bluuebunny/crossref_metadata_2025 huggingface dataset:
Control features of a four channel resonant buck converter
Authors: Litvani Lilla , Hamar Janos
Published: March 2019

This study presents the steady‐state behaviour of a new four channel resonant DC/DC buck converter in symmetrical operation both in continuous current conduction mode (CCM) and in discontinuous current conduction mode (DCM). Having two inputs and four outputs, one of the most important advantages of this converter is its capability to provide four identical or arbitrarily different output voltages, while power exchange between the input channels facilitates the smooth operation even when one of the inputs falls out (security power supply). The converter can be operated in zero‐current switching and zero‐voltage switching conditions that results in enhanced efficiency. The quasi‐sinusoidal waveforms help to lower electromagnetic interference. The analysis revealed the relations among input and output voltages as well as the effect of control variables on the steady‐state operation. The obtained theoretical results are verified by both computer simulations and measurements on a recently built experimental prototype. The analytical results and control characteristics are devoted to design such converters and develop control strategies for them.
Research Subjects and Research Trends in Medical Informatics
Authors: Gülkesen Kemal Hakan , Haux Reinhold
Published: March 2019

Objectives To identify major research subjects and trends in medical informatics research based on the current set of core medical informatics journals.

Methods Analyzing journals in the Web of Science (WoS) medical informatics category together with related categories from the years 2013 to 2017 by using a smart local moving algorithm as a clustering method for identifying the core set of journals. Text mining analysis with binary counting of abstracts from these journals published in the years 2006 to 2017 for identifying major research subjects. Building clusters based on these terms for the complete time period as well as for the periods 2006–2008, 2009–2011, 2012–2014, and 2015–2017 for identifying trends.

Results The identified cluster includes 17 core medical informatics journals. By text mining of these journals, 224,992 different terms in 14,414 articles were identified covering 550 specific key terms. Based on these key terms five clusters were identified: “Biomedical Data Analysis,” “Clinical Informatics,” “EHR and Knowledge Representation,” “Mobile Health,” and “Organizational Aspects of Health Information Systems.” No shifts in the clusters were observed between the first two 3-year periods. In the third period, some terms like “mobile phone,” “mobile apps,” and “message” appear. Also, in the third period, a “Clinical Informatics” cluster appears and persists in the fourth period. In the fourth period, a rearrangement of clusters was observed.

Conclusions Beside classical subjects of medical informatics on organizing, representing, and analyzing data, we observed new developments in the context of mobile health and clinical informatics. These subjects tended to grow over the past years, and we can expect this trend to continue.
Point-of-Care Mobile Application to Guide Health Care Professionals in Conducting Substance Use Screening and Intervention: A Mixed-Methods User Experience Study
Authors: O'Grady Megan , Kapoor Sandeep , Gilmer Evan , Neighbors Charles , Conigliaro Joseph , Kwon Nancy , Morgenstern Jon
Published: March 2019

Background Well-documented barriers have limited the widespread, sustained adoption of screening and intervention for substance use problems in health care settings. mHealth applications may address provider-related barriers; however, there is limited research on development and user experience of such applications.

Objective This user experience study examines a provider-focused point-of-care app for substance use screening and intervention in health care settings.

Method This mixed-methods study included think-aloud tasks, task success ratings, semistructured interviews, and usability questionnaires (e.g., System Usability Scale [SUS]) to examine user experience among 12 health coaches who provide substance use services in emergency department and primary care settings.

Results The average rate of successful task completion was 94% and the mean SUS score was 76 out of 100. Qualitative data suggested the app enhanced participants' capability to complete tasks efficiently and effectively. Participants reported being satisfied with the app's features, content, screen layout, and navigation and felt it was easy to learn and could benefit patient interactions. Despite overwhelmingly positive user experience reports, there were some concerns that the app could negatively affect patient interactions due to reductions in eye contact and ability to build rapport.

Conclusion Using the “Fit between Individuals, Task, and Technology” framework to guide interpretation, overall results indicate acceptable user experience and usability for this provider-focused point-of-care mobile app for substance use screening and intervention as well as favorable potential for adoption by health care practitioners. Such mobile health technologies may help to address well-known challenges related to implementing substance use services in health care settings.
Evaluation of RFID Technology to Capture Surgeon Arrival Time to Meet American College of Surgeons Committee on Trauma Verification Guidelines
Authors: Lyu Heather , Faoro Nicholas , McDonald Meghan , Jarman Molly , Kreitzman Kevin , Salim Ali , Landman Adam
Published: March 2019

Background The presence of an attending surgeon at all highest-level trauma activations is a requirement for American College of Surgeons-Committee on Trauma (ACS-COT) verification for level I to III trauma centers. Programs must demonstrate compliance with this criterion at least 80% of the time. Documentation of compliance can increase administrative burden presenting an opportunity for automation.

Objectives The aim of this quality improvement project was to compare surgeon arrival documentation rates obtained utilizing radio-frequency identification (RFID) technology with manual documentation.

