bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel method for monitoring tumor proliferation in vivo using fluorescent dye DiD
Authors: Yumoto Kenji , Berry Janice E. , Taichman Russell S. , Shiozawa Yusuke
Published: April 2014

Monitoring single cell proliferation in vivo is difficult, but optimizing this technique is essential in order to expand our knowledge of the regulation of tumor proliferation. In this study, we used a lipophilic fluorescent dye, DiD, that rapidly and stably integrates into the phospholipid cell membrane. We cultured DiD‐stained prostate cancer cell lines for 10 days and isolated cells by flow cytometry based on expression levels of DiD. We found that a decrease in DiD intensity was correlated to the reduction of EdU, where the DiD‐high population proliferated more slowly than the DiD‐low population and the DiD‐low population exhibited a higher mitotic index. We also found that DiD was detected after 3 weeks of implantation in an in vivo setting. Importantly, DiD dye did not have any effect on normal cell growth, whereas a gold standard fluorescent dye for measuring cell proliferation, CFSE, slowed cell proliferation. Although further study is indicated, DiD can be useful for identifying the molecular mechanisms underlying tumor proliferation in vivo. © 2014 International Society for Advancement of Cytometry
Sialylation may be dispensable for reciprocal modulation of helper T cells by intravenous immunoglobulin
Authors: Othy Shivashankar , Topçu Selma , Saha Chaitrali , Kothapalli Prathap , Lacroix‐Desmazes Sebastien , Käsermann Fabian , Miescher Sylvia , Bayry Jagadeesh , Kaveri Srini V.
Published: April 2014

Several mechanisms account for the beneficial effect of intravenous immunoglobulin (IVIg) in autoimmune and inflammatory diseases. These mechanisms include effects on the cellular compartment and on the humoral compartment. Thus, IVIg impacts on dendritic cells, macrophages, neutrophils, basophils, NK cells, and B and T lymphocytes. Several studies have emphasized that the antiinflammatory effect of IVIg is dependent on α2,6‐sialylation of the N‐linked glycan on asparagine‐297 of the Fc portion of IgG. However, recent reports have questioned the necessity of sialylated Fc and the role of FcγRIIB in IVIg‐mediated antiinflammatory effects. In view of the critical role played by Th17 cells in several autoimmune pathologies and the increasing use of IVIg in several of these conditions, by using neuraminidase‐treated, desialylated IVIg, we addressed whether the α2,6‐sialylation of IgG is essential for the beneficial effect of IVIg in experimental autoimmune encephalomyelitis (EAE), a Th17‐driven condition, and for the reciprocal modulation of helper T‐cell subsets. We observed no difference in the ability of IVIg to ameliorate EAE irrespective of its sialylation. Our findings thus show that sialylation of IVIg is not necessary for IVIg‐mediated amelioration of EAE or for downregulation of Th17 cells and upregulation of regulatory T cells.
Neutral Hexacoordinate Silicon(IV) Complexes with a Tridentate Dianionic O,N,X Ligand (X = O, N, S), Bidentate Monoanionic X,N Ligand (X = O, S), and Phenyl Ligand: Compounds with a SiO3N2C, SiSO2N2C, SiO2N3C, SiSON3C, or SiS2ON2C Skeleton
Authors: Weiß Jörg , Baus Johannes A. , Burschka Christian , Tacke Reinhold
Published: April 2014

A series of neutral hexacoordinate silicon(IV) complexes (4a, 4b, 5a, 5b, 6a, and 6b) with a SiO3N2C, SiSO2N2C, SiO2N3C, SiSON3C, or SiS2ON2C skeleton have been synthesized and structurally characterized by solid‐state and solution NMR spectroscopy and single‐crystal X‐ray diffraction. These studies were performed with a special emphasis on comparing the respective O/NMe/S analogues 4a/5a/6a and 4b/5b/6b and the O/S pairs 4a/4b, 5a/5b, and 6a/6b with respect to their structures and NMR spectroscopic parameters.
1‐Methyl‐5‐(trifluoromethyl)azafulvenium Methide, an Intermediate That Undergoes Reaction through “Unusual” cis‐exo‐1,3‐ and trans‐exo‐1,7‐Cycloadditions
Authors: Peláez Walter José , Pepino Ana Julieta , Argüello Gustavo Alejandro , Pinho e Melo Teresa M. V. D.
Published: April 2014

The generation and reactivity of a new 1‐methyl‐5‐(trifluoromethyl)azafulvenium methide are described. Under microwave‐induced pyrolysis conditions this intermediate could be trapped by dipolarophiles, acting either as a 4π or as an 8π dipole. Quantum chemical calculations carried out at the DFT level of theory allowed the rationalization of the results observed in the cycloaddition of 1‐methyl‐5‐(trifluoromethyl)azafulvenium methide and N‐substituted maleimides. The study revealed that for 1,7‐cycloadducts the major products are obtained in the trans configuration through the unusual exo‐cycloaddition mode, whereas for 1,3‐cycloadducts the cis counterparts are obtained from this unexpected approach. In addition, under flash vacuum pyrolysis or conventional thermolysis conditions 1‐methyl‐5‐(trifluoromethyl)azafulvenium methide undergoes an allowed suprafacial sigmatropic [1,8]H shift leading to the formation of 2‐methyl‐3‐(trifluoromethyl)‐1‐vinyl‐1H‐pyrrole.
Effect of Electrostatic Interaction on Electrodeposition of Nickel Hexacyanoferrate with Functional MWCNTs and Their Application for the Determination of Persulfate and Tannic Acid
Authors: Tsai Tsung‐Hsuan , Yeh Pin‐Chun , Chen Shen‐Ming , Ali M. Ajmal , Al‐Hemaid Fahad M. A.
Published: April 2014

