bluuebunny/crossref_metadata_2025 huggingface dataset:
PSYCHOMETRICS OF THE PRESCHOOL BEHAVIORAL AND EMOTIONAL RATING SCALE WITH CHILDREN FROM EARLY CHILDHOOD SPECIAL EDUCATION SETTINGS
Authors: Lambert Matthew C. , Cress Cynthia J. , Epstein Michael H.
Published: April 2015

In a previous study with a nationally representative sample, researchers found that the items of the Preschool Behavioral and Emotional Rating Scale can best be described by a four‐factor structure model (Emotional Regulation, School Readiness, Social Confidence, and Family Involvement). The findings of this investigation replicate and extend these previous results with a national sample of children (N = 1,075) with disabilities enrolled in early childhood special education programs. Data were analyzed using classical tests theory, Rasch modeling, and confirmatory factor analysis. Results confirmed that for the most part, individual items were internally consistent within a four‐factor model and showed consistent item difficulty, discrimination, and fit relative to their respective subscale scores.
Uric Acid Promotes Osteogenic Differentiation and Inhibits Adipogenic Differentiation of Human Bone Mesenchymal Stem Cells
Authors: Li Hui‐Zhang , Chen Zhi , Hou Cang‐Long , Tang Yi‐Xing , Wang Fei , Fu Qing‐Ge
Published: April 2015

To investigate the effect of uric acid on the osteogenic and adipogenic differentiation of human bone mesenchymal stem cells (hBMSCs). The hBMSCs were isolated from bone marrow of six healthy donors. Cell morphology was observed by microscopy and cell surface markers (CD44 and CD34) of hBMSCs were analyzed by immunofluorescence. Cell morphology and immunofluorescence analysis showed that hBMSCs were successfully isolated from bone marrow. The number of hBMSCs in uric acid groups was higher than that in the control group on day 3, 4, and 5. Alizarin red staining showed that number of calcium nodules in uric acid groups was more than that of the control group. Oil red‐O staining showed that the number of red fat vacuoles decreased with the increased concentration of uric acid. In summary, uric acid could promote the proliferation and osteogenic differentiation of hBMSCs while inhibit adipogenic differentiation of hBMSCs.
Undifferentiated Neuroblastoma Cells Are More Sensitive to Photogenerated Oxidative Stress Than Differentiated Cells
Authors: Lee Chu‐I , Perng Jing‐Huei , Chen Huang‐Yo , Hong Yi‐Ren , Wang Jyh‐Jye
Published: April 2015

Neuroblastoma is one of the most aggressive cancers and has a complex form of differentiation. We hypothesized that advanced cellular differentiation may alter the susceptibility of neuroblastoma to photodynamic treatment (PDT) and confer selective survival advantage. We demonstrated that hematoporphyrin uptake by undifferentiated SH‐SY5Y cells was lower than that of differentiated counterparts, yet the former were more susceptible to PDT‐induced oxidative stress killing. Photogenerated reactive oxygen species (ROS) in undifferentiated cells efficiently stimulated cell cycle arrest at G2/M phase, mitochondrial apoptotic pathway activation, the sustained phosphorylation of Akt/GSK‐3β and ERK. Differentiated cells with more resistance to PDT exhibited a ROS‐independent and a prolonged activation of ERK. Both SH‐SY5Y cells exposed to PDT exhibited ROS‐independent p38 and JNK activation. These results may have important implications for neuroblastoma patients undergoing photodynamic therapy. J. Cell. Biochem. 116: 2074–2085, 2015. © 2015 Wiley Periodicals, Inc.
Sarcopenia, obesity and sarcopenic obesity: effects on liver function and volume in patients scheduled for major liver resection
Authors: Lodewick Toine M. , Roeth Anjali A.J. , Olde Damink Steven W.M. , Alizai Patrick H. , van Dam Ronald M. , Gassler Nikolaus , Schneider Mark , Dello Simon A.W.G. , Schmeding Maximilian , Dejong Cornelis H.C. , Neumann Ulf P.
Published: April 2015

Background

Sarcopenia, obesity and sarcopenic obesity have been linked to impaired outcome after liver surgery. Preoperative liver function of sarcopenic, obese and sarcopenic‐obese patients might be reduced, possibly leading to more post‐operative morbidity. The aim of this study was to explore whether liver function and volume were influenced by body composition in patients undergoing liver resection.

