bluuebunny/crossref_metadata_2025_split huggingface dataset:
Revealing sub‐voxel motions of brain tissue using phase‐based amplified MRI (aMRI)
Authors: Terem Itamar , Ni Wendy W. , Goubran Maged , Rahimi Mahdi Salmani , Zaharchuk Greg , Yeom Kristen W. , Moseley Michael E. , Kurt Mehmet , Holdsworth Samantha J. 
Published: May 2018

PurposeAmplified magnetic resonance imaging (aMRI) was recently introduced as a new brain motion detection and visualization method. The original aMRI approach used a video‐processing algorithm, Eulerian video magnification (EVM), to amplify cardio‐ballistic motion in retrospectively cardiac‐gated MRI data. Here, we strive to improve aMRI by incorporating a phase‐based motion amplification algorithm.MethodsPhase‐based aMRI was developed and tested for correct implementation and ability to amplify sub‐voxel motions using digital phantom simulations. The image quality of phase‐based aMRI was compared with EVM‐based aMRI in healthy volunteers at 3T, and its amplified motion characteristics were compared with phase‐contrast MRI. Data were also acquired on a patient with Chiari I malformation, and qualitative displacement maps were produced using free form deformation (FFD) of the aMRI output.ResultsPhantom simulations showed that phase‐based aMRI has a linear dependence of amplified displacement on true displacement. Amplification was independent of temporal frequency, varying phantom intensity, Rician noise, and partial volume effect. Phase‐based aMRI supported larger amplification factors than EVM‐based aMRI and was less sensitive to noise and artifacts. Abnormal biomechanics were seen on FFD maps of the Chiari I malformation patient.ConclusionPhase‐based aMRI might be used in the future for quantitative analysis of minute changes in brain motion and may reveal subtle physiological variations of the brain as a result of pathology using processing of the fundamental harmonic or by selectively varying temporal harmonics. Preliminary data shows the potential of phase‐based aMRI to qualitatively assess abnormal biomechanics in Chiari I malformation.
Chemical exchange saturation transfer fingerprinting for exchange rate quantification
Authors: Zhou Zhengwei , Han Pei , Zhou Bill , Christodoulou Anthony G. , Shaw Jaime L. , Deng Zixin , Li Debiao 
Published: May 2018

PurposeThere is an increased interest to determine the exchange rate using CEST to provide pH information. However, current CEST quantification methods require lengthy scan times and do not address magnetization transfer effects. The purpose of this work was to apply the magnetic resonance fingerprinting (MRF) concept to CEST to achieve more efficient and accurate exchange rate quantification.MethodsThe proposed CEST fingerprinting method used varying saturation powers and saturation times to create unique signal evolutions for different exchange rates. The acquired signal was matched to a predefined dictionary to determine the exchange rate. The magnetization transfer effects were also addressed in the framework of CEST fingerprinting: The simulated dictionary could predict the signal curves without magnetization transfer effects, and comparing the dictionary to the acquired signals allowed the correction of the magnetization transfer effects. The CEST fingerprinting method was compared with the conventional pulsed quantitative CEST method using omega plots in the creatine phantom study.ResultsThe CEST fingerprinting method has a significantly reduced scan time (10 minutes versus 50 minutes) while providing more accurate exchange rate quantification using literature values as the reference.ConclusionIn this study, we demonstrate that CEST fingerprinting is more efficient (5 times faster) compared with pulsed quantitative CEST. It is also shown that the results of the proposed CEST fingerprinting technique are much closer to the literature values than pulsed quantitative CEST at 3 T.
Failure Mode, Effect, and Criticality Analysis of the Parenteral Nutrition Process in a Mother–Child Hospital: The AMELIORE Study
Authors: Boulé Marianne , Lachapelle Sophie , Collin‐Lévesque Laurence , Demers Émile , Nguyen Christina , Fournier‐Tondreau Marylou , Thibault Maxime , Lebel Denis , Bussières Jean‐François 
Published: May 2018

