bluuebunny/crossref_metadata_2025 huggingface dataset:
Bridging the HIV treatment gap in Nigeria: examining community antiretroviral treatment models
Authors: Oladele Edward A , Badejo Okikiolu A , Obanubi Christopher , Okechukwu Emeka F , James Ezekiel , Owhonda Golden , Omeh Onuche I , Abass Moyosola , Negedu‐Momoh Olubunmi R , Ojehomon Norma , Oqua Dorothy , Raj‐Pandey Satish , Khamofu Hadiza , Torpey Kwasi
Published: April 2018

Introduction

Significant gaps persist in providing HIV treatment to all who are in need. Restricting care delivery to healthcare facilities will continue to perpetuate this gap in limited resource settings. We assessed a large‐scale community‐based programme for effectiveness in identifying people living with HIV and linking them to antiretroviral treatment.

Methods

A retrospective secular trend study of 14 high burden local government areas of Nigeria was conducted in which two models of community antiretroviral treatment delivery were implemented: Model A (on‐site initiation) and Model B (immediate referral) clusters. Model A cluster offered services within communities, from HIV diagnosis to immediate antiretroviral therapy initiation and some follow‐up. Model B cluster offered services for HIV diagnosis up to baseline evaluation and provided referral for antiretroviral therapy initiation to nearest health facility providing HIV services. For controls, we selected and cluster‐matched 34 local government areas where community antiretroviral treatment delivery was not implemented. Outcomes of interest were: the number of people identified as HIV positive and the number of HIV‐positive individuals started on antiretroviral treatment; from June 2014 to May 2016. We used interrupted time‐series analysis to estimate outcome levels and trends across the pre‐and post‐intervention periods.

Results

Before community antiretrovial treatment introduction, Model A cluster identified, per 100,000 catchment population, 500 HIV‐positives (95% CI: 399.66 to 601.41) and initiated 216 HIV‐positives on antiretroviral treatment (95% CI: 152.72 to 280.10). Model B cluster identified 32 HIV‐positives (95% CI: 25.00 to 40.51) and initiated 8 HIV‐positives on antiretroviral treatment (95% CI: 5.54 to 10.33). After commART introduction, Model A cluster showed an immediate significant increase in 744 HIV‐positive persons (p = 0.00, 95% CI: 360.35 to 1127.77) and 560 HIV‐positives initiated on treatment (p = 0.00, 95% CI: 260.56 to 859.64). Model B cluster showed an immediate significant increase in 30 HIV‐positive persons identified (p = 0.01, 95% CI: 8.38 to 51.93) but not in the number of HIV‐positives initiated on treatment. Model B cluster showed increased month‐on‐month trends of both outcomes of interest (3.4, p = 0.02, 95% CI: 0.44 to 6.38).

Conclusion

Both community‐models had similar population‐level effectiveness for rapidly identifying people living with HIV but differed in effectively transitioning them to treatment. Comprehensiveness, integration and attention to barriers to care are important in the design of community antiretroviral treatment delivery.
Differentiation of brain infection from necrotic glioblastoma using combined analysis of diffusion and perfusion MRI
Authors: Chawla Sanjeev , Wang Sumei , Mohan Suyash , Nasrallah MacLean , Verma Gaurav , Brem Steven , O'Rourke Donald M. , Wolf Ronald L. , Poptani Harish , Nabavizadeh S. Ali
Published: April 2018

Background

Accurate differentiation of brain infections from necrotic glioblastomas (GBMs) may not always be possible on morphologic MRI or on diffusion tensor imaging (DTI) and dynamic susceptibility contrast perfusion‐weighted imaging (DSC‐PWI) if these techniques are used independently.

Purpose

To investigate the combined analysis of DTI and DSC‐PWI in distinguishing brain injections from necrotic GBMs.

Study Type

Retrospective.

Population

Fourteen patients with brain infections and 21 patients with necrotic GBMs.

Field Strength/Sequence

3T MRI, DTI, and DSC‐PWI.

Assessment

Parametric maps of mean diffusivity (MD), fractional anisotropy (FA), coefficient of linear (CL), and planar anisotropy (CP) and leakage corrected cerebral blood volume (CBV) were computed and coregistered with postcontrast T1‐weighted and FLAIR images. All lesions were segmented into the central core and enhancing region. For each region, median values of MD, FA, CL, CP, relative CBV (rCBV), and top 90th percentile of rCBV (rCBVmax) were measured.

Statistical Tests

All parameters from both regions were compared between brain infections and necrotic GBMs using Mann–Whitney tests. Logistic regression analyses were performed to obtain the best model in distinguishing these two conditions.

Results

From the central core, significantly lower MD (0.90 × 10−3 ± 0.44 × 10−3 mm2/s vs. 1.66 × 10−3 ± 0.62 × 10−3 mm2/s, P = 0.001), significantly higher FA (0.15 ± 0.06 vs. 0.09 ± 0.03, P < 0.001), and CP (0.07 ± 0.03 vs. 0.04 ± 0.02, P = 0.009) were observed in brain infections compared to those in necrotic GBMs. Additionally, from the contrast‐enhancing region, significantly lower rCBV (1.91 ± 0.95 vs. 2.76 ± 1.24, P = 0.031) and rCBVmax (3.46 ± 1.41 vs. 5.89 ± 2.06, P = 0.001) were observed from infective lesions compared to necrotic GBMs. FA from the central core and rCBVmax from enhancing region provided the best classification model in distinguishing brain infections from necrotic GBMs, with a sensitivity of 91% and a specificity of 93%.