A nanocomposite film of NiHCF electrodeposited onto AFCNT was modified on GCE by the electrostatic interaction of multiple scan cyclic voltammetry. Amino groups have been introduced with a positive charge onto the surface of MWCNTs. The presence of NiHCF‐AFCNT/GCE was characterized by using FE‐SEM, EDS, EIS, and XRD studies. The nanocomposite film of NiHCF‐AFCNT was further utilized to determine persulfate and tannic acid, respectively. The nanocomposite film modified electrode displays linear response from 0.1 to 19 mM and 10 to 170 µM for persulfate and tannic acid with a correlation coefficient of 0.9921 and 0.9869. The detection limits were found to be 0.1 mM and 1 µM, respectively. As results, the electrostatic interaction between positively charged metal ions, amino functionalized CNT and negatively charged hexacyanoferrate can be a new subject for many interesting applications.
Alzheimer Disease Biomarker Detection Through Electrocatalytic Water Oxidation Induced by Iridium Oxide Nanoparticles
Authors: Rivas Lourdes , de la Escosura‐Muñiz Alfredo , Pons Josefina , Merkoçi Arben
Published: April 2014

Iridium oxide nanoparticles (IrO2 NPs) synthesized following a previously reported chemical route are presented as novel tags for immunosensing taking advantage of their electrocatalytic activity towards water oxidation reaction (WOR). Cyclic voltammetry and chronoamperometry for the evaluation of the IrO2 NPs electrocatalytic activity towards WOR at neutral pH were used. The chronoamperometric current recorded at a fixed potential of +1.3 V constituted the analytical signal allowing the quantification of IrO2 NPs at nM levels. Modification of the surface of citrate‐capped IrO2 NPs with anti‐Apolipoprotein E antibodies (αApoE) was successfully achieved and the as‐prepared conjugates were used for the electrocatalytic detection of ApoE Alzheimer disease (AD) biomarker in a magnetosandwich immunoassay, reaching a detection limit of 68 ng/mL. Human plasma of a patient suffering AD was also evaluated, estimating an ApoE concentration of 20 µg/mL which is in concordance with the obtained in previously reported approaches. This novel IrO2 NPs based electrocatalytic assay presents the advantage of the signal generation in the same medium where the immunoassay takes place (PBS, pH 7.4) avoiding the use of additional reagents which also opens the way to future integrated biosensing systems and platforms with interest for other proteins as well as DNA and cells analysis.
Surprise beyond prediction error
Authors: Chumbley Justin R. , Burke Christopher J. , Stephan Klaas E. , Friston Karl J. , Tobler Philippe N. , Fehr Ernst
Published: April 2014

Surprise drives learning. Various neural “prediction error” signals are believed to underpin surprise‐based reinforcement learning. Here, we report a surprise signal that reflects reinforcement learning but is neither un/signed reward prediction error (RPE) nor un/signed state prediction error (SPE). To exclude these alternatives, we measured surprise responses in the absence of RPE and accounted for a host of potential SPE confounds. This new surprise signal was evident in ventral striatum, primary sensory cortex, frontal poles, and amygdala. We interpret these findings via a normative model of surprise. Hum Brain Mapp 35:4805–4814, 2014. © 2014 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc.
The Volume‐Outcome Relationship and Minimum Volume Standards – Empirical Evidence for Germany
Authors: Hentschker Corinna , Mennicken Roman
Published: April 2014

For decades, there is an ongoing discussion about the quality of hospital care leading i.a. to the introduction of minimum volume standards in various countries. In this paper, we analyze the volume‐outcome relationship for patients with intact abdominal aortic aneurysm and hip fracture. We define hypothetical minimum volume standards in both conditions and assess consequences for access to hospital services in Germany. The results show clearly that patients treated in hospitals with a higher case volume have on average a significant lower probability of death in both conditions. Furthermore, we show that the hypothetical minimum volume standards do not compromise overall access measured with changes in travel times. Copyright © 2014 John Wiley & Sons, Ltd.
Pelvic floor muscle dysfunctions are prevalent in female chronic pelvic pain: A cross‐sectional population‐based study
Authors: Loving S. , Thomsen T. , Jaszczak P. , Nordling J.
Published: April 2014

Background

No current standardized set of pelvic floor muscle (PFM) outcome measures have been specifically tested for their applicability in a general female chronic pelvic pain (CPP) population. We aimed to compare PFM function between a randomly selected population‐based sample of women with CPP and age‐matched pain‐free controls using multiple standardized intravaginal examination measures recommended by the International Continence Society.

Methods

This was a cross‐sectional, population‐based and controlled study with randomly selected participants among women in Denmark. We reported blinded findings from a set of standardized vaginal PFM examination manoeuvres in 50 female participants (24 with CPP, 26 pain free). A preliminary pilot study ensured the intra‐ and intertester reliability of the test procedure. PFM outcomes were resting tone, relaxation capacity, strength, surface electromyographic activity and mechanosensitivity. Statistical analyses included unpaired t‐tests, Fisher's exact tests and Mann–Whitney tests.

Results

The examination protocol was a reliable and predictable clinical measurement of associated PFM dysfunction in female CPP. Women with CPP had higher PFM resting tone and decreased maximal PFM strength and relaxation capacity compared with pain‐free controls. Enhanced PFM pressure‐pain sensitivity measured by palpometry during examination was also associated to CPP.

