bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wernicke–Korsakoff Syndrome
Authors: Sechi Gian Pietro , Fancellu Laura , Doneddu Pietro , Sechi Elia 
Published: November 2014

Abstract

Wernicke–Korsakoff syndrome refers to a life‐threatening encephalopathy due to inadequate supply of thiamine (vitamin B1) to the brain. It is a combination of Wernicke encephalopathy (WE), an acute neuropsychiatric disorder fully responsive to prompt and adequate thiamine replacement, and Korsakoff syndrome (KS), the chronic, irreversible form of WE that does not remit with thiamine treatment. Thiamine deficiency can occur in any condition of unbalanced nutrition that lasts for 2–3 weeks. These include poor nutrition, chronic alcohol misuse, loss of thiamine owing to recurrent vomiting or malabsorption, increased thiamine requirements owing to chronic diseases, prolonged and excessive carbohydrate intake and gastrointestinal surgical procedures, in particular, patients after bariatric surgery. The diagnosis is clinical and is mainly supported by the dramatic improvement of neurological signs to parenteral thiamine. Neuroimaging studies are useful to confirm the diagnosis of both WE and KS. Patients with suspected thiamine deficiency should be treated immediately with parenteral thiamine at the doses deemed to be effective in the treatment of WE and prevention of KS.

Key Concepts:

Thiamine deficiency can occur in a myriad of clinical settings that include malnutrition, malabsorption and increased metabolism and in patients following bariatric surgery.

A thiamine deficiency that lasts for 2 to 3 weeks leads to Wernicke encephalopathy, an acute, life‐threatening disorder that is a medical emergency.

Wernicke encephalopathy is fully responsive to prompt and adequate thiamine replacement.

Untreated or inadequately treated Wernicke encephalopathy may lead to Korsakoff syndrome, a chronic amnesic encephalopathy that does not remit with thiamine treatment.

The goal of treatment of Wernicke encephalopathy is the immediate administration of high doses of parenteral thiamine deemed sufficient to prevent Korsakoff syndrome.
Air pollutants cause release of hydrogen peroxide and interleukin‐8 in a human primary nasal tissue culture model
Authors: Cho Do‐Yeon , Le Wei , Bravo Dawn T. , Hwang Peter H. , Illek Beate , Fischer Horst , Nayak Jayakar V. 
Published: November 2014

BackgroundA component of primary innate defense of the nasal mucosa against inhaled pathogens includes continuous, low‐level release of hydrogen peroxide (H2O2) into luminal secretions. Epidemiologically, an association exists between poor air quality and increased prevalence of sinonasal disease. To understand the effects of particulate matter (PM) in nasal mucosa, we studied the release of H2O2 and interleukin 8 (IL‐8) after PM exposure.MethodsHuman nasal specimens were collected from surgery and cultured in serum‐free growth medium. Cell integrity and recovery during culture was monitored by lactate dehydrogenase (LDH) release into the medium. Cultures were exposed to PM for 24 hours in the presence/absence of diphenyleneiodonium sulfate (DPI; a nicotinamide adenine dinucleotide phosphate [NADPH] oxidase inhibitor). Luminex cytokine and Amplex‐Red H2O2 assays were performed.ResultsLDH levels dropped rapidly within 2 days, indicative of stabilization and cell recovery after harvest. All cultures released H2O2 into the medium. Exposure to PM (20 μg/cm2) increased H2O2 levels significantly (94.6 ± 7.7 nM) compared to untreated controls (55.8 ± 4.0 nM; p = 0.001). PM‐induced H2O2 production was partially inhibited by DPI (80.1 ± 3.8nM), indicating that cellular NADPH oxidase may be a primary source of H2O2 production. Exposure to PM increased IL‐8 levels in a dose‐dependent fashion (control = 2301 ± 412 MFI; 20 μg/cm2 = 5002 ± 1327 MFI; 40 μg/cm2 = 8219 ± 1090 MFI; p = 0.022).ConclusionPM increases the quantity of H2O2 released by nasal epithelial cells, indicating that PM can contribute to oxidative stress in part by activating a normal cellular defense mechanism. Exposure to PM resulted in elevated IL‐8 levels and mucin production in explants. Efforts to reduce airborne PM may lead to reduced H2O2 and mucin production in sinonasal epithelium.
Integration of signal timing estimation model and dynamic traffic assignment in feedback loops: system design and case study
Authors: Zlatkovic Milan , Zhou Xuesong 
Published: November 2014

