bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hillslope water tracks in the High Arctic: Seasonal flow dynamics with changing water sources in preferential flow paths
Authors: Paquette Michel , Fortier Daniel , Vincent Warwick F. 
Published: March 2018

AbstractPreferential subsurface flow paths known as water tracks are often the principal hydrological pathways of headwater catchments in permafrost areas, exerting an influence on slope physical and biogeochemical processes. In polar deserts, where water resources depend on snow redistribution, water tracks are mostly found in hydrologically active areas downslope from snowdrifts. Here, we measured the flow through seeping water track networks and at the front of a perennial snowdrift, at Ward Hunt Island in the Canadian High Arctic. We also used stable isotope analysis to determine the origin of this water, which ultimately discharges into Ward Hunt Lake. These measurements of water track hydrology indicated a glacio‐nival run‐off regime, with flow production mechanisms that included saturation overland flow (return flow) in a low sloping area, throughflow or pipe‐like flow in most seepage locations, and infiltration excess overland flow at the front of the snowdrift. Each mechanism delivered varying proportions of snowmelt and ground water, and isotopic compositions evolved during the melting season. Unaltered snowmelt water contributed to >90% of total flow from water track networks early in the season, and these values fell to <5% towards the end of the melting season. In contrast, infiltration excess overland flow from snowdrift consisted of a steady percentage of snowmelt water in July (mean of 69%) and August (71%). The water seeping at locations where no snow was left in August 2015 was isotopically enriched, indicating a contribution of the upper, ice‐rich layer of permafrost to late summer discharge during warmer years. Air temperature was the main driver of snowmelt, but the effect of slope aspect on solar radiation best explained the diurnal discharge variation at all sites. The water tracks in this polar desert are part of a patterned ground network, which increases connectivity between the principal water sources (snowdrifts) and the bottom of the slope. This would reduce soil–water interactions and solute release, thereby favouring the low nutrient status of the lake.
Analysing the influences of ENSO and PDO on water discharge from the Yangtze River into the sea
Authors: Peng Jun , Luo Xiangxin , Liu Feng , Zhang Zihao 
Published: March 2018

AbstractThe El Niño Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) are two important climate oscillations that affect hydrological processes at global and regional scales. However, few studies have attempted to identify their single and combined influences on water discharge variability at multiple timescales. In this study, we examine temporal variation in water discharge from the Yangtze River into the sea and explore the influence of the ENSO and the PDO on multiscale variations in water discharge over the last century. The results of the wavelet transform analysis of the water discharge series show significant periodic variations at the interannual timescale of 2 to 8 years and the decadal timescale of 15 to 17 years. Water discharge tended to be higher during the La Niña–PDO cold phase and lower during the El Niño–PDO warm phase. The results of the cross wavelet spectrum and wavelet coherence analyses confirm the relationship between the interannual (i.e., 2 to 8 years) and decadal (i.e., 15 to 17 years) periodicities in water discharge with the ENSO and the PDO, respectively. As an important large‐scale climate background, the PDO can modulate the influence of the ENSO on water discharge variability. In general, the warm PDO enhances the influence of El Niño events, and the cold PDO enhances the influence of La Niña events. Our study is helpful in understanding the influencing mechanism of climate change on hydrological processes and provides an important scientific guideline for water resource prediction and management.
The CDKN2A polymorphisms and the susceptibility of HBV‐related gestational diabetes mellitus
Authors: Wang Shuzhen , Liu Jie , Wang Qiaolian , Du Jianguo , Wang Beibei 
Published: March 2018

