bluuebunny/crossref_metadata_2025 huggingface dataset:
Feasibility of absolute quantification for 31P MRS at 7 T
Authors: Purvis Lucian A. B. , Valkovič Ladislav , Robson Matthew D. , Rodgers Christopher T.
Published: March 2019

Purpose

Phosphorus spectroscopy can differentiate among liver disease stages and types. To quantify absolute concentrations of phosphorus metabolites, sensitivity calibration and transmit field () correction are required. The trend toward ultrahigh fields (7 T) and the use of multichannel RF coils makes this ever more challenging. We investigated the constraints on reference phantoms, and implemented techniques for the absolute quantification of human liver phosphorus spectra acquired using a 10‐cm loop and a 16‐channel array at 7 T.

Methods

The effect of phantom conductivity was assessed at 25.8 MHz (1.5 T), 49.9 MHz (3 T), and 120.3 MHz (7 T) by electromagnetic modeling. Radiofrequency field maps () were measured in phosphate phantoms (18 mM and 40 mM) at 7 T. These maps were used to assess the correction of 4 phantom 3D‐CSI data sets using 3 techniques: phantom replacement, explicit normalization, and simplified normalization. In vivo liver spectra acquired with a 10‐cm loop were corrected with all 3 methods. Simplified normalization was applied to in vivo 16‐channel array data sets.

Results

Simulations show that quantification errors of less than 3% are achievable using a uniform electrolyte phantom with a conductivity of 0.23‐0.86 S.m−1 at 1.5 T, 0.39‐0.58 S.m−1 at 3 T, and 0.34‐0.42 S.m−1 (16‐19 mM KH2PO4(aq)) at 7 T. The mean γ‐ATP concentration quantified in vivo at 7 T was 1.39 ± 0.30 mmol.L−1 to 1.71 ± 0.35 mmol.L−1 wet tissue for the 10‐cm loop and 1.88 ± 0.25 mmol.L−1 wet tissue for the array.

Conclusion

It is essential to select a calibration phantom with appropriate conductivity for quantitative phosphorus spectroscopy at 7 T. Using an 18‐mM phosphate phantom and simplified normalization, human liver phosphate metabolite concentrations were successfully quantified at 7 T.
Hydro‐micromechanical modeling of wave propagation in saturated granular crystals
Authors: Cheng Hongyang , Luding Stefan , Rivas Nicolás , Harting Jens , Magnanimo Vanessa
Published: March 2019

Biot theory predicts wave velocities in a saturated granular medium using the pore geometry, viscosity, densities, and elastic moduli of the solid skeleton and pore fluid, neglecting the interaction between constituent particles and local flow, which becomes essential as the wavelength decreases. Here, a hydro‐micromechanical model, for direct numerical simulations of wave propagation in saturated granular media, is implemented by two‐way coupling the lattice Boltzmann method (LBM) and the discrete element method (DEM), which resolve the pore‐scale hydrodynamics and intergranular behavior, respectively. The coupling scheme is benchmarked with the terminal velocity of a single sphere settling in a fluid. In order to mimic a small amplitude pressure wave entering a saturated granular medium, an oscillating pressure boundary on the fluid is implemented and benchmarked with the one‐dimensional wave equation. The effects of input waveforms and frequencies on the dispersion relations in 3D saturated poroelastic media are investigated with granular face‐centered‐cubic crystals. Finally, the pressure and shear wave velocities predicted by the numerical model at various effective confining pressures are found to be in excellent agreement with Biot analytical solutions, including his prediction for slow compressional waves.
Adaptive radial basis function–generated finite differences method for contact problems
Authors: Slak Jure , Kosec Gregor
Published: March 2019

This paper proposes an original adaptive refinement framework using radial basis function–generated finite differences method. Node distributions are generated with a Poisson disc sampling–based algorithm from a given continuous density function, which is altered during the refinement process based on the error indicator. All elements of the proposed adaptive strategy rely only on meshless concepts, which leads to great flexibility and generality of the solution procedure. The proposed framework is tested on four gradually more complex contact problems. First, a disc under pressure is considered and the computed stress field is compared to the closed‐form solution of the problem to assess the behaviour of the algorithm and the influence of free parameters. Second, a Hertzian contact problem is studied to analyse the proposed algorithm with an ad hoc error indicator and to test both refinement and derefinement. A contact problem, typical for fretting fatigue, with no known closed‐form solution is considered and solved next. It is demonstrated that the proposed methodology produces results comparable with finite element method without the need for manual refinement or any human intervention. In the last case, generality of the proposed approach is demonstrated by solving a three‐dimensional Boussinesq's problem.
Health‐related quality of life and related factors among a sample of older people with cognitive impairment
Authors: Christiansen Line , Sanmartin Berglund Johan , Lindberg Catharina , Anderberg Peter , Skär Lisa
Published: March 2019

Aim

This study aimed to identify factors affecting health‐related quality of life (HRQoL) of older adults with cognitive impairment and to describe the association of these factors with different components of HRQoL.

Design

A cross‐sectional, descriptive research design was used.

Methods

Data were collected from 247 individuals aged 60 years and older from a Swedish longitudinal cohort study. The Short‐Form Health Survey‐12 (SF‐12) and EuroQol (EQ‐5D) were used to assess HRQoL. The data were analysed using descriptive and comparative statistics.