Data Conclusion

Combined analysis of DTI and DSC‐PWI may provide better performance in differentiating brain infections from necrotic GBMs.

Level of Evidence: 1

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;49:184–194.
Levator Avulsion Is Associated With Pelvic Organ Prolapse 23 Years After the First Childbirth
Authors: Atan Ixora Kamisan , Lin Sylvia , Dietz Hans P. , Herbison Peter , Wilson Peter D. ,   for the ProLong Study Group
Published: April 2018

Objectives

This study aimed to ascertain the association between levator avulsion and pelvic organ prolapse (POP).

Methods

This was a cross‐sectional study involving 195 women enrolled in a longitudinal cohort study and seen 20 years after an index birth. All had a standardized patient‐administered questionnaire, the International Continence Society Pelvic Organ Prolapse Quantification assessment and 4D translabial ultrasound. Main outcome measures were objective POP clinically and on translabial ultrasound. Postimaging assessment of levator integrity and sonographically determined pelvic organ descent was done blinded against other data.

Results

Of 195 women who were seen a mean of 23 (range, 19.4–46.2) years after their first birth, one declined ultrasound assessment and was excluded, leaving 194. Mean age was 50.2 (range 36.9–66.5) years with a mean body mass index (BMI) of 27.6 (range, 18.3–54.3) kg/m2. Median parity was 3 (range 1–14). Ninety‐one percent (n = 176) had delivered vaginally. Eighteen percent (n = 34) were symptomatic of prolapse. Clinically, 36% (n = 69) had significant POP. Levator avulsion was diagnosed in 16% (n = 31). Mean levator avulsion defect score was 2.2 (range, 0–12). On univariate analysis, levator avulsion and levator avulsion defect score were associated with clinically and sonographically significant POP, that is, odds ratio 2.6 (1.2–5.7), P = .01; and odds ratio 3.3 (1.4–7.7); P = .003, respectively; Ba (P < .001); bladder (P < .001); uterine (P < .001) and rectal ampulla (P = .009) descent, but not POP symptoms, C, and Bp. Multivariate analysis controlling for potential confounders confirmed our findings.

Conclusions

Levator avulsion is associated with female pelvic organ prolapse, especially of the anterior and central compartments. This association may become stronger with aging.
Light may have triggered a period of net heterotrophy in Lake Superior
Authors: Brothers Soren , Sibley Paul
Published: April 2018

Recent studies of Lake Superior, the Earth's largest freshwater lake by surface area, describe it as net heterotrophic (primary production < community respiration), making it a net source of carbon dioxide (CO2) to the atmosphere. This conclusion is largely based on measurements made between 1998 and 2001. We present a long‐term (1968–2016) analysis of ice‐free (April–November) surface oxygen (O2) saturation data collected by monitoring agencies. These data indicate that Lake Superior's surface waters are typically supersaturated with dissolved O2 from May to September (May–September mean is 103.5% ± 0.6%; pooled mean from April, October, and November is 97.6% ± 1.1%, standard error of the mean). However, these data also support prior studies which describe a state of net heterotrophy from 1998 to 2001. We investigated potential triggers for a transient heterotrophic period and discuss the sources of organic carbon necessary to fuel net heterotrophy in a large oligotrophic lake. We conclude that net heterotrophy likely resulted from an increase in light period and penetration driven by declines in cloud cover, increases in water clarity, and a reduction of winter ice cover following the 1997–1998 El Niño. Together, these could have depleted a pre‐existing pool of dissolved organic carbon (DOC) via photomineralization and/or photochemical degradation. Our results indicate that Lake Superior is typically net autotrophic (calculated annual CO2 influx = ∼ 0.4 Tg C). These results highlight how water clarity and aquatic DOC pools may interact to induce net metabolic shifts in large oligotrophic aquatic ecosystems.
An alternative approach to conventional seepage meters: Buoy‐type seepage meter
Authors: Lee Bong‐Joo , Lee Ji‐Hoon , Kim Dong‐Hun
Published: April 2018

We propose a new type of seepage meter to allow sequential measurements of submarine groundwater discharge (SGD) rate and SGD‐driven chemical flux at a point on seawater and groundwater interface. The system works on the basis of Δh, the difference in head between groundwater and seawater at groundwater–seawater interface, and uses a vertical cylinder fixed to a buoy to derive groundwater outflow corresponding to Δh from the seepage meter chamber to the vertical cylinder. Laboratory tank tests showed that volumetric flow rate (Q) from the buoy‐type seepage meter (BSM) compared very well with conventional seepage meter (CSM). The linear relationship between Q measurements with the two methods is also statistically significant (R2 = 0.976). Two sample t‐test reveals that there is not a significant difference between means of Q measurements with the two methods. R2 values of linear regressions between volumetric flow rate (Q) and Δh are 0.993 with the BSM, and 0.972 with the CSM. Field tests with the BSM at Bangdu Bay of Jeju Island, Korea also show linear relationship (R2 = 0.86) between SGD flux and Δh, and SGD flux and SGD‐derived chemical fluxes are inversely related to tides. Both results of laboratory and field tests support that the proposed seepage meter can be an alternative to the conventional seepage meters for measuring SGD flux, and that it can be used to monitor temporal variations of SGD flux and SGD‐driven chemical fluxes simultaneously.
A New Family of Photoluminescent Polymers with Dual Chromophores
Authors: Hu Chenxi , Guo Zhaoyan , Ru Yue , Song Wenbo , Liu Zhenjie , Zhang Xiaohong , Qiao Jinliang
Published: April 2018