BackgroundSingle‐nucleotide polymorphisms (SNPs) were discovered in HBV‐related gestational diabetes mellitus, but it still unclear whether these SNPs are associated with the susceptibility of HBV‐related gestational diabetes mellitus.MethodsThe investigation of the association between CDKN2A polymorphisms and occurrence of HBV‐related gestational diabetes mellitus (GDM) in Chinese was assessed in the case‐control study. A total of 480 pregnant patients with HBV and 530 pregnant controls were consecutively recruited from January 2015 to December 2016. Polymerase chain reaction‐restriction fragment length polymorphisms (PCR‐RFLP) method was applied to measure genotyping for the detection of CDKN2A.ResultsThe significant differences in the frequency of CDKN2A genotype distributions, rs10811661 and rs564398, were found by Chi‐square test. Using conditional logistic analysis, individuals carrying the CDKN2A rs10811661 TC and TT genotypes and CDKN2A rs564398 AA and AG genotypes were related to a greater risk of HBV‐related GDM compared with the genotype.ConclusionsIn conclusion, the CDKN2A rs10811661 and rs564398 polymorphisms showed association with a greater risk of HBV‐related GDM in a Chinese population.
A novel mutation in SLC39A14 causing hypermanganesemia associated with infantile onset dystonia
Authors: Juneja Monica , Shamim Uzma , Joshi Aditi , Mathur Aaradhna , Uppili Bharathram , Sairam Smitha , Ambawat Sakshi , Dixit Rashmi , Faruq Mohammed 
Published: March 2018

AbstractBackgroundMutations in SLC39A14 cause a recessive disorder of manganese (Mn) metabolism that manifests as childhood onset progressive neurodegeneration characterized by parkinsonism and dystonia.MethodsThe present study genetically investigated a case of hypermanganesemia. We describe a family where an affected child with a history of progressive neurodegeneration showed symptoms of dystonia with increased levels of blood Mn and altered signal intensities in globus pallidus and dentate nucleus. Whole exome sequencing was conducted to genetically investigate the pathology in the child, which allowed us to identify a novel homozygous causal mutation in SLC39A14.ResultsInsilico modeling of the novel homozygous causal mutation in SLC39A14 predicted that it was deleterious, affecting Mn binding and transportation of metal by transmembrane instability of the protein structure. The clinical features of other reported mutations in SLC39A14 were also reviewed and the clinical spectrum in our case conforms to the described neurological abnormalities.ConclusionsWe conclude that the mutation identified in SLC39A14 in our case is a novel variation linked to recessive disorders of hypermaganesemia and dystonia.
Perinatal Outcomes of Fetal Lower Urinary Tract Obstruction After Vesicoamniotic Shunting Using a Double‐Basket Catheter
Authors: Jeong Ba‐Da , Won Hye‐Sung , Lee Mi‐Young 
Published: March 2018

ObjectivesTo evaluate the perinatal survival and renal function of fetuses with lower urinary tract obstruction (LUTO) who underwent vesicoamniotic shunting using a double‐basket catheterMethodsWe retrospectively reviewed 32 fetuses with LUTO who underwent vesicoamniotic shunting using a double‐basket catheter between 1998 and 2013.ResultsAmong the 32 fetuses examined, 5 died because of termination of pregnancy, and 2 died in utero. The median gestational age at diagnosis was 15.5 (range, 10.0–27.3) weeks, and that at initial shunting was 17.1 (range, 12.3–32.2) weeks. Shunt dislocation or occlusion occurred in 18 of 42 procedures (42.8%). The median gestational age at delivery for the 25 live births was 35.5 (range, 28–40) weeks. Postnatal diagnosis revealed posterior urethral valves in 15 fetuses, a cloacal anomaly in 7, and urethral stenosis in 3. Three neonatal deaths occurred, resulting in an overall perinatal survival rate of 68.8% (22 of 32). The rates of normal renal function were 40.6% (13 of 32) at 28 days and 40% (10 of 25) at 2 years after birth. The absence of oligohydramnios after shunting was the only prognostic factor for normal renal function at 2 years (P < .05).ConclusionsVesicoamniotic shunting may be helpful for fetuses with LUTO.
Papillary Thyroid Carcinoma Recurrence: Low Yield of Neck Ultrasound With an Undetectable Serum Thyroglobulin Level
Authors: Epstein Samantha , McEachern Rachel , Khot Rachita , Padia Shetal , Patrie James T. , Itri Jason N. 
Published: March 2018

