bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wind‐driven ocean dynamics impact on the contrasting sea‐ice trends around West Antarctica
Authors: Lee Sang‐Ki , Volkov Denis L. , Lopez Hosmay , Cheon Woo Geun , Gordon Arnold L. , Liu Yanyun , Wanninkhof Rik 
Published: March 2017

AbstractSince late 1978, Antarctic sea‐ice extent in the East Pacific has retreated persistently over the Amundsen and Bellingshausen Seas in warm seasons, but expanded over the Ross and Amundsen Seas in cold seasons, while almost opposite seasonal trends have occurred in the Atlantic over the Weddell Sea. By using a surface‐forced ocean and sea‐ice coupled model, we show that regional wind‐driven ocean dynamics played a key role in driving these trends. In the East Pacific, the strengthening Southern Hemisphere (SH) westerlies in the region enhanced the Ekman upwelling of warm upper Circumpolar Deep Water and increased the northward Ekman transport of cold Antarctic surface water. The associated surface ocean warming south of 68°S and the cooling north of 68°S directly contributed to the retreat of sea‐ice in warm seasons and the expansion in cold seasons, respectively. In the Atlantic, the poleward shifting SH westerlies in the region strengthened the northern branch of the Weddell Gyre, which in turn increased the meridional thermal gradient across it as constrained by the thermal wind balance. Ocean heat budget analysis further suggests that the strengthened northern branch of the Weddell Gyre acted as a barrier against the poleward ocean heat transport, and thus produced anomalous heat divergence within the Weddell Gyre and anomalous heat convergence north of the gyre. The associated cooling within the Weddell Gyre and the warming north of the gyre contributed to the expansion of sea‐ice in warm seasons and the retreat in cold seasons, respectively.
A statistical study on the subthermocline submesoscale eddies in the northwestern Pacific Ocean based on Argo data
Authors: Li Cheng , Zhang Zhiwei , Zhao Wei , Tian Jiwei 
Published: March 2017

AbstractIn this study, statistical characteristics and spatiotemporal variability of the cold‐core subthermocline eddies (STEs) discovered by Zhang et al. (2015) in the northwestern Pacific are investigated with 14 years of Argo temperature/salinity (T/S) data between 2002 and 2015. By applying an objective identification procedure to Argo T/S profiles, a total of 337 lens‐like STEs that trap cold and fresh homogeneous water are obtained. The STEs' cores are primarily located between 26.5 and 26.9
(300–800 m) and their shapes share a uniform Gaussian structure in vertical. Vertical and horizontal scale of the STEs is generally between 100 and 200 m and 5 and 15 km, respectively, suggesting that they are in the category of submesoscale processes. According to their different densities and seasonalities, the STEs are classified into upper and lower types with density interface of 26.7
. The number of upper‐type STEs is much larger in spring and summer than in autumn and winter while that of lower‐type ones show relatively uniform seasonal distributions. Spatially, the STEs are primarily distributed within the region between the Kuroshio Extension (KE) and subarctic front (SAF) in meridional and 140°E–155°E in zonal direction. Based on STEs' spatial distributions and vertical locations, we propose to name these STEs as KE intermediate‐layer eddies (Kiddies). Water property analysis suggests that the Kiddies most likely originated from the SAF region. For the upper‐type Kiddies, they are probably generated through subduction associated with mixed‐layer frontogenesis, which at least contribute to 0.25 Sv annual subduction rate for the layers 26.2–26.7
.
Equatorial Stokes drift and Rossby rip currents
Authors: Weber Jan Erik H. 
Published: March 2017

AbstractThe Stokes drift in long baroclinic equatorial Rossby waves is investigated theoretically by using eigenfunction expansions in the vertical. These waves are nondispersive and propagate westward along the equator. Particular attention is paid to the first baroclinic, first meridional Rossby wave mode which has been observed in the equatorial Pacific. It is demonstrated that the Stokes drift depends very much on the depth‐variation of the Brunt‐Väisälä frequency. Even more importantly, it is found that, for arbitrary stable stratification, the total zonal Stokes volume transport induced by the Rossby wave mode (1,1) is identically zero. The eastward drift due reflected wave energy in the form of internal equatorial Kelvin waves is also addressed. Due to the very long period of the incident Rossby wave mode (1,1), the reflected equatorial Kelvin wave must at least be a 2. mode component in the vertical. The corresponding Stokes drift only induces a minor change near the surface of the total westward drift velocity at the equator. The implication for the existence of compensating Rossby rip currents along the equator is discussed.
Periodicities of polar mesospheric clouds inferred from a meteorological analysis and forecast system
Authors: Stevens M. H. , Lieberman R. S. , Siskind D. E. , McCormack J. P. , Hervig M. E. , Englert C. R. 
Published: March 2017

