bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early Spring Phytoplankton Dynamics in the Western Antarctic Peninsula
Authors: Arrigo Kevin R. , van Dijken Gert L. , Alderkamp Anne‐Carlijn , Erickson Zachary K. , Lewis Kate M. , Lowry Kate E. , Joy‐Warren Hannah L. , Middag Rob , Nash‐Arrigo Janice E. , Selz Virginia , van de Poll Willem 
Published: November 2017

AbstractThe Palmer Long‐Term Ecological Research program has sampled waters of the western Antarctic Peninsula (wAP) annually each summer since 1990. However, information about the wAP prior to the peak of the phytoplankton bloom in January is sparse. Here we present results from a spring process cruise that sampled the wAP in the early stages of phytoplankton bloom development in 2014. Sea ice concentrations were high on the shelf relative to nonshelf waters, especially toward the south. Macronutrients were high and nonlimiting to phytoplankton growth in both shelf and nonshelf waters, while dissolved iron concentrations were high only on the shelf. Phytoplankton were in good physiological condition throughout the wAP, although biomass on the shelf was uniformly low, presumably because of heavy sea ice cover. In contrast, an early stage phytoplankton bloom was observed beneath variable sea ice cover just seaward of the shelf break. Chlorophyll a concentrations in the bloom reached 2 mg m−3 within a 100–150 km band between the SBACC and SACCF. The location of the bloom appeared to be controlled by a balance between enhanced vertical mixing at the position of the two fronts and increased stratification due to melting sea ice between them. Unlike summer, when diatoms overwhelmingly dominate the phytoplankton population of the wAP, the haptophyte Phaeocystis antarctica dominated in spring, although diatoms were common. These results suggest that factors controlling phytoplankton abundance and composition change seasonally and may differentially affect phytoplankton populations as environmental conditions within the wAP region continue to change.
Spume Drops: Their Potential Role in Air‐Sea Gas Exchange
Authors: Monahan Edward C. , Staniec Allison , Vlahos Penny 
Published: November 2017

AbstractAfter summarizing the time scales defining the change of the physical properties of spume and other droplets cast up from the sea surface, the time scales governing drop‐atmosphere gas exchange are compared. Following a broad review of the spume drop production functions described in the literature, a subset of these functions is selected via objective criteria, to represent typical, upper bound, and lower bound production functions. Three complementary mechanisms driving spume‐atmosphere gas exchange are described, and one is then used to estimate the relative importance, over a broad range of wind speeds, of this spume drop mechanism compared to the conventional, diffusional, sea surface mechanism in air‐sea gas exchange. While remaining uncertainties in the wind dependence of the spume drop production flux, and in the immediate sea surface gas flux, preclude a definitive conclusion, the findings of this study strongly suggest that, at high wind speeds (>20 m s−1 for dimethyl sulfide and >30 m s−1 for gases such a carbon dioxide), spume drops do make a significant contribution to air‐sea gas exchange.
Spatial Variation of Diapycnal Diffusivity Estimated From Seismic Imaging of Internal Wave Field, Gulf of Mexico
Authors: Dickinson Alex , White N. J. , Caulfield C. P. 
Published: November 2017

AbstractBright reflections are observed within the upper 1,000 m of the water column along a seismic reflection profile that traverses the northern margin of the Gulf of Mexico. Independent hydrographic calibration demonstrates that these reflections are primarily caused by temperature changes associated with different water masses that are entrained into the Gulf along the Loop Current. The internal wave field is analyzed by automatically tracking 1,171 reflections, each of which is greater than 2 km in length. Power spectra of the horizontal gradient of isopycnal displacement,
, are calculated from these tracked reflections. At low horizontal wave numbers (
cpm),
, in agreement with hydrographic observations of the internal wave field. The turbulent spectral subrange is rarely observed. Diapycnal diffusivity, K, is estimated from the observed internal wave spectral subrange of each tracked reflection using a fine‐scale parametrization of turbulent mixing. Calculated values of K vary between
and
m2 s−1 with a mean value of
m2 s−1. The spatial distribution of turbulent mixing shows that
m2 s−1 away from the shelf edge in the upper 300 m where stratification is strong. Mixing is enhanced by up to 4 orders of magnitude adjacent to the shoaling bathymetry of the continental slope. This overall pattern matches that determined by analyzing nearby suites of CTD casts. However, the range of values recovered by spectral analysis of the seismic image is greater as a consequence of significantly better horizontal resolution.
Shallow Aquifer Vulnerability From Subsurface Fluid Injection at a Proposed Shale Gas Hydraulic Fracturing Site
Authors: Wilson M. P. , Worrall F. , Davies R. J. , Hart A. 
Published: November 2017

