bluuebunny/crossref_metadata_2025_split huggingface dataset:
Covalent drug immobilization in poly(ester amide) nanoparticles for controlled release
Authors: Moustafa Amira , Abd Rabo Moustafa Mahmoud M. , Zilinskas Gregory J. , Gillies Elizabeth R. 
Published: September 2015

AbstractThe use of polymeric nanoparticles to encapsulate and deliver drug molecules is a promising approach for improving drug properties such as water dispersibility, pharmacokinetics, and selectivity for the in vivo target. Described here is the development of poly(ester amide) (PEA) nanoparticles prepared from PEAs with pendant functional groups that allow for covalent conjugation of the drugs in order to mitigate the undesirable burst release of drug, commonly observed for nanoparticle‐based drug delivery systems. Parameters including the surfactant and PEA concentration in an emulsification‐evaporation procedure were studied in order to determine conditions for preparing particles with diameters < 200 nm. A hydroxyl‐functionalized rhodamine derivative, as a model drug, was then conjugated to a PEA having pendant carboxylic acid groups to afford a PEA‐rhodamine conjugate with the dye covalently attached by ester linkages. The emulsification‐evaporation procedure was used to prepare nanoparticles from this conjugate and these particles were found to release the dye much more slowly and without a burst effect, in comparison with analogous nanoparticles having the rhodamine physically encapsulated. The same approach was applied to the anti‐cancer drug floxuridine and the resulting nanoparticles also afforded sustained drug release. This work suggests the promise of PEAs with pendant functional groups for providing nanoparticle‐based drug delivery vehicles with slow and sustained drug release.
Mechanochromic Fibers with Structural Color
Authors: Li Houpu , Sun Xuemei , Peng Huisheng 
Published: September 2015

AbstractResponsive photonic crystals have been widely developed to realize tunable structural colors by manipulating the flow of light. Among them, mechanochromic photonic crystals attract increasing attention due to the easy operation, high safety and broad applications. Recently, mechanochromic photonic crystal fibers were proposed to satisfy the booming wearable smart textile market. In this Concept, the fundamental mechanism, fabrication, and recent progress on mechanochromic photonic crystals, especially in fiber shape, are summarized to represent a new direction in sensing and displaying.
How Sensitive is the Amide I Vibration of the Polypeptide Backbone to Electric Fields?
Authors: Oh Kwang‐Im , Fiorin Giacomo , Gai Feng 
Published: September 2015

AbstractSite‐selective isotopic labeling of amide carbonyls offers a nonperturbative means to introduce a localized infrared probe into proteins. Although this strategy has been widely used to investigate various biological questions, the dependence of the underlying amide I vibrational frequency on electric fields (or Stark tuning rate) has not been fully determined, which prevents it from being used in a quantitative manner in certain applications. Herein, through the use of experiments and molecular dynamics simulations, the Stark tuning rate of the amide I vibration of an isotopically labeled backbone carbonyl in a transmembrane α‐helix is determined to be approximately 1.4 cm−1/(MV/cm). This result provides a quantitative basis for using this vibrational model to assess local electric fields in proteins, among other applications. For instance, by using this value, we are able to show that the backbone region of a dipeptide has a surprisingly low dielectric constant.
Bandgap‐ and Radial‐Position‐Dependent Mn‐Doped Zn–Cu–In–S/ZnS Core/Shell Nanocrystals
Authors: Peng Lucheng , Huang Keke , Zhang Zhuolei , Zhang Ying , Shi Zhan , Xie Renguo , Yang Wensheng 
Published: September 2015

AbstractThis paper presents a mechanistic study on the doping of Zn–Cu–In–S/ZnS core/shell quantum dots (QDs) with Mn by changing the Zn–Cu–In–S QD bandgap and dopant position inside the samples (Zn–Cu–In–S core and ZnS shell). Results show that for the Mn:Zn–Cu–In–S/ZnS system, a Mn‐doped emission can be obtained when the bandgap value of the QDs is larger than the energy of Mn‐doped emission. Conversely, a bandgap emission is only observed for the doped system when the bandgap value of QDs is smaller than the energy gap of the Mn‐doped emission. In the Zn–Cu–In–S/Mn:ZnS systems, doped QDs show dual emissions, consisting of bandgap and Mn dopant emissions, instead of one emission band when the value of the host bandgap is larger than the energy of the Mn‐doped emission. These findings indicate that the emission from Mn‐doped Zn–Cu–In–S/ZnS core/shell QDs depends on the bandgap of the QDs and the dopant position inside the core/shell material. The critical bandgap of the host materials is estimated to have the same value as the energy of the Mn d–d transition. Subsequently, the mechanism of photoluminescence properties of the Mn:Zn–Cu–In–S/ZnS and Zn–Cu–In–S/Mn:ZnS core/shell QD systems is proposed. Control experiments are then carried out by preparing Mn‐doped Zn(Cu)–In–S QDs with various bandgaps, and the results confirm the reliability of the suggested mechanism. Therefore, the proposed mechanism can aid the design and synthesis of novel host materials in fabricating doped QDs.
DNA Microenvironment Monitored by Controlling Redox Blinking
Authors: Kawai Kiyohiko , Higashiguchi Kenji , Maruyama Atsushi , Majima Tetsuro 
Published: September 2015

