome Sequence of Pseudomonas aeruginosa Phage vB_PaeM_CEB_DP1
Authors: Pires Diana P. , Sillankorva Sanna , Kropinski Andrew M. , Lu Timothy K. , Azeredo Joana
Published: September 2015

vB_PaeM_CEB_DP1 is a
Pseudomonas aeruginosa
bacteriophage (phage) belonging to the
Pbunalikevirus
genus of the
Myoviridae
family of phages. It was isolated from hospital sewage. vB_PaeM_CEB_DP1 is a double-stranded DNA (dsDNA) phage, with a genome of 66,158 bp, containing 89 predicted open reading frames.
Draft Genome Sequence of
Bacillus
sp. FJAT-27238 for Setting up Phylogenomic Analysis of Genomic Taxonomy of
Bacillus
-Like Bacteria
Authors: Liu Guo-hong , Liu Bo , Wang Jie-ping , Che Jian-Mei , Chen Qian-Qian , Zhu Yu-Jing
Published: September 2015

Bacillus
sp. FJAT-27238 is a Gram-positive, spore-forming, and aerobic bacterium. Here, we report the draft genome sequence of
Bacillus
sp. FJAT-27238, with 6,134,829 bp, which will provide useful information for setting up phylogenomic analysis of the genomic taxonomy of
Bacillus
-like bacteria as well as for the functional gene mining and application of strain FJAT-27238. The genomic DNA G+C content was 47.37%.
Draft Genome Sequence and Gene Annotation ofStemphylium lycopersiciStrain CIDEFI-216
Authors: Franco Mario E. E. , López Silvina , Medina Rocio , Saparrat Mario C. N. , Balatti Pedro
Published: September 2015

Stemphylium lycopersiciis a plant-pathogenic fungus that is widely distributed throughout the world. In tomatoes, it is one of the etiological agents of gray leaf spot disease. Here, we report the first draft genome sequence ofS. lycopersici, including its gene structure and functional annotation.
Draft Genome Sequence of Acetobacterium bakii DSM 8239, a Potential Psychrophilic Chemical Producer through Syngas Fermentation
Authors: Hwang Soonkyu , Song Yoseb , Cho Byung-Kwan
Published: September 2015

Acetobacterium bakii
DSM 8239 is an anaerobic, psychrophilic, and chemolithoautotrophic bacterium that is a potential platform for producing commodity chemicals from syngas fermentation. We report here the draft genome sequence of
A. bakii
DSM 8239 (4.14 Mb) to elucidate its physiological and metabolic properties related to syngas fermentation.
The association between maternal perceptions of own weight status and weight status of her child: results from a national cohort study
Authors: Dowd Kieran P , Kirwan Robert P , Hannigan Ailish , Purtill Helen , O'Gorman Clodagh S
Published: September 2015

Objectives

To examine the relationship between maternal self-reported and measured height and weight, maternal perceived weight status and measured body mass index (BMI), and maternal perceived child weight status and measured child BMI.

Setting and design

Population-representative National Longitudinal Study of Children Growing Up in Ireland.

Methods

Height and weight of 7655 mothers and their 9-year-old children were objectively measured using standard measurement techniques. Mothers’ perceptions of their own weight status and the weight status of their child were reported. The association between accurate perceptions of the mother for herself and her child was tested.

Results

Mothers overestimated their height by a mean of 0.5 cm (SD=2.9), underestimated their weight by a mean of 1.4 kg (SD=3.8), consequently underestimating their BMI by a mean of 0.6 kg/m2(SD=1.7). The majority (60%) of obese mothers correctly categorised their own weight status. Only 17% of mothers of obese children correctly categorised the weight status of their child. Overweight/obese mothers who correctly categorised their own weight status were more likely to correctly categorise their overweight/obese child compared with those who incorrectly categorised their own weight status (44% vs 23%, 95% CI for difference 13% to 28%, p<0.001 for girls; 37% vs 27%, 95% CI 2% to 18%, p=0.02 for boys; significantly greater difference for girls compared with boys, p=0.04).

