bluuebunny/crossref_metadata_2025 huggingface dataset:
Variation of energy and carbon fluxes from a restored temperate freshwater wetland and implications for carbon market verification protocols
Authors: Anderson Frank E. , Bergamaschi Brian , Sturtevant Cove , Knox Sara , Hastings Lauren , Windham‐Myers Lisamarie , Detto Matteo , Hestir Erin L. , Drexler Judith , Miller Robin L. , Matthes Jaclyn Hatala , Verfaillie Joseph , Baldocchi Dennis , Snyder Richard L. , Fujii Roger
Published: February 2016

Temperate freshwater wetlands are among the most productive terrestrial ecosystems, stimulating interest in using restored wetlands as biological carbon sequestration projects for greenhouse gas reduction programs. In this study, we used the eddy covariance technique to measure surface energy carbon fluxes from a constructed, impounded freshwater wetland during two annual periods that were 8 years apart: 2002–2003 and 2010–2011. During 2010–2011, we measured methane (CH4) fluxes to quantify the annual atmospheric carbon mass balance and its concomitant influence on global warming potential (GWP). Peak growing season fluxes of latent heat and carbon dioxide (CO2) were greater in 2002–2003 compared to 2010–2011. In 2002, the daily net ecosystem exchange reached as low as −10.6 g C m−2 d−1, which was greater than 3 times the magnitude observed in 2010 (−2.9 g C m−2 d−1). CH4 fluxes during 2010–2011 were positive throughout the year and followed a strong seasonal pattern, ranging from 38.1 mg C m−2 d−1 in the winter to 375.9 mg C m−2 d−1 during the summer. The results of this study suggest that the wetland had reduced gross ecosystem productivity in 2010–2011, likely due to the increase in dead plant biomass (standing litter) that inhibited the generation of new vegetation growth. In 2010–2011, there was a net positive GWP (675.3 g C m−2 yr−1), and when these values are evaluated as a sustained flux, the wetland will not reach radiative balance even after 500 years.
Gluconeogenesis
Authors: Wattanavanitchakorn Siriluck , Jitrapakdee Sarawut
Published: February 2016

Gluconeogenesis is a pivotal biochemical pathway in which glucose is synthesised from non‐carbohydrate precursors, that is, lactate, alanine, glutamine and glycerol, during prolonged starvation. This pathway utilises most glycolytic enzymes in the reverse direction, except the three irreversible steps, which are bypassed by four additional enzymes, pyruvate carboxylase (PC), phosphoeonolpyruvate carboxykinase (PEPCK), fructose‐1,6‐bisphosphatase (FBPase) and glucose‐6‐phosphatase (G6Pase), known as the ‘gluconeogenic enzymes’. Elevated levels of glucagon and glucocorticoids during prolonged fasting stimulate gluconeogenesis in the short and long term. A short‐term response to these hormones involves reversible phosphorylation and allosteric modifications, which can alter the activities of the gluconeogenic enzymes. In contrast, a long‐term response involves the modulation of transcriptional activity of their (nuclear) encoded genes. CREB (cAMP‐responsive element binding protein), FoxO1 (forkhead box O1), PPARα (peroxisome proliferator activated receptor alpha) and PGC1α (peroxisome proliferator activated‐receptor gamma coactivator‐1α) are the key transcription factors that control most gluconeogenic enzymes. Deregulation of glucogeneogic enzymes perturbs systemic glucose homeostasis, causing diabetes.

Key Concepts

Mammals are well adapted to nutrient deprivation in order to survive during food restriction.

Glucose is the sole energy source for brain and red blood cells.

Alteration of glucoregulatory hormones during starvation influences glucose production from liver and kidney by programming relevant biochemical pathways.

Binding of glucoregulatory hormones to their receptors transmits the biochemical signals or molecules that affect the activity of key gluconeogenic enzymes or transcription of gluconeogenic genes.

Loss‐of‐function mutations of gluconeogenic enzyme genes or deregulation of gluconeogenic pathway results in the failure of the body to maintain glucose homeostasis
Eosinophils
Authors: Spencer Lisa A
Published: February 2016

Eosinophils are white blood cells comprising only 1–2% of blood leukocytes, but found in greater concentrations residing within the gastrointestinal tract, thymus, uterus as well as adipose and lymphoid tissues of healthy individuals. The number of eosinophils increases in association with inflammatory diseases including bronchial asthma, helminth infections, hyper‐eosinophilic syndromes and allergic diseases. Eosinophils exhibit cytotoxic effects on microbes and helminths and damage body tissues through secretion of their granule‐derived cationic proteins, and have therefore earned a reputation as end‐stage effector cells. However, the paradigm of eosinophils as strictly end‐stage effectors is evolving. It is now recognised that eosinophils also store a vast array of pre‐formed cytokines within intracellular granules, and undergo distinct modes of degranulation. In large part due to their secretory products, eosinophils participate in health and disease, from metabolic homeostasis to adaptive immunity.

Key Concepts

Eosinophils are present only transiently in the peripheral blood and are primarily tissue‐dwelling cells within the gastrointestinal tract, thymus, uterus as well as lymphoid and adipose tissues.

The number of eosinophils increases during infection with parasitic helminths and allergic inflammatory diseases, such as bronchial asthma.

Eosinophil intracellular granules react avidly with eosin dye because of their storage of strongly cationic proteins, which exert cytotoxic effects on parasites, microbes, tissues and cells.

