bluuebunny/crossref_metadata_2025 huggingface dataset:
Cultivable Microbial Diversity in An Acidic Temperate Lake, Lake Phelps, NC
Authors: Keovilayvong Vongvilay , Lancaster Jeremiah , Fightmaster Christopher , Kahan William , Frontera-Suau Roberto , Abebe Eyualem , Levin Keith , Weber Frank
Published: May 2013

Despite the immense benefit of freshwater habitats to the day to day activities of humans, their biological diversity remains understudied. Microbial diversity and community structure is critical to the study of ecological processes in these habitats. The naturally acidic oligotrophic lake, Lake Phelps, NC, was studied within the context of understanding sediment dwelling meiofauna using the cultivable microbial communities at three sites in the water column and sediment. Twenty-six bacterial isolates were cultivated, biochemically tested and sequenced. DNA sequence analyses of the 16S ribosomal subunit revealed 26 taxa representing three phyla (12 Proteobacteria, 12 Firmicutes, and 2 Bacteroidetes), four classes (12 Bacilli, 6 β-proteobacteria, 4 γ-proteobacteria, and 2 Flavobacteria), and six bacterial orders (12 Bacillales, 6 Neisseriales, 2 Burkholderiales, 4 Enterobacteriales, and 2 Flavobacteriales). Bacterial communities at the three sampling sites were distinct and this may be because of site-specific features. The lake is believed to have been formed from the fusion of two Carolina bays with differing geochemical factors contributing to unique microenvironments. Current studies are in progress to examine associated meiofauna within each microbial community.
The Streptavidin/Biotinylated DNA/Protein Bound Complex Protocol for Determining the Association of c‐JUN Protein with NANOG Promoter
Authors: Ibrahim Elsayed E. , Babaei‐Jadidi Roya , Nateri Abdolrahman S.
Published: May 2013

Chromatin immunoprecipitation (ChIP) is a widely used and pre‐eminent technique for detecting the association of an individual protein or a particular protein complex with its specific DNA sequence(s) in vivo. Herein we introduce a novel and simple biotinylated‐oligonucleotide‐mediated ChIP method for testing specific binding of the c‐JUN protein to the M1‐DNA‐regulatory element in the NANOG promoter. We prepared a 260‐bp DNA PCR amplicon containing −300 bp to −59 bp, relative to the transcriptional start site of the human NANOG gene, which was transfected into mouse embryonic fibroblasts (MEF) containing wild‐type (c‐jun+/+) or knockout c‐jun (c‐jun−/−) alleles. Whole cells that were cross‐linked using formaldehyde and protein‐DNA interactions were immunoprecipitated using streptavidin‐coupled Dynabeads. Protein‐DNA cross‐links were reversed during incubation at 95°C, and protein samples were visualized using SDS‐PAGE electrophoresis and western blotting. This streptavidin/biotinylated DNA/protein‐bound complex protocol can be used for detecting the interactions between multiple transcription factors and their DNA binding sites. Curr. Protoc. Stem Cell Biol. 25:1B.10.1‐1B.10.13. © 2013 by John Wiley & Sons, Inc.
Revealing Neuronal Circuitry Using Stem Cell‐Derived Neurons
Authors: Garcia Isabella , Kim Cynthia , Arenkiel Benjamin R.
Published: May 2013

Mouse embryonic stem cell (mESC)‐derived neurons are a renewable cell source for investigation of neuronal circuits. Engineering circuit‐tracing components into stem cells facilitates studies on mechanisms of synaptic coupling and circuitogenesis. This unit details methods for the generation of mESC‐derived neurons harboring trans‐synaptic viral tracing elements, which are used for investigation of synaptic connections within circuits in vitro, ex vivo, and in vivo. The first protocol describes procedures for feeder‐free passaging of mESCs, modified to carry reporter and rabies virus tracing elements. The second protocol describes in vitro generation of neurons from these ESCs. The last protocols describe the use of ESC‐derived neurons as “source cells” for rabies virus circuit‐tracing to identify inputs onto synaptically connected neurons. Given the broad applicability, these protocols can be applied to investigate the ability of in vitro‐derived neurons to establish/maintain synaptic connections in disease models, and/or with human‐induced pluripotent stem cells. Curr. Protoc. Stem Cell Biol. 25:2D.15.1‐2D.15.18. © 2013 by John Wiley & Sons, Inc.
A new technique for recovering energy in thermally coupled distillation using vapor recompression cycles
Authors: Navarro‐Amorós Miguel A. , Ruiz‐Femenia Rubén , Caballero José A.
Published: May 2013

Even though it has been proved that a fully thermally coupled distillation (TCD) system minimizes the energy used by a sequence of columns, it is well‐known that vapor/liquid transfers between different sections produce an unavoidable excess of vapor (liquid) in some of them, increasing both the investment and operating costs. It is proposed here to take advantage of this situation by extracting the extra vapor/liquid and subjecting it to a direct/reverse vapor compression cycle. This new arrangement restores the optimal operating conditions of some of the affected sections with energy savings of around 20–30% compared with conventional TCD columns. Various examples, including the direct and reverse vapor recompression cycles, are presented. Furthermore, in each example, all possible modes of distillation (direct, indirect and Petlyuk distillation) with and without vapor recompression cycles (VRC) are compared to ensure that this approach delivers the best results. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3767–3781, 2013
Human bulbar conjunctival hemodynamics in hemoglobin SS and SC disease
Authors: Wanek Justin , Gaynes Bruce , Lim Jennifer I. , Molokie Robert , Shahidi Mahnaz
Published: May 2013