AbstractBackgroundThe parenteral nutrition (PN) process is complex and involves multiple steps and substeps, especially in pediatrics and neonatology, given the particular needs of these patients. The objective of this study was to perform a critical analysis of the PN process at the Centre Hospitalier Universitaire Sainte‐Justine to determine which potential pitfalls are related to this process and which should be prioritized when implementing corrective measures.MethodsThis is a Failure Mode, Effect, and Criticality Analysis (FMECA) study. A multidisciplinary team assessed each step of the PN process and identified associated failure modes. Adapted rating scales were used to determine severity, frequency, and detectability of the failure modes. Ratings were established through multidisplinary consensus, and a criticality index (CI) was calculated for each failure mode.ResultsA total of 265 failure modes were identified in the 5 major steps of the PN process. The failure mode with the highest CI was the inscription of an inaccurate weight at prescription, with a CI of 800. The step with the highest cumulative CIs was administration to patients, with a CI sum of 7691. Various recommendations aimed at minimizing the risks associated with the PN process were made following this FMECA. Additional interventions are expected to emanate from this project because data will be presented throughout the departments involved.ConclusionThis study is a successful example for other hospitals interested in carrying out the same kind of healthcare improvement initiative.
A qualitative study of assistant nurses' experiences of palliative care in residential care
Authors: Udo Camilla , Neljesjö Maria , Strömkvist Ingegerd , Elf Marie 
Published: May 2018

AbstractAimTo explore assistant nurses' experiences and perceptions of both positive and negative aspects of providing palliative care for older people in residential care facilities.DesignA qualitative explorative study.MethodsCritical incidents were collected through semi‐structured face‐to‐face interviews and analysed by performing a qualitative content analysis.ResultsA total of 40 critical incidents from daily work was described by assistant nurses. The results showed that close cooperation between unlicensed and licensed professionals was crucial to provide good care but was sometimes negatively affected by the organizational structure. The availability of professionals was identified as a critical factor in providing good care at the end of life in a consultative organization. The most prominent findings were those that indicated that, especially in a consultative organization, there seems to be a need for clear roles, comprehensive and clear care plans and a solid support structure to ensure continuity of care.
Chromogenic and Fluorogenic Probes for the Detection of Illicit Drugs
Authors: Garrido Eva , Pla Luis , Lozano‐Torres Beatriz , El Sayed Sameh , Martínez‐Máñez Ramón , Sancenón Félix 
Published: May 2018

AbstractThe consumption of illicit drugs has increased exponentially in recent years and has become a problem that worries both governments and international institutions. The rapid emergence of new compounds, their easy access, the low levels at which these substances are able to produce an effect, and their short time of permanence in the organism make it necessary to develop highly rapid, easy, sensitive, and selective methods for their detection. Currently, the most widely used methods for drug detection are based on techniques that require large measurement times, the use of sophisticated equipment, and qualified personnel. Chromo‐ and fluorogenic methods are an alternative to those classical procedures.
Synthesis and Application of Dendritic Fibrous Nanosilica/Gold Hybrid Nanomaterials
Authors: Byoun Wongyun , Jung Soeun , Tran Ngoc Minh , Yoo Hyojong 
Published: May 2018

AbstractMorphologically unique silica nanoparticles can be used as effective templates to prepare silica–metal hybrid nanomaterials, which are highly applicable in a variety of areas. Mesoporous silica nanoparticles, which have high surface areas and an abundance of pores, can be used to synthesize mesoporous silica core–metal shell nanostructures with catalytically active sites. In this work, dendritic fibrous nanosilica (DFNS) with a high surface area is successfully employed as a template to synthesize DFNS/Au hybrid nanomaterials. Au nanodots are initially synthesized through the selective reduction of Au ions on the surface of the DFNS after surface modification to form DFNS/Au dots. A seed‐mediated growth method is used to controllably grow Au nanoparticles on the DFNS/Au dots to generate DFNS core–Au nanoparticles shell nanohybrids (DFNS/Au NPs) and DFNS core–Au layer shell nanohybrids (DFNS/Au layers). The catalytic activities of DFNS/Au NPs and DFNS/Au layers in the 4‐nitrophenol reduction reaction are compared.
Observers' response to facial disfigurement from head and neck cancer
Authors: Cho Joowon , Fingeret Michelle Cororve , Huang Sheng‐Cheng , Liu Jun , Reece Gregory P. , Markey Mia K. 
Published: May 2018

