bluuebunny/crossref_metadata_2025_split huggingface dataset:
Robust quantitative contrast‐enhanced dual‐energy CT for radiotherapy applications
Authors: Lapointe Andréanne , Lalonde Arthur , Bahig Houda , Carrier Jean‐François , Bedwani Stéphane , Bouchard Hugo 
Published: April 2018

PurposeThe purpose of this study was to develop and validate accurate methods for determining iodine content and virtual noncontrast maps of physical parameters, such as electron density, in the context of radiotherapy.MethodsA simulation environment is developed to compare three methods allowing extracting iodine content and virtual noncontrast composition: (a) two‐material decomposition, (b) three‐material decomposition with the conservation of volume constraint, and (c) eigentissue decomposition. The simulation allows comparing the performance of the methods using iodine‐based contrast agent contents in tissues from a reference dataset with variable density and elemental composition. The comparison is performed in two ways: (a) with a priori knowledge on the composition of the targeted tissue, and (b) without a priori knowledge on the base tissue. The three methods are tested with patient images scanned with dual‐energy CT and iodine‐based contrast agent. An experimental calibration adapted to the presence of iodine is performed by imaging tissue equivalent materials and diluted contrast agent solutions with known atomic composition.ResultsResults show that in the case of known a priori on the composition of the targeted tissue, the two‐material decomposition is robust to variable densities and atomic compositions without biasing the results. In the absence of a priori knowledge on the target tissue composition, the eigentissue decomposition method yields minimal bias and higher robustness to variations. Results from the experimental calibration and the images of two patients show that the extracted quantities are accurate and the bias is negligible for both methods with respect to clinical applications in their respective scope of use. For the patient imaged with a contrast agent, virtual noncontrast electron densities are found in good agreement with values extracted from the scan without contrast agent.ConclusionThis study identifies two accurate methods to quantify iodine‐based contrast agents and virtual noncontrast composition images with dual‐energy CT. One is the two‐material decomposition with a priori knowledge of the constituent components focused on organ‐specific applications, such as kidney or lung function assessment. The other method is the eigentissue decomposition and is useful for general radiotherapy applications, such as treatment planning where accurate dose calculations are needed in the absence of contrast agent.
Dielectric spectroscopy of nanocomposites based on iPP and aPS treated in the water solutions of alkali metal salts
Authors: Petronijevic Ivan M. , Cerovic Dragana D. , Dudic Dusko A. , Dojcilovic Jablan R. , Dojcinovic Biljana P. , Pergal Marija V. 
Published: April 2018

In this paper, a new simple and environmentally friendly treatment technique for obtaining polymer nanocomposites with appropriate dielectric properties has been presented. Sheets of isotactic polypropylene and atactic polystyrene were immersed in 3 saturated water solutions of alkali metal salts (LiCl, NaCl, and KCl) at 2 fixed temperatures (23°C and 90°C), and 3 DC electrical potentials (+4 kV, −4 kV, and ground potential) were applied. A quantification of alkali metals in the polymer sheets was conducted by inductively coupled plasma optic emission spectrometry. The obtained concentration values were from 7.38·10−9 mol/cm3 to 1.25·10−7 mol/cm3. The qualitative analysis of potassium distribution in the polymer matrix was conducted by time‐of‐flight secondary ion mass spectrometry cross‐sectional record. The relative dielectric constant (ε′) of samples was investigated in the frequency range from 20 Hz to 9 MHz at the constant temperature of 22°C. Stable values of ε′ in fully measured frequency range were observed for both pure and treated samples. Next, the results of the dielectric spectroscopy measurements were compared and established the kind of treatment that provided the highest value of ε′. The relationship between the concentrations of alkali metals and the values of relative dielectric constant was determined for the samples obtained by a treatment at 90°C and +4 kV.
Barriers and facilitators to sexual and reproductive health communication between pediatric oncology clinicians and adolescent and young adult patients: The clinician perspective
Authors: Frederick Natasha N. , Campbell Kevin , Kenney Lisa B. , Moss Kerry , Speckhart Ashley , Bober Sharon L. 
Published: April 2018

