bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scalable synthesis and validation of PAMAM dendrimer‐N‐acetyl cysteine conjugate for potential translation
Authors: Sharma Rishi , Sharma Anjali , Kambhampati Siva P. , Reddy Rajsekar Rami , Zhang Zhi , Cleland Jeffrey L. , Kannan Sujatha , Kannan Rangaramanujam M. 
Published: April 2018

AbstractDendrimer‐N‐acetyl cysteine (D‐NAC) conjugate has shown significant promise in multiple preclinical models of brain injury and is undergoing clinical translation. D‐NAC is a generation‐4 hydroxyl‐polyamidoamine dendrimer conjugate where N‐acetyl cysteine (NAC) is covalently bound through disulfide linkages on the surface of the dendrimer. It has shown remarkable potential to selectively target and deliver NAC to activated microglia and astrocytes at the site of brain injury in several animal models, producing remarkable improvements in neurological outcomes at a fraction of the free drug dose. Here we present a highly efficient, scalable, greener, well‐defined route to the synthesis of D‐NAC, and validate the structure, stability and activity to define the benchmarks for this compound. This newly developed synthetic route has significantly reduced the synthesis time from three weeks to one week, uses industry‐friendly solvents/reagents, and involves simple purification procedures, potentially enabling efficient scale up.
Molecular and Biological Catalysts Coimmobilization on Electrode by Combining Diazonium Electrografting and Sequential Click Chemistry
Authors: Zhang Lin , Vilà Neus , Walcarius Alain , Etienne Mathieu 
Published: April 2018

AbstractA generic approach has been developed for sequential heterogeneous surface modification of electrodes. The strategy, which is applicable for a wide range of functional groups, involves two main steps. In the first one, azide‐alkene bifunctionalized electrodes are obtained by electrochemical reduction of a mixture of diazonium salts generated in situ from the corresponding 4‐azidoaniline and 4‐vinylaniline. In that way, we provide reactive sites that are available for further selective functionalization in a sequential process based on ‘click reactions’, in which subsequent immobilization of the targeted molecules is achieved by the azide‐alkyne cycloaddition Huisgen reaction and alkene‐thiol coupling. Feasibility of the method has been first demonstrated for the coimmobilization of two distinct redox moieties (cobaltocenium and ferrocene) as evidenced by cyclic voltammetry and X‐ray photoelectron spectroscopy measurements. The versatility of the sequential method has then been exploited for the coimmobilization of a molecular electrocatalyst [Cp*Rh(bpy) Cl]+ and a biological catalyst, a NAD‐dependent dehydrogenase, that were proved to act in cascade in the electroenzymatic reduction of D‐fructose to D‐sorbitol. Such simple combination of diazonium chemistry and robust chemical reactions (‘click chemistry’) is promising for the environmentally friendly heterogeneous modification of electrodes with multiple chemical and biological catalysts.
Influence of Marangoni stress on the variation in number of coalescence cascade stages
Authors: Haldar Krishnayan , Chakraborty Samarshi , Chakraborty Sudipto 
Published: April 2018

AbstractThe present work is an experimental and theoretical study on surfactant‐laden liquid drop impact on a liquid pool. When the drop breaks into a secondary droplet after impinging, then it is called partial coalescence. If this happens successively in self‐similar manner then it is called coalescence cascade. Three different types of surfactants, cationic, anionic, and non‐ionic, are used as drop fluid and water as the liquid pool. Here we report how the surfactant types and concentrations affect the number of stages in coalescence cascade. The experimental outcome revealed that the number of stages in cascade decreases with increasing surfactant concentration. Also, we determine that drop viscosity, density, and size play a crucial role while comparing the stages of cascade among three types of surfactants. We also perform scaling analysis to determine the contribution of inertial and surface forces in the cascade. A theoretical analysis using lubrication approximation has also been carried out to justify the experimental observations. The coalescence process is actually triggered by the drainage of entrapped air between the drop and pool. The theoretical analysis reveals that the faster air drainage rate and acceleration induces a strong Marangoni stress for necking and quick pinch off. Finally, it is shown that Marangoni flow, originated due to the surface tension difference between the drop and pool, is responsible for partial coalescence and a number of coalescence stages in cascade.
The use of indirectly bonded 13C‐1H (INCH) shift correlation spectra for ab initio structure elucidation of natural products and other complex organic compounds; A personal and historical perspective
Authors: Reynolds William F. 
Published: April 2018

