bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of baseflow in dissolved solids delivery to streams in the Upper Colorado River Basin
Authors: Rumsey Christine A. , Miller Matthew P. , Schwarz Gregory E. , Hirsch Robert M. , Susong David D. 
Published: October 2017

AbstractSalinity has a major effect on water users in the Colorado River Basin, estimated to cause almost $300 million per year in economic damages. The Colorado River Basin Salinity Control Program implements and manages projects to reduce salinity loads, investing millions of dollars per year in irrigation upgrades, canal projects, and other mitigation strategies. To inform and improve mitigation efforts, there is a need to better understand sources of salinity to streams and how salinity has changed over time. This study explores salinity in the baseflow fraction of streamflow, assessing whether groundwater is a significant contributor of dissolved solids to streams in the Upper Colorado River Basin (UCRB). Chemical hydrograph separation was used to estimate baseflow discharge and baseflow dissolved solids loads at stream gages (n = 69) across the UCRB. On average, it is estimated that 89% of dissolved solids loads originate from the baseflow fraction of streamflow, indicating that subsurface transport processes play a dominant role in delivering dissolved solids to streams in the UCRB. A statistical trend analysis using weighted regressions on time, discharge, and season was used to evaluate changes in baseflow dissolved solids loads in streams (n = 27) from 1986 to 2011. Decreasing trends in baseflow dissolved solids loads were observed at 63% of streams. At the three most downstream sites, Green River at Green River, UT, Colorado River at Cisco, UT, and the San Juan River near Bluff, UT, baseflow dissolved solids loads decreased by a combined 823,000 metric tons (mT), which is approximately 69% of projected basin‐scale decreases in total dissolved solids loads as a result of salinity control efforts. Decreasing trends in baseflow dissolved solids loads suggest that salinity mitigation projects, landscape changes, and/or climate are reducing dissolved solids transported to streams through the subsurface. Notably, the pace and extent of decreases in baseflow dissolved solids loads declined during the most recent decade; average decreasing loads during the 2000s (28,200 mT) were only 54% of average decreasing loads in the 1990s (51,700 mT).
Natural enamel caries in quinoline: Volumetric data and the pattern of infiltration
Authors: de Mattos Brito Camila Santos , Meira Kássia Regina Simões , de Sousa Frederico Barbosa 
Published: October 2017

AbstractThis study aimed to test the hypotheses that (i) a parameter related to permeability, αd (ratio of squared water volume by the nonmineral volume) is, among all major component volumes (mineral, water, and organic volumes) the best predictor of quinoline infiltration in natural enamel caries (NEC), and (ii) the pore volume fraction infiltrated by quinoline (Vqui) in NEC is much lower than previous estimates that neglected water and organic enamel volumes. Mineral and nonmineral volumes and αd were measured at 341 histological points (from 20 approximal NEC lesions), and transport of quinoline was tracked by orientation‐independent polarizing microscopy. R2 values of Vqui were 0.596 (αd), 0.033 (mineral volume), 0.474 (water volume), and 0.011 (organic volume). Vqui values were 23% (body of the lesion), 7% (dark zone), and 9% (translucent zone), lower than previous estimates (with high effect size). Transport of quinoline occurred both parallelly and perpendicularly to prism paths, and dark zones were seen where only transport parallel to prisms occurred. In conclusion, αd was the main predictor of quinoline infiltration, but it differed from the water volume with a small effect size, and the pore volume fraction with quinoline was much lower than previous estimates.
Effects of EDTA gel and chlorhexidine gel on root dentin permeability
Authors: Bighetti Trevisan Rayana Longo , Scatolin Renata Siqueira , Castro Raucci Larissa Moreira Spinola de , Raucci Neto Walter , Froner Izabel Cristina 
Published: October 2017

