bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessing the impact of land use change on aridification in semiarid land
Authors: Emadodin Iraj , Reinsch Thorsten 
Published: July 2018

AbstractIn this study, aridification as an environmental challenge was investigated in detail. Regional meteorological data and climate indices as diagnostic tools have been used to detect the temporal trend of aridification over the past six decades in Tehran City. For this purpose, annual time‐series (1951–2010) of temperature, precipitation, relative humidity, and visibility as well as the climate indices (Johansson continentality index, De Martonne aridity/humidity index, Pinna combinative index, discomfort index, and potential evapotranspiration) have been selected. The study focuses on Tehran, the largest urban area in western Asia and a complex socio‐economic region (with around 8.3 million people). Mann–Kendall test was used to determine temporal trends in the climate indices and meteorological data. The results show that the climate components are strongly affected by the rapid urbanization and land‐use change during the last six decades. The De Martonne and Pinna combinative indices show high variations in the analyzed periods. The results show positive trend in visibility and temperature. Discomfort condition and potential evapotranspiration have been calculated for two separate temporal periods (1951–1975 and 1976–2010). Temporal distribution of discomfort index shows more than half of the population feels discomfort in July after rapid urbanization during 1976–2010. The potential evapotranspiration shows an increase during 1976–2010 period compared with the 1951–1975 period. The threshold of growing aridity in the area under investigation is mainly due to an increase of annual temperature that effects on the potential evapotranspiration.
Interrelationships between terrace development, topography, soil erosion, and soil dislocation by tillage in Minchet Catchment, Ethiopian Highlands
Authors: Subhatu Alemtsehay , Speranza Chinwe Ifejika , Zeleke Gete , Roth Vincent , Lemann Tatenda , Herweg Karl , Hurni Hans 
Published: July 2018

AbstractThis study assesses the interrelationships between terrace development and topographic factors, soil erosion, and soil dislocation by tillage in Minchet Catchment in the Ethiopian Highlands. Data were collected through a mix of modelling soil erosion using the Universal Soil Loss Equation adapted to Ethiopia, and measuring slope and soil deposition above the terraces. The terraces, which developed over 29 years following construction of fanya juu bunds on cropland, reduced the cropland's current slope gradient to half of its original slope, leading to about 39% less soil erosion. Currently, of the total 50 t · ha−1 · yr−1 soil deposition measured above the terraces, about 22 t · ha−1 · yr−1 was soil eroded by water, and the other 28 t · ha−1 · yr−1 was soil that had been dislocated by tillage. This shows that Soil and Water Conservation technologies in the study area are effective in reducing slope gradient and slope length, and thus also in trapping eroded soil, slowing soil movement by tillage, and ultimately, in reducing soil erosion. However, current soil loss from the fields still exceeds the soil formation rate of the study area. We thus highlight possible options to further reduce soil erosion in the crop fields, such as increasing the number of terraces in areas with wider spacing and growing multipurpose and productive grasses and trees on terraces.
Two threatened Caribbean coral species have contrasting responses to combined temperature and acidification stress
Authors: Langdon Chris , Albright Rebecca , Baker Andrew C. , Jones Paul 
Published: July 2018

AbstractThere is growing evidence that different coral species and algal symbionts (Symbiodinium spp.) can vary greatly in their response to rising temperatures and also ocean acidification. In a fully crossed factorial experimental design, two threatened Caribbean reef‐building coral species, Acropora cervicornis hosting a mixture of Symbiodinium clades A and C and Orbicella faveolata hosting Symbiodinium D, were exposed to combinations of a normal (26°C) and elevated (32°C) temperature and normal (380 ppm) and elevated (800 ppm) CO2 for 62 d and then recovered at 26°C and 380 ppm or 32°C and 380 ppm for an additional 56 d. CO2 enrichment did not confer enhanced thermal tolerance as had been suggested in other studies. A. cervicornis was more sensitive to heat stress (maximum monthly mean + 1.5°C) experiencing 100% mortality after 25 d while all O. faveolata survived. Conversely, O. faveolata was more sensitive to high CO2 experiencing a 47% reduction in growth while A. cervicornis experienced no significant reduction. It is predicted that A. cervicornis is unlikely to survive past 2035. O. faveolata with D symbionts might survive to 2060 and later but its abundance will be impacted by CO2 effects on recruitment potential.
Waters under Artificial Lights: Does Light Pollution Matter for Aquatic Primary Producers?
Authors: Grubisic Maja 
Published: July 2018