AbstractThis article reviews the use of long‐range shift correlation spectra for structure elucidation of natural products and other complex organic compounds from the early 1980's to the present. Much of it is written from the personal viewpoint of someone who has been involved in this area of research since its earliest days. The first section covers the early use of long‐range correlation spectra in the 1980's. The second section covers the development of specialized pulse sequences for this type of acquisition. It begins with three 13C‐detected sequences, followed by heteronuclear multiple bond correlation (HMBC) and some modified versions of HMBC and, finally, longer range correlation sequences based on the heteronuclear single quantum multiple bond correlation sequence. The third section covers various sequences designed to distinguish between 2‐bond and longer range 13C‐1H correlations. Unfortunately, none of these can make this distinction for non‐protonated carbons. Only the 1,1‐ADEQUATE sequence can make this distinction but its very low sensitivity limits its usefulness. The next section focuses on ways of avoiding getting incorrect structures of organic compounds, an ongoing problem in natural product research. The last section includes likely short‐term developments and possible long‐term developments in NMR methodology that would be beneficial for small molecule structure elucidation.
Solid‐state NMR studies of chemical exchange in ion conductors for alternative energy applications
Authors: Smiley Danielle L. , Goward Gillian R. 
Published: April 2018

AbstractHere we describe the selective inversion methodology for quantifying the rates of site‐specific ion exchange in materials such as lithium ion battery cathode frameworks. This strategy is shown to be robust in the presence of paramagnetic centers and viable and efficient for the evaluation of hopping rates, in spite of varying initial conditions for the NMR experiment. This is contrasted with 2D EXSY methodology, and selective inversion is shown to be preferable for a number of reasons articulated herein. Work in this area in our group was guided by insights into chemical exchange processes provide by our friend and colleague, Prof. Alex D. Bain. We dedicate this short review to him.
A magnet moment silenced: A tribute to my friend and mentor Alex D. Bain
Authors: Kay Lewis E. 
Published: April 2018

AbstractAlex D. Bain was an exceptional NMR spectroscopist who played an important role in the development of modern NMR methods and whose keen intellect and wonderful personal qualities endeared him to faculty and students alike who often sought him out for NMR advice. In this brief recollection, I will focus on a number of seminal contributions that Alex made that greatly influenced my research, illustrating how they changed the practice of modern NMR spectroscopy and laid the foundation for new experiments that are currently in widespread use.
Fabrication of an Oil Spill Collector Package by Using Polyurethane Foam Wrapped with Superhydrophobic ZnO Microrods/Carbon Cloth
Authors: Khosravi Maryam , Azizian Saeid 
Published: April 2018

AbstractA new package, including polyurethane foam wrapped with superhydrophobic ZnO microrods/carbon cloth with long‐life elasticity, was fabricated and was utilized for oil spill clean‐up. First, the carbon cloth (CC) was coated with ZnO microrods, which were modified with stearic acid (SA) to obtain superhydrophobic and superoleophilic properties. The coating process was conducted in mild conditions, involving the hydrothermal growth of ZnO microrods on the surface of the carbon cloth. The obtained hydrophobic sample was modified to a superhydrophobic one by adsorption of stearic acid (SA) on its surface. The prepared sample (CC/ZnO/SA) was characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), Fourier transform infrared spectra (FTIR), attenuated total reflectance Fourier‐transform infrared spectroscopy (ATR‐FTIR), and contact angle measurements. The prepared sample shows a water contact angle (WCA) of 160°. A piece of polyurethane foam was wrapped with the prepared superhydrophobic CC/ZnO/SA making an oil collecting package, which can float on the water surface and absorb various oils from the water surface in both static and turbulent conditions very quickly. The prepared package exhibits excellent mechanical robustness and can be used several times for oil/water separation without capacity decrease. The kinetics of oil spill absorption by the prepared package were studied, too.
Assessing the suitable habitat for reintroduction of brown trout (Salmo trutta forma fario) in a lowland river: A modeling approach
Authors: Boets Pieter , Gobeyn Sacha , Dillen Alain , Poelman Eddy , Goethals Peter L. M. 
Published: April 2018