ObjectivesTo assess the yield of neck ultrasound (US) when serum thyroglobulin (Tg) is undetectable (<0.1 ng/mL) compared to elevated serum Tg in patients with differentiated papillary thyroid carcinoma (PTC) treated with thyroidectomy and radioactive iodine 131 (RAI) ablation.MethodsA retrospective chart review was conducted from 2010 through 2015 at an academic institution evaluating US results in patients with serum Tg levels obtained within 6 months of a neck US examination after thyroidectomy and RAI. The reference standard for recurrence was pathologic results from US‐guided fine‐needle aspiration (FNA) or follow‐up for at least 1 year.ResultsAmong 76 patients with undetectable serum Tg levels, there were 19 examinations in 18 patients in which US raised the possibility of recurrence. None of these 18 patients had recurrence by FNA (n = 8) or clinical follow‐up of at least 1 year (n = 10). Among 65 patients with elevated serum Tg levels, there were 24 examinations in 22 patients in which US raised the possibility of recurrence. Twelve patients underwent FNA, with 9 patients (34.6%) showing PTC; 7 patients had follow‐up neck US examinations showing stability of findings; and 3 patients were lost to follow up. The yield of neck US was significantly lower when serum Tg was undetectable compared to when levels were elevated (P = .001).ConclusionsNeck US did not identify recurrent PTC when the serum Tg level was undetectable in patients who underwent total thyroidectomy and RAI therapy. Eliminating neck US when serum TG levels are undetectable could decrease unnecessary imaging examinations without negatively affecting the ability to detect recurrent disease.
To dam, or not to dam? Abolishment of further flooding impedes the natural revegetation processes after long‐term fluvial deposition of copper tailings
Authors: Nikolic Nina , Kostic Ljiljana , Nikolic Miroslav 
Published: March 2018

AbstractLong‐term potentials and constraints of nature to spontaneously recover after severe degradation by toxic mine waste, and general principles of mutual modifications of spontaneous vegetation and soils during this process, have remained widely unknown. This study investigates the effect of flooding on natural restoration of a model locality in Eastern Serbia, complexly degraded by 70‐years fluvial deposition of sulfidic copper (Cu) mine tailings in a floodplain along 80 km of the polluted river flow. We analyzed multivariate response of forest vegetation (floristic and structural parameters) together with physical and chemical properties of concomitant soils and sediments. Floods strongly modify the interactions between soil and vegetation. Three very different types of forest vegetation constitute the response of the nature to key soil adverse factors (excessive Cu availability, low nutrients, and low pH); combined with drought, these constraints completely inhibit revegetation. Continual flooding after mine closure, despite the pollution it still brings in, fosters a faster development of highly specialized vegetation and most importantly faster buildup of soil organic matter necessary for phytostabilization of substantial amounts of Cu tailings present in the floodplain. We show that enhanced nutrient fluxes facilitated by natural flooding regime might overrun the constraining effect of deposited Cu also for natural vegetation.
Structural heterogeneity of vegetation fire ash
Authors: Brook Anna , Wittenberg Lea , Kopel Daniella , Polinova Maria , Roberts Dar , Ichoku Charles , Shtober‐Zisu Nurit 
Published: March 2018

AbstractAny wildfire generates ash, the solid residue derived from burning biomass. Vegetation fire ash consists of charred organic material, charcoal, and inorganic mineral substances. Recent studies identified ash deposits as a dual system: soil and ash strata. The addition of ash to the soil profile alters soil properties and dynamics. A thorough analysis of ash–soil profile reveals a structural appearance of thin laminas. The laminas differ in a variety of physical properties and mineral composition. This research aims at assessing the unique properties of ash–soil profiles by performing an infrared spectroscopic study and statistical analysis. For that purpose, several laboratory experiments were conducted. The paper presents semiquantitative results of spectral analysis calculated by 4 statistical methods. The results indicate a well‐established laminar structure of the ash and evaluate the characteristics of each lamina. The proposed methodology was examined under real‐world conditions; a field experiment of 2‐m2 parcel with in situ O horizon was flamed and burned out. The field samples illustrated the formation of microlaminas, which proved to be similar to the laboratory samples. This detailed approach may promote a better understanding of the complex nature to the ash, the ash–soil interactions and its effect on the edaphic ecosystem.
The role of rapid glacier retreat and landscape transformation in controlling the post‐Little Ice Age evolution of paraglacial coasts in central Spitsbergen (Billefjorden, Svalbard)
Authors: Strzelecki Mateusz C. , Long Antony J. , Lloyd Jeremy M. , Małecki Jakub , Zagórski Piotr , Pawłowski Łukasz , Jaskólski Marek W. 
Published: March 2018