AbstractThe rate of a bimolecular reaction between a fluorophore and a freely diffusing molecule in the solvent depends on the accessibility of the fluorophore for collision with the molecule. We previously reported that the observation of blinking, caused by the formation of R6G in the excited triplet state (3R6G*) and its quenching reaction with O2, allowed us to monitor the DNA conformational changes between a duplex and a hairpin. However, the small molecular size of O2 hampered sensitive monitoring of the microenvironment changes around R6G. In this study, we control redox blinking by adding a reductant ascorbic acid 2‐phosphate (VcP), which converts 3R6G* into the radical anion form R6G.−, and by adding a bulky oxidant FeDTPA. The bimolecular electron‐transfer rate between R6G.− and bulky FeDTPA was more strongly affected by microenvironment changes around R6G, compared with that between 3R6G* and the smaller O2. This allowed us to monitor subtle DNA conformational changes caused by a single different nucleotide.
Retracted: High‐speed FSK modulator using switched‐capacitor resonators
Authors: Salehi Mohsen 
Published: September 2015

SummaryThe above article, published online on 30 September 2015 in Wiley Online Library (http://www.onlinelibrary.wiley.com), has been retracted by agreement between the journal Editor in Chief, Ángel Rodríguez‐Vázquez, and John Wiley & Sons, Ltd. Following an investigation by the institution of the author, the retraction has been agreed because a co‐author was not informed of the submission and did not provide consent for it to proceed. In addition, the co‐author was not acknowledged in the manuscript itself. The article is to be retracted at the request of the co‐author.ReferenceSalehi M. (2015) . Int. J. Circ. Theor. Appl., doi:10.1002/cta.2157.
Two base station location techniques with adjusted measurements in circular scattering environments
Authors: Wu Shixun , Xu Dengyuan , Tan Jin , Xu Kai , Wang Honggang 
Published: September 2015

SummaryIn circular scattering environments, novel location techniques with only two base stations (BSs) are proposed in this paper. The proposed techniques estimate the true or line‐of‐sight ranges and angle based on non‐line‐of‐sight range and angle measurements. Three new variables are introduced when range measurements and angle measurement are available from two BSs and the serving BS, respectively. Bounds and relationships between the three variables are extracted from the geometry of the cell layout with the unknown and known scattering radius conditions, respectively. Our aim is to obtain the estimation of three new variables and then the hybrid line of position technique with the adjusted ranges, and angle is utilized to obtain the position estimation of a mobile station. In order to obtain the estimation of three new variables, a new nonlinear objective function is built to form the constrained nonlinear optimization and solved by the existing optimization algorithms. However, because of the nonconvex objective function, the optimization algorithm may converge to the local optimum and lead to bad performance. Thus, a heuristic search algorithm is proposed by averaging all the potential point. Simulation results show that the proposed techniques outperform conventional hybrid techniques. Copyright © 2015 John Wiley & Sons, Ltd.
Which heart failure patients profit from natriuretic peptide guided therapy? A meta‐analysis from individual patient data of randomized trials
Authors: Brunner‐La Rocca Hans‐Peter , Eurlings Luc , Richards A. Mark , Januzzi James L. , Pfisterer Matthias E. , Dahlström Ulf , Pinto Yigal M. , Karlström Patric , Erntell Hans , Berger Rudolf , Persson Hans , O'Connor Christopher M. , Moertl Deddo , Gaggin Hanna K. , Frampton Christopher M. , Nicholls M. Gary , Troughton Richard W. 
Published: September 2015

