bluuebunny/crossref_metadata_2025 huggingface dataset:
Acute‐on‐Chronic Liver Failure: Getting Ready for Prime Time?
Authors: Bajaj Jasmohan S. , Moreau Richard , Kamath Patrick S , Vargas Hugo E. , Arroyo Vicente , Reddy K. Rajender , Szabo Gyongyi , Tandon Puneeta , Olson Jody , Karvellas Constantine , Gustot Thierry , Lai Jennifer C. , Wong Florence
Published: April 2018

Acute on chronic liver failure (ACLF) is the culmination of chronic liver disease and extrahepatic organ failures, which is associated with a high short‐term mortality and immense health care expenditure. There are varying definitions for organ failures and ACLF in Europe, North America, and Asia. These differing definitions need to be reconciled to enhance progress in the field. The pathogenesis of ACLF is multifactorial and related to interactions between the immunoinflammatory system, microbiota, and the various precipitating factors. Individual organ failures related to the kidney, brain, lungs, and circulation have cumulative adverse effects on mortality and are often complicated or precipitated by infections. Strategies to prevent and rapidly treat these organ failures are paramount in improving survival. With the aging population and paucity of organs for liver transplant, the prognosis of ACLF patients is poor, highlighting the need for novel therapeutic strategies. The role of liver transplant in ACLF is evolving and needs further investigation across large consortia. A role for early palliative care and management of frailty as approaches to alleviate disease burden and improve patient‐reported outcomes is being increasingly recognized.

Conclusion: ACLF is a clinically relevant syndrome that is epidemic worldwide and requires a dedicated multinational approach focused on prognostication and management; investigations are underway worldwide to prepare ACLF for prime time. (Hepatology 2018; 00:000‐000)
Five years of health promoting work with bottle shops on the Central Coast of NSW Australia. How can we best ensure outlets check ID?
Authors: Bauer Lyndon , Smith Jeff , Kajons Nicole , Tutt Doug
Published: April 2018

Issue Addressed

Australian surveys indicate that a large proportion of packaged liquor outlets do not check identification for young people before selling alcohol to them. There are a substantial number of presentations to Emergency Departments from young people aged 15 to 17 years. This subgroup is second only to those aged 18 to 24 years. In the 15‐ to 17‐year‐old age group, supply from direct purchase or underage friends, who have purchased alcohol, represents substantial sources of alcohol that is more likely to be consumed without parental supervision.

Method

Teenagers 18‐19 years of age approached a randomly selected sample of bottle shops, on the NSW Central Coast Region, to attempt to purchase alcohol without producing identification (ID). Legally we are unable to test with teens under the age of 18. If outlets do not check ID for customers 18 or 19 years of age, we propose they might not check identification for 15‐ to 17‐year‐olds. A raft of local interventions was employed over four‐survey periods to attempt to reduce selling rates.

Results

The lowest alcohol sales without ID occurred in 2015 when NSW Liquor and Gaming successfully prosecuted a Central Coast outlet for an underage sale. The rate of alcohol sales without checking ID each year was as follows: 2012–43.8%, 2014–37.55%, 2015–21.5% and 2016–45%.

Conclusion

Alcohol sales to young customers without checking ID are common, widespread and seemingly resistant to nonpunitive interventions. The NSW Liquor Act could be modified to allow compliance testing and much more practical enforcement. While Central Coast bottle shops have a better record than other Australian areas showing some improvements with our nonpunitive industry education interventions, the results need to improve substantially to stifle primary supply.
Psychometric properties of the MHC‐SF: An integration of the existing measurement approaches
Authors: Rogoza Radosław , Truong Thi Khanh Ha , Różycka‐Tran Joanna , Piotrowski Jarosław , Żemojtel‐Piotrowska Magdalena
Published: April 2018

Objective

The purpose of the current study is to test the factorial structure of the Mental Health Continuum‐Short Form (MHC‐SF) in Asian population.

Method

The study was conducted across three different Vietnamese samples (N = 2741). We present a comparison of the existing measurement models of the MHC‐SF using two methodological approaches: confirmatory factor analysis (CFA) and exploratory structural equation modeling (ESEM) (both in exploratory—using bi‐geomin rotation; and in confirmatory variant—using target rotation).

Results

The current report supported the targeted bifactor ESEM solution as better describing the factorial structure of the MHC‐SF than the originally assumed three‐factor solution in all samples.

Conclusion

The structure of the MHC‐SF is best represented as combination of the bifactor and ESEM model.
Qualitative analysis of the margins of restorations made with different filling resins
Authors: Ostapiuk Monika , Tarczydło Bożena , Surowska Barbara , Orłowski Mirosław , Tymczyna Barbara , Bachanek Teresa , Rzepecka Anna , Mróz Anna
Published: April 2018

Purpose: In this study the comparative results obtained from examinations of two different restorative composites with different cavities filling method are presented. Micro‐CT was used for the evaluation of the marginal integrity and quality of composite fillings in connection with microstructural investigations made by both optical and scanning electron microscopy.

Materials and Methods: The examinations of dental tooth filings in bulk‐fill technique were based on micro‐CT and microscopy observations. Two different restorative composites were selected for the study, namely SonicFill‐ bulk fill and conventional Filtek Z550.

