bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hydroxy fatty acids in snow pit samples from Mount Tateyama in central Japan: Implications for atmospheric transport of microorganisms and plant waxes associated with Asian dust
Authors: Tyagi Poonam , Kawamura Kimitaka , Bikkina Srinivas , Mochizuki Tomoki , Aoki Kazuma 
Published: November 2016

AbstractWe report here the source apportionment of atmospheric soil microorganisms and higher plant metabolites based on chemical markers (hydroxy fatty acids: FAs) in the snowpack samples collected from Mount Tateyama in central Japan during spring 2009 (N = 6) and 2011 (N = 7). A homologous series of β‐hydroxy FAs (C9–C20), constituents of Gram‐negative bacteria (GNB), in snowpacks clearly suggest a long‐range atmospheric transport of dust‐associated bacteria followed by scavenging by snowflakes. Similarly, higher atmospheric abundances of α‐(C16–C32) and ω‐(C9–C30)‐hydroxy FAs in the snow layers containing Asian dust revealed contributions from soil microbes and higher plant epicuticular waxes. Moreover, covariation between the concentrations of hydroxy FAs and water‐soluble Ca2+ (dust tracer), together with calculated air mass backward trajectories, demonstrated their source regions such as the Taklamakan Desert, Gobi Desert, and Loess Plateau. A close match of molecular distributions of hydroxy FAs (with the predominance of ω‐ and β‐isomers) is noteworthy between snowpack (present study) and springtime aerosols from Chichijima Island in the western North Pacific (WNP). This observation suggests a “below‐cloud scavenging” of transported dust particles and associated soil microbes in the East Asian outflow by snowflakes. These distributions are, however, contrary to those observed in the fresh snow samples from Sapporo, northern Japan (predominance of α‐hydroxy FAs), which could be explained by “in‐cloud” microbial oxidation processes. This comparison, therefore, provides additional insights regarding the aeolian transport of soil microbes in the East Asian outflow to the WNP, which has not been available.
Impulse waves generated by snow avalanches: Momentum and energy transfer to a water body
Authors: Zitti Gianluca , Ancey Christophe , Postacchini Matteo , Brocchini Maurizio 
Published: November 2016

AbstractWhen a snow avalanche enters a body of water, it creates an impulse wave whose effects may be catastrophic. Assessing the risk posed by such events requires estimates of the wave's features. Empirical equations have been developed for this purpose in the context of landslides and rock avalanches. Despite the density difference between snow and rock, these equations are also used in avalanche protection engineering. We developed a theoretical model which describes the momentum transfers between the particle and water phases of such events. Scaling analysis showed that these momentum transfers were controlled by a number of dimensionless parameters. Approximate solutions could be worked out by aggregating the dimensionless numbers into a single dimensionless group, which then made it possible to reduce the system's degree of freedom. We carried out experiments that mimicked a snow avalanche striking a reservoir. A lightweight granular material was used as a substitute for snow. The setup was devised so as to satisfy the Froude similarity criterion between the real‐world and laboratory scenarios. Our experiments in a water channel showed that the numerical solutions underestimated wave amplitude by a factor of 2 on average. We also compared our experimental data with those obtained by Heller and Hager (2010), who used the same relative particle density as in our runs, but at higher slide Froude numbers.
A detached eddy simulation model for the study of lateral separation zones along a large canyon‐bound river
Authors: Alvarez Laura V. , Schmeeckle Mark W. , Grams Paul E. 
Published: November 2016