AbstractIn Svalbard, the rapid glacier retreat observed since the end of the Little Ice Age (LIA) has transformed the geomorphology and sediment budgets of glacial forelands, river valleys, and slope systems. To date, relatively little information exists regarding the impact of such a profound glacial landscape degradation on the evolution of coastal environment. This paper addresses this deficiency by detailing the post‐LIA sediment fluxes to the coastal zone in Billefjorden, central Spitsbergen (Svalbard). We analysed the response of the gravel‐dominated barrier coast to the decay of Ferdinandbreen, one of the fastest retreating glaciers in the region. Glacier retreat resulted in the development of paraglacial sediment cascade where eroded and reworked glacigenic sediments progressed through alluvial fans to the coast, thus feeding gravel‐dominated spit systems in Petuniabukta. We demonstrated that the coastal systems in central Spitsbergen responded abruptly to post‐LIA climatic changes. The acceleration of coastal erosion and associated spit development was coincident with rapid climate warming that dates from the 1980s and has been associated with longer ice‐free periods and activation of multiple sediment supply sources from the deglaciated landscape. In colder phases of post‐LIA period, coastal zone development was subdued and strongly dependent on the efficiency of sediment transport via in a longshore drift. Finally, we discuss the differences in the post‐LIA coastal responses between central Spitsbergen and western Spitsbergen highlighting the efficiency of paraglacial sediment delivery from land to the coast controlled by the state of glacial systems, bedrock topography, and development of river channels.
Addition of silver nanoparticles has no long‐term effects on natural phytoplankton community dynamics in a boreal lake
Authors: Conine Andrea L. , Rearick Daniel C. , Paterson Michael J. , Xenopoulos Marguerite A. , Frost Paul C. 
Published: March 2018

AbstractLake phytoplankton communities are dynamic with well‐documented seasonal variability in taxonomic composition and biomass. However, this variability has been largely overlooked when assessing the risk posed to aquatic ecosystems by the antimicrobial agent, silver nanoparticles (AgNPs). Here, we report results from a whole lake AgNP addition study at the IISD‐Experimental Lakes Area that assessed the effects of AgNPs on phytoplankton. Phytoplankton communities were largely unaffected in terms of taxonomy, pigment concentration, and biomass by AgNP additions. These negative toxicological results are due to community changes being more strongly affected by natural processes, such as temperature and dissolved nutrients. We conclude that AgNP exposure at environmentally relevant concentrations for 2 yr did not affect phytoplankton communities in boreal lakes, which emphasizes the importance of incorporating natural variability into analyses that attempt to determine the effect of contaminants on aquatic ecosystems.
Change in BMI Distribution over a 24‐Year Period and Associated Socioeconomic Gradients: A Quantile Regression Analysis
Authors: Gebremariam Mekdes K. , Arah Onyebuchi A. , Lien Nanna , Naess Oyvind , Ariansen Inger , Kjollesdal Marte K. 
Published: March 2018

ObjectiveThis study assessed the change in body mass index (BMI) distribution among 18‐ or 19‐year‐olds over 24 years. It also investigated parallel changes in the distribution of birth weight and in the association between birth weight and later risk of overweight and/or obesity. Parental educational variations in the trends and associations were explored.MethodsThe study used data on 606,832 male military conscripts enlisted between 1985 and 2008. Quantile regression was used to assess the temporal change in BMI and birth weight distribution. The association between birth weight and overweight and/or obesity at age 18 or 19 years was quantified by using logistic regression.ResultsIncreases in BMI over time were found namely in the 90th, 95th, 97th, and 99th percentiles. Socioeconomic differences in this increase were documented in the 75th to 97th percentiles. The distribution of birth weight and the association between birth weight and the risk of overweight and/or obesity at age 18 or 19 years remained stable over time.ConclusionsThe difference in the increase in BMI between low and high percentiles indicates the limited role of mean BMI in reflecting population changes. The results suggest a need to focus on those with low socioeconomic position in the upper ends of the BMI distribution to combat increasing disparities in obesity‐related outcomes.
Multiple shape memory behaviors of natural Eucommia ulmoides rubber and polybutene‐1 composites
Authors: Wang Yan , Geng Jieting , Xia Lin , Xin Zhenxiang 
Published: March 2018