AbstractBackgroundSexual and reproductive health (SRH) is identified by adolescent and young adult (AYA) patients with cancer as an important but often neglected aspect of their comprehensive cancer care. The purpose of this study was to investigate the attitudes and perceptions of pediatric oncology clinicians towards discussing SRH with AYAs, and to understand perceived barriers to effective communication in current practice.ProcedurePediatric oncology clinicians (physicians, certified nurse practitioners, and physician assistants) participated in semi‐structured qualitative interviews investigating attitudes about SRH communication with AYAs and barriers to such conversations. Twenty‐two clinicians participated from seven institutions in the Northeastern United States. Interviews were audio‐recorded, transcribed, and coded using a thematic analysis approach.ResultsInterviews with pediatric oncology clinicians revealed the following five primary themes: the role for pediatric oncology clinicians to discuss SRH, the focus of current SRH conversations on fertility, the meaning of “sexual health” as safe sex and contraception only, clinician‐reported barriers to SRH conversations, and the need for education and support. Communication barriers included lack of knowledge/experience, lack of resources/referrals, low priority, parents/family, patient discomfort, clinician discomfort, time, and lack of rapport. Clinicians identified resource and support needs, including formal education and SRH education materials for patients and families.ConclusionsAlthough the study participants identified a role for pediatric oncology clinicians in SRH care for AYA patients with cancer, multiple barriers interfere with such discussions taking place on a regular basis. Future efforts must focus on resource development and provider education and training in SRH to optimize the care provided to this unique patient population.
Field‐evolved resistance of pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae), to transgenic Bacillus thuringiensis (Bt) cotton expressing crystal 1Ac (Cry1Ac) and Cry2Ab in India
Authors: Naik Vakudavath CB , Kumbhare Sujit , Kranthi Sandhya , Satija Usha , Kranthi Keshav R 
Published: April 2018

AbstractBACKGROUNDPink bollworm (PBW) adaptation to transgenic Bacillus thuringiensis (Bt) cotton expressing crystal 1Ac (Cry1Ac) (Bt‐I) and Cry1Ac + Cry2Ab (Bt‐II) was assessed in India during 2010–2017 in 38 districts of the 10 major cotton‐growing states.RESULTSPBW larval incidence on Bt cotton was nil in northern India, wherein the resistance ratios (RRs) to Cry1Ac were 26–262 and those to Cry2Ab were 1–108. In central and southern India, the annual average PBW larval recovery from Bt II cotton was high at 28.85–72.49% during 2014–2017. In central and southern India, the 50% lethal concentration (LC50) of Cry1Ac increased from a mean of 0.330 µg mL−1 (range 0.126–0.849 µg mL−1) in 2013 to a mean of 6.938 µg mL−1 (range 3.52 to 10.30 µg mL−1) in 2017 and the RR increased from a mean of 47.12 (range 18–121) in 2013 to a mean of 1387 (704–2060) in 2017, whereas the LC50 value for Cry2Ab increased from a mean of 0.014 µg mL−1 (range 0.004–0.094 µg mL−1) in 2013 to a mean of 12.51 µg mL−1 (range 3.92 to 28.10 µg mL−1) in 2017 and the RR increased from a mean of 5.4 (range 1–31) in 2013 to a mean of 4196 (1306–9366) in 2017.CONCLUSIONHigh PBW larval recovery on Bt‐II in conjunction with high LC50 values for Cry1Ac and Cry2Ab in major cotton‐growing districts of central and southern India provides evidence of field‐evolved resistance in PBW to Bt‐I and Bt‐II cotton. © 2018 Society of Chemical Industry
Therapeutic effect of Northern Labrador tea extracts for acute myeloid leukemia
Authors: McGill Colin M. , Tomco Patrick L. , Ondrasik Regina M. , Belknap Kaitlyn C. , Dwyer Gaelen K. , Quinlan Daniel J. , Kircher Thomas A. , Andam Cheryl P. , Brown Timothy J. , Claxton David F. , Barth Brian M. 
Published: April 2018

Acute myeloid leukemia (AML) is an aggressive hematological malignancy that is one of the more common pediatric malignancies in addition to occurring with high incidence in the aging population. Unfortunately, these patient groups are quite sensitive to toxicity from chemotherapy. Northern Labrador tea, or Rhododendron tomentosum Harmaja (a.k.a. Ledum palustre subsp. decumbens) or “tundra tea,” is a noteworthy medicinal plant used by indigenous peoples in Alaska, Canada, and Greenland to treat a diversity of ailments. However, laboratory investigations of Northern Labrador tea, and other Labrador tea family members, as botanical sources for anticancer compounds have been limited. Utilizing an AML cell line in both in vitro and in vivo studies, as well as in vitro studies using primary human AML patient samples, this study demonstrated for the first time that Northern Labrador tea extracts can exert anti‐AML activity and that this may be attributed to ursolic acid as a constituent component. Therefore, this medicinal herb holds the potential to serve as a source for further drug discovery efforts to isolate novel anti‐AML compounds.
A simplified silver phosphate extraction method for oxygen isotope analysis of bioapatite
Authors: Shabaga Brandi M. , Gough Hilary , Fayek Mostafa , Hoppa Robert D. 
Published: April 2018

