bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dual Photoredox/Copper Catalysis for the Remote C(sp3)−H Functionalization of Alcohols and Alkyl Halides by N‐Alkoxypyridinium Salts
Authors: Bao Xu , Wang Qian , Zhu Jieping 
Published: December 2018

AbstractUnder mild dual photoredox/copper catalysis, the reaction of N‐alkoxypyridinium salts with readily available silyl reagents (TMSN3, TMSCN, TMSNCS) afforded δ‐azido, δ‐cyano, and δ‐thiocyanato alcohols in high yields. The reaction went through a domino process involving alkoxy radical generation, 1,5‐hydrogen atom transfer (1,5‐HAT) and copper‐catalyzed functionalization of the resulting C‐centered radical. Conditions for catalytic enantioselective δ‐C(sp3)−H cyanation were also documented.
Modelling and analysis of impact forces acting on elbow in gas–liquid slug flow
Authors: Xiao Fei , Jing Jiaqiang , Han Li , Yang Lu , Wang Shuai 
Published: December 2018

AbstractThe impact forces caused by gas–liquid slug flow can lead to the vibration of process system or fatigue failure of pipe fittings. In this study, a piston‐flow‐model coupling with slug model is developed to calculate the impact forces, which can contribute to the structure design and flow assurance. An experiment installation is installed to study the characteristics of slug flow and validate the reliability of the model. The accuracy of this model is above 90% for the superficial velocity of gas below 2 m/s, whereas the average deviation is 29.2% for the cases of superficial velocity of gas above 2 m/s. The modified model addressing the liquid holdup agrees well with the experimental data, of which the average deviation is 6.25%.
A Novel Grading Strategy for Team‐Based Learning Exercises in a Hands‐on Course in Molecular Biology for Senior Undergraduate Underrepresented Students in Medicine Resulted in Stronger Student Performance
Authors: Carrasco Gonzalo A. , Behling Kathryn C. , Lopez Osvaldo J. 
Published: December 2018

AbstractWe developed a hands‐on course in molecular biology for undergraduate underrepresented in medicine (URM) students. To incentivize student preparation for team‐based learning (TBL) activities, we implemented a novel grading schema that requires a minimum individual readiness assurance test (iRAT) score to share the team group readiness assurance test (gRAT) score. Fifty‐one students participated in this 2‐year study and were divided in teams of five or six students that worked throughout the course on a unique, hands‐on project and also participated in TBL exercises. In the laboratory sessions, students isolated RNA from cultured neuronal cells, synthesized complementary DNA (cDNA), and used gene sequencing to identify a gene relevant in human health and disease. Student participation in TBL was quantified and correlated with performance on individual iRATs and the course final examination. We found that implementation of the novel incentive structure lowered the variance of TBL scores (iRAT and gRAT) and strengthened the correlation between final examination scores and either iRAT scores or percentage participation in TBL. Subgroup analysis showed that with the new grading schema, stronger students benefited more from the gRAT exercises, while more poorly performing students were better helped by individual preparation prior to the iRAT exercise. A combination of two active learning strategies, TBL and hands‐on sessions, may strengthen student acquisition of course content and promote teamwork skills. The new incentive structure seems to reduce the disparity in knowledge amongst our students as demonstrated by the reduced iRAT and gRAT score variances. © 2018 International Union of Biochemistry and Molecular Biology, 47(2): 115–123, 2019.
Survival of the fittest: The impact of eco‐certification and reputation on firm performance
Authors: Fanasch Patrizia 
Published: December 2018

AbstractOwing to the increased trend for organic products and the concept of sustainable development, firms must invest in valuable and unique resources to achieve long‐term success and gain competitive advantages. Building on insights from the resource‐based view and natural‐resource‐based view of the firm, the study focuses on the contribution of corporate reputation and eco‐certification as intangible influences on corporate performance. Duration analysis is applied on a sample of 1,572 German wineries over the period 1994 to 2017. The results indicate that individual reputation and eco‐certification have a statistically significant and positively impact on corporate performance, whereas there is no clear evidence of this relationship for collective reputation. In addition, especially those firms with high individual reputation benefit most from eco‐certification. These results are robust across different parametric and semiparametric model estimations.
Selective Delivery of Doxorubicin to EGFR+ Cancer Cells by Cetuximab–DNA Conjugates
Authors: Liu Tianqiang , Song Ping , Märcher Anders , Kjems Jørgen , Yang Chuanxu , Gothelf Kurt V. 
Published: December 2018