The known biophysical variations of hemoglobin (Hb) S and Hb C may result in hemodynamic differences between subjects with SS and SC disease. The purpose of this study was to measure and compare conjunctival hemodynamics between subjects with Hb SS and SC hemoglobinopathies. Image sequences of the conjunctival microcirculation were acquired in 9 healthy control subjects (Hb AA), 24 subjects with SC disease, and 18 subjects with SS disease, using a prototype imaging system. Diameter (D) and blood velocity (V) measurements were obtained in multiple venules of each subject. Data were categorized according to venule caliber by averaging V and D for venules with diameters less than (vessel size 1) or greater than (vessel size 2) 15 µm. V in vessel size 2 was significantly greater than V in vessel size 1 in the AA and SS groups (P ≥ 0.009), but not in the SC group (P = 0.1). V was significantly lower in the SC group as compared to the SS group (P = 0.03). In AA and SS groups, V correlated with D (P ≤ 0.005), but the correlation was not statistically significant in the SC group (P = 0.08). V was inversely correlated with hematocrit in the SS group for large vessels (P = 0.03); however, no significant correlation was found in the SC group (P ≥ 0.2). Quantitative assessment of conjunctival microvascular hemodynamics in SS and SC disease may advance understanding of sickle cell disease pathophysiology and thereby improve therapeutic interventions. Am. J. Hematol. 88:661–664, 2013. © 2013 Wiley Periodicals, Inc.
The effects of market integration on childhood growth and nutritional status: The dual burden of under‐ and over‐nutrition in the Northern Ecuadorian Amazon
Authors: Houck Kelly , Sorensen Mark V. , Lu Flora , Alban Dayuma , Alvarez Kati , Hidobro David , Doljanin Citlali , Ona Ana Isabel
Published: May 2013

Objectives

Market integration is an important source of cultural change exposing indigenous populations to epidemiologic and nutrition transitions. As children and adolescents are biologically sensitive to the health effects of market integration, we examine community variation of anthropometric indicators of nutritional status and growth among a cross‐cultural sample of Kichwa, Shuar, Huaorani, and Cofán indigenous groups in the northern Ecuadorian Amazon.

Methods

We measured height, weight, body mass index (BMI), upper arm circumference, and triceps skinfolds of 186 children and adolescents aged 2 to 18 years from seven communities. Anthropometric z‐scores were calculated based on the National Health and Nutritional Examination Survey. Comparisons were made with this US reference group, along with between community differences to contextually explore the impacts of varying degrees of market integration.

Results

We found a high prevalence of stunting in both boys (40%) and girls (34%). Adiposity increased with age and 40% of girls between 15 and 18 years old were overweight. There were large sex differences in body composition with higher BMI, arm circumference, and triceps skinfolds in adolescent girls. The Kichwa demonstrated the poorest growth outcomes and nutritional stress followed by the Huaorani and Shuar; yet distinctions in under‐ and over‐nutrition were evident within groups.

Conclusion

Market integration is a major factor influencing the developmental and lifestyle mismatch associated with the epidemiologic and nutrition transition in general, and the dual burden pattern of high rates of stunting yet adequate to above average short‐term nutritional status indicators found among indigenous Amazonian populations. Am. J. Hum. Biol. 25:524–533, 2013. © 2013 Wiley Periodicals, Inc.
The velocity of fetal growth is associated with the breadth of the placental surface, but not with the length
Authors: Alwasel Saleh H. , Harrath Abdul‐Halaim , Aljarallah Jamal S. , Abotalib Zeinab , Osmond Clive , Al Omar S.Y. , Thornburg Kent , Barker David J.P.
Published: May 2013

Objectives

Studies of the placenta in pregnancies complicated by pre‐eclampsia have led to the suggestion that tissue along the length and breadth of its surface has different functions. A recent study in Saudi Arabia showed that the body size of newborn babies was related to the breadth of the surface at birth but not to its length. We have now examined whether the association between placental breadth and body size reflects large size of the baby from an early stage of gestation or rapid growth between early and late gestation.

Methods

We studied 230 women who gave birth to singleton babies in King Khalid Hospital, Riyadh, Saudi Arabia. In total, 176 had ultrasound measurements both before 28 weeks and at 28 weeks or later, which we define as early and late gestation. We used these to calculate growth velocities between early and late gestation, which we expressed as the change in standard deviation scores over a 10‐week period.

Results

The breadth of the placental surface was correlated with fetal growth velocity. The correlation coefficients were 0.24 (P = 0.002) for the head circumference, 0.24 (P = 0.001) for the biparietal diameter and 0.34 (P < 0.001) for the abdominal circumference. The length of the surface was not related to fetal growth velocity.