AbstractBright night lights have become a symbol of development and prosperity in the modern world. But have you ever wondered how artificial light at night (ALAN) may be affecting living beings in our cities, and how it may be affecting us? As artificial illumination is transforming nocturnal environments around the world, light pollution associated with its use is becoming a topic of increasing interest in the scientific and public communities. Light pollution disrupts natural light regimes in many regions of the world, raising concerns about ecological and health impacts of this novel anthropogenic pressure. Most obviously, ALAN can influence night‐active animals in urban and suburban areas, and most research in this growing field focuses on terrestrial organisms such as bats, birds, and insects. Effects on aquatic ecosystems are much less known. In particular, aquatic primary producers, such as microalgae, cyanobacteria, and plants, have rarely been studied despite their critical positioning in the base of aquatic food webs and the fundamental role that light plays in their ecology. For primary producers, light is a key source of both energy and environmental information; it influences their growth, production, and community structure. ALAN has therefore a large potential to influence their communities and induce bottom‐up changes to aquatic ecosystems and ecosystem functions.
Hybrid Polypeptide/Polylactide Copolymers with Short Phenylalanine Blocks
Authors: Mayans Enric , Murase Sara K. , Pérez‐Madrigal Maria M. , Cativiela Carlos , Alemán Carlos , Puiggalí Jordi 
Published: July 2018

AbstractHybrid copolymers constituted by short l‐phenylalanine (Phe) blocks (i.e., Phen with n ranging from 2 to 25) and l‐lactide blocks of different length are synthesized and characterized. The diblock structure is obtained by ring opening polymerization of lactide using a Phe‐oligopeptide as macroinitiator. The length of the poly(l‐lactide) (PLLA) block is controlled through the [lactide]/[macroinitiator] ratio. Morphologic studies of such hybrid copolymers indicate that the assembly of PLLA can be controlled by introducing short Phe blocks. Spherulites with both positive and negative birefringence are achieved in melt crystallization as a consequence of different lamellar distributions. Instead, a high variety of structures are detected in solution‐crystallized samples. Specifically, lozenge single crystals, flower‐like crystals, fibrillar structures, compact spheres, ringed sperulites, dendritic structures, microfibers, and braid‐like microstructures are observed. Some of the detected morphologies are characteristic of self‐assembled Phe‐oligopeptides, suggesting that Phe‐blocks play a crucial role in the self‐assembly properties.
Content overlap analysis of 64 (hypo)mania symptoms among seven common rating scales
Authors: Chrobak Adrian A. , Siwek Marcin , Dudek Dominika , Rybakowski Janusz K. 
Published: July 2018

AbstractObjectivesFried () quantified the overlap of items among seven widely used depression rating scales. The analysis revealed substantial heterogeneity of the depressive syndromes and a low overlap among the scales. To our best knowledge, there are no studies evaluating the content overlap of (hypo)mania scales. The goal of our study, therefore, is to quantify the overlap of items among seven widely used (hypo)manic scales, implementing the methodology developed by Fried ().MethodsSeven commonly used (hypo)manic scales underwent content analysis. Symptom overlap was evaluated with the use of the Jaccard index (0 = no overlap, 1 = full overlap). In case of every scale, rates of idiosyncratic symptoms and rates of specific versus compound symptoms were calculated.ResultsThe seven scales gathered 64 hypo(manic) symptoms. The mean overlap among all of the instruments was low (0.35), the mean overlap of each scale with all others ranged from 0.29% to 0.48%, and the overlap among individual scales ranged from 0.20% to 0.65. Thirty‐six percent of symptoms appeared only on one scale. Only 6% of the symptoms appeared on all of the instruments.ConclusionsWe have shown that using (hypo)manic scales as interchangeable measurements may be problematic.
Homonuclear decoupling by projection reconstruction
Authors: Görling Benjamin , Bermel Wolfgang , Bräse Stefan , Luy Burkhard 
Published: July 2018