AbstractHuge efforts have been made during the past decades to improve the water quality and to restore the physical habitat of rivers and streams in western Europe. This has led to an improvement in biological water quality and an increase in fish stocks in many countries. However, several rheophilic fish species such as brown trout are still categorized as vulnerable in lowland streams in Flanders (Belgium). In order to support cost‐efficient restoration programs, habitat suitability modeling can be used. In this study, we developed an ensemble of habitat suitability models using metaheuristic algorithms to explore the importance of a large number of environmental variables, including chemical, physical, and hydromorphological characteristics to determine the suitable habitat for reintroduction of brown trout in the Zwalm River basin (Flanders, Belgium), which is included in the Habitats Directive. Mean stream velocity, water temperature, hiding opportunities, and presence of pools or riffles were identified as the most important variables determining the habitat suitability. Brown trout mainly preferred streams with a relatively high mean reach stream velocity (0.2–1 m/s), a low water temperature (7–15°C), and the presence of pools. The ensemble of models indicated that most of the tributaries and headwaters were suitable for the species. Synthesis and applications. Our results indicate that this modeling approach can be used to support river management, not only for brown trout but also for other species in similar geographical regions. Specifically for the Zwalm River basin, future restoration of the physical habitat, removal of the remaining migration barriers and the development of suitable spawning grounds could promote the successful restoration of brown trout.
Parental chronic widespread pain and the association with chronic widespread pain in adult offspring: Family‐linkage data from the Norwegian HUNT Study
Authors: Zadro J.R. , Nilsen T.I.L. , Shirley D. , Amorim A.B. , Ferreira P.H. , Mork P.J. 
Published: April 2018

AbstractBackgroundIndividuals experiencing chronic widespread pain (CWP) have greater disability and poorer quality of life compared to those with other chronic painful conditions; although research identifying risk factors for CWP is lacking. We aimed to investigate whether parental CWP increases the risk of offspring CWP, and if offspring body mass index (BMI) and leisure time physical activity modify this association.MethodsWe included 6589 parent–offspring trios participating in the Norwegian HUNT Study in 1995–1997 and 2006–2008. Logistic regression was used to calculate adjusted odd ratios (ORs) (95% confidence intervals, CIs) as estimates of relative risk for offspring CWP. We analysed the joint effect of parental CWP and offspring BMI or leisure time physical activity on offspring risk of CWP and calculated the relative excess risk due to interaction (RERI).ResultsIn total, 886 (13.5%) offspring developed CWP during follow‐up. Having one (OR = 1.23, 95% CI, 1.05–1.44) or both parents with CWP (OR = 1.89, 95% CI, 1.50–2.38) increased the risk of offspring CWP. In analyses of joint effects, ORs were 1.84 (95% CI, 1.31–2.56) and 3.35 (95% CI, 1.94–5.77) in normal weight and obese offspring, respectively, when both parents had CWP. The estimate of RERI suggested some synergistic effect (RERI = 1.19, 95% CI, −0.68 to 3.05), although precision was low. Risk of CWP was similar in active (OR = 2.05, 95% CI, 1.56–2.70) and inactive (OR = 1.96, 95% CI, 1.31–2.91) offspring when both parents had CWP.ConclusionParental CWP increases the risk of CWP in adult offspring, particularly if both parents have CWP and offspring are obese. This highlights a familial predisposition for CWP and an important target group for preventive measures.SignificanceThe parent–offspring transmission of CWP is stronger in obese offspring (particularly when both parents have CWP). This study is the first to investigate the interaction between modifiable lifestyle factors, familial factors and CWP.
A new sequential injection analysis‐capillary electrophoresis system with amperometric detection
Authors: Fernández Feito Rodrigo , Dinsdale Richard M. , Guwy Alan J. , Premier Giuliano C. 
Published: April 2018