Because of their secretion of cytotoxic granule‐derived cationic proteins, eosinophils are widely recognised as end‐stage effector cells; however, eosinophils also store and secrete a vast array of cytokines and participate in diverse aspects of health and disease, from metabolic homeostasis to adaptive immunity.

Eosinophils release their granule contents into the extracellular space through three distinct modes of degranulation: classic exocytosis, piecemeal degranulation and cytolysis.

Recent data suggest that cell‐free, extracellularly deposited eosinophil granules expulsed during eosinophil cytolysis remain secretory‐competent organelles within tissues.
Fitness Costs of Plant Disease Resistance
Authors: Bruns Emme
Published: February 2016

Disease is a major agent of evolution by natural selection because infection by a parasite reduces the fitness of its host. Plant populations have evolved many different mechanisms of resistance in response to disease, but, curiously, resistant genotypes rarely supplant susceptible genotypes. Instead, many plant populations are polymorphic at resistance gene loci, meaning that both resistant and susceptible genotypes coexist within a population. The maintenance of polymorphism can be explained if host resistance to disease is most beneficial when most plants are susceptible, and if resistance reduces a plant's fitness in the absence of the parasite. Fitness costs of disease resistance and pathogen virulence are critically important to the maintenance of polymorphism and the direction of host–pathogen coevolution. Costs in conjuncture with host and pathogen life history traits can drive populations towards an ever‐escalating coevolutionary ‘arms‐race’ or can maintain polymorphism through frequency‐dependent selection. Fitness costs of disease resistance may arise in several ways: physiological and metabolic costs of defence against parasites, developmental traits which allow plants to escape disease but are suboptimal for seed production, and trade‐offs between resistance and responses to other microbes. Fitness costs can have important evolutionary consequences in both natural plant populations and in agricultural contexts.

Key Concepts

Fitness costs of resistance are necessary for the long‐term maintenance of polymorphism, but their presence alone does not guarantee stable polymorphism.

Host and pathogen life‐history traits and epidemiology interact with fitness costs of resistance to maintain polymorphism.

When polymorphism is stable, the magnitude of costs determines the frequency of host resistance and pathogen virulence.

Plants defend themselves in multiple ways and these carry different types of costs.

Traits that reduce disease exposure by changing plant growth and phenology tend to be costly.

Fitness costs of resistance can be constitutive or induced.

Resistance to one type of pathogen can come at the cost of increased susceptibility to another type of pathogen.

Costs of resistance and virulence play a role in coevolutionary dynamics in natural populations.

In agricultural populations, costs of resistance and virulence can affect resistance breeding and the durability of resistance.
Molecular Genetics in Acromegaly
Authors: Xekouki Paraskevi , Stratakis Constantine A
Published: February 2016

Pituitary tumours are the most frequent intracranial neoplasms, affecting 1/1000 of the worldwide population. Growth hormone (GH)‐secreting adenomas, also known as somatotropinomas, comprise about 20% of all pituitary tumours. Acromegaly is the clinical syndrome that results from high levels of GH in patients after the end of their growing years, whereas gigantism occurs when high GH acts on a skeleton that is still growing. Most cases of acromegaly/gigantism occur as a result of sporadic GH‐secreting pituitary adenomas. However, in 5% of cases (and significantly more frequently in the young ages), they can occur as a result of a genetic defect, most of the time in association with other endocrine abnormalities or as an isolated disorder. These familial syndromes include multiple endocrine neoplasia (MEN) type 1 (MEN1), Carney complex (CNC), MEN type 4 (MEN4). McCune–Albright syndrome (MAS), familial isolated pituitary adenoma (FIPA), the 3Ps association (pheochromocytoma/paraganglioma and pituitary adenoma syndrome or 3PAs) and X‐linked acrogigantism (X‐LAG).

Key Concepts

About 5% of acromegaly may be caused by a genetic mutation; this may be significantly higher in the young ages.

The frequency of GH‐producing pituitary tumours in MEN1 syndrome is only about 10%, with a mean age at diagnosis comparable to the sporadic GH‐secreting adenomas (40–45 years) but with a more aggressive behaviour.

The incidence of GH‐producing pituitary tumours in Carney complex (CNC) has been estimated to be less than 15%; however, insulin‐like growth factor 1 (IGF‐1) elevation may be present in up to 80% of affected patients who have no detectable tumours due to somatomammotrophic hyperplasia, which may precede clinically evident acromegaly.

GH excess is found in up to 20% of patients with McCune–Albright syndrome mainly due to GH‐producing cell hyperplasia rather than due to pituitary tumours, which are identified in only a few patients.

Somatotropinomas are the most common tumour type in both
AIP
mutation‐positive and ‐negative familial isolated pituitary adenoma (FIPA) families.
AIP
mutation‐positive FIPA patients are more likely to have larger tumours, more likely to invade the extrasellar region and more resistant to medication treatment

GH‐secreting pituitary adenomas in 3PAs due to SDHx mutations display more aggressive phenotype, are more resistant to somatostatin analogues, and most often require surgery

X‐linked acrogigantism (X‐LAG) caused by an Xq26.3 genomic duplication is a paediatric disorder characterised by early onset gigantism resulting from an excess of growth hormone as early as in infancy. The
GPR101
gene duplication most likely causes X‐LAG.
Molecular Genetics of
S
tüve–
W
iedemann Syndrome
Authors: Oxford Julia T
Published: February 2016

Stüve–Wiedemann syndrome (STWS; OMIM #610559) is a rare bent‐bone dysplasia that includes radiologic bone anomalies, respiratory distress, feeding difficulties and hyperthermic episodes. STWS usually results in infant mortality, yet some STWS patients survive at least into early adolescence. STWS is caused by a mutation in the leukaemia inhibitory factor receptor (
LIFR
) gene, which is inherited in an autosomally recessive pattern. Most
LIFR
mutations resulting in STWS are null mutations which cause instability of the mRNA (messenger ribonucleic acid), preventing the formation of LIFR and impairing the signalling pathway. LIFR signalling usually follows the JAK/STAT3 pathway, and is initiated by several interleukin‐6‐type cytokines. STWS is managed on a symptomatic basis, because there is no treatment currently available.