A new family of photoluminescent polymers with dual chromophores is prepared in this study by using poly(maleic anhydride‐alt‐vinyl acetate), acetone, and metal hydroxide. These polymers, which contain both bulky carboxylic ester groups and metal carboxylate groups, are found to be dual‐emission photoluminescent, with a blue luminescence excitation‐dependent group and a red luminescence excitation‐independent group. These photoluminescence polymers with a nonconjugated structure and dual chromophores also show characteristics of aggregation‐induced emission (AIE). The luminous intensities of the AIE fibers prepared using the polymers are found to increase after stretching, in contrast to traditional photoluminescent fibers with the aggregation‐caused quenching property. The study also finds that the stretched fibers can emit the three primary colors when irradiated by ultraviolet, blue, and green light.
In Vitro Mineralization Study of Chitosan/Carbon Nanotubes Scaffolds: Effect of Mineralization Cycles
Authors: Horn Marilia M. , Amaro Martins Virginia C. , De Guzzi Plepis Ana M.
Published: April 2018

In this study, bioactive scaffolds of chitosan/carbon nanotubes with calcium phosphate deposits with potential use in bone tissue regeneration were developed. Alternate mineralization processes using 1, 2, or 3 cycles are performed to investigate the nucleation of phosphate salts in the scaffolds. Characterization is carried out by thermogravimetry (TG), scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy (EDX), and X‐ray diffraction (XRD). TG curves confirmed that the number of mineralization cycles influence the amount of nucleated inorganic phosphate with an increase of up to 22%. As observed by SEM, the quantity and the size of pores decreased as a function of the number of mineralization cycles. The nucleated mineral is spherical in shape and with an average size of 0.73 ± 0.10 μm. An increase in the mineralization cycles promoted an increase in the quantity of calcium phosphate and the Ca/P ratio also showed dependence with the mineralization cycles. As observed by XRD, calcium phosphate deposited in scaffolds is calcium deficient hydroxyapatite. The crystallite size is estimated using the Sherreŕs equation as being of 15 ± 1 nm.
Pectin/Carboxymethylcellulose Films as a Potential Food Packaging Material
Authors: Šešlija Sanja , Nešić Aleksandra , Škorić Marija L. , Krušić Melina K. , Santagata Gabriella , Malinconico Mario
Published: April 2018

The present paper reports on pectin based films modified with carboxymethyl cellulose intended for food packaging. The films are prepared by solvent‐casting method with different carboxymethyl cellulose content and cross‐linker concentration (Ca2+ ions) in the presence of glycerol as a plasticizer. FT‐IR spectra of the prepared films propose that carboxyl group from pectin are mainly involved in interactions with CMC, whereas −OH groups are mainly involved in self‐associated hydrogen bonding of neat polymers. Further, an addition of carboxymethyl cellulose improved mechanical properties compared to pure pectin films, while TGA analysis confirmed satisfying thermal stability regarding their potential application as packaging material. Finally, water vapor permeability values are in the range of 1.32 × 10−7 up to 2.03 × 10−7 g/m h Pa.
Streptococcus endopeptidases promote HPV infection in vitro
Authors: Pavlova Sylvia I. , Wilkening Reid V. , Federle Michael J. , Lu Yu , Schwartz Joel , Tao Lin
Published: April 2018

Both cervical and throat cancers are associated with human papillomavirus (HPV). HPV infection requires cleavage of the minor capsid protein L2 by furin. While furin is present in the vaginal epithelium, it is absent in oral epithelial basal cells where HPV infection occurs. The objective of this study was to investigate whether common oral bacteria express furin‐like peptidases. By screening strains representing 12 oral Streptococcus and Enterococcus species, we identified that eight Streptococcus strains displayed high levels of furin‐like peptidase activity, with S. gordonii V2016 the highest. We constructed null mutations for 14 genes encoding putative endopeptidases in S. gordonii V2016. Results showed that three endopeptidases, PepO, PulO, and SepM, had furin‐like activities. All three mutants showed decreased natural transformation by chromosomal DNA, while the pepO mutant also showed reduced transformation by plasmid DNA, indicating involvement of these endopeptidases in competence development. The purified S. gordonii PepO protein promoted infection of epithelial 293TT cells in vitro by HPV16 pseudovirus. In conclusion, oral bacteria might promote HPV infection and contribute to HPV tissue tropism and subsequent carcinogenesis in the oral cavity and throat by providing furin‐like endopeptidases.
Cheating, facilitation and cooperation regulate the effectiveness of phage‐encoded exotoxins as antipredator molecules
Authors: Aijaz Iqbal , Koudelka Gerald B.
Published: April 2018

