bluuebunny/crossref_metadata_2025 huggingface dataset:
Algal scavenging of mercury in preindustrial Arctic lakes
Authors: Outridge P. M. , Stern G. A. , Hamilton P. B. , Sanei H.
Published: February 2019

The geochemical speciation of total mercury (THg) was examined in pre‐1800 Arctic lake sediments to improve understanding of the factors controlling “natural baseline” THg. Solid‐phase binding forms of THg were determined by sequential extraction of dated cores from three lakes in different ecozones (barren tundra, grassy tundra, and boreal forest). Sediment organic matter (OM) was mostly of algal origin. Mercury was highly concentrated in the sediment OM fraction (OM‐Hg), comprising 60–87% of THg, while OM (as total organic carbon) constituted only 0.6–13% of sediment dry weight (DW). OM‐Hg concentrations were equivalent to 159 ± 13 to 776 ± 215 ng Hg g−1 DW in algal OM and were enriched 2–39 times compared to sediment THg, indicating that even small changes in algal OM inputs could significantly alter THg. OM‐Hg explained 76–96% of the variation in THg concentrations over many centuries. Concentrations of S2 carbon (an algal productivity proxy) and OM‐Hg were significantly correlated in two lakes but not in the boreal forest lake possibly because of OM remineralization in its deep water column. Fluxes of S2 carbon, OM‐Hg, and THg were highly correlated in the barren tundra lake but could not be calculated for the other lakes. The results overall indicate that high algal Hg concentrations due to scavenging of available Hg controlled OM‐Hg flux to sediments, thus driving changes in THg concentrations and fluxes. These findings improve our understanding of the long‐term stability of baseline THg in northern lakes under a changing climate, including in the modern era.
Intraspecific variation in a dominant prey species can bias marine predator dietary estimates derived from stable isotope analysis
Authors: Polito Michael J. , Trivelpiece Wayne Z. , Reiss Christian S. , Trivelpiece Susan G. , Hinke Jefferson T. , Patterson William P. , Emslie Steven D.
Published: February 2019

It is often assumed that variation in consumer stable isotope values (δ15N and δ13C) reflect shifts in diet between isotopically distinct prey species. However, an alternate hypothesis is that such variation could be as a result of spatial, temporal, or ontogenetic variation in the stable isotope values of a key prey species that propagate up marine food chains. In the Southern Ocean, Antarctic krill (Euphausia superba) occupy a key position, linking primary production to secondary consumers including fish, squid, seabirds, and marine mammals. As such Antarctic krill represent an ideal prey species to test the critical assumptions behind what has become a common method of dietary analysis in marine predators. Similar to previous studies, we found that stable isotope values of Antarctic krill exhibit significant intraspecific variation associated with both ontogenetic (size) and oceanographic factors (chlorophyll a concentration). Our modeling results showed that intraspecific variation in the stable isotope values of Antarctic krill has the potential to force mean isotope values of krill predators by as much as 2.4‰, independent of changes in the species composition of diet. Our findings indicate that intraspecific variation in the stable isotope values of a single, dominate prey species, such as Antarctic krill, has the potential to bias both absolute and relative estimates of marine predator diets using stable isotope mixing models. Therefore, caution is warranted to avoid spatial, temporal, and ontogenetic mismatches between the stable isotope values of prey sources used in mixing models and the actual stable isotope values of prey consumed by marine predators.
Randomized, double‐blind, phase III clinical study of a novel nanotechnological topical anesthetic formulation containing lidocaine 25 mg/g and prilocaine 25 mg/g (nanorap) in skin phototypes I–III patients with ablative fractional CO2 laser treatment indication in the forehead
Authors: Gobbato Cíntia , Gobbato André , Magalhães Tainah B. , Mendes Gustavo D. , Ilha Jaime O. , Moreno Ronilson A. , Antunes Natalícia J. , De Nucci Gilberto
Published: February 2019

Background and Objectives

Nanotechnology may increase the speed of penetration into the skin. This study evaluated the efficacy, safety, and pharmacokinetics of a novel topical anesthetic nanocapsule formulation (2 g) containing 2.5% lidocaine and 2.5% prilocaine (nanorap—test formulation) compared to placebo (control formulation) in skin types I–III patients of both sexes submitted to the ablative fractional CO2 laser treatment.

Methods

The patients (n = 120) included in this double‐blind, single‐center, randomized trial, received topical application of 2 g of the test formulation (50 mg lidocaine + 50 mg prilocaine) and placebo on the forehead region. Efficacy was assessed as pain sensation in four quadrants of each side of the forehead using a visual analogue scale immediately (0 min) and at 30, 60, and 90 minutes after laser application compared to placebo. The safety and tolerability of the test product were evaluated based on the occurrence of systemic adverse events as well as the occurrence of immediate and late skin reactions. Pharmacokinetic evaluation was performed in plasma of eight patients using a validated LC‐MS/MS method for drugs quantification.

Results

Nanorap induced a clinically significant reduction in the pain assessment at all evaluated times (57.2%, 41.6%, 38.6%, and 37.3% at 0, 30, 60, and 90 minutes after drug application, respectively. Mean values of Cmax were 14.20 and 5.36 ng/ml and tmax were 3.5 and 1.8 hour for lidocaine and prilocaine, respectively. No systemic adverse events were observed.