AbstractThere is currently an ambiguity in what controls polar mesospheric cloud (PMC) periodicities near 83 km altitude. This is primarily because satellite and ground‐based data sets cannot resolve global mesospheric temperature variability over the diurnal cycle. To address this limitation, we employ a global meteorological analysis and forecast system that assimilates mesospheric satellite data with two significant advances. The first is that we use output at a more rapid one hourly cadence, allowing for a quantitative description of diurnal (24 h), semidiurnal (12 h), and terdiurnal oscillations. The second is that the output drives a simple PMC parameterization which depends only on the local temperature, pressure, and water vapor concentrations. Our study focuses on results from July 2009 in the Northern Hemisphere and January 2008 in the Southern Hemisphere. We find that the 24 h migrating temperature tide as well as the 12 h and 24 h nonmigrating tides dominate northern PMC oscillations whereas the 12 h and 24 h nonmigrating tides dominate southern oscillations. Monthly averaged amplitudes for each of these components are generally 2–6 K with the larger amplitudes at lower PMC latitudes (50°). The 2 day and 5 day planetary waves also contribute in both hemispheres, with monthly averaged amplitudes from 1 to 3 K although these amplitudes can be as high as 4–6 K on some days. Over length scales of ~1000 km and timescales of ~1 week, we find that local temperature oscillations adequately describe midlatitude PMC observations.
Continental‐scale variation in controls of summer CO2 in United States lakes
Authors: Lapierre Jean‐Francois , Seekell David A. , Filstrup Christopher T. , Collins Sarah M. , Emi Fergus C. , Soranno Patricia A. , Cheruvelil Kendra S. 
Published: March 2017

AbstractUnderstanding the broad‐scale response of lake CO2 dynamics to global change is challenging because the relative importance of different controls of surface water CO2 is not known across broad geographic extents. Using geostatistical analyses of 1080 lakes in the conterminous United States, we found that lake partial pressure of CO2 (pCO2) was controlled by different chemical and biological factors related to inputs and losses of CO2 along climate, topography, geomorphology, and land use gradients. Despite weak spatial patterns in pCO2 across the study extent, there were strong regional patterns in the pCO2 driver‐response relationships, i.e., in pCO2 “regulation.” Because relationships between lake CO2 and its predictors varied spatially, global models performed poorly in explaining the variability in CO2 for U.S. lakes. The geographically varying driver‐response relationships of lake pCO2 reflected major landscape gradients across the study extent and pointed to the importance of regional‐scale variation in pCO2 regulation. These results indicate a higher level of organization for these physically disconnected systems than previously thought and suggest that changes in climate and land use could induce shifts in the main pathways that determine the role of lakes as sources and sinks of atmospheric CO2.
Global satellite data highlights the diurnal asymmetry of the surface temperature response to deforestation
Authors: Schultz Natalie M. , Lawrence Peter J. , Lee Xuhui 
Published: March 2017

AbstractUncertainties remain about the spatial pattern and magnitude of the biophysical effects of deforestation. In particular, a diurnal asymmetry in the magnitude and sign of the surface temperature response to deforestation (ΔTS) has been observed, but the biophysical processes that contribute to day and nighttime ΔTS are not fully understood. In this study, we use a space‐for‐time approach with satellite and reanalysis data to investigate the biophysical processes that control the day and nighttime ΔTS. Additionally, we incorporate flux‐tower data to examine two hypotheses for nighttime forest warming relative to open lands: (1) that forests generate turbulence in the stable nocturnal boundary layer, which brings heat aloft down to the surface, and (2) that forests store more heat during the day and release it at night. Our results confirm a diurnal asymmetry in ΔTS. Over most regions of the world, deforestation results in daytime warming and nighttime cooling. The strongest daytime warming is in the tropics, where the average ΔTS is 4.4 ± 0.07 K. The strongest nighttime cooling is observed in the boreal zone, where open lands are cooler than forests by an average of 1.4 ± 0.04 K. Daytime patterns of ΔTS are explained by differences in the latent heat flux (ΔLE) and absorbed solar radiation (ΔKa). We find that nighttime ΔTS is related to the strength of the nocturnal temperature inversion, with stronger temperature inversions at high latitudes and weak inversions in the tropics. Forest turbulence at night combined with stored heat release drives nighttime ΔTS patterns.
Preferential sequestration of terrestrial organic matter in boreal lake sediments
Authors: Guillemette François , von Wachenfeldt Eddie , Kothawala Dolly N. , Bastviken David , Tranvik Lars J. 
Published: March 2017

