bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vibration perception threshold for sight‐threatening retinopathy screening in type 2 diabetic outpatients
Authors: Shen Jing , Hu Yanyun , Liu Fang , Zeng Hui , Li Lianxi , Zhao Jun , Zhao Jungong , Zheng Taishan , Lu Huijuan , Lu Fengdi , Bao Yuqian , Jia Weiping 
Published: May 2013

AbstractObjectiveWe investigated the relationship between vibration perception threshold and diabetic retinopathy and verified the screening value of vibration perception threshold for severe diabetic retinopathy.MethodsA total of 955 patients with type 2 diabetes were recruited and divided into three groups according to their fundus oculi photography results: no diabetic retinopathy (n = 654, 68.48%), non‐sight‐threatening diabetic retinopathy (n = 189, 19.79%) and sight‐threatening diabetic retinopathy (n = 112, 11.73%). Their clinical and biochemical characteristics, vibration perception threshold and the diabetic retinopathy grades were detected and compared.ResultsThere were significant differences in diabetes duration and blood glucose levels among three groups (all p < 0.05). The values of vibration perception threshold increased with the rising severity of retinopathy, and the vibration perception threshold level of sight‐threatening diabetic retinopathy group was significantly higher than both non‐sight‐threatening diabetic retinopathy and no diabetic retinopathy groups (both p < 0.01). The prevalence of sight‐threatening diabetic retinopathy in vibration perception threshold >25 V group was significantly higher than those in 16–24 V group (p < 0.01). The severity of diabetic retinopathy was positively associated with diabetes duration, blood glucose indexes and vibration perception threshold (all p < 0.01). Multiple stepwise regression analysis proved that glycosylated haemoglobin (β = 0.385, p = 0.000), diabetes duration (β = 0.275, p = 0.000) and vibration perception threshold (β = 0.180, p = 0.015) were independent risk factors for diabetic retinopathy. Receiver operating characteristic analysis further revealed that vibration perception threshold higher than 18 V was the optimal cut point for reflecting high risk of sight‐threatening diabetic retinopathy (odds ratio = 4.20, 95% confidence interval = 2.67–6.59).ConclusionThere was a close association between vibration perception threshold and the severity of diabetic retinopathy. vibration perception threshold was a potential screening method for diabetic retinopathy, and its optimal cut‐off for prompting high risk of sight‐threatening retinopathy was 18 V. Copyright © 2013 John Wiley & Sons, Ltd.
Maternal and environmental influences on egg size and juvenile life‐history traits in Pacific salmon
Authors: Braun Douglas C. , Patterson David A. , Reynolds John D. 
Published: May 2013

AbstractLife‐history traits such as fecundity and offspring size are shaped by investment trade‐offs faced by mothers and mediated by environmental conditions. We use a 21‐year time series for three populations of wild sockeye salmon (Oncorhynchus nerka) to test predictions for such trade‐offs and responses to conditions faced by females during migration, and offspring during incubation. In years when their 1100 km upstream migration was challenged by high water discharges, females that reached spawning streams had invested less in gonads by producing smaller but not fewer eggs. These smaller eggs produced lighter juveniles, and this effect was further amplified in years when the incubation water was warm. This latter result suggests that there should be selection for larger eggs to compensate in populations that consistently experience warm incubation temperatures. A comparison among 16 populations, with matching migration and rearing environments but different incubation environments (i.e., separate spawning streams), confirmed this prediction; smaller females produced larger eggs for their size in warmer creeks. Taken together, these results reveal how maternal phenotype and environmental conditions can shape patterns of reproductive investment and consequently juvenile fitness‐related traits within and among populations.
Hydrological impact of war‐induced deforestation in the Mekong Basin
Authors: Lacombe Guillaume , Pierret Alain 
Published: May 2013

ABSTRACTThe Vietnam War played a decisive role in the pre‐1990s deforestation of the lower Mekong Basin, which in turn likely influenced regional broad‐scale hydrology. This note presents and discusses new analyses that strengthen this thesis. Although concurrent overestimation of discharge and underestimation of rainfall, a couple of years after bombing climaxed in the early 1970s, could theoretically explain the sharp rise in water yield previously attributed to bomb‐induced deforestation, new observations suggest that bombing has durably modified the landscape: by 2002, degraded forests still largely overlapped with areas heavily bombed 30 years earlier. This corroborates observed long‐term hydrological changes and suggests that warfare‐induced deforestation has more profound and durable hydrological effects than previously thought. Copyright © 2013 John Wiley & Sons, Ltd.
Pentaglycine–NiII Complex: From Kinetics to Structure
Authors: Gaisin Zeev , Gellerman Gary , Meyerstein Dan 
Published: May 2013