Results: The experiment has shown that micro‐CT screening analysis for identification of individual components of tooth and fillings systems gives a high quality of images. Thanks to that it was possible to analyze and identify the porosity in the fillings. But the microscopy analysis has shown more information about the internal structure and quality of bonding between composite and enamel/dentin. The SonicFill gives better quality and bonding to structure of teeth than Filtek.

Conclusions: SonicFill's filling have more homogenous structure than Filtec. It has a greater share of reinforcement in the form of polygonal particles, in Filtek particles have a shape close to spherical. Sonic Fill gives a better adhesion to tooth.

Clinical Relevance: The evaluation of clinical relevance in this research is crucial to simplify the transfer of knowledge from research by materials engineering into practice in dentistry.
Demographic predictors of emotional intelligence among radiation therapists
Authors: Stami Trakis , Ritin Fernandez , Dominique Parrish
Published: April 2018

Introduction

Contemporary health care services are more productive and successful when their health professionals have emotional intelligence (EI). The objective of this study was to explore the demographic predictors of EI among radiation therapists working in cancer care centres in NSW, Australia.

Methods

Data were collected using a cross‐sectional self‐administered survey. Emotional intelligence was measured using the Trait Emotional Intelligence Questionnaire‐ Short version (TEIQue – SF). Multiple regression analysis was used to identify if age, years of experience, gender, highest level of education obtained or level of current employment were predictors of EI.

Results

A total of 205 radiation therapists participated in this study. The mean scores for Global EI, emotionality, self‐control, wellbeing and sociability dimensions were 5.16 (SD = 0.6), 5.3 (SD = 0.7), 4.9 (SD = 0.9), 5.7 (SD = 0.8) and 4.7 (SD = 0.8) respectively. Age and level of current employment were identified as predictors of global EI. Gender and level of education were significant predictors of the EI emotionality dimension. Levels of employment along with level of education were both significant predictors of the sociability dimension of EI.

Conclusions

Being a young radiation therapist, female, and having higher levels of employment and higher levels of education were predictors of EI. Given that level of education and level of employment are both amendable demographic factors, strategies to address these factors to reduce the effects of emotional struggle experienced by radiation therapists in their work need to be implemented.
Buffer gas additives (modifiers/shift reagents) in ion mobility spectrometry: Applications, predictions of mobility shifts, and influence of interaction energy and structure
Authors: Fernandez‐Maestre Roberto
Published: April 2018

Ion mobility spectrometry (IMS) is an analytical technique used for fast and sensitive detection of illegal substances in customs and airports, diagnosis of diseases through detection of metabolites in breath, fundamental studies in physics and chemistry, space exploration, and many more applications. Ion mobility spectrometry separates ions in the gas‐phase drifting under an electric field according to their size to charge ratio. Ion mobility spectrometry disadvantages are false positives that delay transportation, compromise patient's health and other negative issues when IMS is used for detection. To prevent false positives, IMS measures the ion mobilities in 2 different conditions, in pure buffer gas or when shift reagents (SRs) are introduced in this gas, providing 2 different characteristic properties of the ion and increasing the chances of right identification. Mobility shifts with the introduction of SRs in the buffer gas are due to clustering of analyte ions with SRs. Effective SRs are polar volatile compounds with free electron pairs with a tendency to form clusters with the analyte ion. Formation of clusters is favored by formation of stable analyte ion‐SR hydrogen bonds, high analytes' proton affinity, and low steric hindrance in the ion charge while stabilization of ion charge by resonance may disfavor it. Inductive effects and the number of adduction sites also affect cluster formation. The prediction of IMS separations of overlapping peaks is important because it simplifies a trial and error procedure. Doping experiments to simplify IMS spectra by changing the ion‐analyte reactions forming the so‐called alternative reactant ions are not considered in this review and techniques other than drift tube IMS are marginally covered.
An index of coastal thermal effects of El Niño Southern Oscillation on the Peruvian Upwelling Ecosystem
Authors: Quispe‐Ccalluari C. , Tam J. , Demarcq H. , Chamorro A. , Espinoza‐Morriberón D. , Romero C. , Dominguez N. , Ramos J. , Oliveros‐Ramos R.
Published: April 2018

The Peruvian Upwelling Ecosystem (PUE) is one of the most productive ecosystem in the world in terms of productivity and fish catches, partly because its geographical location is affected by remote physical processes, such as the interannual climate variability of the Equatorial Pacific Ocean (EPO), whose dominant signal is El Niño Southern Oscillation (ENSO). In order to assess the thermal effects of ENSO off Peru, a Peruvian Coastal Thermal Index (PCTI) was developed representing 87.7% of the total variation of the Sea Surface Temperature (SST) anomalies of the PUE. Between 1982 and 2014, the PCTI detected 12 warm periods and 16 cold periods in the PUE. PCTI had a linear trend component, a low frequency component and a noise component, with 1.5%, 94.5% and 4% contributions to the total variance, respectively. Wavelet analysis of PCTI showed significant peaks of variability between the years 1996 and 1999 between periods of 0.4 and 6 years. A regime shift in variance of PCTI was detected in 1999, with a lower variance between 1999 and 2014 than between 1982 and 1998, which agreed with the start of a cold phase of the Pacific Decadal Oscillation. The decrease of variance of the PCTI could be linked to an increase of the local winds associated with a higher intensity of the average state of South Pacific Anticyclone. This atmospheric change might have strengthened the coastal upwelling and counteracted the intensity of warm periods in the PUE. Finally, the comparison of different indexes allowed to detect four periods where neutral conditions occurred in the EPO while warm periods occurred in the PUE (1993, 2008, 2012 and 2014); and 1 period where a warm episode occurred in the EPO (2004–2005) while a neutral condition occurred in the PUE.
Seasonal precipitation forecast over Mexico based on a hybrid statistical–dynamical approach
Authors: Fuentes‐Franco Ramón , Giorgi Filippo , Pavia Edgar G. , Graef Federico , Coppola Erika
Published: April 2018