Conclusion

This controlled, single‐blinded study with randomly selected participants provides new population‐based information regarding associated PFM dysfunction in women with CPP using multiple intravaginal examination methods. However, to identify women with CPP who will benefit from a physiotherapeutic specialized intervention, future prospective randomized controlled trials using these reliable and predictive outcomes are needed.
Evidence for central sensitization in patients with osteoarthritis pain: A systematic literature review
Authors: Lluch E. , Torres R. , Nijs J. , Van Oosterwijck J.
Published: April 2014

Hyperexcitability of the central nervous system (CNS) has been suggested to play an important role in the chronic pain experienced by osteoarthritis (OA) patients. A systematic review followingPRISMAguidelines was performed to evaluate the existing evidence from the literature related to the presence of central sensitization (CS) in patients withOA.Electronic databases PubMed and Web of Science were searched to identify relevant articles using pre‐defined keywords regardingCSandOA. Full‐text clinical reports addressing studies ofCSin human adults with chronic complaints due to osteoarthritis were included and screened for methodological quality by two independent reviewers. From the 40 articles that were initially eligible for methodological quality assessment, 36 articles achieved sufficient scores and therefore were discussed. The majority of these studies were case–control studies and addressedOAof the knee joint. Different subjective and objective parameters considered manifestations ofCS, which have been previously reported in other chronic pain conditions such as whiplash or rheumatoid arthritis, were established in subjects withOApain. Overall results suggest that, although peripheral mechanisms are involved inOApain, hypersensitivity of theCNSplays a significant role in a subgroup of subjects within this population. Although the majority of the literature provides evidence for the presence ofCSin chronicOApain, clinical identification and treatment ofCSinOAis still in its infancy, and future studies with good methodological quality are necessary.
Targeting of EGF‐displayed protein nanoparticles with anticancer drugs
Authors: Matsumoto Rie , Hara Rieko , Andou Takashi , Mie Masayasu , Kobatake Eiry
Published: April 2014

The development of protein‐based carriers for drug delivery has been well studied. We previously constructed a protein‐based nanoparticle consisting of genetically engineered elastin‐like polypeptides (ELPs) with a fused poly‐aspartic acid tail (ELPD). The size of the self‐assembled ELPD nanoparticles was regulated by charged repulsion of the poly‐aspartic acid chains. In the present study, epidermal growth factor (EGF) was genetically fused to the C‐terminus of ELPD to impart an active targeting ability to the ELPD nanoparticles. We examined the nanoparticle formation with EGF as well as its targeting ability. ELPD with fused EGF was found to form nanoparticles that displayed multivalent EGFs on their surface. EGF‐displayed nanoparticles loaded with the anti‐cancer drug paclitaxel were internalized into cells overexpressing the EGF receptor, and induced cell death. © 2014 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 102B: 1792–1798, 2014.
Synthesis, characterization and in vitro evaluation of cytotoxicity and antimicrobial activity of chitosan–metal nanocomposites
Authors: Kaur Pawan , Thakur Rajesh , Barnela Manju , Chopra Meenu , Manuja Anju , Chaudhury Ashok
Published: April 2014

BACKGROUND

The present study explores the synthesis of chitosan–metal nanocomposites in view of their increasing application as antimicrobial material.

RESULTS

Chitosan nanoparticles were prepared by ionic gelation between chitosan and sodium tripolyphosphate. Copper sulphate hydrate (CuSO4.5H2O) and zinc acetate (Zn (O2CCH3)2) were used as precursors for synthesis of chitosan–copper nanocomposites (Cu/Ch) and chitosan–zinc nanocomposites (Zn/Ch), respectively. Synthesis of nanocomposites was confirmed by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy with energy dispersive X‐ray microanalyses (SEM‐EDX) and differential scanning calorimetry (DSC). Cytotoxicity of nanoformulations was studied by Resazurin assay on Vero cell line (African green monkey kidney cell line). Their antibacterial activities were assessed by the zone of inhibition method and time dependent growth curve against Micrococcus luteus MTCC 1809, Pseudomonas aeruginosa MTCC 424 and Salmonella enterica MTCC 1253 in vitro. Antifungal activity was also studied against Alternaria alterneta, Rhizoctonia solani and Aspergillus flavus in vitro by the mycelium inhibition method.

CONCLUSIONS

It was observed that all nanoformulations show high antimicrobial activity against all test microorganisms. So chitosan–metal complexes could be promising candidates for novel antimicrobial agents in cosmetic, food and textile industries. © 2014 Society of Chemical Industry
Investigation of selective arabinose release from corn fibre by acid hydrolysis under mild conditions
Authors: Fehér Csaba , Gazsó Zita , Tatijarern Patomwat , Molnár Máté , Barta Zsolt , Réczey Kati
Published: April 2014

BACKGROUND

The high cost of pure arabinose has resulted in a growing demand to develop new cost‐effective methods of arabinose production from lignocellulosic and pectin‐rich materials. Corn fibre is an inexpensive by‐product of the corn wet‐milling process, and is a promising raw material for producing arabinose and other value‐added products. In this study fast dilute sulphuric acid hydrolysis of corn fibre was investigated for selective arabinose solubilization. Acid concentration and reaction time of hydrolysis of destarched ground corn fibre and raw corn fibre were 0.25–5 w/w% at 5–15 min and 0.25–1.25 w/w% at 25–75 min, respectively. Results were evaluated statistically and model equations were developed to predict the yields of sugars.

RESULTS

In the case of raw corn fibre the most favourable conditions were 1.1 w/w% sulphuric acid concentration and 51 min reaction time at 90°C, where a total arabinose yield of 75.9% was achieved with satisfactory selectivity. In the case of destarched ground corn fibre at a sulphuric acid concentration of 4.6 w/w%, a reaction time of 5 min and a temperature of 90°C, a total arabinose yield of 80.5% could be achieved with satisfactory selectivity, according to the model equations.