Key Concepts

STWS comprises multiple symptoms affecting multiple physiological systems.

Mutations in LIFR cause mRNA instability, preventing the formation of LIFR protein.

LIFR is important for many IL‐6 cytokine family members; and in the case of LIFR mutations, activities of several cytokines are impaired.

The JAK/STAT3 pathway plays a critical role in STWS.
Effects of the cyberbullying prevention program media heroes (Medienhelden) on traditional bullying
Authors: Chaux Enrique , Velásquez Ana María , Schultze‐Krumbholz Anja , Scheithauer Herbert
Published: February 2016

There is considerable debate over whether cyberbullying is just another form of bullying, or whether it is a problem distinct enough to require specific intervention. One way to explore this issue is to analyze whether programs designed to prevent traditional bullying help prevent cyberbullying, and whether programs designed to prevent cyberbullying prevent traditional bullying. The main goal of the current study was to analyze the spillover effects of the cyberbullying prevention program Media Heroes (Medienhelden) on traditional bullying. Media Heroes promotes empathy, knowledge of risks and consequences, and strategies that allow bystanders to defend victims from cyberbullying. Mixed ANOVAs were conducted comparing pretest and post‐test (6 months after intervention) measures of 722 students (ages 11–17) assigned to a long (15 sessions) intervention, a short (1 day) intervention, and a control group. In addition to confirming the previously reported effects on cyberbullying, Media Heroes was found to reduce traditional bullying. Effects were larger for the long‐version of the program than for the short 1‐day version. No effects were found on victimization by either cyberbullying or traditional bullying. Strategies to complement traditional and cyberbullying prevention efforts are discussed. Aggr. Behav. 42:157–165, 2016. © 2016 Wiley Periodicals, Inc.
Atomically Thin Boron Nitride: Unique Properties and Applications
Authors: Li Lu Hua , Chen Ying
Published: February 2016

Atomically thin boron nitride (BN) is an important 2D nanomaterial, with many properties distinct from graphene. In this feature article, these unique properties and associated applications, often not feasible with graphene, are outlined. The article starts with characterization and identification of atomically thin BN. It is followed by demonstrating their strong oxidation resistance at high temperatures and applications in protecting metals from oxidation and corrosion. As flat insulators, BN nanosheets are ideal dielectric substrates for surface enhanced Raman spectroscopy (SERS) and electronic devices based on 2D heterostructures. The light emission of BN nanosheets in the deep ultraviolet (DUV) and ultraviolet (UV) regions is also included for its scientific and technological importance. The last part is dedicated to synthesis, characterization, and optical properties of BN nanoribbons, a special form of nanosheets.
Emerging and Future Possible Strategies for Enhancing 1D Inorganic Nanomaterials‐Based Electrical Sensors towards Explosives Vapors Detection
Authors: Yang Zheng , Dou Xincun
Published: February 2016

Due to the necessity for maintaining homeland security and antiterrorism, a greatly growing demand exists for sensors that can detect explosives vapors. One‐dimensional inorganic nanomaterials represent one kind of the most promising materials for sensor fabrication due to the large surface‐to‐volume ratios, quantum confinement, high reaction activities, excellent electrical, optical, and chemical properties, unique anisotropic morphologies, and abundant structure tuning capabilities. All of these properties make the 1D inorganic nanomaterials ideal nanoscale building blocks in explosives vapors sensing applications. However, due to the big challenges, such as manufacturing technique with high cost and energy consumption, the difficulty of the assembling and patterning of 1D inorganic nanomaterials into functional devices, the weak repeatability for surface modification which hinder the development of sensors with high sensitivity, selectivity, low power consumption, simple structure, fast response and recovery procedures, high reliability and biocompatibility, more advanced strategies are needed for enhancing 1D‐inorganic‐nanomaterials‐based electrical sensors towards explosives vapors detection. In this article, a comprehensive review of the recent progresses on emerging and future possible strategies for enhancing 1D‐inorganic‐nanomaterials‐based electrical sensors towards explosives vapors detection is provided.
Understanding the Shape Memory Behavior of Self‐Bending Materials and Their Use as Sensors
Authors: Li Xue , Serpe Michael J.
Published: February 2016

By depositing layers composed of poly (N‐isopropylacrylamide)‐based microgels and the polyelectrolyte polydiallyldimethylammonium chloride on a flexible substrate, responsive materials that bend upon drying can be fabricated; the extent of the bending depends on atmospheric humidity. This study shows that the bending conformation/direction can be templated, and exhibits shape memory. Detailed examination of the bilayer system leads to an understanding of the phenomena leading to this behavior. By close examination of microscopy images and diffraction patterns, this study is able to determine that the dried polymer‐based layer is composed of both amorphous and crystalline phases; the amorphous phase can readily absorb water, which results in actuation, while the crystalline phases template the bending characteristics of the device. With an understanding of the bending behavior of the devices, this study is able to generate humidity sensors by interfacing them with stretchable strain sensors, which are also developed specifically for the bendable materials.
Temperature Dependence of Ideality Factors in Organic Solar Cells and the Relation to Radiative Efficiency
Authors: Tvingstedt Kristofer , Deibel Carsten
Published: February 2016