Results

The present study identified several factors that influenced HRQoL of older adults with cognitive impairment. The results of a multiple logistic regression analysis revealed that the following factors were associated with physical and mental HRQoL: dependency in activities of daily living (ADL), receiving informal care and feelings of loneliness and pain.
The Macroeconomic Effects of 2017 Through 2025 Federal Fuel Economy and Greenhouse Gas Emissions Standards
Authors: Carley Sanya , Zirogiannis Nikolaos , Duncan Denvil , Siddiki Saba , Graham John D.
Published: March 2019

In the absence of a national carbon price, the federal Corporate Average Fuel Economy standards and the related greenhouse gas emissions (GHG) standards are the primary mechanisms through which the U.S. reduces transportation GHG emissions. In 2012, these standards were set to rise for light‐duty vehicles between 2017 and 2025, eventually achieving a target of 54.5 miles per gallon in 2025. Since 2012, conditions have changed: forecasts of future gasoline prices have dropped dramatically, consumers have demanded larger vehicles, and the cost of compliance appears to be larger than previously thought. In this article, we analyze the possible macroeconomic effects of the standards with both 2012 inputs and updated inputs to reflect these new market developments. The results reveal that the short‐term effects of the federal standards will be negative, but the long‐term effects will be positive, using both 2012 and updated inputs. The transition from annual negative employment impacts to positive impacts occurs between 2023 and 2026, depending on which set of assumptions are used. Possible revisions to the standards that freeze them at 2020 levels or decrease their stringency reduce short‐term negative impacts but also reduce long‐term positive impacts. We conclude with a discussion of policy implications as they relate to the current energy and climate policy conditions.
Use of ion mobility mass spectrometry to enhance cumulative analytical specificity and separation to profile 6‐C/8‐C‐glycosylflavone critical isomer pairs and known–unknowns in medicinal plants
Authors: McCullagh Michael , Pereira Cintia Alessandra Matiucci , Yariwake Janete Harumi
Published: March 2019

Introduction

Plant medicine/herbal extracts are typically complex, encompassing a wide range of flavonoid diversity and biological benefits. Combined with a lack of standards; species authentication profiling is a challenge. A non‐targeted screening strategy using two‐dimensional (2D) separation and specificity of ultra‐high‐performance liquid chromatography ion mobility collision‐induced dissociation mass spectrometry (UHPLC‐IM‐CID‐MS) has been investigated, to identify the 6‐C and 8‐C‐glycosylflavone isomer orientin/isoorientin and vitexin/isovitexin pairs in Passiflora species. Utilising available standards and “known–unknowns” a reference CCS (collision cross‐section) speciation finger print for Passiflora extracts could be generated to illustrate species profiling.

Material and Methods

SPE was performed to extract flavonoids of interest from powdered and ground Passiflora leaf. Chromatographic separation was achieved via UHPLC and analysis performed using positive/negative ion electrospray coupled with linear T‐wave IM‐MS (calibrated to perform accurate mass and CCS measurements).

Results

Comparative phytochemical screening of Passiflora alata, P. edulis, P. incarnata and P. caerulea leaf extracts has generated CCS, CID IM product ion spectra, 2D separation with UHPLC‐IM‐MS, enabling the unequivocal identification of flavone C‐glycosides in complex extracts. A phytochemical reference CCS library was generated comprised of “knowns” and “known–unknowns”. Isomers have been differentiated using a CCS metric enabling novel CCS specific isomeric quantitation of co‐eluting isomers.

Conclusions

The screening approach illustrated has the potential to play an important role in the profiling of medicinal plants to determine phytochemical make‐up and improve consumer safety through generation of highly specific speciation profiles.
Evaluation of Clinical and Safety Outcomes Following Uncontrolled Tacrolimus Conversion in Adult Transplant Recipients
Authors: Lichvar Alicia , Tremblay Simon , Naik Devanshi , Lipscomb Jessi , King Eileen , Vinks Alexander A. , Christians Uwe , Alloway Rita R.
Published: March 2019

Purpose

To compare clinical and safety outcomes of transplant recipients converted between different tacrolimus formulations to those patients who remained on a single formulation in an outpatient environment.

Methodology

This was a single‐center, retrospective cohort study at a large tertiary care medical center with an associated institutional outpatient pharmacy system. Adult transplant recipients with institutional pharmacy refill from August 1, 2009, to May 31, 2016, were assessed. Patients were allocated into four separate groups: Group (A) innovator tacrolimus (no conversion), Group (B) generic tacrolimus (no conversion), Group (C) single conversion (from innovator to single generic or from generic to innovator tacrolimus), and Group (D) multiple conversions. Index date was either the date of first tacrolimus product conversion (Groups C and D) or a pre‐specified post‐transplant time (Groups A and B).

Results

Overall, 100 patients were included in the analysis, 63% were male, 62% were Caucasian, and 59% were renal transplant recipients. When compared between groups, linear trends in dose‐normalized tacrolimus levels were similar in the pre‐index date period (p=0.52) and in the post‐index date period (p=0.08). When groups were compared individually, linear trends in dose‐normalized tacrolimus levels were significantly different pre‐ versus post‐index date for Group B (p=0.008). There were no differences in the linear trends of dose‐normalized tacrolimus levels across the other groups (p>0.05 for all). After the index date, 43% of patients across all groups required tacrolimus dose modification with no differences by group (p=0.32). Allograft function and hospitalizations were similar across all groups.