Conclusion

The nanorap formulation demonstrated a clinically and statistically significant efficacy providing analgesia after the ablative fractional CO2 laser therapy in the investigated patients, when compared to placebo. The product also presented good safety and tolerability. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
Near‐Infrared‐Induced Cationic Polymerization Initiated by Using Upconverting Nanoparticles and Titanocene
Authors: Li Zhiquan , Zhu Junzhe , Guan Xin , Liu Ren , Yagci Yusuf
Published: February 2019

A new near‐infrared (NIR)‐sensitized photoinitiating system for free‐radical‐promoted cationic polymerization of oxirane and vinyl monomers such as cyclohexene oxide, and n‐butyl vinyl ether (BVE), and N‐vinyl carbazole (NVC) is described. A three‐component photoinitiating system consists of upconverting nanoparticles (UCNPs), titanium‐complex free radical photoinitiator (Irgacure 784, titanocene), and diphenyl iodonium hexafluorophosphate (Ph2I+PF6
−). Upon NIR laser irradiation at 980 nm, the radicals generated from titanocene by the visible light emitted by UCNP abstract hydrogen or add to the monomer, forming electron donor radicals that can be oxidized by iodonium salt to initiate cationic polymerization.
Reproducibility of Dietary Biomarkers in a Multiethnic Asian Population
Authors: Whitton Clare , Neelakantan Nithya , Ong Choon Nam , van Dam Rob M.
Published: February 2019

Scope

Dietary biomarkers allow for study of diet and disease risk relationships, but a key requirement is that these biomarkers are reproducible and reflect long‐term diet. This study assesses reproducibility of selected dietary biomarkers in a multi‐ethnic Asian population, and quantifies diet‐disease relationship attenuation arising from use of a single biomarker measurement.

Methods and results

Intra‐class correlation coefficients (ICC) are used to evaluate the reproducibility of urinary isoflavone and enterolignan, total plasma fatty acid (FA), and serum carotenoid concentrations measured 4 months apart in adult Singapore residents (ethnic Chinese, n 59; Malay, n 46; Indian, n 56). Total carotenoid ICC is 0.75 (95% confidence interval (CI) 0.68, 0.81), ranging from 0.63 to 0.84 for individual carotenoids. FA ICC (median) is 0.74 (inter‐quartile range 0.70–0.78). Total isoflavone ICC (95% CI) is 0.21 (0.06–0.35). Total enterolignan ICC is 0.42 (0.28, 0.54). Attenuation factors associated with a single time point measure ranged from 0.74 to 0.94 for carotenoids and FAs, and 0.42 to 0.70 for isoflavones and enterolignans.

Conclusions

In a multi‐ethnic Asian population, single measures of most serum carotenoids and plasma FAs likely represent habitual diet, whereas reproducibility of urinary isoflavones and enterolignans is moderate, possibly due to rapid excretion.
Biophysical model‐based parameters to classify tumor recurrence from radiation‐induced necrosis for brain metastases
Authors: Narasimhan Saramati , Johnson Haley B. , Nickles Tanner M. , Miga Michael I. , Rana Nitesh , Attia Albert , Weis Jared A.
Published: February 2019

Purpose

Stereotactic radiosurgery (SRS) is used for local control treatment of patients with intracranial metastases. As a result of SRS, some patients develop radiation‐induced necrosis. Radiographically, radiation‐induced necrosis can appear similar to tumor recurrence in magnetic resonance (MR) T1‐weighted contrast‐enhanced imaging, T2‐weighted MR imaging, and Fluid‐Attenuated Inversion Recovery (FLAIR) MR imaging. Radiographic ambiguities often necessitate invasive brain biopsies to determine lesion etiology or cause delayed subsequent therapy initiation. We use a biomechanically coupled tumor growth model to estimate patient‐specific model parameters and model‐derived measures to noninvasively classify etiology of enhancing lesions in this patient population.

Methods

In this initial, preliminary retrospective study, we evaluated five patients with tumor recurrence and five with radiation‐induced necrosis. Longitudinal patient‐specific MR imaging data were used in conjunction with the model to parameterize tumor cell proliferation rate and tumor cell diffusion coefficient, and Dice correlation coefficients were used to quantify degree of correlation between model‐estimated mechanical stress fields and edema visualized from MR imaging.

Results

Results found four statistically relevant parameters which can differentiate tumor recurrence and radiation‐induced necrosis.

Conclusions

This preliminary investigation suggests potential of this framework to noninvasively determine the etiology of enhancing lesions in patients who previously underwent SRS for intracranial metastases.
Prognostic factors for response to treatment by corticosteroid injection or surgery in carpal tunnel syndrome (palms study): A prospective multicenter cohort study
Authors: Jerosch‐Herold Christina , Shepstone Lee , Houghton Julie , Wilson Edward C. F. , Blake Julian
Published: February 2019

Introduction

Studies of prognosis for surgery and corticosteroid injection for carpal tunnel syndrome (CTS) have considered only a limited range of explanatory variables for outcome.

Methods

Data were prospectively collected on patient‐reported symptoms, physical and psychological functioning, comorbidity, and quality of life at baseline and every 6 months for up to 2 years. Outcomes were patient‐rated change over a 6‐month period and symptom‐severity score at 18 months.

Results

In total, 754 patients with CTS completed baseline questionnaires, and 626 (83%) completed follow‐up to 18 months. Multivariable modeling identified, independent of symptom severity at outset, higher health utility, fewer comorbidities, and lower anxiety as significant predictors of better outcome from surgery. In patients treated by steroid injection, independent of symptom severity at outset, shorter duration of symptoms and having no prior injection were significant predictors of better outcome.