AbstractDoxorubicin is a hydrophobic anticancer drug that has poor selectivity, due to the lack of active targeting capability. Here, learning lessons from the success of antibody–drug conjugates, we have designed a new doxorubicin delivery system without conjugating doxorubicin to antibody directly. In this setup, cetuximab, an antibody that targets the epidermal growth factor receptor (EGFR) in cancer cells, was conjugated to a single‐stranded DNA with a carefully designed sequence in a site‐selective manner by using the DNA‐templated protein conjugation (DTPC) method. The DNA duplex in the conjugates serves as a carrier of doxorubicin through noncovalent intercalation, and cetuximab functions as the targeting agent; this could drastically decrease systemic toxicity and potentially avoid under‐ or overdosing. The size of conjugates loaded with doxorubicin was about 8.77 or 16.61 nm when characterized by dynamic light scattering and atomic force microscopy, respectively. In vitro cytotoxicity and selective cancer cell killing was investigated against two EGFR+ cell lines (KB and MDA‐MB‐231) and one EGFR− cell line (NIH‐3T3). Cytotoxicity and flow cytometry data showed that doxorubicin loaded in cetuximab–DNA conjugates was more potent in terms of cell cytotoxicity than free doxorubicin in EGFR‐overexpressed cell lines, thus suggesting that the conjugates were more selectively and easily taken up into cells, followed by rapid release of doxorubicin from the system into the cytoplasm from endosomes.
A comparison of valve‐in‐valve transcatheter aortic valve replacement in failed stentless versus stented surgical bioprosthetic aortic valves
Authors: Choi Charles H. , Cheng Vivian , Malaver Diego , Kon Neal , Kincaid Edward H. , Gandhi Sanjay K. , Applegate Robert J. , Zhao David X. M. 
Published: December 2018

AbstractObjectivesThe objectives of this study were to compare short‐ and intermediate‐term clinical outcomes, procedural complications, TAVR prosthesis hemodynamics, and paravalvular leak (PVL) in stentless and stented groups.BackgroundValve‐in‐valve (ViV) transcatheter aortic valve replacement (TAVR) is an alternative to surgical redo for bioprosthetic valve failure. There have been limited data on ViV in stentless surgical valves.MethodsWe retrospectively analyzed 40 patients who underwent ViV TAVR in prior surgical bioprosthetic valves at Wake Forest Baptist Medical Center from October 2014 to September 2017. Eighty percent (32/40) ViV TAVRs were in stentless, while 20% (8/40) were in stented bioprosthetic valves.ResultsThe primary mode of bioprosthetic valve failure for ViV implantation in the stentless group was aortic insufficiency (78%, 25/32), while in the stented group was aortic stenosis (75%, 6/8). The ViV procedure success was 96.9% (31/32) in stentless group and 100% in stented group (8/8). There were no significant differences in all‐cause mortality at 30 days between stentless and stented groups (6.9%, 2/31 versus 0%, 0/8, P = 0.33) and at 1 year (0%, 0/25 versus 0%, 0/5). In the stentless group, 34.4% (11/32) required a second valve compared to the stented group of 0% (0/8). There was a significant difference in the mean aortic gradient at 30‐day follow‐up (12.33 ± 6.33 mmHg and 22.63 ± 8.45 mmHg in stentless and stented groups, P < 0.05) and at 6‐month follow‐up (9.75 ± 5.07 mmHg and 24.00 ± 11.28 mmHg, P < 0.05), respectively.ConclusionsViV in the stentless bioprosthetic aortic valve has excellent procedural success and intermediate‐term results. Our study shows promising data that may support the application of TAVR in stentless surgical aortic valve. However, further and larger studies need to further validate our single center's experience.
Synthesis of [7]Helicene Enantiomers and Exploratory Study of Their Conversion into Helically Chiral Iodoarenes and Iodanes
Authors: Antien Kevin , Pouységu Laurent , Deffieux Denis , Massip Stéphane , Peixoto Philippe A. , Quideau Stéphane 
Published: December 2018