AimsPrevious analyses suggest that heart failure (HF) therapy guided by (N‐terminal pro‐)brain natriuretic peptide (NT‐proBNP) might be dependent on left ventricular ejection fraction, age and co‐morbidities, but the reasons remain unclear.Methods and resultsTo determine interactions between (NT‐pro)BNP‐guided therapy and HF with reduced [ejection fraction (EF) ≤45%; HF with reduced EF (HFrEF), n = 1731] vs. preserved EF [EF > 45%; HF with preserved EF (HFpEF), n = 301] and co‐morbidities (hypertension, renal failure, chronic obstructive pulmonary disease, diabetes, cerebrovascular insult, peripheral vascular disease) on outcome, individual patient data (n = 2137) from eight NT‐proBNP guidance trials were analysed using Cox‐regression with multiplicative interaction terms. Endpoints were mortality and admission because of HF. Whereas in HFrEF patients (NT‐pro)BNP‐guided compared with symptom‐guided therapy resulted in lower mortality [hazard ratio (HR) = 0.78, 95% confidence interval (CI) 0.62–0.97, P = 0.03] and fewer HF admissions (HR = 0.80, 95% CI 0.67–0.97, P = 0.02), no such effect was seen in HFpEF (mortality: HR = 1.22, 95% CI 0.76–1.96, P = 0.41; HF admissions HR = 1.01, 95% CI 0.67–1.53, P = 0.97; interactions P < 0.02). Age (74 ± 11 years) interacted with treatment strategy allocation independently of EF regarding mortality (P = 0.02), but not HF admission (P = 0.54). The interaction of age and mortality was explained by the interaction of treatment strategy allocation with co‐morbidities. In HFpEF, renal failure provided strongest interaction (P < 0.01; increased risk of (NT‐pro)BNP‐guided therapy if renal failure present), whereas in HFrEF patients, the presence of at least two of the following co‐morbidities provided strongest interaction (P < 0.01; (NT‐pro)BNP‐guided therapy beneficial only if none or one of chronic obstructive pulmonary disease, diabetes, cardiovascular insult, or peripheral vascular disease present). (NT‐pro)BNP‐guided therapy was harmful in HFpEF patients without hypertension (P = 0.02).ConclusionThe benefits of therapy guided by (NT‐pro)BNP were present in HFrEF only. Co‐morbidities seem to influence the response to (NT‐pro)BNP‐guided therapy and may explain the lower efficacy of this approach in elderly patients.
Structural Insights into the Binding of Sugar Receptors (Lectins) to a Synthetic Tricyclic Tn Mimetic and Its Glycopeptide Version
Authors: Ardá Ana , Bosco Rosa , Sastre Javier , Cañada F. Javier , André Sabine , Gabius Hans‐Joachim , Richichi Barbara , Jiménez‐Barbero Jesus , Nativi Cristina 
Published: September 2015

AbstractCycloadduct 1 is a conformationally constrained mimetic of the tumor‐associated Tn antigen. It maintains the 4C1 conformation and the α‐O‐glycosidic linkage of the natural epitopes. Due to its tricyclic structure, the anomeric linkage is constrained and its conformation “frozen”. Using saturation transfer difference NMR spectroscopy experiments, epitope mapping for binding by three lectins [i.e., from Erythrina cristagalli (ECL), human macrophages (MGL), and from Helix pomatia (HPA)] was carried out. Striking differences in the epitope viewed from the ligand's perspective were revealed by this comparison. Evidently, the structural change around the C‐2 position has a major impact, if the contact pattern to the ligand is not mostly restricted to galacto configuration with the axial hydroxyl group at C‐4, in combination with C‐3/C‐6. These measurements thus provide insights into actual contacts, which help predict applicability as an inhibitor for distinct lectins, and as an elicitor of specific antibodies.
Deciphering mechanisms of malathion toxicity under pulse exposure of the freshwater cladoceran Daphnia magna
Authors: Trac Lam Ngoc , Andersen Ole , Palmqvist Annemette 
Published: September 2015