Methods

In 2011 and 2012, all consecutive patients undergoing the methacetin breath liver function test were included. Liver volumetry and muscle mass analysis were performed using preoperative CT scans and Osirix® software. Muscle mass and body‐fat% were calculated. Predefined cut‐off values for sarcopenia and the top two body‐fat% quintiles were used to identify sarcopenia and obesity, respectively. Histologic assessment of the resected liver gave insight in background liver disease.

Results

A total number of 80 patients were included. Liver function and volume were comparable in sarcopenic(‐obese) and non‐sarcopenic(‐obese) patients. Obese patients showed significantly reduced liver function [295 (95–508) vs. 358 (96–684) µg/kg/h, P = 0.018] and a trend towards larger liver size [1694 (1116–2685) vs. 1533 (869–2852) mL, P = 0.079] compared with non‐obese patients. Weight (r = −0.40), body surface area (r = −0.32), estimated body‐fat% (r = −0.43) and body mass index (r = −0.47) showed a weak but significant negative (all P < 0.05) correlation with liver function. Moreover, body‐fat% was identified as an independent factor negatively affecting the liver function.

Conclusion

Sarcopenia and sarcopenic obesity did not seem to influence liver size and function negatively. However, obese patients had larger, although less functional, livers, indicating dissociation of liver function and volume in these patients.
Coloring Triple Systems with Local Conditions
Authors: Mubayi Dhruv
Published: April 2015

We produce an edge‐coloring of the complete 3‐uniform hypergraph on n vertices with colors such that the edges spanned by every set of five vertices receive at least three distinct colors. This answers the first open case of a question of Conlon‐Fox‐Lee‐Sudakov (Int Math Res Not, to appear)  who asked whether such a coloring exists with colors.
Stereoselective Synthesis of cis,cis‐Configured Perhydroquinoxaline‐5‐Carbonitrile from Cyclohex‐2‐en‐1‐ol
Authors: Schulte Adrian , Saito Susumu , Wünsch Bernhard
Published: April 2015

cis,cis‐Configured perhydroquinoxaline‐5‐carbonitrile 10 was synthesized stereoselectively by ditosylation of trans,cis‐2,3‐dihydroxycyclohexane‐1‐carbonitrile 4 and subsequent reaction with ethylenediamine. The diol precursor 4 was stereoselectively obtained by regioselective opening of the epoxide 3 with KCN in water avoiding hazardous Et2AlCN.
Early and resectable HCC: Definition and validation of a subgroup of patients who could avoid liver transplantation
Authors: Scatton Olivier , Goumard Claire , Cauchy Francois , Fartoux Laetitia , Perdigao Fabiano , Conti Filomena , Calmus Yvon , Boelle Pierre Yves , Belghiti Jacques , Rosmorduc Olivier , Soubrane Olivier
Published: April 2015

Background

Liver transplantation (LT) remains the best curative option for early hepatocellular carcinoma (HCC) but is limited by the ongoing graft shortage. The present study aimed at defining the population in which primary liver resection (LR) could represent the best alternative to LT.

Methods

An exploration set of 357 HCC patients (LR n = 221 and LT n = 136) operated between 2000–2012 was used in order to identify factors associated with survival following LR and define a good prognosis (GP) group for which LR may challenge the results of upfront LT. These factors were validated in an external validation set of 565 HCC patients operated at another center (LR n = 287 LR and LT n = 278).

Results

In the exploration set, factors associated with survival on multivariate analysis were a solitary lesion, a diameter <50 mm, a well‐moderately differentiated lesion, the absence of microvascular invasion, and preoperative AST level <2N. Thirty‐nine patients (18%) displayed all these criteria and constituted the GP patients. Overall survivals at 1, 3, and 5 years did not significantly differ between GP resected patients, and the in Milan transplanted patients (93, 80.4, and 80.4% vs. 86.9, 82, and 78.8%, P = 0.79). In the validation cohort, patients with GP factors of survival still displayed better overall survivals than those without (P = 0.036) but also displayed better survivals than in Milan HCC transplanted patients (P = 0.005).