AbstractA novel and fully automated sequential injection analysis manifold coupled to a capillary electrophoresis apparatus with amperometric detection, is described. The sequential injection manifold was isolated from the high voltage by inserting an air plug into the circuit. Small buffer reservoirs were used to avoid the need to pump fresh buffer to the interface during the electrophoretic separation. No decoupling device was used to mitigate the interference from the high voltage electric field, instead the potential shift induced by the separation voltage, was accounted for. The new hydrodynamic injection method presented is based on the overpressure created in the circuit when a pinch valve is closed for a predetermined time. The injection method yields RSD values of peak height and area below 2.55 and 1.82%, respectively, at different durations of valve closure (n = 5). The capillary and working electrode alignment was achieved by adapting a commercial available capillary union. When the electrode was replaced, the alignment method proved to be very reliable, yielding RSD values of peak height and area lower than 2.64 and 2.08%, respectively (n = 8). Using this system with a gold microelectrode, dopamine, and epinephrine could be quantified within the concentration range of 1–500 μM and detected at a concentration of 0.3 μM. The methods here presented could be applied for the development of new capillary electrophoresis systems with amperometric detection and/or to the design of fully automated systems for online process monitoring purposes.
NF‐Y‐dependent regulation of glutamate receptor 4 expression and cell survival in cells of the oligodendrocyte lineage
Authors: Begum Ghazala , Otsu Masahiro , Ahmed Usman , Ahmed Zubair , Stevens Adam , Fulton Daniel 
Published: April 2018

AbstractGlutamate receptor subunit 4 (GluA4) is highly expressed by neural cells sensitive to excitotoxicity, and is the predominant subunit expressed by oligodendrocyte precursor cells (OPC) during a key period of vulnerability to hypoxic‐ischemic injury. Therefore, transcriptional networks downstream of excitotoxic GluA4 activation represent a promising area for therapeutic intervention. In this work, we identify the CCAAT binding transcription factor NF‐Yb as a novel transcriptional regulator of Gria4 (GluA4 gene), and a controller of excitotoxic death in the oligodendroglial lineage. We describe a novel regulatory region within Gria4 containing CCAAT sequences whose binding by NF‐Yb is regulated by excitotoxicity. Excitotoxicity‐induced alterations in NF‐Yb binding are associated with changes in Gria4 transcription, while knockdown of NF‐Yb alters the transcription of reporter constructs containing this regulatory region. Data from immortalized and primary OPC reveal that RNAi and pharmacological disruption of NF‐Yb alter Gria4 transcription, with the latter inducing apoptosis and influencing a set of apoptotic genes similarly regulated during excitotoxicity. These data provide the first definition of a trans‐acting mechanism regulating Gria4, and identify the NF‐Y network as a potential source of pharmacological targets for promoting OPC survival.
Amyloid fibrils induce dysfunction of hippocampal glutamatergic silent synapses
Authors: Bie Bihua , Wu Jiang , Foss Joseph F. , Naguib Mohamed 
Published: April 2018

AbstractSilent glutamatergic synapses lacking functional AMPA (α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazoleproprionate) receptors exist in several brain regions including the hippocampus. Their involvement in the dysfunction of hippocampal glutamatergic transmission in the setting of Alzheimer's disease (AD) is unknown. This study demonstrated a decrease in the percentage of silent synapses in rats microinjected with amyloid fibrils (Aβ1–40) into the hippocampal CA1. Also, pairing low‐frequency electric stimuli failed to induce activation of the hippocampal silent synapses in the modeled rats. Immunoblotting studies revealed a decreased expression of GluR1 subunits in the hippocampal CA1 synaptosomal preparation, indicating a potential reduction in the GluR1 subunits anchoring in postsynaptic density in the modeled rats. We also noted a decreased expression of phosphorylated cofilin, which regulates the function of actin cytoskeleton and receptor trafficking, and reduced expression of the scaffolding protein PSD95 in the hippocampal CA1 synaptosome in rats injected with Aβ1–40. Taken together, this study illustrates dysfunction of hippocampal silent synapse in the rodent model of AD, which might result from the impairments of actin cytoskeleton and postsynaptic scaffolding proteins induced by amyloid fibrils.
Modulation of hippocampal excitability via the hydroxycarboxylic acid receptor 1
Authors: Herrera‐López Gabriel , Galván Emilio J. 
Published: April 2018