Abstract

The organophosphate pesticide (OP) malathion is highly toxic to freshwater invertebrates, including the cladoceran Daphnia magna, a widely used test organism in ecotoxicology. To assess whether toxic effects of malathion are driven primarily by exposure concentration or exposure duration, D. magna was pulse exposed to equivalent integrated doses (duration × concentration): 3 h × 16 μg/L, 24 h × 2 μg/L, and 48 h × 1 μg/L. After recovery periods of 3 h, 24 h, and 48 h, the toxicity of malathion on different biological levels in D. magna was examined by analyzing the following endpoints: survival and immobilization; enzyme activities of acetylcholinesterase (AChE), carboxylesterase (CbE), and glutathione S-transferase (GST); and AChE gene expression. The results showed no difference in survival among equivalent integrated doses. Adverse sublethal effects were driven by exposure concentration rather than pulse duration. Specifically, short pulse exposure to a high concentration of malathion resulted in more immobilized daphnids, lower AChE and CbE activities, and a higher transcript level of AChE gene compared with long pulse exposure to low concentration. The expression of the AChE gene was up-regulated, indicating a compensatory mechanism to cope with enzyme inhibition. The study shows the need for obtaining a better understanding of the processes underlying toxicity under realistic exposure scenarios, so this can be taken into account in environmental risk assessment of pesticides. Environ Toxicol Chem 2016;35:394–404. © 2015 SETAC
Pesticide determination in rose concrete and rose absolute using dispersive‐solid phase extraction followed by gas chromatography‐tandem mass spectrometry
Authors: Tascone Oriane , Roy Céline , Meierhenrich Uwe J. 
Published: September 2015

AbstractThe rose species Rosa damascena and Rosa centifolia are cultivated for their use as perfume raw materials. The solvent extract of rose petals provides the concrete that is further transformed into the absolute. Both, concrete and absolute contain a variety of organic molecules. As a result of the lack of an adequate analytical procedure and the complexity of the matrices, the accurate quantification of pesticides in concrete and absolute remains challenging. Here we describe the first analytical method to quantify 57 pesticide residues in rose concrete and 56 pesticide residues in rose absolute. The method uses a multistep dispersive‐solid phase extraction (d‐SPE) cleanup followed by injection in a gas chromatography‐tandem mass spectrometer. Sample preparation includes the extraction of analytes from the matrix using acetonitrile and a mixture of salts and a double clean‐up step using sorbents in the form of primary and secondary amines (PSA), magnesium sulphate, C18 and graphitized carbon black (GCB). Two fortification levels, 0.025 to 0.15 and 0.5 mg/kg, were assessed. For 56 pesticides, the obtained recoveries were within the range of 70% to 120 % with a relative standard deviation (RSD) lower than 20% at each spiked level. The validation parameters proved that the developed method can be used for the quantification of 57 pesticide residues in rose concrete and 56 pesticide residues in rose absolute with a limit of quantification (LOQ) ranging from 0.025 to 0.1 mg/kg in concrete and from 0.05 to 0.15 mg/kg in absolute, depending on the active substance. Copyright © 2015 John Wiley & Sons, Ltd.
Pain grade and sleep disturbance in older adults: evaluation the role of pain, and stress for depressed and non‐depressed individuals
Authors: Eslami Vahid , Zimmerman Molly E. , Grewal Trishdeep , Katz Mindy , Lipton Richard B. 
Published: September 2015

ObjectiveThe aim of this paper was to assess the relationship between pain and sleep in older adults taking depression, stress, and medical comorbidities into account.MethodsA cross‐sectional analysis was performed using Einstein Aging Study, a community‐based cohort study of adults aged 70 years and older. Ratings of pain intensity and interference from the Medical Outcomes Study (MOS) Short‐Form 36 were used to assign individuals to low‐pain versus high‐pain severity. Sleep disturbance was assessed using the nine‐item sleep problems index from the Medical Outcomes Study Sleep Scale. Other measures included the Geriatric Depression Scale and Perceived Stress Scale (PSS). Linear regression models were used to assess the association between pain grade and sleep disturbance adjusted for demographics, PSS, Geriatric Depression Scale, and other comorbidities.ResultsFive hundred sixty‐two eligible participants with a mean age of 78.22 years (standard deviation = 5.43) were included; 64% were women. Pain grade [β = 5.40, 95% confidence interval (CI) 2.56–8.21, p < 0.001] was associated with sleep disturbance after adjusting for demographic variables. In models including pain grade (β = 3.08, 95% CI 0.32–5.85, p = 0.03) and PSS (β = 0.57, 95% CI 0.39–0.75, p < 0.001), both were associated with sleep disturbance, although the PSS attenuated the relationship between pain and sleep by 34%. Depression, when added to previous model, was also associated with sleep (β = 2.17, 95% CI 1.48–2.85, p < 0.001) and attenuated the relationship between pain (β = 2.41, 95% CI −0.25 to 5.08, p = 0.07) and sleep by 22%. Stratified for depression, we found that pain, stress, and other medical comorbidities were significantly associated with sleep disturbance in non‐depressed individuals but not individuals with depression.ConclusionsPain, stress, and medical comorbidities are associated with sleep disturbance, especially in non‐depressed older adults.
Suicide attempts and completions in Veterans Affairs nursing home care units and long‐term care facilities: a review of root‐cause analysis reports
Authors: Mills Peter D. , Gallimore Bradley I. , Watts B. Vince , Hemphill Robin R. 
Published: September 2015