Conclusion

In a group of early HCC patients gathering all factors of GP, primary LR achieves at least similar survival as upfront LT and should be the approach of choice. J. Surg. Oncol. 2015 111:1007–1015. © 2015 Wiley Periodicals, Inc.
Uncovering dental implants using a new thermo‐optically powered (TOP) technology with tissue air‐cooling
Authors: Romanos Georgios E. , Belikov Andrey V. , Skrypnik Alexei V. , Feldchtein Felix I. , Smirnov Michael Z. , Altshuler Gregory B.
Published: April 2015

Background and Objectives

Uncovering implants with lasers, while bloodless, has been associated with a risk of implant and bone overheating. The present study evaluated the effect of using a new generation of high‐power diode lasers on the temperature of a dental implant and the surrounding tissues using an in vitro model.

Study Design/Materials and Methods

The implant temperature was measured at three locations using micro thermocouples. Collateral thermal damage of uncovered soft tissues was evaluated using NTBC stain. Implant temperature rise during and collateral thermal soft‐tissue damage following implant uncovering with and without tissue air‐cooling was studied using both the classic operational mode and the new thermo‐optically powered (TOP) technology.

Results

For the classic surgical mode using a cork‐initiated tip and constant laser power set at 3.4 W, the maximum temperature rise in the coronal and apical parts of the implant was 23.2 ± 4.1°С and 9.5 ± 1.8°С, respectively, while 1.5 ± 0.5 mm of collateral thermal damage of the soft tissue surrounding the implant model occurred. Using the TOP surgical tip with constant laser power reduced implant overheating by 30%; collateral thermal soft‐tissue damage was 0.8 ± 0.2 mm. Using the TOP surgical mode with a tip temperature setting of 800°C and air‐cooling reduced the implant temperature rise by more than 300%, and only 0.2 ± 0.1 mm of collateral thermal soft‐tissue damage occurred, typical for optimized CO2 laser surgery. Furthermore, use of the new generation diode technology (TOP surgical mode) appeared to reduce the time required for implant uncovering by a factor of two, compared to the standard surgical mode.

Conclusions

Use of the new generation diode technology (TOP surgical mode) may significantly reduce overheating of dental implants during uncovering and seems to be safer for the adjacent soft and hard tissues. Use of such diode lasers with air‐cooling can radically reduce the rise in implant temperatures (by more than three times), potentially making this technology safe and effective for implant uncovering. Lasers Surg. Med. 47:411–420, 2015. © 2015 Wiley Periodicals, Inc.
Template‐Assisted Preparation of Permeable Nanocapsules from Complementary Cyclodextrin and Adamantane–Appended Biocompatible Dextran Polymers
Authors: Wajs Ewelina , Nielsen Thorbjørn Terndrup , Larsen Kim Lambertsen , Fragoso Alex
Published: April 2015

Supramolecular host‐guest interactions are an attractive driving force for the preparation of two‐ and three‐dimensional materials. In this work, the fabrication of nano‐sized capsules self‐assembled by supramolecular interactions between specially designed complementary polymers using a sacrificial solid template is demonstrated. The alternate deposition of cyclodextrin and adamantane appended dextran polymers on gold nanoparticles followed by oxidative core dissolution yields well‐ordered, stable and size‐controlled nano‐architectures, which are able to encapsulate small molecules with a good stability. This technology opens the way for using guest molecules with specific functions to build more sophisticated structures that react, for example, to light or electrochemical stimuli.
Surface tensor estimation from linear sections
Authors: Kousholt Astrid , Kiderlen Markus , Hug Daniel
Published: April 2015

From Crofton's formula for Minkowski tensors we derive stereological estimators of translation invariant surface tensors of convex bodies in the n‐dimensional Euclidean space. The estimators are based on one‐dimensional linear sections. In a design based setting we suggest three types of estimators. These are based on isotropic uniform random lines, vertical sections, and non‐isotropic random lines, respectively. Further, we derive estimators of the specific surface tensors associated with a stationary process of convex particles in the model based setting.
On the American option‐pricing model with an uncertain volatility
Authors: Yin Hong‐Ming , Wang Wen
Published: April 2015