Conclusions

Maternal perceptions of their own weight status tend to be more accurate than maternal perceptions of their overweight or obese child. Overweight/obese mothers who correctly categorised their own weight status were more likely to correctly categorise their overweight/obese child.
Acute appendicitis within an obturator hernia
Authors: Mitchell David Edmund , Yunaev Michael
Published: September 2015

We present the case of a 17-year-old girl who presented with the signs and symptoms of acute appendicitis; however, during laparoscopic surgery, it was found that the appendix had herniated through the obturator canal. This pathology has previously been associated with an unfavourable outcome and has been reported, in the literature, in older, emaciated women.
Solitary spinal epidural cavernous haemangiomas as a rare cause of myelopathy
Authors: Meng Ying , Shamji Mohammed F
Published: September 2015

Cavernous haemangiomas rarely occur in the spinal epidural space. We report the case of a 27-year-old man who presented with myelopathy secondary to spinal cord compression from a purely epidural lesion. The imaging characteristics of cavernous haemangiomas are unique, reflecting a highly vascular lesion. Key differentiating features from intracranial or intramedullary lesions include the lack of a surrounding hemosiderin ring and popcorn appearance. An urgent referral to a neurosurgeon is recommended given the possibility of acute neurological deterioration from intralesional haemorrhage, and good recovery from early surgical resection. Preoperative planning with thorough patient counselling and availability of matched blood is important, and an en bloc resection approach should be taken to minimise blood loss. In this case, the patient experienced complete recovery after surgical resection. No recurrence after complete resection has been reported in the literature. This suggests a good long-term outcome for the patient and that no early adjuvant therapy is necessary.
Bridging gaps to promote networked care between teams and groups in health delivery systems: a systematic review of non-health literature
Authors: Braithwaite Jeffrey
Published: September 2015

Objectives

To assess non-health literature, identify key strategies in promoting more networked teams and groups, apply external ideas to healthcare, and build a model based on these strategies.

Design

A systematic review of the literature outside of healthcare.

Method

Searches guided by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) of ABI/INFORM Global, CINAHL, IBSS, MEDLINE and Psychinfo databases following a mind-mapping exercise generating key terms centred on the core construct of gaps across organisational social structures that uncovered 842 empirical articles of which 116 met the inclusion criteria. Data extraction and content analysis via data mining techniques were performed on these articles.

Results

The research involved subjects in 40 countries, with 32 studies enrolling participants in multiple countries. There were 40 studies conducted wholly or partly in the USA, 46 wholly or partly in continental Europe, 29 wholly or partly in Asia and 12 wholly or partly in Russia or Russian federated countries. Methods employed included 30 mixed or triangulated social science study designs, 39 qualitative studies, 13 experimental studies and 34 questionnaire-based studies, where the latter was mostly to gather data for social network analyses. Four recurring factors underpin a model for promoting networked behaviours and fortifying cross-group cooperation: appreciating the characteristics andnature of gapsbetween groups; using the leverage ofboundary-spannersto bridge two or more groups; applying various mechanisms to stimulateinteractive relationships; and mobilising those who can exert positiveexternal influencesto promote connections while minimising the impact of those who exacerbate divides.

Conclusions

The literature assessed is rich and varied. An evidence-oriented model and strategies for promoting more networked systems are now available for application to healthcare. While caution needs to be exercised in translating outside ideas and studies, drawing on non-health ideas is useful in providing insights into other sectors.
Preadmission glucocorticoid use and anastomotic leakage after colon and rectal cancer resections: a Danish cohort study
Authors: Ostenfeld Eva Bjerre , Erichsen Rune , Baron John A , Thorlacius-Ussing Ole , Iversen Lene Hjerrild , Riis Anders H , Sørensen Henrik Toft
Published: September 2015

Objective

To examine whether preadmission glucocorticoid use increases the risk of anastomotic leakage after colon and rectal cancer resections.

Design

A population-based cohort study.

Setting

Denmark (2001–2011).

Participants

We identified patients who had undergone a primary anastomosis after a colorectal cancer resection by linking medical registries. Participants who filled their most recent glucocorticoid prescription ≤90, 91–365 and >365 days before their surgery date were categorised as current, recent and former users, respectively.

Main outcome measures

We calculated 30-day absolute risk of anastomotic leakage and computed ORs using logistic regression models with adjustment for potential confounders.

Results

Of the 18 190 patients with colon cancer, anastomotic leakage occurred in 1184 (6.5%). Glucocorticoid use overall was not associated with an increased risk of leakage (6.4% vs 6.9% among never-users; OR 1.05; 95% CI 0.89 to 1.23). Categories of oral, inhaled or intestinal-acting glucocorticoids did not greatly affect risk of leakage. Anastomotic leakage occurred in 695 (13.2%) of 5284 patients with rectal cancer. Glucocorticoid use overall slightly increased risk of leakage (14.6% vs 12.8% among never-users; OR 1.36, 95% CI 1.08 to 1.72). Results did not differ significantly within glucocorticoid categories.