Temperate phage encoded Shiga toxin (Stx) kills the bacterivorous predator, Tetrahymena thermophila, providing Stx+ Escherichia coli with a survival advantage over Stx− cells. Although bacterial death accompanies Stx release, since bacteria grow clonally the fitness benefits of predator killing accrue to the kin of the sacrificed organism, meaning Stx‐mediated protist killing is a form of self‐destructive cooperation. We show here that the fitness benefits of Stx production are not restricted to the kin of the phage‐encoding bacteria. Instead, nearby “free loading” bacteria, irrespective of their genotype, also reap the benefit of Stx‐mediated predator killing. This finding indicates that the phage‐borne Stx exotoxin behaves as a public good. Stx is encoded by a mobile phage. We find that Stx‐encoding phage can use susceptible bacteria in the population as surrogates to enhance toxin and phage production. Moreover, our findings also demonstrate that engulfment and concentration of Stx‐encoding and susceptible Stx− bacteria in the Tetrahymena phagosome enhances the transfer of Stx‐encoding temperate phage from the host to the susceptible bacteria. This transfer increases the population of cooperating bacteria within the community. Since these bacteria now encode Stx, the predation‐stimulated increase in phage transfer increases the population of toxin encoding bacteria in the environment.
Measurement of large strain properties in calf muscles in vivo using magnetic resonance elastography and spatial modulation of magnetization
Authors: Tan Kristy , Jugé Lauriane , Hatt Alice , Cheng Shaokoon , Bilston Lynne E.
Published: April 2018

It is important to measure the large deformation properties of skeletal muscle in vivo in order to understand and model movement and the force‐producing capabilities of muscle. As muscle properties are non‐linear, an understanding of how the deformation state affects the measured shear moduli is also useful for clinical applications of magnetic resonance elastography (MRE) to muscle disorders. MRE has so far only been used to measure the linear viscoelastic (small strain) properties of muscles. This study aims to measure the shear moduli of human calf muscles under varying degrees of strain using MRE. Nine healthy adults (four males; age range, 25–38 years) were recruited, and the storage modulus G′ was measured at three ankle angle positions: P0 (neutral), P15 (15° plantarflexed) and P30 (30° plantarflexed). Spatial modulation of magnetization (SPAMM) was used to measure the strain in the calf associated with the ankle rotations between P0 to P15 and P0 to P30. SPAMM results showed that, with plantarflexion, there was a shortening of the medial gastrocnemius and soleus muscles, which resulted in an expansion of both muscles in the transverse direction. Strains for each ankle rotation were in the range 3–9% (in compression). MRE results showed that this shortening during plantarflexion resulted in a mean decrease in G′ in the medial gastrocnemius (p = 0.013, linear mixed model), but not in the soleus (p = 0.47). This study showed that MRE is a viable technique for the measurement of large strain deformation properties in vivo in soft tissues by inducing physiological strain within the muscle during imaging.
Voids formation and their effects on mechanical properties in thermoformed carbon fiber fabric‐reinforced composites
Authors: Jiang Wei , Huang Zhigao , Wang Yunming , Zheng Bing , Zhou Huamin
Published: April 2018

Carbon fiber fabric‐reinforced polycarbonate composites with different processing parameters were fabricated by thermoforming process. Effects of processing conditions on volume fraction, spatial distribution, geometrical shape and size of voids were investigated with the aid of X‐ray computed tomography and microscopy observation. Regardless of holding pressure or dwell time, voids exhibited similar shape and size and were mainly concentrated in interlaminar zone. Meanwhile, three‐point bending test and short‐beam strength test were performed to evaluate the effects of the void content on mechanical properties. The flexural strength and modulus significantly reduced with only a small amount of void content increase, which decreased by about 23 MPa and 2.17 GPa for each rise of 1% in void content, respectively. The relationship between the voids and interlaminar shear property was also established and a suitable processing window was gained. POLYM. COMPOS., 40:E1094–E1102, 2019. © 2018 Society of Plastics Engineers
Predictors of Mainland Chinese students’ well‐being
Authors: Skrzypiec Grace , Askell‐Williams Helen , Zhao Xueqin , Du Wenping , Cao Fei , Xing Lihong
Published: April 2018

There has been substantial research in the United States, Europe, and Australia about factors influencing students’ well‐being. However, such research has been relatively rare in Mainland China. We administered four predictor scales (School Satisfaction, Self‐Concept, Relationships, and Resilience) and three outcome scales (Flourishing, Mental Health, and Children's Well‐Being) to 2,756 primary and middle school students in Mainland China. Confirmatory factor analysis indicated that the measured concepts were salient to the participants. Structural equation modeling using MPlus showed that Resilience was a strong predictor of all outcome measures, particularly for Mental Health and Positive Emotional State. Global Self‐Concept was the most notable predictor for Positive Outlook, whereas School Satisfaction was the strongest predictor of Flourishing. The results indicate potential areas for school‐based competency‐building initiatives to promote Mainland Chinese students’ well‐being.
Optimization of bioreducible micelles self‐assembled from amphiphilic hyperbranched block copolymers for drug delivery
Authors: Yang Huiru , Zhao Xuezhi , Zhang Xiaolong , Ma Liwei , Wang Baoyan , Wei Hua
Published: April 2018