Methods This project was conducted at a single level-I trauma center. RFID badges were distributed to all trauma surgeons. Arrival times for surgeons using manual nursing documentation and RFID activation were collected from October 2017 through March 2018. Presence of appropriate documentation and attending arrival within 15 minutes of trauma activation were compared by documentation method: nursing manual documentation or RFID system.

Results There were 98 code trauma activations included in the analysis over the 6-month period. Nursing documentation of trauma surgeon attendance occurred 83% of the time (n = 81), with 81% (n = 79) in compliance within 15 minutes of code trauma activation. RFID badges were activated 91% (n = 89) of the time, with 86% (n = 84) in compliance within 15 minutes. There was no statistically significant difference between the rates of nursing documentation and RFID badge activation.

Conclusion RFID technology is a reliable, complementary method of documenting compliance for trauma surgeon attendance. Trauma centers searching for technological solutions to address compliance with ACS-COT guidelines and to reduce administrative burden may consider the use of RFID technology.
Derivation of the 1d nonlinear Schrödinger equation from the 3d quantum many-body dynamics of strongly confined bosons
Authors: Boßmann Lea
Published: March 2019

We consider the dynamics of N interacting bosons initially exhibiting Bose–Einstein condensation. Due to an external trapping potential, the bosons are strongly confined in two spatial directions, with the transverse extension of the trap being of order ε. The non-negative interaction potential is scaled such that its scattering length is positive and of order (N/ε2)−1 and the range of the interaction scales as (N/ε2)−β for β ∈ (0, 1). We prove that in the simultaneous limit N → ∞ and ε → 0, the condensation is preserved by the dynamics and the time evolution is asymptotically described by a cubic defocusing nonlinear Schrödinger equation in one dimension, where the strength of the nonlinearity depends on the interaction and on the confining potential. This is the first derivation of a lower-dimensional effective evolution equation for singular potentials scaling with β≥12 and lays the foundations for the derivation of the physically relevant one-dimensional Gross–Pitaevskii equation (β = 1). For our analysis, we adapt an approach by Pickl to the problem with strong confinement.
Theory of applying shear strains from boundary walls: Linear response in glasses
Authors: Onuki Akira , Kawasaki Takeshi
Published: March 2019

We construct a linear response theory of applying shear deformations from boundary walls in the film geometry in Kubo’s theoretical scheme. Our method is applicable to any solids and fluids. For glasses, we assume quasi-equilibrium around a fixed inherent state. Then, we obtain linear-response expressions for any variables including the stress and the particle displacements, even though the glass interior is elastically inhomogeneous. In particular, the shear modulus can be expressed in terms of the correlations between the interior stress and the forces from the walls. It can also be expressed in terms of the inter-particle correlations, as has been shown in the previous literature. Our stress relaxation function includes the effect of the boundary walls and can be used for inhomogeneous flow response. We show the presence of long-ranged, long-lived correlations among the fluctuations of the forces from the walls and the displacements of all the particles in the cell. We confirm these theoretical results numerically in a two-dimensional model glass. As an application, we describe emission and propagation of transverse sounds after boundary wall motions using these time-correlation functions. We also find resonant sound amplification when the frequency of an oscillatory shear approaches that of the first transverse sound mode.
A generalized vibronic-coupling Hamiltonian for molecules without symmetry: Application to the photoisomerization of benzopyran
Authors: Gonon Benjamin , Lasorne Benjamin , Karras Gabriel , Joubert-Doriol Loïc , Lauvergnat David , Billard Franck , Lavorel Bruno , Faucher Olivier , Guérin Stéphane , Hertz Edouard , Gatti Fabien
Published: March 2019

We present a model for the lowest two potential energy surfaces (PESs) that describe the photoinduced ring-opening reaction of benzopyran taken as a model compound to study the photochromic ring-opening reaction of indolinobenzospiropyran and its evolution toward its open-chain analog. The PESs are expressed in terms of three effective rectilinear coordinates. One corresponds to the direction between the equilibrium geometry in the electronic ground state, referred to as the Franck-Condon geometry, and the minimum of conical intersection (CI), while the other two span the two-dimensional branching space at the CI. The model correctly reproduces the topography of the PESs. The ab initio calculations are performed with the extended multiconfiguration quasidegenerate perturbation theory at second order method. We demonstrate that accounting for electron dynamic correlation drastically changes the global energy landscape since some zwitterionic states become strongly stabilized. Quantum dynamics calculations using this PES model produce an absorption spectrum that matches the experimental one to a good accuracy.
Fast dynamics of a hydrogen-bonding glass forming liquid: Chemical exchange-induced spectral diffusion in 2D IR spectroscopy
Authors: Hoffman David J. , Fica-Contreras Sebastian M. , Fayer Michael D.
Published: March 2019