In this paper, we study an American option‐pricing model with an uncertain volatility. Some properties for the option price are derived. Particularly, a global spread for the option price is proved when the volatility depends on the underlying security and time. This result confirms the observed fact from the real financial data in option markets. Copyright © 2015 John Wiley & Sons, Ltd.
Three‐dimensional quantitative T1 and T2 mapping of the carotid artery: Sequence design and in vivo feasibility
Authors: Coolen Bram F. , Poot Dirk H.J. , Liem Madieke I. , Smits Loek P. , Gao Shan , Kotek Gyula , Klein Stefan , Nederveen Aart J.
Published: April 2015

Purpose

A novel three‐dimensional (3D) T1 and T2 mapping protocol for the carotid artery is presented.

Methods

A 3D black‐blood imaging sequence was adapted allowing carotid T1 and T2 mapping using multiple flip angles and echo time (TE) preparation times. B1 mapping was performed to correct for spatially varying deviations from the nominal flip angle. The protocol was optimized using simulations and phantom experiments. In vivo scans were performed on six healthy volunteers in two sessions, and in a patient with advanced atherosclerosis. Compensation for patient motion was achieved by 3D registration of the inter/intrasession scans. Subsequently, T1 and T2 maps were obtained by maximum likelihood estimation.

Results

Simulations and phantom experiments showed that the bias in T1 and T2 estimation was < 10% within the range of physiological values. In vivo T1 and T2 values for carotid vessel wall were 844 ± 96 and 39 ± 5 ms, with good repeatability across scans. Patient data revealed altered T1 and T2 values in regions of atherosclerotic plaque.

Conclusion

The 3D T1 and T2 mapping of the carotid artery is feasible using variable flip angle and variable TE preparation acquisitions. We foresee application of this technique for plaque characterization and monitoring plaque progression in atherosclerotic patients. Magn Reson Med 75:1008–1017, 2016. © 2015 Wiley Periodicals, Inc.
Motion robust GRAPPA for echo‐planar imaging
Authors: Baron Corey A. , Beaulieu Christian
Published: April 2015

Purpose

A readout‐segmented method for acquiring robust GRAPPA calibration data for echo‐planar imaging (EPI) was proposed and compared with two previous methods, including the gold standard interleaved approach and a single shot method with halved phase encode resolution.

Theory and Methods

The readout‐segmented and single shot techniques acquire adjacent phase encode lines in the same shot to obtain the calibration data, rather than interleaving of lines between shots, to decrease sensitivity to motion. Additionally, it uses multiple segments with shortened frequency encode extent to match the phase encode bandwidth to the undersampled data, which decreases sensitivity to B0 inhomogeneity. The three methods were tested using simulations and EPI scans of the brain in healthy volunteers.

Results

The interleaved approach exhibited high sensitivity to motion, while residual undersampling artifacts remained in the single shot method due to mismatch of B0 inhomogeneity between the calibration and undersampled data. The readout segmented method exhibited no such errors, having 30% lower ghosting intensity than the single shot method and 90% lower ghosting intensity than the interleaved approach in moving subjects.

Conclusion

Artifacts from B0 inhomogeneity and motion during calibration scans for EPI GRAPPA can be mitigated with a readout segmented calibration scan. Magn Reson Med 75:1166–1174, 2016. © 2015 Wiley Periodicals, Inc.
Assessment of blood flow velocity and pulsatility in cerebral perforating arteries with 7‐T quantitative flow MRI
Authors: Bouvy W. H. , Geurts L. J. , Kuijf H. J. , Luijten P. R. , Kappelle L. J. , Biessels G. J. , Zwanenburg J. J. M.
Published: April 2015