AbstractBinding NiII to the terminal amine of a peptide depresses totally its nucleophilic character as measured by the rate constant of the reaction of the peptide with 4‐nitrophenyl acetate. The structure of NiII(GGGGG) in aqueous solutions was determined by this technique. The results indicate that the ratio of complexes in which the nickel is bound to four deprotonated peptide nitrogen atoms to those in which the nickel is bound to the terminal amine and three deprotonated peptide nitrogen atoms increases as the pH increases. At pH 9.0, this ratio is approximately 1.
A Luminescent Material: La3Cl(CN2)O3 Doped with Eu3+ or Tb3+ Ions
Authors: Kubus Mariusz , Enseling David , Jüstel Thomas , Meyer H.‐Jürgen 
Published: May 2013

AbstractThe new carbodiimide compound La3Cl(CN2)O3 was obtained by a solid‐state metathesis reaction from LaOCl and Li2(CN2) at 750 °C in a fused tube. Differential scanning calorimetry of the reaction mixture was performed. The crystal structure of La3Cl(CN2)O3 was determined by single‐crystal X‐ray diffraction studies (space group Cmcm, No. 63). The luminescent properties of the Eu3+‐ and Tb3+‐doped compounds are reported.
Total Synthesis of Neo‐Tanshinlactones through a Cascade Benzannulation‐Lactonization as the Key Step
Authors: Ghosh Ketaki , Karmakar Raju , Mal Dipakranjan 
Published: May 2013

AbstractThe cascade annulation‐lactonization of phthalides with α‐carboxyfurylacrylates in the presence of lithium hexamethyldisilazide (LiHMDS) provides both convergent and semiconvergent regioselective syntheses of neo‐tanshinlactones in moderate yields. This methodology also offers an avenue for the direct syntheses of hitherto unreported 6‐alkoxycarbonyl‐substituted neo‐tanshinlactones and their heterocyclic analogues. A new synthesis of 4‐alkyl phthalides was developed on the basis of a combination of a Duff reaction and Fürstner cross‐coupling.
Structural Studies of the O‐Acetyl‐Containing O‐Antigen from a Shigella flexneri Serotype 6 Strain and Synthesis of Oligo­saccharide Fragments Thereof
Authors: Chassagne Pierre , Fontana Carolina , Guerreiro Catherine , Gauthier, Charles , Phalipon Armelle , Widmalm Göran , Mulard Laurence A. 
Published: May 2013

AbstractExtensive analysis by NMR spectroscopy of the delipidated lipopolysaccharide of Shigella flexneri serotype 6 strain MDC 2924‐71 confirmed the most recently reported structure of the O‐antigen repeating unit as {→4)‐β‐D‐GalpA‐(1→3)‐β‐D‐GalpNAc‐(1→2)‐α‐L‐Rhap3Ac/4Ac‐(1→2)‐α‐L‐Rhap‐(1→}, and revealed the non‐stoichiometric acetylation at O‐3C/4C. Input from the CASPER program helped to ascertain the fine distribution of the three possible patterns of O‐acetylation. The non‐O‐acetylated repeating unit (ABCD) corresponded to about 2/3 of the population, while 1/4 was acetylated at O‐3C (3AcCDAB), and 1/10 at O‐4C (4AcCDAB). Di‐ to tetrasaccharides with a GalpA residue (A) at their reducing end were synthesized as their propyl glycosides following a multistep linear strategy relying on late‐stage acetylation at O‐3C. Thus, the 3C‐O‐acetylated and non‐O‐acetylated targets were synthesized from common protected intermediates. Rhamnosylation was most efficiently achieved by using imidate donors, including at O‐4 of a benzyl galacturonate acceptor. In contrast, a thiophenyl 2‐deoxy‐2‐trichloroacetamido‐D‐galactopyranoside precursor was preferred for chain elongation involving residue B. Final Pd/C‐mediated deprotection ensured O‐acetyl stability. All of the target molecules represent parts of the O‐antigen of S. flexneri 6, a prevalent serotype. Non‐O‐acetylated oligosaccharides are also fragments of the Escherichia coli O147 O‐antigen.
Chronic toxicity of nickel-spiked freshwater sediments: Variation in toxicity among eight invertebrate taxa and eight sediments
Authors: Besser John M. , Brumbaugh William G. , Ingersoll Christopher G. , Ivey Chris D. , Kunz James L. , Kemble Nile E. , Schlekat Christian E. , Garman Emily Rogevich 
Published: May 2013