Conclusions

Conversion between tacrolimus generic formulations has been suggested to be unsafe. This study demonstrates that switching tacrolimus products in post‐transplant recipients does not alter dose‐normalized tacrolimus trough concentrations, renal or hepatic function, pathology, or hospitalizations.
Proteomes of Leaf‐Growing Zones in Rice Genotypes with Contrasting Drought Tolerance
Authors: Wu Yunqi , Mirzaei Mehdi , Pascovici Dana , Haynes Paul A. , Atwell Brian J.
Published: March 2019

Plants require a distinctive cohort of enzymes to coordinate cell division and expansion. Proteomic analysis now enables interrogation of immature leaf bases where these processes occur. Hence, proteins in tissues sampled from leaves of a drought‐tolerant rice (IAC1131) are investigated to provide insights into the effect of soil drying on gene expression relative to the drought‐sensitive genotype Nipponbare. Shoot growth zones are dissected to estimate the proportion of dividing cells and extract protein for subsequent tandem mass tags quantitative proteomic analysis. Gene ontology annotations of differentially expressed proteins provide insights into responses of Nipponbare and IAC1131 to drought. Soil drying does not affect the percentage of mitotic cells in IAC1131. More than 800 proteins across most functional categories increase in drought (and decrease on rewatering) in IAC1131, including proteins involved in “organizing the meristem” and “new cell formation”. On the other hand, the percentage of dividing cells in Nipponbare is severely impaired during drought and fewer than 200 proteins respond in abundance when growing zones undergo a drying cycle. Remarkably, the proteomes of the growing zones of each genotype respond in a highly distinctive manner, reflecting their contrasting drought tolerance even at the earliest stages of leaf development.
Discovery of a Novel Connecting Link between Renin–Angiotensin System and Cancer in Barrett's Esophagus by Proteomic Screening
Authors: Rao Rashmi , Husain Amjad , Bharti Alok C. , Kashyap Manoj K.
Published: March 2019

The renin–angiotensin system (RAS) plays a central role in the regulation of homeostasis and blood pressure. This involves an important enzyme called angiotensin‐converting enzyme that leads to the conversion of angiotensin I into angiotensin II. RAS has been reported to show association with inflammation, and in sporadic studies, with cancer. In particular, angiotensin II has been reported to be prevalent in the hypoxic microenvironment and associated with cancer signaling pathways. In a recent study, Bratlie et al. (Proteomics Clin. Appl. 2019, 4, 1800102) is shown to exploit 2D gel electrophoresis, and mass spectrometry (MS) to identify differentially expressed proteins by comparing low‐grade dysplasia in Barrett's Esophagus (BE) following administration of agents that interfere with RAS, that is, enalapril and candesartan, and identified specific modulation of HSP60, PDIA3, and PPA1. Though 2D gel coupled with MS is a commonly‐used tool for studying proteomes, it still has limitations in terms of a comprehensive analysis due to lack of absolute quantitation in a high‐throughput manner. Despite technical limitations and the small size of the study, preliminary data emerging from the investigation show interference caused by clinically approved RAS inhibitors resulting in alteration of molecular markers associated with tumorigenicity. The authors propose potential factors that may influence the progression of the disease. However, these are conspicuous changes in high‐abundance proteins only. Therefore, there is a need to carry out detailed experimental studies either using an in vitro labeling technique (isobaric labeling for relative and absolute quantitation) for tissues or an in vivo labeling technique (stable isotope labeling in animal cell culture) coupled with LC‐MS/MS to identify differentially‐regulated proteins to delineate the role of RAS in BE.
In Memoriam Leonid V. Keldysh
Authors: Bonitz Michael , Jauho Antti‐Pekka , Sadovskii Michael , Tikhodeev Sergei
Published: March 2019

Leonid V. Keldysh – one of the most influential theoretical physicists of the 20th century – passed away in November 2016. L. V. Keldysh is best known for the diagrammatic formulation of real‐time (nonequilibrium) Green functions theory and for the theory of strong field ionization of atoms. Both theories profoundly changed large areas of theoretical physics and stimulated important experiments. Both these discoveries emerged almost simultaneously – like Einstein, also L. V. Keldysh had his annus mirabilis – the year 1964. But the list of his theoretical developments is much broader and is briefly reviewed here.
Exploring point defects in hexagonal boron‐nitrogen monolayers
Authors: Korona Tatiana , Chojecki Michał
Published: March 2019

A comprehensive theoretical study of selected point defects for a monolayer of hexagonal boron nitride (h‐BN) is presented. Two‐dimensional structures were simulated through largeh‐BN molecular clusters and used to examine various defects, like: atom vacancies, atom substitutions, or distortions of the hexagonal lattice. Since carbon contaminations are very common in theh‐BN technology, a particular attention has been paid to carbon impurities. The calculations of IR spectra for the doped molecular clusters reveal the presence of additional frequencies, which in many cases correspond to defect‐bound modes. In particular, when two carbon atoms are close to each other, a localized stretching CC mode of a high intensity has been found, with a frequency value of about 100‐200 cm–1higher than for collective BN stretch frequencies. Absorption UV‐Vis spectra obtained from time‐dependent density functional theory show that the inclusion of impurities results in an emergence of several low‐energy electronic excitations, from which some are localized on a defect, while other are delocalized. Energies of these excitations are strongly dependent on the defect type, and they range from about 0.7 to 6.1 eV for the lowest excitations. Based on UV‐Vis spectra we propose several candidates which could be responsible for the experimental 4 eV color band. These defects are built from two or four adjacent carbon atoms and have the lowest excitation ranging from 3.9 to 4.8 eV, which is strongly localized on the defect.
In silico, in vitro and in vivo metabolite identification of brexpiprazole using ultra‐high‐performance liquid chromatography/quadrupole time‐of‐flight mass spectrometry
Authors: Thakkar Disha , Kate Abhijeet S.
Published: March 2019