Thus far, blood flow velocity measurements with MRI have only been feasible in large cerebral blood vessels. High‐field‐strength MRI may now permit velocity measurements in much smaller arteries. The aim of this proof of principle study was to measure the blood flow velocity and pulsatility of cerebral perforating arteries with 7‐T MRI. A two‐dimensional (2D), single‐slice quantitative flow (Qflow) sequence was used to measure blood flow velocities during the cardiac cycle in perforating arteries in the basal ganglia (BG) and semioval centre (CSO), from which a mean normalised pulsatility index (PI) per region was calculated (n = 6 human subjects, aged 23–29 years). The precision of the measurements was determined by repeated imaging and performance of a Bland–Altman analysis, and confounding effects of partial volume and noise on the measurements were simulated. The median number of arteries included was 14 in CSO and 19 in BG. In CSO, the average velocity per volunteer was in the range 0.5–1.0 cm/s and PI was 0.24–0.39. In BG, the average velocity was in the range 3.9–5.1 cm/s and PI was 0.51–0.62. Between repeated scans, the precision of the average, maximum and minimum velocity per vessel decreased with the size of the arteries, and was relatively low in CSO and BG compared with the M1 segment of the middle cerebral artery. The precision of PI per region was comparable with that of M1. The simulations proved that velocities can be measured in vessels with a diameter of more than 80 µm, but are underestimated as a result of partial volume effects, whilst pulsatility is overestimated. Blood flow velocity and pulsatility in cerebral perforating arteries have been measured directly in vivo for the first time, with moderate to good precision. This may be an interesting metric for the study of haemodynamic changes in aging and cerebral small vessel disease. © 2015 The Authors NMR in Biomedicine Published by John Wiley & Sons Ltd.
Uzawa algorithms with variable relaxation for nonsymmetric generalized saddle point problems
Authors: Shen Hailun , Xiang Hua
Published: April 2015

In this paper, we extend the inexact Uzawa algorithm of Hu and Zou to the nonsymmetric generalized saddle point problem (SPP). The techniques used here are similar with those in the paper of Bramble et al., where the convergence of Uzawa type algorithm for solving nonsymmetric case depends on the spectrum of the preconditioners involved. The main contributions of this paper focus on two new linear Uzawa type algorithms for nonsymmetric generalized saddle point problems and their convergence properties. Our exact Uzawa algorithm can always converge without any prior estimate on the spectrum of two preconditioned subsystems involved. The convergence of our inexact Uzawa algorithm does not need the prior spectrum estimate of Schur complement, which may not be easy to achieve in practical applications. Numerical results of the algorithm on the Navier–Stokes problem are also presented. Copyright © 2015 John Wiley & Sons, Ltd.
Political marketing in Pakistan: exaggerated promises, delusive claims, marketable development projects and change advocacy
Authors: Yousaf Salman
Published: April 2015

The present study discusses the intricacies of the political landscape in Pakistan and its compatibility with the modern political marketing theory. The election campaigns of the three largest political parties Pakistan Muslim League Nawaz, Pakistan People's Party, and Pakistan Tehreek‐e‐Insaf in the general elections 2013 were critically analyzed in the print media to comprehend the political marketing trends in Pakistan. It was found out that that the three parties largely employed mutually exclusive strategies in order to garner the support of the electorate. The success ratio of the political parties in the general elections 2013 signifies the importance of certain advertising appeals, advertising themes, and aggressively attacking the opponents. The study also questioned the veracity of the exaggerated and delusive claims made in the advertisements. The findings have implications not only for future electioneering in Pakistan, but also other countries with similar demographics and socioeconomic setups. Copyright © 2015 John Wiley & Sons, Ltd.
Sexual functioning in breast cancer survivors experiencing body image disturbance
Authors: Boquiren Virginia M. , Esplen Mary Jane , Wong Jiahui , Toner Brenda , Warner Ellen , Malik Noorulain
Published: April 2015

Background

Breast cancer treatments and the traumatic nature of the cancer experience frequently elicit considerable sexual difficulties. Breast cancer survivors (BCS) experiencing body image (BI) issues may represent a vulnerable group for developing sexual dysfunction posttreatment. The current study explores sexual functioning (SF) in this unique clinical group.

Methods

A descriptive study assessed 127 BCS who were engaged in sexual activity. Standardized baseline measures included the following: BI Scale, BI after Breast Cancer Questionnaire, Female Sexual Function Index (FSFI), Kansas Marital Satisfaction Scale, and Functional Assessment of Cancer Therapy – Breast. Levels of SF were compared with BCS, heterogeneous cancer, and healthy female populations. Correlational analyses were conducted between SF, BI, relationship, and health‐related quality of life variables. Guided by a conceptual framework, regression analyses were conducted to determine significant demographic, clinical, and psychosocial predictors of sexual desire, satisfaction, and overall SF.