AbstractThe facile and convenient preparation of both enantiomers of a [7]helicene scaffold from inexpensive (l)‐(+)‐tartaric acid and 4‐methylstyrene is described. These helical structures were transformed into bis‐iodinated ether derivatives in order to explore their potential as precursors of novel chiral organoiodane reagents or as iodoarene pre‐catalysts. Promising results were obtained in hydroxylative phenol dearomatization/[4+2] cycloaddition cascade and dearomative spirolactonization reactions with encouraging enantiomeric excesses.
Anti‐noise image source identification
Authors: Liu Yuying , Huang Yonggang , Zhang Jiao , Shen Hualei 
Published: December 2018

SummaryImage source identification plays an important role in image forensics. Traditional image source identification techniques rely on the assumption that the training datasets are well labeled. However, in the real world, this assumption may not be the truth, and some noisy samples may exist in the training datasets. In this paper, firstly, we theoretically investigate the influence of noisy samples to the identification performance. Then, a new image source identification approach, namely, Anti‐noise Image Source Identification (AISI), is proposed to deal with those noisy samples. AISI has three steps, ie, noise level evaluation, noise level based sampling, and multi‐classification. Noise level evaluation aims to assign each sample with a noise level that indicates the probability of being noisy. The basic idea of noise level based sampling is to sample images according to their noise levels. We provide a theoretically justification to demonstrate the effectiveness of AISI. Experiments conducted on a real‐world image collection confirm that the proposed AISI can alleviate the influence of noisy samples and can improve the identification accuracy while noise exists.
Solar Water Oxidation by a Visible‐Light‐Responsive Tantalum/Nitrogen‐Codoped Rutile Titania Anode for Photoelectrochemical Water Splitting and Carbon Dioxide Fixation
Authors: Nakada Akinobu , Uchiyama Tomoki , Kawakami Nozomi , Sahara Go , Nishioka Shunta , Kamata Ryutaro , Kumagai Hiromu , Ishitani Osamu , Uchimoto Yoshiharu , Maeda Kazuhiko 
Published: December 2018

AbstractThe front cover artwork is provided by the Ishitani and Maeda group at the School of Science at the Tokyo Institute of Technology (Japan). The image shows CO2 reduction and H2 production coupled to water oxidation by a photoelectrochemical system based on a Ta/N codoped rutile TiO2 anode under sunlight. Read the full text of the Article at 10.1002/cptc.201800157.
Energy‐efficient relay deployment in cellular systems using fractional frequency reuse and transmit antenna selection techniques
Authors: Oh Hyun Seob , Jeong Dong Geun , Jeon Wha Sook 
Published: December 2018

SummaryTo cope with the steep surge in mobile traffic, network operators are now expanding their infrastructure for mobile access networks. However, since energy costs and greenhouse gas emissions are a large burden to network operators, they are making great efforts to improve the energy efficiency (EE) of their networks by promising techniques, including relaying and multiple‐input multiple‐output (MIMO). Relaying technique can considerably improve the EE when the interference between base stations (BSs) and relay stations (RSs) is effectively coordinated by an elaborate relay deployment using the fractional frequency reuse (FFR) technique. Also, MIMO techniques improve the radio channel quality through diversity gains, so the system capacity and the EE can be improved. Therefore, a combination of relaying/MIMO techniques can be considered to achieve the higher performance, particularly, if the system complexity and costs of using such techniques are low. Since the transmit antenna selection (TAS), one of MIMO techniques, can provide a sufficient transmit diversity gain and satisfy the requirements for low complexity and cost (thus, practical), the TAS is recommended for use with the relaying technique. In this paper, for an energy‐efficient relay deployment using FFR and TAS techniques, we derive the EE and the resource partitioning according to RS positions and the number of BS antennas by a mathematical analysis. Then, the optimal RS positions according to the number of antennas can be determined by an optimization approach. The numerical and simulation results indicate that the proposed analysis method can efficiently analyze the EE and locate the RSs.
Compounding effects of climate change reduce population viability of a montane amphibian
Authors: Kissel Amanda M. , Palen Wendy J. , Ryan Maureen E. , Adams Michael J. 
Published: December 2018