Polarization-selective Two Dimensional Infrared (2D IR) and IR pump-probe spectroscopies have been performed on the hydrogen bonding glass forming liquid 2-biphenylmethanol doped with the long-lived vibrational probe phenylselenocyanate over a wide range of temperatures. The spectral diffusion seen in the 2D spectra was found to have a large polarization dependence, in large excess of what is predicted by standard theory. This anomaly was explained by decomposing the 2D spectra into hydrogen-bonding and non-bonding components, which exchange through large-angle orientational motion. By adapting chemical exchange theories, parameters for the component peaks were then calculated by fitting the polarization-dependent spectral diffusion and the pump-probe anisotropy. A model of highly heterogeneous exchange and orientational dynamics was used to explain the observed time dependences as a function of temperature on fast time scales. The experimental observations, the kinetic modeling, and physical arguments lead to the determination of the times for interconversion of slow dynamics structural domains to fast dynamics structural domains in the supercooled liquid as a function of temperature. The slow to fast domain interconversion times range from 40 ps at 355 K to 5000 ps at 270 K.
Learning from aspen leaves how to harvest energy from the slightest breeze
Authors: Kim Meeri
Published: March 2019

A new article reports on an aeroelastic energy harvester inspired by trembling aspen leaves, which are known to quiver in the presence of the slightest breeze.
Clinical requirements for extracellular vesicle assays
Authors: Ayers Lisa , Pink Ryan , Carter David Raul Francisco , Nieuwland Rienk
Published: March 2019

The scientific and clinical interest in extracellular vesicles (EV) has grown exponentially during the past 15 years. As most research indicates that EVs can be utilised in diagnostics, prognostics and therapeutics, we may be on the brink of establishing the clinical utility of EV measurement, but how can we make this a reality? If we are to introduce EVs as biomarkers into clinical laboratories, it will be necessary to offer fully validated, International Organization for Standardization (ISO) standard 15189 assays. ISO 15189 defines the quality management system requirements particular to medical laboratories and is used internationally to determine accreditation. In order for a clinical laboratory to offer an accredited test for EVs, this assay must have been subjected to a thorough assay validation process. This process requires the generation of data related to defined performance characteristics, to ensure that an assay is performing in accordance with the needs of its clinical users. Each of the defined performance characteristics will be discussed in this review, along with the issues that specifically affect EV analysis. Accreditation is increasingly important for all clinical laboratories and the standards required to achieve this are becoming more and more stringent. Therefore, as companies seek to develop the best assays to detect EVs and their molecular contents for clinical utility, and as we move rapidly towards our goal of offering EV analysis in the diagnosis and monitoring of disease, it is timely to highlight the requirements for the clinical accreditation of such assays. It is essential to consider these parameters to ensure that we develop the highest quality assays possible and ultimately the best outcomes for patients.
An approach to the development of comparative cross-national studies of street-level bureaucracy
Authors: Hill Michael , Møller Marie Østergaard
Published: March 2019

Propositions about street-level bureaucracy run the risk of violating the scientific precept that a theoretical generalisation should be tested by replication in a variety of contexts. Many examples can be found of writings that simply indicate that street-level discretion is pervasive. This prompts the questions, ‘but how’, and under what conditions ‘may’ that happen? Comparison is needed to answer these questions, particularly cross-national ones. It will be argued that good cross-national comparative work must rest upon precise specification of the contexts to be compared and avoiding comparing tasks that seem similar, but in fact serve different functions in different contexts. To explore this one particular task – pre-school child care – is selected. The discussion of this specific example is examined as a model for similar comparative work.
Origin and formation process of a submerged vortex in a pump sump
Authors: Yamade Y , Kato C , Nagahara T , Matsui Jun
Published: March 2019

The origin and formation process of a submerged vortex have been fully clarified by large-eddy simulation (LES) that used approximately of 250 million hexahedral elements with maximum resolution of 0.450 mm and was applied to the internal flows of a model pump sump. The model pump sump is composed of a 2,500 mm-long water channel of rectangular cross section with a width of 300 mm and a water depth of 100 mm and a vertical suction pipe with a 100 mm diameter installed at its downstream end. At the upstream end of the channel, a uniform velocity of 0.37 m/s is given. LES with different wall boundary conditions have revealed that the origin of a submerged vortex is the mean shear of the approaching boundary layers that develop on the bottom and side walls of the pump sump. Detailed investigations of LES computed for a long time period of 16 seconds have revealed that deviation of the mean flow that approaches the suction pipe triggers conversion of the axis of the vorticity that was originally aligned to the lateral direction in the approaching boundary layers to that aligned to the vertical direction. The local acceleration of the vertical flow stretches the afore-mentioned vertical vortex, which results in the formation of a strong submerged vortex. A computation with a different height of the vermouth inlet has supported the above mentioned formation process of a submerged vortex.
On the computability of perfect subsets of sets with positive measure
Authors: Chong C. , Li Wei , Wang Wei , Yang Yue
Published: March 2019

A set

X
⊆

2
ω

X \subseteq 2^\omega

with positive measure contains a perfect subset. We study such perfect subsets from the viewpoint of computability and prove that these sets can have weak computational strength. Then we connect the existence of perfect subsets of sets with positive measure with reverse mathematics.
No topological condition implies equality of polynomial and rational hulls
Authors: Izzo Alexander
Published: March 2019

It is shown that no purely topological condition implies the equality of the polynomial and rational hulls of a set: For any uncountable, compact subset

K
K

of a Euclidean space, there exists a set

X
X

, in some

C

N

\mathbb {C}^N

, that is homeomorphic to

K
K

and is rationally convex but not polynomially convex. In addition, it is shown that for the surfaces in