CONCLUSION

Arabinose‐rich liquid fractions were produced by mild sulphuric acid treatments of corn fibre. Based on the models developed the mono‐ and oligosaccharide contents of the hydrolysates can be controlled under the conditions investigated. © 2014 Society of Chemical Industry
Acupressure magnets: A possible MRI hazard
Authors: Otjen Jeffrey P. , Mallon Kara , Brown Julie C.
Published: April 2014

The use of magnets as a component of complementary and alternative medicine is increasingly common. Magnet therapy is used to treat a variety of conditions and often involves tiny magnets adhered to the skin. In auriculotherapy, magnets are placed in specific locations of the ear pinnae which represent particular parts of the body. While generally considered safe, these magnets have the potential to cause imaging problems and serious injury during MRI. We report a case of auriculotherapy magnets which escaped detection despite the use of screening forms and a walk‐through metal detector. The magnets caused image artifact but no other patient harm. We recommend updating patient screening practices and educating providers placing therapeutic magnets and performing MRIs of this new potential MRI hazard. J. Magn. Reson. Imaging 2015;41:858–860. © 2014 Wiley Periodicals, Inc.
Finite element method investigation of electrostatic precipitator performance
Authors: Hamou Nouri , Massinissa Aissou , Hakim Aitsaid , Youcef Zebboudj
Published: April 2014

This paper aims at analysis of the monopolar ionized field in electrostatic precipitator. A numerical model for simulating precipitation of particles in electrostatic precipitator is discussed in this paper. It includes all essential phenomena affecting the process.

An iterative finite‐element technique is used to solve Poison's equation. We proposed the introduction of a potential corresponding to the critical minimum ionization field directly in the finite element formulation as a Dirichlet condition. The theoretical migration velocity is obtained by balancing the drag force with the Coulomb force or electrostatic force acting on a particle. We used the model introduced by Cochet for predicting a particle charge. The model assumes that a particle of the same size attains an equivalent maximum amount of charge for a charging time equal to infinity. Particles influence the electrical field, flow field, electrical migration velocity, gas discharge, particle charge and collection efficiency. Copyright © 2014 John Wiley & Sons, Ltd.
Ochratoxin A released back into the medium by Saccharomyces cerevisiae as a function of the strain, washing medium and fermentative conditions
Authors: Bevilacqua Antonio , Petruzzi Leonardo , Corbo Maria Rosaria , Baiano Antonietta , Garofalo Carmela , Sinigaglia Milena
Published: April 2014

BACKGROUND

This study was aimed at investigating the removal of ochratoxin A (OTA) by two wild strains of Saccharomyces cerevisiae (W20 and W30) in a semi‐synthetic medium under two temperatures (25, 30 °C) and sugar levels (200, 250 g L−1), as well as the stability of OTA–yeast complex by evaluating the amount of bound toxin released back after some washing treatments with phosphate‐buffered saline (PBS) or model wine (MW). In addition, the main products of fermentation were studied.

RESULTS

Both W20 and W30 strains reduced OTA with removal percentages of 5.41–49.58%, and this process was affected by temperature and sugar concentration. Concerning the stability of the OTA–yeast complex, the amount of bound toxin decreased by 20–99% after five passes of washing, with a strong strain dependence and an effect of temperature and sugar concentration only for the W30 isolate. In addition, the two strains showed interesting technological properties in terms of fermentation products in a semi‐synthetic medium (high ethanol yield, volatile acidity as acetic acid < 1.2 g L−1; glycerol production exceeding 5.2 g L−1).

CONCLUSIONS

Apart from the removal of OTA, release of the toxin is a variable process and relies upon the strain effect; a significance of the other factors of the design (sugar concentration, temperature) was found only for a single isolate. Thus evaluation of the stability of the complex yeasts/OTA should be an additional trait to select promising functional yeasts. © 2014 Society of Chemical Industry
Structure determination of two new indole‐diterpenoids from Penicillium sp. CM‐7 by NMR spectroscopy
Authors: Zhang Yu‐Hong , Huang Sheng‐Dong , Pan Hua‐Qi , Bian Xi‐Qing , Wang Zai‐Ying , Han Ai‐Hong , Bai Jiao
Published: April 2014

Two new indole‐diterpenoids 4b‐deoxy‐1′‐O‐acetylpaxilline (1) and 4b‐deoxypenijanthine A (2) were isolated from the fermentation broth and the mycelia of the soil fungus Penicillium sp. CM‐7, along with three known structurally related compounds, 1′‐O‐acetylpaxilline (3), paspaline (4) and 3‐deoxo‐4b‐deoxypaxilline (5). The structures of compounds 1 and 2 were elucidated by extensive spectroscopic methods, especially 2D NMR, and their absolute configurations were suggested on the basis of the circular dichroism spectral analysis and the NOESY data. Copyright © 2014 John Wiley & Sons, Ltd.
Vancomycin‐Associated Nephrotoxicity in Adult Medicine Patients: Incidence, Outcomes, and Risk Factors
Authors: Meaney Calvin J. , Hynicka Lauren M. , Tsoukleris Mona G.
Published: April 2014

Objective

The prevalence of vancomycin‐associated nephrotoxicity (VAN) is reported to vary from 1.0–42.6%, with most data from critically ill patients. Evaluation of VAN among internal medicine patients is lacking. Our objectives were to determine the incidence, time‐course, outcomes, and risk factors of VAN in adult internal medicine patients.

Design

Retrospective cohort.

Setting

Tertiary care academic medical center.