Abstract

This study evaluated the chronic toxicity of Ni-spiked freshwater sediments to benthic invertebrates. A 2-step spiking procedure (spiking and sediment dilution) and a 2-stage equilibration period (10 wk anaerobic and 1 wk aerobic) were used to spike 8 freshwater sediments with wide ranges of acid-volatile sulfide (AVS; 0.94–38 µmol/g) and total organic carbon (TOC; 0.42–10%). Chronic sediment toxicity tests were conducted with 8 invertebrates (Hyalella azteca, Gammarus pseudolimnaeus, Chironomus riparius, Chironomus dilutus, Hexagenia sp., Lumbriculus variegatus, Tubifex tubifex, and Lampsilis siliquoidea) in 2 spiked sediments. Nickel toxicity thresholds estimated from species-sensitivity distributions were 97 µg/g and 752 µg/g (total recoverable Ni; dry wt basis) for sediments with low and high concentrations of AVS and TOC, respectively. Sensitive species were tested with 6 additional sediments. The 20% effect concentrations (EC20s) for Hyalella and Gammarus, but not Hexagenia, were consistent with US Environmental Protection Agency benchmarks based on Ni in porewater and in simultaneously extracted metals (SEM) normalized to AVS and TOC. For Hexagenia, sediment EC20s increased at less than an equimolar basis with increased AVS, and toxicity occurred in several sediments with Ni concentrations in SEM less than AVS. The authors hypothesize that circulation of oxygenated water by Hexagenia led to oxidation of AVS in burrows, creating microenvironments with high Ni exposure. Despite these unexpected results, a strong relationship between Hexagenia EC20s and AVS could provide a basis for conservative site-specific sediment quality guidelines for Ni. Environ Toxicol Chem 2013;32:2495–2506. © 2013 SETAC
Electrochemical Deposition of Highly Dispersed Palladium Nanoparticles on Nafion‐Graphene Film in Presence of Ferrous Ions for Ethanol Electrooxidation
Authors: Shendage S. S. , Patil U. B. , Nagarkar J. M. 
Published: May 2013

AbstractAn efficient method was developed to produce highly dispersed Pd nano particles (NPs), supported on Nafion‐graphene film by electrochemical deposition at constant potential in presence of ferrous ions. The Fe2+ ions govern the size, shape and morphology of Pd NPs. The as‐prepared catalyst was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD). It was obeserved from TEM that the mean diameter of electrodeposited Pd NPs was 6.4 ± 1.3 nm with narrow diameter range from 4 to 10 nm. The electrocatalytic performance of the Pd NPs deposited on Nafion‐graphene (Nf‐G) catalyst was studied by cyclic voltametry (CV) and chronoamperometric measurements. The highly dispersed Pd NPs on Nf‐G film were obtained in presence of Fe2+ ions. This alters electrochemical active surface area and hence catalytic activity of Pd NPs. The prepared Pd/Nf‐G catalyst exhibit highest tolerance to the intermediate poisoning species (ratio If/Ib = 2.2). The as‐obtained catalyst shows an efficient electrocatalytic activity and good stability for ethanol oxidation in alkaline medium.
Factors associated with caregiver readiness to use nonpharmacologic strategies to manage dementia‐related behavioral symptoms
Authors: Gitlin Laura N. , Rose Karen 
Published: May 2013