Discussion

These multivariable models of outcome may inform shared decision making about treatment for CTS. Muscle Nerve, 2019
Functional electrical stimulation following nerve injury in a large animal model
Authors: Cercone Marta , Jarvis Jonathan C. , Ducharme Norm G. , Perkins Justin , Piercy Richard J. , Willand Michael P. , Mitchell Lisa M. , Sledziona Michael , Soderholm Leo , Cheetham Jonathan
Published: February 2019

Introduction: Controversy exists over the effects of functional electrical stimulation (FES) on reinnervation. We hypothesized that intramuscular FES would not delay reinnervation after recurrent laryngeal nerve (RLn) axonotmesis.Methods: RLn cryo‐injury and electrode implantation in ipsilateralposterior cricoarytenoidmuscle (PCA) were performed in horses. PCA was stimulated for 20 weeks in eight animals; seven served as controls. Reinnervation was monitored through muscle response to hypercapnia, electrical stimulation and exercise. Ultimately, muscle fiber type proportions and minimum fiber diameters, and RLn axon number and degree of myelination were determined.Results: Laryngeal function returned to normal in both groups within 22 weeks. FES improved muscle strength and geometry, and induced increased type I:II fiber proportion (p = 0.038) in the stimulated PCA. FES showed no deleterious effects on reinnervation.Discussion: Intramuscular electrical stimulation did not delay PCA reinnervation after axonotmesis. FES can represent a supportive treatment to promote laryngeal functional recovery after RLn injury.Muscle Nerve59:717–725, 2019
Multiphase topology optimization with a single variable using the phase‐field design method
Authors: Seong Hong Kyoung , Kim Cheol Woong , Yoo Jeonghoon , Lee Jaewook
Published: February 2019

In this study, a multimaterial topology optimization method using a single variable is proposed by combining the solid isotropic material with penalization method and the reaction‐diffusion equation. Unlike ordinary multimaterial optimization, which requires several variables depending on the number of material types, this method intends to represent various materials as one variable. The proposed method combines two special functions in the sensitivity analysis of the objective function to converge the design variable into prespecified density values defined for each of the multimaterials. The composition constraint based on a normal distribution function is also introduced to estimate the distribution of each target density value in a single variable. It enables density exchange between multiple materials by increasing or decreasing the amount of a specific material. The proposed method is applied to structural and electromagnetic problems to verify its effectiveness, and its usefulness is also confirmed from the viewpoint of cost and computation time.
Synthesis of Non‐Symmetrical Nitrogen‐Containing Curcuminoids in the Pursuit of New Anticancer Candidates
Authors: Theppawong Atiruj , Van de Walle Tim , Grootaert Charlotte , Van Hecke Kristof , Catry Nathalie , Desmet Tom , Van Camp John , D'hooghe Matthias
Published: February 2019

Curcumin is known to display pronounced anticancer effects and a variety of other biological activities. However, the low bioavailability and fast metabolism of this molecule present an issue of concern with respect to its medicinal applications. To address this issue, structural modifications of the curcumin scaffold can be envisioned as a strategy to improve both the solubility and stability of this chemical entity, without compromising its biological activities. Previous work in our group targeted the synthesis of symmetrical azaheteroaromatic curcuminoids, which showed better solubility and cytotoxicity profiles compared to curcumin. In continuation of that work, we now focused on the synthesis of non‐symmetrical nitrogen‐containing curcuminoids bearing both a phenolic and an azaheteroaromatic moiety. In that way, we aimed to combine good solubility, antioxidant potential and cytotoxic properties into one molecule. Some derivatives were selected for further chemical modification of their rather labile β‐diketone scaffold to the corresponding pyrazole moiety. In this way, thirteen new non‐symmetrical aza‐aromatic curcuminoids and four pyrazole‐based analogues were successfully synthesized in a yield of 11–69 %. All newly synthesized analogues were evaluated for their antioxidant properties, reactive oxygen species (ROS) production, water solubility and anticancer activities. Several novel derivatives displayed good cytotoxicity profiles compared to curcumin, in combination with an improved water solubility and stability, and were thus identified as potential hit scaffolds for further optimization studies.
Prevalence of anxiety, depression, and posttraumatic stress disorder in parents of children with cancer: A meta‐analysis
Authors: van Warmerdam Jacqui , Zabih Veda , Kurdyak Paul , Sutradhar Rinku , Nathan Paul C. , Gupta Sumit
Published: February 2019

Background

For parents, a diagnosis of cancer in their child is a traumatic experience. However, there is conflicting evidence about the risk of developing mental illness among parents following diagnosis. Our objective was to conduct a meta‐analysis to determine the prevalence of mental illness in parents of children with cancer.

Methods

Four databases were searched to identify articles describing the prevalence of anxiety, depression, or posttraumatic stress disorder (PTSD) in parents of pediatric cancer patients. Two reviewers independently screened and extracted data. Subgroup analyses by gender and phase of cancer experience were selected a priori. Studies were reviewed in accordance with PRISMA guidelines.

Results

Of 11 394 articles identified, 58 met inclusion criteria. Reported prevalence was highly heterogeneous, ranging from 5% to 65% for anxiety (pooled prevalence 21% [95% CI, 13%–35%]), 7% to 91% for depression (pooled prevalence 28% [95% CI, 23%–35%]), and 4% to 75% for PTSD (pooled prevalence 26% [95% CI, 22%–32%]). Prevalence was consistently higher than noncancer parental controls. Heterogeneity was not explained by parental gender or child's cancer phase and was instead likely due to significant methodological differences in measurement tools and defined thresholds.