Patients

A total of 125 adult internal medicine patients receiving vancomycin treatment with mean baseline creatinine clearance of 84.6 ± 27.6 ml/min.

Intervention

Vancomycin treatment for a minimum of 72 hours.

Measurements and Main Results

Nephrotoxicity, defined as an increase in serum creatinine of 0.5 mg/dl or 50% above baseline (whichever was larger), occurred in 17 (13.6%) of 125 patients. No patients with VAN progressed to Loss or End stage as defined by the RIFLE criteria. The incidence rate of VAN was 0.02 cases/day of vancomycin treatment. Nephrotoxicity developed at a median of 4.5 days (interquartile range [IQR] 2.2–4.9) peaked at 5.7 days (IQR: 3.8–9.6), and resolved in 70.6% of the cases within 16.5 days (IQR: 6.0–17.8) after onset. On multivariable logistic regression analysis, after controlling for hypotensive episodes, Charlson Comorbidity Index, and baseline creatinine clearance, concomitant use of piperacillin‐tazobactam was associated with increased VAN (adjusted odds ratio 5.36, 95% confidence interval 1.41–20.5).

Conclusions

Vancomycin‐associated nephrotoxicity is prevalent among internal medicine patients, with 5.36‐fold higher odds if piperacillin‐tazobactam is concomitantly administered.
Chain‐growth condensation polymerization approach to synthesis of well‐defined polybenzoxazole: Importance of higher reactivity of 3‐amino‐4‐hydroxybenzoic acid ester compared to 4‐amino‐3‐hydroxybenzoic acid ester
Authors: Ohta Yoshihiro , Niiyama Tetsurou , Yokoyama Akihiro , Yokozawa Tsutomu
Published: April 2014

Application of chain‐growth condensation polymerization (CGCP) to obtain well‐defined polybenzoxazole (PBO) was examined. CGCP of both phenyl 3‐{(2‐methoxyethoxy)methoxy (MEM‐oxy)}‐4‐(octylamino)benzoate (1b) (para‐substituted monomer) and phenyl 4‐MEM‐oxy‐3‐(octylamino)benzoate (3b) (meta‐substituted monomer) was examined in the presence of metal disilazide base and phenyl 4‐nitro‐ or methylbenzoate 2 as an initiator. Polymerization of the latter monomer, but not the former, afforded polymer with controlled molecular weight based on the feed ratio of monomer to initiator and with a narrow molecular weight distribution. Accordingly, monomer 3c, in which the octyl group on the amino nitrogen of 3b was replaced with a 4‐(octyloxy)benzyl (OOB) group, was polymerized in the presence of lithium 1,1,1,3,3,3‐hexamethyldisilazide (LiHMDS), phenyl 4‐methylbenzoate (2b), and LiCl in THF at 0 °C to yield poly3c with well‐defined molecular weight (Mn = 4520–9080) and low polydispersity (Mw/Mn ≤ 1.11). Treatment of poly3c with trifluoroacetic acid simultaneously removed the MEM and OOB groups, affording poly(o‐hydroxyamide) (poly4) without scission of the amide linkages. Cyclodehydration of poly4 proceeded at 350 °C to yield PBO (poly5), which was insoluble in organic solvents and acids. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1730–1736
Resistance to acetyl‐CoA carboxylase‐inhibiting herbicides
Authors: Kaundun Shiv S
Published: April 2014

Resistance to acetyl‐CoA carboxylase herbicides is documented in at least 43 grass weeds and is particularly problematic in Lolium, Alopecurus and Avena species. Genetic studies have shown that resistance generally evolves independently and can be conferred by target‐site mutations at ACCase codon positions 1781, 1999, 2027, 2041, 2078, 2088 and 2096. The level of resistance depends on the herbicides, recommended field rates, weed species, plant growth stages, specific amino acid changes and the number of gene copies and mutant ACCase alleles. Non‐target‐site resistance, or in essence metabolic resistance, is prevalent, multigenic and favoured under low‐dose selection. Metabolic resistance can be specific but also broad, affecting other modes of action. Some target‐site and metabolic‐resistant biotypes are characterised by a fitness penalty. However, the significance for resistance regression in the absence of ACCase herbicides is yet to be determined over a practical timeframe. More recently, a fitness benefit has been reported in some populations containing the I1781L mutation in terms of vegetative and reproductive outputs and delayed germination. Several DNA‐based methods have been developed to detect known ACCase resistance mutations, unlike metabolic resistance, as the genes remain elusive to date. Therefore, confirmation of resistance is still carried out via whole‐plant herbicide bioassays. A growing number of monocotyledonous crops have been engineered to resist ACCase herbicides, thus increasing the options for grass weed control. While the science of ACCase herbicide resistance has progressed significantly over the past 10 years, several avenues provided in the present review remain to be explored for a better understanding of resistance to this important mode of action. © 2014 Society of Chemical Industry
A Self‐learning Framework for Statistical Ground Classification using Radar and Monocular Vision
Authors: Milella Annalisa , Reina Giulio , Underwood James
Published: April 2014