BackgroundNonpharmacologic strategies to manage dementia‐related behavioral symptoms depend upon caregiver implementation. Caregivers may vary in readiness to use strategies. We examined characteristics associated with readiness, extent readiness changed during intervention, and predictors of change in readiness.MethodsData came from a randomized trial involving 119 caregivers in a nonpharmacologic intervention for managing behavioral symptoms. Baseline measures included caregiver, patient, and treatment‐related factors. At initial (2 weeks from baseline) and final (16 weeks) intervention sessions, interventionists rated caregiver readiness as pre‐action (precontemplation = 1; contemplation = 2; preparation = 3) or action (= 4). Ordinal logistic regression identified baseline characteristics associated with initial readiness. Mc Nemar–Bowker test of symmetry described change in readiness; binary logistic regression identified baseline predictors of change in readiness (initial to final sessions). One‐way multivariate analysis of variance identified treatment factors (dose/intensity, number of strategies used, perceived benefits, and therapeutic engagement) associated with change in readiness.ResultsAt initial intervention session, 67.2% (N = 80) of caregivers were in pre‐action and 32.8% (N = 39) in action. Initial high readiness was associated with better caregiver mood, less financial difficulty, lower patient cognition, and more behavioral symptoms. By final session, 72% (N = 79) were in action and 28% (N = 31) in pre‐action; caregivers with less financial difficulty improved in readiness (B = −0.70, p = 0.017); those in action were more therapeutically engaged (F[2,107] = 3.61, p = 0.030) and perceived greater intervention benefits (F[2, 88] = 6.06, p = 0.003).ConclusionWhereas patient and caregiver‐related factors were associated with initial readiness, financial stability, therapeutic engagement, and perceived benefits enhanced probability of change. Understanding caregiver readiness and factors associated with its change may be important considerations in nonpharmacologic interventions. Copyright © 2013 John Wiley & Sons, Ltd.
Observation of multiple sub‐cavities adjacent to single separatrix
Authors: Wang Rongsheng , Du Aimin , Nakamura Rumi , Lu Quanming , Khotyaintsev Yuri V. , Volwerk Martin , Zhang Tielong , Kronberg E. A. , Daly P. W. , Fazakerley Andrew N. 
Published: May 2013

AbstractWe investigate a direct south‐north crossing of a reconnection ion diffusion region in the magnetotail. During this crossing, multiple electron density dips with a further density decrease within the cavity, called sub‐cavities, adjacent to the northern separatrix are observed. The correlation between electron density sub‐cavities and strong electric field fluctuations is obvious. Within one of the sub‐cavities, a series of very strong oscillating perpendicular electric field and patchy parallel electric field are observed. The parallel electric field is nearly unipolar and directs away from X line. In the same region, inflow electrons with energy up to 100 keV are injected into the X line. Based on the observations, we conclude that the high‐energy inflowing electrons are accelerated by the patchy parallel electric field. Namely, electrons have been effectively accelerated while they are flowing into the X line along the separatrix. The observations indicate that the electron acceleration region is widely larger than the predicted electron diffusion region in the classical Hall magnetic reconnection model.
Prediction of stream‐flow regime using ecological classification zones
Authors: Trubilowicz Joel W. , Moore R. D. , Buttle J. M. 
Published: May 2013

AbstractHydrologic classification is useful for data organization, transfer of model parameters and estimation of hydrologic sensitivity to disturbance and climatic change. Stream‐flow regime has frequently been used as a basis for classification, typically by mapping regimes defined by stream‐flow data from a gauging network. As an alternative, we hypothesized that ecological classification systems can predict stream‐flow regime because they are based on the same characteristics that control run‐off generation (soils, climate and topography). A multivariate regression tree (MRT) was used to relate stream‐flow regime to the fractional coverages of the Biogeoclimatic Ecological Classification (BEC) zones within the catchment for gauged streams in British Columbia, Canada. Although the MRT identified a realistic set of regimes, only a small number of BEC zones were used as predictors, reflecting bias in the gauging network. To avoid this bias, we used a water balance model to compute mean monthly stream flow for 932 ungauged basins in British Columbia that were generated with areas between 10 and 1000 km2; these monthly stream flows were used to train an MRT model based on BEC zone coverages. This model predicted the regime at gauged basins nearly as accurately as the water balance model for pluvial, nival and glacier‐supported nival regimes. Difficulties occurred in smaller basins and in specific regions where the local BEC zones were not included as predictors. Coastal hybrid nivo–pluvial regimes were poorly predicted. With further development, ecological classification systems could have great value as a tool for hydrologic classification for both research and operational applications. Copyright © 2013 John Wiley & Sons, Ltd.
Validation of the Flood‐PROOFS probabilistic forecasting system
Authors: Laiolo P. , Gabellani S. , Rebora N. , Rudari R. , Ferraris L. , Ratto S. , Stevenin H. , Cauduro M. 
Published: May 2013