Dendritic polymers‐based unimolecular micelles with enhanced stability are attractive carriers. However, the preparation of dendrimers or dendrons with higher generation remains substantially synthetic challenge due to the increased steric hindrance, multistep and tedious preparation, and low yields. The adoption of Boltorn H40, a commercially available dendritic polymer of Boltorn family containing multiple hydroxyl groups with various functionalities as a dendrimer‐based starting core template for the generation of hyperbranched polymers, offers a straightforward solution to address this problem. To develop universal strategies toward H40‐based amphiphilic block copolymers, the “grafting from” and “grafting to” approaches were both applied in this study. The reduction‐insensitive block copolymers, H40‐b‐poly(ɛ‐caprolactone)‐b‐poly(oligo(ethylene glycol) monomethyl ether methacrylate) (H40‐b‐PCL‐b‐POEGMA), were synthesized by “grafting from” including sequential ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP). The core structure and the polymer composition of the nonreducible amphiphilic hyperbranched block copolymers were optimized toward better properties and performance for drug delivery applications, and H40‐PCL15‐b‐POEGMA23 was screened as the best polymer construct relative to H20‐PCL15‐b‐POEGMA23 and H40‐PCL15‐b‐POEGMA32 in terms of micelle stability and drug loading capacity. Therefore, the reducible H40‐b‐PCL‐SS‐POEGMA with an identical core and polymer composition to that of H40‐PCL15‐b‐POEGMA23 was further prepared by “grafting to” using click coupling between H40‐PCL‐azide and P(OEGMA)‐alkyne. The delivery efficacy evaluated by an in vitro cytotoxicity study revealed that the resulting DOX‐loaded reducible micelles of H40‐PCL15‐SS‐POEGMA23 produced greater cytotoxicity in cancer cells than in normal cells and macrophages, therefore, are promising carriers for anticancer drug delivery. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1383–1394
Disulfide‐centered poly(methyl acrylates): Four different stimuli to cleave a polymer
Authors: Fritze Urs F. , Craig Stephen L. , von Delius Max
Published: April 2018

A series of poly(methyl acrylates) incorporating a disulfide center was subjected to four different stimuli to cleave the SS bond, as the weakest member of the chain. Four polymers with molecular weights in the range of 25–93 kDa were synthesized via Cu‐based atom transfer radical polymerization starting from a difunctionalized disulfide‐containing initiator. In tetrahydrofuran, the labile disulfide center was cleaved directly by mechanical force generated by ultrasound irradiation, whereas in chloroform, competing cleavage was also triggered by radical species that were generated by non‐mechanical sonolysis. A reductive cleavage was observed upon treatment with reducing agent, and a clean reversal of the cleavage via oxidation could be obtained if the terminal bromide was first removed via hydrogenolysis. This modified polymer allowed studies on a fourth strategy for the cleavage of the disulfide, namely, dynamic covalent exchange reactions with a fluorine labeled small molecule. While partially based on established protocols, this comparative study underscores the versatility of the disulfide bond for applications in stimuli‐responsive and adaptive materials. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1404–1411
iProtGly‐SS: Identifying protein glycation sites using sequence and structure based features
Authors: Islam Md Mofijul , Saha Sanjay , Rahman Md Mahmudur , Shatabda Swakkhar , Farid Dewan Md , Dehzangi Abdollah
Published: April 2018

Glycation is chemical reaction by which sugar molecule bonds with a protein without the help of enzymes. This is often cause to many diseases and therefore the knowledge about glycation is very important. In this paper, we present iProtGly‐SS, a protein lysine glycation site identification method based on features extracted from sequence and secondary structural information. In the experiments, we found the best feature groups combination: Amino Acid Composition, Secondary Structure Motifs, and Polarity. We used support vector machine classifier to train our model and used an optimal set of features using a group based forward feature selection technique. On standard benchmark datasets, our method is able to significantly outperform existing methods for glycation prediction. A web server for iProtGly‐SS is implemented and publicly available to use: http://brl.uiu.ac.bd/iprotgly-ss/.
Eukaryote specific folds: Part of the whole
Authors: Kauko Anni , Lehto Kirsi
Published: April 2018

The origin of eukaryotes is one of the central transitions in the history of life; without eukaryotes there would be no complex multicellular life. The most accepted scenarios suggest the endosymbiosis of a mitochondrial ancestor with a complex archaeon, even though the details regarding the host and the triggering factors are still being discussed. Accordingly, phylogenetic analyses have demonstrated archaeal affiliations with key informational systems, while metabolic genes are often related to bacteria, mostly to the mitochondrial ancestor. Despite of this, there exists a large number of protein families and folds found only in eukaryotes. In this study, we have analyzed structural superfamilies and folds that probably appeared during eukaryogenesis. These folds typically represent relatively small binding domains of larger multidomain proteins. They are commonly involved in biological processes that are particularly complex in eukaryotes, such as signaling, trafficking/cytoskeleton, ubiquitination, transcription and RNA processing, but according to recent studies, these processes also have prokaryotic roots. Thus the folds originating from an eukaryotic stem seem to represent accessory parts that have contributed in the expansion of several prokaryotic processes to a new level of complexity. This might have taken place as a co‐evolutionary process where increasing complexity and fold innovations have supported each other.
Bayesian probability of predictive agreement for comparing the outcome of two separate regressions
Authors: Stevens Nathaniel T. , Rigdon Steven E. , Anderson‐Cook Christine M.
Published: April 2018

The concept of a Bayesian probability of agreement was recently introduced to give the posterior probabilities that the response surfaces for two different groups are within δ of one another. For example, a difference of less than δ in the mean response at fixed levels of the predictor variables might be thought to be practically unimportant. In such a case, we would say that the mean responses are in agreement. The posterior probability of this is called the Bayesian probability of agreement. In this article, we quantify the probability that new response observations from two groups will be within δ for a continuous response, and the probability that the two responses agree completely for categorical cases such as logistic regression and Poisson regression. We call these Bayesian comparative predictive probabilities, with the former being the predictive probability of agreement. We use Markov chain Monte Carlo simulation to estimate the posterior distribution of the model parameters and then the predictive probability of agreement. We illustrate the use of this methodology with three examples and provide a freely available R Shiny app that automates the computation and estimation associated with the methodology.
Fulfilling the 2(N+1)2 Hirsch rule in smaller hollow fullerenes. Evaluation of long‐range magnetic behavior and NMR patterns of C28, , C24N4, and C28H4
Authors: Muñoz‐Castro Alvaro
Published: April 2018