The value and temperature dependence of the ideality factor provides essential information about the dominant recombination route in solar cells. This study presents experimental results of accurate ideality factor determination for representative organic photovoltaic cells (OPV) evaluated at different temperatures over a large current density regime. It is noted that standard dark I–V curves strongly deviate from those obtained by evaluations based on short circuit current density (J
SC)–open circuit voltage (V
OC) pairs. This is attributed to the applied external voltage in a dark I–V measurement not being representative of internal chemical potential, particularly at lower temperatures. Complementary electroluminescence measurements attest that the current density dependence of the ability of the solar cell to emit light is better correlated to the series resistance free ideality factor. For the studied set of OPV devices it is observed that the ideality factors are quite low, and with very weak temperature dependence. The J
SC–V
OC method to determine ideality factors further allows good estimates of activation energies as well as recombination current prefactors J
00. The findings imply that the principal OPV non‐radiative recombination mechanism is not recombination of free carriers with trapped carriers in an exponential density of tail states as previously reported.
Pharmacologic treatment for postviral olfactory dysfunction: a systematic review
Authors: Harless Lucas , Liang Jonathan
Published: February 2016

Background

Postviral olfactory dysfunction (PVOD) is the most common cause of olfactory dysfunction. Several treatments have been presented in the literature. The objective of this study is to systematically review the existing literature on the effectiveness of pharmacologic treatments for PVOD.

Methods

We performed a literature search of PubMed, Ovid, and ScienceDirect from 1966 to 2014. Inclusion criteria included English‐language articles containing original data on pharmacologic treatment of PVOD with ≥5 subjects, measurable outcomes, and readily available treatments. Data was collected regarding study design, subject demographic information, clinical outcomes, and level of evidence. Two investigators reviewed all articles independently.

Results

Of 445 abstracts identified, 8 articles were included, yielding 563 patients. Treatments investigated included oral corticosteroids, local injections of corticosteroids, zinc sulfate, alpha lipoic acid, caroverine, vitamin A, Ginkgo biloba, and minocycline. Outcome measures were determined by symptom scores and objective olfactory test methods—the most common being Sniffin’ Sticks. Improvement was noted in subjects receiving oral corticosteroid therapy, local injections of corticosteroid, alpha lipoic acid, and caroverine, whereas vitamin A, zinc sulfate, Ginkgo biloba, and minocycline groups did not show significant improvement.

Conclusion

The majority of therapies investigated that show benefit in treating PVOD are of poor quality. Although caroverine therapy showed benefit and is a level 1b study, etiologies of olfactory dysfunction other than PVOD were included as well, which clouds the results. Overall, there is no strong evidence for any pharmacologic treatment of PVOD in the literature.
The effect of blood pressure and cardiac output on the quality of the surgical field and middle cerebral artery blood flow during endoscopic sinus surgery
Authors: Ha Thanh Ngoc , van Renen Robert Graham , Ludbrook Guy L. , Wormald Peter‐John
Published: February 2016

Background

A clear surgical field is critical during endoscopic sinus surgery (ESS). Hypotensive anesthesia and cardiac output (CO) may optimize the surgical field; however, evidence of their effect on bleeding and cerebral blood flow is conflicting. The aim of this study was to evaluate the effect of blood pressure (BP) and CO on intraoperative bleeding and middle cerebral artery blood flow velocity (Vmca) during ESS.

Methods

This was a prospective randomized controlled trial. Patients undergoing ESS for chronic rhinosinusitis at a tertiary institution in 2013 were randomized to receive BP manipulation using target‐controlled noradrenaline infusion during surgery to either their left or right sinuses. The contralateral side in each patient served as control. Bleeding was scored using a 0 to 10 point bleeding assessment scale (BAS, 0–10) and Vmca was measured using transcranial Doppler ultrasonography every 10 minutes or when surgically opportune, and time‐matched with BP and CO. Data was analyzed using Bland–Altman methods.

Results

A total of 105 time points were collected across a mean arterial pressure (MAP) range of 32 to 118 mmHg. Significant correlations were demonstrated between MAP and Vmca (r = 0.7, p < 0.0001), MAP and BAS (r = 0.50, p < 0.0001), CO and Vmca (r = 0.57, p < 0.0001), and CO and BAS (r = 0.42, p < 0.0001). The best surgical fields were seen at 40 to 59 mmHg MAP. However, MAP below 60 mmHg produced >50% reduction in Vmca in more than 10% of time points.

