bluuebunny/crossref_metadata_2025_split huggingface dataset:
Climatic controls on the interannual to decadal variability in Saudi Arabian dust activity: Toward the development of a seasonal dust prediction model
Authors: Yu Yan , Notaro Michael , Liu Zhengyu , Wang Fuyao , Alkolibi Fahad , Fadda Eyad , Bakhrjy Fawzieh 
Published: February 2015

AbstractThe observed climatic controls on springtime and summertime Saudi Arabian dust activities during 1975–2012 are analyzed, leading to development of a seasonal dust prediction model. According to empirical orthogonal function analysis, dust storm frequency exhibits a dominantly homogeneous pattern across Saudi Arabia, with distinct interannual and decadal variability. The previously identified positive trend in remotely sensed aerosol optical depth since 2000 is shown to be a segment of the decadal oscillation in dust activity, according to long‐duration station record. Regression and correlation analyses reveal that the interannual variability in Saudi Arabian dust storm frequency is regulated by springtime rainfall across the Arabian Peninsula and summertime Shamal wind intensity. The key drivers of Saudi Arabian dust storm variability are identified. Winter‐to‐spring La Niña enhances subsequent spring dust activity by decreasing rainfall across the country's primary dust source region, the Rub' al Khali Desert. A relatively cool tropical Indian Ocean favors frequent summer dust storms by producing an anomalously anticyclonic circulation over the central Arabian Peninsula, which enhances the Shamal wind. Decadal variability in Saudi Arabian dust storm frequency is associated with North African rainfall and Sahel vegetation, which regulate African dust emissions and transport to Saudi Arabia. Mediterranean sea surface temperatures (SSTs) also regulate decadal dust variability, likely through their influence on Sahel rainfall and Shamal intensity. Using antecedent‐accumulated rainfall over the Arabian Peninsula and North Africa, and Mediterranean SSTs, as low‐frequency predictors, and tropical eastern Pacific and tropical Indian Ocean SSTs as high‐frequency predictors, Saudi Arabia's seasonal dust activity is well predicted.
On funneling of tidal channels
Authors: Lanzoni S. , D'Alpaos A. 
Published: February 2015

AbstractTidal channels dissect the tidal landscape and exert a crucial control on the morphodynamic evolution of these landscapes. Improving our understanding of channel equilibrium morphology is therefore an important issue for both theoretical and practical reasons. We analyze the case of a tidal channel dissecting a relatively short, unvegetated tidal flat characterized by microtidal conditions and a negligible external sediment supply. The three‐dimensional equilibrium configuration of the channel is determined on the basis of a hydrodynamic model, describing the cross‐sectional distribution of the longitudinal bed shear stresses, coupled with a morphodynamic model retaining the description of the main physical processes shaping the channel and the adjacent intertidal platform. Both channel bed and width are allowed to adapt to the flow field so that an equilibrium altimetric and planimetric configuration is eventually obtained, when erosion becomes negligibly small, and asymptotically constant elevations are reached everywhere within the domain. Model results reproduce several observed channel characteristics of geomorphic relevance, such as the relationship between channel cross‐sectional area and the flowing tidal prism, the scaling of the width‐to‐depth ratio with channel width, and the longitudinal distributions of bed elevations and channel widths. In analogy with empirical evidence from estuaries, tidal channel funneling is usually assumed to be described by an exponential trend. Our theoretical analyses, modeling results, and observational evidence suggest that a linear relationship also provides a good approximation to describe longitudinal variations in channel width for short tidal channels. Longitudinal bed profiles characterized by a strong planform funneling tend to attain an upward concavity, whereas a low degree of convergence implies an almost linear profile. Finally, the model allows one to analyze the influence of environmental conditions (sediment characteristics, basin size, tidal amplitude, etc.) on the geomorphological features of tidal channels (equilibrium cross‐sectional area and bottom profile, width‐to‐depth ratios, and planform shape). Wider and deeper channels develop as the width of the domain increases, as the tidal amplitude increases, or as the mean platform elevation decreases. Conversely, narrower and shallower channels result from an increase in the critical shear stress for erosion or a decrease in the flow conductance. We thus believe that this model provides a useful tool for quantitative analyses of long‐term morphodynamics of tidal landscapes.
Stochastic assessment of climate impacts on hydrology and geomorphology of semiarid headwater basins using a physically based model
Authors: Francipane A. , Fatichi S. , Ivanov V. Y. , Noto L. V. 
Published: February 2015