Reliable terrain analysis is a key requirement for a mobile robot to operate safely in challenging environments, such as in natural outdoor settings. In these contexts, conventional navigation systems that assume a priori knowledge of the terrain geometric properties, appearance properties, or both, would most likely fail, due to the high variability of the terrain characteristics and environmental conditions. In this paper, a self‐learning framework for ground detection and classification is introduced, where the terrain model is automatically initialized at the beginning of the vehicle's operation and progressively updated online. The proposed approach is of general applicability for a robot's perception purposes, and it can be implemented using a single sensor or combining different sensor modalities. In the context of this paper, two ground classification modules are presented: one based on radar data, and one based on monocular vision and supervised by the radar classifier. Both of them rely on online learning strategies to build a statistical feature‐based model of the ground, and both implement a Mahalanobis distance classification approach for ground segmentation in their respective fields of view. In detail, the radar classifier analyzes radar observations to obtain an estimate of the ground surface location based on a set of radar features. The output of the radar classifier serves as well to provide training labels to the visual classification module. Once trained, the vision‐based classifier is able to discriminate between ground and nonground regions in the entire field of view of the camera. It can also detect multiple terrain components within the broad ground class. Experimental results, obtained with an unmanned ground vehicle operating in a rural environment, are presented to validate the system. It is shown that the proposed approach is effective in detecting drivable surface, reaching an average classification accuracy of about 80% on the entire video frame with the additional advantage of not requiring human intervention for training or a priori assumption on the ground appearance.
A Comparison of Automatic Nap‐of‐the‐earth Guidance Strategies for Helicopters
Authors: Johnson Eric N. , Mooney John G.
Published: April 2014

This paper describes updated results from a partnership between the Sikorsky Aircraft Corporation and the Georgia Institute of Technology to develop, improve, and flight‐test a sensor, guidance, navigation, control, and real‐time flight path optimization system to support high‐performance nap‐of‐the‐earth helicopter flight. Multiple obstacle avoidance methods are evaluated, including (1) a simple processing of each laser scan; (2) a motion primitive optimization method, and (3) a potential‐field‐based method. Simulation and flight test results have been obtained utilizing an onboard laser scanner to detect terrain and obstacles while flying at low altitude, and they have successfully demonstrated obstacle avoidance in a realistic semiurban environment at speeds up to 12 m/s while maintaining a specified vertical and horizontal miss distance. Additionally, the performance of the selected LIDAR model in multiple degraded environments was observed. The performances of the three guidance methods are directly compared, using a published benchmark performance for reference. These results validate the above approaches and pave the way for extensions to this work, including investigation of additional motion primitives and the relationship between sensor range and aircraft performance requirements.
On longest paths and diameter in random apollonian networks
Authors: Ebrahimzadeh Ehsan , Farczadi Linda , Gao Pu , Mehrabian Abbas , Sato Cristiane M. , Wormald Nick , Zung Jonathan
Published: April 2014

We consider the following iterative construction of a random planar triangulation. Start with a triangle embedded in the plane. In each step, choose a bounded face uniformly at random, add a vertex inside that face and join it to the vertices of the face. After n – 3 steps, we obtain a random triangulated plane graph with n vertices, which is called a Random Apollonian Network (RAN). We show that asymptotically almost surely (a.a.s.) a longest path in a RAN has length o(n), refuting a conjecture of Frieze and Tsourakakis. We also show that a RAN always has a cycle (and thus a path) of length , and that the expected length of its longest cycles (and paths) is . Finally, we prove that a.a.s. the diameter of a RAN is asymptotic to , where is the solution of an explicit equation. © 2014 Wiley Periodicals, Inc. Random Struct. Alg., 45, 703–725, 2014
Zur Nachhaltigkeit von Stahl‐ und Verbund‐ konstruktionen bei Büro‐ und Verwaltungsgebäuden – Teil 1: Tragkonstruktionen
Authors: Stroetmann Richard , Podgorski Christine
Published: April 2014

Im folgenden Beitrag wird auf die Nachhaltigkeit von Tragkonstruktionen für Büro‐ und Verwaltungsgebäude eingegangen. Nach einer Beschreibung der Anforderungen aus der Objekt‐ und Tragwerksplanung werden Deckensysteme in Verbundbauweise, die Systemwahl und seine statisch‐konstruktive Auslegung erläutert. Zur Nachhaltigkeit wird zunächst eine Übersicht über Prinzipien, die Normungssituation und die Umsetzung im AIF‐FOSTA‐Projekt P881 [1] gegeben. Anschließend werden Grundlagen und Wege zur Beurteilung der ökologischen und ökonomischen Qualitäten beschrieben. Es folgen Parameterstudien zur Optimierung und Einordnung der Tragkonstruktionen nach Nachhaltigkeitskriterien. Zur Begrenzung des Umfangs werden zunächst Untersuchungen zu Deckensystemen vorgestellt. Ein noch folgender Beitrag enthält weitere Parameterstudien unter Einbeziehung von Gebäudestützen und Brandschutzmaßnahmen.

Sustainability of steel and composite structures of office and administration buildings – Part 1: structural systems. The following article concerns the sustainability of structural systems of office and administration buildings. After a description of the requirements resulting from the building and structural design, slab systems in composite construction, the choice of the structural system as well as structural design will be explained. With respect to the sustainability an overview of the principles, the standardization situation and the implementation into the AIF‐FOSTA‐project P881 [1] is given. Subsequently basics and methods to assess the environmental and economic performances are described. Parameter studies for optimization and classification of the structural system according to sustainability criteria are following. To limit the scope, firstly, investigations of slab systems are presented. A following article will include further parameter studies involving columns and fire protection measures.
Versuche zur Zug‐Abscher‐Interaktionstragwirkung von Schrauben
Authors: Renner Anja , Lange Jörg
Published: April 2014

Seit Mitte des vergangenen Jahrhunderts sind Schrauben im Stahlbau als Verbindungsmittel etabliert. Für viele Anwender kam daher die Änderung der Interaktionsformel zur Bemessung von Schrauben unter kombinierter Zug‐Abscher‐Beanspruchung im neu eingeführten Eurocode 3 (DIN EN 1993‐1‐8) gegenüber der altbekannten DIN 18800‐Formel sehr überraschend. Die bisher vertraute quadratische Interaktion wird im Eurocode durch eine deutlich konservativere, bi‐lineare Funktion ersetzt. Auf der Suche nach einer Antwort auf die Frage, welche Funktion zur Beschreibung des Tragverhaltens von Schrauben unter kombinierter Belastung richtig ist, wurde am Fachgebiet Stahlbau der TU Darmstadt eine Reihe von Versuchen durchgeführt.