C

3

\mathbb {C}^3

constructed by Izzo and Stout, whose polynomial hulls are nontrivial but contain no analytic discs, the polynomial and rational hulls coincide, thereby answering a question of Gupta. Equality of polynomial and rational hulls is shown also for

m
m

-dimensional manifolds (

m
≥
2

m\geq 2

) with polynomial hulls containing no analytic discs constructed by Izzo, Samuelsson Kalm, and Wold and by Arosio and Wold.
Networked robust stability for linear time-varying systems
Authors: Yu Tianqiu
Published: March 2019

A networked control system (NCS) with the communication channels described by cascaded two-port networks for linear time-varying systems is studied. In this framework, a system is considered as a (possibly unbounded) linear operator that maps an input space to an output space. We consider the operator norm bounded uncertainties in the transmission matrices of two-port networks as well as the gap-type uncertainties in the plant and controller. A necessary and sufficient condition for robust stability of the NCS is generalized from the time-invariant case.
Characterizing Short-Term Jobs in a Population-Based Study
Authors: Parent Marie-Élise , Richard Hugues , Sauvé Jean-François
Published: March 2019

Background

Work histories generally cover all jobs held for ≥1 year. However, it may be time and cost prohibitive to conduct a detailed exposure assessment for each such job. While disregarding short-term jobs can reduce the assessment burden, this can be problematic if those jobs contribute important exposure information towards understanding disease aetiology.

Objective

To characterize short-term jobs, defined as lasting more than 1 year, but less than 2 years, in a population-based study conducted in Montreal, Canada.

Methods

In 2005–2012, we collected work histories for some 4000 participants in a case-control study of prostate cancer. Overall, subjects had held 19 462 paid jobs lasting ≥1 year, including 3655 short-term jobs. Using information from interviews and from the Canadian Classification and Dictionary of Occupations, we characterized short-term jobs and compared them to jobs held ≥2 years.

Results

Short-term jobs represented <4% of subjects’ work years on average. Forty-five per cent of subjects had at least one short-term job; of these, 49% had one, 24% had two, and 27% had at least three. Half of all short-term jobs had been held before the age of 24. Short-term jobs entailed more often exposure to fumes, odours, dust, and/or poor ventilation than longer jobs (17 versus 13%), as well as outdoor work (10 versus 5%) and heavy physical activity (16 versus 12%).

Conclusions

Short-term jobs occurred often in early careers and more frequently entailed potentially hazardous exposures than longer-held jobs. However, as they represented a small proportion of work years, excluding them should have a marginal impact on lifetime exposure assessment.
A new biological species in the Mercurialis annua polyploid complex: functional divergence in inflorescence morphology and hybrid sterility
Authors: Ma Wen-Juan , Santos del Blanco Luis , Pannell John R
Published: March 2019

Background and Aims

Polyploidy has played a major role in the origin of new plant species, probably because of the expansion of polyploid populations in the species’ ecological niche, and because reproductive isolation can be established between a new polyploid population and its diploid progenitor species. It is well established that most polyploid species are polyphyletic, with multiple independent origins, and that polyploid genomes may undergo rapid change after their duplication and hybridization associated with their origin. We considered whether multiple independent origins and rapid genomic change might lead to reproductive isolation between polyploid populations of the same ploidy but with potentially different evolutionary histories.

Methods

We tested our hypothesis by assessing differences in DNA content and morphology, the evolution of reproductive isolation, and the phylogenetic placement of two broadly sympatric hexaploid lineages of the wind-pollinated annual plant Mercurialis annua hitherto regarded as populations of the same species.

Key Results

The two hexaploid lineages of M. annua have slightly divergent DNA content, and distinct inflorescence morphology. They also fall into largely different clades of a chloroplast phylogeny and are reproductively isolated from one another.

Conclusions

The distinct evolutionary histories of the two hexaploid lineages of M. annua have contributed to the remarkable reproductive diversity of the species complex. It seems likely that reproductive interference between them will eventually lead to the displacement of one lineage by the other via pollen swamping. Thus, whereas polyploidization can contribute to speciation, diversification might also be compromised by reproductive interference.
Dynamic Prediction of Death in Patients With Tuberculous Meningitis Using Time-updated Glasgow Coma Scale and Plasma Sodium Measurements
Authors: Thao Le Thi Phuong , Wolbers Marcel , Heemskerk A Dorothee , Thi Hoang Mai Nguyen , Thi Minh Ha Dang , Thi Hong Chau Tran , Hoan Phu Nguyen , Van Vinh Chau Nguyen , Caws Maxine , Huu Lan Nguyen , Dang Anh Thu Do , Thuy Thuong Thuong Nguyen , Day Jeremy , Torok M Estee , Duc Bang Nguyen , Thwaites Guy E , Geskus Ronald B
Published: March 2019

Background

Pretreatment predictors of death from tuberculous meningitis (TBM) are well established, but whether outcome can be predicted more accurately after the start of treatment by updated clinical variables is unknown. Hence, we developed and validated models that dynamically predict mortality using time-updated Glasgow Coma Scale (GCS) and plasma sodium measurements, together with patient baseline characteristics.