AbstractHydrologic and geomorphic responses of watersheds to changes in climate are difficult to assess due to projection uncertainties and nonlinearity of the processes that are involved. Yet such assessments are increasingly needed and call for mechanistic approaches within a probabilistic framework. This study employs an integrated hydrology‐geomorphology model, the Triangulated Irregular Network‐based Real‐time Integrated Basin Simulator (tRIBS)‐Erosion, to analyze runoff and erosion sensitivity of seven semiarid headwater basins to projected climate conditions. The Advanced Weather Generator is used to produce two climate ensembles representative of the historic and future climate conditions for the Walnut Gulch Experimental Watershed located in the southwest U.S. The former ensemble incorporates the stochastic variability of the observed climate, while the latter includes the stochastic variability and the uncertainty of multimodel climate change projections. The ensembles are used as forcing for tRIBS‐Erosion that simulates runoff and sediment basin responses leading to probabilistic inferences of future changes. The results show that annual precipitation for the area is generally expected to decrease in the future, with lower hourly intensities and similar daily rates. The smaller hourly rainfall generally results in lower mean annual runoff. However, a non‐negligible probability of runoff increase in the future is identified, resulting from stochastic combinations of years with low and high runoff. On average, the magnitudes of mean and extreme events of sediment yield are expected to decrease with a very high probability. Importantly, the projected variability of annual sediment transport for the future conditions is comparable to that for the historic conditions, despite the fact that the former account for a much wider range of possible climate “alternatives.” This result demonstrates that the historic natural climate variability of sediment yield is already so high, that it is comparable to the variability for a projected and highly uncertain future. Additionally, changes in the scaling relationship between specific sediment yield/runoff and drainage basin area are detected.
Modeling flow and sediment transport dynamics in the lowermost Mississippi River, Louisiana, USA, with an upstream alluvial‐bedrock transition and a downstream bedrock‐alluvial transition: Implications for land building using engineered diversions
Authors: Viparelli Enrica , Nittrouer Jeffrey A. , Parker Gary 
Published: February 2015

AbstractThe lowermost Mississippi River, defined herein as the river segment downstream of the Old River Control Structure and hydrodynamically influenced by the Gulf of Mexico, extends for approximately 500 km. This segment includes a bedrock (or more precisely, mixed bedrock‐alluvial) reach that is bounded by an upstream alluvial‐bedrock transition and a downstream bedrock‐alluvial transition. Here we present a one‐dimensional mathematical formulation for the long‐term evolution of lowland rivers that is able to reproduce the morphodynamics of both the alluvial‐bedrock and the bedrock‐alluvial transitions. Model results show that the magnitude of the alluvial equilibrium bed slope relative to the bedrock surface slope and the depth of bedrock surface relative to the water surface base level strongly influence the mobile bed equilibrium of low‐sloping river channels. Using data from the lowermost Mississippi River, the model is zeroed and validated at field scale by comparing the numerical results with field measurements. The model is then applied to predict the influence on the stability of channel bed elevation in response to delta restoration projects. In particular, the response of the river bed to the implementation of two examples of land‐building diversions to extract water and sediment from the main channel is studied. In this regard, our model results show that engineered land‐building diversions along the lowermost Mississippi River are capable of producing equilibrated bed profiles with only modest shoaling or erosion, and therefore, such diversions are a sustainable strategy for mitigating land loss within the Mississippi River Delta.
Intermediate‐depth icequakes and harmonic tremor in an Alpine glacier (Glacier d'Argentière, France): Evidence for hydraulic fracturing?
Authors: Helmstetter Agnès , Moreau Luc , Nicolas Barbara , Comon Pierre , Gay Michel 
Published: February 2015