AbstractThe molecular composition and origin has recently been demonstrated to play a critical role in the persistence of organic matter in lake water, but it is unclear to what degree chemical attributes and sources may also control settling and burial of organic matter in lake sediments. Here we compared the annual contribution of allochthonous and autochthonous sources to the organic matter settling in the water column and present in the sediments of 12 boreal lakes. We used the fluorescence properties and elemental composition of the organic matter to trace its origin and found a consistent pattern of increasing contribution of terrestrial compounds in the sediments as compared to the settling matter, with an annual average allochthony of ~87% and ~57%, respectively. Seasonal data revealed a predominance of in‐lake‐produced compounds sinking in the water column in summer. Yet only a slight concurrent decrease in the contribution of terrestrial C to lake sediments was observed during the same period, and sediment allochthony increased again to high levels in autumn. Our results reveal a preferential preservation of allochthonous matter in the sediments and highlight the role of lakes as sequesters of organic carbon primarily originating from the surrounding landscape.
Decadal‐scale changes in forest soil carbon and nitrogen storage are influenced by organic matter removal during timber harvest
Authors: Mushinski Ryan M. , Boutton Thomas W. , Scott D. Andrew 
Published: March 2017

AbstractThis study investigates whether different intensities of organic matter removal associated with timber harvest influence decadal‐scale storage of soil organic carbon (SOC) and total nitrogen (TN) in the top 1 m of mineral soil 18 years postharvest in a Pinus taeda L. forest in the Gulf Coastal Plain. We quantified forest harvest‐related changes in SOC, TN, microbial biomass carbon (MBC), and nitrogen (MBN) pools (0–100 cm) in unharvested control stands and in two organic matter removal treatment stands subjected to either (i) merchantable bole/stem‐only harvest or (ii) whole‐tree harvest + forest floor removal. In addition, δ13C of SOC and δ15N of TN were measured in mineral soil to provide insights regarding mechanisms that might explain changes in SOC and TN pool sizes. Soils were sampled seasonally for 1 year. Increasing organic matter removal intensity reduced SOC, TN, MBC, and MBN relative to the unharvested control. Furthermore, soils from whole‐tree harvest + forest floor removal stands had lower δ13C and higher δ15N values, suggesting that increasing organic matter removal may decrease heterotrophic activity as well as increase rates of N loss. Seasonal variabilities in SOC and TN were correlated to changes in forest biological properties such as root biomass and forest floor mass. These results indicate that more intensive harvest methods may lead to decade‐scale decreases in SOC and TN storage in surface and subsurface soils which could influence rates of biogeochemical processes, the availability of soil nutrients, and potential forest productivity.
Mechanism of seasonal eddy kinetic energy variability in the eastern equatorial Pacific Ocean
Authors: Wang Minyang , Du Yan , Qiu Bo , Cheng Xuhua , Luo Yiyong , Chen Xiao , Feng Ming 
Published: March 2017

AbstractEnhanced mesoscale eddy activities or tropical instability waves (TIWs) exist along the northern front of the cold tongue in the eastern equatorial Pacific Ocean. In this study, we investigate seasonal variability of eddy kinetic energy (EKE) over this region and its associated dynamic mechanism using a global, eddy‐resolving ocean general circulation model (OGCM) simulation, the equatorial mooring data, and satellite altimeter observations. The seasonal‐varying enhanced EKE signals are found to expand westward from 100°W in June to 180°W in December between 0°N and 6°N. This westward expansion in EKE is closely connected to the barotropically‐baroclinically unstable zonal flows that are in thermal‐wind balance with the seasonal‐varying thermocline trough along 4°N. By adopting an 1½‐layer reduced‐gravity model, we confirm that the seasonal perturbation of the thermocline trough is dominated by the anticyclonic wind stress curl forcing, which develops due to southerly winds along 4°N from June to December.
Respondent Burden, Reduction of
Authors: Tortora Robert 
Published: March 2017

