bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors Associated With Preterm Delivery Among Women With Rheumatoid Arthritis and Women With Juvenile Idiopathic Arthritis
Authors: Smith Chelsey J. F. , Förger Frauke , Bandoli Gretchen , Chambers Christina D. 
Published: August 2018

ObjectivePregnant women with inflammatory arthritis may be at increased risk for preterm delivery (PTD), yet it is unclear what drives this risk. This aim of this prospective cohort study of pregnant women with rheumatoid arthritis (RA), juvenile idiopathic arthritis (JIA), or healthier comparison women was to analyze the independent effects of maternal disease activity, medication use, and comorbid pregnancy conditions on PTD risk.MethodsWomen were enrolled before 19 weeks completed gestation as part of the Organization of Teratology Information Specialists (OTIS) Autoimmune Disease in Pregnancy Project. Data on pregnancy events, medications, disease activity, and outcomes were obtained by maternal report and validated by medical records. Poisson regression with robust standard errors estimated risk ratios (RR), multivariable adjusted risk ratios (ARRs), and 95% confidence intervals (95% CIs).ResultsA total of 657 women with RA, 170 with JIA, and 564 comparison women without autoimmune disease who delivered live born infants, from 2004 to 2017 were included for analysis. Both the RA and JIA groups had an increased risk of PTD versus the comparison group (RR 2.09 [95% CI 1.50–2.91] and RR 1.81 [95% CI 1.14–2.89], respectively). Active RA at enrollment (ARR 1.58 [95% CI 1.10–2.27]) and any time during pregnancy (ARR 1.52 [95% CI 1.06–2.18]) was associated with PTD. Corticosteroid use in every trimester was associated with an approximate 2‐ to 5‐fold increased risk for PTD for both arthritis groups, independent of disease activity.ConclusionWomen with RA and women with JIA are at increased risk for PTD. Maternal disease activity and corticosteroid use may contribute to some of this excess risk.
Polarity‐Switchable Symmetric Graphite Batteries with High Energy and High Power Densities
Authors: Wang Gang , Wang Faxing , Zhang Panpan , Zhang Jian , Zhang Tao , Müllen Klaus , Feng Xinliang 
Published: August 2018

AbstractMultifunctional batteries with enhanced safety performance have received considerable attention for their applications at extreme conditions. However, few batteries can endure a mix‐up of battery polarity during charging, a common wrong operation of rechargeable batteries. Herein, a polarity‐switchable battery based on the switchable intercalation feature of graphite is demonstrated. The unique redox‐amphoteric intercalation behavior of graphite allows a reversible switching of graphite between anode and cathode, thus enabling polarity‐switchable symmetric graphite batteries. The large potential gap between anion and cation intercalation delivers a high midpoint device voltage (≈average voltage) of ≈4.5 V. Further, both the graphite anode and cathode are kinetically activated during the polarity switching. Consequently, polarity‐switchable symmetric graphite batteries exhibit a remarkable cycling stability (96% capacity retention after 500 cycles), a high power density of 8.66 kW kg−1, and a high energy density of 227 Wh kg−1 (calculated based on the total weight of active materials in both anode and cathode), which are superior to other symmetric batteries and recently reported dual‐graphite or dual‐carbon batteries. This work will inspire the development of new multifunctional energy‐storage devices based on novel materials and electrolyte systems.
One‐Step Solvent‐Free Strategy for Covalently Attached, Substrate‐Independent Transparent Slippery Coating
Authors: Zhang Guangyu , Liang Bang , Zhong Zhenxing , Huang Yan , Su Zhaohui 
Published: August 2018

AbstractSlippery liquid‐infused porous surfaces (SLIPS) have attracted interest in recent years due to their outstanding liquid‐repellency. However, the infused liquid may be lost over time. Here, a one‐step fabrication of robust slippery coatings that are water repellent is reported. By crosslinking a mixture of monovinyl‐ and divinyl‐terminated poly(dimethylsiloxane) (PDMS) with poly(methylhydrosiloxane) via a hydrosilylation reaction, crosslinked coatings composed of PDMS skeleton and tethered, liquidlike PDMS pendant chains are prepared. The coatings are durable, transparent, and slippery, displaying extremely low water contact angle hysteresis, fostering the sliding motion of adhered water droplets. Produced via a simple, solvent‐free process requiring only commercially available reagents, the fluorine‐free coatings can be applied on a variety of substrates, opening the door to many industrial applications.
Transition Metal‐Controlled Direct Regioselective Intermolecular Amidation of C−H Bonds with Azodicarboxylates: Scope, Mechanistic Studies, and Applications
Authors: Bai He‐Yuan , Fu Xin , Pan Jin‐Long , Ma Hai‐Qian , Chen Zhi‐Min , Ding Tong‐Mei , Zhang Shu‐Yu 
Published: August 2018