We introduce a new hybrid scheme for seasonal precipitation prediction over the Mexican territory. The scheme takes as input sea surface temperature (SST) predicted from the ECMWF System 4 coupled model (Sys4) identifying three predictors, namely SST over the western Pacific (WP), eastern Pacific (EP) and tropical Atlantic (TA); these predictors are used to forecast precipitation on a high‐resolution grid via a multiple regression model. Comparison of the performance of the hybrid scheme with the Sys4 model for ensemble re‐forecasts for the period 1982–2010 shows that the hybrid model adds skill to the Sys4 forecast, with higher correlations and Heidke skill scores throughout most of the Mexican territory, both in winter and summer. In winter the contribution of the EP is dominant in modulating precipitation via the effects of El Niño‐Southern Oscillation (ENSO), while in summer the contributions of the WP and TA are dominant in different Mexican regions. The hybrid scheme, applied to high‐resolution precipitation observations, also produces significant fine‐scale variability of forecast skill and mechanism contributions. Overall, we show that our hybrid approach can provide a useful tool to improve seasonal precipitation forecasts over Mexico.
Time‐domain measurement of pure rotational Raman collisional linewidths of ethane C2H6
Authors: Zhang H. , Billard F. , Faucher O. , Lavorel B.
Published: April 2018

The pure rotational Raman linewidths of the symmetric‐top molecule C2H6 are determined from a time‐resolved femtosecond experiment at room temperature and moderate pressure in a pump‐probe scheme. After excitation by a strong 100 fs‐duration nonresonant near infrared pump pulse, the molecular sample exhibits periodic post‐pulse alignment revivals that produce an anisotropic angular distribution of the molecular axis. Such molecular motion induces in turn a time‐dependent optical birefringence, which can be probed using a weak time‐delayed probe pulse. The Fourier transform of the temporal signal, recorded over a wide time delay range (several hundred picoseconds) for high frequency resolution, is directly related to the rotational Raman spectrum of ethane molecules. The Raman lines are analyzed with a frequency lineshape taking into account the collisional relaxation and the apparatus function. The linewidths are measured for rotational quantum numbers J=3 to J=30 in the pressure range 0.69–1.06 bar. A decrease of the collisional broadening coefficient is observed as J increases. These first measurements of pure rotational Raman linewidths of ethane are compared with previously reported infrared and far‐infrared values.
Factors influencing the choice of the Algarve region as a tourist destination: Does season matter?
Authors: Barreira Ana Paula , Cesário Marisa
Published: April 2018

The dissimilar ways in which tourists assess the attributes of a tourism destination in different seasons is an issue scarcely addressed in the literature. Here, we show that the characteristics of a tourism destination (the Algarve region, Portugal) are rated differently in peak (summer) and off‐peak (autumn/winter) seasons. Nationality is decisive in explaining the different assessments between seasons of the factors that group subsets of 17 attributes of the tourism destination. In general, the factors that are rated higher by domestic tourists during the summer are the same as those that are rated higher by foreign tourists in the autumn/winter.
Inducing Different Brain Injury Levels Using Shock Wave Lithotripsy
Authors: Divani Afshin A. , Salazar Pascal , Monga Manoj , Beilman Greg J. , SantaCruz Karen S.
Published: April 2018

Objectives

To assess the feasibility of inducing different severities of shock wave (SW)‐induced traumatic brain injury (TBI) using lithotripsy.

Methods

Wistar rats (n = 36) were divided into 2 groups: group 1 (n = 20) received 5 SW pulses, and group 2 (n = 16) received 15 SWs pulses. The SW pulses were delivered to the right side of the frontal cortex. Neurologic and behavioral assessments (Garcia test, beam walking, rotarod, and elevated plus maze) were performed at the baseline and at 3, 6, 24, 72, and 168 hours after injury. At day 7 after injury (168 hours), we performed cerebral angiography to assess the presence of cerebral vasospasm and vascular damage due to SW‐induced TBI. At the conclusion of the study, the animals were euthanized to assess damage to brain tissue using an overall histologic severity score.

Results

The Garcia score was significantly higher, and the anxiety index (based on the elevated plus maze) was significantly lower in group 1 compared to group 2 (P < .05). The anxiety index for group 1 returned to the baseline level in a fast nonlinear fashion, whereas the anxiety index for group 2 followed a distinct slow linear reduction. Cerebral angiograms revealed a more severe vasospasm for the animals in group 2 compared to group 1 (P = .027). We observed a statistically significant difference in the overall histologic severity scores between the groups. The median (interquartile range) overall histologic severity scores for groups 1 and 2 were 3.0 (2.75) and 6.5 (6.0), respectively (P = .023).