AbstractLateral flow separation occurs in rivers where banks exhibit strong curvature. In canyon‐bound rivers, lateral recirculation zones are the principal storage of fine‐sediment deposits. A parallelized, three‐dimensional, turbulence‐resolving model was developed to study the flow structures along lateral separation zones located in two pools along the Colorado River in Marble Canyon. The model employs the detached eddy simulation (DES) technique, which resolves turbulence structures larger than the grid spacing in the interior of the flow. The DES‐3D model is validated using Acoustic Doppler Current Profiler flow measurements taken during the 2008 controlled flood release from Glen Canyon Dam. A point‐to‐point validation using a number of skill metrics, often employed in hydrological research, is proposed here for fluvial modeling. The validation results show predictive capabilities of the DES model. The model reproduces the pattern and magnitude of the velocity in the lateral recirculation zone, including the size and position of the primary and secondary eddy cells, and return current. The lateral recirculation zone is open, having continuous import of fluid upstream of the point of reattachment and export by the recirculation return current downstream of the point of separation. Differences in magnitude and direction of near‐bed and near‐surface velocity vectors are found, resulting in an inward vertical spiral. Interaction between the recirculation return current and the main flow is dynamic, with large temporal changes in flow direction and magnitude. Turbulence structures with a predominately vertical axis of vorticity are observed in the shear layer becoming three‐dimensional without preferred orientation downstream.
Rapid degradation of permafrost underneath waterbodies in tundra landscapes—Toward a representation of thermokarst in land surface models
Authors: Langer M. , Westermann S. , Boike J. , Kirillin G. , Grosse G. , Peng S. , Krinner G. 
Published: November 2016

AbstractWaterbodies such as lakes and ponds are abundant in vast Arctic landscapes and strongly affect the thermal state of the surrounding permafrost. In order to gain a better understanding of the impact of small‐ and medium‐sized waterbodies on permafrost and the formation of thermokarst, a land surface model was developed that can represent the vertical and lateral thermal interactions between waterbodies and permafrost. The model was validated using temperature measurements from two typical waterbodies located within the Lena River delta in northern Siberia. Impact simulations were performed under current climate conditions as well as under a moderate and a strong climate‐warming scenario. The performed simulations demonstrate that small waterbodies can rise the sediment surface temperature by more than 10°C and accelerate permafrost thaw by a factor of between 4 and 5. Up to 70% of this additional heat flux into the ground was found to be dissipated into the surrounding permafrost by lateral ground heat flux in the case of small, shallow, and isolated waterbodies. Under moderate climate warming, the lateral heat flux was found to reduce permafrost degradation underneath waterbodies by a factor of 2. Under stronger climatic warming, however, the lateral heat flux was too small to prevent rapid permafrost degradation. The lateral heat flux was also found to strongly impede the formation of thermokarst. Despite this stabilizing effect, our simulations have demonstrated that underneath shallow waterbodies (<1 m), thermokarst initiation happens 30 to 40 years earlier than in simulations without preexisting waterbody.
Rock fracture grouting with microbially induced carbonate precipitation
Authors: Minto James M. , MacLachlan Erica , El Mountassir Gráinne , Lunn Rebecca J. 
Published: November 2016

AbstractMicrobially induced carbonate precipitation has been proposed for soil stabilization, soil strengthening, and permeability reduction as an alternative to traditional cement and chemical grouts. In this paper, we evaluate the grouting of fine aperture rock fractures with calcium carbonate, precipitated through urea hydrolysis, by the bacteria Sporosarcina pasteurii. Calcium carbonate was precipitated within a small‐scale and a near field‐scale (3.1 m2) artificial fracture consisting of a rough rock lower surfaces and clear polycarbonate upper surfaces. The spatial distribution of the calcium carbonate precipitation was imaged using time‐lapse photography and the influence on flow pathways revealed from tracer transport imaging. In the large‐scale experiment, hydraulic aperture was reduced from 276 to 22 μm, corresponding to a transmissivity reduction of 1.71 × 10−5 to 8.75 × 10−9 m2/s, over a period of 12 days under constantly flowing conditions. With a modified injection strategy a similar three orders of magnitude reduction in transmissivity was achieved over a period of 3 days. Calcium carbonate precipitated over the entire artificial fracture with strong adhesion to both upper and lower surfaces and precipitation was controlled to prevent clogging of the injection well by manipulating the injection fluid velocity. These experiments demonstrate that microbially induced carbonate precipitation can successfully be used to grout a fracture under constantly flowing conditions and may be a viable alternative to cement based grouts when a high level of hydraulic sealing is required and chemical grouts when a more durable grout is required.
Arbitrarily complex chemical reactions on particles
Authors: Benson David A. , Bolster Diogo 
Published: November 2016