AbstractObjectiveOur long‐term goal is to develop a normative feedback intervention to support head and neck cancer patients in forming realistic expectations about how other people in non‐social group settings will respond to their appearance. This study aimed to evaluate the relationship between observer ratings of facial disfigurement and observer ratings of emotional response when viewing photographs of faces of head and neck cancer patients.MethodsSeventy‐five (75) observers rated their emotional response to each of 144 facial photographs of head and neck cancer patients using the Self‐Assessment‐Manikin and rated severity of facial disfigurement on a 9‐point scale. Body image investment of the observers was measured using the Appearance Schemas Inventory‐Revised. A standardized multiple regression model was used to assess the relationship between observer ratings of facial disfigurement and observer ratings of emotional response, taking into consideration the age and sex of the patient depicted in the stimulus photograph, as well as the age, sex, and body image investment of the observer.ResultsObservers who had a strong emotional response to a patient's facial photograph tended to rate the patient's facial disfigurement as more severe (standardized regression coefficient β = 0.328, P < 0.001). Sex and age of the observer had more influence on the rating of facial disfigurement than did the patient's demographic characteristics. Observers more invested in their own body image tended to rate the facial disfigurement as more severe.ConclusionsThis study lays the groundwork for a normative database of emotional response to facial disfigurement.
Dihydrazinium Nitrates Derived from Malonic and Iminodiacetic Acid
Authors: Klapötke Thomas M. , Krumm Burkhard , Reith Thomas 
Published: May 2018

AbstractSeveral hydrazinium nitrates were synthesized on the basis of malonic acid and iminodiacetic acid. The reaction of the corresponding ethyl esters with hydrazine hydrate yielded the dihydrazides in good‐to‐high yields and high purity. Subsequent protonation with diluted nitric acid or hydrochloric acid resulted in the corresponding nitrate and chloride salts. The neutral compounds and their salts were fully characterized, including multinuclear NMR spectroscopy, vibrational analysis, X‐ray diffraction, differential thermal analysis and elemental analysis. The energies of formation were calculated with the Gaussian program package and the detonation parameters were predicted using the Explo5 computer code.
Development and evaluation of cationic amphiphilic antimicrobial 2,5‐diketopiperazines
Authors: Labrière Christophe , Kondori Nahid , Caous Josefin Seth , Boomgaren Marc , Sandholm Kerstin , Ekdahl Kristina N. , Hansen Jørn H. , Svenson Johan 
Published: May 2018

Both pathogenic bacteria and fungi are developing resistance to common antimicrobial treatment at an alarming rate. To counteract this development, it is of essence to develop new classes of antimicrobial agents. One such class is antimicrobial peptides, most of which are derived from the innate immune system. In this study, a series of novel 2,5‐diketopiperazines were designed, synthesized, and evaluated for their antimicrobial abilities. The compounds were designed to probe the pharmacophore dictated for short linear mimics of antimicrobial cationic peptides, and as such, the compounds contain a range of cationic and hydrophobic functionalities. Several of the prepared compounds displayed high antimicrobial activities toward bacteria and also against human pathogenic fungi. Of particular interest was the high activity toward fungal strains with an inherent increased resistance toward conventional antifungal agents. The most effective compounds displayed inhibition of Candida glabrata and Candida krusei growth at concentrations between 4 and 8 μg/mL, which is comparable to commercial antifungal agents in use. Structure activity relationship studies revealed a similar dependence on cationic charge and the volume of the hydrophobic bulk as for linear cationic antimicrobial peptides. Finally, the hemolytic activity of selected compounds was evaluated, which revealed a potential to produce active compounds with attenuation of unwanted hemolysis. The findings highlight the potential of cyclic cationic amphiphilic peptidomimetics as a class of promising compounds for the treatment of infections caused by microorganisms with an increased resistance to conventional antimicrobial agents.
Optimal design for resilient load‐sharing systems with nonidentical components
Authors: Xu Huyang , Fang Yuanchen , Fard Nasser 
Published: May 2018