AbstractThe aim of this study was to evaluate the effect of 24% ethylenediaminetetraacetic acid (EDTA) gel and 2% chlorhexidine gel (CHX) in dentin permeability and smear layer removal from root canals instrumented with NiTi rotary system using histochemical staining and scanning electron microscopy (SEM) analysis. Overall, 43 premolars were classified into two experimental groups, EDTA (n = 20) and CHX (n = 20), and a negative control (NC) (n = 3). All specimens were instrumented and the irrigant solutions were used after each file change. The EDTA group received a final rinse with 5‐ml 1% NaOCl followed by a 5‐ml 0.9% saline solution; the CHX group received a final rinse with 10‐ml 0.9% saline solution; and the negative control group received a final rinse with only 0.9% saline solution. Fifteen teeth from each group were prepared for histochemical staining and evaluation of dentin permeability using the image‐scanning software Axion Vision (v.4.8.2). Five remaining teeth were prepared for analysis using SEM for morphological analysis. The study found that 24% EDTA gel increased the permeability of dentin in all thirds evaluated and also demonstrated an increased cleaning ability, with dentinal walls free of smear layer and open dentinal tubules, as compared to 2% CHX gel. It was concluded that EDTA was efficient in cleaning the dentinal tubules and increased dentin permeability.
Not just a bump on the head: ultrasound as first‐line imaging in a boy with Pott's puffy tumour
Authors: Reddan Tristan , Connor Patricia 
Published: October 2017

AbstractWhile computed tomography (CT) and magnetic resonance imaging (MRI) have established roles in evaluating Pott's puffy tumour, ultrasound can play a valuable role in identifying the condition, particularly in children. We present the case of a boy with a fluctuant forehead lump and headaches, where ultrasound was the first‐line imaging modality and expedited further investigations.
Post‐Crosslinked Polyurethanes with Excellent Shape Memory Property
Authors: Liu Wenkai , Zhao Yun , Wang Rong , Li Jiehua , Li Jianshu , Luo Feng , Tan Hong , Fu Qiang 
Published: October 2017

AbstractShape‐memory polymers are highly desirable in implant biomaterials for minimally invasive surgical procedures. However, most of them lack suitable transition temperature, mechanical properties, and biodegradability. Here, a series of shape‐memory polyurethanes are synthesized by postcrosslinking in hard‐segment domains using a flexible crosslinker. The materials used are all nontoxic and biodegradable. Through postcrosslinking of unsaturated linear polyurethanes with flexible and biodegradable crosslinker, the crosslinked polyurethanes (CPUs) show good mechanical properties, excellent shape‐memory property, and repeatability. The post‐crosslinking structure and shape‐memory mechanism of CPUs are investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, and dynamic mechanical analysis tests. The crosslinker endows the fixed phase enough crosslinking and inserts in the hard segments to give the fixed phase certain elasticity. The elastic hard segments make them form more hydrogen bonds with soft segments during shape deformation. The low‐molecular‐weight poly (ε‐caprolactone) offers the samples a shape‐memory transition temperature at around 37 °C, which is suitable for implant devices in vivo. This work expands CPUs with an elastic crosslinking structure as potential candidates for implant biomaterials. Since the post‐crosslinking polymerization is facile, it can be convenient for industrial production.
Sleep fragmentation and Parkinson's disease pathology in older adults without Parkinson's disease
Authors: Sohail Shahmir , Yu Lei , Schneider Julie A. , Bennett David A. , Buchman Aron S. , Lim Andrew S. P. 
Published: October 2017

ABSTRACTIntroductionPatients with Parkinson's disease (PD) frequently experience disrupted sleep, and several sleep abnormalities are associated with an increased risk of incident PD. However, there are few data concerning the relationship between objectively quantified sleep disruption and the cardinal histopathological features of PD, especially in individuals without clinical PD.MethodsWe studied 269 older adults without PD who had participated in the Rush Memory and Aging Project and undergone uniform structured neuropathologic evaluations upon death. Sleep fragmentation was measured using actigraphy. Logistic regression models examined the associations of sleep fragmentation proximate to death with the burden of Lewy body pathology and substantia nigra neuron loss.ResultsGreater sleep fragmentation was associated with the presence of Lewy body pathology (odds ratio 1.40; 95% confidence interval 1.05‐1.86; P = .02) and substantia nigra neuron loss (odds ratio 1.43; 95% confidence interval 1.10‐1.88; P = .008) and a higher odds of a pathological diagnosis of PD (odds ratio 2.04; 95% confidence interval 1.34‐3.16; P = .0009). These associations were independent of motor features of parkinsonism, demographic characteristics, and a wide range of medical co‐morbidities.ConclusionsSleep fragmentation is associated with PD pathology in older adults without PD. These results suggest that sleep fragmentation may be a marker of or risk factor for PD pathology in older adults without PD. © 2017 International Parkinson and Movement Disorder Society
Structural abnormality of substantia nigra induced by methamphetamine abuse
Authors: Rumpf Jost‐Julian , Albers Jana , Fricke Christopher , Mueller Wolf , Classen Joseph 
Published: October 2017