AbstractAnthropogenic climate change presents challenges and opportunities to the growth, reproduction, and survival of individuals throughout their life cycles. Demographic compensation among life‐history stages has the potential to buffer populations from decline, but alternatively, compounding negative effects can lead to accelerated population decline and extinction. In montane ecosystems of the U.S. Pacific Northwest, increasing temperatures are resulting in a transition from snow‐dominated to rain‐dominated precipitation events, reducing snowpack. For ectotherms such as amphibians, warmer winters can reduce the frequency of critical minimum temperatures and increase the length of summer growing seasons, benefiting post‐metamorphic stages, but may also increase metabolic costs during winter months, which could decrease survival. Lower snowpack levels also result in wetlands that dry sooner or more frequently in the summer, increasing larval desiccation risk. To evaluate how these challenges and opportunities compound within a species’ life history, we collected demographic data on Cascades frog (Rana cascadae) in Olympic National Park in Washington state to parameterize stage‐based stochastic matrix population models under current and future (A1B, 2040s, and 2080s) environmental conditions. We estimated the proportion of reproductive effort lost each year due to drying using watershed‐specific hydrologic models, and coupled this with an analysis that relates 15 yr of R. cascadae abundance data with a suite of climate variables. We estimated the current population growth (λs) to be 0.97 (95% CI 0.84–1.13), but predict that λs will decline under continued climate warming, resulting in a 62% chance of extinction by the 2080s because of compounding negative effects on early and late life history stages. By the 2080s, our models predict that larval mortality will increase by 17% as a result of increased pond drying, and adult survival will decrease by 7% as winter length and summer precipitation continue to decrease. We find that reduced larval survival drives initial declines in the 2040s, but further declines in the 2080s are compounded by decreases in adult survival. Our results demonstrate the need to understand the potential for compounding or compensatory effects within different life history stages to exacerbate or buffer the effects of climate change on population growth rates through time.
Revisiting Scientific Issues for Industrial Applications of Lithium–Sulfur Batteries
Authors: Liu Bo , Fang Ruyi , Xie Dong , Zhang Wenkui , Huang Hui , Xia Yang , Wang Xiuli , Xia Xinhui , Tu Jiangping 
Published: December 2018

Inspired by high theoretical energy density (~2600 W h kg−1) and cost‐effectiveness of sulfur cathode, lithium–sulfur batteries are receiving great attention and considered as one of the most promising next‐generation high‐energy‐density batteries. However, over the past decades, the energy density and reliable safety levels as well as the commercial progress of lithium–sulfur batteries are still far from satisfactory due to the disconnection and huge gap between fundamental research and practical application. Therefore, it is highly necessary to revisit the scientific issues for the industrial applications of lithium–sulfur batteries. In this review, we focus on discussing the impact of design parameters (such as compaction density, sulfur loading, and electrolyte/sulfur ratio) on the electrochemical performance of lithium–sulfur batteries and corresponding inherent relationship and rules between them. We also propose the practical design rules of advanced sulfur electrodes. Moreover, safety hazard in respect of electrolyte, separator, and lithium metal anode is also illustrated in detail. With the target of paving the way for practical application of lithium–sulfur batteries, feasible solutions and strategies are brought up to address the aforementioned problems. Finally, we will discuss the current challenges and future research chance of lithium–sulfur batteries.
Biomass‐Derived Poly(Furfuryl Alcohol)–Protected Aluminum Anode for Lithium‐Ion Batteries
Authors: Ling Han Yeu , Su Zhong , Chen Hao , Hencz Luke , Zhang Miao , Tang Yongbing , Zhang Shanqing 
Published: December 2018

Aluminum is one of the promising alternative anode materials due to its high specific capacity. However, some critical problems seriously limit its practical applications, such as the low coulombic efficiency and poor cycle performance resulting from the huge volume change during cycling. Herein, a novel poly(furfuryl alcohol)/carbon black binder composite is coated on the surface of aluminum foil as a robust and conductive protective layer to maintain the integrity of the hybrid aluminum anode. The results show that 150 cycles under the preset cutoff capacity loading of 400 mA h g−1 are obtained and exhibit obvious advantages over a bare aluminum anode, which will crack after just 25 cycles. For full‐cell testing paired with a LiFePO4 cathode, the cell using the hybrid aluminum anode has a better capacity retention against the unprotected aluminum anode.
Verbal fluency in a national sample: Telephone administration methods
Authors: Marceaux Janice C. , Prosje Michelle A. , McClure Leslie A. , Kana Bhumika , Crowe Michael , Kissela Brett , Manly Jennifer , Howard George , Tam Joyce W. , Unverzagt Frederick W. , Wadley Virginia G. 
Published: December 2018