AbstractGroundwater flow resulting from a proposed hydraulic fracturing (fracking) operation was numerically modeled using 91 scenarios. Scenarios were chosen to be a combination of hydrogeological factors that a priori would control the long‐term migration of fracking fluids to the shallow subsurface. These factors were induced fracture extent, cross‐basin groundwater flow, deep low hydraulic conductivity strata, deep high hydraulic conductivity strata, fault hydraulic conductivity, and overpressure. The study considered the Bowland Basin, northwest England, with fracking of the Bowland Shale at ∼2,000 m depth and the shallow aquifer being the Sherwood Sandstone at ∼300–500 m depth. Of the 91 scenarios, 73 scenarios resulted in tracked particles not reaching the shallow aquifer within 10,000 years and 18 resulted in travel times less than 10,000 years. Four factors proved to have a statistically significant impact on reducing travel time to the aquifer: increased induced fracture extent, absence of deep high hydraulic conductivity strata, relatively low fault hydraulic conductivity, and magnitude of overpressure. Modeling suggests that high hydraulic conductivity formations can be more effective barriers to vertical flow than low hydraulic conductivity formations. Furthermore, low hydraulic conductivity faults can result in subsurface pressure compartmentalization, reducing horizontal groundwater flow, and encouraging vertical fluid migration. The modeled worst‐case scenario, using unlikely geology and induced fracture lengths, maximum values for strata hydraulic conductivity and with conservative tracer behavior had a particle travel time of 130 years to the base of the shallow aquifer. This study has identified hydrogeological factors which lead to aquifer vulnerability from shale exploitation.
Evaluation of clinically applied treatment beams with respect to bunker shielding parameters for a Cyberknife M6
Authors: Henzen Dominik , Schmidhalter Daniel , Zanella Claudia Christina , Volken Werner , Mackeprang Paul‐Henry , Malthaner Marco , Fix Michael Karl , Manser Peter 
Published: November 2017

AbstractCompared to a conventional linear accelerator, the Cyberknife (CK) is a unique system with respect to radiation protection shielding and the variety and number of non‐coplanar beams are two key components regarding this aspect. In this work, a framework to assess the direction distribution and modulation factor (MF) of clinically applied treatment beams of a CyberKnife M6 is developed. Database filtering options allow studying the influence of different parameters such as collimator types, treatment sites or different bunker sizes. A distribution of monitor units (MU) is generated by projecting treatment beams onto the walls, floor and ceiling of the CyberKnife bunker. This distribution is found to be highly heterogeneous and depending, among other parameters, on the bunker size. For our bunker design, 10%–13% of the MUs are delivered to the right and left wall, each. The floor receives more than 64% of the applied MUs, while the wall behind the patient's head is not hit by primary treatment beams. Between 0% and 5% of the total MUs are delivered to the wall at the patient's feet. This number highly depends on the treatment site, e.g., for extracranial patients no beams hit that wall. Collimator choice was found to have minor influence on the distribution of MUs. On the other hand, the MF depends on the collimator type as well as on the treatment site. The MFs (delivered MU/prescribed dose) for all treatments, all MLC treatments, cranial and extracranial treatments are 8.3, 6.4, 7.7, and 9.9 MU/cGy, respectively. The developed framework allows assessing and monitoring important parameters regarding radiation protection of a CK‐M6 using the actually applied treatment beams. Furthermore, it enables evaluating different clinical and constructional situations using the filtering options.
Arthritis After Cancer Immunotherapy: Symptom Duration and Treatment Response
Authors: Smith Melanie H. , Bass Anne R. 
Published: November 2017