AbstractA simple and efficient transition metal‐catalyzed C−H amidation with azodicarboxylates has been developed. Under silver catalysis, the amide substrates undergo regioselective C−H amidation at C5‐position of the quinoline. Conversely, with palladium as the catalyst, the reaction gave β‐C(sp3)−H amidation products via the activation of methylene C(sp3)−H bonds. Mechanistic studies suggested that the single‐electron‐transfer and organometallic mechanism pathways gave rise to these surprising and distinct outcomes. Based on the mechanistic analysis, we designed a palladium‐catalyzed/silver‐promoted direct intermolecular β‐C(sp3)−H amidation to activate the methylene C(sp3)−H bonds of 5‐chloro‐8‐aminoquinoline (CQ)‐protected aliphatic amides with azodicarboxylates. Both catalytic protocols provide alternative, convenient, and simple strategies for efficiently accessing structurally unique C−N bond‐containing compounds in a regioselective manner.magnified image
Carbocation Catalyzed Bromination of Alkyl Arenes, a Chemoselective sp3vs. sp2 C−H functionalization.
Authors: Ni Shengjun , El Remaily Mahmoud Abd El Aleem Ali Ali , Franzén Johan 
Published: August 2018

AbstractThe versatility of the trityl cation (TrBF4) as a highly efficient Lewis acid organocatalyst is demonstrated in a light induced benzylic brominaion of alkyl‐arenes under mild conditions. The reaction was conducted at ambient temperature under common hood light (55 W fluorescent light) with catalyst loadings down to 2.0 mol% using N‐bromosuccinimide (NBS) as the brominating agent. The protocol is applicable to an extensive number of substrates to give benzyl bromides in good to excellent yields. In contrast to most previously reported strategies, this protocol does not require any radical initiator or extensive heating. For electron‐rich alkyl‐arenes, the trityl ion catalyzed bromination could be easily switched between benzylic sp3 C−H functionalization and arene sp2 C−H functionalization by simply alternating the solvent. This chemoselective switch allows for high substrate control and easy preparation of benzyl bromides and bromoarenes, respectively. The chemoselective switch was also applied in a one‐pot reaction of 1‐methylnaphthalene for direct introduction of both sp3 C−Br and sp2 C−Br functionality.magnified image
Partial mycoheterotrophy in the leafless orchid Cymbidium macrorhizon
Authors: Suetsugu Kenji , Ohta Tamihisa , Tayasu Ichiro 
Published: August 2018

Premise of the StudyThe evolution of full mycoheterotrophy is one of the most interesting topics within plant evolution. The leafless orchid Cymbidium macrorhizon is often assumed to be fully mycoheterotrophic even though it has a green stem and fruit capsule. Here, we assessed the trophic status of this species by analyzing the chlorophyll content and the natural 13C and 15N abundance in the sprouting and the fruiting season.MethodsThe chlorophyll content was measured in five sprouting and five fruiting individuals of C. macrorhizon that were co‐occurring. In addition, their 13C and 15N isotopic signatures were compared with those of neighboring autotrophic and partially mycoheterotrophic reference plants.Key ResultsFruiting individuals of C. macrorhizon were found to contain a remarkable amount of chlorophyll compared to their sprouting counterparts. In addition, the natural abundance of 13C in the tissues of the fruiting plants was slightly depleted relative to the sprouting ones. Linear two‐source mixing model analysis revealed that fruiting C. macrorhizon plants obtained approximately 73.7 ± 2.0% of their total carbon from their mycorrhizal fungi when the sprouting individuals were used as the 100% carbon gain standard.ConclusionsOur results indicated that despite its leafless status, fruiting plants of C. macrorhizon were capable of fixing significant quantities of carbon. Considering the autotrophic carbon gain increases during the fruiting season, its photosynthetic ability may contribute to fruit and seed production. These results indicate that C. macrorhizon should, therefore, be considered a partially mycoheterotrophic species rather than fully mycoheterotrophic, at least during the fruiting stage.
Lifetime socioeconomic status and early life microbial environments predict adult blood telomere length in the Philippines
Authors: Tennyson Robert L. , Gettler Lee T. , Kuzawa Christopher W. , Hayes M. Geoffrey , Agustin Sonny S. , Eisenberg Dan T.A. 
Published: August 2018