Conclusions

We have successfully established different SW‐induced TBI severities in our SW‐induced TBI model by delivering different numbers of SW pulses to brain tissue.
Reliability of Real‐time Ultrasound Imaging for the Assessment of Trunk Stabilizer Muscles: A Systematic Review of the Literature
Authors: Taghipour Morteza , Mohseni‐Bandpei Mohammad Ali , Behtash Hamid , Abdollahi Iraj , Rajabzadeh Fatemeh , Pourahmadi Mohammad Reza , Emami Mahnaz
Published: April 2018

Rehabilitative ultrasound (US) imaging is one of the popular methods for investigating muscle morphologic characteristics and dimensions in recent years. The reliability of this method has been investigated in different studies. As studies have been performed with different designs and quality, reported values of rehabilitative US have a wide range. The objective of this study was to systematically review the literature conducted on the reliability of rehabilitative US imaging for the assessment of deep abdominal and lumbar trunk muscle dimensions. The PubMed/MEDLINE, Scopus, Google Scholar, Science Direct, Embase, Physiotherapy Evidence, Ovid, and CINAHL databases were searched to identify original research articles conducted on the reliability of rehabilitative US imaging published from June 2007 to August 2017. The articles were qualitatively assessed; reliability data were extracted; and the methodological quality was evaluated by 2 independent reviewers. Of the 26 included studies, 16 were considered of high methodological quality. Except for 2 studies, all high‐quality studies reported intraclass correlation coefficients (ICCs) for intra‐rater reliability of 0.70 or greater. Also, ICCs reported for inter‐rater reliability in high‐quality studies were generally greater than 0.70. Among low‐quality studies, reported ICCs ranged from 0.26 to 0.99 and 0.68 to 0.97 for intra‐ and inter‐rater reliability, respectively. Also, the reported standard error of measurement and minimal detectable change for rehabilitative US were generally in an acceptable range. Generally, the results of the reviewed studies indicate that rehabilitative US imaging has good levels of both inter‐ and intra‐rater reliability.
Teatime on Mount Kilimanjaro: Assessing climate and land‐use effects on litter decomposition and stabilization using the Tea Bag Index
Authors: Becker Joscha N. , Kuzyakov Yakov
Published: April 2018

Decomposition is one of the most important processes in ecosystem carbon (C) and nutrient cycles and is a major factor controlling ecosystem functions. The functioning of Afromontane ecosystems and their ability to provide ecosystem services are particularly threatened by climate and land‐use change. Our objectives were to assess the effects of climatic conditions (elevation and seasonality) and land‐use intensity on litter decomposition and C stabilization in 10 ecosystems along the unique 3,000‐m elevation gradient of Mt. Kilimanjaro.

Tea Bag Index parameters (decomposition‐rate‐constant k and stabilization‐factor S) were used to quantify decomposition of standardized litter substrate. Nine pairs of tea bags (green and rooibos tea) were exposed in each ecosystem during the short‐wet, warm‐dry, long‐wet and cold‐dry season.

Decomposition rate increased from k = 0.007 in savanna (SAV; 950‐m elevation), up to a maximum of k = 0.022 in montane cloud forest (2,100 m). This was followed by a 50% decrease in (sub‐)alpine ecosystems (>4,000 m). SAV experienced the strongest seasonal variation, with 23‐times higher S values in dry season compared with wet season. The conversion of SAV to maize monocultures (~1,000 m) and traditional agroforestry to large‐scale coffee plantations (~1,300 m) increased mean k values, and stabilization factors were about one‐third lower.

Forests between 1,900 and 2,100 m represent the zone of sufficient moisture and optimal temperature conditions. Seasonal moisture (lower slope) and temperature limitation (alpine zone) decreases litter decomposition. Mt. Kilimanjaro ecosystems are highly sensitive to land‐use change, which accelerates ecosystem cycles and decreases C stabilization.
Incorporating Si3N4 into PEEK to Produce Antibacterial, Osteocondutive, and Radiolucent Spinal Implants
Authors: Pezzotti Giuseppe , Marin Elia , Adachi Tetsuya , Lerussi Federica , Rondinella Alfredo , Boschetto Francesco , Zhu Wenliang , Kitajima Takashi , Inada Kosuke , McEntire Bryan J. , Bock Ryan M. , Bal B. Sonny , Mazda Osam
Published: April 2018

Polyetheretherketone (PEEK) is a popular polymeric biomaterial which is primarily used as an intervertebral spacer in spinal fusion surgery; but it is developed for trauma, prosthodontics, maxillofacial, and cranial implants. It has the purported advantages of an elastic modulus which is similar to native bone and it can be easily formed into custom 3D shapes. Nevertheless, PEEK's disadvantages include its poor antibacterial resistance, lack of bioactivity, and radiographic transparency. This study presents a simple approach to correcting these three shortcomings while preserving the base polymer's biocompatibility, chemical stability, and elastic modulus. The proposed strategy consists of preparing a PEEK composite by dispersing a minor fraction (i.e., 15 vol%) of a silicon nitride (Si3N4) powder within its matrix. In vitro tests of PEEK composites with three Si3N4 variants—β‐Si3N4, α‐Si3N4, and β‐SiYAlON—demonstrate significant improvements in the polymer's osteoconductive versus SaOS‐2 cells and bacteriostatic properties versus gram‐positive Staphylococcus epidermidis bacteria. These properties are clearly a consequence of adding the bioceramic dispersoids, according to chemistry similar to that previously demonstrated for bulk Si3N4 ceramics in terms of osteogenic behavior (vs both osteosarcoma and mesenchymal progenitor cells) and antibacterial properties (vs both gram‐positive and gram‐negative bacteria).
Counter‐stereotypical products: Barriers to their adoption and strategies to overcome them
Authors: Gill Tripat , Lei Jing
Published: April 2018