Conclusions

Parents of children with cancer have a higher prevalence of anxiety, depression, and PTSD compared with population controls. Yet, the reported prevalence of mental illness was highly variable, hampering any conclusive findings on absolute prevalence. To better understand the risk of long‐term mental illness in this population and target interventions, future studies must adhere to standardized reporting and methods.
Sleep, emotional distress, and physical health in survivors of childhood cancer: A report from the Childhood Cancer Survivor Study
Authors: Daniel Lauren C. , Wang Mingjuan , Mulrooney Daniel A. , Srivastava Deo Kumar , Schwartz Lisa A. , Edelstein Kim , Brinkman Tara M. , Zhou Eric S. , Howell Rebecca M. , Gibson Todd M. , Leisenring Wendy , Oeffinger Kevin C. , Neglia Joseph , Robison Leslie L. , Armstrong Gregory T. , Krull Kevin R.
Published: February 2019

Objective

Sleep disorders are associated with psychological and physical health, although reports in long‐term survivors of childhood cancer are limited. We characterized the prevalence and risk factors for behaviors consistent with sleep disorders in survivors and examined longitudinal associations with emotional distress and physical health outcomes.

Methods

Survivors (n = 1933; median [IQR] age = 35 [30, 41]) and siblings (n = 380; age = 33 [27, 40]) from the Childhood Cancer Survivor Study completed measures of sleep quality, fatigue, and sleepiness. Emotional distress and physical health outcomes were assessed approximately 5 years before and after the sleep survey. Multivariable logistic or modified Poisson regression models examined associations with cancer diagnosis, treatment exposures, and emotional and physical health outcomes.

Results

Survivors were more likely to report poor sleep efficiency (30.8% vs 24.7%; prevalence ratio [PR] = 1.26; 95% confidence interval, 1.04‐1.53), daytime sleepiness (18.7% vs 14.2%; PR = 1.31 [1.01‐1.71]), and sleep supplement use (13.5% vs 8.3%; PR = 1.56 [1.09‐2.22]) than siblings. Survivors who developed emotional distress were more likely to report poor sleep efficiency (PR = 1.70 [1.40‐2.07]), restricted sleep time (PR = 1.35 [1.12‐1.62]), fatigue (PR = 2.11 [1.92‐2.32]), daytime sleepiness (PR = 2.19 [1.71‐2.82]), snoring (PR = 1.85 [1.08‐3.16]), and more sleep medication (PR = 2.86 [2.00‐4.09]) and supplement use (PR = 1.89[1.33‐2.69]). Survivors reporting symptoms of insomnia (PR = 1.46 [1.02‐2.08]), fatigue (PR = 1.31 [1.01‐1.72]), and using sleep medications (PR = 2.16 [1.13‐4.12]) were more likely to develop migraines/headaches.

Conclusions

Survivors report more sleep difficulties and efforts to manage sleep than siblings. These sleep behaviors are related to worsening or persistently elevated emotional distress and may result in increased risk for migraines. Behavioral interventions targeting sleep may be important for improving health outcomes.
Systematic review on women's values and preferences concerning breast cancer screening and diagnostic services
Authors: Mathioudakis Alexander G. , Salakari Minna , Pylkkanen Liisa , Saz‐Parkinson Zuleika , Bramesfeld Anke , Deandrea Silvia , Lerda Donata , Neamtiu Luciana , Pardo‐Hernandez Hector , Solà Ivan , Alonso‐Coello Pablo
Published: February 2019

Background

There is still lack of consensus on the benefit‐harm balance of breast cancer screening. In this scenario, women's values and preferences are crucial for developing health‐related recommendations. In the context of the European Commission Initiative on Breast Cancer, we conducted a systematic review to inform the European Breast Guidelines.

Methods

We searched Medline and included primary studies assessing women's values and preferences regarding breast cancer screening and diagnosis decision making. We used a thematic approach to synthesise relevant data. The quality of evidence was determined with GRADE, including GRADE CERQual for qualitative research.

Results

We included 22 individual studies. Women were willing to accept the psychological and physical burden of breast cancer screening and a significant risk of overdiagnosis and false‐positive mammography findings, in return for the benefit of earlier diagnosis. The anxiety engendered by the delay in getting results of diagnostic tests was highlighted as a significant burden, emphasising the need for rapid and efficient screening services, and clear and efficient communication. The confidence in the findings was low to moderate for screening and moderate for diagnosis, predominantly because of methodological limitations, lack of adequate understanding of the outcomes by participants, and indirectness.