Conclusions

Tissue along the breadth of the placental surface may be more important than tissue along the length in the transfer of nutrients from mother to baby. This may be part of a wider phenomenon of regional differences in function across the placental surface. Am. J. Hum. Biol. 25:534–537, 2013. © 2013 Wiley Periodicals, Inc.
Clinoptilolite particles as a carrier for biocatalysts immobilization: invertase immobilization and characterization
Authors: Bahar Tahsin
Published: May 2013

Clinoptilolite, a natural zeolite, was proposed as a carrier for immobilized biocatalyst systems by polyethyleneimine and glutaraldehyde activation. Invertase (EC 3.2.1.26, beta‐fructofuranosidase) as a model biocatalyst was covalently attached onto the particles by direct chemical reaction between aldehyde groups on the particles and amine groups of the enzyme. The effects of polyethyleneimine concentration, activation agent (glutaraldehyde) concentration, pH and invertase concentration on immobilization process were determined. Approximately 7 mg invertase was immobilized on a gram of clinoptilolite particles with 78% retained activity under optimum immobilization conditions. Immobilization did not affect optimum pH of the enzyme, but it brought out a wider pH–activity curve that was accepted as the indication of better pH stability. Immobilization resulted in an increase at the optimum temperature from 55 to 60 °C. The KM value of immobilized invertase biosystem was found as approximately 1.5 times higher than that of the free enzyme. Immobilization provided improvement on the thermal stability of invertase, and activity half‐life of the immobilized invertase was found as approximately four times longer than that of the free invertase. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation and characterization of phase‐change material nanocapsules with amphiphilic polyurethane synthesized by 3‐allyloxy‐1,2‐propanediol
Authors: Cheng Fangli , Wei Yanyan , Zhang Yingying , Wang Fufang , Shen Tailong , Zong Chengzhong
Published: May 2013

Amphiphilic polyurethane was synthesized with 3‐allyloxy‐1,2‐propanediol as the chain extender, which had an unsaturated double bond for further reaction. It was proven that,with such a structure, the amphiphilic polyurethane not only had good ability for emulsifying phase change materials(PCM) but also was capable of forming a cross‐linked shell. With the amphiphilic polyurethane synthesized in this study, paraffin or methyl stearate nanocapsules in the range of 300–600 nm in size were obtained by a simple high‐speed dispersion and suspension polymerization. No extra emulsifier or dispersant was added during the preparation of the nanocapsules. Tripropylene glycol diacrylate (TPGDA) was used as a crosslinking agent for strengthening nanocapsules. The crosslinking reaction of the shell materials was investigated by the NMR technique. It was found that a network structure of shells was formed after suspension polymerization. Differential scanning calorimetry (DSC) was applied to study the phase change properties of the phase‐change material nanocapsules (PCMNs). The paraffin nanocapsule was found to have a rather high encapsulation efficiency of nearly 100%, and its latent heat was able to reach 104 J/g. Thermogravimetric analysis (TGA) was used to measure the thermal stability of the PCMNs. It was indicated that the weight loss rate of PCMN decreased after encapsulated by polyurethane shells and the weight loss above 200°C decreased after adding the crosslinking agent. All of the PCMN dispersions were found to have rather good dilution stability. Besides, the dried PCMN powder was able to be redispersed into water without any additional emulsifier. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1879–1889, 2013
Formulae for the h‐index: A lack of robustness in Lotkaian informetrics?
Authors: Burrell Quentin L.
Published: May 2013

In one of the first attempts at providing a mathematical framework for the Hirsch index, Egghe and Rousseau (2006) assumed the standard Lotka model for an author's citation distribution to derive a delightfully simple closed formula for his/her h‐index. More recently, the same authors (Egghe & Rousseau, 2012b) have presented a new (implicit) formula based on the so‐called shifted Lotka function to allow for the objection that the original model makes no allowance for papers receiving zero citations. Here it is shown, through a small empirical study, that the formulae actually give very similar results whether or not the uncited papers are included. However, and more important, it is found that they both seriously underestimate the true h‐index, and we suggest that the reason for this is that this is a context—the citation distribution of an author—in which straightforward Lotkaian informetrics is inappropriate. Indeed, the analysis suggests that even if we restrict attention to the upper tail of the citation distribution, a simple Lotka/Pareto‐like model can give misleading results.
Functional Zeolitic‐Imidazolate‐Framework‐Templated Porous Carbon Materials for CO2 Capture and Enhanced Capacitors
Authors: Wang Qingfei , Xia Wei , Guo Wenhan , An Li , Xia Dingguo , Zou Ruqiang
Published: May 2013

Three types of zeolitic imidazolate frameworks (ZIFs) with different topological structures and functional imidazolate‐derived ligands, namely, ZIF‐8, ZIF‐68, and ZIF69, have been directly carbonized to prepare porous carbon materials at 1000 °C. These as‐synthesized porous carbon materials were activated with fused KOH to increase their surface areas and pore volumes for use in gas storage and supercapacitors. The relationship between the local structure of the products and the composition of the precursors has been investigated in detail. The BET surface areas of the resultant activated carbon materials are 2437 (CZIF8a), 1861 (CZIF68a), and 2264 m2 g−1 (CZIF69a). CZIF8a exhibits the highest H2‐storage capacities of 2.59 wt. % at 1 atm and 77 K, whereas CZIF69a has the highest CO2 uptake of 4.76 mmol g−1 at 1 atm and 273 K, owing to its local structure and pore chemical environment. The specific capacities are calculated from the CV curves. CZIF69a exhibits the highest supercapacitor performance of 168 F g−1 at a scan speed of 5 mV s−1. These results indicate that the functional chloride group on the benzimidazolate ligand plays a very important role in improving the surface area, pore volume, and, therefore, CO2‐capture and supercapacitor properties of the corresponding porous carbon materials.
Quantifying Repetitive Speech in Autism Spectrum Disorders and Language Impairment
Authors: van Santen Jan P. H. , Sproat Richard W. , Hill Alison Presmanes
Published: May 2013