AbstractObjectivesPsychosocial stress is postulated to hasten senescence in part by accelerating the shortening of telomere length (TL). One pathway through which this may happen is via increasing inflammation and innate immune system activation—a pathway which recent studies suggest acts more strongly for those who grew up in low microbial environments. Thus, we hypothesized that: (1) Psychosocial stress will be inversely associated with TL, (2) early life microbial environments will predict TL, and (3) microbial environments will moderate the association between psychosocial stress and TL.MethodsWe utilized data from the Cebu Longitudinal Health and Nutrition Survey based in the Philippines (N = 1410). We determined early life microbial environments by season of birth and exposure to animal feces. Psychosocial stress measures included perceived stress in adulthood, lifetime socioeconomic status (SES), and parental instability in childhood. TL was measured in blood from young adults by qPCR.ResultsContrary to predictions, we found that higher SES was associated with shorter TL and no association of TL with the other stress variables. Individuals born in the higher microbial exposure season had shorter TL, but early life microbial environments did not moderate the association between psychosocial stress and TL.ConclusionsThe unexpected inverse association between SES and TL suggests that higher SES, while indexing lower psychosocial stress, may impact TL more strongly through nonstress factors in the Philippines, such as unhealthy behavior. The inverse association between microbial environments and TL is consistent with other evidence connecting early life infections to decreased life expectancies.
A Photonic Nanojet as Tunable and Polarization‐Sensitive Optical Tweezers
Authors: Kovrov Aleksandr , Novitsky Andrey , Karabchevsky Alina , Shalin Alexander S. 
Published: August 2018

AbstractThe ability to manipulate small objects with focused laser beams has opened a venue for investigating dynamical phenomena relevant to both fundamental and applied sciences. However, manipulating nano‐sized objects requires subwavelength field localization, provided by auxiliary nano‐ and microstructures. Particularly, dielectric microparticles can be used to confine light to an intense beam with a subwavelength waist, called a photonic nanojet (PNJ), which can provide sufficient field gradients for trapping nano‐objects. Herein, the scheme for wavelength‐tunable and nanoscale‐precise optical trapping is elaborated, and the possibility of lateral nanoparticle movement using the PNJ's side lobes is shown for the first time. In addition, the possibility of subwavelength positioning using polarization switching is shown. The estimated stability with respect to Brownian motion is higher compared to conventional optical trapping schemes.
Improving the thermal stability of azoreductase from Halomonas elongata by introducing a disulfide bond via site‐directed mutagenesis
Authors: Nakhaee Narjes , Asad Sedigheh , Khajeh Khosro , Arab Seyed Shahriar , Amoozegar Mohammad Ali 
Published: August 2018

AbstractAzoreductases mainly reduce azo dyes, the largest class of colorants, to colorless aromatic amines. AzoH, a new azoreductase from the halophilic bacterium, Halomonas elongata, has been recently cloned and expressed in Escherichia coli. The aim of this study was to improve thermal stability of this enzyme by introducing new disulfide bonds. Since X‐ray crystallography was not available, homology modeling and molecular dynamics was used to construct the enzyme three‐dimensional structure. Potential disulfide bonds for increasing thermal stability were found using DIScover online software. Appropriate mutations (L49C/D108C) to form a disulfide bond were introduced by the Quik‐Change method. Mutant protein expressed in E. coli showed increased thermal stability at 50 °C (increased half‐life from 12.6 Min in AzoH to 26.66 Min in a mutated enzyme). The mutated enzyme could also tolerate 5% (w/v) NaCl and retained 30% of original activity after 24 H incubation, whereas the wild‐type enzyme was completely inactivated. According to circular dichroism studies, the secondary structure was not altered by this mutation; however, a blue shift in intrinsic florescent graph revealed changes in the tertiary structure. This is the first study to improve thermal stability and salt tolerance of a halophilic azoreductase.
Overall survival before and after centralization of gastric cancer surgery in the Netherlands
Authors: van Putten M , Nelen S D , Lemmens V E P P , Stoot J H M B , Hartgrink H H , Gisbertz S S , Spillenaar Bilgen E J , Heisterkamp J , Verhoeven R H A , Nieuwenhuijzen G A P 
Published: August 2018

Abstract

Background
Centralization of surgery has been shown to improve outcomes for oesophageal and pancreatic cancer, and has been implemented for gastric cancer since 2012 in the Netherlands. This study evaluated the impact of centralizing gastric cancer surgery on outcomes for all patients with gastric cancer.

Methods
Patients diagnosed with non-cardia gastric adenocarcinoma in the intervals 2009–2011 and 2013–2015 were selected from the Netherlands Cancer Registry. Clinicopathological data, treatment characteristics and mortality were assessed for the periods before (2009–2011) and after (2013–2015) centralization. Cox regression analyses were used to assess differences in overall survival between these intervals.