ABSTRACTBackground: Methamphetamine abuse has been linked to an increased risk of Parkinson's disease.Objective: The objective of this study was to investigate structural abnormality of the substantia nigra in past methamphetamine users using transcranial sonography.Methods: In a cross‐sectional, observational study, echogenicity of the substantia nigra was assessed in 59 past methamphetamine users and 59 matched controls. The frequencies of an abnormal spatial extension of the substantia nigra as well as the average sizes of left and right substantia nigra were evaluated.Results: The average echogenic size of the substantia nigra was larger in methamphetamine users (0.22 ± 0.06 cm2) when compared with controls (0.17 ± 0.05 cm2, P < .001). Furthermore, the frequency of enlarged, echogenic substantia nigra was increased in methamphetamine users (42% vs 12% in controls, P < .001). Partial correlation analysis revealed an association of echogenic substantia nigra size with estimated total lifetime intake of methamphetamine (r55 = 0.395, P = .002).Conclusions: Current data link methamphetamine abuse in humans to injury of substantia nigra neurons and an increased risk of Parkinson's disease. © 2017 International Parkinson and Movement Disorder Society
Magnetic resonance molecular imaging of metastatic breast cancer by targeting extradomain‐B fibronectin in the tumor microenvironment
Authors: Han Zheng , Cheng Han , Parvani Jenny G. , Zhou Zhuxian , Lu Zheng‐Rong 
Published: October 2017

PurposeNon‐invasive early accurate detection of malignant breast cancer is paramount to the clinical management of the life‐threatening disease. Here, we aim to test a small peptide targeted MRI contrast agent, ZD2‐Gd(HP‐DO3A), specific to an oncoprotein, extradomain‐B fibronectin (EDB‐FN), in the tumor microenvironment for MR molecular imaging of breast cancer.MethodEDB‐FN expression in 4T1 and MDA‐MB‐231 cancers was analyzed with quantitative real‐time PCR and western blot. Primary and metastatic triple negative breast cancer mouse models were developed using 4T1 and MDA‐MB‐231 cells. Contrast‐enhanced MRI was carried out to evaluate the use of ZD2‐Gd(HP‐DO3A) in detecting 4T1 and MDA‐MB‐231 primary and metastatic tumors.ResultsEDB‐FN was abundantly expressed in the extracellular matrix (ECM) of both the primary and metastatic TNBC tumors. In T1‐weighted MRI, ZD2‐Gd(HP‐DO3A) generated superior contrast enhancement in primary TNBC tumors than a nonspecific clinical agent Gd(HP‐DO3A), during 30 min after contrast injection. ZD2‐Gd(HP‐DO3A) also produced a significant increase in contrast‐to‐noise ratio (CNR) of TNBC metastases, enabling sensitive localization and delineation of metastases that occulted in non‐contrast‐enhanced or Gd(HP‐DO3A)‐enhanced MRI.ConclusionsThese findings potentiate the use of ZD2‐Gd(HP‐DO3A) for MR molecular imaging of malignant breast cancers to improve the healthcare of breast cancer patients. Magn Reson Med 79:3135–3143, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
The Impact of Incentives to Recruit and Retain Teachers in “Hard‐to‐Staff” Subjects
Authors: Feng Li , Sass Tim R. 
Published: October 2017