ObjectivesDescribe novel methods for ascertaining verbal fluency in a large national sample of adults, examine demographic factors influencing performance, and compare scores to studies using in‐person assessment.Methods/designParticipants were from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study, a national, population‐based, longitudinal study of stroke in adults aged 45 years and older. Letter and semantic fluency were gathered, using Letter “F” and Animal Naming, via a telephone‐based assessment with computer‐assisted scoring of digital recordings.ResultsInitial letter and semantic fluency scores were obtained on 18 505 and 18 072 participants, respectively. For both fluency tests, scores were normally distributed. Younger age and more years of education were associated with better performances (p < 0.0001). The mean and standard deviation for matched subgroups, based on age, gender, and education, were quite comparable with scores reported out of samples using an in‐person administration format. Telephone‐based assessment also allowed for a level of quality control not available via in‐person measurement.ConclusionsTelephone‐based assessment of verbal fluency and computer‐assisted scoring programs designed for this study facilitated large‐scale data acquisition, storage, and scoring of protocols. The resulting scores have similar characteristics to those obtained by traditional methods. These findings extend validation of cognitive assessment methods, using survey research staff and computer‐assisted technology for test administration.
Streamwater ages in nested, seasonally cold Canadian watersheds
Authors: Bansah Samuel , Ali Genevieve 
Published: December 2018

AbstractThe mean transit time (MTT) is an important descriptor of water storage and release dynamics in watersheds. Although MTT studies are numerous for many regions around the world, they are rare for prairie watersheds where seasonally cold or dry conditions require adequate methodological choices towards MTT estimation, especially regarding the handling of sparse data records and tracer selection. To examine the impact of such choices, we used timeseries of δ18O and δ2H from two contrasted years (2014 and 2015) and relied on two metrics and two modelling methods to infer MTTs in prairie watersheds. Our focus was on nested outlets with different drainage areas, geologies, and known run‐off generation mechanisms. The damping ratio and young water fraction (i.e., the fraction of streamflow with transit times lesser than 3 months) metrics, as well as the sine‐wave modelling and time‐based convolution modelling methods, were applied to year‐specific data. Results show that young water fractions and modelled MTT values were, respectively, larger and smaller in 2014, which was a wet year, compared with that in 2015. In 2014, most outlets had young water fractions larger than 0.5 and MTT values lesser than 6 months. The damping ratio, young water fraction, and sine‐wave modelling methods led to convergent conclusions about watershed water storage and release dynamics for some of the monitored sites. Contrasting results were, however, obtained when the same method was applied using δ2H instead of δ18O, due to differing evaporation fractionation, or when the time‐based convolution modelling method was used. Some methods also failed to provide any robust results during the dry year (i.e., 2015), highlighting the difficulty in inferring MTTs when data are sparse due to intermittent streamflow. This study therefore allowed the formulation of empirical recommendations for MTT estimation in prairie environments as a function of data availability and antecedent wetness conditions.
Inhibition of NLRP3 inflammasome attenuates spinal cord injury‐induced lung injury in mice
Authors: Jiang Wu , Li Maoqiang , He Fan , Zhu Liulong 
Published: December 2018

AbstractSpinal cord injury (SCI) is one kind of severe traumatic injury, resulting in systemic inflammatory response syndrome and secondary lung injury, which is an important pathological basis of respiratory complications. The nucleotide‐binding domain‐like receptor protein 3 (NLRP3) inflammasome is an important cytosolic protein complex in many inflammatory diseases. Hence, it is inescapable to explore the effect of inhibition of NLRP3 inflammasome by inhibitors in a mouse SCI model, which was conducted by using the method of 30‐G closing force aneurysm clipping at T6–T7 spinal segment for 1 min, followed by assessment of edema, histology, alveolar type II cell apoptosis, mitochondrial dysfunction, and neutrophil infiltration. In brief, our results showed that, NLRP3 inflammasome inhibitor BAY 11‐7082 or A438079 inhibited activation of NLRP3 inflammasome, alleviated mitochondrial dysfunction, the number of macrophage and neutrophil, thereby attenuating alveolar type II cell apoptosis, lung edema, and histological injury. Taken together, our data reveal that NLRP3 inflammasome inhibitor BAY 11‐7082 or A438079 attenuates the inflammatory response, reverses mitochondrial dysfunction, and subsequently alleviates secondary lung injury following SCI.