Rationale

Brexpiprazole is a novel serotonin–dopamine activity modulator approved by the USFDA in July 2015 for the treatment of schizophrenia and as an adjunctive therapy with other antidepressants for major depressive disorder in adults. However, limited numbers of metabolites are reported in the literature for brexpiprazole. Our prime intent behind this study is to revisit metabolite profiling of brexpiprazole and to identify and characterize all possible in vitro and in vivo metabolites.

Methods

Firstly, the site of metabolism for brexpiprazole was predicted by a Xenosite web predictor model. Secondly, in vitro metabolite profiling was performed by incubating the drug individually with rat liver microsomes, human liver microsomes and rat S9 fraction at 37°C for 1 h in incubator shaker. Finally, for in vivo metabolite identification, a 50 mg kg−1 dose of brexpiprazole was administered to male Sprague–Dawley rats and the presence of various metabolites was confirmed in rat plasma, urine and feces.

Results

The predicted atomic site of metabolism was obtained as a color gradient by the Xenosite web predictor tool and, from this study, probable metabolites were listed. In total, 14 phase I and 2 phase II metabolites were identified and characterized in the in vitro and in vivo matrices using ultra‐high‐performance liquid chromatography/quadrupole time‐of‐flight tandem mass spectrometry (UHPLC/QTOF‐MS/MS). The majority of metabolites were found in the sample incubated with human liver microsomes and in rat urine, while in the other matrices only a few metabolites were detected.

Conclusions

All the 16 metabolites were identified and characterized using UHPLC/QTOF‐MS/MS. The study revealed that brexpiprazole is metabolized via hydroxylation, glucuronidation, S‐oxidation, N‐oxidation, dioxidation, oxidative deamination, N‐dealkylation, etc.
Negative pressure wound therapy with instillation without open‐window thoracostomy for empyema
Authors: Okamoto Kayo , Matsumoto Kumiko , Iga Norichika , Komatsu Seiji
Published: March 2019

Treatment of empyema is very challenging. The use of negative pressure wound therapy (NPWT), and NPWT with instillation and dwell time (NPWTi‐d) for wound closure have attracted attention. However, they are both limited to use after open‐window thoracostomy (OWT) performed to control infection. In some patients with poor general conditions, who cannot undergo surgery, no treatment for empyema is available. Therefore, we devised a new treatment for such patients with NPWTi‐d without OWT (non‐OWT NPWTi‐d). Here we present the cases of two patients with refractory empyema after intrathoracic irrigation and drainage, who underwent non‐OWT NPWTi‐d using the fistula of the thoracic drain. Both the patients recovered. The first patient was treated for 31 days. As the empyema persisted, he underwent a repeat intrathoracic drainage after which the wound healed. The second patient was treated for 20 days. Non‐OWT NPWTi‐d may be a new option to treat empyema.
Systematic Investigation on the Adsorption Performance and Mechanism of MnO2/TA Nanoflowers for Cu(II) Removal from Aqueous Solution
Authors: Gao Hongtao , Xiu Master. Q. , Wang Master. Y. , Zhan Bachelor. Y. , Deng Xiaoyan , Xu Yongji , Dai Dongmei , Liu Xien , Si Chongdian , Liu Guangun
Published: March 2019

In this work, a nanoflower‐type manganese dioxide composite with tannic acid (MnO2/TA) was prepared using a facile hydrothermal method. The maximum adsorption capacity of nanoflower MnO2/TA for Cu(II) removal from aqueous solution was 194.3 mg⋅g−1, and this illustrated the excellent adsorptive activity of nanoflower MnO2/TA. Adsorption kinetics and isotherm investigations showed that pseudo second order kinetics and the Langmuir isotherm model fit the experimental data well. The surface complex formation model (SCFM) was used to study the adsorptive process and mechanism of Cu(II) adsorption on the surface of MnO2/TA. Further investigation indicated that the adsorption energies for various forms of Cu(II) were negative which indicated that Cu(II) adsorption on MnO2/TA was a spontaneous process. Electrostatic interactions and chemical complexation were involved in Cu(II) removal by MnO2/TA from aqueous solution. The decline of adsorption capacity was about 10% for MnO2/TA after being reused five times, and this showed that the adsorbent might be reused in Cu(II) removal. The MnO2/TA nanocomposite has been proven to be a low‐cost and efficient adsorbent that could be a potential material for use in environmental treatment. Understanding the adsorption mechanism might provide a technical basis for the processual design of heavy metal adsorbents.
An Efficient and Eco‐Friendly One‐Pot Synthesis of Pyrazolopyridines Mediated by Choline Chloride/Urea Eutectic Mixture
Authors: Vanegas Sebastián , Rodríguez Daniel , Ochoa‐Puentes Cristian
Published: March 2019