Methods

We included 1048 adults from 4 TBM studies conducted in southern Vietnam from 2004 to 2016. We used a landmarking approach to predict death within 120 days after treatment initiation using time-updated data during the first 30 days of treatment. Separate models were built for patients with and without human immunodeficiency virus (HIV) infection. We used the area under the receiver operating characteristic curve (AUC) to evaluate performance of the models at days 10, 20, and 30 of treatment to predict mortality by 60, 90, and 120 days. Our internal validation was corrected for overoptimism using bootstrap. We provide a web-based application that computes mortality risk within 120 days.

Results

Higher GCS indicated better prognosis in all patients. In HIV-infected patients, higher plasma sodium was uniformly associated with good prognosis, whereas in HIV-uninfected patients the association was heterogeneous over time. The bias-corrected AUC of the models ranged from 0.82 to 0.92 and 0.81 to 0.85 in HIV-uninfected and HIV-infected individuals, respectively. The models outperformed the previously published baseline models.

Conclusions

Time-updated GCS and plasma sodium measurements improved predictions based solely on information obtained at diagnosis. Our models may be used in practice to define those with poor prognosis during treatment.
A Multiple-Layer Machine Learning Architecture for Improved Accuracy in Sentiment Analysis
Authors: Shyamasundar L B , Jhansi Rani P
Published: March 2019

Twitter is an online micro-blogging platform through which one can explore the hidden valuable and delightful information about the current context at any point of time, which also serves as a data source to carry out sentiment analysis. In this paper, the sentiments of large amount of tweets generated from Twitter in the form of big data have been analyzed using machine learning algorithms. A multi-tier architecture for sentiment classification is proposed in this paper, which includes modules such as tokenization, data cleaning, preprocessing, stemming, updated lexicon, stopwords and emoticon dictionaries, feature selection and machine learning classifier. Unigram and bigrams have been used as feature extractors together with χ2 (Chi-squared) and Singular Value Decomposition for dimensionality reduction together with two model types (Binary and Reg), with four types of scaling methods (No scaling, Standard, Signed and Unsigned) and represented them in three different vector formats (TF-IDF, Binary and Int). Accuracy is considered as the evaluation standard for random forest and bagged trees classification methods. Sentiments were analyzed through tokenization and having several stages of pre-processing and several combinations of feature vectors and classification methods. Through which it was possible to achieve an accuracy of 84.14%. Obtained results conclude that, the proposed scheme gives a better accuracy when compared with existing schemes in the literature.
Short-term preoperative protein restriction attenuates vein graft disease via induction of cystathionine γ-lyase
Authors: Trocha Kaspar M , Kip Peter , Tao Ming , MacArthur Michael R , Treviño-Villarreal J Humberto , Longchamp Alban , Toussaint Wendy , Lambrecht Bart N , de Vries Margreet R , Quax Paul H A , Mitchell James R , Ozaki C Keith
Published: March 2019

Aims

Therapies to prevent vein graft disease, a major problem in cardiovascular and lower extremity bypass surgeries, are currently lacking. Short-term preoperative protein restriction holds promise as an effective preconditioning method against surgical stress in rodent models, but whether it can improve vein graft patency after bypass surgery is undetermined. Here, we hypothesized that short-term protein restriction would limit vein graft disease via up-regulation of cystathionine γ-lyase and increased endogenous production of the cytoprotective gaseous signalling molecule hydrogen sulfide.

Methods and results

Low-density lipoprotein receptor knockout mice were preconditioned for 1 week on a high-fat high-cholesterol (HFHC) diet with or without protein prior to left common carotid interposition vein graft surgery with caval veins from donor mice on corresponding diets. Both groups were returned to a complete HFHC diet post-operatively, and vein grafts analysed 4 or 28 days later. A novel global transgenic cystathionine γ-lyase overexpressing mouse model was also employed to study effects of genetic overexpression on graft patency. Protein restriction decreased vein graft intimal/media+adventitia area and thickness ratios and intimal smooth muscle cell infiltration 28 days post-operatively, and neutrophil transmigration 4 days post-operatively. Protein restriction increased cystathionine γ-lyase protein expression in aortic and caval vein endothelial cells (ECs) and frequency of lung EC producing hydrogen sulfide. The cystathionine γ-lyase inhibitor propargylglycine abrogated protein restriction-mediated protection from graft failure and the increase in hydrogen sulfide-producing ECs, while cystathionine γ-lyase transgenic mice displayed increased hydrogen sulfide production capacity and were protected from vein graft disease independent of diet.