AbstractSimilar to J‐resolved spectroscopy, also, heteronuclear multiple bond correlation (HMBC), heteronuclear single bond correlation (HSBC), and heteronuclear multiple quantum coherence (HMQC) types of correlation experiments result in homonuclear tilted multiplet patterns. On the example of the high‐resolution heteronuclear single bond correlation (HR‐HSBC) pulse sequence, it is shown how the tilt angle can be varied within a wide range of positive and negative values. Projection along the tilt angles in all cases results in homonuclear decoupling. Using well‐known projection reconstruction techniques, the different tilt angles can be used to reconstruct a homonuclear decoupled two‐dimensional correlation spectrum. The concept is proven and further refined by segmental projection reconstruction and the use of a clean in‐phase heteronuclear single quantum correlation (CLIP‐HSQC) spectrum with an effective zero tilt angle for further filtering. The proof of principle, its application to one‐bond coupling measurement, as well as a basic HMBC, and a detailed discussion with comparison to other homodecoupling techniques are given.
Gradient‐controlled local Larmor adjustment (GC‐LOLA) for simultaneous multislice bSSFP imaging with improved banding behavior
Authors: Stäb Daniel , Speier Peter 
Published: July 2018

PurposeSimultaneous multislice (SMS) accelerated balanced SSFP (bSSFP) imaging can be impaired by off‐resonance effects, due to slice‐specific alterations in the frequency response. In this work, we introduce gradient‐controlled local Larmor adjustment as a means to restore the frequency response and to stabilize SMS‐accelerated bSSFP imaging with respect to banding artifacts.MethodsProviding each simultaneously excited slice with an individual RF phase cycle in SMS‐accelerated bSSFP imaging results in the sequence's frequency response being shifted slice‐specifically along the off‐resonance axis. The net available pass‐band for imaging is effectively reduced, increasing the measurement's susceptibility toward B0 inhomogeneities. To overcome these issues, gradient‐controlled local Larmor adjustment modifies the Larmor frequency locally and aligns the slice‐specific frequency responses on resonance by (1) unbalancing the slice gradient by a small constant amount and (2) modifying the RF phase cycles homogeneously across all slices. The concept is investigated using simulations and phantom experiments and applied to SMS‐accelerated bSSFP cine cardiovascular MR at 3 T.ResultsPhantom and in vivo measurements demonstrate the successful removal of banding artifacts and restoration of the bSSFP frequency response using gradient‐controlled local Larmor adjustment. For large slice thicknesses and small slice distances, banding artifacts become slightly widened.ConclusionGradient‐controlled local Larmor adjustment successfully restores the frequency response in SMS‐accelerated bSSFP imaging without increasing the sequence's susceptibility toward eddy current effects. The concept facilitates combinations of the different SMS encoding concepts and provides a powerful way to actively control off‐resonance effects in slice‐accelerated bSSFP imaging.
Black blood myocardialT2mapping
Authors: Wang Chengyan , Jang Jihye , Neisius Ulf , Nezafat Maryam , Fahmy Ahmed , Kang Jinkyu , Rodriguez Jennifer , Goddu Beth , Pierce Patrick , Berg Sophie , Zhang Jue , Wang Xiaoying , Nezafat Reza 
Published: July 2018

PurposeTo develop a black blood heart‐rate adaptive T2‐prepared balanced steady‐state free‐precession (BEATS) sequence for myocardial T2mapping.MethodsIn BEATS, blood suppression is achieved by using a combination of preexcitation and double inversion recovery pulses. The timing and flip angles of the preexcitation pulse are auto‐calculated in each patient based on heart rate. Numerical simulations, phantom studies, and in vivo studies were conducted to evaluate the performance of BEATS. BEATS T2maps were acquired in 36 patients referred for clinical cardiac MRI and in 1 swine with recent myocardial infarction. Two readers assessed all images acquired in patients to identify the presence of artifacts associated with slow blood flow.ResultsPhantom experiments showed that the BEATS sequence provided accurate T2values over a wide range of simulated heart rates. Black blood myocardial T2maps were successfully obtained in all subjects. No significant difference was found between the average T2measurements obtained from the BEATS and conventional bright‐blood T2; however, there was a decrease in precision using the BEATS sequence. A suppression of the blood pool resulted in sharper definition of the blood–myocardium border and reduced partial voluming effect. The subjective assessment showed that 16% (18 out of 108) of short‐axis slices have residual blood artifacts (12 in the apical slice, 4 in the midventricular slice, and 2 in the basal slice).ConclusionThe BEATS sequence yields dark blood myocardial T2maps with better definition of the blood–myocardium border. Further studies are warranted to evaluate diagnostic accuracy of black blood T2mapping.
Motion compensation using principal component analysis and projection onto dipole fields for abdominal magnetic resonance thermometry
Authors: Tan Jeremy , Mougenot Charles , Pichardo Samuel , Drake James M. , Waspe Adam C. 
Published: July 2018