The formation of different 32 π‐electron systems derived from a prominent small fullerene given by C28, allows to evaluate several approaches ensuring an electronic shell closure in terms of the characteristic chemical shift anisotropy (CSA) and long‐range magnetic response properties for spherical aromatic compounds. Our results show that the inclusion of extra electrons and the doping of the cage, are able to sustain a long‐range shielding cone when an external field is oriented in a specific orientation. Such properties are inherent characteristics of spherical aromatic compounds, which are not obtained in the neutral C28 fullerene, and in the exo‐bonded approach leading to C28H4. Thus, the doping of the cage is suggested as the most suitable approach to modify the overall count of electrons, leading to the expected response properties for further design of highly aromatic fullerenes.
Central airway obstruction caused by adenoid cystic carcinoma in pregnancy: a case report and review of the literature
Authors: Shafiee Samaneh , Adno Alan , French Bruce , Johansson Cherynne , Frankel Anthony , Williamson Jonathan P.
Published: April 2018

Malignancy complicates one in a thousand pregnancies. The most frequently diagnosed of these are breast, cervical, melanoma, ovarian, and haematological neoplasms. Tumours of respiratory origin are very uncommon during pregnancy. We present a case of tracheal adenoid cystic carcinoma (ACC), a rare type of primary airway tumour, diagnosed in a pregnant woman. To our knowledge, this is the third reported case of tracheal ACC complicating pregnancy. We discuss potential barriers to timely diagnosis of malignancies during pregnancy and consider optimal management strategies, taking into account the potential harm to the mother and foetus in a field with a limited evidence base.
Lattice Vibration and Raman Scattering in Anisotropic Black Phosphorus Crystals
Authors: Mao Nannan , Zhang Shuqing , Wu Juanxia , Zhang Jin , Tong Lianming
Published: April 2018

Here, an overview of recent advances on the Raman spectroscopic studies of 2D black phosphorus (BP) crystals is provided, covering the fundamentals of Raman scattering such as the crystal symmetry and the assignment of the phonon modes, the Raman selection rule that can be used to determine the crystalline orientation, the interlayer coupling that gives rise to the interlayer shear and breathing modes, and the effects of perturbation such as temperature, strain, and pressure. Due to the low in‐plane symmetry of BP, particular attention is given to the anisotropic electron–photon and electron–phonon interactions in BP, which have strikingly distinct characteristics compared with other isotropic 2D materials. The abnormal polarized Raman scattering of anisotropic BP crystals and its dependence on the excitation energy, thickness, and phonon modes are discussed from the viewpoints of the complex Raman tensors and the optical birefringence effect. Furthermore, the calibration of the Raman selection rule in anisotropic BP crystals is discussed, and the versatility of Raman spectroscopy in characterizing the structure of BP, such as the layer number, the type of edges, and the crystalline orientation are considered.
Identification of Sybil attacks on social networks using a framework based on user interactions
Authors: Asadian Hooman , Javadi Hamid Haj Seyed
Published: April 2018

The popularity of modern social networks has rendered social media platforms vulnerable to malicious activities. One such activity is a Sybil attack, in which a single entity emulates the behaviors of multiple users and attempts to create problems for other users and a network itself. This problem has prompted researchers to develop several techniques for preventing Sybil attacks, but in most cases, the efficiency assumptions that underlie proposed methods are not oriented toward reality. The current study puts forward an efficient framework for identifying Sybil attacks. The highly precise framework is underlain by rational assumptions and detects attacks on the basis of the structural characteristics of social networks and the social interactions among users. We evaluate our proposed framework using both synthetic and real world social network topologies. We show that SybilUncover is able to accurately identify high precision rate. Moreover, SybilUncover performs orders of magnitudes better than existing Sybil detection mechanisms.
Conformational Analysis of Carboxymethylamylose by Potentiometric Titration and SAXS
Authors: Takada Masako , Wada Kaori , Muroga Yoshio , Ikake Hiroki , Shimizu Shigeru
Published: April 2018

Hydroxyl groups of amylose are barely dissociated into ions at pH lower than about 12, and so amylose is almost insoluble in neutral and acidic aqueous solutions and its conformation in solution has been a question under debate. Carboxymethylamylose (CMA) has much better solubility in aqueous solution than amylose and the conformation of CMA is expected to reflect that of the parent amylose. In the present study, CMA was prepared by substituting H of 24.5 mol.% hydroxyl groups of amylose with carboxymethyl groups, and the conformation of CMA in KI aqueous solution was studied as a function of the concentration of iodine I2 and the degree of ionization α by potentiometric titration. Different conformational behaviors were observed in different α domains: In a low‐α domain, CMA in KI/I2 aqueous solution and in KI aqueous solution behaves as a tightly‐wound helical chain and a loosely‐wound helical chain, respectively. The helical‐ and psedo‐helical‐chain are gradually collapsed to extended‐coils as α increases and CMA equally behaves as an extended‐coil in a medium‐α domain and as a more extended‐coil in a higher‐α domain. Such a conformational change was reflected in a change of persistence length of a chain with α, which was clarified by small‐angle X‐ray scattering study.
Comparison of wavelength‐dispersive X‐ray fluorescence spectrometry and inductively coupled plasma optical emission spectrometry for the elementary determination in plants through the accuracy profile method
Authors: Masson Pierre , Dalix Thierry , Daugey Guillaume , Soulé Patrice
Published: April 2018