AbstractWe detected several thousand deep englacial icequakes on Glacier d'Argentière (Mont‐Blanc massif) between 30 March and 3 May 2012. These events have been classified in eight clusters. Inside each cluster, the waveforms are similar for P waves and S waves, although the time delay between the P waves and the S waves vary by up to 0.03 s, indicating an extended source area. Although these events were recorded by a single accelerometer, they were roughly located using a polarization analysis. The deepest events were located at a depth of 130 m, 60 m above the ice/bed interface. The clusters are separated in space. The largest cluster extends over about 100 m. For this cluster, the strike of the rupture plane is nearly parallel to the direction of the open crevasses, and the dip angle is 56°. Deep icequakes occur in bursts of activity that last for a few hours and are separated by quiet periods. Many events occurred on 28 and 29 April 2012, during the warmest days, when snowmelting was likely important. The distributions of interevent times and peak amplitudes obey power laws as also observed for earthquakes, but with larger exponents. The polarity of the P waves for all of the events is consistent with tensile faulting. Finally, between 25 April and 3 May, we observed a gliding harmonic tremor with a fundamental resonance frequency that varied between 30 Hz and 38 Hz, with additional higher‐frequency harmonics. During this time we also observed shallow hybrid events with high‐frequency onsets and a monochromatic coda. These events might be produced by the propagation of fractures and the subsequent flow of water into the fracture. The strongest resonance was observed just after a strong burst of deep icequakes and during an unusually warm period when the snow height decreased by 60 cm in 1 week. The resonance frequency shows a succession of several sharp decreases and phases of progressive increases. One of the strongest negative steps of the resonance frequency on 28 April coincides with a burst of deep icequakes. These events appear to be associated with the propagation of fractures, which can explain the decrease in the resonance frequency. Finally, we observed an acceleration of glacier flow on 29 April, suggesting that meltwater had reached the ice/bed interface. These observations suggest that deep icequakes are due to hydraulic fracturing and that they can be used to track fluid flow inside glaciers.
Inference of sex‐specific expansion patterns in human populations from Y‐chromosome polymorphism
Authors: Aimé Carla , Heyer Evelyne , Austerlitz Frédéric 
Published: February 2015

ABSTRACTStudying the current distribution of genetic diversity in humans has important implications for our understanding of the history of our species. We analyzed a set of linked STR and SNP loci from the paternally inherited Y chromosome to infer the past demography of 55 African and Eurasian populations, using both the parametric and nonparametric coalescent‐based methods implemented in the BEAST application. We inferred expansion events in most sedentary farmer populations, while we found constant effective population sizes for both nomadic hunter‐gatherers and seminomadic herders. Our results differed, on several aspects, from previous results on mtDNA and autosomal markers. First, we found more recent expansion patterns in Eurasia than in Africa. This discrepancy, substantially stronger than the ones found with the other kind of markers, may result from a lower effective population size for men, which might have made male‐transmitted markers more sensitive to the out‐of‐Africa bottleneck. Second, we found expansion signals only for sedentary farmers but not for nomadic herders in Central Asia, while these signals were found for both kind of populations in this area when using mtDNA or autosomal markers. Expansion signals in this area may result from spatial expansion processes and may have been erased for the Y chromosome among the herders because of restricted male gene flow. Am J Phys Anthropol 157:217–225, 2015. © 2015 Wiley Periodicals, Inc.
Hydrolytic degradation and crystallization behavior of linear 2‐armed and star‐shaped 4‐armed poly(l‐lactide)s: Effects of branching architecture and crystallinity
Authors: Tsuji Hideto , Hayashi Toshiki 
Published: February 2015