Conclusion

Balancing surgical visibility with organ perfusion remains a challenge. The results of this study show that moderate hypotension significantly improves the surgical field; however reducing BP below 60 mmHg may risk cerebral hypoperfusion.
Palladium‐Catalyzed, tert‐Butyllithium‐Mediated Dimerization of Aryl Halides and Its Application in the Atropselective Total Synthesis of Mastigophorene A
Authors: Buter Jeffrey , Heijnen Dorus , Vila Carlos , Hornillos Valentín , Otten Edwin , Giannerini Massimo , Minnaard Adriaan J. , Feringa Ben L.
Published: February 2016

A palladium‐catalyzed direct synthesis of symmetric biaryl compounds from aryl halides in the presence of tBuLi is described. In situ lithium–halogen exchange generates the corresponding aryl lithium reagent, which undergoes a homocoupling reaction with a second molecule of the aryl halide in the presence of the palladium catalyst (1 mol %). The reaction takes place at room temperature, is fast (1 h), and affords the corresponding biaryl compounds in good to excellent yields. The application of the method is demonstrated in an efficient asymmetric total synthesis of mastigophorene A. The chiral biaryl axis is constructed with an atropselectivity of 9:1 owing to catalyst‐induced remote point‐to‐axial chirality transfer.
Metastable Nitric Acid Trihydrate in Ice Clouds
Authors: Weiss Fabian , Kubel Frank , Gálvez Óscar , Hoelzel Markus , Parker Stewart F. , Baloh Philipp , Iannarelli Riccardo , Rossi Michel J. , Grothe Hinrich
Published: February 2016

The composition of high‐altitude ice clouds is still a matter of intense discussion. The constituents in question are ice and nitric acid hydrates, but the exact phase composition of clouds and its formation mechanisms are still unknown. In this work, conclusive evidence for a long‐predicted phase, alpha‐nitric acid trihydrate (alpha‐NAT), is presented. This phase was characterized by a combination of X‐ray and neutron diffraction experiments, allowing a convincing structure solution. Furthermore, vibrational spectra (infrared and inelastic neutron scattering) were recorded and compared with theoretical calculations. A strong interaction between water ice and alpha‐NAT was found, which explains the experimental spectra and the phase‐transition kinetics. On the basis of these results, we propose a new three‐step mechanism for NAT formation in high‐altitude ice clouds.
Biodegradable Inorganic Nanovector: Passive versus Active Tumor Targeting in siRNA Transportation
Authors: Park Dae‐Hwan , Cho Jaeyong , Kwon Oh‐Joon , Yun Chae‐Ok , Choy Jin‐Ho
Published: February 2016

The biodegradable inorganic nanovector based on a layered double hydroxide (LDH) holds great promise for gene and drug delivery systems. However, in vivo targeted delivery of genes through LDH still remains a key challenge in the development of RNA interference therapeutics. Here, we describe in vivo and in vitro delivery system for Survivin siRNA (siSurvivin) assembled with passive LDH with a particle size of 100 nm or active LDH conjugated with a cancer overexpressing receptor targeting ligand, folic acid (LDHFA), conferring them an ability to target the tumor by either EPR‐based clathrin‐mediated or folate receptor‐mediated endocytosis. When not only transfected into KB cells but also injected into xenograft mice, LDHFA/siSurvivin induced potent gene silencing at mRNA and protein levels in vitro, and consequently achieved a 3.0‐fold higher suppression of tumor volume than LDH/siSurvivin in vivo. This anti‐tumor effect was attributed to a selectively 1.2‐fold higher accumulation of siSurvivin in tumor tissue compared with other organs. Targeting to the tumor with inorganic nanovector can guide and accelerate an evolution of next‐generation theranosis system.
Phenyl‐Modified Carbon Nitride Quantum Dots with Distinct Photoluminescence Behavior
Authors: Cui Qianling , Xu Jingsan , Wang Xiaoyu , Li Lidong , Antonietti Markus , Shalom Menny
Published: February 2016

A novel type of quantum dot (Ph‐CN) is manufactured from graphitic carbon nitride by “lining” the carbon nitride structure with phenyl groups through supramolecular preorganization. This approach requires no chemical etching or hydrothermal treatments like other competing nanoparticle syntheses and is easy and safe to use. The Ph‐CN nanoparticles exhibit bright, tunable fluorescence, with a high quantum yield of 48.4 % in aqueous colloidal suspensions. Interestingly, the observed Stokes shift of approximately 200 nm is higher than the maximum values reported for carbon nitride based fluorophores. The high quantum yield and the large Stokes shift are related to the structural surface organization of the phenyl groups, which affects the π‐electron delocalization in the conjugated carbon nitride networks and induces colloidal stability. The remarkable performance of the Ph‐CN nanoparticles in imaging is demonstrated by a simple incubation study with HeLa cells.
A Rhodium–Pentane Sigma‐Alkane Complex: Characterization in the Solid State by Experimental and Computational Techniques
Authors: Chadwick F. Mark , Rees Nicholas H. , Weller Andrew S. , Krämer Tobias , Iannuzzi Marcella , Macgregor Stuart A.
Published: February 2016

The pentane σ‐complex [Rh{Cy2P(CH2CH2)PCy2}(η2:η2‐C5H12)][BArF4] is synthesized by a solid/gas single‐crystal to single‐crystal transformation by addition of H2 to a precursor 1,3‐pentadiene complex. Characterization by low temperature single‐crystal X‐ray diffraction (150 K) and SSNMR spectroscopy (158 K) reveals coordination through two Rh⋅⋅⋅H−C interactions in the 2,4‐positions of the linear alkane. Periodic DFT calculations and molecular dynamics on the structure in the solid state provide insight into the experimentally observed Rh⋅⋅⋅H−C interaction, the extended environment in the crystal lattice and a temperature‐dependent pentane rearrangement implicated by the SSNMR data.
Synthesis of Highly Functionalized 4‐Aminoquinolines
Authors: Wezeman Tim , Zhong Sabilla , Nieger Martin , Bräse Stefan
Published: February 2016