Accuracy profile is a graphical method, which allows to validate an analytical method. It defines a validity of a concentration range for a given accuracy. With this tool, quantitative determinations of macroelements and microelements (Al, Ca, Fe, K, Mg, Mn, Na, P, S, and Zn) in plant samples were evaluated by the use of a wavelength‐dispersive X‐ray fluorescence instrument. The method uses a simple preparation procedure with only drying, grinding, and pressing samples. The measured samples were reference materials with known mineral contents. The calibration procedure was established by employing plant materials issued from interlaboratory studies. Matrix effects were corrected by employing the method of the influence coefficients on the basis of the computerized routine program linked to the equipment. The accuracy profiles of the method show the measurements (trueness and precision) collected under intermediate precision conditions and aim to compute an acceptability interval where a known proportion of future results will be located. The various types of accuracy profile behavior were exemplified. In comparison with an inductively coupled plasma optical emission spectrometry method, the use of X‐ray fluorescence offers a good alternative, faster, and better precision. Inversely, inductively coupled plasma optical emission spectrometry offers an approach well suited for the trueness of measurements with very low matrix effects.
Order-theoretic properties and separability of some sets of quasi-measures
Authors: Lipecki Zbigniew
Published: April 2018

Let

$${{\mathfrak {M}}}$$

M

and

$${{\mathfrak {R}}}$$

R

be algebras of subsets of a set

$$\Omega $$

Ω

with

$${\mathfrak {M}}\subset {\mathfrak {R}}$$

M
⊂
R

. Denote by

$$E(\mu )$$

E
(
μ
)

the set of all quasi-measure extensions of a given quasi-measure

$$\mu $$

μ

on

$${\mathfrak {M}}$$

M

to

$${\mathfrak {R}}$$

R

. We present some results on the coincidence of the bands, in

$${\mathfrak {R}}$$

R

, generated by

$$E(\mu )$$

E
(
μ
)

and extr

$$E(\mu )$$

E
(
μ
)

. Moreover, we show that if

$$\mu $$

μ

is atomic, then

$$E(\mu )$$

E
(
μ
)

is contained in a principal band in

$${\mathfrak {R}}$$

R

if and only if it is separable. Another sufficient condition for the separability of

$$E(\mu )$$

E
(
μ
)

is also presented.
Impact of Environmental Education on Beginning Preservice Teachers’ Environmental Literacy
Authors: Dada Deborah O. , Eames Chris , Calder Nigel
Published: April 2018

One of the goals of environmental education is the development of environmental literacy. The development of environmental literacy for preservice teachers is critical if they are to be confident and competent to deliver environmental education in schools. Little is known about the impact of environmental education on preservice teachers’ environmental literacy and their subsequent practices as teachers within schools in New Zealand. This study used a mixed-methods approach with a pretest and posttest design to examine the environmental literacy of preservice teachers enrolled in a compulsory environmental education paper as part of their Bachelor of Teaching program at a New Zealand university. The perceptions of the preservice teachers’ preparedness to teach environmental education was also examined. Findings indicate that despite only slight shifts in preservice teachers’ environmental literacy, their confidence to teach environmental education significantly increased after completing the paper. Increases in the strength of correlations between environmental knowledge and affective dispositions were observed upon completing the environmental education paper. Implications of findings for teacher education programs are discussed. This study could inform curriculum design and teaching and learning practices for effectively preparing preservice teachers to promote the development of the environmental literacy of students in their future schools.
A Sea Country Learning Partnership in Times of Anthropocenic Risk: Offshore Coral Reef Education and Our Story of Practice
Authors: Whitehouse Hilary , Taylor Marie , Evans Neus (Snowy) , Doyle Tanya , Sellwood Juanita , Zee Ruth
Published: April 2018

This is a researched account of an offshore coral reef education partnership formed during a time of rapid environmental change (the coral bleaching events in the years 2015 to 2017). The aim of the partnership is to encourage a learning connection with Sea Country. Framed as civic environmentalism, this article explores the dimensions of practice between a reef tourism provider, local schools, a local university, and local Indigenous rangers that enables primary, secondary and university students, rangers, and educators to travel together on day trips to the outer Great Barrier Reef and islands and have immersive and sharing educational experiences. Offshore environmental education and higher quality marine education is increasingly important in the Anthropocene, when Australian reefs are subject to the pressures of climate change and other impacts other impacts that diminish their resilience.
Decay of plane detonation waves to the self-propagating Chapman–Jouguet regime
Authors: Clavin Paul , Denet Bruno
Published: April 2018