AbstractWe fabricated a series of novel shape memory composites using natural Eucommia ulmoides rubber (EUR) and polybutene‐1 (PB‐1) as basic materials for the first time. The shape memory composites were prepared via simple physical blending and chemical crosslinking methods with co‐continuous architecture and multiple shape memory behaviors. These composites and their preparation methods might be widely used in the field of heat shrinkable tubes. We studied the mechanical, thermal and shape memory properties of the composites, and proposed schemes to explain their dual and triple shape memory effects. In the EUR/PB‐1 composites, both the crosslinking network of the composites and crystalline regions of PB‐1 could function as the fixed domain, and the crystalline zones of EUR and PB‐1 could act as the reversible domain individually or jointly. The composites exhibited excellent dual shape memory properties with blending ratios of 90/10 and 80/20, and good triple shape memory properties with blending ratios of 70/30 and 60/40. © 2018 Society of Chemical Industry
Enhancing antibacterial properties of polypropylene/Cu‐loaded montmorillonite nanocomposite filaments through sheath–core morphology
Authors: Roy Anasuya , Joshi Mangala 
Published: March 2018

AbstractPolypropylene (PP) loaded with copper‐exchanged montmorillonite (Cu‐MMT) nanocomposite filaments and films with excellent antimicrobial activity have been reported for the first time. A sheath–core morphology filament in which only the sheath contains Cu‐MMT was prepared for maximizing bioactivity. Sodium MMT clay was modified to acid‐activated MMT and further to Cu‐MMT via an ion exchange process. The exchange operation was confirmed using wide‐angle X‐ray diffraction and energy‐dispersive X‐ray spectroscopy (EDX) which suggested increased interlayer spacing and confirmed the loading of copper in Cu‐MMT. Further, Cu‐MMT was melt‐mixed in PP in the form of PP/Cu‐MMT nanocomposite filament, film and sheath–core morphology PP/Cu‐MMT nanocomposite filament. The surface morphology and elemental composition of the nanocomposites were studied using scanning electron microscopy coupled with EDX. Transmission electron micrographs were obtained to understand the dispersion characteristics of Cu‐MMT phase in PP. X‐ray diffraction analysis of nanocomposites suggested increased crystallinity at lower loading due to heterogeneous nucleating action of MMT. The PP nanocomposite filaments and films were tested for antimicrobial activity against Gram‐negative bacterium Escherichia coli, which is the main pathogenic bacterium found abundantly in water, and were found to exhibit excellent antimicrobial activity. © 2018 Society of Chemical Industry
The influence of short chain branch on formation of shish‐kebab crystals in bimodal polyethylene under shear at high temperatures
Authors: Wang Zongbao , Mao Yimin , Jarumaneeroj Chatchai , Thitisak Boonyakeat , Tiyapiboonchaiya Piyawan , Rungswang Wonchalerm , Hsiao Benjamin S. 
Published: March 2018

ABSTRACTFormation of shish‐kebab crystals due to the coil–stretch transition under shear in the molten state using a bimodal polyethylene system with high molecular weight (HMW) fraction having different branch content was investigated. In specific, in situ small‐angle X‐ray scattering (SAXS) and wide‐angle X‐ray diffraction (WAXD) techniques were used to study the structure evolution of shish‐kebab crystals at high temperatures under simple shear. The SAXS results revealed that with the increase of branch content, shish‐kebab crystals became more stable at high temperatures (e.g., 139 °C). However, the shish length of the bimodal PE containing 0.11% branch was shorter than that with no branch. The WAXD results showed that the degree of crystallization for bimodal PE with HMW fraction having 0.11% branch increased with time but reached a plateau value of 1%, while that with no branch increased continuously till 11%. Furthermore, the crystal orientation of bimodal PE with HMW fraction having 0.11% branch was above 0.9 and maintained at a constant value, while that with no branch decreased from 0.9 to 0.1 upon relaxation. This study indicates that even though the crystallizability of the HMW fraction with branch content decreased, they could effectively stabilize the shear‐induced crystalline structure with shorter shish‐kebab crystals. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018, 56, 786–794