SummaryThis paper presents an integrated framework for effective coupling of a signal timing estimation model and dynamic traffic assignment (DTA) in feedback loops. There are many challenges in effectively integrating signal timing tools with DTA software systems, such as data availability, exchange format, and system coupling. In this research, a tight coupling between a DTA model with various queue‐based simulation models and a quick estimation method Excel‐based signal control tool is achieved and tested. The presented framework design offers an automated solution for providing realistic signal timing parameters and intersection movement capacity allocation, especially for future year scenarios. The framework was used to design an open‐source data hub for multi‐resolution modeling in analysis, modeling and simulation applications, in which a typical regional planning model can be quickly converted to microscopic traffic simulation and signal optimization models. The coupling design and feedback loops are first demonstrated on a simple network, and we examine the theoretically important questions on the number of iterations required for reaching stable solutions in feedback loops. As shown in our experiment, the current coupled application becomes stable after about 30 iterations, when the capacity and signal timing parameters can quickly converge, while DTA's route switching model predominately determines and typically requires more iterations to reach a stable condition. A real‐world work zone case study illustrates how this application can be used to assess impacts of road construction or traffic incident events that disrupt normal traffic operations and cause route switching on multiple analysis levels. Copyright © 2014 John Wiley & Sons, Ltd.
Fluorescence quantum yield measurements of fluorescent proteins: A laboratory experiment for a biochemistry or molecular biophysics laboratory course
Authors: Wall Kathryn P. , Dillon Rebecca , Knowles Michelle K. 
Published: November 2014

AbstractFluorescent proteins are commonly used in cell biology to assess where proteins are within a cell as a function of time and provide insight into intracellular protein function. However, the usefulness of a fluorescent protein depends directly on the quantum yield. The quantum yield relates the efficiency at which a fluorescent molecule converts absorbed photons into emitted photons and it is necessary to know for assessing what fluorescent protein is the most appropriate for a particular application. In this work, we have designed an upper‐level, biochemistry laboratory experiment where students measure the fluorescence quantum yields of fluorescent proteins relative to a standard organic dye. Four fluorescent protein variants, enhanced cyan fluorescent protein (ECFP), enhanced green fluorescent protein (EGFP), mCitrine, and mCherry, were used, however the methods described are useful for the characterization of any fluorescent protein or could be expanded to fluorescent quantum yield measurements of organic dye molecules. The laboratory is designed as a guided inquiry project and takes two, 4 hr laboratory periods. During the first day students design the experiment by selecting the excitation wavelength, choosing the standard, and determining the concentration needed for the quantum yield experiment that takes place in the second laboratory period. Overall, this laboratory provides students with a guided inquiry learning experience and introduces concepts of fluorescence biophysics into a biochemistry laboratory curriculum. © 2014 by The International Union of Biochemistry and Molecular Biology, 43(1):52–59, 2015.
Learning about solubility
Authors: Salinas Dino G. , Reyes Juan G. 
Published: November 2014

AbstractQualitative questions are proposed to assess the understanding of solubility and some of its applications. To improve those results, a simple quantitative problem on the precipitation of proteins is proposed. © 2014 by The International Union of Biochemistry and Molecular Biology, 43(1):3–5, 2015.
A Comprehensive Kinetic Study of the Reaction of SO2 with CaO by the Random Pore Model
Authors: Moshiri Hadi , Nasernejad Bahram , Ebrahim Habib Ale , Taheri Mahboobeh 
Published: November 2014

AbstractThe kinetics of the reaction between CaO and SO2 was studied by the random pore model, to accurately consider the porous structure of the solid reactant. The inherent reaction rate constants and rate dependency with respect to the SO2 concentration were determined from the initial slopes of the conversion‐time profiles obtained by thermogravimetry. A power law concentration dependency was applied and then the first‐order kinetics was verified. The product layer diffusivity was evaluated from the comparison of whole experimental conversion‐time profiles with the model predictions.
Nanopatterned Superlattices in Self‐Assembled C2‐Symmetric Oligodimethylsiloxane‐Based Benzene‐1,3,5‐Tricarboxamides
Authors: García‐Iglesias Miguel , de Waal Bas F. M. , de Feijter Isja , Palmans Anja R. A. , Meijer E. W. 
Published: November 2014