PurposeHigh intensity focused ultrasound (HIFU) has the potential to locally and non‐invasively treat cancer with fewer side effects than alternative therapies. However, motion and tissue heterogeneity in the abdomen can compromise the HIFU focus and confound current thermometry methods.MethodsThe proposed thermometry method combines principal component analysis (PCA), as a multi‐baseline technique, and projection onto dipole fields (PDF), as a near‐referenceless method. PCA forgoes tracking tools by projecting incoming images onto a subspace spanning the motion history. PDF is subsequently used to synthesize the naturally feasible components of the residual phase using a magnetic dipole model. This leaves only the phase shifts that are induced by HIFU.ResultsWith in vivo measurements, in porcine and human kidneys, the mean pixel‐wise temperature SD was 0.86 ± 0.41°C in selected regions of interest (ROIs) across all data sets, without any user‐interaction or supplementary tracking tools. This is an improvement over a benchmark hybrid method, which scored 1.36 ± 1.20°C on the same data. Uncorrected subtraction of the data yielded a score of 3.02 ± 2.87°C.ConclusionThe PCA‐PDF hybrid method achieves superior artifact correction by exploiting the motion history and intrinsic magnetic susceptibility of the underlying tissue.
Evaluating the accuracy of multicomponent T2 parameters for luminal water imaging of the prostate with acceleration using inner‐volume 3DGRASE
Authors: Chan Rachel W. , Lau Angus Z. , Detzler Garry , Thayalasuthan Vivekanandan , Nam Robert K. , Haider Masoom A. 
Published: July 2018

PurposeProstate cancer can be detected using a multicomponent T2 mapping technique termed luminal water imaging. The purpose of this study is twofold: 1) To accelerate the luminal water imaging acquisition by using inner volume selection as part of a gradient and spin echo sequence, and 2) to evaluate the accuracy of luminal water fractions and multicomponent T2 relaxation times.MethodsThe accuracy of parameter estimates was assessed using Monte Carlo simulations, in phantom experiments and in the prostate (in 5 healthy subjects). Two fitting methods, nonnegative least squares and biexponential fitting with stimulated echo correction, were compared.ResultsResults demonstrate that inner volume selection in a gradient and spin echo sequence is effective for accelerating prostate luminal water imaging by at least threefold. Evaluation of the accuracy shows that the estimated luminal water fractions are relatively accurate, but the short‐ and long‐T2 relaxation times should be interpreted with caution in noisy scenarios (SNR < 100) and when the corresponding fractions are small ( < 0.5). The mean luminal water fractions obtained at SNR above 100 are 0.27 ± 0.07 for the peripheral zone for both fitting methods, 0.16 ± 0.04 for the transition zone with nonnegative least squares, and 0.16 ± 0.03 for the transition zone with biexponential fitting including stimulated echo correction.ConclusionThe shortened scan duration allows the luminal water imaging sequence to be easily integrated into a standard multiparametric prostate MRI protocol.
Dynamic off‐resonance correction for spiral real‐time MRI of speech
Authors: Lim Yongwan , Lingala Sajan Goud , Narayanan Shrikanth S. , Nayak Krishna S. 
Published: July 2018