Conclusions

Women value more the possibility of an earlier diagnosis over the risks of a false‐positive result or overdiagnosis. Concerns remain that women may not understand the concept of overdiagnosis. Women highly value time efficient screening processes and rapid result delivery and will accept some discomfort for the peace of mind screening may provide.
Highly Selective Optical Detection of Fe3+ Ions in Aqueous Solution Using Label‐Free Silicon Nanocrystals
Authors: Linehan Keith , Carolan Darragh , Doyle Hugh
Published: February 2019

High brightness amine‐terminated silicon nanocrystals (Si NCs) have been utilized in a simple and rapid assay for the highly selective and sensitive detection of Fe3+ via quenching of their strong blue luminescence, without the need for analyte‐specific labeling groups. Sensitive detection of Fe3+ is successfully demonstrated, with a linear relationship observed between luminescence quenching and Fe3+ concentration from 5 × 10−6 to 900 × 10−6m and a limit of detection of 1.3 × 10−6m. The Si NCs show excellent selectivity toward Fe3+ ions, with no quenching of the luminescence signal induced by the presence of Fe2+ ions, allowing for solution phase discrimination between the ionic species in different charge states.
SiOC‐Accelerated Graphene Grown on SiO2/Si with Tunable Electronic Properties
Authors: Garman Paul D. , Yang Hao , Yen Ying‐Chieh , Yu Jianfeng , Kwak Kwang Joo , Malkoc Veysi , Talesara Vishank V. , Lee Ly J. , Lu Wu
Published: February 2019

A facile method is developed for fast and high‐coverage graphene growth on silicon wafers with covalent bonding by using atmospheric pressure chemical vapor deposition (APCVD) with methane as the carbon source and high temperature silicone rubber as the silicon oxycarbide (SiOC) source. The SiOC transition layer can facilitate and accelerate the formation of graphene. The formation of graphene networks with strong covalent bonding provides a combination of unique properties including higher mechanical strength and lower friction coefficient than a silicon wafer, excellent electrical conductivity, and high carrier mobility up to 275 cm2 V−1 s−1.
[6]‐Gingerol enhances the cisplatin sensitivity of gastric cancer cells through inhibition of proliferation and invasion via PI3K/AKT signaling pathway
Authors: Luo Youjun , Zha Lin , Luo Lumeng , Chen Xue , Zhang Qi , Gao Caixia , Zhuang Xibing , Yuan Sujuan , Qiao Tiankui
Published: February 2019

Cisplatin‐based chemotherapy is a widely used chemotherapeutic regimen for gastric cancer; however, drug resistance limits its efficacy. [6]‐Gingerol has been found to exhibit anticancer effects. Here, we aim to explore the potential of [6]‐gingerol in combination with cisplatin as a new regimen for gastric cancer. CCK‐8 assay and colony formation assay were used to determine the effect of [6]‐gingerol in combination with cisplatin on cell viability of gastric cancer cells. Flow cytometry was performed to assess cell cycle distribution. Wound‐healing assay and transwell invasion assay were conducted to examine the migration and invasion abilities. Cell cycle and invasion‐related proteins and mRNAs, as well as PI3K/AKT signaling proteins, were assessed by western blotting and quantitative real‐time polymerase chain reaction. Combination of [6]‐gingerol with cisplatin inhibited cell viability and enhanced cell cycle arrest at G1 phase compared with cisplatin alone. The combination treatment inhibited cell migration and invasion ability and decreased cyclin D1, cyclin A2, matrix metalloproteinase‐9, p‐PI3K, AKT, and p‐AKT protein expressions and increased P21 and P27 mRNA levels. Our study demonstrates that [6]‐gingerol enhances the cisplatin sensitivity of gastric cancer cells and that the mechanisms involve G1 phase arrest, migration and invasion suppression via PI3K/AKT signaling pathway.
Synoptic‐flow interaction with valley cold‐air pools and effects on cold‐air pool persistence: Influence of valley size and atmospheric stability
Authors: Sheridan Peter F.
Published: February 2019

Idealized two‐dimensional simulations have been used to examine the dependence of valley cold‐air pool (CAP) behaviour, morphology and duration (persistence) on terrain scale. The simulations use terrain of constant aspect ratio but ranging from modest to Alpine scale, under midlatitude winter conditions with a finite background flow and incorporating a diurnal cycle. CAPs in smaller valleys are found to be more morphologically constrained, whereas larger valleys provide scope for more complex flow dynamics and more dramatic interplay of the external flow with the valley, including gravity wave breaking. Simulations of a valley within a plateau show that, as valley depth exceeds the depth‐scale of the nocturnal stable boundary layer, the CAP becomes increasingly confined and sheltered from the background flow (reduced mixing), becoming harder to remove by processes related to daytime insolation, and it can eventually become persistent (never removed). Both the surrounding terrain and gravity wave dynamics are found to play a part in the enhancement of sheltering. Therefore background atmospheric stability and wind are also crucial, summarized in a non‐dimensional valley depth parameter which largely determines CAP duration. More stable conditions, representative of (for instance) large‐scale subsidence or warm advection aloft, result in longer durations and a greater likelihood of persistence. Stronger nocturnal radiative cooling results in stronger CAPs, which are harder again to remove. Several mechanisms appear to act in concert to give rise to these behaviours and the dependence on non‐dimensional valley depth. Replacing the valley‐in‐plateau with a double hill enhances wave breaking, which complicates the relationship to non‐dimensional valley depth, reducing CAP duration significantly when subsidence or warm advection‐like effects are absent.
Investigation of physicochemical properties of CuSn‐based PAN nanofibers prepared via electrospinning method
Authors: Choi Jinhee , Park Juyun , Kang Jisoo , Frey Margaret W. , Oh Jin‐Woo , Kang Yong‐Cheol
Published: February 2019