In this contribution several choline chloride‐based deep eutectic solvents were evaluated as novel reaction media for the multicomponent one‐pot synthesis of pyrazolopyridine derivatives. It was found that the reaction between hydrazines, ethyl acetoacetate, ammonium acetate and aldehydes or ketones is efficiently catalyzed by the eutectic mixture choline chloride/urea yielding a wide variety of tetrahydrodipyrazolopyridine derivatives in good to excellent yields. In addition, the low melting mixture was reused in four cycles without observing a detrimental catalytic activity.
A formal framework for measuring technical lag in component repositories — and its application to npm
Authors: Zerouali Ahmed , Mens Tom , Gonzalez‐Barahona Jesus , Decan Alexandre , Constantinou Eleni , Robles Gregorio
Published: March 2019

Reusable Open Source Software (OSS) components for major programming languages are available in package repositories. Developers rely on package management tools to automate deployments, specifying which package releases satisfy the needs of their applications. However, these specifications may lead to deploying package releases that are outdated, or otherwise undesirable, because they do not include bug fixes, security fixes, or new functionality. In contrast, automatically updating to a more recent release may introduce incompatibility issues. To capture this delicate balance, we formalise a generic model of technical lag, a concept that quantifies to which extent a deployed collection of components is outdated, with respect to the ideal deployment. We operationalise this model for the npm package manager. We empirically analyze the history of package update practices and technical lag for more than 500K packages with about 4M package releases over a seven‐year period. We consider both development and runtime dependencies, and study both direct and transitive dependencies. We also analyze the technical lag of external GitHub applications depending on npm packages. We report our findings, suggesting the need for more awareness of, and integrated tool support for, controlling technical lag in software libraries.
Enhanced Power Conversion Efficiency in Solution‐Processed Rigid CuIn(S,Se)2 and Flexible Cu(In,Ga)Se2 Solar Cells Utilizing Plasmonic Au‐SiO2 Core‐Shell Nanoparticles
Authors: Chen Chia‐Wei , Chen Yi‐Ju , Thomas Stuart R. , Yen Yu‐Ting , Cheng Lung‐Teng , Wang Yi‐Chung , Su Teng‐Yu , Lin Hao , Hsu Cheng‐Hung , Ho Johnny C. , Hsieh Tung‐Po , Chueh Yu‐Lun
Published: March 2019

Plasmonic resonance effect triggered by gold nanoparticles (NPs) is utilized to enhance light harvesting in different types of thin‐film solar cells. However, there is no report using the plasmonic resonance effect triggered by metal NPs in chalcopyrite absorber‐based devices because of the high reactivity between the metal NPs and indium/copper/gallium during the required high‐temperature selenization process. In this work, Au NPs encapsulated by a thin protective silicon oxide shell in the chalcopyrite absorber‐based solar cells deposited by scalable solution deposition techniques under the 600 °C selenization process are demonstrated. The increased scattering and surface plasmonic resonance induced field generated by the nanoparticles can lead to significant enhancement in light absorption and charge carrier generation across a broad spectral range. Enhanced power conversion efficiency in solution‐processed rigid CuIn(S,Se)2 from 1.95 to 2.26% and flexible Cu(In,Ga)Se2 solar cells from 9.28% to 10.88% is achieved after the addition of plasmonic Au‐SiO2 core‐shell NPs in the absorber layer. This work demonstrates a facile method for chalcopyrite solar cell enhancement, which is compatible with low‐cost and high‐throughput manufacturing process.
Green marketing mix: A case study of Brazilian retail enterprises
Authors: Madeira Adriana Beatriz
Published: March 2019

The challenges posed by the limited availability of resources means that retail operations and methods must be revised and redesigned. Against the current backdrop of changes, companies are seeking to innovate the way in which they market their wares. Within this context, this article discusses the “green marketing mix” from the perspective of Brazilian retail enterprises. In addition, the study described in this article sought to identify and highlight the elements that should be considered when defining strategically each variable within the green retail marketing mix. As part of this work, a case study was carried out on two Brazilian retail companies. The case analysis revealed that despite defining themselves as “green,” when their retail marketing mix was analyzed, the companies presented differing degrees of sustainability. Furthermore, expanding the theoretical framework for the green retail marketing mix is a crucial issue in the services sector, and it has significant, practical repercussions.
Factor analysis: Latent variable, matrix decomposition, and constrained uniqueness formulations
Authors: Adachi Kohei
Published: March 2019

Factor analysis (FA) is a time‐honored multivariate analysis procedure for exploring the factors that underlie observed multiple variables to explain their variations. According to how the factors are treated, the formulations of FA can be classified into three approaches. One of them can be called a latent variable (LV) formulation, while the remaining two can be named matrix decomposition (MD) ones. The factors are regarded as random latent variables in the LV formulation, but treated as fixed parameter matrices in the MD ones. Here, the latter MD formulations are subdivided into the one simply called MD and the constrained uniqueness (CU) formulation with a special constraint. As compared to the LV formulation which is classic, MD and CU ones are recently established. Thus, it is useful to review the formulations now.