Conclusions

Preadmission glucocorticoids modestly increased the risk of anastomotic leakage mainly after rectal cancer resection. However, absolute risk differences were small and the clinical impact of glucocorticoid use may therefore be limited.
Global, regional and national consumption of major food groups in 1990 and 2010: a systematic analysis including 266 country-specific nutrition surveys worldwide
Authors: Micha Renata , Khatibzadeh Shahab , Shi Peilin , Andrews Kathryn G , Engell Rebecca E , Mozaffarian Dariush
Published: September 2015

Objective

To quantify global intakes of key foods related to non-communicable diseases in adults by region (n=21), country (n=187), age and sex, in 1990 and 2010.

Design

We searched and obtained individual-level intake data in 16 age/sex groups worldwide from 266 surveys across 113 countries. We combined these data with food balance sheets available in all nations and years. A hierarchical Bayesian model estimated mean food intake and associated uncertainty for each age-sex-country-year stratum, accounting for differences in intakes versus availability, survey methods and representativeness, and sampling and modelling uncertainty.

Setting/population

Global adult population, by age, sex, country and time.

Results

In 2010, global fruit intake was 81.3 g/day (95% uncertainty interval 78.9–83.7), with country-specific intakes ranging from 19.2–325.1 g/day; in only 2 countries (representing 0.4% of the world's population), mean intakes met recommended targets of ≥300 g/day. Country-specific vegetable intake ranged from 34.6–493.1 g/day (global mean=208.8 g/day); corresponding values for nuts/seeds were 0.2–152.7 g/day (8.9 g/day); for whole grains, 1.3–334.3 g/day (38.4 g/day); for seafood, 6.0–87.6 g/day (27.9 g/day); for red meats, 3.0–124.2 g/day (41.8 g/day); and for processed meats, 2.5–66.1 g/day (13.7 g/day). Mean national intakes met recommended targets in countries representing 0.4% of the global population for vegetables (≥400 g/day); 9.6% for nuts/seeds (≥4 (28.35 g) servings/week); 7.6% for whole grains (≥2.5 (50 g) servings/day); 4.4% for seafood (≥3.5 (100 g) servings/week); 20.3% for red meats (≤1 (100 g) serving/week); and 38.5% for processed meats (≤1 (50 g) serving/week). Intakes of healthful foods were generally higher and of less healthful foods generally lower at older ages. Intakes were generally similar by sex. Vegetable, seafood and processed meat intakes were stable over time; fruits, nuts/seeds and red meat, increased; and whole grains, decreased.

Conclusions

These global dietary data by nation, age and sex identify key challenges and opportunities for optimising diets, informing policies and priorities for improving global health.
Comparison of health outcomes between hospitalised and non-hospitalised persons with minor injuries sustained in a road traffic crash in Australia: a prospective cohort study
Authors: Gopinath Bamini , Jagnoor Jagnoor , Harris Ian A , Nicholas Michael , Maher Christopher G , Casey Petrina , Blyth Fiona , Sindhusake Doungkamol , Cameron Ian D
Published: September 2015

Objectives

This prospective cohort study aimed to investigate whether there are differences in health outcomes among persons with mild or moderate injuries who were hospitalised compared with those not hospitalised following a road traffic crash.

Setting

Sydney Metropolitan, New South Wales, Australia.

Participants

Persons aged ≥18 years involved in a motor vehicle crash were surveyed at baseline (n=364), and at 12 (n=284) and 24 months (n=252). A telephone-administered questionnaire obtained information on a range of socioeconomic, and preinjury and postinjury psychological and heath characteristics of all participants.

Primary outcome measure

Participants who reported admission to hospital for 24 h or more (but less than 7 days) after the crash were classified as being hospitalised; those admitted for less than 24 h were classified as non-hospitalised.

Results

Around 1 in 5 participants (19.0%) were hospitalised for ≥24 h after the crash. After adjusting for age and sex, hospitalised participants compared with those not hospitalised had approximately 2.6 units (p=0.01) lower Short Form-12 Physical Component Summary (SF-12 PCS) scores (poorer physical well-being) and approximately 4.9 units lower European Quality of Life visual analogue scale (EQ-VAS) scores (p=0.05), 12 months later. After further adjusting for education level, whiplash, fracture and injury severity score, participants who were hospitalised had approximately 3.3 units lower SF-12 PCS (p=0.04), 12 months later. The association with EQ-VAS did not persist after multivariable adjustment. No significant differences were observed between the 2 groups in health outcomes at 24-month follow-up.