AbstractPrevious particle‐tracking (PT) algorithms for chemical reaction conceptualize each particle being composed of one species. Reactions occur by either complete or partial birth/death processes between interacting particles. Here we extend the method by placing any number of chemical species on each particle. The particle/particle interaction is limited to mass exchange. After exchange, reactions of any sort are carried out independently on each particle. The novel components of the algorithms are verified against analytic solutions where possible.
Unilobar surgery for symptomatic epileptic spasms
Authors: Barba Carmen , Mai Roberto , Grisotto Laura , Gozzo Francesca , Pellacani Simona , Tassi Laura , Francione Stefano , Giordano Flavio , Cardinale Francesco , Guerrini Renzo 
Published: November 2016

AbstractObjectiveTo assess factors associated with favorable seizure outcome after surgery for symptomatic epileptic spasms and improve knowledge on pathophysiology of this seizure type.MethodsInclusion criteria were: (1) age between 6 months and 15 years at surgery; (2) active epileptic spasms; (3) follow‐up after surgery >1 year.ResultsWe retrospectively studied 80 children (aged 1.3 ± 2 years at seizure onset; 5.8 ± 4 years at surgery, 11.7 ± 5.7 years at last follow up). Magnetic resonance imaging (MRI) revealed structural abnormalities in 77/80 patients (96.3%; unilateral in 69: 89.6%). We performed invasive recordings in 24 patients (30%). In 21 patients in whom MRI or histopathology detected a lesion, electrodes exploring it constantly captured initial ictal activity at spasm onset. Fifty‐eight patients (72.5%) underwent unilobar and 22 (27.5%) multilobar or hemispheric procedures. At last follow‐up, 49 patients (61.3%) were in Engel class I. Multivariate logistic models showed completeness of resection of the seizure onset zone (OR = 0.016, 95%CI: 0.002, 0.122) and of the MRI visible lesion (OR = 0.179, 95% CI: 0.032, 0.999) to be significantly associated with Engel class IA outcome. Unfavorable outcome was associated with an older age at surgery, when it reflected a longer duration of epilepsy (OR = 1.383, 95% CI: 0.994,1.926).InterpretationData emerging from invasive recordings and the good seizure outcome following removal of discrete epileptogenic lesions support a focal cortical origin of spasms. In patients with discrete epileptogenic lesions, the pragmatic approach to surgery should follow the same principles applied to focal epilepsy favoring, whenever possible, unilobar, one‐stage resections.
AV‐1451 tau and β‐amyloid positron emission tomography imaging in dementia with Lewy bodies
Authors: Kantarci Kejal , Lowe Val J. , Boeve Bradley F. , Senjem Matthew L. , Tosakulwong Nikki , Lesnick Timothy G. , Spychalla Anthony J. , Gunter Jeffrey L. , Fields Julie A. , Graff‐Radford Jonathan , Ferman Tanis J. , Jones David T. , Murray Melissa E. , Knopman David S. , Jack Clifford R. , Petersen Ronald C. 
Published: November 2016

ObjectivePatients with probable dementia with Lewy bodies (DLB) often have Alzheimer's disease (AD)‐related pathology. Our objective was to determine the pattern of positron emission tomography (PET) tau tracer AV‐1451 uptake in patients with probable DLB, compared to AD, and its relationship to β‐amyloid deposition on PET.MethodsConsecutive patients with clinically probable DLB (n = 19) from the Mayo Clinic Alzheimer's Disease Research Center underwent magnetic resonance imaging, AV‐1451, and Pittsburgh compound‐B (PiB) PET examinations. Age‐ and sex‐matched groups of AD dementia (n = 19) patients and clinically normal controls (n = 95) from an epidemiological cohort served as a comparison groups. Atlas‐ and voxel‐based analyses were performed.ResultsThe AD dementia group had significantly higher AV‐1451 uptake than the probable DLB group, and medial temporal uptake completely distinguished AD dementia from probable DLB. Patients with probable DLB had greater AV‐1451 uptake in the posterior temporoparietal and occipital cortex compared to clinically normal controls, and in probable DLB, the uptake in these regions correlated with global cortical PiB uptake (Spearman rho = 0.63; p = 0.006).InterpretationMedial temporal lobe AV‐1451 uptake distinguishes AD dementia from probable DLB, which may be useful for differential diagnosis. Elevated posterior temporoparietal and occipital AV‐1451 uptake in probable DLB and its association with global cortical PiB uptake suggest an atypical pattern of tau deposition in DLB. ANN NEUROL 2017;81:58–67
Mutation in noncoding RNA RNU12 causes early onset cerebellar ataxia
Authors: Elsaid Mahmoud Fawzi , Chalhoub Nader , Ben‐Omran Tawfeg , Kumar Pankaj , Kamel Hussein , Ibrahim Khalid , Mohamoud Yasmin , Al‐Dous Eman , Al‐Azwani Iman , Malek Joel A. , Suhre Karsten , Ross M. Elizabeth , Aleem Alice Abdel 
Published: November 2016