A diverse set of highly substituted 4‐aminoquinolines was synthesized from ynamides, triflic anhydride, 2‐chloropyridine, and readily accessible amides in a mild one‐step procedure.
Highly Unsaturated Platinum and Palladium Carbenes PtC3 and PdC3 Isolated and Characterized in the Gas Phase
Authors: Bittner Dror M. , Zaleski Daniel P. , Tew David P. , Walker Nicholas R. , Legon Anthony C.
Published: February 2016

Carbenes of platinum and palladium, PtC3 and PdC3, were generated in the gas phase through laser vaporization of a metal target in the presence of a low concentration of a hydrocarbon precursor undergoing supersonic expansion. Rotational spectroscopy and ab initio calculations confirm that both molecules are linear. The geometry of PtC3 was accurately determined by fitting to the experimental moments of inertia of twenty‐six isotopologues. The results are consistent with the proposal of an autogenic isolobal relationship between O, Au+, and Pt atoms.
Mechanochemical Iridium(III)‐Catalyzed C−H Bond Amidation of Benzamides with Sulfonyl Azides under Solvent‐Free Conditions in a Ball Mill
Authors: Hermann Gary N. , Becker Peter , Bolm Carsten
Published: February 2016

Mechanochemical conditions have been applied to an iridium(III)‐catalyzed C−H bond amidation process for the first time. In the absence of solvent, the mechanochemical activation enables the formation of an iridium species that catalyzes the ortho‐selective amidation of benzamides with sulfonyl azides as the nitrogen source. As the reaction proceeds in the absence of organic solvents without external heating and yields the desired products in excellent yields within short reaction times, this method constitutes a powerful, fast, and environmentally benign alternative to the common solvent‐based standard approaches.
Direct Spectroscopic Evidence for an n→π* Interaction
Authors: Singh Santosh K. , Mishra Kamal K. , Sharma Neha , Das Aloke
Published: February 2016

The n→π* interaction is an extremely weak but very important noncovalent interaction. Although this interaction is widely present in biomolecules and materials, its existence is counterintuitive and so has been debated extensively. Herein, we have reported direct spectroscopic evidence for an n→π* interaction for the first time by probing the carbonyl stretching frequency in phenyl formate using isolated gas‐phase IR spectroscopy. This result also demonstrates that the conformational preference for the cis conformer of phenyl formate compared to the trans conformer arises due to the presence of the n→π* interaction in the former. The direct proof reported herein for this controversial but important noncovalent interaction should stimulate further experimental and theoretical investigation on this intriguing research topic.
Effect of Electrolyte Concentration on the Stern Layer Thickness at a Charged Interface
Authors: Brown Matthew A. , Goel Alok , Abbas Zareen
Published: February 2016

The chemistry and physics of charged interfaces is regulated by the structure of the electrical double layer (EDL). Herein we quantify the average thickness of the Stern layer at the silica (SiO2) nanoparticle/aqueous electrolyte interface as a function of NaCl concentration following direct measurement of the nanoparticles’ surface potential by X‐ray photoelectron spectroscopy (XPS). We find the Stern layer compresses (becomes thinner) as the electrolyte concentration is increased. This finding provides a simple and intuitive picture of the EDL that explains the concurrent increase in surface charge density, but decrease in surface and zeta potentials, as the electrolyte concentration is increased.
Catalytic Asymmetric Tandem Reaction of Tertiary Enamides: Expeditious Synthesis of Pyrrolo[2,1‐a]isoquinoline Alkaloid Derivatives
Authors: Xu Xin‐Ming , Zhao Liang , Zhu Jieping , Wang Mei‐Xiang
Published: February 2016

Reported is a new and efficient strategy for rapid construction of the chiral tetrahydropyrrolo[2,1‐a]isoquinolin‐3(2H)‐one structure from unique tertiary enamide synthons. A Cu(OTf)2/chiral Pybox complex catalyzes the intramolecular enantioselective addition of tertiary enamides to ketonic carbonyls with subsequent diastereoselective interception of the resulting acyliminium by tethered electron‐rich aryl moiety. The tandem reaction produces diverse tetrahydropyrrolo[2,1‐a]isoquinolin‐3(2H)‐one derivatives as the sole diastereoisomers in good to excellent yields with up to 98.5 % ee. The transformations of the resulting heterocycles into various hexahydropyrrolo[2,1‐a]isoquinoline derivatives were also demonstrated. The cyclization products, which are difficult to obtain by other synthetic means, are structural motifs found in many bioactive alkaloids.
Development of lightweight high‐performance polymeric composites with functionalized nanotubes
Authors: Vijayan Vigil Jasmin , Arun A. , Bhowmik Shantanu , Abraham Mathew , Ajeesh G. , Pitchan Mohan Kumar
Published: February 2016