Results

Eighty‐three per cent of BCS met the FSFI clinical cutoff score for a sexual dysfunction. Participants exhibited poorer SF when compared with other female cancer and healthy groups. No significant correlations were found between BI questionnaire total scores and SF. BI after Breast Cancer Questionnaire – Body Stigma subscale showed significant associations with FSFI Arousal, Orgasm, Satisfaction (average r = −0.23), and overall SF (r = −0.25). Vaginal dryness (β = −0.50), body stigma (β = −0.24), and relationship satisfaction (β = 0.27) were significant predictors of overall SF.

Conclusion

Difficulties in SF appear to be highly prevalent in BCS experiencing BI disturbance posttreatment. Brief screening tools assessing SF should adopt a biopsychosocial model, which includes questions regarding vaginal dryness, relationship satisfaction, and body stigma issues. Copyright © 2015 John Wiley & Sons, Ltd.
Development of stapled helical peptides to perturb the Cdt1–Mcm6 interaction
Authors: Lee Jonghan Peter , Liu Changdong , Li Tianlu , Zhu Guang , Li Xuechen
Published: April 2015

Six all‐hydrocarbon‐stapled Cdt1 MBD‐derived peptides have been designed and synthesized to perturb the Cdt1–Mcm6 interaction, which is involved in DNA replication. Inconsistency between the helicity of the obtained peptidomimetics and their binding affinity has been observed. The helicity of 13‐amino acid stapled peptides increased, while their binding to Mcm6 was decreased. On the other hand, the 30‐amino acid stapled peptides exhibited decreased helicity but increased binding affinity. Copyright © 2015 European Peptide Society and John Wiley & Sons, Ltd.
The variation of temperature‐dependent carrier concentration and mobility in AlGaN/AlN/GaN heterostructure with SiN passivation
Authors: Ardali S. , Atmaca G. , Lisesivdin S. B. , Malin T. , Mansurov V. , Zhuravlev K. , Tiras E.
Published: April 2015

The effects of surface passivation effect on electron mobility and crystal structure in Al0.3Ga0.7N/AlN/GaN heterostructures are investigated by classical Hall effect measurements and an X‐ray diffraction method. Al0.3Ga0.7N/AlN/GaN heterostructures with different doping and layer structures were grown by molecular beam epitaxy with or without growing an in situ SiN passivation layer. The classical Hall effect measurements were carried out as a function of temperature in the range between T = 1.82 K and 270 K at a fixed magnetic field in dark conditions. The effect of doping of the barrier layer and replacing an AlN inter‐layer between the AlGaN barrier and the GaN layer, where the two‐dimensional electron gas is populated, on mobility and sheet carrier concentration were also determined.
Antifungal Activity of Ellagic Acid In Vitro and In Vivo
Authors: Li Zhi‐Jian , Guo Xin , Dawuti Gulina , Aibai Silafu
Published: April 2015

Ellagic acid (EA) has been shown to have antioxidant, antibacterial, and anti‐inflammatory activities. In Uighur traditional medicine, Euphorbia humifusa Willd is used to treat fungal diseases, and recent studies suggest that it is the EA content which is responsible for its therapeutic effect. However, the effects of EA on antifungal activity have not yet been reported. This study aimed to investigate the inhibitory effect of EA on fungal strains both in vitro and in vivo. The minimal inhibitory concentration (MIC) was determined by the National Committee for Clinical Laboratory Standards (M38‐A and M27‐A2) standard method in vitro. EA had a broad spectrum of antifungal activity, with MICs for all the tested dermatophyte strains between 18.75 and 58.33 µg/ml. EA was also active against two Candida strains, with MICs between 25.0 and 75.0 µg/ml. It was inactive against Candida glabrata. The susceptibility of six species of dermatophytes to EA was comparable with that of the commercial antifungal, fluconazole. The most sensitive filamentous species was Trichophyton rubrum (MIC = 18.75 µg/ml). Studies on the mechanism of action using an HPLC‐based assay and an enzyme linked immunosorbent assay showed that EA inhibited ergosterol biosynthesis and reduced the activity of sterol 14α‐demethylase P450 (CYP51) in the Trichophyton rubrum membrane, respectively. An in vivo test demonstrated that topical administration of EA (4.0 and 8.0 mg/cm2) significantly enhanced the cure rate in a guinea‐pig infection model of Trichophyton rubrum. The results suggest that EA has the potential to be developed as a natural antifungal agent. Copyright © 2015 John Wiley & Sons, Ltd.
Numerical Simulation of Burden and Gas Distributions Inside COREX Shaft Furnace
Authors: Kou Mingyin , Wu Shengli , Wang Geoff , Zhao Baojun , Cai Qingwu
Published: April 2015