We report on an automatic technique for quantifying two types of repetitive speech: repetitions of what the child says him/herself (self‐repeats) and of what is uttered by an interlocutor (echolalia). We apply this technique to a sample of 111 children between the ages of four and eight: 42 typically developing children (TD), 19 children with specific language impairment (SLI), 25 children with autism spectrum disorders (ASD) plus language impairment (ALI), and 25 children with ASD with normal, non‐impaired language (ALN). The results indicate robust differences in echolalia between the TD and ASD groups as a whole (ALN + ALI), and between TD and ALN children. There were no significant differences between ALI and SLI children for echolalia or self‐repetitions. The results confirm previous findings that children with ASD repeat the language of others more than other populations of children. On the other hand, self‐repetition does not appear to be significantly more frequent in ASD, nor does it matter whether the child's echolalia occurred within one (immediate) or two turns (near‐immediate) of the adult's original utterance. Furthermore, non‐significant differences between ALN and SLI, between TD and SLI, and between ALI and TD are suggestive that echolalia may not be specific to ALN or to ASD in general. One important innovation of this work is an objective fully automatic technique for assessing the amount of repetition in a transcript of a child's utterances. Autism Res 2013, ●●: ●●–●●. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.
Effect of glycosylation on the partition behavior of a human antibody in aqueous two‐phase systems
Authors: Lee J.‐W. , Forciniti D.
Published: May 2013

Human proteins are expressed in some hosts wrongly glycosylated or nonglycosylated. Although it is accepted that glycosylation contributes to the stability of the protein in solution, the effect of glycosylation on the stability of human antibodies is not fully understood. In this work, we present solubility studies of two human antibodies that have the same primary structure but different glycosylation pattern. The studies were done by monitoring the partitioning behavior of both proteins in a series of aqueous two‐phase systems at and away the isoelectric point of the proteins and at different temperatures. Our studies show that in the absence of direct electrostatic forces, the partitioning behavior of the antibodies depends on the presence or absence of the polysaccharide chains. Overall, the nonglycosylated protein is less soluble than the glycosylated one. The potential of aqueous two‐phase systems for the separation of the glycosylated and nonglycosylated proteins was also explored. A simple series of extractions seems to be enough to separate the glycosylated variety from the nonglycosylated one at high purity but low yields. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:943–950, 2013
Mass production of spores of lactic acid‐producing Rhizopus oryzae NBRC 5384 on agar plate
Authors: Yamane Tsuneo , Tanaka Ryosuke
Published: May 2013

Mass production of sporangiospores (spores) of Rhizopus oryzae NBRC 5384 (identical to NRRL 395 and ATCC 9363) on potato‐dextrose‐agar medium was studied aiming at starting its L(+)‐lactic acid fermentation directly from spore inoculation. Various parameters including harvest time, sowed spore density, size of agar plate, height of air space, and incubation mode of plate (agar‐on‐bottom or agar‐on‐top) were studied. Ordinarily used shallow Petri dishes were found out to be unsuitable for the full growth of R. oryzae sporangiophores. In a very wide range of the sowed spore density, the smaller it was, the greater the number of the harvested spores was. It was also interesting to find out that R. oryzae grown downward vertically with a deep air space in an agar‐on‐top mode gave larger amount of spores than in an agar‐on‐bottom mode at 30°C for 7‐day cultivation. Scale‐up of the agar plate culture from 26.4 to 292 cm2 was studied, resulting in the proportional relationship between the number of the harvested spores/plate and the plate area in the deep Petri dishes. The number of plates of 50 cm in diameter needed for 100 m3 industrial submerged fermentation started directly from 2 × 105 spores/mL inoculum size was estimated as about 6, from which it was inferred that such a fermentation would be feasible. Designing a 50 cm plate and a method of spreading and collecting the spores were suggested. Bioprocess technological significance of the “full‐scale industrial submerged fermentation started directly from spore inoculation omitting pre‐culture” has been discussed. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:876–881, 2013
Is Fear of Crime Mainly Social and Economic Insecurity in Disguise? A Multilevel Multinational Analysis
Authors: Vieno Alessio , Roccato Michele , Russo Silvia
Published: May 2013

Using the 2006 Eurobarometer data (representative sample of the European population, N = 16 306, 27 countries), we performed a multilevel analysis aimed at predicting fear of crime. A significant proportion of the variation in fear of crime was at country level. Of the individual predictors included, being a woman, being poorly educated, being unemployed, and being an urban dweller showed positive relations with fear of crime. Fear was highest among people who considered themselves to be socially marginal, among people with negative expectations regarding themselves and their country's future, and among people who considered their nation's welfare system to be unsatisfactory. Among the ecological predictors we took into consideration, nations' degree of economic inequality and low expenditure on education and on social protection showed a positive association with fear of crime, whereas the crime, immigration, and employment rates did not. Implications and limitations of this research are discussed. Copyright © 2013 John Wiley & Sons, Ltd.
Gender depended potentiality of differentiation of human umbilical cord mesenchymal stem cells into oocyte‐Like cells in vitro
Authors: Qiu Pubin , Bai Yaofu , Pan Shaohui , Li Wei , Liu Weishuai , Hua Jinlian
Published: May 2013