ABSTRACT“Linear” aliphatic polyesters composed of two poly(l‐lactide) arms attached to 1,3‐propanediol and “star‐shaped” ones composed of four poly(l‐lactide) arms attached to pentaerythritol (2‐L and 4‐L polymers, respectively) with number‐average molecular weight (Mn) = 1.4–8.4 × 104g/mol were hydrolytically degraded at 37°C and pH = 7.4. The effects of the branching architecture and crystallinity on the hydrolytic degradation and crystalline morphology change were investigated. The degradation mechanism of initially amorphous and crystallized 2‐L polymers changed from bulk degradation to surface degradation with decreasing initial Mn; in contrast, initially crystallized higher molecular weight 4‐L polymer degraded via bulk degradation, while the degradation mechanism of other 4‐L polymers could not be determined. The hydrolytic‐degradation rates monitored by molecular‐weight decreases decreased significantly with increasing branch architecture and/or higher number of hydroxyl groups per unit mass. The hydrolytic degradation rate determined from the molecular weight decrease was higher for initially crystallized samples than for initially amorphous samples; however, that of 2‐L polymers monitored by weight loss was larger for initially amorphous samples than for initially crystallized samples. Initially amorphous 2‐L polymers with an Mn below 3.5 × 104g/mol crystallized during hydrolytic degradation. In contrast, the branching architecture disturbed crystallization of initially amorphous 4‐L polymers during hydrolytic degradation. All initially crystallized 2‐L and 4‐L polymers had δ‐form crystallites before hydrolytic degradation, which did not change during hydrolytic degradation. During hydrolytic degradation, the glass transition temperatures of initially amorphous and crystallized 2‐L and 4‐L polymers and the cold crystallization temperatures of initially amorphous 2‐L and 4‐L polymers showed similar changes to those reported for 1‐armed poly(l‐lactide). © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41983.
Flame retardant modification of acrylic fiber with hydrazine hydrate and sodium ions
Authors: Zhou Wanli , Yan Xiang , Liu Pengqing , Jiang Mengjin , Xu Jianjun 
Published: February 2015

ABSTRACTThe sodium ions were introduced into the acrylic fibers by post‐treating the fibers with hydrazine hydrate and aqueous sodium hydroxide to improve the flame resistance of the fibers. The molecular structure of the modified acrylic fibers was characterized by FTIR spectra. The flame resistance of the acrylic fibers was significantly increased after post‐treatment and was relied mostly on the content of sodium ions. The flame‐retardant mechanism of the modified fiber was studied in details. The micro calorimeter tests showed that the total heat release and the peak heat release rate were largely reduced after post‐treatment. Photographs of the char residues and the results of TGA and TG‐IR technique revealed that the flame retardance of the modified acrylic fiber was provided through the combination effect of the gas phase and condensed phase. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41996.
Vascularization of the Gray Whale Palate (Cetacea, Mysticeti, Eschrichtius robustus): Soft Tissue Evidence for an Alveolar Source of Blood to Baleen
Authors: Ekdale Eric G. , Deméré Thomas A. , Berta Annalisa 
Published: February 2015

ABSTRACTThe origin of baleen in mysticetes heralded a major transition during cetacean evolution. Extant mysticetes are edentulous in adulthood, but rudimentary teeth develop in utero within open maxillary and mandibular alveolar grooves. The teeth are resorbed prenatally and the alveolar grooves close as baleen germ develops. Arteries supplying blood to highly vascularized epithelial tissue from which baleen develops pass through lateral nutrient foramina in the area of the embryonic alveolar grooves and rudimentary teeth. Those vessels are hypothesized to be branches of the superior alveolar artery, but branches of the greater palatine arteries may play a role in the baleen vascularization. Through a combination of latex injection, CT, and traditional dissection of the palate of a neonatal gray whale (Eschrichtius robustus), we confirm that the baleen receives blood from vessels within the superior alveolar canal via the lateral foramina. The greater palatine artery is restricted to its own passage with no connections to the baleen. This study has implications for the presence of baleen in extinct taxa by identifying the vessels and bony canals that supply blood to the epithelium from which baleen develops. The results indicate that the lateral foramina in edentulous mysticete fossils are bony correlates for the presence of baleen, and the results can be used to help identify bony canals and foramina that have been used to reconstruct baleen in extinct mysticetes that retained teeth in adulthood. Further comparisons are made with mammals that also possess oral keratin structures, including ruminants, ornithorhynchid monotremes, and sirenians. Anat Rec, 298:691–702, 2015. © 2014 Wiley Periodicals, Inc.
Recent progress in designing inhibitors that target the drug‐resistant M2 proton channels from the influenza A viruses
Authors: Wang Jun , Li Fang , Ma Chunlong 
Published: February 2015