AbstractProbabilistic hydrometeorological forecasting systems are becoming more and more an operational tool used by civil protection centres for issuing flood alerts. One of the most important requests of decision makers is related to the reliability of such systems and to the validation of their predictive performances. For these reasons, this work is devoted to the validation of a probabilistic flood forecasting system called Flood‐PRObabilistic Operational Forecasting System (Flood‐PROOFS). The system is operational in real time, since 2008, in Valle d'Aosta, an alpine Region of northern Italy. It is used by the Civil Protection regional service to issue warnings and by the local water company to protect its facilities. The system manages and uses both real‐time meteorological and satellite data and real‐time data on the operation of the control structures in dam and river, managed by the water company. It has proven a useful tool for flood forecasting and for managing complex situations, facilitating the dialogue between civil protection and the water company during crisis periods.The system uses both a limited area model forecast and a forecast issued by regional expert meteorologists. The main outputs are deterministic and probabilistic discharge forecasts in different outlet areas of the river network.The performance of the system has been evaluated on a 25 months period with different statistical methods such as Brier score and Rank histograms. The results highlight good performances of the system as support system for emitting warnings, but there is a lack of statistics especially for huge discharge events. Copyright © 2013 John Wiley & Sons, Ltd.
Water source dynamics of high Arctic river basins
Authors: Blaen Phillip J. , Hannah David M. , Brown Lee E. , Milner Alexander M. 
Published: May 2013

AbstractArctic river basins are amongst the most vulnerable to climate change. However, there is currently limited knowledge of the hydrological processes that govern flow dynamics in Arctic river basins. We address this research gap using natural hydrochemical and isotopic tracers to identify water sources that contributed to runoff in river basins spanning a gradient of glacierization (0–61%) in Svalbard during summer 2010 and 2011. Spatially distinct hydrological processes operating over diurnal, weekly and seasonal timescales were characterized by river hydrochemistry and isotopic composition. Two conceptual water sources (‘meltwater’ and ‘groundwater’) were identified and used as a basis for end‐member mixing analyses to assess seasonal and year‐to‐year variability in water source dynamics. In glacier‐fed rivers, meltwater dominated flows at all sites (typically >80%) with the highest contributions observed at the beginning of each study period in early July when snow cover was most extensive. Rivers in non‐glacierized basins were sourced initially from snowmelt but became increasingly dependent on groundwater inputs (up to 100% of total flow volume) by late summer. These hydrological changes were attributed to the depletion of snowpacks and enhanced soil water storage capacity as the active layer expanded throughout each melt season. These findings provide insight into the processes that underpin water source dynamics in Arctic river systems and potential future changes in Arctic hydrology that might be expected under a changing climate. Copyright © 2013 John Wiley & Sons, Ltd.
Modelling the effects of land use and climate changes on hydrology in the Ursern Valley, Switzerland
Authors: Alaoui A. , Willimann E. , Jasper K. , Felder G. , Herger F. , Magnusson J. , Weingartner R. 
Published: May 2013

AbstractWhile many studies have been conducted in mountainous catchments to examine the impact of climate change on hydrology, the interactions between climate changes and land use components have largely unknown impacts on hydrology in alpine regions. They need to be given special attention in order to devise possible strategies concerning general development in these regions. Thus, the main aim was to examine the impact of land use (i.e. bushland expansion) and climate changes (i.e. increase of temperature) on hydrology by model simulations. For this purpose, the physically based WaSiM‐ETH model was applied to the catchment of Ursern Valley in the central Alps (191 km2) over the period of 1983−2005. Modelling results showed that the reduction of the mean monthly discharge during the summer period is due primarily to the retreat of snow discharge in time and secondarily to the reduction in the glacier surface area together with its retreat in time, rather than the increase in the evapotranspiration due to the expansion of the “green alder” on the expense of grassland. The significant decrease in summer discharge during July, August and September shows a change in the regime from b‐glacio‐nival to nivo‐glacial. These changes are confirmed by the modeling results that attest to a temporal shift in snowmelt and glacier discharge towards earlier in the year: March, April and May for snowmelt and May and June for glacier discharge. It is expected that the yearly total discharge due to the land use changes will be reduced by 0.6% in the near future, whereas, it will be reduced by about 5% if climate change is also taken into account. Copyright © 2013 John Wiley & Sons, Ltd.