bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrological pulses and burning of dissolved organic carbon by stream respiration
Authors: Demars Benoît O. L.
Published: October 2018

Stream metabolism plays a significant role in the global carbon cycle. Storm events can lower stream metabolic activities by removing standing biomass and river bed stock of organic matter. However, hydrological events could also stimulate stream ecosystem respiration (ER) by providing dissolved organic carbon (DOC) derived from soils. Here, I show how hydrological connectivity between land and water affects fluxes of DOC and daily whole stream bacterial respiration over an annual cycle in streams rich in DOC in north‐west Europe. The novelty of the approach resides in combining continuous whole stream metabolism with hydrological flow paths and water chemistry to quantify the in situ fate of DOC at ecosystem scale, with an estimation of all major stream carbon fluxes (land‐derived CO2, in‐stream biotic CO2, HCO3, and DOC) at catchment scale. An average 23% ± 11% of the annual DOC inputs from the land was respired away by benthic microbial metabolism within about an hour of transit time in small watersheds (about 1 km2). Stream ER was highly related to discharge and was stimulated for as long as the hydrological connectivity between land and water remained, as indicated by soil moisture continuous monitoring. In‐stream heterotrophic respiration represented 16% ± 7% of the annual total carbon fluxes (also including HCO3, land‐derived CO2, and DOC) at the catchment outlet under stable flows. This study suggests that DOC supply (soil carbon loss) will increase with rainfall, stimulating aquatic respiration, and CO2 emissions in streams.
Exploration of the Direct Arylation Polymerization Method for the Practical Application of Conjugated Materials: Synthetic Scale‐Up, Solar Cell Performance, and Cost Analyses
Authors: Pappenfus Ted M. , Almyahi Furqan , Cooling Nathan A. , Culver Evan W. , Rasmussen Seth C. , Dastoor Paul C.
Published: October 2018

This study reports the scalability of direct arylation polymerization (DArP) batch reactions for the preparation of poly(3‐hexylthiophene) (P3HT) using the Herrmann–Beller catalyst combined with a tertiary phosphine in the green solvent 2‐methyltetrahydrofuran on scales ranging from 0.5 to 10 g. The physical properties of these DArP polymers are compared to those resulting from P3HT prepared via Grignard metathesis (GRIM) on a 130 g scale. Both DArP and GRIM methods are found to produce highly regioregular polymers with no evidence of β‐defects and the polymers are found to exhibit comparable device performance as donor materials in bulk heterojunction organic solar cells. Purification studies coupled with device measurements highlight the necessity to carefully address the presence of impurities in materials produced from large‐scale DArP batch reactions. Economic analyses reveal that the cost involved in the preparation of P3HT via DArP or GRIM procedures are comparable per gram of product and show that the most expensive component is unique for each method.
Tuning the Phase Transition from UCST‐Type to LCST‐Type by Composition Variation of Polymethacrylamide Polymers
Authors: Käfer Florian , Pretscher Martin , Agarwal Seema
Published: October 2018

Polymethacrylamide copolymers with hydrophobic N‐substituted acrylamides, such as N‐cyclohexylacrylamide and N‐tert‐butylacrylamide, are rare examples of polymers showing composition‐dependent thermoresponsive behavior in water. They show unexpected behavior different from the conventional copolymers of a thermoresponsive polymer with hydrophobic comonomers. On increasing the amount of the hydrophobic comonomer in the polymer, there is a change from UCST‐type phase behavior to complete solubility, followed by compositions showing LCST‐type transition and insolubility in water (U‐S‐L‐I‐type change). At 50 mol% of less hydrophobic N‐tert‐butyl acrylamide (logP 0.87) in contrast to ≈25 mol% of N‐cyclohexylacrylamide (logP 1.51), the broad UCST‐type transition of polymethacrylamide is turned to LCST‐type transitions with very narrow hysteresis in water and PBS buffer. The use of H‐bond and water‐structure breaker showed the role of H‐bonding and hydrophobic interactions in phase transitions of UCST‐type and LCST‐type, respectively. This work is an important add‐on to the infant field of nonionic polymers of UCST‐type.
Prefrontal Cortical Stimulation in Tourette Disorder: Proof‐of‐concept Clinical and Neuroimaging Study
Authors: Perani Daniela , Lalli Stefania , Iaccarino Leonardo , Alongi Pierpaolo , Gambini Orsola , Franzini Angelo , Albanese Alberto
Published: October 2018

Background

The benefits of neurosurgery in Tourette Syndrome (TS) are still incompletely understood. Prefrontal cortical electrical stimulation offers a less invasive alternative to deep brain stimulation.

Objective

To perform a pilot assessment on safety and efficacy of prefrontal cortical bilateral electrical stimulation in TS using clinical and brain metabolic assessments.

Methods

Four adult TS patients underwent tic assessment using the Yale Global Tic Severity Scale and the Rush Video Rating Scale at baseline and 1, 3, 6, and 12‐months after implant; whereas FDG‐PET scans were acquired at baseline and after 6 and 12 months.

Results

Tic clinical scores were improved at 6 months after implant, meanwhile they showed a tendency to re‐emerge at the 12‐month follow‐up. There was a correlation between FDG‐PET and tics, mainly consisting in a reduction of baseline brain hypermetabolism, which paralleled tic score reduction.