Results
A total of 7204 patients were included. Resection rates increased slightly from 37·6 per cent before to 39·6 per cent after centralization (P = 0·023). Before centralization, 50·1 per cent of surgically treated patients underwent gastrectomy in hospitals that performed fewer than ten procedures annually, compared with 9·2 per cent after centralization. Patients who had gastrectomy in the second interval were younger and more often underwent total gastrectomy (29·3 per cent before versus 41·2 per cent after centralization). Thirty-day postoperative mortality rates dropped from 6·5 to 4·1 per cent (P = 0·004), and 90-day mortality rates decreased from 10·6 to 7·2 per cent (P = 0·002). Two-year overall survival rates increased from 55·4 to 58·5 per cent among patients who had gastrectomy (P = 0·031) and from 27·1 to 29·6 per cent for all patients (P = 0·003). Improvements remained after adjustment for case mix; however, adjustment for hospital volume attenuated this association for surgically treated patients.

Conclusion
Centralization of gastric cancer surgery was associated with reduced postoperative mortality and improved survival.
Long-term outcomes of endovenous laser ablation and conventional surgery for great saphenous varicose veins
Authors: Wallace T , El-Sheikha J , Nandhra S , Leung C , Mohamed A , Harwood A , Smith G , Carradice D , Chetter I 
Published: August 2018

Abstract

Background
Clinical guidelines recommend endovenous laser ablation (EVLA) over surgery based on short-term evidence, yet there are few studies reporting mid- to long-term outcomes. The aim of this study was to report the 5-year outcomes from an RCT of surgery versus EVLA for treatment of symptomatic great saphenous varicose veins.

Methods
Patients with symptomatic varicose veins due to great saphenous vein (GSV) incompetence were followed up 5 years after enrolment in a randomized trial of either surgery (saphenofemoral junction ligation, GSV strip to the knee and multiple avulsions of varicosities) or EVLA plus multiple avulsions. Outcomes included: clinical recurrence, defined as new varicose veins greater than 3 mm in diameter; Venous Clinical Severity Score (VCSS); quality of life measured by means of Short Form 36, EuroQol Five Dimensions (EQ-5D™) and Aberdeen Varicose Vein Questionnaire (AVVQ); patient satisfaction; and duplex ultrasound examination (DUS) findings.

Results
Some 218 of the 276 patients enrolled in the trial (79·0 per cent) were available for follow-up. Clinical recurrence was more frequent following surgery than EVLA at 5 years (34·3 versus 20·9 per cent; P = 0·010). Both groups demonstrated sustained significant improvements at 5 years over baseline in VCSS (surgery: median (i.q.r.) 1 (0–2) from 4 (3-5), P &lt; 0·001; EVLA: 0 (0–1) from 4 (3-5), P &lt; 0·001), AVVQ (surgery: 4·59 (0·56–9·78) from 13·69 (9·81–18·11), P &lt; 0·001; EVLA: 3·35 (0·17 to 6·55) from 12·73 (9·41–17·32), P &lt; 0·001) and EQ-5D™ (surgery: 1·000 (0·796–1·000) from 0·859 (0·796–1·000), P = 0·002; EVLA: 1·000 (0·796–1·000) from 0·808 (0·796–1·000), P = 0·002). VCSS was better for EVLA than surgery at 5 years (P = 0·031). Technical success assessed by DUS remained high at 5 years (85·4 per cent for surgery and 93·2 per cent for EVLA; P = 0·074). DUS-detected anatomical patterns of recurrence differed between the groups.

Conclusion
EVLA was more effective than surgery in preventing clinical recurrence 5 years after treatment of great saphenous varicose veins. Patient-reported outcome measures were similar. Registration number: NCT00759434 (http://www.clinicaltrials.gov).
Enhanced Catalytic Properties of Molybdenum Promoted Mesoporous Cobalt Oxide: Structure‐Surface‐Dependent Activity for Selective Synthesis of 2‐Substituted Benzimidazoles
Authors: Weerakkody Chandima , Rathnayake Dinithi , He Junkai , Dutta Biswanath , Kerns Peter , Achola Laura , Suib Steven L. 
Published: August 2018