This article is categorized under:

Statistical and Graphical Methods of Data Analysis > Multivariate Analysis
Predictors of HPV Knowledge and HPV Vaccine Awareness Among Women in Panama City, Panama
Authors: Gantz Lisa , Calvo Arlene , Hess‐Holtz Morgan , Gonzales Fiorella , Alguero Lourdes , Murphy Sheila , Moran Meghan , Frank Lauren B. , Chatterjee Joyee S. , Amezola de Herrera Paula , Baezconde‐Garbanati Lourdes
Published: March 2019

In 2008, Panama became the first country in Latin America to offer the Human Papilloma Virus (HPV) vaccine at no cost to 10‐year‐old girls as part of its National Immunization Program. Vaccine completion rates remain suboptimal, and knowledge is limited regarding public perceptions of the HPV vaccine in Panama. A cross‐sectional survey of 333 Panamanian women aged 18–65 was conducted in Panama City, Panama. Although 93 percent of respondents had heard of HPV, only 59.8 percent had heard of the HPV vaccine. Acceptability of HPV vaccination of daughters was high (95 percent). In multivariate analyses, HPV vaccine awareness was associated with age and education, but not with income, Internet use as preferred source of health information, indigenous race, or marital status. Additionally, after controlling for age, education, income, race, and Internet use, women who completed a pap test in the past 36 months were 3.12 times more likely to have heard of the HPV vaccine when compared to those who had not (95%CI 1.04–9.34). Future efforts to educate Panamanian women about the HPV vaccine should include special attention to vulnerable populations, including those of younger age and limited education.
Access to Essential Medications and Equipment for Obstetric and Neonatal Primary Care in Bombali District, Sierra Leone
Authors: Koroma Manso Mohamed , Kamara Mohamed Amadu , Keita Namoudou , Lokossou Virgil K. , Sundufu Abu James , Jacobsen Kathryn H.
Published: March 2019

The increased demand for basic emergency obstetric and neonatal care (BEmONC) services in Sierra Leone since the launch of the nationwide free maternity care initiative in 2010 has strained the capacity of the system to provide high‐quality care. In 2014, members of our research team visited all 97 functioning primary health‐care facilities in Bombali district in the Northern Province of Sierra Leone to evaluate gaps in access to BEmONC. Although most facilities had the equipment necessary for maternal and neonatal care, these were often not in satisfactory condition. Most of the facilities did not stock all of the essential medicines for BEmONC, and less than 10 percent of the facilities had sufficient stocks of unexpired and properly stored medications. Stronger supply chains will be necessary to improve health system performance in Sierra Leone, reduce maternal mortality, increase neonatal survival, and achieve targets associated with the Sustainable Development Goals (SDGs).
Captive ring‐tailed lemur breeding in semi‐free ranging conditions and genetic parentage analysis
Authors: Breton Grégory , Thibault Sophie , Werts Mathieu , Baudry Emmanuelle
Published: March 2019

The ring‐tailed lemur (Lemur catta), one of the most iconic and widely recognized primates in the world, is threatened in its native range and classified as endangered by the International Union for Conservation of Nature. The global conservation strategy for the species includes ex situ conservation efforts led by zoological institutions in the framework of regional captive breeding programs. To maximize the conservation of genetic diversity and optimize breeding programs, an accurate pedigree must be established in captive populations. Our study documents the formation and subsequent monitoring of a large ring‐tailed lemur group in a French zoological institution. Based on staff's behavioral observations and DNA analyses using 11 microsatellite markers, we were able to document the survival and reproduction rates of the lemurs in this situation and reconstruct the pedigree of infants born in the institution. In total, 22 of the 28 imported animals as well as 4 locally born individuals gave birth to 58 infants of which 28 survived. The consistent genotypes obtained from the 53 sampled animals allowed us to identify 25 of the sires and 27 of the dams for the 28 surviving infants. A total of 12 different females and 14 different males produced the 28 surviving infants, suggesting that no individual dominates reproduction. This pioneering study has practical applications for the captive management of the species, which can be raised to the individual level instead of the group level.
A critical review of methods used to determine phosphorus and digestible amino acid matrices when using phytase in poultry and pig diets
Authors: Dersjant-Li Yueming , Hruby Milan , Evans Ceinwen , Greiner Ralf
Published: March 2019

Phytase is applied in animal feed based on its standard activity measured at pH 5.5, however the relative activity at pH 3 (e.g. stomach pH, the main site for the breakdown of phytate) varies among the commercial phytases, ranging from 56% (an E coli phytase) to 235% (Buttiauxella phytase). These diverse sources of phytases have varying capability for degrading phytate and, correspondingly, different P, digestible amino acid and metabolisable energy matrix values. In addition, the matrix values recommended by different phytase suppliers are not comparable, as different methodologies have been used to determine them. Phosphorus (P) and other matrix values can be determined by direct measurement of digestible P (dP) improvements by the addition of phytase above a negative control in large numbers of in vivo studies using increasing phytase doses. Alternatively, matrix values can be assessed by indirect measurement, using inorganic P (usually mono- or dicalcium sources) as a reference, typically based on tibia or metacarpal ash as a response parameter to estimate available P equivalence, either at a single or different phytase doses. When using the indirect measurement, the available P equivalence with increasing phytase doses may be calculated based on a log linear model. Although both methods are acceptable methodologies, direct measurement may under-estimate and indirect measurement may over-estimate matrix values, and a large number of in vivo studies give the best estimates of matrix values. Phytase efficacy can be influenced by phytase source, dose level, dietary composition (Ca level and Ca: P ratio). Phytase end users are encouraged to be aware of the methods used by suppliers to determine matrix values, before applying them in their feed formulations.
Load and loss for high-speed lubrication flows of pressurized gases between non-concentric cylinders
Authors: Chien S. Y. , Cramer M. S.
Published: March 2019