ObjectiveSuicide was the 10th leading cause of death for Americans in 2010. The suicide rate is highest among men who are aged 75 and older. The prevalence of suicidal behavior in nursing homes and long‐term care (LTC) facilities was estimated to be 1%. This study describes the systemic vulnerabilities found after suicidal behavior in LTC facilities as well as steps to decrease or mitigate the risk.MethodThis is a retrospective review of root‐cause analysis (RCA) reports of suicide attempts and completions between 1 January 2000 and 31 December 2013 in the Veterans Health Administration LTC and nursing home care units. The RCA reports of suicide attempts and completions were coded for patient demographics, method of attempt or completion, root causes, and actions developed to address the root cause.ResultsThirty‐five RCA reports were identified. The average age was 65 years, 11 had a previous suicide attempt, and the primary mental health diagnoses were depression, posttraumatic stress disorder, and schizophrenia. The primary methods of self‐harm were cutting with a sharp object, overdose, and strangulation.ConclusionsIt is recommended that all staff members are aware of the signs and risk factors for depression and suicide in this population and should systematically assess and treat mental disorders. In addition, LTC facilities should have a standard protocol for evaluating the environment for suicide hazards and use interdisciplinary teams to promote good communication about risk factors identified among patients. Finally, staff should go beyond staff education and policy to make clinical changes at the bedside. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Velocities, celerities and the basin of attraction in catchment response
Authors: Beven Keith , Davies Jess 
Published: September 2015

AbstractCatchment systems are interestingly nonlinear, but their dynamics are constrained from being unduly chaotic by mass and energy balance requirements. There have been no attempts in hydrology that we know of that have tried to map both the flow and transport dynamics of a catchment in any form of phase space. In part, this is because of the high dimensionality of the space–time patterns of response; in part because there is sufficient uncertainty about the input and output fluxes estimated by measurement that this might be expected to obscure any attractor‐like behaviour. In this study we explore the basin of the catchment attractor for the Multiple Interacting Pathway (MIPs) model that in previous papers has been shown to give good results for the small Gårdsjön catchment in Sweden. MIPs is based on particle tracking techniques and gives results for both the flow responses and for the travel and residence time responses of water in the catchment. Here it is used to provide consistent values of fluxes, total storage, travel time distributions and residence time distributions for a long simulation period. The nature of those responses in storage and input dimensions is then investigated. The results suggest that the range of behaviours is hysteretic in interesting ways and constrained by the forcing inputs, with space filling of trajectories in the basin of attraction as should be expected of a forced dissipative system. The range of behaviours exhibited defines a space that the responses of any simpler emulator model will need to span. © 2015 The Authors Hydrological Processes Published by John Wiley & Sons Ltd.
Changes in canopy transpiration of Japanese cypress and Japanese cedar plantations because of selective thinning
Authors: Tateishi Makiko , Xiang Yang , Saito Takami , Otsuki Kyoichi , Kasahara Tamao 
Published: September 2015

AbstractCanopy transpiration (Estand) is a main component of forest water cycle, and forest management including thinning affects canopy transpiration Estand, yet few studies have examined the changes in Estand. In this study, we investigated the changes in Estand after the thinning of Chamaecyparis obtusa and Cryptomeria japonica stands by 50% of their stems. The Estand was estimated using sap flow measurements by Granier‐type thermal dissipation probes. The mean stand sap flow density (JS) after thinning was as high as that before thinning in both plots. Under the same conditions of microclimate, Estand after thinning decreased by 44.0 and 21.2% for the Ch. obtusa plot and the Cr. japonica plot, respectively. The thinning reduced the sapwood area by 44.5% in the Ch. obtusa plot and 34.2% in the Cr. japonica plot. The decreases in Estand were similar to the decline in sapwood area, which indicates that the primary cause of the changes in Estand was the reduction of sapwood area. The reference canopy conductance (Gcref) after thinning was 52.7% and 75.3% lower for Ch. obtusa and Cr. japonica, respectively, whereas stomatal sensitivity to the vapour pressure deficit was similar in both periods. Thus, the changes in canopy conductance after thinning were associated with changes in Gcref, resulting in a decrease of Estand. Copyright © 2015 John Wiley & Sons, Ltd.