Conclusions

These findings indicate that long-term health status is unlikely to be influenced by hospitalisation status after sustaining a mild/moderate injury in a vehicle-related crash.
The impact of the environment on patient experiences of hospital admissions in palliative care
Authors: Robinson Jackie , Gott Merryn , Gardiner Clare , Ingleton Christine
Published: September 2015

Objective

To explore the impact of environment on experiences of hospitalisation from the perspective of patient's with palliative care needs.

Methods

A qualitative study design using longitudinal semistructured, face-to-face interviews were used to elicit the views of patients with palliative care needs admitted to hospital in 1 large urban acute hospital in New Zealand. The sample comprised of 14 patients admitted to hospital between July 2013 and March 2014 who met one of the Gold Standard Framework Prognostic Indicators for palliative care need.

Results

Almost all participants described a range of factors associated with the environment which impacted negatively on their experiences of hospitalisation. This included challenges with the physical surroundings, the impact on social relationships with other patients, families and health professionals and the influence of the cultural milieu of the hospital setting.

Conclusions

Emulating the ‘ideal’ environment for palliative care such as that provided in a hospice setting is an unrealistic goal for acute hospitals. Paying attention to the things that can be changed, such as enabling family to stay and improving the flexibility of the physical environment while improving the social interplay between patients and health professionals, may be a more realistic approach than replicating the hospice environment in order to reduce the burden of hospitalisations for patients with palliative care needs.
Reproductive health knowledge, attitudes and practices of adolescents attending an obstetric unit in Georgetown, Guyana
Authors: Rose Elizabeth M , Rajasingam Daghni , Derkenne Ruth C , Mitchell Vivienne , Ramlall Anita A
Published: September 2015

Background

Teenage pregnancy continues to be a serious maternal health issue globally. Problems faced by teenage mothers are biological, social, and psychological, and may include sexual coercion and violence. This study sought to explore formally the knowledge, attitudes and practices of pregnant teenagers in Georgetown, Guyana, which has one of the highest rates of teenage pregnancy in Latin America and the Caribbean.

Methods

This was a cross-sectional, prospective study. After ethical approval had been granted, 50 pregnant girls attending Georgetown Public Hospital Corporation (GPHC) were interviewed during a 6-week period. Using a convenience sample approach, the principal investigator used a questionnaire to collect data. This was then analysed using Stata/SE V.9.2 and Microsoft Excel programs.

Findings

As well as overall poor sexual and reproductive health knowledge and high-risk sexual health practices, our study revealed a high rate of rape and sexual coercion among the 50 girls interviewed. Almost a quarter (22%) admitted to having been raped in the past, and 80% stated a lack of power in their sexual relationships.

Conclusions

There is a need for more targeted sexual and reproductive health services for teenagers attending GPHC, and for more research into sexual violence among this group of women. The establishment of a screening and referral system for those at risk should begin to address specific issues and optimise health outcomes for the women and their babies.
Different risk factors for poor outcome between patients with positive and negative susceptibility vessel sign
Authors: Yan Shenqiang , Liu Keqin , Tong Lusha , Yu Yannan , Zhang Sheng , Lou Min
Published: September 2015

Purpose

The absence of the susceptibility vessel sign (negative SVS) on gradient-recalled echo or susceptibility-weighted imaging (SWI) in thrombolytic therapy has not been well studied. Since positive and negative SVS may have different components, we aimed to investigate the difference in risk factors for clinical outcome between patients with positive and negative SVS.

Methods

We retrospectively examined clinical and imaging data from 85 consecutive patients with acute ischemic stroke with middle cerebral artery occlusion who underwent SWI before intravenous thrombolysis (IVT). We then examined the predictors of negative SVS and the risk factors for a poor outcome (defined as modified Rankin Scale score ≥3) 3 months after IVT in subgroup analysis.

Results

Multivariate regression analysis indicated that previous antiplatelet use (OR 0.076; 95% CI 0.007 to 0.847; p=0.036) and shorter time from onset to treatment (OR 1.051; 95% CI 1.003 to 1.102; p=0.037) were inversely associated with poor outcome in patients with negative SVS, while higher baseline National Institutes of Health Stroke Scale (NIHSS) score was associated with poor outcome in patients with positive SVS (OR 1.222; 95% CI 1.084 to 1.377; p=0.001).