Experimental study on the combined tension and shear load bearing behavior of bolts. Since the middle of last century bolts are an established part of connections in steel structures. Therefore for many design engineers the change in the design rule for bolts under combined tension and shear load in the newly introduced Eurocode 3 (EN 1993‐1‐8) towards the well‐known DIN 18800 design rule came rather as a surprise. The hitherto quadratic interaction function is replaced by a by far more conservative, bi‐linear function. Searching for the answer to the question, which function really describes the behavior of bolts under combined load, a number of tests were conducted at the Department of Steel Structures at the TU Darmstadt.
Stability of steel structures in fire
Authors: Knobloch Markus
Published: April 2014

The stability behaviour of steel structures in fire is strongly affected by the decreasing stiffness during heating, the nonlinear elevated temperature stress‐strain response and thermal creep effects. The paper gives an overview of studies on the fire behaviour of steel structures. A major focus of the paper is to summarize recent studies on the material, cross‐sectional, member and global structure level performed in Switzerland in recent years. The results of the studies indicate that the use of force‐based analytical models using uniform temperature‐dependent effective yield strengths, as used for ambient temperature designs, are less suitable for fire design and distinct nonlinear material behaviour then deformation‐based models which have been proposed for different stability phenomena. These models seem to accurately predict the fire behaviour of steel structures on all structural levels.

Stabilitätsverhalten von Stahltragwerken im Brandfall – Stand der Forschung, aktuelle Studien in der Schweiz und zukünftige Entwicklungen. Das Stabilitätsverhalten von Stahltragwerken im Brandfall wird entscheidend von der abnehmenden Steifigkeit während der Erwärmung, dem nichtlinearen Spannungs‐Dehnungsverhalten von Baustahl bei erhöhten Temperaturen sowie den Hochtemperaturkriecheffekten beeinflusst. Die Veröffentlichung gibt einen Überblick über Untersuchungen zum Brandverhalten von Stahlkonstruktionen und fasst dabei insbesondere die Ergebnisse neuerer in der Schweiz durchgeführter Studien auf Material‐, Querschnitts‐, Bauteil‐ und Tragwerksebene zusammen. Die Ergebnisse zeigen, dass verformungsgrößenorientierte analytische Modelle das Brandverhalten von Stahlkonstruktionen zutreffend beschreiben können und für ausgeprägt nichtlineares Materialverhalten besser geeignet sind als konventionelle schnittgrößenorientierte Tragmodelle.
Zur Stabilität von oberflächennah durch plastisches Umformen eingeprägten Eigenspannungen
Authors: Mangerig Ingbert , Hess Andreas
Published: April 2014

Durch das Einprägen von oberflächennahen Eigenspannungen kann die Lebensdauer von Metallbauteilen erheblich erhöht werden. An den Außenflächen werden dabei durch plastisches Umformen Druckeigenspannungen erzeugt, die zusammen mit Zugeigenspannungen ein Gleichgewichtssystem bilden. Da bei schwingenden Beanspruchungen mit anwachsenden Schädigungen auch zunehmende Verzerrungen entstehen, die Aufrechterhaltung von Eigenspannungen aber eine Blockade von Bewegungen voraussetzt, sind im Zusammenhang mit deren Stabilität Fragen der Materialdegradation zu behandeln. Ausgehend von Versetzungsbewegungen werden Fragen zur Stabilität eingeprägter plastischer Verformungen diskutiert und Befunde von Ermüdungstests an nachbehandelten Schweißnähten vorgestellt.

The stability of subsurface residual stresses induced by plastic deformation. Induced subsurface residual compression stresses can considerably increase the service life of metal components. In the case of such stresses on the outer surfaces generated by plastic deformation an equilibrium system with residual tensile stresses inside exists. Under cyclic loading the material degradation process causes with increased strains against the odds of a continued existence of residual stresses. In accordance with material degradation questions with regard to the stability of imposed residual stresses have to be answered. The dislocation motion issues are discussed in view of the stability induced plastic deformations, moreover, results of fatigue tests on specimen with post‐treated welds are presented.
Genistein increases glycosaminoglycan levels in mucopolysaccharidosis type I cell models
Authors: Kingma Sandra D. K. , Wagemans Tom , IJlst Lodewijk , Wijburg Frits A. , van Vlies Naomi
Published: April 2014

Mucopolysaccharidosis type I (MPS I) is a lysosomal storage disorder characterized by diminished degradation of the glycosaminoglycans (GAGs) heparan sulfate and dermatan sulfate, which results in the accumulation of these GAGs and subsequent cellular dysfunction. Patients present with a variety of symptoms, including severe skeletal disease. Genistein has been shown previously to inhibit GAG synthesis in MPS fibroblasts, presumably through inhibition of tyrosine kinase activity of the epidermal growth factor receptor (EGFR). To determine the potentials of genistein for the treatment of skeletal disease, MPS I fibroblasts were induced into chondrocytes and osteoblasts and treated with genistein. Surprisingly, whereas tyrosine phosphorylation levels (as a measure for tyrosine kinase inhibition) were decreased in all treated cell lines, there was a 1.3 and 1.6 fold increase in GAG levels in MPS I chondrocytes and fibroblast, respectively (p < 0.05). Sulfate incorporation in treated MPS I fibroblasts was 2.6 fold increased (p < 0.05), indicating increased GAG synthesis despite tyrosine kinase inhibition. This suggests that GAG synthesis is not exclusively regulated through the tyrosine kinase activity of the EGFR. We hypothesize that the differences in outcomes between studies on the effect of genistein in MPS are caused by the different effects of genistein on different growth factor signaling pathways, which regulate GAG synthesis. More studies are needed to elucidate the precise signaling pathways which are affected by genistein and alter GAG metabolism in order to evaluate the therapeutic potential of genistein for MPS patients.
Narratives and traits in personality development among New Zealand Māori, Chinese, and European adolescents
Authors: Reese Elaine , Chen Yan , McAnally Helena M. , Myftari Ella , Neha Tia , Wang Qi , Jack Fiona
Published: April 2014