AbstractThe synthesis of C3‐ and C2‐symmetric benzene‐1,3,5‐tricarboxamides (BTAs) containing well‐defined oligodimethylsiloxane (oDMS) and/or alkyl side chains has been carried out. The influence of the bulkiness of the oDMS chains in the aggregation behavior of dilute solutions of the oDMS‐BTAs in methylcyclohexane was studied by temperature‐dependent UV spectroscopy. The formation of hierarchically self‐assembled aggregates was observed at different BTA concentrations, the tendency of aggregation increases by shortening or removing oDMS chains. Chiral BTAs were investigated with circular dichroism (CD) spectroscopy, showing a stronger tendency to aggregate than the achiral ones. Majority rules experiments show a linear behavior consistent with the existence of a high mismatch penalty energy. The most efficient oDMS‐BTAs organogelators have the ability to form stable organogels at 5 mg mL−1 (0.75 wt %) in hexane. Solid‐state characterization techniques indicate the formation of an intermolecular threefold hydrogen bonding between adjacent molecules forming thermotropic liquid crystals, exhibiting a hexagonal columnar organization from room temperature to above 150 °C. A decrease of the clearing temperatures was observed when increasing the number and length of the oligodimethylsiloxane chains. In addition to the three‐fold hydrogen bonding that leads to columnar liquid crystalline phase, segregation between the oDMS and aliphatic chains takes place in the BTA functionalized with two alkyl and one oDMS chain leading to a superlattice within the hexagonal structure with potential applications in lithography.
A Facile Top‐Down Protocol for Postsynthesis Modification of Hierarchical Aluminum‐Rich MFI Zeolites
Authors: Yu Lili , Huang Shengjun , Miao Shu , Chen Fucun , Zhang Shuang , Liu Zhenni , Xie Sujuan , Xu Longya 
Published: November 2014

AbstractHigh aluminum content constitutes a major hurdle for the postsynthesis modification of hierarchical zeolites. A facile protocol comprising fluorination and sequential alkaline treatment is presented for the postsynthesis modification of hierarchical Al‐rich MFI zeolites. By virtue of this protocol, uniform intracrystalline mesoporosity is introduced in an Al‐rich MFI zeolite (Si/Al=14.3). The obtained hierarchical zeolites exhibit a significant mesopore size distribution, centered around 6 nm, and show improved conversions in catalytic cracking of bulky aromatic molecules. The fundamental implications of the fluorination–alkaline treatment protocol are related to the formation of F‐bearing tetrahedral aluminum species in the antecedent fluorination step, which alleviates the resistance of Al sites to the alkaline medium and causes AlF complexation for regulated hydrolysis of the Al species during the alkaline treatment process. This top‐down protocol and the derived mechanistic understandings are expected to be applied in the synthesis of hierarchical Al‐rich zeolites with other framework topologies.
Nanocomposites of Sulfonic Polyaniline Nanoarrays on Graphene Nanosheets with an Improved Supercapacitor Performance
Authors: Zhao Hai‐Bo , Yang Jun , Lin Ting‐Ting , Lü Qiu‐Feng , Chen Guo 
Published: November 2014

AbstractA new nanocomposite, poly(aniline‐co‐diphenylamine‐4‐sulfonic acid)/graphene (PANISP/rGO), was prepared by means of an in situ oxidation copolymerization of aniline (ANI) with diphenylamine‐4‐sulfonic acid (SP) in the presence of graphene oxide, followed by the chemical reduction of graphene oxide using hydrazine hydrate as a reductant. The morphology and structure of PANISP/rGO were characterized by field‐emission (FE) SEM, TEM, X‐ray photoelectron spectroscopy (XPS), Raman, FTIR, and UV/Vis spectra. The electrochemical performance was evaluated by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The PANISP/rGO nanocomposite showed a nanosized structure, with sulfonic polyaniline nanoarrays coated homogeneously on the surface of graphene nanosheets. This special structure of the nanocomposite also facilitates the enhancement of the electrochemical performance of the electrodes. The PANISP/rGO nanocomposite exhibits a specific supercapacitance up to 1170 F g−1 at the current density of 0.5 A g−1. The as‐prepared electrodes show excellent supercapacitive performance because of the synergistic effects between graphene and the sulfonic polyaniline copolymer chains.
Differences and Comparisons of the Properties and Reactivities of Iron(III)–hydroperoxo Complexes with Saturated Coordination Sphere
Authors: Faponle Abayomi S. , Quesne Matthew G. , Sastri Chivukula V. , Banse Frédéric , de Visser Sam P. 
Published: November 2014