Counter‐stereotypical products (CSPs) are targeted at groups that are opposite to the stereotypical users of these products (e.g., face‐cream for men, construction tools for women). Such products entail adoption barriers, as they are associated with a dissociative out‐group (e.g., men avoid products used by women). A theoretical framework is developed to investigate such barriers by outlining consumers’ cognitive and affective responses to CSPs; namely: stereotyping (CSP is considered appropriate only for the stereotypical user group), subtyping/subgrouping (CSP is useful for certain individuals or subgroups), and derogating (disparaging the CSP due to a perceived threat to self). Study 1 verifies these responses and demonstrates their effect on the evaluation of CSPs targeting men versus women. Overall, CSPs targeting men faced more barriers than those targeting women, and this was especially so for publicly consumed CSPs (e.g., purse for men) as compared to privately consumed ones (e.g., hair‐remover for men). Study 2 examined the effect of a common marketing tool—product design color (e.g., using blue for men and pink for women)—in reducing the above barriers. It was found that blue is effective in reducing stereotype‐based barriers for CSPs targeting men. For CSPs targeting women, using pink was only effective for women scoring high on femininity, and it backfired for those scoring low on femininity.
An Epigenetic Signature in Adipose Tissue Is Linked to Nicotinamide N‐Methyltransferase Gene Expression
Authors: Crujeiras Ana B. , Pissios Pavlos , Moreno‐Navarrete Jose M. , Diaz‐Lagares Angel , Sandoval Juan , Gomez Antonio , Ricart Wilfredo , Esteller Manel , Casanueva Felipe F. , Fernandez‐Real Jose M.
Published: April 2018

Scope

The enzyme nicotinamide N‐methyltransferase (NNMT) is a major methyltransferase in adipose tissue. We hypothesized an epigenetic signature in association with NNMT gene expression in adipose tissue.

Methods and results

The global human methylome was analyzed in visceral adipose tissue (VAT) from morbidly obese patients using the Infinium Human Methylation 450 BeadChip array (discovery cohort: n = 11). The findings were confirmed in two additional independent cohorts (cohort 1: n = 60; BMI 20–60 kg m−2 and cohort 2: n = 40; BMI > 40 kg m−2) and validated after weight loss (using microarray data). Among the genes associated with the largest methylation fold change were genes related to metabolic processes, proliferation, inflammation, and extracellular matrix remodeling, such as COL23A1, PLEC1, FBXO21, STEAP3, RGS12, IGDCC3, FOXK2, and ORAI2. In fact, the results showed 577 differentially methylated CpG sites (DMCpGs) associated with the NNMT expression levels, with low methylation levels paralleling high NNMT expression. The expression of FBXO21 and FOXK2 was specifically modified after weight loss concomitantly with a decrease in NNMT expression and inflammation‐related genes. Interestingly, the adipose tissue NNMT gene expression correlated with markers of adipose tissue inflammation.

Conclusions

The expression of NNMT in VAT is associated with a specific methylome signature involving genes linked to adipose tissue metabolic pathophysiology.
Design of a textile antenna with artificial magnetic conductor for wearable applications
Authors: Mersani Ameni , Lotfi Osman , Ribero Jean‐Marc
Published: April 2018

With the development of modern wireless technologies and the miniaturization of antennas and electrical systems, the use of antennas on the human body for Wi‐Fi applications has become important. However, integrating the antenna near the body immediately raises the question about the protection of the body and the radiation effectiveness of the antenna. One solution that has recently attracted great attention is the use of high impedance surfaces (HIS), which is studied here for the antennas integrated on clothes. Indeed, the HIS greatly reduces the radiation back face of the antenna, thus reducing the value of the specific absorption rate in the presence of the body. In this article, we present a dual‐band antenna placed above an artificial magnetic conductor (AMC). The AMC used has the smallest dimensions and makes it possible to obtain the behavior of a perfect magnetic conductor at 2.45 and 5.8 GHz.
A multiband dual‐standard MIMO antenna system based on monopoles (4G) and connected slots (5G) for future smart phones
Authors: Ikram M. , Sharawi M. S. , Shamim A. , Sebak A.
Published: April 2018

In this work, a 4G/5G multiple‐input multiple‐output (MIMO) antenna system is presented for smart phone applications. The 4G antenna operates from 1900 to 3212 MHz and 3517 to 3712 MHz with 1312 (69%) and 195 (5.5%) MHz measured bandwidths, respectively. The 5G antenna covers 25.7–30.50 GHz band with 4.8 GHz (18.7%) measured bandwidth. The 4G MIMO antenna system is based on 4‐element wideband monopoles, while the 5G one is based on 2‐element linear connected arrays (LCA). Four slots are etched to improve the isolation between the 4G MIMO antenna elements and then a 4 × 1 power divider/combiner is used to excite two of these slots to act as a LCA at mm‐waves. The concept of dual function ground slots is very useful to implement 4G and 5G MIMO antenna systems on the single substrate. The proposed design is fabricated on RO4350B substrate with a height of 0.76 mm and dielectric constant of 3.5. The overall size of the substrate is 115 × 65 × 0.76 mm3. The integrated wideband 4G/5G antenna system is a compact, low profile, and suitable for future smart phone applications. Isolation obtained was at least 15 dB and the envelope correlation coefficient (ECC) values did not exceed 0.16 between all elements.
Self‐interference cancellations for full‐duplex RF front‐end using a broadband phase‐slope adjuster
Authors: You Fei , Chen Guoqiang
Published: April 2018