ObjectiveMusculoskeletal manifestations of immune‐related adverse events (irAEs) after checkpoint inhibitor immunotherapy for cancer remain incompletely characterized and poorly understood. A recently published case series suggested that immunotherapy‐induced arthritis is an aggressive process requiring high‐dose corticosteroids.MethodsThis was a retrospective chart review of all patients with musculoskeletal irAEs first seen by one of the authors between 2014 and 2016. All patients had been treated for a malignancy with immune checkpoint inhibitors targeting PD‐1 (nivolumab, pembrolizumab), PD‐L1 (durvalumab), and/or CTLA‐4 (ipilimumab, tremelimumab) at Memorial Sloan Kettering Cancer Center.ResultsWe identified 10 patients with a mean ± SD age of 63.2 ± 9.7 years. Seven were treated with a combination of checkpoint inhibitors and 3 with nivolumab monotherapy. Four patients developed inflammatory polyarthritis, 4 oligoarthritis, and 2 tenosynovitis. Six were antinuclear antibody positive and 2 had anti–cyclic citrullinated peptide antibodies. Mean ± SD time from the first dose of immunotherapy until joint involvement was 6.3 ± 4.3 months. All 10 patients were treated with systemic corticosteroids, but 6 of 10 required ≤20 mg per day of prednisone. Five patients received steroid‐sparing agents. Mean ± SD time until resolution of joint symptoms after the last dose of immunotherapy was 9.2 ± 6.1 months.ConclusionMusculoskeletal irAEs can manifest as a rheumatoid arthritis–like polyarthritis, oligoarthritis, tenosynovitis, or polymyalgia rheumatica. Musculoskeletal symptoms can last more than a year, but they can generally be managed with low to moderate doses of corticosteroids.
Enhancing the Quantum Anomalous Hall Effect by Magnetic Codoping in a Topological Insulator
Authors: Ou Yunbo , Liu Chang , Jiang Gaoyuan , Feng Yang , Zhao Dongyang , Wu Weixiong , Wang Xiao‐Xiao , Li Wei , Song Canli , Wang Li‐Li , Wang Wenbo , Wu Weida , Wang Yayu , He Ke , Ma Xu‐Cun , Xue Qi‐Kun 
Published: November 2017

AbstractThe quantum anomalous Hall (QAH) effect, which has been realized in magnetic topological insulators (TIs), is the key to applications of dissipationless quantum Hall edge states in electronic devices. However, investigations and utilizations of the QAH effect are limited by the ultralow temperatures needed to reach full quantization—usually below 100 mK in either Cr‐ or V‐doped (Bi,Sb)2Te3 of the two experimentally confirmed QAH materials. Here it is shown that by codoping Cr and V magnetic elements in (Bi,Sb)2Te3 TI, the temperature of the QAH effect can be significantly increased such that full quantization is achieved at 300 mK, and zero‐field Hall resistance of 0.97 h/e2 is observed at 1.5 K. A systematic transport study of the codoped (Bi,Sb)2Te3 films with varied Cr/V ratios reveals that magnetic codoping improves the homogeneity of ferromagnetism and modulates the surface band structure. This work demonstrates magnetic codoping to be an effective strategy for achieving high‐temperature QAH effect in TIs.
An Ideal Molecular Sieve for Acetylene Removal from Ethylene with Record Selectivity and Productivity
Authors: Li Bin , Cui Xili , O'Nolan Daniel , Wen Hui‐Min , Jiang Mengdie , Krishna Rajamani , Wu Hui , Lin Rui‐Biao , Chen Yu‐Sheng , Yuan Daqiang , Xing Huabin , Zhou Wei , Ren Qilong , Qian Guodong , Zaworotko Michael J. , Chen Banglin 
Published: November 2017

AbstractRealization of ideal molecular sieves, in which the larger gas molecules are completely blocked without sacrificing high adsorption capacities of the preferred smaller gas molecules, can significantly reduce energy costs for gas separation and purification and thus facilitate a possible technological transformation from the traditional energy‐intensive cryogenic distillation to the energy‐efficient, adsorbent‐based separation and purification in the future. Although extensive research endeavors are pursued to target ideal molecular sieves among diverse porous materials, over the past several decades, ideal molecular sieves for the separation and purification of light hydrocarbons are rarely realized. Herein, an ideal porous material, SIFSIX‐14‐Cu‐i (also termed as UTSA‐200), is reported with ultrafine tuning of pore size (3.4 Å) to effectively block ethylene (C2H4) molecules but to take up a record‐high amount of acetylene (C2H2, 58 cm3 cm−3 under 0.01 bar and 298 K). The material therefore sets up new benchmarks for both the adsorption capacity and selectivity, and thus provides a record purification capacity for the removal of trace C2H2 from C2H4 with 1.18 mmol g−1 C2H2 uptake capacity from a 1/99 C2H2/C2H4 mixture to produce 99.9999% pure C2H4 (much higher than the acceptable purity of 99.996% for polymer‐grade C2H4), as demonstrated by experimental breakthrough curves.
Copper Catalysis for Nicotinate Synthesis through β‐Alkenylation/Cyclization of Saturated Ketones with β‐Enamino Esters
Authors: Ling Fei , Xiao Lian , Fang Lu , Lv Yaping , Zhong Weihui 
Published: November 2017