AbstractHeme and nonheme monoxygenases and dioxygenases catalyze important oxygen atom transfer reactions to substrates in the body. It is now well established that the cytochrome P450 enzymes react through the formation of a high‐valent iron(IV)–oxo heme cation radical. Its precursor in the catalytic cycle, the iron(III)–hydroperoxo complex, was tested for catalytic activity and found to be a sluggish oxidant of hydroxylation, epoxidation and sulfoxidation reactions. In a recent twist of events, evidence has emerged of several nonheme iron(III)–hydroperoxo complexes that appear to react with substrates via oxygen atom transfer processes. Although it was not clear from these studies whether the iron(III)–hydroperoxo reacted directly with substrates or that an initial OO bond cleavage preceded the reaction. Clearly, the catalytic activity of heme and nonheme iron(III)–hydroperoxo complexes is substantially different, but the origins of this are still poorly understood and warrant a detailed analysis. In this work, an extensive computational analysis of aromatic hydroxylation by biomimetic nonheme and heme iron systems is presented, starting from an iron(III)–hydroperoxo complex with pentadentate ligand system (L52). Direct CO bond formation by an iron(III)–hydroperoxo complex is investigated, as well as the initial heterolytic and homolytic bond cleavage of the hydroperoxo group. The calculations show that [(L52)FeIII(OOH)]2+ should be able to initiate an aromatic hydroxylation process, although a low‐energy homolytic cleavage pathway is only slightly higher in energy. A detailed valence bond and thermochemical analysis rationalizes the differences in chemical reactivity of heme and nonheme iron(III)–hydroperoxo and show that the main reason for this particular nonheme complex to be reactive comes from the fact that they homolytically split the OO bond, whereas a heterolytic OO bond breaking in heme iron(III)–hydroperoxo is found.
Copper/Silver‐Mediated Direct ortho‐Ethynylation of Unactivated (Hetero)aryl CH Bonds with Terminal Alkyne
Authors: Liu Yue‐Jin , Liu Yan‐Hua , Yin Xue‐Song , Gu Wen‐Jia , Shi Bing‐Feng 
Published: November 2014

AbstractA copper/silver‐mediated oxidative ortho‐ethynylation of unactivated aryl CH bonds with terminal alkyne has been developed. The reaction uses the removable PIP directing group and features broad substrate scope, high functional‐group tolerance, and compatibility with a wide range of heterocycles, providing an efficient synthesis of aryl alkynes. This procedure highlights the potential of copper catalysts to promote unique, synthetically enabling CH functionalization reactions that lie outside of the current scope of precious metal catalysis.
Applications of Lithium‐Containing Hydrides for Energy Storage and Conversion
Authors: Wietelmann Ulrich 
Published: November 2014

AbstractLithium‐containing hydrides and some derivatives are mainly used in synthetic chemistry for the selective reduction of functional groups. Hydrogen storage applications of complex Li hydrides and reactive mixtures with other metal hydrides or amides have been investigated thoroughly, but practical applications are hampered due to limited reversibility and unfavorable conditions for the sorption and desorption of hydrogen. In the field of electrochemical energy storage, complex Li‐containing hydrides are investigated as Li‐ion‐conducting materials and as active materials for anodes of non‐aqueous batteries.
Boosting Activation of Oxygen Molecules on C60 Fullerene by Boron Doping
Authors: Li Qiao‐Zhi , Zheng Jia‐Jia , Dang Jing‐Shuang , Zhao Xiang 
Published: November 2014

AbstractThe activation of oxygen molecules on boron‐doped C60 fullerene (C59B) and the subsequent water formation reaction are systematically investigated by using hybrid density functional calculations. Results indicate that C59B shows a favorable ability to activate oxygen molecules both kinetically and thermodynamically. The oxygen molecule is first adsorbed on the boron atom, which is identified to be the most reactive site in C59B for O2 adsorption because of its high positive charge and spin density. The adsorption structure C59BO2 can further isomerize to form two products with small reaction barriers. Water formation reactions upon these two structures are energetically favorable and suggest a four‐electron mechanism for the oxygen reduction reaction catalyzed by C59B. This work provides a reliable theoretical insight into the catalytic properties of boron‐doped fullerene, which is believed to be helpful to explore fullerene catalysts.
A Full Topological Analysis of Unstable and Metastable Bond Critical Points
Authors: Miorelli Jonathan , Wilson Tim , Morgenstern Amanda , Jones Travis , Eberhart Mark E. 
Published: November 2014