Conclusion

One week of protein restriction attenuates vein graft disease via increased cystathionine γ-lyase expression and hydrogen sulfide production, and decreased early inflammation. Dietary or pharmacological interventions to increase cystathionine γ-lyase or hydrogen sulfide may thus serve as new and practical strategies to improve vein graft durability.
High Adherence to Surveillance Guidelines in Inflammatory Bowel Disease Patients Results in Low Colorectal Cancer and Dysplasia Rates, While Rates of Dysplasia are Low Before the Suggested Onset of Surveillance
Authors: Singh Kelita , Al Khoury Alex , Kurti Zsuzsanna , Gonczi Lorant , Reinglas Jason , Verdon Christine , Kohen Rita , Bessissow Talat , Afif Waqqas , Wild Gary , Seidman Ernest , Bitton Alain , Lakatos Peter L
Published: March 2019

Background

Patients with Crohn’s disease [CD] and ulcerative colitis [UC] are at increased risk for colorectal dysplasia [CRD] and colorectal cancer [CRC]. Adherence to CRC surveillance guidelines is reportedly low internationally.

Aim

To evaluate surveillance practices at the tertiary IBD Center of the McGill University Health Center [MUHC] and to determine CRD/CRC incidence.

Methods

A representative inflammatory bowel disease cohort with at least 8 years of disease duration [or with primary sclerosing cholangitis] who visited the MUHC between July 1 and December 31, 2016 were included. Adherence to surveillance guidelines was compared to modified 2010 British Society of Gastroenterology guidelines. Incidence rates of CRC, high-grade dysplasia [HGD], low-grade dysplasia [LGD] and colorectal adenomas [CRA] were calculated based on pathology.

Results

In total, 1356 CD and UC patients (disease duration: 12 [interquartile range: 6–22) and 10 [interquartile range: 5–19] years) were identified. The surveillance cohort consisted of 680 patients [296 UC and 384 CD]. Adherence to surveillance guidelines was 76/82% in UC/colonic CD. An adequate number of biopsies were taken in 54/54% of UC/colonic CD patients. The incidence of CRC/HGD in UC and CD with colonic involvement was 19.5/58.5 and 25.1/37.6 per 100,000 patient-years, respectively. The incidence of dysplasia before 8 years of disease duration was low in both UC/CD [19.5 and 12.5/100,000 patient-years] with no CRC detected. The CRA rate was 30/38% in UC/colonic CD.

Conclusion

High adherence to surveillance guidelines and low CRC and dysplasia, but not CRA rates were found, suggesting that adhering to updated, stratified, surveillance recommendations may result in low advanced neoplasia rates. The incidence of dysplasia before the start of surveillance was low.
Cardiovascular manifestations of sickle cell disease
Authors: Hammoudi Nadjib , Lionnet François , Redheuil Alban , Montalescot Gilles
Published: March 2019

Sickle cell disease (SCD) is the most frequent genetic haemoglobinopathy worldwide. Early childhood mortality has dramatically decreased in high-income countries, and most patients now survive beyond the 5th decade. However, in the aging SCD population, the morbidity related to chronic organ damage, especially kidney and heart, has become a major concern. While pulmonary hypertension has attracted most attention, it appears that this condition is frequently linked to left heart failure (HF). Accordingly, SCD-associated cardiomyopathy is emerging as a major cause of reduced quality of life and early mortality in these patients. The diagnosis of this particular phenotype of high-output HF is challenging. Exercise intolerance and dyspnoea in SCD patients are linked to multiple causes including chronic anaemia. Moreover, echocardiographic features are unusual and can be misinterpreted. The classical diagnosis algorithm for HF is generally not suitable in SCD patients, and HF is poorly recognized and mostly diagnosed at a late congestive stage in routine practice. Such patients need to be identified at an earlier stage of myocardial dysfunction via improved phenotyping. This constitutes the first step towards further investigations in SCD needed to improve the prognosis and the quality of life. This article provides an updated review of the recent advances in the pathophysiology and diagnosis, and in addition, perspectives of new therapeutic approaches in SCD-related cardiac manifestations.
Molecular and genetic insights into progressive cardiac conduction disease
Authors: Asatryan Babken , Medeiros-Domingo Argelia
Published: March 2019

Progressive cardiac conduction disease (PCCD) is often a primarily genetic disorder, with clinical and genetic overlaps with other inherited cardiac and metabolic diseases. A number of genes have been implicated in PCCD pathogenesis with or without structural heart disease or systemic manifestations. Precise genetic diagnosis contributes to risk stratification, better selection of specific therapy and allows familiar cascade screening. Cardiologists should be aware of the different phenotypes emerging from different gene-mutations and the potential risk of sudden cardiac death. Genetic forms of PCCD often overlap or coexist with other inherited heart diseases or manifest in the context of multisystem syndromes. Despite the significant advances in the knowledge of the genetic architecture of PCCD and overlapping diseases, in a measurable fraction of PCCD cases, including in familial clustering of disease, investigations of known cardiac disease-associated genes fail to reveal the underlying substrate, suggesting that new causal genes are yet to be discovered. Here, we provide insight into genetics and molecular mechanisms of PCCD and related diseases. We also highlight the phenotypic overlaps of PCCD with other inherited cardiac and metabolic diseases, present unmet challenges in clinical practice, and summarize the available therapeutic options for affected patients.
Effects of Childhood-onset Inflammatory Bowel Disease on School Performance: A Nationwide Population-based Cohort Study Using Swedish Health and Educational Registers
Authors: Malmborg Petter , Mouratidou Natalia , Sachs Michael C , Hammar Ulf , Khalili Hamed , Neovius Martin , Hjern Anders , Smedby Karin E , Ekbom Anders , Askling Johan , Ludvigsson Jonas F , Olén Ola
Published: March 2019

Background

Childhood-onset inflammatory bowel disease (IBD) might negatively impact academic school performance. We conducted a nationwide study to examine the association between childhood-onset IBD and school results.