AbstractThe first example of a Cu‐catalyzed and 4‐OH‐TEMPO mediated intermolecular [3+3] annulation of saturated ketones with β‐enamino esters is reported herein, which was successfully used for the synthesis of versatile nicotinates through sequential β‐C(sp3)‐H bond alkenylation, enamine‐carbonyl condensation and aromatization. This protocol tolerates a variety of functional groups, thereby providing a practical and efficient method for the fabrication of 5H‐chromeno[4,3‐b]pyridin‐5‐one skeletons.magnified image
Aqueous‐Containing Precursor Solutions for Efficient Perovskite Solar Cells
Authors: Liu Dianyi , Traverse Christopher J. , Chen Pei , Elinski Mark , Yang Chenchen , Wang Lili , Young Margaret , Lunt Richard R. 
Published: November 2017

AbstractPerovskite semiconductors have emerged as competitive candidates for photovoltaic applications due to their exceptional optoelectronic properties. However, the impact of moisture instability on perovskite films is still a key challenge for perovskite devices. While substantial effort is focused on preventing moisture interaction during the fabrication process, it is demonstrated that low moisture sensitivity, enhanced crystallization, and high performance can actually be achieved by exposure to high water content (up to 25 vol%) during fabrication with an aqueous‐containing perovskite precursor. The perovskite solar cells fabricated by this aqueous method show good reproducibility of high efficiency with average power conversion efficiency (PCE) of 18.7% and champion PCE of 20.1% under solar simulation. This study shows that water–perovskite interactions do not necessarily negatively impact the perovskite film preparation process even at the highest efficiencies and that exposure to high contents of water can actually enable humidity tolerance during fabrication in air.
Market power in the German dairy value chain
Authors: Grau Aaron , Hockmann Heinrich 
Published: November 2017

AbstractIn this paper, the NEIO approach is extended to allow for oligopsony power in successive markets of a value chain. Two price equations are deduced from simultaneous partial equilibria of the endogenous variables and are embedded in a VECM to account for a long‐run cointegration relationship. The model is estimated via the Kalman–Filter to allow for time variation in the long‐run parameters, and a dynamic factor model used to extract a common factor from the time‐variant coefficients. The results are then used to calculate the industry average input conjectural elasticities. The framework is applied to German dairy value chain data over the time period of January 2000 to March 2011. The results indicate almost perfect competition in the raw milk market and imperfect competition in the dairy output market, which is however far from monopsony. [EconLit citations: L13, D43, C32, Q13].
A Molecular Barium Hydrido Complex Stabilized by a Super‐Bulky Hydrotris(pyrazolyl)borate Ligand
Authors: Shi Xianghui , Hou Cuiping , Zhou Chulu , Song Yanyao , Cheng Jianhua 
Published: November 2017

AbstractHydrogenolysis of the scorpionate‐supported barium alkyl complex (TpAd,iPr)Ba[CH(SiMe3)2](THF) (TpAd,iPr=hydrotris(3‐adamantyl‐5‐isopropyl‐pyrazolyl)borate) afforded the dinuclear barium hydrido complex [(TpAd,iPr)Ba(μ‐H)]2 (2), which was characterized by NMR spectroscopy and single‐crystal X‐ray analysis. Exposure of 2 with 1 atm of CO resulted in a reductive coupling process to form the cis‐ethendiolate dianion (3). Reaction of 2 with one equivalent of PhC≡C−C≡CPh gave barium 1,4‐diphenyl‐2‐butyne‐1,4‐diyl complex {[(TpAd,iPr)Ba]2(PhCH−C≡C−CHPh) (4).
Site‐Selective O‐Arylation of Glycosides
Authors: Shang Weidong , Mou Ze‐Dong , Tang Hua , Zhang Xia , Liu Jie , Fu Zhengyan , Niu Dawen 
Published: November 2017

AbstractDirect and site‐selective O‐arylation of carbohydrates has been a challenge in synthesis. Herein we report a method based on copper‐catalyzed O‐arylation to address this challenge. Proper choice of the ancillary ligand on copper is critical for the efficiency and site selectivity of this transformation. This method features mild conditions, tolerates various functional groups, and demonstrates broad substrate scope.
Living Ab Initio Emulsion Polymerization of Methyl Methacrylate in Water Using a Water‐Soluble Organotellurium Chain Transfer Agent under Thermal and Photochemical Conditions
Authors: Fan Weijia , Tosaka Masatoshi , Yamago Shigeru , Cunningham Michael F. 
Published: November 2017