Recent studies have demonstrated that germ‐like cells could be differentiated from human umbilical cord mesenchymal stem cells (hUC‐MSCs) in vitro. Whether the sexuality of hUC‐MSCs affects the formation efficiency of germ‐like cells derived from hUC‐MSCs is still unclear. To clearly test the formation efficiency of oocyte‐like cells from male and female hUC‐MSCs, obtained hUC‐MSCs were induced by 20% follicular fluid (FF) according to the method that has been proved by our previous studies. Results showed that hUC‐MSCs differentiated into oocyte‐like structures and expressed germ cell makers. It was noted that the presence of advanced oocyte‐like cells in male hUC‐MSCs (m‐hUC‐MSCs) was similar as that in female hUC‐MSCs (f‐hUC‐MSCs); however, the expression of germ cell's specific markers in m‐hUC‐MSCs was delayed compared with that in f‐hUC‐MSCs. In addition, immunofluorescence analysis demonstrated that germ cell–specific markers, Oct4, Vasa, Dazl, ZP2, ZP3 and Stra8, were expressed on the 14th day after induction in both f‐hUC‐MSCs and m‐hUC‐MSCs. However, the size of oocyte‐like cells from f‐hUC‐MSCs was larger than that in m‐hUC‐MSCs. The level of secreted oestradiol was significantly higher in f‐hUC‐MSCs than m‐hUC‐MSCs. We sought to determine whether critical germ cell's transcription factor‐Figlα will promote the development of oocyte‐like cells. Some germ cell–specific markers were increased when exogenous Figlα was transfected into hUC‐MSCs. This process implied that germ‐like cells might be produced by over‐expression of exogenous germ cell–specific gene, and this process was similar as that in production of germ cells in induced pluripotent stem cells (iPSCs). Finally, to verify the feasibility that hUC‐MSCs differentiate into germ cells, hUC‐MSCs were transplanted into seminiferous tubules and kidney capsule of mouse, respectively, and we found the transplanted cells differentiated into germ‐like cells in recipient's seminiferous tubules and kidney capsule. This study will provide a simple model to study mammalian germ cell specification using hUC‐MSCs in vitro. Copyright © 2013 John Wiley & Sons, Ltd.
Highly Reversible Lithium Storage in Hierarchical Ca2Ge7O16 Nanowire Arrays/Carbon Textile Anodes
Authors: Li Wenwu , Wang Xianfu , Liu Bin , Luo Sijun , Liu Zhe , Hou Xiaojuan , Xiang Qingyi , Chen Di , Shen Guozhen
Published: May 2013

Aligned Ca2Ge7O16 nanowire arrays were successfully grown on carbon textiles to form hierarchical 3D structures by using a facile hydrothermal method on a large scale. Typical Ca2Ge7O16 nanowires are single crystals that show preferred growth along the [001] direction. The 3D hierarchical structures were used as binder‐free anodes for lithium‐ion batteries, which showed the features of highly reversible capacity (900–1100 mA h g−1 at a current density of 300 mA g−1), remarkable cycling stability, even over 100 cycles, and good rate capability, with a capacity of about 500 mA h g−1 at 3 A g−1. Furthermore, highly bendable full cells were also fabricated, which showed high flexibility, with little voltage change after bending 600 times, and superior temperature tolerance within the range 4–60 °C, thus demonstrating their promising potential for applications in high‐performance lithium‐ion batteries.
Well‐Defined Molecular Magnesium Hydride Clusters: Relationship between Size and Hydrogen‐Elimination Temperature
Authors: Intemann Julia , Spielmann Jan , Sirsch Peter , Harder Sjoerd
Published: May 2013

A new tetranuclear magnesium hydride cluster, [{NN‐(MgH)2}2], which was based on a NN‐coupled bis‐β‐diketiminate ligand (NN2−), was obtained from the reaction of [{NN‐(MgnBu)2}2] with PhSiH3. Its crystal structure reveals an almost‐tetrahedral arrangement of Mg atoms and two different sets of hydride ions, which give rise to a coupling in the NMR spectrum (J=8.5 Hz). To shed light on the relationship between the cluster size and H2 release, the thermal decomposition of [{NN‐(MgH)2}2] and two closely related systems that were based on similar ligands, that is, an octanuclear magnesium hydride cluster and a dimeric magnesium hydride species, have been investigated in detail. A lowering of the H2‐desorption temperature with decreasing cluster size is observed, in line with previously reported theoretical predictions on (MgH2)n model systems. Deuterium‐labeling studies further demonstrate that the released H2 solely originates from the oxidative coupling of two hydride ligands and not from other hydrogen sources, such as the β‐diketiminate ligands. Analysis of the DFT‐computed electron density in [{NN‐(MgH)2}2] reveals a counterintuitive interaction between two formally closed‐shell H− ligands that are separated by 3.106 Å. This weak interaction could play an important role in H2 desorption. Although the molecular product after H2 release could not be characterized experimentally, DFT calculations on the proposed decomposition product, that is, the low‐valence tetranuclear Mg(I) cluster [(NN‐Mg2)2], predict a structure with two almost‐parallel, localized MgMg bonds. As in a previously reported β‐diketiminate MgI dimer, the MgMg bond is not characterized by a bond critical point, but instead displays a local maximum of electron density midway between the atoms, that is, a non‐nuclear attractor (NNA). Interestingly, both of the NNAs in [(NN‐Mg2)2] are connected through a bond path that suggests that there is bonding between all four MgI atoms.
Uncertainty, mood states, and symptom distress in patients with primary brain tumors
Authors: Lin Lin , Chiang Hui‐Hsun , Acquaye Alvina A. , Vera‐Bolanos Elizabeth , Gilbert Mark R. , Armstrong Terri S.
Published: May 2013

BACKGROUND

Patients with primary brain tumors (PBTs) face uncertainty related to prognosis, symptoms, treatment response, and toxicity. The authors of this report examined the direct/indirect relations among patients' uncertainty, mood states, and symptoms.