We examine the high-speed flow of pressurized gases between non-concentric cylinders where the inner cylinder rotates at constant speed while the outer cylinder is stationary. The flow is taken to be steady, two-dimensional, compressible, laminar, single phase and governed by a Reynolds lubrication equation. Approximations for the lubricating force and friction loss are derived using a perturbation expansion for large speed numbers. The present theory is valid for general Navier–Stokes fluids at nearly all states corresponding to ideal, dense and supercritical gases. Results of interest include the observation that pressurization gives rise to large increases in the lubricating force and decreases in the fluid friction. The lubrication force is found to scale with the bulk modulus. Within the context of the Reynolds equation an exact relation between total heat transfer and power loss is developed.
ESTIMATION FOR DYNAMIC PANEL DATA WITH INDIVIDUAL EFFECTS
Authors: Robinson Peter M. , Velasco Carlos
Published: March 2019

The article discusses statistical inference in parametric models for panel data. The models feature dynamics of a general nature, individual effects, and possible explanatory variables. The focus is on large-cross-section inference on Gaussian pseudo maximum likelihood estimates with temporal dimension kept fixed, partially complementing and extending recent work of the authors. We focus on a particular kind of initial condition but go on to discuss implications of alternative initial conditions. Some possible further developments are briefly reviewed.
Entiers friables dans des progressions arithmétiques de grand module
Authors: DE LA BRETÈCHE R. , FIORILLI D.
Published: March 2019

We study the average error term in the usual approximation to the number of y-friable integers congruent to a modulo q, where a ≠ 0 is a fixed integer. We show that in the range exp{(log log x)5/3+ɛ} ⩽ y ⩽ x and on average over q ⩽ x/M with M → ∞ of moderate size, this average error term is asymptotic to −|a| Ψ(x/|a|, y)/2x. Previous results of this sort were obtained by the second author for reasonably dense sequences, however the sequence of y-friable integers studied in the current paper is thin, and required the use of different techniques, which are specific to friable integers.
Half‐Graben Rupture Geometry of the 30 October 2016 MW6.6 Mt. Vettore‐Mt. Bove Earthquake, Central Italy
Authors: Cheloni D. , Falcucci E. , Gori S.
Published: March 2019

Existing models for the rupture geometry and slip distribution associated with the 30 October MW6.6 Mt. Vettore‐Mt. Bove earthquake in central Italy show significant dissimilarities. Indeed, due to the quite complicated observed deformation pattern, the activation of a complex multifault structure during a single seismic event was invoked. In this study, we explore different rupture scenarios and we develop a robust model of the rupture process of the 30 October earthquake, designed from new field observations, aftershock distribution, and static coseismic offsets including new near‐field survey‐mode global position system measurements, regional Global Positioning System observations, Interferometric Synthetic Aperture Radar interferograms, and static displacements derived from strong‐motion stations. Our preferred best fit model involves the simultaneous rupture of the master Mt. Vettore‐Mt. Bove normal fault and of at least two secondary antithetic faults (as they significantly contributed to the total deformation field), which overall describe a “simple conceptual” half‐graben normal fault system and whose arrangement fits the geological, seismological, and coseismic evidence of surface faulting. Notably, our model fits the geometry of seismogenic structures defined prior to the 2016–2017 seismic sequence by field Quaternary geological observations. In addition, no significant coseismic slip on faults alternative to the master and antithetic faults is necessary to explain the observed surface displacements during the 30 October Mt. Vettore‐Mt. Bove earthquake.
The Equatorial Undercurrent and Its Origin in the Region Between Mindanao and New Guinea
Authors: Wang Qingye , Wang Fujun , Feng Junqiao , Hu Shijian , Zhang Linlin , Jia Fan , Hu Dunxin
Published: March 2019

Herein, the spatial characteristics of the Equatorial Undercurrent (EUC) in the region between Mindanao and New Guinea and the origins of the EUC and the North Equatorial Countercurrent (NECC) were investigated using a combination of high‐resolution Argo hydrographic data and numerical modeling. The Mindanao Current (MC) results in the formation of a strong EUC‐depth eastward current that splits into two branches near the Halmahera Eddy west of 132°E, with one branch directly flowing eastward without experiencing the Halmahera Eddy rotation effect, and the other branch flowing southwestward and then turning northeastward. The EUC and NECC were difficult to distinguish between 132°E and 136°E, since the former combined with the latter to form a continuous equator‐tilted current. At ~137°E, the EUC axis started turning toward the equator, and an isolated EUC core was observed at 143°E and ~200‐m depth. The Pacific EUC was shown to originate at ~130°E, where it featured an isolated current core with a maximum velocity of 5–10 cm/s at ~1°N and 200‐ to 400‐m depth. The EUC and NECC in the western tropical Pacific were found to have the same water sources, namely, the MC and the New Guinea Coastal Undercurrent, with the shallow parts (centered at ~100‐m depth) of MC and New Guinea Coastal Undercurrent finally reaching the NECC and their deeper parts (centered at ~200‐m depth) finally reaching the EUC.
Physical Determinants and Reduced Models of the Rapid Cooling of Urban Surfaces During Rainfall
Authors: Omidvar Hamidreza , Bou‐Zeid Elie , Chiaramonte Maurizio
Published: March 2019