AbstractRespondent burden is the effort, in terms of time and cost, required by respondents to provide answers to a survey or census. Burden is a multidimensional concept that includes length of an interview, frequency of being interviewed, the effort to retrieve the data asked for, and the stress encountered in providing the data. Thus, respondent burden has actual and perceived components and has the potential to introduce nonresponse and measurement error. This article presents a section on reducing respondent burden using good web questionnaire design practices and concludes with a discussion of the Consumer Expenditure Survey (CES), which has introduced several modes of data collection to reduce respondent burden as well as nonresponse and measurement error.
Robust Testing Procedures
Authors: Wilcox Rand R. 
Published: March 2017

Abstract
Robust testing procedures are hypothesis testing techniques that are relatively insensitive to violations of assumptions such as normality and homoscedasticity. Major advances on how to study and develop robust testing techniques have appeared during the past 50 years. The result has been a much better understanding of why conventional ANOVA and regression methods can be highly unsatisfactory in terms of both power and control over the type I error probability. There is now a vast collection of new methods that can provide a deeper, more accurate, and more nuanced understanding of data.
Synthetic Approach Towards the Synthesis of Antimalarial Gomphostenin
Authors: Swapnil Nipunge , Kumar Alleni Suman , Babu Nanubolu Jagadeesh , Yadav Jhillu Singh 
Published: March 2017

AbstractAn efficient and concise stereoselective synthesis towards the antimalarial (−)‐Gomphostenin, starting with the enantiomerically pure Wieland–Miescher ketone, is reported. The key transformations of the convergent synthesis involved a stereoselective reductive allylation, Palladium‐catalyzed Saegusa–Ito oxidation, Babler–Dauben oxidative rearrangement, and Wittig olefination reactions. The structure and absolute stereochemistry were determined by X‐ray analysis.
Ein achtkerniger metallosupramolekularer Würfel mit Spin‐Crossover‐Eigenschaften
Authors: Struch Niklas , Bannwarth Christoph , Ronson Tanya K. , Lorenz Yvonne , Mienert Bernd , Wagner Norbert , Engeser Marianne , Bill Eckhard , Puttreddy Rakesh , Rissanen Kari , Beck Johannes , Grimme Stefan , Nitschke Jonathan R. , Lützen Arne 
Published: March 2017

AbstractNach dem Ansatz der Subkomponenten‐Selbstorganisation lassen sich aus 5,10,15,20‐Tetrakis(4‐aminophenyl)porphyrin oder dessen Zink(II)‐Komplex, 1H‐4‐Imidazol‐carbaldehyd und Zink(II)‐ oder Eisen(II)‐Salzen O‐symmetrische Käfige mit einem abgeschlossenen Hohlraum von 1300 Å3 darstellen. Eisen(II)‐Salze lieferten Käfigverbindungen, die bei Raumtemperatur im High‐spin‐Zustand vorliegen und beim Abkühlen in den Low‐spin‐Zustand übergehen, während die Verwendung von Zink(II)‐Salzen die diamagnetischen Analoga liefert. Die Verbindungen wurden mit Synchrotron‐Einkristallröntgenbeugung, hochauflösender Massenspektrometrie, NMR‐, Mößbauer‐, IR‐ und UV‐Vis‐Spektroskopie charakterisiert. Die Struktur der Käfigverbindungen und ihre UV‐Vis‐Spektren wurden unabhängig durch DFT‐Rechnungen bestätigt. Ein besonderer Effekt ist die Stabilisierung des High‐spin‐Zustands durch Einschluss von C70 in den Käfigen. Im Fall des Wirt‐Gast‐Komplexes liegt die Übergangstemperatur T1/2 um 20 K tiefer als die des freien Wirts.
An Octanuclear Metallosupramolecular Cage Designed To Exhibit Spin‐Crossover Behavior
Authors: Struch Niklas , Bannwarth Christoph , Ronson Tanya K. , Lorenz Yvonne , Mienert Bernd , Wagner Norbert , Engeser Marianne , Bill Eckhard , Puttreddy Rakesh , Rissanen Kari , Beck Johannes , Grimme Stefan , Nitschke Jonathan R. , Lützen Arne 
Published: March 2017