PurposeTo improve the depiction and tracking of vocal tract articulators in spiral real‐time MRI (RT‐MRI) of speech production by estimating and correcting for dynamic changes in off‐resonance.MethodsThe proposed method computes a dynamic field map from the phase of single‐TE dynamic images after a coil phase compensation where complex coil sensitivity maps are estimated from the single‐TE dynamic scan itself. This method is tested using simulations and in vivo data. The depiction of air–tissue boundaries is evaluated quantitatively using a sharpness metric and visual inspection.ResultsSimulations demonstrate that the proposed method provides robust off‐resonance correction for spiral readout durations up to 5 ms at 1.5T. In ‐vivo experiments during human speech production demonstrate that image sharpness is improved in a majority of data sets at air–tissue boundaries including the upper lip, hard palate, soft palate, and tongue boundaries, whereas the lower lip shows little improvement in the edge sharpness after correction.ConclusionDynamic off‐resonance correction is feasible from single‐TE spiral RT‐MRI data, and provides a practical performance improvement in articulator sharpness when applied to speech production imaging.
Sources of hepatic glycogen synthesis in mice fed with glucose or fructose as the sole dietary carbohydrate
Authors: Jarak Ivana , Barosa Cristina , Martins Fatima O. , Silva Joao C. P. , Santos Cristiano , Belew Getachew Debas , Rito Joao , Viegas Ivan , Teixeira Jose , Oliveira Paulo J. , Jones John G. 
Published: July 2018

PurposeThe positional analysis of hepatic glycogen enrichment from deuterated water (2H2O) by 2H NMR has been applied previously to resolve the contributions of glucose and fructose to glycogen synthesis in rodents fed a high sucrose diet. To further validate this method, this analysis was applied to mice fed with synthetic diets whose carbohydrate components consisted solely of either glucose or fructose.MethodsEight glucose‐fed and 12 fructose‐fed mice were given 2H2O followed by ad libitum feeding overnight. Mice were then euthanized, hepatic glycogen was isolated and derivatized to monoacetone glucose, and 2H‐enrichment of positions 2, 5, and 6S were measured by 2H NMR. From these data, the fraction of overnight glycogen appearance from the direct pathway and/or glycogen cycling and indirect pathway were estimated. Indirect pathway fractions were resolved into Krebs cycle and triose‐phosphate sources—the latter including contributions from fructose metabolism.ResultsAfter overnight feeding, the fraction of overnight glycogen appearance derived from direct pathway and/or glycogen cycling in glucose‐fed‐mice was 63 ± 1%. For the indirect pathway, Krebs cycle and triose‐phosphate sources contributed 22 ± 1% and 15 ± 1%, respectively. For fructose‐fed‐mice, glycogen appearance was dominated by triose‐phosphate sources (60 ± 2%) with lesser contributions from Krebs cycle (14 ± 1%) and direct and/or glycogen cycling (26 ± 2%).Conclusions2H NMR analysis of hepatic glycogen 2H enrichment from 2H2O provides realistic profiles of dietary glucose and fructose contributions to hepatic glycogen synthesis in mice fed with diets containing 1 or the other sugar as the sole carbohydrate source.
A critical appraisal of the principal guidelines for neurogenic lower urinary tract dysfunction using the AGREE II instrument
Authors: Jaggi Ashley , Drake Marcus , Siddiqui Emad , Nazir Jameel , Giagos Vasileios , Fatoye Francis 
Published: July 2018

AimsThe process of identifying research questions, synthesizing and interpreting evidence, and weight given to health economics differs between the clinical guidelines (CGs) for neurogenic lower urinary tract dysfunction (NLUTD). Consequently, the quality also varies which can have implications for clinical practice.MethodsWe used the Appraisal of Guidelines for Research and Evaluation II (AGREE II) instrument to assess the quality of the National Institute for Health and Care Excellent (NICE), European Association of Urology (EAU), and the International Consultations on Incontinence (ICI) CGs on neurogenic bladder.ResultsThe NICE CGs were deemed to be of the highest quality (overall score of 92%). NICE were the only guidelines to systematically incorporate cost‐effectiveness research into their recommendations. The EAU CGs received an overall score of 83% and the ICI CGs achieved the lowest overall score (75%). The highest scoring domain among all the CGs was scope purpose (86%) and the lowest scoring domain was applicability (69%). All guidelines were recommended for use (mostly with some modifications).ConclusionsAll CGs had their inherent advantages and disadvantages, though all were still deemed to be of high quality. Incorporating cost‐effectiveness research would be near impossible for guidelines with a broad‐country remit. Incorporating the AGREE II instrument in the development of CGs and better collaboration between the ICI, NICE, and EAU could improve the quality, and consistency between NLUTD CGs and ultimately improve health outcomes for this important patient group.