Shaft furnace plays a very important role in the quantity and quality indexes of the COREX process. However, the simulation on the burden and gas distributions in COREX shaft furnace is still immature and hence needs further developed and improved. For instance, currently the geometric model is commonly used to simulate the COREX shaft furnace, but can only take into account one or two kinds of burden materials. To improve the simulation of the COREX shaft furnace, a three dimensional model of COREX shaft furnace is developed in this study. It applies the discrete element method (DEM) to a COREX‐3000 shaft furnace with the charging system whose size is the same as the actual one. The model simulates the charging process with four types of burdens together and then is used to investigate the effects of different distributor angles on the burden and gas distributions. Results show that the position of burden apex moves towards the wall and the height of burden profile decreases with the increase of distributor angle. Coke and flux roll away from the striking point, while ore segregates close to the striking point, and pellet always tends to move towards the central area. Coke and flux segregate more obviously in the wall area when the distributor angle is no larger than 10° while they segregate more in both the wall and the center areas when the angle is no smaller than 20°. The distributor angle is recommended to be no larger than 10° to control the central gas flow and be larger than 25° to prevent the peripheral gas from over developing.
Linear starch and hexanoic acid complexation evaluated by isothermal titration calorimetry
Authors: Arijaje Emily Oluwaseun , Jayanthi Srinivas , Kumar Thallapuranam Krishnaswamy Suresh , Wang Ya‐Jane
Published: April 2015

Linear starch form inclusion complexes with fatty acids through hydrophobic interaction. The complexation between starch and fatty acid is affected by many factors, such as starch degree of polymerization (DP), fatty acid structure, and complexation conditions. There is limited information on the use of isothermal titration calorimetry (ITC) in understanding starch‐fatty acid interactions. The effects of temperature and concentration of hexanoic acid on the complexation of debranched waxy maize starch and potato amylose were investigated using ITC. The starch samples were characterized for their molecular size distribution and iodine affinity. Potato amylose and debranched waxy maize starch displayed a major peak DP of 330 and 25, and iodine affinity of 2.9 and 13.9, respectively. The ITC titration data were fitted best to a one set of binding site model. Complexation was exothermic and spontaneous for all reactions based on changes in enthalpy of free energy (ΔG). The binding affinity (Ka) of debranched waxy maize starch for hexanoic acid decreased with an increase in temperature from 25 to 45°C. The Ka and number of binding sites (n) for debranched waxy maize exceeded those of potato amylose, indicating a higher complexation of debranched waxy maize for hexanoic acid. The number of binding sites (n) and enthalpy of binding (ΔH) values for both starches remained independent of temperature change. The ITC results demonstrated that debranched waxy maize starch was favored over potato amylose to complex hexanoic acid.
Glutamine Regulates Cardiac Progenitor Cell Metabolism and Proliferation
Authors: Salabei Joshua K. , Lorkiewicz Pawel K. , Holden Candice R. , Li Qianhong , Hong Kyung U. , Bolli Roberto , Bhatnagar Aruni , Hill Bradford G.
Published: April 2015