AbstractAb initio emulsion polymerization of methyl methacrylate (MMA) using a water‐soluble organotellurium chain transfer agent in the presence of the surfactant Brij 98 in water is reported. Polymerization proceeded under both thermal and visible light‐irradiation conditions, giving poly(methyl methacrylate) (PMMA) with controlled molecular weight and low dispersity (Đ<1.5). Despite the formation of an opaque latex, the photoactivation of the organotellurium dormant species took place efficiently, as demonstrated by the quantitative monomer conversion and temporal control. Control of polymer particle size (PDI<0.030) was also achieved using a semi‐batch monomer addition process. The PMMA polymer in the particles retained high end‐group fidelity and was successfully used for the synthesis of block copolymers.
The Divergent Dimerization Behavior of N‐Substituted Dicyanomethyl Radicals: Dynamically Stabilized versus Stable Radicals
Authors: Okino Kohei , Hira Shota , Inoue Yuki , Sakamaki Daisuke , Seki Shu 
Published: November 2017

AbstractHerein, we demonstrate that the dimerization behavior of amine‐substituted dicyanomethyl radicals can be switched from σ‐ to π‐dimerization simply by varying the electron‐donating substituents. For dicyanomethyl radicals with a 4,4′‐ditolylamine (DT.) or a phenothiazine (PT.) substituent, the monomeric radical form and the corresponding dimer connected by a reversible C−C bond (σ‐dimer) are in equilibrium in solution. On the other hand, the radical with the julolidine skeleton (JD.) does not undergo σ‐dimerization and was isolated as a stable radical in spite of the absence of bulky protecting groups. X‐ray single‐crystal analysis revealed that JD. forms the π‐dimer in the crystalline state, and variable‐temperature spectroscopy showed that JD. is in equilibrium with the π‐dimer in toluene solution. DFT calculations point to the importance of electrostatic interactions as a driving force for the π‐dimerization of JD. because of its polarized structure.
A novel ultra‐low energy reverse osmosis membrane modified by chitosan with glutaraldehyde crosslinking
Authors: Mehta Bhargav B. , Joshi Rutvik N. , Raval Hiren D. 
Published: November 2017

ABSTRACTThe energy consumption of reverse osmosis (RO) has declined significantly since inception and to further decrease the energy consumption is a challenging task. The present article demonstrates the novel method to increase the membrane productivity and reduce energy consumption of desalination. Thin film composite RO (TFC RO) membrane was subjected to 2000 mg/L sodium hypochlorite for 1 h followed by varying concentrations of chitosan and glutaraldehyde for 1 h each to make a hydrophilic supra‐molecular assembly of linear polysaccharide over the polyamide layer. RO membrane exposed to 1000 mg/L chitosan and glutaraldehyde each reported 180% increase in water‐flux with about 2.7% increase in divalent ion rejection as compared to virgin TFC RO membrane. The superior performance of the membrane was explained by increased hydrophilicity as shown by decline in contact angle from 46.37° to 29.87°, increase in surface area ratio from atomic force microscope image analysis, and modification in chemical structure of polyamide from attenuated total reflectance Fourier transform infrared spectroscopy. It was further investigated that curing of glutaraldehyde treated membrane resulted in decreased water‐flux because of increase in crosslink density. Thus, an ultra‐low energy RO process can be developed based on polyamide–chitosan–glutaraldehyde membrane. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45971.
Utility of Cremophor RH 40 as a micellar improvement for spectrofluorimetric estimation of sorafenib in pure form, commercial preparation, and human plasma
Authors: Zidan Dalia W. , Elmasry Manal S. , Hassan Wafaa S. , Shalaby Abdalla A. 
Published: November 2017

AbstractAn easy, quick, simple and accurate spectrofluorimetric method was recognized and validated for evaluation of sorafenib (SOR) in pure form and biologically in plasma. Cremophor RH 40 (Cr RH 40) used for enhancing the fluorescence activity of SOR in phosphate buffer (pH 7). Cr RH 40 improved the native fluorescence of SOR remarkably in water. The fluorescence spectrum of SOR was observed at 405 nm after excitation at 265 nm. The linearity appeared to be in the range of 5 to 600 ng ml−1 for pure and from 9 to 500 ng ml−1 for plasma using the protein precipitation (ppt) method while from 10 to 500 ng ml−1 for plasma using liquid–liquid extraction method. The precisions and the accuracy of the estimated method gave satisfactory results. The recommended method was effectively applied for determination of SOR in human plasma with high recovery values. The results of some compounds that are possibly found in plasma were studied. The proposed method was also focused on real volunteers and a drug dissolution test.