RationaleAlthough phosphatic materials are chemically complex and are prone to exchange oxygen isotopes with their environments, the phosphate (PO43−) component of these materials is robust and retains its original oxygen isotopic composition. As a result, there are currently several methods for the isolation of phosphate oxygen through the precipitation of silver phosphate (Ag3PO4). However, some of these techniques produce Ag3PO4 of questionable purity, while nearly all are lengthy and/or require relatively large sample sizes.MethodsFive milligrams of bioapatite from modern cow teeth (enamel and cementum) were pre‐treated for removal of organic material prior to digestion in 2 M HF. The digested samples were titrated with silver ammine solution at 50°C to precipitate Ag3PO4. Oxygen isotopic data were collected using a Thermal Combustion Elemental Analyzer (TC/EA) paired with a Delta VPlus isotope ratio mass spectrometer via a ConFlo III universal interface.ResultsThe quality of Ag3PO4 is dependent on effective removal of organic material and the volume of silver ammine solution used during titration. A two‐step pre‐treatment of 2.5% NaOCl, followed by a 0.125 M NaOH solution, is the most effective treatment for the removal of organic material from both enamel and cementum. Optimal yields of Ag3PO4 were achieved using 1.8 mL of silver ammine solution. The reproducibility of the phosphate δ18O compositions ranges from 0.3 to 0.4‰ (1σ) for modern cow teeth.ConclusionsWe present a simplified method for phosphate extraction from organic‐rich phosphatic material. Our method gave reproducible δ18O values for enamel and cementum from cows' teeth.
Dynamic output‐feedback control for continuous‐time singular Markovian jump systems
Authors: Park Chan‐eun , Kwon Nam Kyu , Park PooGyeon 
Published: April 2018

SummaryThis paper considers a dynamic output‐feedback
control for continuous‐time singular Markovian jump systems, whereas the existing research studies in literature focused on state‐feedback or static output‐feedback
control. While they have only provided the sufficient conditions, this paper successfully obtains the necessary and sufficient condition for the existence of the dynamic output‐feedback
control. Furthermore, this condition is expressed with linear matrix inequalities by the so‐called replacement technique. Two numerical examples show the validity of the resulting control.
Cymene‐Osmium(II) Complexes with Amino‐Phosphane Ligands as Precatalysts for Nitrile Hydration Reactions
Authors: González‐Fernández Rebeca , Crochet Pascale , Cadierno Victorio 
Published: April 2018

AbstractThree different series of half‐sandwich Os(II) complexes, namely [OsCl2(η6‐p‐cymene){PPh2(NR2)}] [R=Me (5a), Et (5b)], [OsCl2(η6‐p‐cymene){PPh(NR2)2}] [R=Me (6a), Et (6b)] and [OsCl2(η6‐p‐cymene){P(NR2)3}] [R=Me (7a), Et (7b)], have been synthesized. These species proved to be catalytically active for the selective hydration of organonitriles, with compound [OsCl2(η6‐p‐cymene){PPh2(NMe2)}] (5a) being the most effective. In addition, the catalytic activity of5awas found to be superior to those shown by related Ru(II), Ru(IV), Rh(I) and Pt(II) species containing the amino‐phosphane PPh2(NMe2), i. e. compounds [RuCl2(η6‐p‐cymene){PPh2(NMe2)}] (10), [RuCl2(η3:η3‐C10H16){PPh2(NMe2)}] (12), [RhCl(COD){PPh2(NMe2)}] (13) andcis‐[PtCl2{PPh2(NMe2)}2] (15). Details on the synthesis and characterization of complexes10,12and15are also included, along with a discussion on the role played by the ligand PPh2(NMe2) during the catalytic reactions. In this sense, the amino‐phosphane does not act as H‐bond acceptor for the water molecule, generating instead in the aqueous reaction medium the cooperative phosphinous acid ligand PPh2(OH).
Thermal Engineering in Low‐Dimensional Quantum Devices: A Tutorial Review of Nonequilibrium Green's Function Methods
Authors: Chen Xiaobin , Liu Yizhou , Duan Wenhui 
Published: April 2018