Conclusion

Epidural stimulation in TS is safe and yields a modulation of tics, paralleled by FDG‐PET metabolic modulation.
Analysis of the second Piola‐Kirchhoff stress in nonlinear thick and thin structures using exact geometry SaS solid‐shell elements
Authors: Kulikov G. M. , Plotnikova S. V.
Published: October 2018

This paper presents the finite rotation exact geometry four‐node solid‐shell element using the sampling surfaces (SaS) method. The SaS formulation is based on choosing inside the shell N SaS parallel to the middle surface to introduce the displacements of these surfaces as basic shell unknowns. Such choice of unknowns with the consequent use of Lagrange polynomials of degree N–1 in the through‐thickness distributions of displacements, strains and stresses leads to a robust higher‐order shell formulation. The SaS are located at only Chebyshev polynomial nodes that make possible to minimize uniformly the error due to Lagrange interpolation. The proposed hybrid‐mixed four‐node solid‐shell element is based on the Hu‐Washizu variational principle and is completely free of shear and membrane locking. The tangent stiffness matrix is evaluated through efficient 3D analytical integration and its explicit form is given. As a result, the proposed exact geometry solid‐shell element exhibits a superior performance in the case of coarse meshes and allows the use of load increments, which are much larger than possible with existing displacement‐based solid‐shell elements.
Mismatch in Children’s Weight Assessment, Ideal Body Image, and Rapidly Increased Obesity Prevalence in China: A 10‐Year, Nationwide, Longitudinal Study
Authors: Min Jungwon , Fang Yan Alice , Wang Youfa
Published: October 2018

Objective

This study examined secular trends in children’s weight‐status assessment, measured weight status, and ideal body image and their associations with subsequent changes in BMI, and it explored the differences between sociodemographic groups in China.

Methods

Longitudinal data from the China Health and Nutrition Survey of 4,605 children aged 6 to 17 collected between 2000 and 2011 were used and fitted to mixed models.

Results

From 2000 to 2011, overweight/obesity prevalence increased from 6.5% to 16.8%, but the percentage of children with self‐perceived weight status as “fat” remained around 2.0%; 49.0% of children underestimated their weight status at baseline. Self‐perceived body image of most participants was tracked during follow‐up. Children who perceived themselves as being fat at baseline had a higher BMI increase over time during follow‐up than those with an average body image (β [SE] = 0.99 [0.14] kg/m2 per year, P < 0.001). Boys, young children, recent cohorts, and rural children had higher BMI increases than their counterparts. Over time, the thin‐body silhouette became more desirable (8.4 percentage points higher, P < 0.001).

Conclusions

Chinese children experience a large incongruence between their weight‐status assessment, ideal body image, and actual weight status. Health promotion programs should examine their role in assisting children in developing a healthy body image and gaining greater self‐motivation toward promoting a healthy lifestyle.
Genomic and transcriptomic characterisation of undifferentiated pleomorphic sarcoma of bone
Authors: Ali Naser M , Niada Stefania , Brini Anna T , Morris Mark R , Kurusamy Sathishkumar , Alholle Abdullah , Huen David , Antonescu Cristina R , Tirode Franck , Sumathi Vaiyapuri , Latif Farida
Published: October 2018

Undifferentiated pleomorphic sarcoma of bone (UPSb) is a rare primary bone sarcoma that lacks a specific line of differentiation. There is very little information about the genetic alterations leading to tumourigenesis or malignant transformation. Distinguishing between UPSb and other malignant bone sarcomas, including dedifferentiated chondrosarcoma and osteosarcoma, can be challenging due to overlapping features. To explore the genomic and transcriptomic landscape of UPSb tumours, whole‐exome sequencing (WES) and RNA sequencing (RNA‐Seq) were performed on UPSb tumours. All tumours lacked hotspot mutations in IDH1/2 132 or 172 codons, thereby excluding the diagnosis of dedifferentiated chondrosarcoma. Recurrent somatic mutations in TP53 were identified in four of 14 samples (29%). Moreover, recurrent mutations in histone chromatin remodelling genes, including H3F3A, ATRX and DOT1L, were identified in five of 14 samples (36%), highlighting the potential role of deregulated chromatin remodelling pathways in UPSb tumourigenesis. The majority of recurrent mutations in chromatin remodelling genes identified here are reported in COSMIC, including the H3F3A G34 and K36 hotspot residues. Copy number alteration analysis identified gains and losses in genes that have been previously altered in UPSb or UPS of soft tissue. Eight somatic gene fusions were identified by RNA‐Seq, two of which, CLTC‐VMP1 and FARP1‐STK24, were reported previously in multiple cancers. Five gene fusions were genomically characterised. Hierarchical clustering analysis, using RNA‐Seq data, distinctly clustered UPSb tumours from osteosarcoma and other sarcomas, thus molecularly distinguishing UPSb from other sarcomas. RNA‐Seq expression profiling analysis and quantitative reverse transcription‐polymerase chain reaction showed an elevated expression in FGF23, which can be a potential molecular biomarker for UPSb. To our knowledge, this study represents the first comprehensive WES and RNA‐Seq analysis of UPSb tumours revealing novel protein‐coding recurrent gene mutations, gene fusions and identifying a potential UPSb molecular biomarker, thereby broadening the understanding of the pathogenic mechanisms and highlighting the possibility of developing novel targeted therapeutics. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Thai version of the Functional Rating Index for patients with back and neck pain: Part II responsiveness and head‐to‐head comparisons
Authors: Chansirinukor Wunpen
Published: October 2018

Objectives

To examine responsiveness and estimate minimal clinically important difference (MCID) of the Thai version of Functional Rating Index (Thai FRI) and examine head‐to‐head comparisons of the Thai FRI and other questionnaires.