AbstractFor system maintenance, strategic component restoration planning is an important conceptual framework for load‐sharing k‐out‐of‐n: G system. A cost‐effective treatment of failure events is imperative with the purpose of reinstating the system ability. This paper presents a new optimal design method for load‐sharing repairable k‐out‐of‐n: G system, in which a flowgraph is used in conjunction with multiresponse optimization. By introducing the concept of modular design, the system is partitioned into scalable and repairable maintenance modules. The determination of the optimal design depends on the type of system components, the module‐based system structure, and the repair rule setting. An extended flowgraph model, which links covariates into transition branches, is used for modeling the system failure evolution. With consideration of various system performance measurements as responses, multiresponse optimization with weighted principal component analysis is used to achieve an optimal design of maintenance modules as well as repair policy. The methodology presented in this paper provides an efficient way to design a system having nonidentical components and arbitrary repair time distributions with consideration of the variety of maintenance policies as well as the diversity of system operating conditions.
Characterization of alkylphosphonic acid vapors using atmospheric flow tube–ion trap mass spectrometry
Authors: Morrison Kelsey A. , Clowers Brian H. 
Published: May 2018

RationaleA key aspect of detecting hazardous compounds at ultra‐trace levels for processing, compliance, and clean‐up purposes involves developing methods that are not only sensitive, but also highly selective with minimal sampling effort. Atmospheric flow tube mass spectrometry (AFT‐MS) using dielectric barrier discharge ionization has emerged as a technique that combines such features for vapor detection. AFT‐MS is thus appealing for application to ambient screening for chemical warfare agents (CWAs) and their degradation products. Initial characterization of AFT‐MS for CWA detection necessitates examining less harmful simulant species. A predominant hydrolysis product of most organophosphorus CWAs is methylphosphonic acid and most other hydrolysis products consist of some form of an alkylphosphonic acid.MethodsAn application of AFT‐MS is presented wherein a homologous series of four alkylphosphonic acids (methyl‐, ethyl‐, propyl‐, and t‐butylphosphonic acid) were first qualitatively evaluated as anionic clusters with nitrate. These anionic adducts were subsequently quantified from non‐equilibrium headspace vapor sampled over alkylphosphonic acid solutions in methanol.ResultsThe series of phosphonic acids demonstrated consistent relative ion abundances thought to be related at least in part to the relative vapor pressures depending on their alkyl chains. For quantitation, the resulting linear ranges were found to be 2 to 50 ppmsoln for methylphosphonic acid, 5 to 50 ppmsoln for ethylphosphonic acid, and 2 to 25 ppmsoln for propylphosphonic acid and t‐butylphosphonic acid; quality controls of 15 ppmsoln were used to assess the quantitation accuracy.ConclusionsAlthough measured over a limited dynamic range, the real‐time analysis afforded by this method suggests the feasibility of using thermodynamically stable anionic adducts to monitor organophosphorus compounds via AFT‐MS. In addition, this is proof‐of‐concept for the use of this ambient sensing technique to detect phosphonic acids. Furthermore, a discussion is included regarding gaps in clustering thermodynamics literature that would assist in uncovering physical or chemical explanations for observed trends.
Robust fusion time‐varying Kalman estimators for multisensor networked systems with mixed uncertainties
Authors: Liu Wen‐Qiang , Wang Xue‐Mei , Deng Zi‐Li 
Published: May 2018