Copper‐tin (CuSn) nanomaterials have been receiving substantial attention due to their excellent thermal, electrical, and optical properties. However, how such properties are affected based on heat treatment temperature and chemical composition of copper and tin is still not very well understood. In this paper, CuSn nanofibers were fabricated by electrospinning a precursor solution of polyacrylonitrile, copper, and tin. Calcination temperatures were selected using thermogravimetric/differential thermal analysis (TG/DTA) and Fourier transform infrared (FT‐IR) results. Analytical techniques such as scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), and ultraviolet photoelectron spectroscopy (UPS) were employed to investigate the physicochemical properties of the CuSn nanofibers. SEM images and EDS revealed the formation of pores on the nanofibers and high concentrations of tin were in the core, while copper was located on the surface. XRD results confirmed the monoclinic phase of Cu6Sn5 for the CuSn nanofibers because peaks for diffraction angles at 27.6°, 53.4°, and 60.0° were observed. XPS results showed that Cu―C and Sn―C bonds occur at binding energies around 932 and 484 eV, respectively. The work function of the CuSn NF heat treated at 150°C was calculated from the UPS spectra, and the value was 4.19 eV.
3D Hierarchical Nanorod@Nanobowl Array Photoanode with a Tunable Light‐Trapping Cutoff and Bottom‐Selective Field Enhancement for Efficient Solar Water Splitting
Authors: Tang Songtao , Li Mingyang , Huang Duan , Qiu Weitao , Xiao Shuang , Tong Yexiang , Yang Shihe
Published: February 2019

Constructing 3D nanophotonic structures is regarded as an effective means to realize both efficient light absorption and efficient charge separation. However, most of the 3D structures reported so far enhance light trapping beyond the absorption onset wavelength, and thus greatly attentuate or even completely block the long‐wavelength light, which could otherwise be efficiently absorbed by narrow‐bandgap materials in a Z‐scheme or tandem device. In addition, constructing a 3D conductive substrate often involves complex processes causing increased cost and upscaling problems. To overcome these shortcomings, a novel 3D hematite nanorod@nanobowl array nanophotonic structure is designed and fabricated by a low‐cost method. This unique structure can enhance light absorption with tunable cutoffs and rationally concentrate photons right above the bowl bottom, enabling efficient charge separation. By loading NiFeOx as a cocatalyst, a high photocurrent density of 3.41 ± 0.2 mA cm−2 at 1.23 V versus reversible hydrogen electrode (RHE) can be obtained, which is 2.35 times that with a planar structure in otherwise the same system.
Thermodynamic and Kinetic Analysis for Transformation of Oxide Inclusions in Solid 304 Stainless Steels
Authors: Wang Jujin , Li Weifu , Ren Ying , Zhang Lifeng
Published: February 2019

Inclusions in 304 stainless steels are transformed from manganese silicate to manganese chromite (spinel) upon heating in the range of 1000–1350 °C, while this transformation is not observed when heating temperature is 1400 °C. Thermodynamic analysis with software FactSage™ is applied in interpreting the transformation. Manganese chromite spinel, with light color under SEM, is deemed to be formed on the surface of MnO–SiO2 inclusions by the reaction between Cr in steel matrix and MnO–SiO2 in inclusions. Heating experiments with different time at 1235 °C (rolling insulation temperature) are carried out to confirm the kinetics of the transformation reaction. Mass transfer coefficients of inclusions’ composition, SiO2, MnO, and Cr2O3 are ranging from 5 × 10−7 to 9 × 10−7 m s−1, depending on diameters and components of inclusions.
Resistant Starch from Isolated White Sorghum Starch: Functional and Physicochemical Properties and Resistant Starch Retention After Cooking. A Comparative Study
Authors: Giuberti Gianluca , Marti Alessandra , Gallo Antonio , Grassi Silvia , Spigno Giorgia
Published: February 2019

In an effort to promote the formation of resistant starch (RS), four different modification methods are applied to isolated white sorghum (WS) starch by subjecting the latter to heat‐moisture treatment (RSa), annealing (RSb), hydrolysis through pullulanase debranching enzyme (RSc), and dual autoclaving‐cooling cycles (RSd). Functional and physicochemical properties, individual RS content, and the behavior after cooking in terms of apparent RS retention (aRSr) of samples (i.e., WS, RSa, RSb, RSc, and RSd) are compared. Differences in thermal and pasting properties, in the ratio of ordered starch to amorphous starch, along with lower solubility and swelling power values, and greater water absorption capacity are measured in the four RS ingredients when compared to native WS starch. All the four modification methods prove to be similarly effective in increasing the amount of RS with respect to native WS starch, with an average 30% increase. However, based on the aRSr values, analyses revealed that the greater heat stability after cooking was obtained for RSb (93.7%) and decreased in the order of RSb>RSc>RSa = RSd>WS. Present results shed light on the properties of modified WS starch as a potential heat‐stable source of RS for food applications.
The politics of fossil fuel subsidies and their reform: Implications for climate change mitigation
Authors: Skovgaard Jakob , van Asselt Harro
Published: February 2019

The production and consumption of fossil fuels need to decrease significantly to meet the 2015 Paris Agreement's ambitious climate change goals. However, fossil fuels continue to receive significant amounts of government support. Although reforming fossil fuel subsidies can yield climate change mitigation benefits, the specific international and domestic political context and political economy of fossil fuel subsidies means that such reform is not straightforward and may not be aligned with traditional climate politics. Our objective in this review article is to examine the implications of the politics of fossil fuel subsidies and their reform for climate change mitigation. The first step of examining these implications is to review existing studies on the size and impacts of global fossil fuel subsidies. Subsequently, we discuss the international politics of fossil fuel subsidies, including the emerging norm of fossil fuel subsidy reform, and the respective roles played by the international climate regime and several international economic institutions. Finally, we examine why fossil fuel subsidies are introduced and maintained at the domestic level, how fossil fuel subsidy reform has functioned in practice, and whether and how such reform could be conceived as an instrument for climate policy.