With improved wide‐band performances compared to classical RF signal cancellation circuits, an alternate self‐interference cancellation method is presented for a full‐duplex front‐end involving a phase‐slope adjuster. This solution can adapt frequency‐dependent phase mismatch in the cancellation path. This adjuster consists of a hybrid coupler and two varactor diodes, which can expand a single cancellation sweet spot to a continuous frequency range because of a newly introduced fine phase slope tuning capability. From measurement results, a single‐loop demo circuit can suppress interferences by 42 and 32 dB in 20 and 60 MHz bandwidth, respectively.
Compact planar multiband MIMO antenna based on composite right/left‐handed transmission line for mobile phone applications
Authors: Luo Xin‐Shuai , Weng Zi‐bin , Zhang Wei‐Jun , Yang Lei
Published: April 2018

A novel compact planar multiband multiple‐input multiple‐out (MIMO) antenna based on composite right/left handed transmission line (CRLH‐TL) for mobile phone applications is presented in this article. The proposed MIMO antenna consists of two asymmetric antenna elements and two‐sided shorted ground, which is designed by zeroth‐order resonant theory to achieve compact performance. The proposed antenna elements cover the communication bands in 698–960 MHz and 1710–2690 MHz with the planar size of 16 × 56 mm2 and 12 × 56 mm2, respectively. Acceptable agreement between simulated and experimental results over the desired operating bands is observed. The envelop correlation coefficients are calculated by the S parameters.
A novel four‐port high isolation MIMO antenna design for high‐capacity wireless applications
Authors: Liu Yu , Liu Ming , Xu Fang , Xu Jie , Huang Xiangdong
Published: April 2018

A novel four‐port multiple‐input‐multiple‐output (MIMO) antenna with high isolation is proposed in this article. This antenna is fabricated on a FR4 substrate with a compact size of 84 mm × 26 mm × 1.6 mm (0.98λ × 0.3λ × 0.019λ, λ is the wavelength at 3.5 GHz). The design adopts curved slot‐lines on both sides of the substrate to enhance the isolation level and radiation in the working bands. The measured results show that the fabricated prototype can cover the working bands of advanced TD‐LTE, WiLAN/WiFi, and cognitive radio applications with good radiation pattern characteristics. Furthermore, the isolation among multiple ports exceeds 15, 28, and 16 dB in the three working bands respectively, and high channel capacities could be achieved by this four‐port design.
Design of wideband LTCCBPF with notch band exploiting one‐third isosceles triangular resonator
Authors: Xiangjun Zhang , Zhang Hao , Chen Yiming
Published: April 2018

The design of a novel multilayer wideband bandpass filter with one notch band is presented in this letter. The proposed filter structure is composed of one‐third isosceles triangular substrate integrated waveguide (SIW) cavities and the coupled striplines. The SIW cavities structure generates multiple resonant modes which are used to realize the wideband bandpass filter. Owing to the low temperature co‐fired ceramic technology, the stripline and the SIW cavity are printed on multilayer ceramic, which makes the filter compact. The filter have a compact volume of 6.0 × 8.0 × 0.4 mm3. The measured results exhibit the bandpass filter achieves a center frequency of 15 GHz with a 3 dB fractional bandwidth of 33.33% and more than 15 dB attenuation at skirt band. The width of the notch band was about 600 MHz centered at 15.5 GHz. The measured results of fabricated filter are in close agreement with the simulated ones.
Design and development of UWB (3.0–42.8 GHz) truncated annular microstrip monopole antenna
Authors: Singh R. K. , Pujara Dhaval
Published: April 2018

A novel truncated annular microstrip monopole antenna with partial ground for ultra‐wideband (UWB) applications is designed and fabricated. Proposed antenna consists of overlapping a circular patch with truncated annular patch, fed by a stepped microstrip line designed on commercially available low cost FR‐4 substrate covering the UWB band from 3.0 to 42.8 GHz for return‐loss better than −10 dB. The designed antenna is very compact in size occupying 35 × 32 × 1.6 mm3. The full‐wave electromagnetic simulation software HFSS was used to estimate the return‐loss, radiation patterns, and gain of a proposed antenna. The measured results of return‐loss are also presented in this article.
Dual band omnidirectional circularly polarized antenna using EZR and MZR modes
Authors: Lee Jae‐Gon , Um Kwi Seob , Lee Jeong‐Hae
Published: April 2018

A dual band omnidirectional circularly polarized (CP) antenna is presented based upon new concept of combining two orthogonal modes of epsilon‐zero resonance (EZR) and mu‐zero resonance (MZR) in this article. The antenna has the CP characteristic by two circularly ring‐structured double negative (DNG) transmission lines. One DNG transmission line has higher frequencies of EZR and lower frequency of MZR while the other DNG transmission line has higher frequencies of MZR and lower frequency of EZR. The EZR and MZR modes at the same frequency have a vertical and a horizontal polarization with 90° phase difference, respectively. In the EZR mode, a vertical polarization is generated like an electric monopole so that the EZR antenna radiates omnidirectionally. The MZR antenna makes a horizontal polarization by the circular ring current like a magnetic dipole loop which also radiates omnidirectionally. The analysis and design of the antenna are performed according to theory and simulation based on a dispersion diagram and E‐field distribution. Finally, the reasonable performances of the antenna such as a reflection coefficient, a CP gain, an axial ratio, and a far‐field radiation pattern are obtained in dual band.
Miniaturized switched line MEMS phase shifter
Authors: Anitha G. , Usha Kiran K.
Published: April 2018