METHODS

In total, 186 patients with PBTs were accrued at various points in the illness trajectory. Data‐collection tools included an investigator‐completed clinician checklist, a patient‐completed demographic data sheet, the Mishel Uncertainty in Illness Scale‐Brain Tumor Form (MUIS‐BT), the MD Anderson Symptom Inventory‐Brain Tumor Module (MDASI‐BT), and the Profile of Mood States‐Short Form (POMS‐SF). Structural equation modeling was used to explore correlations among variables.

RESULTS

Participants were primarily white (80%) men (53%) with a variety of brain tumors. They ranged in age from 19 to 80 years (mean ± standard deviation, 44.2 ± 12.6 years). Lower functional status and earlier point in the illness trajectory were associated with greater uncertainty (P < .01 for both). Uncertainty (P < .05), except in the model of “confusion,” and the 5 negative mood states measured by the POMS‐SF were directly associated with symptom severity perceived by patients (P < .01 for all). The impact of uncertainty on perceived symptom severity also was mediated significantly by mood states.

CONCLUSIONS

The results from the study clearly demonstrated distinct pathways for the relations between uncertainty‐mood states‐symptom severity for patients with PBTs. Uncertainty in patients with PBTs is higher for those who have a poor performance status and directly impacts negative mood states, which mediate patient‐perceived symptom severity. This conceptual model suggests that interventions designed to reduce uncertainty or that target mood states may help lessen patients' perception of symptom severity, which, in turn, may result in better treatment outcomes and quality of life. Cancer 2013;119:2796–2806. © 2013 American Cancer Society.
Pemetrexed versus erlotinib in pretreated patients with advanced non–small cell lung cancer: A Hellenic Oncology Research Group (HORG) randomized phase 3 study
Authors: Karampeazis Athanasios , Voutsina Alexandra , Souglakos John , Kentepozidis Nikos , Giassas Stelios , Christofillakis Charalambos , Kotsakis Athanasios , Papakotoulas Pavlos , Rapti Ageliki , Agelidou Maria , Agelaki Sofia , Vamvakas Lambros , Samonis George , Mavroudis Dimitris , Georgoulias Vassilis
Published: May 2013

BACKGROUND

In this superiority study, pemetrexed was compared with erlotinib in pre‐treated patients with metastatic non–small cell lung cancer (NSCLC).

METHODS

Patients with stage IIIB/IV NSCLC who progressed after first‐line or second‐line treatment were randomized to receive either pemetrexed or erlotinib. In total, 21.7% of patients in the pemetrexed arm and 23.5% of patients in the erlotinib arm had squamous cell histology, and treatment was third line in 39.2% and 46.4% of patients, respectively. The primary study endpoint was time to tumor progression (TTP). Epidermal growth factor receptor/v‐Ki‐ras2 Kirsten rat sarcoma viral oncogene homolog (EGFR/KRAS) mutation status also was investigated.

RESULTS

There was no difference in terms of the TTP (P = .195), the objective response rate (P = .469), or overall survival (P = .986) between the 2 treatment arms. In patients who had squamous cell histology, erlotinib resulted in a superior TTP compared with pemetrexed (4.1 months vs 2.5 months, respectively; P = .006). The incidence of grade 3 and 4 neutropenia, thrombocytopenia, and asthenia was significantly higher in the pemetrexed arm, whereas the incidence of grade 3 and 4 skin rash was higher in the erlotinib arm.

CONCLUSIONS

Both pemetrexed and erlotinib had comparable efficacy in pre‐treated patients with metastatic NSCLC, and the current results indicated that genotyping of tumor cells may have an important effect on treatment efficacy. Cancer 2013;119:2754–2764. © 2013 American Cancer Society.
Neurocircuit function in eating disorders
Authors: Friederich Hans‐Christoph , Wu Mudan , Simon Joe J. , Herzog Wolfgang
Published: May 2013

Objective:

Eating disorders are serious psychosomatic disorders with high morbidity and lifetime mortality. Inadequate response to current therapeutic interventions constitutes a challenging clinical problem. A better understanding of the underlying neurobiological mechanisms could improve psychotherapeutic and drug treatment strategies.

Method:

A review highlighting the current state of brain imaging in eating disorders related to the anxiety and pathological fear learning model of anorexia nervosa (AN) and the impulsivity model of binge eating in bulimia nervosa (BN).

Results:

Available neuroimaging studies in patients with acute AN primarily suggest a hyper‐responsive emotional and fear network to food, but not necessarily to eating disorder‐unrelated, salient stimuli. Furthermore, patients with AN show decreased activation in the ventral fronto‐striatal circuits during the performance of a cognitive flexibility task. Results in patients with BN primarily suggest a hypo‐responsive reward system to food stimuli, especially to taste reward. Additionally, patients with BN exhibit impaired brain activation in the inhibitory control network during the performance of general response–inhibition tasks.