Conclusions

The risk factors for clinical outcome after IVT in patients with negative SVS may differ from those with positive SVS.
A Batch Scheduling Problem with Two Agents
Authors: Choi Byung-Cheon , Park Myoung-Ju
Published: September 2015

In this paper, we consider a two-agent batch scheduling problem on a single machine such that the processing times of agent 1 and the due date of agent 2 in the same batch are identical. The objective is to minimize the total completion time of agent 1 with a constraint on the maximum tardiness of agent 2. First, we propose the optimality conditions. Then, we show that the problem is strongly NP-hard. Finally, we prove the problem remains NP-hard even for the case with one batch of agent 2, and develop a pseudo-polynomial algorithm and an approximation algorithm for this case.
A Hybrid Reliability-Based Design Optimization Approach with Adaptive Chaos Control Using Kriging Model
Authors: Li Gang , Meng Zeng , Hao Peng , Hu Hao
Published: September 2015

Traditional reliability-based design optimization (RBDO) approaches are computationally expensive for complicated problems. To cope with this challenge, a surrogate-based hybrid RBDO approach for the problems with highly nonlinear constraints and multiple local optima is proposed in this study. Specifically, the adaptive chaos control (ACC) method is used to ensure the robustness of the most probable target point (MPTP) search process, and the particle swarm optimization (PSO) algorithm is utilized to conquer the barrier caused by multiple local optima. Three illustrative benchmark examples together with a 3 m diameter orthogrid stiffened shell for current launch vehicles are employed to demonstrate the efficiency and robustness of the proposed method.
Prions: What Are They Good For?
Authors: Si Kausik
Published: September 2015

Prions, a self-templating amyloidogenic state of normal cellular proteins such as PrP, have been identified as the basis of a number of disease states, particularly diseases of the nervous system. This finding has led to the notion that protein aggregation, namely prionogenic aggregates and amyloids, is primarily harmful for the organism. However, identification of proteins in a prion-like state that are not harmful and may even be beneficial has begun to change this perception. This review discusses when and how a prion-based protein conformational switch may be utilized to generate a sustained physiological change in response to a transient stimulus.
Mechanotransduction's Impact on Animal Development, Evolution, and Tumorigenesis
Authors: Fernandez-Sanchez Maria-Elena , Brunet Thibaut , Röper Jens-Christian , Farge Emmanuel
Published: September 2015

Mechanotransduction translates mechanical signals into biochemical signals. It is based on the soft-matter properties of biomolecules or membranes that deform in response to mechanical loads to trigger activation of biochemical reactions. The study of mechanotransductive processes in cell-structure organization has been initiated in vitro in many biological contexts, such as examining cells' response to substrate rigidity increases associated with tumor fibrosis and to blood flow pressure. In vivo, the study of mechanotransduction in regulating physiological processes has focused primarily on the context of embryogenesis, with an increasing number of examples demonstrating its importance for both differentiation and morphogenesis. The conservation across species of mechanical induction in early embryonic patterning now suggests that major animal transitions, such as mesoderm emergence, may have been based on mechanotransduction pathways. In adult animal tissues, permanent stiffness and tissue growth pressure contribute to tumorigenesis and appear to reactivate such conserved embryonic mechanosensitive pathways.
Universal Access to Electricity: Closing the Affordability Gap
Authors: Mitra Subarna , Buluswar Shashi
Published: September 2015

Access to electricity changes lives but only when people can afford electricity-powered services to meet their basic needs, and this is more than just two light bulbs and a fan. Decentralized renewable energy (RE) minigrids, particularly solar photovoltaic (PV) minigrids, can cost-effectively electrify a large share of currently unelectrified rural populations. But the cost of using appliances with this electricity is still much higher than what the poor can afford without deep subsidies. This affordability gap stunts the sustainability and growth of RE minigrids. Significant improvements in the economics of supplying electricity with minigrids, combined with higher-efficiency appliances, are needed to reduce the effective cost of using electricity in decentralized RE minigrids. These would bridge the affordability gap and improve business opportunities and value to users, investors, and service providers and thus create market-driven expansion to overcome the acute lack of funding that they currently face. Technology breakthroughs that can help in this respect include (a) significantly cheaper solar PV components to reduce up-front costs of solar PV minigrids; (b) significantly more affordable and energy-efficient appliances; (c) better-performing bulk storage at a significantly lower cost; (d) affordable and easy-to-use grid management solutions, and (e) a utility in a box for a simpler, cheaper, and faster way to set up minigrids.