This article is categorized under:

The Carbon Economy and Climate Mitigation > Policies, Instruments, Lifestyles, Behavior

Policy and Governance > Private Governance of Climate Change
The Age and Origin of Karez Systems of Silk Road Oases around Turpan, Xinjiang, P.R. of China
Authors: Mächtle Bertil , Hecht Stefan , Manke Nicola , Kromer Bernd , Lindauer Susanne , Li Cheng-Sen , Li Ying , Wang Xiaofei , Bubenzer Olaf
Published: February 2019

Age and origin of ancient famous Karez water systems in the oases of the Turpan Basin are open questions in geoarchaeological and historical research. Four hypotheses exist: (a) invention during Han dynasty more than 2000 years ago, (b) transfer of technology from Persian Qanat’s more than 3000 years ago, (c) independent invention of local Uyghur people in the 15th century, and (d) late invention during the Chinese Qing dynasty (19th century). Our study dates, for the first time, 8 Karez systems by 14C from plants buried during the formation of Karez mounds, and interviews in order to record oral tradition. We found that the oldest investigated Karez systems originated in the Uyghurian Huihe dynasty (790–1755 AD), which coincides with the oral tradition. A second phase may have occurred during late Huihe/Qing dynasty (after 1755 AD), which may explain why information and the Uygurian term „Kan er jing“ went down in historic Chinese records. In conclusion, hypothesis (d) that oldest Karez systems were built during Qing dynasty has to be rejected because they are at least 600 years old. Instead, during the 3rd Chinese expansion in the 19th century AD the Karez system expanded and got maintenance. A review of regional palaeoclimatic proxies suggests that the origin and the maintenance of the Karez systems took place rather in more humid periods than in more arid ones. However, more research is needed on other Karez systems to test the pending hypotheses of a much older age.
Routes Beyond Gandhara: Buddhist Rock Carvings in the Context of the Early Silk Roads
Authors: van Aerde Marike
Published: February 2019

This chapter presents the first results and interpretations of a selected dataset of rock carvings from the Karakorum mountains. The research is focused on early Buddhist carvings and their spread and role within networks of the early Silk Roads in Central Asia from the 2nd–1st century BCE. The rock carvings and their archaeological context are studied to gain insight into routes from Gandhara through the Karakorum range. The first part presents the general aims and relevance. The second and third parts describe the analysis and interpretation of the Karakorum dataset, followed by the main points of discussion and conclusions to incite future investigations.
Living with Earthquakes along the Silk Road
Authors: Kázmér Miklós
Published: February 2019

Earthquakes are among the most horrible events of nature due to unexpected occurrence, for which no spiritual means are available for protection. The only way of preserving life and property is to prepare for the inevitable: applying earthquake-resistant construction methods. Zones of damaging earthquakes along the Silk Road are reviewed for seismic hazard and to understand the ways local civilizations coped with it during the past two thousand years. China and its wide sphere of cultural influence certainly had earthquake-resistant architectural practice, as the high number of ancient buildings, especially high pagodas, prove. A brief review of anti-seismic design and construction methods (applied both for wooden and masonry buildings) is given, in the context of earthquake-prone zones of Northern China. Muslim architects in Western China and Central Asia used brick and mortar to construct earthquake-resistant structural systems. Ancient Greek architects in Anatolia and the Aegean applied steel clamps embedded in lead casing to hold together columns and masonry walls during frequent earthquakes. Romans invented concrete and built all sizes of buildings as a single, non-flexible unit. Masonry, surrounding and decorating the concrete core of the wall, did not bear load. Concrete resisted minor shaking, yielding only to forces higher than fracture limits. Roman building traditions survived the Dark Ages, and 12th century Crusader castles erected in earthquake-prone Syria survive until today in reasonably good condition. Usage of earthquake-resistant technology depends on the perception of earthquake risks and on available financial resources. Earthquake-resistant construction practice is significantly more expensive than regular construction. Frequent earthquakes maintain safe construction practices, like the timber-laced masonry tradition in the Eastern Mediterranean throughout 500 years of political and technological development.
Dry and Humid Periods Reconstructed from Tree Rings in the Former Territory of Sogdiana (Central Asia) and Their Socio-economic Consequences over the Last Millennium
Authors: Opała-Owczarek Magdalena , Owczarek Piotr
Published: February 2019

One of the richest societies along the Silk Road developed in Sogdiana, located in present-day Tajikistan, Uzbekistan, and Kyrgyzstan. This urban civilisation reached its greatest prosperity during the golden age of the Silk Road (sixth to ninth century ce). Rapid political and economic changes, accelerated by climatic variations, were observed during last millennium in this region. The newly developed tree-ring-based reconstruction of precipitation for the past millennium revealed a series of dry and wet stages. During the Medieval Climate Anomaly (MCA), two dry periods occurred (900–1000 and 1200–1250), interrupted by a phase of wetter conditions. Distinct dry periods occurred around 1510–1650, 1750–1850, and 1920–1970, respectively. The juniper tree-ring record of moisture changes revealed that major dry and pluvial episodes were consistent with those indicated by hydroclimatic proxy data from adjacent areas. These climate fluctuations have had long- and short term consequences for human history in the territory of former Sogdiana.
The Key Role of Actors in the Agroecological Transition of Farmers: A Case-Study in the Tarn-Aveyron Basin
Authors: Ryschawy Julie , Sarthou Jean-Pierre , Chabert Ariane , Therond Olivier
Published: February 2019