AbstractBy employing the subcomponent self‐assembly approach utilizing 5,10,15,20‐tetrakis(4‐aminophenyl)porphyrin or its zinc(II) complex, 1H‐4‐imidazolecarbaldehyde, and either zinc(II) or iron(II) salts, we were able to prepare O‐symmetric cages having a confined volume of ca. 1300 Å3. The use of iron(II) salts yielded coordination cages in the high‐spin state at room temperature, manifesting spin‐crossover in solution at low temperatures, whereas corresponding zinc(II) salts led to the corresponding diamagnetic analogues. The new cages were characterized by synchrotron X‐ray crystallography, high‐resolution mass spectrometry, and NMR, Mössbauer, IR, and UV/Vis spectroscopy. The cage structures and UV/Vis spectra were independently confirmed by state‐of‐the‐art DFT calculations. A remarkably high‐spin‐stabilizing effect through encapsulation of C70 was observed. The spin‐transition temperature T1/2 is lowered by 20 K in the host–guest complex.
Citalopram Induces Reproductive Toxicity in Male Rats
Authors: Ilgin Sinem , Kilic Gozde , Baysal Merve , Kilic Volkan , Korkut Busra , Ucarcan Seyda , Atli Ozlem 
Published: March 2017

BackgroundCitalopram hydrobromide (CTL) has been shown to cause sexual dysfunction; however, its reproductive toxicity potential has not been sufficiently elucidated in men. Therefore, we aimed to clarify the toxic effects of CTL on the reproductive system of male rats.MethodsFor this purpose, CTL was administered at 5, 10, and 20 mg/kg/day to rats orally for 28 days. Sperm concentration, motility, and morphology were investigated using a computer‐assisted sperm analysis system, and sperm DNA damage was detected using a Comet assay. The testes were histopathologically examined. Serum follicle‐stimulating hormone, luteinizing hormone, and testosterone levels were measured and the oxidative status of testes was investigated.ResultsOur results showed that sperm concentration was reduced, and abnormal sperm morphology and sperm DNA damage were increased in CTL‐administered groups. Additionally, histopathological changes were observed in the testes of CTL‐administered rats. Luteinizing hormone levels were increased in CTL‐administered groups, while testosterone levels were increased in the 5 and 10 mg/kg CTL‐administered groups. Decreased glutathione signaled enhanced oxidative stress in the 10 and 20 mg/kg CTL‐administered groups.ConclusionThus, we concluded that CT induced testicular damage in male rats; this testicular damage was accompanied by oxidative stress and hormonal changes, which are considered as the important causes of reproductive disorders. Birth Defects Research 109:475–485, 2017. © 2017 Wiley Periodicals, Inc.
Foresight beats hindsight: The neural correlates underlying motor preparation in the pro‐/anti‐cue paradigm
Authors: Emmerling Franziska , Duecker Felix , de Graaf Tom A. , Schuhmann Teresa , Adam Jos J. , Sack Alexander T. 
Published: March 2017

AbstractBackgroundHuman motor behaviors are characterized by both, reactive and proactive mechanisms. Yet, studies investigating the neural correlates of motor behavior almost exclusively focused on reactive motor processes. Here, we employed the pro‐/anti‐cue motor preparation paradigm to systematically study proactive motor control in an imaging environment. In this paradigm, either pro‐ or anti‐cues are presented in a blocked design. Four fingers (two from each hand) are mapped onto four visual target locations. Visual targets require a speeded response by one corresponding finger, but, most importantly, they are preceded by visual cues that are congruent (“pro‐cue”), incongruent (“anti‐cue”), or neutral with respect to the responding hand. With short cue‐target intervals, congruence effects are based on automatic motor priming of the correct hand (in case of pro‐cues) or incorrect hand (in case of anti‐cues), generating, respectively, reaction time benefits or reaction time costs relative to the neutral‐cue. With longer cue‐target intervals, slower top‐down processes become effective, transforming early anti‐cue interference into late anti‐cue facilitation.MethodsWe adapted this paradigm to be compatible with neuroimaging, tested and validated it behaviorally—both inside and outside the imaging environment—and implemented it in a whole‐brain functional magnetic resonance imaging study.Results and ConclusionOur imaging results indicate that pro‐cues elicited much less neural activation than did anti‐cues, the latter recruiting well‐known cognitive top‐down networks related to attention, response inhibition, and error monitoring/signaling, thereby revealing high‐level influences on proactive motor processes.
Perioperative intravenous immunoglobulin treatment in a patient with severe acquired von Willebrand syndrome: case report and review of the literature
Authors: Jennes Eva , Guggenberger Dorothee , Zotz Rainer , Thompson Lora , Brümmendorf Tim H. , Koschmieder Steffen , Jost Edgar 
Published: March 2017

Key Clinical MessageAcquired von Willebrand syndrome may be related to plasma cell dyscrasia and can cause severe bleeding complications. Treatment, for example, with intravenous immunoglobulins may be indicated in selected cases. Physicians treating plasma cell dyscrasia have to be aware of bleeding complications in these patients, and clarification is necessary.