AbstractThermal engineering of quantum devices has attracted much attention since the discovery of quantized thermal conductance of phonons. Although easily submerged in numerous excitations in macrosystems, quantum behaviors of phonons manifest in nanoscale low‐dimensional systems even at room temperature. Especially in nanotransport devices, phonons move quasiballistically when the transport length is smaller than their bulk mean free paths. It has been shown that the phonon nonequilibrium Green's function method (NEGF) is effective for the investigation of nanoscale quantum transport of phonons. Here, two aspects of thermal engineering of quantum devices are discussed using NEGF methods. One covers transport properties of pure phonons; the other concerns caloritronic effects, which manipulate other degrees of freedom, such as charge, spin, and valley, via the temperature gradient. For each part, the basic theoretical formalisms are outlined first, then a survey of related investigations on models or realistic materials is presented. Particular attention is given to phonon topologies and the generalized phonon NEGF method. Finally, conclusions are offered and the study is summarized with an outlook.
Neural network for software reliability analysis of dynamically weighted NHPP growth models with imperfect debugging
Authors: Rani Pooja , Mahapatra G.S. 
Published: April 2018

SummaryThis paper propose a learning algorithm of supervised back‐propagation neural networks for dynamic weighted combination of software reliability model. The proposed model is an assimilation of 3 well‐known non‐homogeneous poisson process (NHPP)–based software reliability growth models with imperfect debugging. The novel approach of proposed supervised back propagation–based neural network 2‐stage architecture has a great impact on the network by combining the imperfect debugging models based on the nature of fault introduction rate during testing and debugging. Function approximation metrics are used for comparing the proposed model with individual models. Three data sets are trained using supervised back‐propagation neural networks to compare the performance and validity evaluation of proposed and existing NHPP models and dynamic weighted combinational model. Reliability analysis among important NHPP models incorporating imperfect debugging is illustrated through numerical and graphical explanation of several metrics using supervised back‐propagation neural networks.
Phenological Diversity of Salmon Smolt Migration Timing within a Large Watershed
Authors: Carr‐Harris Charmaine N. , Moore Jonathan W. , Gottesfeld Allen S. , Gordon Jennifer A. , Shepert William M. , Henry James D. J. , Russell Harvey J. , Helin Wade N. B. , Doolan David J. , Beacham Terry D. 
Published: April 2018

AbstractAlthough there is growing concern that climate change might drive phenological mismatches between predators and prey, it is possible that within‐ and among‐species phenological variation provides resilience against such a mismatch. One key life history event that may be vulnerable to climate‐induced mismatch is the seaward migration of juvenile salmon relative to the spring bloom of their marine zooplankton prey. Here, we quantified phenological diversity of out‐migration timing among salmon populations within a large watershed and its implications for climate mismatches with marine zooplankton. Specifically, we sampled juvenile Sockeye Salmon Oncorhynchus nerka throughout the spring and early summer in the estuary of the Skeena River, a vast watershed with numerous locally adapted salmon populations that support commercial, recreational, and First Nations fisheries, and we used genetic stock identification to link the fish to their population of origin. We found that Sockeye Salmon were migrating through the estuary for more than 50 d, with peak emigration for different populations varying by over 5 weeks. The out‐migration timing of specific populations was related to geographic factors, including elevation of the rearing lake and the river distance between individual rearing lakes and the estuary, with different populations arriving 1.5 d later for every 100 m of elevation or 3 d later for every 100 km of river distance. Concurrent with sampling, we quantified the estuarine prey of juvenile Sockeye Salmon; zooplankton species composition and abundance varied throughout the smolt migration period, and the different salmon populations encountered different prey abundances upon ocean entry. Together, these results indicate underappreciated phenological diversity in this harvested metapopulation, which may contribute to response diversity and metapopulation‐level resilience to climate change.
Androgen Receptor CAG Repeat Length as a Risk Factor of Late-Onset Hypogonadism in a Korean Male Population
Authors: Kim Jong Wook , Bae Young Dae , Ahn Sun Tae , Kim Jin Wook , Kim Je Jong , Moon Du Geon 
Published: April 2018

Abstract

Background
Testosterone action is mediated through the androgen receptor (AR), whose sensitivity is influenced by the AR CAG repeat polymorphism. However, the relation between late-onset hypogonadism (LOH) and AR CAG repeat length is unclear and studies of Asian populations are limited.

Aim
To investigate the relation between AR CAG repeat length and LOH in Korean men.

Methods
263 Korean men (mean age = 63.43 ± 10.9 years) were enrolled from 2014 to 2015. LOH diagnosis was based on a serum testosterone level lower than 3.5 ng/mL and positive androgen deficiency according to the Aging Males’ Symptom Scale (AMS). Total testosterone levels and answers to the LOH-related questionnaire were analyzed.