For farmers, the transition towards agroecology implies redesigning both their production system and their commercialisation system. To engage in this type of transition, they need to develop new knowledge on practices adapted to local conditions, which will involve new actors in their network. This chapter explores the role of actors’ networks in the agroecological transition of farmers, with a particular focus on farming practices and modes of commercialisation. We held semi-structured interviews to understand: (i) individual farmers’ trajectories of change, considering practices at the farm and food system levels; (ii) the role of farmers’ networks in their involvement in the agroecological transition; and (iii) the role of their networks on a broader scale. In the Tarn-Aveyron basin, we interviewed ten dairy farmers and 50 actors interacting with them in connection with their farming practices. We focus on two dairy farmers’ trajectories: one who took a path towards agroecology, and the other who did not. We then show that the role of actors’ network is crucial in facilitating or impeding the agroecological transition. We highlight the importance of considering actors’ networks as a whole, including in the commercial sector, as having a key role in farmers’ shift towards agroecological transition.
Functional reduction of Feynman integrals
Authors: Tarasov O. V.
Published: February 2019

Abstract

A method for reducing Feynman integrals, depending on several kinematic variables and masses, to a combination of integrals with fewer variables is proposed. The method is based on iterative application of functional equations proposed by the author. The reduction of the one-loop scalar triangle and box integrals with massless internal propagators to simpler integrals is described in detail. The triangle integral depending on three variables is represented as a sum over three integrals depending on two variables. By solving the dimensional recurrence relations for these integrals, an analytic expression in terms of the2F1Gauss hypergeometric function and the logarithmic function was derived.

By using the functional equations, the one-loop box integral with massless internal propagators, which depends on six kinematic variables, was expressed as a sum of 12 terms. These terms are proportional to the same integral depending only on three variables different for each term. For this integral with three variables, an analytic result in terms of theF1Appell and2F1Gauss hypergeometric functions was derived by solving the recurrence relation with respect to the spacetime dimensiond. The reduction equations for the box integral with some kinematic variables equal to zero are considered.
Gravitational waves and electroweak baryogenesis in a global study of the extended scalar singlet model
Authors: Beniwal Ankit , Lewicki Marek , White Martin , Williams Anthony G.
Published: February 2019

Abstract

We perform a global fit of the extended scalar singlet model with a fermionic dark matter (DM) candidate. Using the most up-to-date results from the Planck measured DM relic density, direct detection limits from the XENON1T (2018) experiment, electroweak precision observables and Higgs searches at colliders, we constrain the 7-dimensional model parameter space. We also find regions in the model parameter space where a successful electroweak baryogenesis (EWBG) can be viable. This allows us to compute the gravitational wave (GW) signals arising from the phase transition, and discuss the potential discovery prospects of the model at current and future GW experiments. Our global fit places a strong upper and lower limit on the second scalar mass, the fermion DM mass and the scalar-fermion DM coupling. In agreement with previous studies, we find that our model can simultaneously yield a strong first-order phase transition and saturate the observed DM abundance. More importantly, the GW spectra of viable points can often be within reach of future GW experiments such as LISA, DECIGO and BBO.
Differentiation of Autoimmune Pancreatitis from Pancreatic Cancer Remains Challenging
Authors: Dickerson L. D. , Farooq A. , Bano F. , Kleeff J. , Baron R. , Raraty M. , Ghaneh P. , Sutton R. , Whelan P. , Campbell F. , Healey P. , Neoptolemos J. P. , Yip V. S.
Published: February 2019

Background

Autoimmune pancreatitis (AIP) is an uncommon form of chronic pancreatitis. Whilst being corticosteroid responsive, AIP often masquerades radiologically as pancreatic neoplasia. Our aim is to appraise demographic, radiological and histological features in our cohort in order to differentiate AIP from pancreatic malignancy.

Methods

Clinical, biochemical, histological and radiological details of all AIP patients 1997–2016 were analysed. The initial imaging was re‐reviewed according to international guidelines by three blinded independent radiologists to evaluate features associated with autoimmune pancreatitis and pancreatic cancer.

Results

There were a total of 45 patients: 25 in type 1 (55.5%), 14 type 2 (31.1%) and 6 AIP otherwise not specified (13.3%). The median (IQR) age was 57 (51–70) years. Thirty patients (66.6%) were male. Twenty‐six patients (57.8%) had resection for suspected malignancy and one for symptomatic chronic pancreatitis. Three had histologically proven malignancy with concurrent AIP. Two patients died from recurrent pancreatic cancer following resection. Multidisciplinary team review based on radiology and clinical history dictated management. Resected patients (vs. non‐resected group) were older (64 vs. 53, p = 0.003) and more frequently had co‐existing autoimmune pathologies (22.2 vs. 55.6%, p = 0.022). Resected patients also presented with less classical radiological features of AIP, which are halo sign (0/25 vs. 3/17, p = 0.029) and loss of pancreatic clefts (18/25 vs. 17/17, p = 0.017). There were no differences in demographic features other than age.

Conclusion

Despite international guidelines for diagnosing AIP, differentiation from pancreatic cancer remains challenging. Resection remains an important treatment option in suspected cancer or where conservative treatment fails.