AbstractIn addition to its prominent role as an energetic substrate in the brain, lactate is emerging as a signaling molecule capable of controlling neuronal excitability. The finding that the lactate‐activated receptor (hydroxycarboxylic acid receptor 1; HCA1) is widely expressed in the brain opened up the possibility that lactate exerts modulation of neuronal activity via a transmembranal receptor‐linked mechanism. Here, we show that lactate causes biphasic modulation of the intrinsic excitability of CA1 pyramidal cells. In the low millimolar range, lactate or the HCA1 agonist 3,5‐DHBA reduced the input resistance and membrane time constant. In addition, activation of HCA1 significantly blocked the fast inactivating sodium current and increased the delay from inactivation to a conducting state of the sodium channel. As the observed actions occurred in the presence of 4‐CIN, a blocker of the neuronal monocarboxylate transporter, the possibility that lactate acted via neuronal metabolism is unlikely. Consistently, modulation of the intrinsic excitability was abolished when CA1 pyramidal cells were dialyzed with pertussis toxin, indicating the dependency of a Gαi/o‐protein‐coupled receptor. The activation of HCA1 appears to serve as a restraining mechanism during enhanced network activity and may function as a negative feedback for the astrocytic production of lactate.
The 2‐surviving rate of planar graphs with average degree lower than
Authors: Gordinowicz Przemysław 
Published: April 2018

AbstractLet G be any connected graph on n vertices, . Let k be any positive integer. Suppose that a fire breaks out at some vertex of G. Then, in each turn firefighters can protect at most k vertices of G not yet on fire; Next the fire spreads to all unprotected neighbors of burning vertices. The k‐surviving rate of G, denoted by , is the expected fraction of vertices that can be saved from the fire, provided that the starting vertex is chosen uniformly at random. In this note, it is shown that for any planar graph G with average degree , where , there is . In particular, the result implies a significant improvement of the bound for 2‐surviving rate for triangle‐free planar graphs (Esperet et al. ) and for planar graphs without 4‐cycles (Kong et al. ). The proof is done using the separator theorem for planar graphs.
Correlation between herpes zoster and stroke—A case–control study
Authors: Hosamirudsari Hadiseh , Rashed Parisa , Afsari Farhad , Akbarpour Samaneh , Bagherzadeh Aliasghar 
Published: April 2018

Cerebrovascular accident is the second most common cause of death in the world. Herpes zoster (HZ) is reported to be a major trigger of the stroke syndrome. Considering the high prevalence of stroke in Iran, we carried out a study to assess the correlation between stroke and HZ. This is one of the very few studies carried out on this correlation in Asian nations. One hundred and five cases and 105 controls were included in this study. The cases had been diagnosed with stroke by a neurologist and confirmed by brain imaging. The controls had never had any type of stroke. Both groups were between 30 and 90 years of age. We looked for the HZ infection in both groups. Logistic regression analysis was used to evaluate the association between stroke and HZ. The mean age of the cases was 63.95 ± 12.24 years and the man age of the controls was 66.99 ± 14.58 years. There was a significant difference in the HZ infection between the cases and the controls (P < .0001). Head zoster (including ophthalmic zoster) was significantly higher in the case group than the control group (P < .0001). The risk of stroke was the highest 2‐4 weeks after the onset of HZ and the incidences of ischemic stroke were higher than those of hemorrhagic stroke (P < .0001). In an analysis adjusted for the age, sex, and hypertension, HZ was found to be associated with an increased risk of stroke (odds ratio, 5.84; 95% confidence interval, 1.98‐8.23). Close monitoring is suggested for cerebrovascular diseases in patients who have had the head zoster, especially in the first month after the infection.