AbstractWe investigate the effects of a statewide program designed to increase the supply of teachers in designated “hard‐to‐staff” areas, such as special education, math, and science. Employing a difference‐in‐difference estimator we find that the loan forgiveness component of the program was effective, reducing mean attrition rates for middle and high school math and science teachers by 10.4 percent and 8.9 percent, respectively. We also find that the impact of loan forgiveness varied with the generosity of payments; when fully funded, the program reduced attrition of special education teachers by 12.3 percent, but did not have a statistically significant impact when funding was substantially reduced. A triple‐difference estimate indicates that a one‐time bonus program also had large effects, reducing the likelihood of teachers’ exit by as much as 32 percent in the short run. A back‐of‐the‐envelope cost‐benefit analysis suggests that both the loan forgiveness and the bonus program were cost effective.
Mycobacterium tuberculosis UvrB forms dimers in solution and interacts with UvrA in the absence of ligands
Authors: Lahiri Samarpita , Rizzi Menico , Rossi Franca , Miggiano Riccardo 
Published: October 2017

AbstractDuring its life cycle Mycobacterium tuberculosis (MTB) must face a variety of environmental and endogenous physical and chemical stresses that could produce genotoxic damage. However, MTB possesses efficient systems to counteract the harmful effects of DNA‐damaging assaults. The nucleotide excision repair (NER) is a highly conserved multi‐enzymatic cascade that is initiated by the concerted action of three core proteins, that is UvrA, UvrB, and UvrC. Although the functional roles of these enzymes are well characterized, the intra‐pathway coordination of the NER components and the dynamics of their association is still a matter of debate. In the presented study, we analyzed the hydrodynamic properties and the oligomeric state of the MTB UvrB protein (MtUvrB) that we expressed and purified to homogeneity in a tag‐free form. Our results show that, differently to what has been previously observed for the His‐tagged version of the protein, MtUvrB forms dimers in solution, which are characterized by an elongated shape, as determined by small‐angle X‐ray scattering analysis. Moreover, to gain insights into the mycobacterial UvrA/UvrB lesion sensing/tracking complex we adopted a size‐exclusion chromatography‐based approach, revealing that the two proteins interact in the absence of ligands, leading to the assembling of A2B2 hetero‐tetramers in solution. Surface plasmon resonance analysis showed that the dissociation constant of the MtUvrA/MtUvrB complex falls in the low micromolar range that could represent the basis for a fine modulation of the complex architecture accompanying the multi‐step DNA repair activity of mycobacterial NER.
Lifestyle migration and settler colonialism: The imaginative geographies of British migrants to Aotearoa New Zealand
Authors: Higgins Katie W. 
Published: October 2017

AbstractThis paper explores the imaginative geographies of relatively privileged migrants living in settler societies for their colonial continuities. It responds to a recent call to historicise the cultural significance attached to migration and destinations in lifestyle migration research through an exploration of some of the potential synergies between the newly emergent field of settler colonial studies and lifestyle migration. The analysis draws on 12 months of qualitative research with British migrants living in Auckland, Aotearoa New Zealand. First, it examines the ambivalent affective associations of “islandness” and distance, as both insulating and isolating. Second, the paper explores the twinned appreciation of spectacular, empty natural surroundings, and a perception of a “lack” of culture and history. It is argued, first, that the geographical and historical interpellation of the country as “at the end of the world” and as “young” recentres distant Euro‐colonial cultures and decentres Māori cultures. And, second, that the intersections of contemporary lifestyle migration and settler colonialism are an important avenue for future research.
Mechanism and selectivity of rhodium‐catalyzed CH bond arylation of indoles
Authors: Santoro Stefano , Himo Fahmi 
Published: October 2017