In this article, we propose a novel miniaturized MEMS phase shifter which relies on the loading of meander line and Complementary split ring resonators meta‐material conception to resolve the issues of miniaturization and insertion loss in the transmission line. The proposed phase shifter purely entrenched upon the switchable delay line and a reference line design, which is inline with a metal contact series switch.The phase shifter and RF switches are built on a 50 Ω coplanar waveguide transmission line. One of the unique features of the switch is shaped with triangular to obtain good RF and mechanical characteristics in terms of return loss, isolation, insertion loss, pull in voltage, and stress profile. The result shows, that the mechanical performance of the triangular series switch has low actuation voltage of 5.67 V with a stress value of 5 MPa and the calculated switching time is 3.9 µs. The RF performance of the triangular switch showed an insertion loss of −0.2 with −20 dB of a return loss in the ON state, whereas, in the OFF state, isolation is around −26 dB at DC −20 GHz. The proposed switch was used to build the miniature phase shifter. The average values of the miniaturized 5‐bit phase shifter (11.25, 22.5°, 45°, 90°, and 180°) return loss and insertion loss is −16.68 and −1.35 dB and phase error is less than 0.57°. Overall, 30% size reduction in the miniaturized phase shifter is obtained using triangular single pole single throw switches.
Triple‐port, two‐mode based two element cylindrical dielectric resonator antenna for MIMO applications
Authors: Das Gourab , Sharma Anand , Gangwar Ravi Kumar , Sharawi Mohammad S.
Published: April 2018

In this letter, a triple‐port multiple‐input–multiple‐output (MIMO) cylindrical dielectric resonator based antenna (cDRA) supporting 2 simultaneous operating modes is presented. The cDRAs are excited by 3 ports supporting MIMO operation. Mode‐1 is an array mode achieved by exciting the 2 element cDRA array via a simple combiner at port‐1. Ports‐ 2 and −3 support individual element excitation via coaxial probes for mode‐2 yielding individual element MIMO operation. The isolation between ports‐1, 2, and 3 is improved by generating orthogonal modes in the cDRA via proper excitation. The isolation between ports‐2 and 3 is improved by etching 2 C‐shaped defected ground structure slits. For all the cases, the isolation between the ports exceeds 20 dB over the operating band. The presented dual‐mode 3‐port MIMO antenna covers the bands between 5.15 and 6.0 GHz.
Tailoring Uniform Copolymer Composition Distribution via Policy II RAFT Solution Copolymerization of Styrene and Butyl Acrylate
Authors: Jiang Jie , Wang Wen‐Jun , Li Bo‐Geng , Zhu Shiping
Published: April 2018

Controlled radical polymerization (CRP) is regarded as a powerful method to design various chain structures. Semibatch monomer feeding strategies in CRP are widely used for targeting the polymer products with desired copolymer composition distribution (CCD) and molecular weight distribution, which define the properties of polymer materials. In this work, the uniform CCD in reversible addition–fragmentation transfer (RAFT) solution copolymerization is targeted via model‐based semibatch Policy II. A RAFT solution copolymerization model is first developed and correlated with batch styrene (St) and butyl acrylate (BA) copolymerization experimental data. St/BA copolymers having three different uniform compositions are produced by the comonomer feeding Policy II. Heat and concentration analysis prove feasibility of the policy. Simulation results show that the uniform CCD can be achieved by both Policy II and Policy I, compared with starved feeding and constant feeding. Policy II gives higher and more steady rates than Policy I.
Controlling motion artefact levels in MR images by suspending data acquisition during periods of head motion
Authors: Castella Rémi , Arn Lionel , Dupuis Estelle , Callaghan Martina F. , Draganski Bogdan , Lutti Antoine
Published: April 2018

Purpose

Head movements are a major source of MRI artefacts. Prospective motion correction techniques significantly improve data quality, but strong motion artefacts may remain in the data. We introduce a framework to suspend data acquisition during periods of head motion over a predefined threshold.

Methods

Data was acquired with prospective motion correction and an external optical tracking system. A predictor of motion impact was introduced that accounts for the amplitude of the signal acquired at the time of the motion. From this predictor, a threshold was defined to trigger the suspension of data acquisition during periods of motion. The framework was tested on 5 subjects, 2 motion behaviors, and 2 head coils (20 and 64 channels).

Results

The best improvements in data quality were obtained for a threshold value of 0, equivalent to suspending the acquisition based on head speed alone, at the cost of a long prolongation of scan time. For threshold values ∼3.5e−4, image quality was largely preserved, and prolongation of scan time was minimal. Artefacts occasionally remained with the 64‐channel head coil for all threshold values, seemingly due to head movement in the sharp sensitivity profile of this coil.