In this article, we highlight the various properties of an ultralightweight poly(ether ketone) (PEK) composite. In this study, special emphases were laid on the preparation of low‐density, high‐performance polymeric foams with foaming agents and activators. PEK, foamed PEK, and carbon nanotube (CNT)–reinforced foamed PEK composites were considered for this study. The density of the polymer decreased with the reinforcement of the foaming agent. We also noted that with the reinforcement of the modified CNT in the foamed PEK, there were marginal increases in the density and hardness of the composites. We also noted that the mechanical properties of the CNT‐reinforced foamed PEK was on par with those of basic PEK. Thermogravimetric analysis gave us a clear indication that the thermal stability of the composites was not affected by the reinforcing foaming agent and nanoparticles. Scanning electron microscopy and transmission electron microscopy clearly indicated the formation of foams and also the dispersion of nanoparticles in the composite structure. We also observed that because of the reinforcement of multiwalled CNTs in the composite, there was an improvement in the hardness of the composite. An increase in the specific strength was observed in the foamed PEK composites. The CNT‐reinforced foamed PEK showed a marginal decrease in the specific strength without a compromise in the impact strength. The impact strength of the CNT‐reinforced foamed PEK composite was found to be similar to that of the basic PEK. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43471.
Changes in Body Mass Related to the Initiation of Disease‐Modifying Therapies in Rheumatoid Arthritis
Authors: Baker Joshua F. , Sauer Brian C. , Cannon Grant W. , Teng Chia‐Chen , Michaud Kaleb , Ibrahim Said , Jorgenson Erik , Davis Lisa , Caplan Liron , Cannella Amy , Mikuls Ted R.
Published: February 2016

Objective

Unintentional weight loss is important and can be predictive of long‐term outcomes in patients with rheumatoid arthritis (RA). This study was undertaken to assess how primary therapies for RA may influence changes in body mass index (BMI) in RA patients from a large administrative database.

Methods

Unique dispensing episodes of methotrexate, prednisone, leflunomide, and tumor necrosis factor inhibitors (TNFi) administered to RA patients were identified from the US Department of Veterans Affairs pharmacy databases. Values for C‐reactive protein (CRP) level and BMI closest to the time point within 30 days of the treatment course start date and at follow‐up time points were linked. Missing laboratory values were imputed. Weight loss was defined as a decrease in BMI of >1 kg/m2. Regression models were used to evaluate changes in BMI during each drug treatment as compared to treatment with methotrexate. To assess the impact of confounding by indication, propensity scores for use of each drug were incorporated in analyses using matched‐weighting techniques.

Results

In total, 52,662 treatment courses in 32,859 RA patients were identified. At 6 months from the date of prescription fill, weight gain was seen among patients taking methotrexate, those taking prednisone, and those taking TNFi. On average, compared to methotrexate‐treated patients, prednisone‐treated patients had significantly more weight gain, while leflunomide‐treated patients demonstrated weight loss. In multivariable models, more weight loss (β = −0.41 kg/m2, 95% confidence interval [95% CI] −0.46, −0.36; P < 0.001) and a greater risk of weight loss (odds ratio 1.73, 95% CI 1.55, 1.79; P < 0.001) were evident among those receiving leflunomide compared to those receiving methotrexate. Treatment with prednisone was associated with greater weight gain (β = 0.072 kg/m2, 95% CI 0.042, 0.10; P < 0.001). These associations persisted in analyses adjusted for propensity scores and in sensitivity analyses.

Conclusion

Leflunomide is associated with significantly more, but modest, weight loss, while prednisone is associated with greater weight gain compared to other therapies for RA.
Synthesis and Applications of (ONO Pincer)Ruthenium‐Complex‐Bound Norvalines
Authors: Isozaki Katsuhiro , Yokoi Tomoya , Yoshida Ryota , Ogata Kazuki , Hashizume Daisuke , Yasuda Nobuhiro , Sadakane Koichiro , Takaya Hikaru , Nakamura Masaharu
Published: February 2016

Two (ONO pincer)ruthenium‐complex‐bound norvalines, Boc−[Ru(pydc)(terpy)]Nva−OMe (1; Boc=tert‐butyloxycarbonyl, terpy=terpyridyl, Nva=norvaline) and Boc−[Ru(pydc)(tBu‐terpy)]Nva−OMe (5), were successfully synthesized and their molecular structures and absolute configurations were unequivocally determined by single‐crystal X‐ray diffraction. The robustness of the pincer Ru complexes and norvaline scaffolds against acidic/basic, oxidizing, and high‐temperature conditions enabled us to perform selective transformations of the N‐Boc and C−OMe termini into various functional groups, such as alkyl amide, alkyl urea, and polyether groups, without the loss of the Ru center or enantiomeric purity. The resulting dialkylated Ru‐bound norvaline, n‐C11H23CO−l‐[Ru(pydc)(terpy)]Nva−NH‐n‐C11H23 (l‐4) was found to have excellent self‐assembly properties in organic solvents, thereby affording the corresponding supramolecular gels. Ru‐bound norvaline l‐1 exhibited a higher catalytic activity for the oxidation of alcohols by H2O2 than parent complex [Ru(pydc)(terpy)] (11 a).
Normalization of doxorubicin release from graphene oxide: New approach for optimization of effective parameters on drug loading
Authors: Hashemi Mohadeseh , Yadegari Amir , Yazdanpanah Ghasem , Omidi Meisam , Jabbehdari Sayena , Haghiralsadat Fatemeh , Yazdian Fatemeh , Tayebi Lobat
Published: February 2016