Outcomes
The relation between AR CAG repeat length and LOH was determined.

Results
Mean CAG repeat length was 22.1 ± 4.6 and mean serum testosterone levels were 2.6 ± 0.7 and 6.0 ± 2.0 ng/mL in men with and without LOH, respectively. Men with LOH showed significantly longer AR CAG repeat lengths than men without LOH (26.1 vs 21.6, P &lt; .001). Longer CAG repeat lengths were correlated with higher AMS total scores (r = 0.454, P = .001) and AMS psychotic, somatic, and sexual sub-scores (r = 0.276, 0.246, and 0.571, P = .006, .007, .001, respectively) and significantly lower 5-item International Index of Erectile Function scores (r = −0.261, P = .001). Multivariate analysis showed that patient age and CAG repeat length were independently associated with LOH (odds ratio = 1.05 and 1.29, P = .041 and &lt;.001, respectively).

Clinical Implications
A longer CAG repeat length is associated with LOH symptoms and LOH.

Strengths and Limitations
Associations between CAG repeats and LOH were verified in Korean patients. Moreover, a longer CAG repeat length was shown to be an independent risk factor for LOH. Limitations included the small number of LOH patients studied and that other sex hormone-associated factors were not measured.

Conclusions
AR CAG repeat length was associated with LOH prevalence and clinical symptoms in this Korean male population. Thus, it is important to measure CAG repeat length for patients with LOH symptoms with normal testosterone levels.
Acetylcholinesterase inhibitors and risk of stroke and death in people with dementia
Authors: Tan Edwin C.K. , Johnell Kristina , Garcia‐Ptacek Sara , Haaksma Miriam L. , Fastbom Johan , Bell J. Simon , Eriksdotter Maria 
Published: April 2018

AbstractIntroductionThe aim of this study was to investigate the association between acetylcholinesterase inhibitor (AChEI) use and risk of ischemic stroke and death in people with dementia.MethodsA cohort study of 44,288 people with dementia registered in the Swedish Dementia Registry from 2007 to 2014. Propensity score‐matched competing risk regression models were used to compute hazard ratios and 95% confidence intervals for the association between time‐dependent AChEI use and risk of stroke and death.ResultsCompared with matched controls, AChEI users had a lower risk of stroke (hazard ratio: 0.85, 95% confidence interval: 0.75–0.95) and all‐cause death (hazard ratio: 0.76, 95% confidence interval: 0.72–0.80). After considering competing risk of death, high doses (≥1.33 defined daily doses) of AChEI remained significantly associated with reduced stroke risk.DiscussionThe use of AChEIs in people with dementia may be associated with reduced risk of ischemic stroke and death. These results call for a closer examination of the cardiovascular effects of AChEIs.
Randomized, controlled, proof‐of‐concept trial of MK‐7622 in Alzheimer's disease
Authors: Voss Tiffini , Li Jerry , Cummings Jeffrey , Farlow Martin , Assaid Christopher , Froman Samar , Leibensperger Heather , Snow‐Adami Linda , McMahon Kerry Budd , Egan Michael , Michelson David 
Published: April 2018

AbstractIntroductionWe evaluated the selective M1 muscarinic positive allosteric modulator, MK‐7622, as adjunctive cognitive enhancing therapy in individuals with Alzheimer's disease.MethodsA randomized, double‐blind, proof‐of‐concept trial was performed. Participants with mild‐to‐moderate Alzheimer's disease, being treated with an acetylcholinesterase inhibitor, were randomized 1:1 to 45 mg of MK‐7622 or placebo for 24 weeks. Endpoints included the mean change from baseline in Alzheimer's Disease Assessment Scale–Cognitive Subscale (ADAS‐Cog11) at 12 weeks and Alzheimer's Disease Cooperative Study–Activities of Daily Living Inventory at 24 weeks.ResultsTwo hundred forty participants were randomized. The trial was stopped for futility after meeting prospectively defined stopping criteria. MK‐7622 did not improve cognition at 12 weeks (group difference in ADAS‐Cog11: 0.18 [95% confidence interval: −1.0 to 1.3]) or function at 24 weeks (group difference in Alzheimer's Disease Cooperative Study–Activities of Daily Living Inventory: 0.06 [95% confidence interval: −2.4 to 2.5]). More participants taking MK‐7622 discontinued study medication because of adverse events than those taking placebo (16% vs 6%) and who experienced cholinergically related adverse events (21% vs 8%).DiscussionMK‐7622 (45 mg) does not improve cognition or function when used as adjunctive therapy in mild‐to‐moderate Alzheimer's disease.