Methods

This study related to validation of a questionnaire and head‐to‐head comparisons. Patients with low back pain (LBP) completed the Thai FRI, Roland–Morris (RM), modified Oswestry, and multilevel RM disability questionnaires. Patients with neck pain (NP) completed the Thai FRI and Neck Disability Index at the first visit and 2‐week follow‐up. Patients and therapists rated Global Perceived Effect Scales (GPES). Effect size (ES), standardized response mean (SRM), correlations between the GPES with changes in questionnaire scores, and area under receiver operating characteristic curve (AUC) were calculated. The MCID was also estimated.

Results

Eighty‐four patients with LBP and 52 patients with NP completed the Thai FRI. ES = 1.34 for LBP; 1.28 for NP, SRM = 1.32 for LBP; 1.20 for NP, correlation = 0.49 for LBP; 0.38 for NP, AUC = 0.83 for both groups. MCID = 11.5 for LBP; 12.5 FRI points for NP.

Conclusion

The Thai FRI demonstrated responsiveness with large ES. Its MCID ranged from 11.5 to 12.5 FRI points. The Thai FRI had comparable responsiveness to other questionnaires and was appropriate for use in the patients with back and/or neck pain.
Synthesis and antifungal activities of novel thiophene‐based stilbene derivatives bearing an 1,3,4‐oxadiazole unit
Authors: Wen Lan , Jian Weilin , Shang Junbing , He Daohang
Published: October 2018

BACKGROUND

Natural stilbenes (especially resveratrol and its derivatives) are well‐known phytoalexins that are active against many plant diseases. However, oxidative degradation and low bioavailability limit their exogenous application as fungicides on crops. In this study, a new class of resveratrol‐inspired thiophene‐based stilbene derivatives bearing an 1,3,4‐oxadiazole unit was synthesized and the derivatives' antifungal activities against phytopathogenic fungi were investigated.

RESULTS

The results revealed that compounds 5h and 5j exhibited improved antifungal activity against Botrytis cinerea with median effective concentrations (EC50) of 168.5 and 155.4 µg mL−1, respectively, which were superior to the EC50 of resveratrol (263.1 µg mL−1). Compound 5j was shown to effectively control disease development in B. cinerea‐infected tomatoes in vivo. Notably, considerably abnormal mycelial morphology and increased cell membrane conductivity were observed in the presence of compound 5j.

CONCLUSION

A new class of thiophene‐containing stilbene derivatives was designed and synthesized. Bioassay results showed that compound 5j exhibited promising antifungal activity, suggesting practical potential for fungal disease control. © 2018 Society of Chemical Industry
Ba0.6Sr0.4TiO3 Thin Films Deposited by Spray Coating for High Capacitance Density Capacitors
Authors: Tetsi Emmanuel , Philippot Gilles , Bord Majek Isabelle , Aymonier Cyril , Audet Jean , Lemire Roxan , Bechou Laurent , Drouin Dominique
Published: October 2018

Metal‐insulator‐metal (MIM) capacitors with Ba0.6Sr0.4TiO3 (BST) thin films as insulating layers are fabricated using a novel, fast, and low‐cost method. On one hand, the process lies in the swift, continuous, and scalable synthesis of BST nanoparticles using the supercritical fluid technology and, on the other hand, the nonpyrolytic spray coating of thin films using colloidal nanocrystals as ink. The authors focus on the deposition process of thin and uniform layer. A dispersed colloidal suspension based on BST nanoparticles is deposited on a hot copper substrate. A 200 nm thick dielectric film is successfully obtained. Electrical characterizations of Cu/BST/Al MIM structure demonstrate a state‐of‐the‐art capacitance density almost reaching 1 µF cm−2 within an operating voltage range of ±1 V. Moreover, an annealing process of the dielectric layer and the final MIM capacitor at 90 °C during 15 h brings a significant decrease of the leakage current by three decades from mA cm−2 to µA cm−2.
Integrated fault estimation and fault‐tolerant control for uncertain time‐varying delay nonlinear Markovian jump systems
Authors: Qi Fucang , Ma Yuechao
Published: October 2018

This paper investigates the issues of fault estimation and fault‐tolerant control for a class of uncertain time‐varying delay nonlinear Markovian jump systems with simultaneous actuator and sensor faults. Firstly, by analyzing and reformulating the original system, a Markovian robust sliding‐mode observer is introduced to provide simultaneous estimations of the state and faults. Secondly, a novel stochastic integral sliding surface function is designed, and the sufficient criteria is derived in terms of linear matrix inequalities, which guarantees that the sliding‐mode dynamics and error system are asymptotically stable with definite appointed H∞ performance disturbance attenuation level. Then, a robust sliding‐mode control law scheme is sought to ensure the reachability of the sliding surface in a finite time interval. Finally, the effectiveness of the proposed methodology is verified by numerical and practical examples.
The limits of relational governance: Sales force strategies in the U.S. medical device industry
Authors: Chatterji Aaron K. , Cunningham Colleen M. , Joseph John E.
Published: October 2018

Research Summary: We explore how interorganizational relationships shape firm boundary decisions. Using data on 545 U.S. medical device manufacturers' product portfolios and sales‐governance choices (i.e., internal or external sales forces) from 1983 to 1996, we find relational capital between manufacturers and external sales forces influences future firm boundary decisions. Relational capital lowers the likelihood of integrating the sales function, but only when firms remain focused on the same product market. Further, launching an innovative product has a nuanced effect. For firms lacking relational capital, innovation increases the likelihood of sales integration. This pattern reverses as relational capital accumulates, but only when innovations are in the firm's existing focal product market. Our findings suggest important limits on the effect of relational governance on firm strategy.