Graphene oxide (GO) has been recently introduced as a suitable anticancer drug carrier, which could be loaded with doxorubicin (DOX) as a general chemotherapy agent. Herein, the attempts were made to optimize the effective parameters on both loading and release of DOX on GO. GO and GO–DOX were characterized using transition electron microscopy , zeta potential, Raman spectroscopy, UV–visible spectroscopy, and Fourier transform infrared spectroscopy. In addition, loading and releasing behaviors of DOX on GO were studied in terms of different temperature and pH values. The primary optimized values of pH and temperature for best‐loaded amount of DOX were 8.9 and 309 K, respectively. Moreover, we found that the smallest amount of released DOX, in pH of cancer microenvironment (5.4), occurs when DOX had been previously loaded in pH 7.8 and 310 K. Although the highest amount of loaded DOX was in basic pH, the results of efficient release of DOX from the GO–DOX complex and also cellular toxicity assay revealed that the best pH for loading of DOX on GO was 7.8. Therefore, in addition to optimization of parameters for efficient loading of DOX on GO, this study suggested that normalization of a released drug compared with the amount of a loaded drug could be a new approach for optimization of drug loading on nanocarriers.
Insights into the binding of ferulic acid to the thermally treated xanthine oxidase
Authors: Dumitrascu Loredana , Stănciuc Nicoleta , Bahrim Gabriela Elena , Aprodu Iuliana
Published: February 2016

Ferulic acid (FA) is a biologically active compound used as an additive in the food industry, and possesses a wide range of therapeutic effects for treating different health problems. The interaction between FA and bovine xanthine oxidase (XOD) has been investigated by means of fluorescence spectroscopy methods. The numbers of binding sites and the binding constants were estimated at various temperatures and the results indicated the existence of one specific FA binding site of XOD. Detailed information on the interaction between molecules gathered after performing in silico molecular docking indicated the accommodation of the FA molecule in a XOD binding pocket, in close vicinity to the active site residues. The formation of the XOD–FA complex causes the quenching of protein fluorescence. The process followed a static mechanism at lower temperatures, and a dynamic mechanism at higher temperatures. The thermodynamic parameters calculated on the basis of different temperatures revealed that the association between FA and XOD is a spontaneous process driven by enthalpy and dominated by hydrogen bonding and van der Waals interaction. The results of synchronous fluorescence and 3D fluorescence spectra showed that the conformation of protein was altered in the presence of FA. Copyright © 2016 John Wiley & Sons, Ltd.
Peripheral (deep) but not periventricular MRI white matter hyperintensities are increased in clinical vascular dementia compared to Alzheimer's disease
Authors: Smith Charles D. , Johnson Eleanor S. , Van Eldik Linda J. , Jicha Gregory A. , Schmitt Frederick A. , Nelson Peter T. , Kryscio Richard J. , Murphy Ronan R. , Wellnitz Clinton V.
Published: February 2016

Background and purpose

Vascular dementia (VAD) is a complex diagnosis at times difficult to distinguish from Alzheimer's disease (AD). MRI scans often show white matter hyperintensities (WMH) in both conditions. WMH increase with age, and both VAD and AD are associated with aging, thus presenting an attribution conundrum. In this study, we sought to show whether the amount of WMH in deep white matter (dWMH), versus periventricular white matter (PVH), would aid in the distinction between VAD and AD, independent of age.

Methods

Blinded semiquantitative ratings of WMH validated by objective quantitation of WMH volume from standardized MRI image acquisitions. PVH and dWMH were rated separately and independently by two different examiners using the Scheltens scale. Receiver operator characteristic (ROC) curves were generated using logistic regression to assess classification of VAD (13 patients) versus AD (129 patients). Clinical diagnoses were made in a specialty memory disorders clinic.

Results

Using PVH rating alone, overall classification (area under the ROC curve, AUC) was 75%, due only to the difference in age between VAD and AD patients in our study and not PVH. In contrast, dWMH rating produced 86% classification accuracy with no independent contribution from age. A global Longstreth rating that combines dWMH and PVH gave an 88% AUC.

Conclusions

Increased dWMH indicate a higher likelihood of VAD versus AD. Assessment of dWMH on MRI scans using Scheltens and Longstreth scales may aid the clinician in distinguishing the two conditions.
Brain and behavior changes associated with an abbreviated 4‐week mindfulness‐based stress reduction course in back pain patients
Authors: Braden B. Blair , Pipe Teri B. , Smith Ryan , Glaspy Tyler K. , Deatherage Brandon R. , Baxter Leslie C.
Published: February 2016

Introduction

Mindfulness‐based stress reduction (MBSR) reduces depression, anxiety, and pain for people suffering from a variety of illnesses, and there is a growing need to understand the neurobiological networks implicated in self‐reported psychological change as a result of training. Combining complementary and alternative treatments such as MBSR with other therapies is helpful; however, the time commitment of the traditional 8‐week course may impede accessibility. This pilot study aimed to (1) determine if an abbreviated MBSR course improves symptoms in chronic back pain patients and (2) examine the neural and behavioral correlates of MBSR treatment.

Methods

Participants were assigned to 4 weeks of weekly MBSR training (n = 12) or a control group (stress reduction reading; n = 11). Self‐report ratings and task‐based functional MRI were obtained prior to, and after, MBSR training, or at a yoked time point in the control group.

Results

While both groups showed significant improvement in total depression symptoms, only the MBSR group significantly improved in back pain and somatic‐affective depression symptoms. The MBSR group also uniquely showed significant increases in regional frontal lobe hemodynamic activity associated with gaining awareness to changes in one's emotional state.

Conclusions

An abbreviated MBSR course may be an effective complementary intervention that specifically improves back pain symptoms and frontal lobe regulation of emotional awareness, while the traditional 8‐week course may be necessary to detect unique improvements in total anxiety and cognitive aspects of depression.