Conclusion

The proposed suspension strategy is more efficient than relying on head speed alone. The threshold for suspension of data acquisition governs the tradeoff between image degradation due to motion and prolonged scan time, and can be tuned by the user according to the desired image quality and participant's tolerability.
T1 weighted fat/water separated PROPELLER acquired with dual bandwidths
Authors: Rydén Henric , Berglund Johan , Norbeck Ola , Avventi Enrico , Skare Stefan
Published: April 2018

Purpose

To describe a fat/water separated dual receiver bandwidth (rBW) spin echo PROPELLER sequence that eliminates the dead time associated with single rBW sequences. A nonuniform noise whitening by regularization of the fat/water inverse problem is proposed, to enable dual rBW reconstructions.

Methods

Bipolar, flyback, and dual spin echo sequences were developed. All sequences acquire two echoes with different rBW without dead time. Chemical shift displacement was corrected by performing the fat/water separation in k‐space, prior to gridding. The proposed sequences were compared to fat saturation, and single rBW sequences, in terms of SNR and CNR efficiency, using clinically relevant acquisition parameters. The impact of motion was investigated.

Results

Chemical shift correction greatly improved the image quality, especially at high resolution acquired with low rBW, and also improved motion estimates. SNR efficiency of the dual spin echo sequence was up to 20% higher than the single rBW acquisition, while CNR efficiency was 50% higher for the bipolar acquisition. Noise whitening was deemed necessary for all dual rBW acquisitions, rendering high image quality with strong and homogenous fat suppression.

Conclusion

Dual rBW sequences eliminate the dead time present in single rBW sequences, which improves SNR efficiency. In combination with the proposed regularization, this enables highly efficient T1‐weighted PROPELLER images without chemical shift displacement.
Design of programs to train pelvic floor muscles in men with urinary dysfunction: Systematic review
Authors: Hall Leanne M. , Aljuraifani Rafeef , Hodges Paul W.
Published: April 2018

Aims

Pelvic floor muscle training (PFMT) is a first line conservative treatment for men with urinary dysfunction, but reports of its efficacy are variable. This study aimed to systematically review the content of PFMT programs used for urinary dysfunction in men.

Methods

Electronic databases (PubMed, CINAHL, EMBASE, Cochrane, PEDro) were searched for studies that used PFMT in the treatment of adult men with urinary dysfunction. Details of PFMT treatment sessions and home exercise protocols were extracted. Criteria specific to PFMT were developed, based on the Consensus on Exercise Reporting Template, and applied to all studies to measure the comprehensiveness of the PFMT description in the manuscript.

Results

Results from the 108 included studies indicate substantial heterogeneity in both the content of PFMT and the quality of reporting of the components of the exercise regimes. There was notable disparity in the muscles targeted by the interventions (and few focused on urethral control despite the use in management of urinary conditions) and the intensity of the programs (eg, 18‐240 contractions per day). Most studies were missing key details of description of the PFMT programs (eg, the position in which the pelvic floor muscle [PFM] contraction was taught and how it was assessed, methods used to ensure exercise adherence).

Conclusions

Variation in content of PFMT programs is likely to contribute to variation in the reported efficacy for management of urinary dysfunction in men, and unclear description of the details of the evaluated programs makes it difficult to identify the effective/ineffective components. PROSPERO registration number CRD42017071038.
A quasi‐experimental study of the effect of teaching Orem's self‐care model on nursing students’ clinical performance and patient satisfaction
Authors: Malekzadeh Javad , Amouzeshi Zahra , Mazlom Seyed Reza
Published: April 2018

Aims

This study aims to determine the effect of teaching Orem's self‐care model on nursing students’ clinical performance and patient satisfaction.

Design

The study was a quasi‐experimental, non‐randomized, two‐group design with posttest.

Methods

In this quasi‐experimental study, 66 nursing students were selected via convenience sampling method. The intervention group was trained based on Orem's self‐care model and the control group based on the routine nursing process method. Both groups cared patients for a week. Students’ performance was evaluated during the clinical course by performance observation checklist and patient satisfaction was assessed at the end of clinical course using patient satisfaction form. Data were analysed in SPSS software using chi‐squared, Fisher Exact test, Mann–Whitney, t test and two‐way ANOVA.

Results

Clinical performance evaluation mean score in the intervention group was significantly higher than that of the control group. However, patient satisfaction scores in both the control group and intervention group did not show statistically significant differences. Orem's self‐care model showed a 23% improvement in students’ performance. It is recommended to use Orem's self‐care model for undergraduate courses, especially in clinical training.
Weight Stigma in Men: What, When, and by Whom?
Authors: Himmelstein Mary S. , Puhl Rebecca M. , Quinn Diane M.
Published: April 2018

Objective

This study assessed the weight stigma experiences of men, examining characteristics of men who experienced weight stigma versus men who did not.

Methods

Data from three samples of men were examined (N = 1,513). Sample 1 consisted of men with obesity at elevated risk for weight stigma. Sample 2 comprised a convenience online panel. Sample 3 included men from a national online panel of US adults. Men in all samples completed almost identical questionnaires assessing demographics, anthropometrics, weight stigma, and dieting.

Results

Approximately 40% of men reported experiencing weight stigma. Weight stigma was associated with increased odds of having a BMI consistent with underweight or obesity relative to normal weight. Verbal mistreatment was the most common form of weight stigma experienced across all life stages for men. The most common sources of weight stigma were peers, family members, and strangers. Men reporting weight stigma were younger and less likely to be married, had higher BMIs, and were more likely to have tried to lose weight in the past year relative to men not reporting weight stigma.

Conclusions

Understanding differences among men as a function of weight stigma is important for practitioners, as it can identify men who may most benefit from intervention.