A theoretical study of the decay of plane gaseous detonations is presented. The analysis concerns the relaxation of weakly overdriven detonations toward the Chapman–Jouguet (CJ) regime when the supporting piston is suddenly arrested. The initial condition concerns propagation velocities ${\mathcal{D}}$ that are not far from that of the CJ wave ${\mathcal{D}}_{CJ}$, $0<({\mathcal{D}}/{\mathcal{D}}_{CJ}-1)\ll 1$. The unsteady inner structure of the detonation wave is taken into account analytically for small heat release, i.e. when the propagation Mach number of the CJ wave $M_{u_{CJ}}$ is small, $0<(M_{u_{CJ}}-1)\ll 1$. Under such conditions the flow is transonic across the inner structure. Then, with small differences between heat capacities (Newtonian limit), the problem reduces to an integral equation for the velocity of the lead shock. This equation governs the detonation dynamics resulting from the coupling of the unsteady inner structure with the self-similar dynamics of the centred rarefaction wave in the burnt gas. The key point of the asymptotic analysis is that the response time of the inner structure is larger than the reaction time. How, and to what extent, the result is relevant for real detonations is discussed in the text. In a preliminary step the steady-state approximation is revisited with particular attention paid to the location of the sonic condition.
Neutral stability curves of low-frequency Görtler flow generated by free-stream vortical disturbances
Authors: Viaro Samuele , Ricco Pierre
Published: April 2018

The neutral curves of the boundary layer Görtler-vortex flow generated by free-stream disturbances, i.e., curves that distinguish the perturbation flow conditions of growth and decay, are computed through a receptivity study for different Görtler numbers, wavelengths, and low frequencies of the free-stream disturbance. The perturbations are defined as Klebanoff modes or strong and weak Görtler vortices, depending on their growth rate. The critical Görtler number below which the inviscid instability due to the curvature never occurs is obtained and the conditions for which only Klebanoff modes exist are thus revealed. A streamwise-dependent receptivity coefficient is defined and we discuss the impact of the receptivity on the $N$-factor approach for transition prediction.
Dietary minerals, reproductive hormone levels and sporadic anovulation: associations in healthy women with regular menstrual cycles
Authors: Kim Keewan , Wactawski-Wende Jean , Michels Kara A. , Schliep Karen C. , Plowden Torie C. , Chaljub Ellen N. , Mumford Sunni L.
Published: April 2018

Although minerals are linked to several reproductive outcomes, it is unknown whether dietary minerals are associated with ovulatory function. We hypothesised that low intakes of minerals would be associated with an increased risk of anovulation. We investigated associations between dietary mineral intake and both reproductive hormones and anovulation in healthy women in the BioCycle Study, which prospectively followed up 259 regularly menstruating women aged 18–44 years who were not taking mineral supplements for two menstrual cycles. Intakes of ten selected minerals were assessed through 24-h dietary recalls at up to four times per cycle in each participant. Oestradiol, progesterone, luteinising hormone (LH), follicle-stimulating hormone (FSH), sex-hormone-binding globulin and testosterone were measured in serum up to eight times per cycle. We used weighted linear mixed models to evaluate associations between minerals and hormones and generalised linear models for risk of anovulation. Compared with Na intake ≥1500 mg, Na intake <1500 mg was associated with higher levels of FSH (21·3 %; 95 % CI 7·5, 36·9) and LH (36·8 %; 95 % CI 16·5, 60·5) and lower levels of progesterone (−36·9 %; 95 % CI −56·5, −8·5). Na intake <1500 mg (risk ratio (RR) 2·70; 95 % CI 1·00, 7·31) and Mn intake <1·8 mg (RR 2·00; 95 % CI 1·02, 3·94) were associated with an increased risk of anovulation, compared with higher intakes, respectively. Other measured dietary minerals were not associated with ovulatory function. As essential minerals are mostly obtained via diet, our results comparing insufficient levels with sufficient levels highlight the need for future research on dietary nutrients and their associations with ovulatory cycles.
Why the ‘Politics’ against African Philosophy should be Discontinued
Authors: CHIMAKONAM JONATHAN O. , NWEKE VICTOR CLEMENT
Published: April 2018

We argue that philosophy education across the globe is still bedevilled with the ‘politics’ of marginalization of less favoured traditions like African philosophy. Extant works show that the conventional curriculum of philosophy used in educational institutions across the globe is predominantly Western and, as such, very much colonial. We contend that this amounts to a sort of ‘epistemic injustice’ that is detrimental to knowledge production. We argue specifically that this ‘politics’ should be discontinued. We propose the conversational tradition, out of which a philosophy curriculum that is comprehensive and antithetical to the politics of exclusion may be developed.
Reimagining Traitors: Pearl Abraham'sAmerican Talibanand the Case of John Walker Lindh
Authors: POPESCU MARIA-IRINA
Published: April 2018

Pearl Abraham's 2010 novelAmerican Talibanuses the “true” story of John Walker Lindh, a white US citizen captured fighting for the Taliban in Afghanistan in 2001, to reflect on the intense mediation of public trauma in the early days of the “War on Terror.” This article discusses the significance ofAmerican Talibanas a post-“9/11” work of literary fiction which, by imagining individual agency and interrogating the relationship between a racialized “Americanness,” treason and sovereignty, invites its readers to be critical of historical, political and media narratives in the so-called “post-truth era.”
Complicit Suffering and the Duty to Self-Care
Authors: LaGuardia-LoBianco Alycia W.
Published: April 2018

Moral questions surrounding suffering tend to focus on obligations to relieve others’ suffering. In this paper, I focus on the overlooked question of what sufferers morally owe to themselves, arguing that they have the duty to self-care. I discuss agents who have been shaped by moral luck to contribute to their own suffering and canvass the ways in which this damages their moral agency. I contend that these agents have a duty to care for themselves by protecting and expanding their agency, which involves precluding further destruction of agency and ensuring the continued ability to self-care.