Discussion:

Anxiety and pathological fear learning may lead to conditioned neural stimulus‐response patterns to food stimuli and increased cognitive rigidity, which could account for the phobic avoidance of food intake in patients with acute AN. However, further neurobiological studies are required to investigate pathological fear learning in patients with AN. Patients with BN may binge eat to compensate for a hypo‐responsive reward system. The impaired brain activation in the inhibitory control network may facilitate the loss of control over food intake in patients with BN. © 2013 by Wiley Periodicals, Inc. (Int J Eat Disord 2013; 46:425–432)
Cognitive remediation therapy for anorexia nervosa: Current evidence and future research directions
Authors: Tchanturia Kate , Lloyd Samantha , Lang Katie
Published: May 2013

No abtsract.
Closing the “know‐do” gap: training public health professionals in eating disorders prevention via case‐method teaching
Authors: Austin S. Bryn , Sonneville Kendrin R.
Published: May 2013

Expansion of our societies' capacity to prevent eating disorders will require strategic integration of the topic into the curricula of professional training programs. An ideal way to integrate new content into educational programs is through the case‐method approach, a teaching method that is more effective than traditional teaching techniques. The Strategic Training Initiative for the Prevention of Eating Disorders has begun developing cases designed to be used in classroom settings to engage students in topical, high‐impact issues in public health approaches to eating disorders prevention and screening. Dissemination of these cases will provide an opportunity for students in public health training programs to learn material in a meaningful context by actively applying skills as they are learning them, helping to bridge the “know‐do” gap. The new curriculum is an important step toward realizing the goal that public health practitioners be fully equipped to address the challenge of eating disorders prevention. © 2013 by Wiley Periodicals, Inc. (Int J Eat Disord 2013; 46:533–537)
Renewable Pencil Electrodes for Highly Sensitive Anodic Stripping Voltammetric Determination of 3‐Hydroxyflavone and Morin in Bulk Form and in Biological Fluids
Authors: Temerk Yassein M. , Ibrahim Mohamed S. , Kotb Mohammed , Schuhmann Wolfgang
Published: May 2013

An electrochemical anodic adsorptive stripping procedure for ultra‐trace assay of 3‐hydroxyflavone (3HF) and Morin at a renewable pencil electrode (PGE) in bulk form and in biological fluids is described. The nature of the oxidation process of 3HF and Morin taking place at the PGE was characterized by cyclic voltammetry. The results show that the determination of the oxidation peak current is the basis of a simple, accurate and rapid method for quantification of 3HF by square‐wave anodic stripping voltammetry. Determination of Morin was achieved by square‐wave anodic adsorptive stripping voltammetry of the formed MorinCu(II) complex at a PGE. Factors influencing the trace measurements of 3HF and the MorinCu (II) complex at a PGE are assessed. The limits of detection and quantitation for the determination of 3HF and Morin in bulk form and in biological fluids were determined. The statistical analysis and the calibration curve data for trace determination of 3HF and Morin are reported.
Determination of Paracetamol in Presence of Ascorbic Acid in Pharmaceutical Products by Scanning Electrochemical Microscopy
Authors: Lima Alex S. , Meloni Gabriel N. , Bertotti Mauro
Published: May 2013

The selective amperometric determination of paracetamol in pharmaceutical formulations containing ascorbate was achieved by removing the interfering species in the diffusion layer created between a platinum substrate and a disc microelectrode in a Scanning Electrochemical Microscopy (SECM) configuration, while the target analyte was kept unconsumed. After complete depletion of ascorbate, paracetamol was detected at the SECM tip in a free‐interference solution zone. The influence of the substrate potential and the gap distance on the efficiency of ascorbate removal was systematically examined. The effectiveness of the device towards the determination of paracetamol in pharmaceutical samples was evaluated and under optimal conditions the results obtained agreed well with the labeled value.
Electrochemical DNA Biosensor Based on Partially Reduced Graphene Oxide Modified Carbon Ionic Liquid Electrode for the Detection of Transgenic Soybean A2704‐12 Gene Sequence
Authors: Sun Wei , Zhang Yuanyuan , Hu Anhui , Lu Yongxi , Shi Fan , Lei Bingxin , Sun Zhenfan
Published: May 2013

In this work a partially reduced graphene oxide (p‐RGO) modified carbon ionic liquid electrode (CILE) was prepared as the platform to fabricate an electrochemical DNA sensor, which was used for the sensitive detection of target ssDNA sequence related to transgenic soybean A2704‐12 sequence. The CILE was fabricated by using 1‐butylpyridinium hexafluorophosphate as the binder and then p‐RGO was deposited on the surface of CILE by controlling the electroreduction conditions. NH2 modified ssDNA probe sequences were immobilized on the electrode surface via covalent bonds between the unreduced oxygen groups on the p‐RGO surface and the amine group at the 5′‐end of ssDNA, which was denoted as ssDNA/p‐RGO/CILE and further used to hybridize with the target ssDNA sequence. Methylene blue (MB) was used as electrochemical indicator to monitor the DNA hybridization. The reduction peak current of MB after hybridization was proportional to the concentration of target A2704‐12 ssDNA sequences in the range from 1.0×10−12 to 1.0×10−6 mol/L with a detection limit of 2.9×10−13 mol/L (3σ). The electrochemical DNA biosensor was further used for the detection of PCR products of transgenic soybean with satisfactory results.
REGIONAL DISPARITIES IN SELF‐REPORTED HEALTH: EVIDENCE FROM CHINESE OLDER ADULTS
Authors: Mu Ren
Published: May 2013