Managerial Summary: Choosing between in‐house or external sales is a key strategic decision. In the medical device industry, this decision is particularly important because salespeople are conduits between R&D and customers. For firms who initially choose external sales, the trade‐off between maintaining existing links (via external sales) and developing new, direct relationships (by bringing sales in‐house) can change significantly as product portfolios change. Analyzing 545 U.S. medical device manufacturers from 1983 to 1996, we find that existing relationships with external sales forces reduce the likelihood of bringing sales in‐house, but only when firms remain in the same product market, such as orthopedic implants. When firms launch products in new markets, especially innovations, they are more likely to bring sales in‐house.
A modified PageRank algorithm for biological pathway ranking
Authors: Zhang Qingyang
Published: October 2018

Pathways are the functional building blocks of complex diseases such as cancer. Identifying disease‐associated pathways is of great importance to the development of novel therapeutics, as it provides functional insights into the pathogenesis of a disease. Existing methods for pathway ranking, however, are mostly based on an enrichment score assigned to each pathway independently, which could be biased by overlooking the interactions between pathways. In this paper, we consider a modification of Google's PageRank algorithm in order to fully incorporate the pathway dependencies into the pathway ranking. The proposed measurement is a trade‐off between two important aspects, namely, the phenotype–pathway association and pathway coexpression. We propose to use a projection correlation to quantify pathway coexpression, and a generalized R2 for phenotype–pathway association. Our simulation study on real pathways shows the competitive performance of the new measure compared with enrichment‐based analyses in pathway ranking.
Effects of hysteretic damping on the seismic performance of tuned mass dampers
Authors: Kiani Mahdi , Vaseghi Amiri Javad
Published: October 2018

A tuned mass damper (TMD) as a convenient passive device in average to tall buildings has limitations specifically against broad band seismic excitations. According to evidences from the literature, this drawback can be dominated by using nonlinear stiffness in TMDs; however, past studies did not explore this issue, and observations are not sufficient to reach a conclusion about seismic performance of nonlinear TMDs. This paper considers seismic performance of a nonlinear TMD developed by adding a martensitic shape memory alloy spring with significant stable features to conventional TMDs. To this end, single degree of freedom structures (from short to large periods) equipped with the nonlinear TMD are investigated subjected to set of ground motions, and through numerical analyses, effects of hysteretic damping and energy absorption capacity of the nonlinear TMD are examined. In addition, features of the proposed TMD configuration and effects of the excitation properties have been scrutinized through graphing frequency response curves by the arc length continuation method. Results indicate that the proposed configuration can make the nonlinear TMD robust against variations of the loading properties. Moreover, due to significant hysteretic damping of the shape memory alloy, spring seismic performance of the nonlinear TMD is better than conventional TMDs.
Undergraduate geoscience education research: Evolution of an emerging field of discipline‐based education research
Authors: Arthurs Leilani A.
Published: October 2018

Discipline‐based education research (DBER) conducted by faculty within geoscience departments can address identified needs in undergraduate geoscience education. This study explores the evolution of undergraduate geoscience education research (GER) from 1985 to 2016, primarily in terms of the types of published research and secondarily in terms of the insights this literature offers on the evolution of GER as a scholarly discipline. Stokes’ (1997) quadrant model of research types is used as a theoretical framework for the former and Kuhn's (1970) model of disciplinary paradigm for the latter. An exploratory sequential mixed‐methods approach to a systematic literature review of 1,760 articles is utilized. The period 1985–2000 is characterized by proto‐research as evidenced by the abundance of instructive and informational education articles rather than research articles. From 2000 to 2011, GER underwent a growth period characterized by the presence of applied, use‐inspired, and pure basic research. The period 2011–2016 appears to be a period of relative steady‐state conditions in the normalized number of GER publications per year. Existing gaps in knowledge about geoscience education, the evident unfamiliarity with education and social science research methodologies among authors of GER articles, and efforts to build consensus about what GER is and how to conduct it suggest that GER is preparadigmatic or at a low paradigm state. That is, GER is an immature discipline as far as the evolution of a discipline goes. A path forward is proposed for the continued evolutionary growth of GER. This study provides new perspectives on the emergence of GER as a discipline that can be used as a basis for studies on cross‐disciplinary DBER comparisons.
Thiazole derivatives‐functionalized polyvinyl chloride nanocomposites with photostability and antimicrobial properties
Authors: Gaballah Samir T. , Khalil Ahmed M. , Rabie Samira T.
Published: October 2018