ObjectiveExome sequences account for only 2% of the genome and may overlook mutations causing disease. To obtain a more complete view, whole genome sequencing (WGS) was analyzed in a large consanguineous family in which members displayed autosomal recessively inherited cerebellar ataxia manifesting before 2 years of age.MethodsWGS from blood‐derived genomic DNA was used for homozygosity mapping and a rare variant search. RNA from isolated blood leukocytes was used for quantitative polymerase chain reaction (PCR), RNA sequencing, and comparison of the transcriptomes of affected and unaffected family members.ResultsWGS revealed a point mutation in noncoding RNA RNU12 that was associated with early onset cerebellar ataxia. The U12‐dependent minor spliceosome edits 879 known transcripts. Reverse transcriptase PCR demonstrated minor intron retention in all of 9 randomly selected RNAs from this group, and RNAseq showed splicing disruption specific to all U12‐type introns detected in blood monocytes from affected individuals. Moreover, 144 minor intron–containing RNAs were differentially expressed, including transcripts for 3 genes previously associated with cerebellar neurodegeneration.InterpretationInterference with particular spliceosome components, including small nuclear RNAs, cause reproducible uniquely distributed phenotypic and transcript‐specific effects, making this an important category of disease‐associated mutation. Our approach to differential expression analysis of minor intron–containing genes is applicable to other diseases involving altered transcriptome processing. ANN NEUROL 2017;81:68–78
Mitigating Tensions over Land Conversion in Papua, Indonesia
Authors: Indrawan Mochamad , Caldecott Julian , Ermayanti  
Published: November 2016

AbstractIn the south of the biodiversity‐rich Indonesian province of Papua, a large agricultural program is planned for the districts around Merauke, with the ostensible aim of helping to meet Indonesia's food requirements. Questions arise over the scheme's compliance with national laws and sustainability policies, as well as its likely impacts on indigenous livelihoods and biodiversity. It is also contrary to the recent low‐carbon development priorities of the provincial and national governments. For the initiative to be consistent with law and policy, therefore, considerably improved planning effort would be needed, taking into account many factors that have so far been ignored.
Highly Fluorescent Non‐Conventional Boron‐Difluoride‐Based π Organogel with Gelation‐Assisted Piezochromism
Authors: Wang Sa , Lan Haichuang , Xiao Shuzhang , Tan Ronghua , Lu Yunxiang 
Published: November 2016

AbstractTriphenylamine‐functionalized boron 2‐(2′‐pyridyl)imidazole complex bearing no alkyl chains or H‐bond unit was found to be able to gelate a series of solvents, and the balanced intermolecular π–π interactions play an important role in its supramolecular self‐assembly. The gelator molecule is piezochromic, and the dried gel responded to pressure more sensitively than regular crystalline powder.
Measurement of caffeine and its three primary metabolites in human plasma by HPLC‐ESI‐MS/MS and clinical application
Authors: Chen Feng , Hu Zhe‐Yi , Parker Robert B. , Laizure S. Casey 
Published: November 2016

AbstractCaffeine is a mild stimulant with significant potential for abuse, being consumed in larger doses with the widespread availability of energy drinks and by novel routes of administration such as inspired powder, oral sprays and electronic cigarettes. How these recent changes in caffeine consumption affecting caffeine disposition and abuse potential is of growing concern. In the study of caffeine disposition in humans, it is common to only measure the caffeine concentration; however, caffeine's three major metabolites (paraxanthine, theobromine and theophylline) retain central nervous system stimulant activity that may contribute to the overall pharmacological activity and toxicity. Therefore, it would be scientifically more rigorous to measure caffeine and its major metabolites in the evaluation of caffeine disposition in human subjects. Herein, we report a method for the simultaneous quantification of caffeine and its three major metabolites in human plasma by high‐performance liquid chromatography coupled to electrospray tandem mass spectrometry (HPLC‐ESI‐MS/MS). Human plasma samples were treated by simple protein precipitation and the analytes were separated using a 6 min gradient program. Precision and accuracy were well within in the 15% acceptance range. The simple sample preparation, short runtime, sensitivity and the inclusion of caffeine's major metabolites make this assay methodology optimal for the study of caffeine's pharmacokinetics and pharmacodynamics in human subjects.
Planar PtPd3 Complexes Stabilized by Three Bridging Silylene Ligands
Authors: Tanabe Makoto , Yumoto Ryouhei , Yamada Tetsuyuki , Fukuta Tomoko , Hoshino Tsuyoshi , Osakada Kohtaro , Tanase Tomoaki 
Published: November 2016