SummaryThis paper addresses the problem of designing robust fusion time‐varying Kalman estimators for a class of multisensor networked systems with mixed uncertainties including multiplicative noises, missing measurements, packet dropouts, and uncertain‐variance linearly correlated measurement and process white noises. By the augmented approach, the original system is converted into a stochastic parameter system with uncertain noise variances. Furthermore, applying the fictitious noise approach, the original system is converted into one with constant parameters and uncertain noise variances. According to the minimax robust estimation principle, based on the worst‐case system with the conservative upper bounds of the noise variances, the five robust fusion time‐varying Kalman estimators (predictor, filter, and smoother) are presented by using a unified design approach that the robust filter and smoother are designed based on the robust Kalman predictor, which include three robust weighted state fusion estimators with matrix weights, diagonal matrix weights, and scalar weights, a modified robust covariance intersection fusion estimator, and robust centralized fusion estimator. Their robustness is proved by using a combination method, which consists of Lyapunov equation approach, augmented noise approach, and decomposition approach of nonnegative definite matrix, such that their actual estimation error variances are guaranteed to have the corresponding minimal upper bounds for all admissible uncertainties. The accuracy relations among the robust local and fused time‐varying Kalman estimators are proved. A simulation example is shown with application to the continuous stirred tank reactor system to show the effectiveness and correctness of the proposed results.
Subsidies from anadromous sea lamprey (Petromyzon marinus) carcasses function as a reciprocal nutrient exchange between marine and freshwaters
Authors: Weaver D.M. , Coghlan S.M. , Greig H.S. , Klemmer A.J. , Perkins L.B. , Zydlewski J. 
Published: May 2018

AbstractNutrient and energy flows across ecosystem boundaries subsidize recipient communities and influence bottom‐up processes in food webs. Migratory fish such as anadromous sea lamprey provide a pulse of marine‐derived nutrients and energy to Atlantic coastal streams in spring when organisms would otherwise be subject to limiting resources. We conducted sea lamprey carcass addition experiments to characterize the role of subsidies on producer and consumer trophic pathways by manipulating subsidy quantity and light exposure. We demonstrated that producer and decomposer productivity is constrained by nutrients during spring; however, these limitations were reduced in producers as light limitations intensified through riparian shading. We observed no significant effects of increasing carcass subsidies on producer and decomposer biomass. Our results suggest that high densities of carcass subsidies may stimulate primary productivity; however, these effects are mediated by the degree of riparian shading, which demonstrated a onefold to fourfold difference in biomass accrual. In addition, sea lamprey carcass nutrients were captured by larval conspecifics. Stable isotopes analysis demonstrated that adult sea lamprey carcass tissue was relatively enriched in 15N and 13C isotopes compared with larvae. We observed significant enrichment in the 13C isotope among larvae sampled after 2 and 4 weeks of exposure to adult carcass nutrients. Our work suggests that a portion of sea lamprey subsidies serve as a reciprocal exchange between freshwaters and the ocean. We highlight that this cross‐ecosystem linkage is likely influenced by subsidy quantity from donor systems and is mediated by environmental characteristics affecting the recipient system.
A decision support system to diagnose factors limiting stream trout fisheries
Authors: Holmes R. , Matthaei C. , Gabrielsson R. , Closs G. , Hayes J. 
Published: May 2018

AbstractMaintaining or restoring productive freshwater fisheries is a key challenge for resource managers. However, the inherent uncertainty and complexity of managing fisheries, often based on scant environmental data, make it difficult for managers and the public to reach consensus on appropriate actions. To help deal with this issue, we created a literature‐based decision support system to diagnose limiting factors for stream brown trout fisheries. Once limiting factors are determined, appropriate management actions can be tailored to address them. Our Bayesian belief network (BBN)‐based framework serves 2 functions: (a) It directs users to assemble a parsimonious environmental data set to inform stream fishery management, and (b) it integrates and interrogates these data to generate standardized and testable hypotheses about which environment factors are likely to limit trout productivity. The BBN has been trained on brown trout because among freshwater fish, this species has the richest literature base and is highly valued worldwide. However, the framework could be adapted for other stream fish. We applied our BBN to the Horokiri Stream, a data‐rich catchment in Wellington, New Zealand. The BBN probability outputs were comparable with the conclusions of 5 experienced fishery biologists following their detailed investigation into the factors that led to the loss of the Horokiri brown trout fishery between 1951 and 1990.