AbstractHigh‐valent molybdenum ions were substituted into the cobalt oxide lattice through a one step, sol‐gel method and investigated for selective synthesis of 2‐substituted benzimidazoles. Catalyst synthesis involves surfactant assisted soft templating inverse micelle method, which forms mesopores by interconnected intraparticle voids. Substitutional doping of Mo6+ resulted in materials with modified structural, morphological, surface, and redox properties. The catalytic activity increased with Mo concentration until an optimum amount (3 % Mo incorporation). Modified material shows lattice expansion, increased surface oxygen vacancies, and high surface area, which are responsible for the higher catalytic activity in selective benzimidazole synthesis reaction. A strong correlation between surface properties of the catalyst and the product selectivity was observed and plausible mechanistic and kinetic data are proposed and collected, respectively.
In Situ Growth of a Feather‐like MnO2 Nanostructure on Carbon Paper for High‐Performance Rechargeable Sodium‐Ion Batteries
Authors: Li Huan , Liu Anmin , Zhao Shuai , Guo Zhanglin , Wang Nannan , Ma Tingli 
Published: August 2018

AbstractRecently, sodium‐ion batteries have attracted great attention, owing to the rich resource and low cost. In the present work, a feather‐like MnO2 nanostructure was prepared directly on carbon paper by using a rapid and simple hydrothermal route for the first time. The formation mechanism was proposed by investigating the intermediate products during the reaction. When applied as an anode for a sodium‐ion battery, the feather‐like MnO2 nanostructure on carbon paper exhibited a high discharge capacity, good rate reversibility, and long‐term cycling stability. A high specific capacity of approximately 300 mAh g−1 could be obtained even after cycling 400 times with a current density of 0.1 A g−1. Furthermore, the Na+ storage mechanism of MnO2 on carbon paper in the sodium‐ion battery was also investigated in this work. Such high performance can be attributed to the porous structure of the substrate and high specific surface area of the feather‐like nanostructure.
Synthesis of 3D N, S Dual‐Doped Porous Carbons with Ultrahigh Surface Areas for Highly Efficient Oxygen Reduction Reactions
Authors: Liu Yan‐Zhen , Li Yong‐Feng , Yuan Shu‐Xia , Chen Shuai , Wang Cong‐Wei , Li Xiao‐Ming , Su Fang‐Yuan , Chen Cheng‐Meng 
Published: August 2018

AbstractReplacing rare and expensive metal electrocatalysts with efficient, low‐cost, and stable ones for the oxygen reduction reactions (ORR) is of significant importance. Herein, we report a novel scalable synthesis of three‐dimensional (3D) N, S dual‐doped porous carbons (NSPCs) with ultrahigh surface areas that can serve as highly active, metal‐free electrocatalysts for the ORR. The NSPCs are prepared by synthesizing 3D black pillar foams from a mixture containing p‐nitroaniline and concentrated sulfuric acid, and subsequently carbonization under an Ar atmosphere. This method not only avoids the use of any template, but also allows for the simultaneous optimization of both porous structures and surface functionalities by tuning the carbonization temperature. Owing to the synergy of the tailored porous structure and N, S dual‐doping, the NSPC pyrolyzed at 1000 °C exhibits a good catalytic activity toward the ORR with a half‐wave potential of −0.10 V vs. Ag/AgCl and a high four electron (4e−) oxygen reduction selectivity in an alkaline medium, which is identical to that of the commercial 20 wt% Pt/C catalyst, and outperforms most previously reported metal‐free catalysts. The NSPCs also show good energy‐storage performance for advanced supercapacitors.
Fluorine‐Containing Branched Sulfonated Polyimide Membrane for Vanadium Redox Flow Battery Applications
Authors: Yang Pan , Xuan Sensen , Long Jun , Wang Yanlin , Zhang Yaping , Zhang Hongping 
Published: August 2018

AbstractA series of fluorine‐containing branched sulfonated polyimide (Fb‐SPI) membranes with different degrees of branching (0–12 %) were synthesized through polycondensation. The chemical structure of Fb‐SPI‐10 membrane was confirmed using ATR‐FTIR and 1H NMR spectroscopy. The physico‐chemical properties of Fb‐SPI membranes were systematically investigated and compared to linear SPI (l‐SPI) and Nafion 117 membranes. The vanadium‐ion permeabilities of Fb‐SPI membranes (2.45–0.99×10−7 cm2 min−1) are much lower than that of Nafion 117 (17.1×10−7 cm2 min−1) membranes. Besides, the chemical stability of Fb‐SPI membranes is superior to that of l‐SPI membranes. During 500‐time continuous cyclic charge‐discharge measurements, the VRFB assembled with a Fb‐SPI‐10 membrane shows higher coulombic efficiency (98.4–99.7 %), higher or close energy efficiency (69.0–79.7 %) from 40 to 80 mA cm−2, and higher or close capacity retention (52.8–100 %) from 40 to 70 mA cm−2 compared with a device using a Nafion 117 membrane. All of these results demonstrate that the as‐selected Fb‐SPI‐10 membrane has promising potential for VRFB applications.