Narrative and trait levels of personality were assessed in a sample of 268 adolescents from age 12 to 21 from New Zealand Māori, Chinese, and European cultures. Adolescents narrated three critical events and completed a Big Five personality inventory. Each narrative was coded for causal and thematic coherence. NZ Chinese adolescents reported lower levels of extraversion, agreeableness, conscientiousness, and openness, and higher levels of neuroticism, than NZ Māori or European adolescents. Cultural differences were also evident in narrative coherence. Adolescents in all three groups demonstrated age‐related increases in thematic coherence, but only NZ European adolescents demonstrated the expected age‐related increases in causal coherence. Narrative identity and traits were distinct aspects of personality for younger adolescents, but were linked for middle and older adolescents. These findings support the importance of both narrative identity and traits in understanding personality development in adolescents across cultures.
Identity formation of Italian emerging adults living with parents: A narrative study
Authors: Aleni Sestito Laura , Sica Luigia S.
Published: April 2014

This study examines the links between family and identity processes of Italian emerging adults living with their parents. Examining the impact of family is important in the countries of Mediterranean area where also emerging adults live with parents for a prolonged time. In Italy living with parents is associated with a specific “delay syndrome” in the transition to adulthood. Participants consisted of 20 Italian emerging adults attending second and last years of university, in a large Italian city (Naples). All participants were subjected to an open interview, based on the thematic life story. Our findings indicate that parents are perceived as active agents of identity, responsive and supportive of autonomy; they encourage the active involvement of young people in the work of identity formation. Despite this, parental impact produces different configurations that could shed light on the pathways of Italian emerging adults' transition to adulthood. The above configurations are discussed using exemplars.
Homeschooled adolescents in the United States: Developmental outcomes
Authors: Green‐Hennessy Sharon
Published: April 2014

The mission of schools has broadened beyond academics to address risk behaviors such as substance use, delinquency, and socialization problems. With an estimated 3.4% of all U.S. youth being homeschooled, this study examines how U.S. homeschoolers fare on these outcomes given their lack of access to these school services. Adolescents (ages 12–17) from the 2002 through 2011 National Surveys of Drug Use and Health (NSDUH) were divided based on school status (home vs. traditional schooling) and religious affiliation (stronger vs. weaker). Controlling for demographic differences, homeschoolers with weaker religious ties were three times more likely to report being behind their expected grade level and two and a half times more likely to report no extracurricular activities in the prior year than their traditionally schooled counterparts. This group was also more likely to report lax parental attitudes toward substance use. Findings suggest homeschoolers with weaker religious ties represent an at‐risk group.
Characterization of residue‐dependent differences in the peripheral membrane association of the FATC domain of the kinase ‘target of rapamycin’ by NMR and CD spectroscopy
Authors: Sommer Lisa A.M. , Dames Sonja A.
Published: April 2014

The conserved C‐terminal FATC domain of the kinase ‘target of rapamycin’ is important for its regulation and was suggested to contain a peripheral membrane anchor. Here, we present the characterization of the interactions of the yeast TOR1 FATC domain (2438–2470 = y1fatc) and 15 mutants with membrane mimetic micelles, bicelles, and small unilamellar vesicles (SUVs) by NMR and CD spectroscopy. Replacement of up to 6–7 residues did not result in a significant abrogation of the association with micelles or bicelles. However, replacement of only one residue could result in an impairment of the interaction with SUVs that are usually used at low concentrations. Some mutants not binding liposomes may be introduced in full‐length TOR for future functional and localization studies in vivo.
Obstetric competence among referral healthcare providers in Mali
Authors: Huchon Cyrille , Arsenault Catherine , Tourigny Caroline , Coulibaly Aliou , Traore Mamadou , Dumont Alexandre , Fournier Pierre
Published: April 2014

Objective

To determine the factors associated with obstetric competency and clinical practice among obstetric care providers in referral health centers in Mali.

Methods

The present cross‐sectional study was conducted between March and May 2012 among 140 obstetric care providers (obstetric nurses, midwives, and physicians) working in referral health centers in Mali. Emergency obstetric care knowledge and skills were evaluated with clinical vignettes developed using national Malian guidelines. The vignettes covered 5 areas of emergency obstetric care, and the results were used to generate a competency score. A backward stepwise random‐effects model using a maximum likelihood estimator was applied to evaluate variables independently associated with competency score.

Results

Out of 100, the mean ± SD score was 57.8 ± 11.2 for obstetric nurses, 66.4 ± 14.7 for midwifes, and 78.6 ± 13.4 for physicians (P < 0.001). Three variables were significantly associated with a higher competency score: professional qualification, working in an urban setting, and working in a health center with a smaller number of obstetric care providers.

Conclusion

Increasing the in‐service training of both rural staff and lower‐level healthcare workers working in larger health centers via facility‐based maternal death reviews might help to improve clinical practice and maternal health outcomes.