Despite the subjectivity inherent in individuals' interpretation of good health, self‐reported health is widely used in health‐related studies. With data from the pilot survey of the new China Health and Retirement Longitudinal Study, this paper applies the vignette method to control for differences in individual response scales and examines regional differences in self‐reported health among the elderly in China. The results show that people in different provinces seem to use different criteria when assessing their health conditions. Regional health disparities are underestimated if differentials in response scales are not accounted for. A substantial share of the disparities cannot be explained by the observed differences in respondents' chronic health condition, demographic characteristics, and household wealth, a finding confirmed by a test based on inpatient‐care information. Copyright © 2013 John Wiley & Sons, Ltd.
The response of the dayside equatorial electrojet to step‐like changes of IMF BZ
Authors: Ohtani S. , Uozumi T. , Kawano H. , Yoshikawa A. , Utada H. , Nagatsuma T. , Yumoto K.
Published: May 2013

The equatorial electrojet (EEJ) is driven by zonal electric fields, which are known to be well correlated with the interplanetary electric field and therefore with the interplanetary magnetic field (IMF) BZ component. In the present study, we investigate how the equatorial H magnetic component, and therefore the EEJ, responds to step‐like changes of IMF BZ. The reduction of southward IMF BZ (northward turning) and that of northward IMF BZ (southward turning) are examined separately. The result shows that for the northward turnings, the EEJ immediately starts to weaken with the accuracy of the estimates of the travel times of the IMF changes. The time constant of the response is much longer, and the equatorial H component decreases continuously by 40 nT for 30 min after the northward turnings. In contrast, the response of the EEJ to the southward turnings is far less clear in both magnitude and timing, and it does not depend on whether or not IMF BZ actually becomes southward. The difference in the EEJ response to the northward and southward turnings reflects at least partially the fact that the magnetosphere‐ionosphere system is more sensitive to IMF BZ when IMF is southward than northward. It is suggested that the electric field penetrates from the polar region to the dip equator through a global current system that connects the auroral electrojets and the EEJ, and the ionospheric conductance in the polar region may play an important role in the formation of such a current system.
Quasi‐steady, marginally unstable electron cyclotron harmonic wave amplitudes
Authors: Zhang Xiaojia , Angelopoulos Vassilis , Ni Binbin , Thorne Richard M. , Horne Richard B.
Published: May 2013

Electron cyclotron harmonic (ECH) waves have long been considered a potential driver of diffuse aurora in Earth's magnetotail. However, the scarcity of intense ECH emissions in the outer magnetotail suggests that our understanding of the amplification and the relative importance of these waves for electron scattering is lacking. We conduct a comprehensive study of wave growth and quasi‐linear diffusion to estimate the amplitude of loss‐cone‐driven ECH waves once diffusion and growth balance but before convection or losses alter the background hot plasma sheet population. We expect this to be the most common state of the plasma sheet between episodes of fast convection. For any given wave amplitude, we model electron diffusion caused by interaction with ECH waves using a 2‐D bounce‐averaged Fokker‐Planck equation. After fitting the resultant electron distributions as a superposition of multicomponent subtracted bi‐Maxwellians, we estimate the maximum path‐integrated gain using the HOTRAY ray‐tracing code. We argue that the wave amplitude during quasi‐steady state is the inflection point on a gain‐amplitude curve. During quasi‐steady state, ECH wave amplitudes can be significant (~1 mV/m) at L ~ 8 but drop to very low values (<~0.1 mV/m) in the outer magnetotail (L ~ 16) and likely fall below the sensitivity of typical instrumentation relatively close to Earth mainly because of the smallness of the loss cone. Our result reinforces the potentially important role of ECH waves in driving diffuse aurora and suggests that careful comparison of theoretical wave amplitude estimates and observations is required for resolving the equatorial scattering mechanism of diffuse auroral precipitation.
Antarctic contribution to sea level rise observed by GRACE with improved GIA correction
Authors: Ivins Erik R. , James Thomas S. , Wahr John , O. Schrama Ernst J. , Landerer Felix W. , Simon Karen M.
Published: May 2013

Antarctic volume changes during the past 21 thousand years are smaller than previously thought, and here we construct an ice sheet history that drives a forward model prediction of the glacial isostatic adjustment (GIA) gravity signal. The new model, in turn, should give predictions that are constrained with recent uplift data. The impact of the GIA signal on a Gravity Recovery and Climate Experiment (GRACE) Antarctic mass balance estimate depends on the specific GRACE analysis method used. For the method described in this paper, the GIA contribution to the apparent surface mass change is re‐evaluated to be +55±13 Gt/yr by considering a revised ice history model and a parameter search for vertical motion predictions that best fit the GPS observations at 18 high‐quality stations. Although the GIA model spans a range of possible Earth rheological structure values, the data are not yet sufficient for solving for a preferred value of upper and lower mantle viscosity nor for a preferred lithospheric thickness. GRACE monthly solutions from the Center for Space Research Release 04 (CSR‐RL04) release time series from January 2003 to the beginning of January 2012, uncorrected for GIA, yield an ice mass rate of +2.9± 29 Gt/yr. The new GIA correction increases the solved‐for ice mass imbalance of Antarctica to −57±34 Gt/yr. The revised GIA correction is smaller than past GRACE estimates by about 50 to 90 Gt/yr. The new upper bound to the sea level rise from the Antarctic ice sheet, averaged over the time span 2003.0–2012.0, is about 0.16±0.09 mm/yr.