Using a detailed model, sensitivity analyses are conducted to identify the leading physical determinants and heat fluxes that control energy exchange between surface runoff and urban pavements during rainfall. These analyses confirm that pavement characteristics, such as albedo and thermal effusivity, strongly influence the initial temperature of the pavement before rain starts. Moreover, this sensitivity propagates to the runoff and pavement temperatures as well as to sensible heat and evaporation fluxes during and after rainfall. Heat transfer inside the runoff and pavement during rainfall is also very sensitive to the rain temperature and is the leading process in surface cooling (the classically important sensible and latent heat fluxes to the atmosphere are minor contributors). Finally, based on the findings from the sensitivity analyses, using a bulk energy approach, a reduced version of the full model is proposed. This simple model uses the spatially averaged temperatures of the runoff and pavement and can predict their temperatures and the associated energy fluxes almost as accurately as the full model. The reduced model has the added advantages of computational efficiency and simplicity of implementation in coarse earth system models.
Ozone Pollution Deaths in India Higher Than Previously Thought
Authors: Underwood Emily
Published: March 2019

Reducing emissions could avert more than 300,000 deaths per year by 2050.
Congressional Task Force Outlines Its Approach to Climate Change
Authors: Showstack Randy
Published: March 2019

The Green New Deal created space to talk about market-based innovation, investment, and business and defense approaches, says a cochair of the New Democrat Coalition’s Climate Change Task Force.
Publisher Correction: Federated discovery and sharing of genomic data using Beacons
Authors: Fiume Marc , Cupak Miroslav , Keenan Stephen , Rambla Jordi , de la Torre Sabela , Dyke Stephanie O. M. , Brookes Anthony J. , Carey Knox , Lloyd David , Goodhand Peter , Haeussler Maximilian , Baudis Michael , Stockinger Heinz , Dolman Lena , Lappalainen Ilkka , Törnroos Juha , Linden Mikael , Spalding J. Dylan , Ur-Rehman Saif , Page Angela , Flicek Paul , Sherry Stephen , Haussler David , Varma Susheel , Saunders Gary , Scollen Serena
Published: March 2019

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
micro-RNAs dependent regulation of DNMT and HIF1α gene expression in thrombotic disorders
Authors: Vijay Aatira , Jha Prabhash Kumar , Garg Iti , Sharma Manish , Ashraf Mohammad Zahid , Kumar Bhuvnesh
Published: March 2019

MicroRNAs (miRNAs) are involved in a wide variety of cellular processes and post-transcriptionally regulate several mechanism and diseases. However, contribution of miRNAs functioning during hypoxia and DNA methylation together is less understood. The current study was aimed to find a shared miRNAs signature upstream to hypoxia (via HIF gene family members) and methylation (via DNMT gene family members). This was followed by the global validation of the hypoxia related miRNA signature using miRNA microarray meta-analysis of the hypoxia induced human samples. We further concluded the study by looking into thrombosis related terms and pathways enriched during protein-protein interaction (PPI) network analysis of these two sets of gene family. Network prioritization of these shared miRNAs reveals miR-129, miR-19band miR-23b as top regulatory miRNAs. A comprehensive meta-analysis of microarray datasets of hypoxia samples revealed 29 differentially expressed miRNAs. GSEA of the interacting genes in the DNMT-HIF PPI network indicated thrombosis associated pathways including “Hemostasis”, “TPO signaling pathway” and “angiogenesis”. Interestingly, the study has generated a novel database of candidate miRNA signatures shared between hypoxia and methylation, and their relation to thrombotic pathways, which might aid in the development of potential therapeutic biomarkers.
Hemodynamic responses to emotional speech in two-month-old infants imaged using diffuse optical tomography
Authors: Shekhar Shashank , Maria Ambika , Kotilahti Kalle , Huotilainen Minna , Heiskala Juha , Tuulari Jetro J. , Hirvi Pauliina , Karlsson Linnea , Karlsson Hasse , Nissilä Ilkka
Published: March 2019

Emotional speech is one of the principal forms of social communication in humans. In this study, we investigated neural processing of emotional speech (happy, angry, sad and neutral) in the left hemisphere of 21 two-month-old infants using diffuse optical tomography. Reconstructed total hemoglobin (HbT) images were analysed using adaptive voxel-based clustering and region-of-interest (ROI) analysis. We found a distributed happy > neutral response within the temporo-parietal cortex, peaking in the anterior temporal cortex; a negative HbT response to emotional speech (the average of the emotional speech conditions < baseline) in the temporo-parietal cortex, neutral > angry in the anterior superior temporal sulcus (STS), happy > angry in the superior temporal gyrus and posterior superior temporal sulcus, angry < baseline in the insula, superior temporal sulcus and superior temporal gyrus and happy < baseline in the anterior insula. These results suggest that left STS is more sensitive to happy speech as compared to angry speech, indicating that it might play an important role in processing positive emotions in two-month-old infants. Furthermore, happy speech (relative to neutral) seems to elicit more activation in the temporo-parietal cortex, thereby suggesting enhanced sensitivity of temporo-parietal cortex to positive emotional stimuli at this stage of infant development.