AbstractA heterobimetallic PtPd3 complex supported by three bridging diphenylsilylene ligands, [Pt{Pd(dmpe)}3(μ3‐SiPh2)3] (1, dmpe=1,2‐bis(dimethylphosphino)ethane), has been synthesized from mononuclear Pd and Pt complexes. The hexagonal core composed of Pt, Pd, and Si atoms is slightly larger than that of the tetrapalladium complex, [Pd{Pd(dmpe)}3(μ3‐SiPh2)3] (2). Reaction of PhSiH3 with complex 1 in the presence and absence of Ph2SiH2 results in the formation of a tetranuclear complex with silyl and hydride ligands at the Pt center, [PtH(SiPh2H){Pd(dmpe)}3(μ3‐SiHPh)3] (3), and an octanuclear complex, [{Pt{Pd(dmpe)}3(μ3‐SiHPh)3}2(κ2‐dmpe)] (5), respectively. Both M−Si (M=Pt, Pd) bond lengths and the 29Si NMR chemical shifts of 1 and 2 are located between those of mononuclear late transition‐metal complexes with a silylene ligand and complexes with donor‐stabilized silylene ligands. CuI and AgI adducts of 1 and 2, formulated as [M(μ‐M′I){Pd(dmpe)}3(μ3‐SiPh2)3] (M=Pt, Pd; M′=Cu, Ag), undergo elimination of CuI (AgI) and regenerate the tetrametallic complexes upon heating or addition of a chelating diphosphine. Elimination of AgI from 2‐AgI occurs more rapidly than elimination of CuI from 2‐CuI, as determined from the results of kinetics experiments.
Carbon lost and carbon gained: a study of vegetation and carbon trade‐offs among diverse land uses inPhoenix,Arizona
Authors: McHale Melissa R. , Hall Sharon J. , Majumdar Anandamayee , Grimm Nancy B. 
Published: November 2016

AbstractHuman modification and management of urban landscapes drastically alters vegetation and soils, thereby altering carbon (C) storage and rates of net primary productivity (NPP). Complex social and ecological processes drive vegetation cover in cities, leading to heterogeneity in C dynamics depending on regional climate, land use, and land cover. Recent work has demonstrated homogenization in ecological processes within human‐dominated landscapes (the urban convergence hypothesis) in soils and biotic communities. However, a lack of information on vegetation in arid land cities has hindered an understanding of potential C storage andNPPconvergence across a diversity of ecosystem types. We estimated C storage andNPPof trees and shrubs for six different land‐use types in the arid metropolis of Phoenix, Arizona,USA, and compared those results to native desert ecosystems, as well as other urban and natural systems around the world. Results from Phoenix do not support the convergence hypothesis. In particular, C storage in urban trees and shrubs was 42% of that found in desert vegetation, whileNPPwas only 20% of the totalNPPestimated for comparable natural ecosystems. Furthermore, the overall estimates of C storage andNPPassociated with urban trees in theCAPecosystem were much lower (8–63%) than the other cities included in this analysis. We also found that C storage (175.25–388.94 g/m2) andNPP(8.07–15.99 g·m−2·yr−1) were dominated by trees in the urban residential land uses, while in the desert, shrubs were the primary source for pools (183.65 g/m2) and fluxes (6.51 g·m−2·yr−1). These results indicate a trade‐off between shrubs and trees in arid ecosystems, with shrubs playing a major role in overall C storage andNPPin deserts and trees serving as the dominant C pool in cities. Our research supports current literature that calls for the development of spatially explicit and standardized methods for analyzing C dynamics associated with vegetation in urbanizing areas.