Polyvinyl chloride (PVC) was modified via substitution reaction with 2‐aminothiazole and ethyl 2‐aminothiazole‐4‐carboxylate separately in the absence and in presence of silver (AgNPs) or copper (CuNPs) nanoparticles, using metal salts as precursors, in 3% (w/w) with respect to PVC. The functionalized PVC‐nanocomposites have been characterized via FTIR, 1HNMR spectroscopic analyses, in addition to the morphological investigation such as scanning (SEM) and transmission electron microscopy (TEM). Spectral data confirmed the introduction of the thiazole (ester) to the PVC backbone. TEM analysis showed that the sizes of the AgNPs and CuNPs have fallen in the range of 10–30 nm and 30–50 nm for the prepared nanocomposites, respectively. Evaluating the photostability of modified nanocomposites was estimated by following the extent of discoloration for UV‐irradiated samples colorimetrically in accordance with the irradiation time. The antimicrobial activity of the modified nanocomposites was explored against three Gram+ve bacteria (Bacillus subtilis, Staphylococcus aureus, and Streptococcus faecalis), three Gram‐ve bacteria (Escherichia coli, Neisseria gonorrhoeae, and Pseudomonas aeruginosa), and two fungi (Candida albicans and Aspergillus flavus). Aminothiazole (ester)‐functionalized PVC exhibited significant antimicrobial efficiencies against the investigated pathogens. However, incorporation of AgNPs or CuNPs to the modified PVC enhanced their inhibitory effect against the microorganisms under investigation. J. VINYL ADDIT. TECHNOL., 25:E137–E146, 2019. © 2018 Society of Plastics Engineers
Optical and structural properties of polyvinyl alcohol loaded with different concentrations of lignosulfonate
Authors: Nouh S. A. , Abou Elfadl A. , Benthami K. , Gupta Renu , Keshk Sherif M.A.S.
Published: October 2018

Polyvinyl alcohol/lignosulfonate (PVA/LS) composite films have been prepared using casting technique. The effect of lignosulfonate concentrations (0.001, 0.005, 0.01, 0.05, 0.1 and 0.5 wt %) on the optical and structural properties of polyvinyl alcohol (PVA) has been investigated using UV–vis spectroscopy and X‐ray diffraction. The results indicate that, the addition of LS led to a more compact structure of PVA, which resulted in an increase in its refractive index and amorphous phase. This was associated with a reduction in the optical energy gap that could be attributed to the increase in disorder structural of the composites. Moreover, the transmittance of PVA/LS composite film decreased with the increase of LS doping concentrations onto the PVA matrix. The results reflect the proper dispersion of LS in the PVA matrix that causes a strong intermolecular interaction between LS and PVA suggesting strong hydrogen bond formation between the hydroxyl group in PVA chains and the outer site groups of LS. Further, the transmission of the samples in the wavelength range of 370–780 nm, as well as any color changes, was studied. The color intensity ΔE, which is the color difference between the pure PVA sample and those with different LS concentration, increases with increasing the LS content and was accompanied by an increase in the yellow and red color components. J. VINYL ADDIT. TECHNOL., 25:85–90, 2019. © 2018 Society of Plastics Engineers
The influence of two‐stage variable temperature suspension polymerization on polyvinyl chloride resin: The molecular chain segment structure and thermal stability
Authors: Geng Yongfa , Yu Erlei , Wang Heyun , Zhao Weigang , Guo Rui , Wei Zhong
Published: October 2018

The suspension polymerization of polyvinyl chloride (PVC) was carried out at two different constant temperature conditions (52.5°C and 57.5°C) and at two‐stage variable temperature conditions (52.5–57.5°C). The molecular weight and molecular weight distribution were characterized by gel permeation chromatography (GPC). The unstable chlorine content, total double bond content, and conjugated diene content were explored via phenol substitution, catalytic bromine addition, and ultraviolet–visible spectroscopy (UV–Vis). pH meter and thermogravimetric analyzer (TGA) were used for the determination of the thermal stability. According to the results, due to the gradual consumption of the impurities and the effect of the local high temperature in the early stage of polymerization, which caused more molecular chain‐transfer and more structural defects, a large number of oligomers generated. A rapid increase in the molecular weight could be found until the conversion was close to 23%. A lower temperature should be conducive to reducing the structural defects in molecular segments. Based on these observations, we applied two‐stage variable temperature polymerization and compared the PVC resin at a similar molecular weight at a constant temperature of 56°C. The PVC resin produced by the two‐stage variable temperature polymerization process obtained a similar Polydispersity index (PDI), reduced the unstable chlorine content by 15.11%, reduced the total double bond structure content by 8.81%, reduced the conjugated diene structure content by 13.86%, and increased the thermal stability time by 13.91%, thereby improving the thermal stability of the PVC resin. J. VINYL ADDIT. TECHNOL., 25:E80–E87, 2019. © 2018 Society of Plastics Engineers
The asymptotic analysis of a junction of two elastic beams
Authors: Leugering G. , Nazarov S. A. , Slutskij A. S.
Published: October 2018

This paper is devoted to describing the asymptotic behavior of a structure consisting of thin elastic planar beams coupled at flexible joints. As the thickness of the beams tends to zero, we establish classical 1‐D beam equations for each individual structural element and transmission conditions across the joints.
Delusions and Prediction Error
Authors: Corlett Philip
Published: October 2018