Methods

Our study population was selected from Swedish health registers. In the National Patient Register (1990 to 2013), we identified 2827 children with IBD: Crohn’s disease (CD), n = 1207, and ulcerative colitis (UC), n = 1370. Patients were matched with 10 reference individuals by age, sex, birth year, and place of residence (n = 28,235). Final compulsory school grades (0 to 320 grade points) and qualification for high school (yes or no) were obtained through the National School Register. Regression models controlling for socioeconomic factors were used to analyze the association of IBD with school performance.

Results

Children with IBD had a lower final grade point average (adjusted mean grade difference [AMGD] −4.9, 95% confidence interval [CI] −7.1 to −2.6) but not a significantly higher risk to not qualify for high school (odds ratio [OR] 1.14, CI 0.99–1.31). The results were similar in children with UC (AMGD −5.5, CI −8.7 to −2.3) and CD (AMGD −4.7, CI −8.2 to −1.2). Underperformance was more common in subsets of IBD children characterized by markers associated with long-standing active disease (eg, >30 inpatient days [AMGD−18.1, CI −25.8 to −10.4]).

Conclusion

Most children with IBD achieve comparable results in the final year of compulsory school as their healthy peers. Care should be improved for the subgroup of children for which IBD has a stronger negative impact on school performance.
Same Principles but Different Purposes: Passive Fluid Handling throughout the Animal Kingdom
Authors: Joel Anna-Christin , Weissbach Margret
Published: March 2019

Everything on earth is subject to physical laws, thus they influence all facets of living creatures. Although these laws restrain animals in many ways, some animals have developed a way to use physical phenomena in their favor to conserve energy. Many animals, which have to handle fluids, for example, have evolved passive mechanisms by adapting their wettability or using capillary forces for rapid fluid spreading. In distinct animals, a similar selection pressure always favors a convergent development. However, when assessing the biological tasks of passive fluid handling mechanisms, their diversity is rather surprising. Besides the well-described handling of water to facilitate drinking in arid regions, observed in, e.g., several lizards, other animals like a special flat bug have developed a similar mechanism for a completely different task and fluid: Instead of water, these bugs passively transport an oily defense secretion to a region close to their head where it finally evaporates. And again some spiders use capillary forces to capture prey, by sucking in the viscous waxy cuticle of their prey with their nanofibrous threads. This review highlights the similarities and differences in the deployed mechanisms of passive fluid handling across the animal kingdom. Besides including well-studied animals to point out different mechanisms in general, we stretch over to not as extensively studied species for which similar mechanisms are described for different tasks. Thus, we provide an extensive overview of animals for which passive fluid handling is described so far as well as for future inspiration.
The journey from theory to practice in the field of competition law
Authors: Dabbah Eyad Maher M
Published: March 2019

This article considers the important relationship between law and economics in the field of competition law. The article shows how economics has become a dominant discipline in the field and the difficulties this development has given, and is likely to give, rise to in practice. In doing so, the article considers the heavy reliance which lawyers in particular have come to place on economics. The article offers a number of illustrations taken from different areas of competition law and policy in order to support the analysis and arguments therein. The article offers a perspective on what the exact relationship between law and economics should be and what role lawyers should play in order to facilitate a smooth transition from theory to practice and ultimately ensure that competition law is developed and applied correctly and in a way that matches the realities of markets and the business world.
Oviposition Behavior of Culex annulirostris (Diptera: Culicidae) Is Affected by the Recent Presence of Invasive Gambusia holbrooki (Cyprinodontiformes: Poeciliidae)
Authors: Hanford Jayne K , Hochuli Dieter F , Webb Cameron E
Published: March 2019

Constructed wetlands are popular tools for managing threatened flora and fauna in urban settings, but there are concerns that these habitats may increase mosquito populations and mosquito-related public health risks. Understanding the interactions occurring between mosquitoes of public health concern and co-occurring organisms is critical to informing management of these habitats to mitigate potential health risks and balance the multiple values of urban wetlands. This study examined how oviposition behavior of Culex annulirostris Skuse, the most important pest mosquito species associated with freshwater wetland habitats in Australia, is influenced by the presence of Gambusia holbrooki Girard, a widespread invasive fish. Water was collected from urban wetlands that are intensively managed to reduce G. holbrooki populations to assist conservation of locally threatened frogs, and adjacent unmanaged wetlands where G. holbrooki was abundant. Laboratory experiments were conducted to examine the oviposition response by Cx. annulirostris to water samples from these two habitats. Experiments were conducted on two occasions, once in February following draining and refilling of the urban wetlands, and repeated following a substantial rainfall event in March. The results clearly demonstrate that ovipositing mosquitoes were able to detect and avoid water derived from habitats containing fish, even in the absence of the fish themselves. Understanding how invasive species affect the behavior and spatial distribution of pest species such as Cx. annulirostris will enable future wetland design and management to maximize benefits of urban wetlands and minimize potential public health risks.
Association of Indoor Tanning Exposure With Age at Melanoma Diagnosis and BRAF V600E Mutations
Authors: Burbidge Toni E , Bastian Boris C , Guo Danny , Li Haocheng , Morris Don G , Monzon Jose G , Leung Gabriella , Yang Huiming , Cheng Tina
Published: March 2019