ABSTRACTInfluenza viruses are the causative agents for seasonal influenza, which results in thousands of deaths and millions of hospitalizations each year. Moreover, sporadic transmission of avian or swan influenza viruses to humans often leads to an influenza pandemic, as there is no preimmunity in the human body to fight against such novel strains. The metastable genome of the influenza viruses, coupled with the reassortment of different strains from a wide range of host origins, leads to the continuous evolution of the influenza virus diversity. Such characteristics of influenza viruses present a grand challenge in devising therapeutic strategies to combat influenza virus infection. This review summarizes recent progress in designing small molecule inhibitors that target the drug‐resistant influenza A virus M2 proton channels and highlights the contribution of mechanistic studies of proton conductance to drug discovery. The lessons learned throughout the course of M2 drug discovery might provide insights for designing inhibitors that target other therapeutically important ion channels. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 104: 291–309, 2015.
Cellular localization of CIP2A determines its prognostic impact in superficial spreading and nodular melanoma
Authors: Flørenes Vivi Ann , Emilsen Elisabeth , Dong Hiep Phuc , Førsund Mette , Holm Ruth , Slipicevic Ana 
Published: February 2015

AbstractCancerous inhibitor of protein phosphatase 2A (CIP2A) is an important oncogene contributing to cancer progression partially by regulating cMYC and AKT. We examined CIP2A expression in cutaneous melanomas, its association with clinicopathological parameters and mapped molecular mechanisms regulated by CIP2A in vitro. CIP2A expression was analyzed by immunohistochemistry in 17 nevi, 132 primary melanomas and 49 metastases. Effects of siRNA‐mediated down‐regulation on proliferation, apoptosis and signaling pathways were assessed in melanoma cell lines. In superficial spreading melanomas (SSM), high nuclear CIP2A expression was associated with poor overall survival (OS) (P = 0.0018). Surprisingly, high cytoplasmic expression was related to improved relapse‐free (P = 0.031) and OS (P = 0.014) in nodular melanomas (NM). In vitro experiments revealed that CIP2A can regulate proliferation and/or apoptosis partially through the PI3K/AKT pathway but also independently. In summary, CIP2A could represent a potential therapeutic target in SSM. However, in NM cytoplasmic CIP2A is associated with improved prognosis indicating that CIP2A has distinct, complex functions dependent on the molecular context and histological subtype. As seen in other cancer types, CIP2A can influence cMYC and AKT, but our data also suggest that in melanoma it has additional targets which need to be identified.
Gloss evaluation and prediction of achromatic low‐gloss textured surfaces from the automotive industry
Authors: Passaro C. , Bidoret J.S. , Baron S. , Delafosse D. , Eterradossi O. 
Published: February 2015

AbstractIn this article, we investigate the benefit of including texture information in models of gloss perception of low‐gloss textured achromatic plastic surfaces from the automotive industry. 4 models are compared: two gloss prediction models including texture information, one using data from reflectometry (M1) and one using data from goniophotometry (M2), and two models using data from reflectometry (M3) or goniophotometry (M4) alone. Both texture‐corrected models (M1‐M2) outclass the uncorrected intensity‐based models, mainly because they are made texture invariant. Although the texture‐corrected reflectometer‐based prediction (M1) correlates rather well with sensory data, a more consistent fit is obtained by mixing textural to goniophotometric data (M2). This can be explained by the fact that contrast gloss is better than multiangle specular gloss at reflecting the observer's gloss evaluation strategy. © 2015 Wiley Periodicals, Inc. Col Res Appl, 41, 154–164, 2016
Global Regularity for Some Oldroyd‐B Type Models
Authors: Elgindi Tarek M. , Rousset Frederic 
Published: February 2015

AbstractWe investigate some critical models for visco‐elastic flows of Oldroyd‐B type in dimension 2. We use a transformation that exploits the Oldroyd‐B structure to prove an L∞ bound on the vorticity which allows us to prove global regularity for our systems. © 2015 Wiley Periodicals, Inc.