Different empirical and theoretical traditions approach delusions differently. This chapter is about how cognitive neuroscience – the practice of studying the brain to draw conclusions about the mind – has been applied to the problem of belief and delusion. In particular, the focus is on a particular bridging theory, that of predictive coding. This theory holds that the brain contains a model of the world (and the self as an agent in that world). It uses that model to make predictions in order to adapt to the environment. Errors in those predictions can garner belief updating or be ignored, depending on how each prediction error response sustains adaptive fitness. The discussion will cover how delusions might arise and be maintained under the influence of aberrant prediction errors and what psychological and neural mechanisms of prediction error processing pertain to delusions, comparing and contrasting the theory with other prominent theories of delusions. The conclusion is that the single factor, prediction error account gives a parsimonious account of delusions that generates novel predictions about how best to treat delusions and incorporates numerous biological, clinical and phenomenological data regarding delusions.
Heterotic and bosonic string amplitudes via field theory
Authors: Azevedo Thales , Chiodaroli Marco , Johansson Henrik , Schlotterer Oliver
Published: October 2018

Abstract

Previous work has shown that massless tree amplitudes of the type I and IIA/B superstrings can be dramatically simplified by expressing them as double copies between field-theory amplitudes and scalar disk/sphere integrals, the latter containing all the α′-corrections. In this work, we pinpoint similar double-copy constructions for the heterotic and bosonic string theories using an α

′
-dependent field theory and the same disk/sphere integrals. Surprisingly, this field theory, built out of dimension-six operators such as (D

μ

F

μν
)2, has previously appeared in the double-copy construction of conformal supergravity. We elaborate on the α

′
→ ∞ limit in this picture and derive new amplitude relations for various gauge-gravity theories from those of the heterotic string.
The bearable compositeness of leptons
Authors: Frigerio Michele , Nardecchia Marco , Serra Javi , Vecchi Luca
Published: October 2018

Abstract

Partial compositeness as a theory of flavor in the lepton sector is assessed. We begin presenting the first systematic analysis of neutrino mass generation in this context, and identifying the distinctive mass textures. We then update the bounds from charged lepton flavor and CP violating observables. We put forward a U(1)3 × CP symmetry of the composite sector, in order to allow the new physics to be not far above the TeV scale. This hypothesis effectively suppresses the new contributions to the electron EDM and μ → eγ, by far the most constraining observables, and results in a novel pattern of flavor violation and neutrino masses. The CP violation in the elementary-composite mixing is shown to induce a CKM phase of the correct size, as well as order-one phases in the PMNS matrix. We compare with the alternative possibility of introducing multiple scales of compositeness for leptons, that also allow to evade flavor and CP constraints. Finally, we examine violations of lepton flavor universality in B-meson semi-leptonic decays. The neutral-current anomalies can be accommodated, predicting strong correlations among different lepton flavors, with a few channels close to the experimental sensitivity.
Towards a dual spin network basis for (3+1)d lattice gauge theories and topological phases
Authors: Delcamp Clement , Dittrich Bianca
Published: October 2018

Abstract

Using a recent strategy to encode the space of flat connections on a three-manifold with string-like defects into the space of flat connections on a so-called 2d Heegaard surface, we propose a novel way to define gauge invariant bases for (3+1)d lattice gauge theories and gauge models of topological phases. In particular, this method reconstructs the spin network basis and yields a novel dual spin network basis. While the spin network basis allows to interpret states in terms of electric excitations, on top of a vacuum sharply peaked on a vanishing electric field, the dual spin network basis describes magnetic (or curvature) excitations, on top of a vacuum sharply peaked on a vanishing magnetic field (or flat connection). This technique is also applicable for manifolds with boundaries. We distinguish in particular a dual pair of boundary conditions, namely of electric type and of magnetic type. This can be used to consider a generalization of Ocneanu’s tube algebra in order to reveal the algebraic structure of the excitations associated with certain 3d manifolds.
Kerr-Schild double field theory and classical double copy
Authors: Lee Kanghoon
Published: October 2018

Abstract

The Kerr-Schild (KS) formalism is a powerful tool for constructing exact solutions in general relativity. In this paper, we present a generalization of the conventional KS formalism to double field theory (DFT) and supergravities. We introduce a generalized KS ansatz for the generalized metric in terms of a pair of null vectors. Applying this ansatz to the equations of motion of DFT, we construct the generalized KS field equation. While the generalized KS equations are quadratic in the fields, we show that it is possible to find solutions by considering linear equations only. Furthermore, we construct a Killing spinor equation under the generalized KS ansatz. Based on this formalism, we show that the classical double copy structure, which represents solutions of the Einstein equation in terms of solutions of the Maxwell equation, can be extended to the entire massless string NS-NS sector. We propose a supersymmetric classical double copy which shows that solutions of the Killing spinor equation can be realized in terms of solutions of the BPS equation of the supersymmetric Maxwell theory.
Revisiting B → ππℓν at large dipion masses
Authors: Feldmann Thorsten , van Dyk Danny , Vos K. Keri
Published: October 2018