AbstractDensity functional theory calculations are used to study the reaction mechanism and origins of C2‐selectivity in a rhodium‐catalyzed arylation of indole. It is shown that the reaction is catalyzed by an anionic Rh(III)‐intermediate that activates the substrate through a concerted‐metalation deprotonation. Dissociation of pivalic acid and subsequent reductive elimination generate the arylated indole product. Oxidative addition of the aryl iodide and a subsequent ligand exchange regenerates the active catalytic species. The origin of the regioselectivity is found to be the more favorable interaction between the 2‐indolyl fragment and the metal center compared to the 3‐indolyl fragment. Moreover, the better interaction of the pivalate ligands with the substrate in the transition state for the activation of C2H compared to the transition state for the C3H activation further favors the C2‐selectivity.
Role of purines on the copper‐catalyzed oxidative damage in biological systems: Protection versus promotion
Authors: Castañeda‐Arriaga Romina , Pérez‐González Adriana , Alvarez‐Idaboy Juan Raúl , Galano Annia 
Published: October 2017

AbstractOxidative damage to biomolecules is a serious health‐threatening issue, which leads to the development of several diseases. Oxidative conditions are frequently catalyzed by metal ions. In this study, the role of purines in the copper‐catalyzed oxidative stress was investigated using the density functional theory. The obtained results indicate that purines can have a dual behavior, acting as both protectors and promoters of oxidative stress. Their protection role arises from their known radical scavenging activity, as well as their ability to chelate Cu(II) leading to complexes that are—to some extent—harder to reduce than free Cu(II). Conversely, their pro‐oxidant role is a consequence of their reductant behavior, when deprotonated. Thus, the purines’ anions can reduce Cu(II) to Cu(I), making the latter available to be involved in Fenton‐like reactions. Consequently, mixtures of purines and Cu(II), at pHs where the fraction of deprotonated purines is rather significant, would yield •OH radicals. In turn, these very reactive radicals would damage biological targets such as lipids, proteins, and DNA.
Goals and principles for programmatic river restoration monitoring and evaluation: collaborative learning across multiple projects
Authors: Weber Christine , Åberg Ulrika , Buijse Anthonie D. , Hughes Francine M.R. , McKie Brendan G. , Piégay Hervé , Roni Phil , Vollenweider Stefan , Haertel‐Borer Susanne 
Published: October 2017

River restoration is a relatively recent undertaking, with high levels of complexity and uncertainty involved. Many restoration projects have been monitored over the past three decades, however, results have rarely been compared across projects thereby limiting our ability to identify factors that influence restoration outcomes. Programmatic monitoring and evaluation (ProME) that builds on standardized surveys and systematic cross‐project comparison allows for collaborative learning, transfer of results across restoration projects and for adaptive management and monitoring. We present a conceptual framework for ProME consisting of four goals and nine principles. First, ProME accounts for complexity, uncertainty, and change in order to contribute to sustainable river management over the long term. Second, ProME promotes collaborative learning and adaptation by standardizing the sampling design for the field surveys at multiple projects and by disseminating findings across stakeholders. Third, ProME verifies to what extent restoration has been achieved, i.e., it must quantify the size and direction of change. Fourth, ProME identifies why the observed effects were present, thereby improving our mechanistic understanding of river functioning. We conclude with potential extensions of the framework (e.g., evaluating cumulative effects of projects within a catchment). Our conceptual framework presents a structured approach toward a more systematic learning and evidence‐based action in river restoration, while taking into account the wider picture of environmental change within which river restoration projects will inevitably operate. WIREs Water 2018, 5:e1257. doi: 10.1002/wat2.1257This article is categorized under:

Water and Life > Conservation, Management, and Awareness
Water and Life > Methods
The rapid development of bespoke small unmanned aircraft
Authors: Paulson C. A. , Sóbester A. , Scanlan J. P. 
Published: October 2017

ABSTRACTThe ability to quickly fabricate small unmanned aircraft system (sUAS) through Additive Manufacturing (AM) methods opens a range of new possibilities for the design and optimisation of these vehicles. In this paper, we propose a design loop that makes use of surrogate modelling and AM to reduce the design and optimisation time of scientific sUAS. AM reduces the time and effort required to fabricate a complete aircraft, allowing for rapid design iterations and flight testing. Co-Kriging surrogate models allow data collected from test flights to correct Kriging models trained with numerically simulated data. The resulting model provides physically accurate and computationally cheap aircraft performance predictions. A global optimiser is used to search this model to find an optimal design for a bespoke aircraft. This paper presents the design loop and a case study which demonstrates its application.