AbstractResearchers are developing conceptually based models linking the structure and dynamics of molecular charge density to certain properties. Here we report on our efforts to identify features within the charge density that are indicative of instability and metastability. Towards this, we use our extensions to the quantum theory of atoms in molecules that capitalize on a molecule’s ridges to define a natural simplex over the charge density. The resulting simplicial complex can be represented at various levels by its 0‐, 1‐, and 2‐skeleton (dependent sets of points, lines, and surfaces). We show that the geometry of thesen‐skeletons retains critical information regarding the structure and stability of molecular systems while greatly simplifying charge density analysis. As an example, we use our methods to uncover the fingerprints of instability and metastability in two much‐discussed systems, that is, the di‐benzene complex and the He and adamantane inclusion complex.
Facile Synthesis of Hierarchical Magnesium Silicate Hollow Nanofibers Assembled by Nanosheets as an Efficient Adsorbent
Authors: Jin Renxi , Yang Yang , Li Yunfeng , Yu Xiaodan , Xing Yan , Song Shuyan , Shi Zhan 
Published: November 2014

AbstractMagnesium silicate double‐walled hollow nanofibers (MSHNFs) with a hierarchical nanostructure have been successfully fabricated by combining the electrospinning technique with a hydrothermal method. The as‐prepared MSHNFs are composed of numerous ultrathin nanosheets with a thickness of approximately 10 nm and have a high specific surface area (632.2 m2 g−1) and large pore volume (0.92 cm3 g−1). The MSHNFs exhibit high adsorption capacity and excellent stability in a purification test with organic molecules and a solution of heavy‐metal ions. Moreover, the MSHNFs can be easily separated from solution by gravitational sedimentation owing to their unique structure.
Variable antenna‐space shift keying for high spectral efficiency in exponentially correlated channels
Authors: Osman Onur 
Published: November 2014

SummaryIn space shift keying (SSK), all information bits are transmitted by antenna indices rather than transmitting symbols. To obtain high spectral efficiency, exponentially increasing number of antennas is used, which is generally not practical. Less number of antennas can only be possible by using more than one active antenna, such as generalized SSK, but this type of solutions result in excessive degradation in bit error ratio in correlated channels. In this study, variable number of active antennas for each codeword is proposed and called variable antenna‐SSK. First of all, pairwise error probability is obtained for variable number of antennas in the case of correlated channels. Then, to reduce the correlation effect, a novel antenna codeword construction method that minimizes the pairwise error probability is introduced for exponentially correlated channels. Codeword sets are obtained for k = 3 and 8 bits/s/Hz for 7 and 13 transmit antennas. Simulation results show that variable antenna‐SSK gets better performance according to its counterparts with increasing effect of correlation. Copyright © 2014 John Wiley & Sons, Ltd.
Syntheses, Crystal Structures and Solid‐State Properties of the Lanthanoid‐Containing Nanoclusters [(Ln2PW10O38)4(W3O8)(OH)4(H2O)2]26–
Authors: Gupta Rakesh , Saini Mukesh Kumar , Hussain Firasat 
Published: November 2014

AbstractA series of lanthanoid‐substituted polyoxometalates have been synthesized by a self‐assembly process in potassium chloride solution by the reaction of dilacunary [P2W19O69(H2O)]14– with mid‐ and late‐lanthanoid Ln(NO3)3·nH2O salts leading to the formation of the tetrameric tungstophosphates [(Ln2PW10O38)4(W3O8)(OH)4(H2O)2]26– [Ln = Y3+ (1), Sm3+ (2), Eu3+ (3), Gd3+ (4), Tb3+ (5), Dy3+ (6), Ho3+ (7), Er3+ (8), Tm3+ (9), Yb3+ (10)]. The polyanions were isolated as potassium or mixed‐alkali salts. Most of the compounds were characterized by single‐crystal X‐ray diffraction and various analytical techniques, such as FTIR, UV/Vis, 31P NMR and photoluminescence spectroscopy, magnetism, as well as thermogravimetric analysis. The FTIR spectra suggest that all the compounds are isomorphous. The crystal structures of these complexes consist of four A‐[α‐PW10O36]7– units, each incorporating two LnIII ions to create four Keggin‐like anions that further assemble with three additional tungstate units to form a tetramer species with C2 symmetry. The photoluminescent properties of 3a and 6a were investigated following photoexcitation at room temperature. The magnetic properties of 3a, 4a, 5a and 6a were investigated at room temperature, the complexes exhibiting paramagnetic behaviour.