Abstract

We revisit QCD factorization of B → ππ form factors at large dipion masses, by deriving new constraints based on the analyticity properties of these objects. We then propose a parametrization of the form factors, inspired by the leading-twist QCD factorization formula, that incorporates all known analytic properties. This parameterization is used to interpolate between the QCDF results and the constraints from the B
* pole. Based on this interpolation, we predict the B → ππℓν decay rate in a larger phase space region than previous studies could. We obtain a partially-integrated branching ratio up to

$$ \mathrm{\mathcal{B}}\simeq \mathcal{O}\left({10}^{-6}\right) $$

ℬ
≃
O

10

−
6

, which implies that a measurement of the non-resonant semileptonic decay is potentially within reach of the Belle II experiment.
Structural basis of the nonribosomal codes for nonproteinogenic amino acid selective adenylation enzymes in the biosynthesis of natural products
Authors: Kudo Fumitaka , Miyanaga Akimasa , Eguchi Tadashi
Published: October 2018

Nonproteinogenic amino acids are the unique building blocks of nonribosomal peptides (NRPs) and hybrid nonribosomal peptide–polyketides (NRP–PKs) and contribute to their diversity of chemical structures and biological activities. In the biosynthesis of NRPs and NRP–PKs, adenylation enzymes select and activate an amino acid substrate as an aminoacyl adenylate, which reacts with the thiol of the holo form of the carrier protein to afford an aminoacyl thioester as the electrophile for the condensation reaction. Therefore, the substrate specificity of adenylation enzymes is a key determinant of the structure of NRPs and NRP–PKs. Here, we focus on nonproteinogenic amino acid selective adenylation enzymes, because understanding their unique selection mechanisms will lead to accurate functional predictions and protein engineering toward the rational biosynthesis of designed molecules containing amino acids. Based on recent progress in the structural analysis of adenylation enzymes, we discuss the nonribosomal codes of nonproteinogenic amino acid selective adenylation enzymes.
Best Practices in North American Pre-Clinical Medical Education in Sexual History Taking: Consensus From the Summits in Medical Education in Sexual Health
Authors: Rubin Elizabeth S. , Rullo Jordan , Tsai Perry , Criniti Shannon , Elders Joycelyn , Thielen Jacqueline M. , Parish Sharon J.
Published: October 2018

Introduction

This article discusses a blueprint for a sexual health communication curriculum to facilitate undergraduate medical student acquisition of sexual history taking skills and includes recommendations for important elements of a thorough sexual history script for undergraduate medical students.

Aim

To outline the fundamentals, objectives, content, timing, and teaching methods of a gold standard curriculum in sexual health communication.

Methods

Consensus expert opinion was documented at the 2012, 2014, and 2016 Summits in Medical Education in Sexual Health. Additionally, the existing literature was reviewed regarding undergraduate medical education in sexual health.

Main Outcome Measures

This article reports expert opinion and a review of the literature on the development of a sexual history taking curriculum.

Results

First-year curricula should be focused on acquiring satisfactory basic sexual history taking skills, including both assessment of sexual risk via the 5 Ps (partners, practices, protection from sexually transmitted infections, past history of sexually transmitted infections, and prevention of pregnancy) as well as assessment of sexual wellness—described here as a sixth P (plus), which encompasses the assessment of trauma, violence, sexual satisfaction, sexual health concerns/problems, and support for gender identity and sexual orientation. Second-year curricula should be focused on incorporating improved clinical reasoning, emphasizing sexual history taking for diverse populations and practices, and including the impact of illness on sexual health. Teaching methods must include varied formats. Evaluation may be best as a formative objective structured clinical examination in the first year and summative in the second year. Barriers for curriculum development may be reduced by identifying faculty champions of sexual health/medicine.

Clinical Implications

Medical students will improve their skills in sexual history taking, which will ultimately impact patient satisfaction and clinical outcomes. Future research is needed to validate this proposed curriculum and assess the impact on clinical skills.

Strengths & Limitations

This article assimilates expert consensus and existing clinical guidelines to provide a novel structured approach to curriculum development in sexual health interviewing in the pre-clinical years.

Conclusion

The blueprint for developing sexual history taking skills includes a spiral curriculum with varied teaching formats, incorporation of a sexual history script that incorporates inquiry about sexual wellness, and longitudinal assessment across the pre-clinical years. Ideally, sexual health communication content should be incorporated into existing clinical interviewing and physical examination courses.
Racial and ethnic differences in trends in dementia prevalence and risk factors in the United States
Authors: Chen Cynthia , Zissimopoulos Julie M.
Published: October 2018

Introduction

Disparities in dementia prevalence across racial/ethnic groups in the United States may not be narrowing over time.

Methods

Data from Health and Retirement Study (2000 to 2012) were analyzed. Dementia was ascertained based on cognitive, functional measures. Logistic regression was used to quantify association between dementia and risk factors, including chronic conditions, use of drug treatment for them, separately for whites, blacks, and Hispanics.

Results

Disparities in dementia prevalence declined between blacks and whites and increased between Hispanics and whites. Adjusting for risk factors reduced but did not eliminate disparities. Compared to no hypertension, untreated hypertension was associated with increased risk of dementia for all racial/ethnic groups while treated hypertension was associated with reduced risk for whites. Diabetes treated with oral drugs was not associated with increased dementia risk.