There is limited information on how indoor tanning promotes melanoma development. We investigated indoor tanning use in patients with melanomas in sun-exposed skin and studied the clinicopathological and molecular characteristics in relation to indoor tanning exposure. Patients from a multidisciplinary clinic for cutaneous cancers completed standardized questionnaires on risk factors for melanoma as a component of medical history at their initial consultations. For this study, we included patients from December 2013 to May 2015. The 114 patients who reported indoor tanning exposure were younger at diagnosis than the 222 patients who did not (51.5 vs 64.0 years, two-sided P < .001). BRAF V600E genotype was more prevalent in ever-users than in nonusers (42.9% vs 28.3%, two-sided P = .04) and higher in ever-users who initiated indoor tanning prior to age 25 years compared with age 25 years or older (62.2% vs 31.1%, two-sided P = .003). There were more melanomas in intermittently sun-exposed skin in ever-users than nonusers (65.7% vs 51.9%, respectively, two-sided P = .02). Our data suggest indoor tanning may promote melanomas that arise in skin with low-chronic sun-induced damage through BRAF V600E-mediated melanomagenesis.
Urca reactions during neutron star inspiral
Authors: Arras Phil , Weinberg Nevin N
Published: March 2019

We study the impact of Urca reactions driven by tidally induced fluid motion during binary neutron star inspiral. Fluid compression is computed for low radial order oscillation modes through an adiabatic, time-dependent solution for the mode amplitudes. Optically thin neutrino emission and heating rates are then computed from this adiabatic fluid motion. Calculations use direct and modified Urca reactions operating in a $M=1.4\, \mathrm{ M}_\odot$ neutron star, which is constructed using the Skyrme Rs equation of state. We find that the energy pumped into low-order oscillation modes is not efficiently thermalized even by direct Urca reactions, with core temperatures reaching only T ≃ 108 K during the inspiral. Although this is an order of magnitude larger than the heating due to shear viscosity considered by previous studies, it reinforces the result that the stars are quite cold at merger. Upon excitation of the lowest order g mode, the chemical potential imbalance reaches $\beta \gtrsim 1\, \rm MeV$ at orbital frequencies $\nu _{\rm orb} \gtrsim 200\, \rm Hz$, implying significant charged-current optical depths and Fermi-blocking. To assess the importance of neutrino degeneracy effects, the neutrino transfer equation is solved in the static approximation for the three-dimensional density distribution, and the reaction rates are then computed including Fermi-blocking. We find that the heating rate is suppressed by a factor of a ∼2 for $\nu _{\rm orb} \gtrsim 200\, \rm Hz$. The spectrum of emitted νe and $\bar{\nu }_e$, including radiation transfer effects, is presented for a range of orbital separations.
A luminosity distribution for kilonovae based on short gamma-ray burst afterglows
Authors: Ascenzi Stefano , Coughlin Michael W , Dietrich Tim , Foley Ryan J , Ramirez-Ruiz Enrico , Piranomonte Silvia , Mockler Brenna , Murguia-Berthier Ariadna , Fryer Chris L , Lloyd-Ronning Nicole M , Rosswog Stephan
Published: March 2019

The combined detection of a gravitational-wave signal, kilonova, and short gamma-ray burst (sGRB) from GW170817 marked a scientific breakthrough in the field of multimessenger astronomy. But even before GW170817, there have been a number of sGRBs with possible associated kilonova detections. In this work, we re-examine these ‘historical’ sGRB afterglows with a combination of state-of-the-art afterglow and kilonova models. This allows us to include optical/near-infrared synchrotron emission produced by the sGRB as well as ultraviolet/optical/near-infrared emission powered by the radioactive decay of r-process elements (i.e. the kilonova). Fitting the light curves, we derive the velocity and the mass distribution as well as the composition of the ejected material. The posteriors on kilonova parameters obtained from the fit were turned into distributions for the peak magnitude of the kilonova emission in different bands and the time at which this peak occurs. From the sGRB with an associated kilonova, we found that the peak magnitude in H bands falls in the range [−16.2, −13.1] ($95{{\ \rm per\ cent}}$ of confidence) and occurs within $0.8\!-\!3.6\, \rm d$ after the sGRB prompt emission. In g band instead we obtain a peak magnitude in range [−16.8, −12.3] occurring within the first 18 h after the sGRB prompt. From the luminosity distributions of GW170817/AT2017gfo, kilonova candidates GRB130603B, GRB050709, and GRB060614 (with the possible inclusion of GRB150101B, GRB050724A, GRB061201, GRB080905A, GRB150424A, and GRB160821B) and the upper limits from all the other sGRBs not associated with any kilonova detection we obtain for the first time a kilonova luminosity distribution in different bands.