Discussion

Racial disparities in dementia may be reduced by prevention and management of disease and promoting educational attainment among blacks and Hispanics.
Apostle Islands National Lakeshore: A Review of Search and Rescue and Emergency Medical Services Operations, 2006–2015
Authors: Small Elan R. , Burbank Sarah R. , Lorme Jeanette M. , Carlson Karl , Erickson Timothy B. , Young David S.
Published: October 2018

Introduction

Apostle Islands National Lakeshore (APIS) lies at the northern tip of Wisconsin and is home to a network of 21 islands along Lake Superior. The goal of this report is to investigate search and rescue (SAR) and emergency medical services (EMS) trends at APIS in an effort to improve visitor safety and resource allocation.

Methods

This study is a retrospective analysis reviewing APIS SAR reports and annual EMS summary reports from January 1, 2006, to December 31, 2015. Information related to incident type, incident date, individual demographic characteristics and activities, injury/illness type, cost, and contributing factors were recorded and analyzed in frequency tables.

Results

From 2006 to 2015, APIS SAR conducted 133 total missions assisting 261 individuals—200 not injured/ill, 57 injured/ill, and 4 fatalities. Median cost per SAR incident involving aircraft totaled $21,695 (range: $2,993–141,849), whereas incidents not involving aircraft had a median cost of $363 (range: $35–8,830). Nonmotorized boating was the most common activity resulting in SAR incidents. All 4 fatalities were attributed to drowning while kayaking or swimming. Cold-related injury/illness accounted for nearly half of all injuries/illnesses (45%) with the most commonly reported contributing factor being high winds. EMS responded to a total of 134 incidents. Trauma and first aid accounted for 43% and 34% of EMS workload, respectively.

Conclusions

Overall, this study highlights the hazards associated with the frigid and rough conditions of Lake Superior. The reported results aim to help APIS personnel more saliently convey risks to visitors and plan appropriately in an effort to decrease the need for future rescues.
Laser processes set to give piston rings for LBE engines unprecedented wear resistance
Authors: Atkinson Simon
Published: October 2018

Federal-Mogul Powertrain, part of Federal-Mogul LLC that designs and manufactures original equipment power-train components and systems protection products for automotive, heavy-duty, industrial and transportation applications, has developed what it describes as an innovative coating process that could enable large-bore two-stroke and four-stroke engines to meet the challenges of increasing loads and temperatures. This brief article takes a look at the technology.
Scattering of internal tides by barotropic quasigeostrophic flows
Authors: Savva Miles A. C. , Vanneste Jacques
Published: October 2018

Oceanic internal tides and other inertia–gravity waves propagate in an energetic turbulent flow whose length scales are similar to the wavelengths. Advection and refraction by this flow cause the scattering of the waves, redistributing their energy in wavevector space. As a result, initially plane waves radiated from a source such as a topographic ridge become spatially incoherent away from the source. To examine this process, we derive a kinetic equation which describes the statistics of the scattering under the assumptions that the flow is quasigeostrophic, barotropic and well represented by a stationary homogeneous random field. Energy transfers are quantified by computing a scattering cross-section and shown to be restricted to waves with the same frequency and identical vertical structure, hence the same horizontal wavelength. For isotropic flows, scattering leads to an isotropic wave field. We estimate the characteristic time and length scales of this isotropisation, and study their dependence on parameters including the energy spectrum of the flow. Simulations of internal tides generated by a planar wavemaker carried out for the linearised shallow-water model confirm the pertinence of these scales. A comparison with the numerical solution of the kinetic equation demonstrates the validity of the latter and illustrates how the interplay between wave scattering and transport shapes the wave statistics.
ESTIMATING THE HEALTH AND SOCIOECONOMIC EFFECTS OF COUSIN MARRIAGE IN SOUTH ASIA
Authors: Mobarak A. Mushfiq , Chaudhry Theresa , Brown Julia , Zelenska Tetyana , Khan M. Nizam , Chaudry Shamyla , Wajid Rana Abdul , Bittles Alan H. , Li Steven
Published: October 2018

The effects of marriage between biological relatives on the incidence of childhood genetic illness and mortality are of major policy significance, as rates of consanguinity exceed 50% in various countries. Empirical research on this question is complicated by the fact that consanguinity is often correlated with poverty and other unobserved characteristics of households, which may have independent effects on mortality. This study has developed an instrumental variables empirical strategy to re-examine this question, based on the concept that the availability of unmarried cousins of the opposite gender at the time of marriage creates quasi-random variation in the propensity to marry consanguineously. Using primary data collected in Bangladesh in 2006–07 and Pakistan in 2009–10, the study found that previous estimates of the impact of consanguinity on child health were biased and falsely precise. The study also empirically investigated the social and economic causes of consanguinity (including marital quality) and concludes that marrying a cousin can have positive economic effects for one’s natal family, by allowing deferral of dowry payments until after marriage.
Reclaiming Responsibility: The Case of Welfare-to-Work Policy
Authors: ERIKSEN ANDREAS
Published: October 2018

Welfare-to-work programmes have a contested normative foundation. Critics argue that ‘citizen responsibility’ is being promoted to the sacrifice of more important social values, such as solidarity and fairness. This paper seeks to recapture what is valuable in citizen responsibility and to challenge the idea that the concept is intrinsically bound up with detrimental policy strategies. The paper develops a view of the responsible citizen as an appropriate addressee of moral expectations. This view highlights how addressing someone as responsible involves a presumption of reasonableness. Thereafter, the view is applied to conditions of street-level interaction, the design of policy instruments, and political discourse.