Autologous transplantation of cardiac progenitor cells (CPCs) alleviates myocardial dysfunction in the damaged heart; however, the mechanisms that contribute to their reparative qualities remain poorly understood. In this study, we examined CPC metabolism to elucidate the metabolic pathways that regulate their proliferative capacity. In complete growth medium, undifferentiated CPCs isolated from adult mouse heart proliferated rapidly (Td = 13.8 hours). CPCs expressed the Glut1 transporter and their glycolytic rate was increased by high extracellular glucose (Glc) concentration, in the absence of insulin. Although high Glc concentrations did not stimulate proliferation, glutamine (Gln) increased CPC doubling time and promoted survival under conditions of oxidative stress. In comparison with Glc, pyruvate (Pyr) or BSA-palmitate, Gln, when provided as the sole metabolic substrate, increased ATP-linked and uncoupled respiration. Although fatty acids were not used as respiratory substrates when present as a sole carbon source, Gln-induced respiration was doubled in the presence of BSA-palmitate, suggesting that Gln stimulates fatty acid oxidation. Additionally, Gln promoted rapid phosphorylation of the mTORC1 substrate, p70S6k, as well as retinoblastoma protein, followed by induction of cyclin D1 and cdk4. Inhibition of either mTORC1 or glutaminolysis was sufficient to diminish CPC proliferation, and provision of cell permeable α-ketoglutarate in the absence of Gln increased both respiration and cell proliferation, indicating a key role of Gln anaplerosis in cell growth. These findings suggest that Gln, by enhancing mitochondrial function and stimulating mTORC1, increases CPC proliferation, and that interventions to increase Gln uptake or oxidation may improve CPC therapy. Stem Cells  2015;33:2613—2627
Loss of Faap20 Causes Hematopoietic Stem and Progenitor Cell Depletion in Mice Under Genotoxic Stress
Authors: Zhang Tingting , Wilson Andrew F. , Mahmood Ali Abdullah , Namekawa Satoshi H. , Andreassen Paul R. , Ruhikanta Meetei Amom , Pang Qishen
Published: April 2015

20-kDa FANCA-associated protein (FAAP20) is a recently identified protein that associates with the Fanconi anemia (FA) core complex component, FANCA. FAAP20 contains a conserved ubiquitin-binding zinc-finger domain and plays critical roles in the FA-BRCA pathway of DNA repair and genome maintenance. The function of FAAP20 in animals has not been explored. Here, we report that deletion of Faap20 in mice led to a mild FA-like phenotype with defects in the reproductive and hematopoietic systems. Specifically, hematopoietic stem and progenitor cells (HSPCs) from Faap20−/− mice showed defects in long-term multilineage reconstitution in lethally irradiated recipient mice, with milder phenotype as compared to HSPCs from Fanca−/− or Fancc−/− mice. Faap20−/− mice are susceptible to mitomycin C (MMC)-induced pancytopenia. That is, acute MMC stress induced a significant progenitor loss especially the erythroid progenitors and megakaryocyte–erythrocyte progenitors in Faap20−/− mice. Furthermore, Faap20−/− HSPCs displayed aberrant cell cycle pattern during chronic MMC treatment. Finally, using Faap20−/− Fanca−/− double-knockout mice, we demonstrated a possible dominant effect of FANCA in the interaction between FAAP20 and FANCA. This novel Faap20 mouse model may be valuable in studying the regulation of the FA pathway during bone marrow failure progress in FA patients. Stem Cells  2015;33:2320–2330
Compatibility effect of titanium dioxide nanofiber on reinforced biobased nanocomposites: Thermal, mechanical, and morphology characterization
Authors: Dhandapani Suresh , Nayak Sanjay K. , Mohanty Smita
Published: April 2015

Titanium dioxide nanofiber (TNF) was synthesized from the anatase phase of titanium dioxide by the hydrothermal process. The synthesized TNF was reinforced with poly(trimethylene terephthalate)/poly(butylene adipate‐co‐terephthalate) blend to enhance the compatibility and improve the mechanical properties of the blend. The nanocomposite blends were prepared by using a twin‐screw extrusion process with different percentages (2.5%, 5.0%, 7.5%, and 10%) of TNF. The synthesized TNF phase structure was investigated by X‐ray diffraction, scanning electron microscopy, and Fourier‐transform infrared characterization. Enhanced compatibility was observed between the nanofiber and the polymer matrix, which was further confirmed by X‐ray diffraction and scanning electron microscopy analysis. The synthesized nanocomposites exhibited higher thermal stability and enhanced mechanical properties compared with the neat poly(trimethylene terephthalate)/poly(butylene adipate‐co‐terephthalate) matrix. J. VINYL ADDIT. TECHNOL., 22:529–538, 2016. © 2015 Society of Plastics Engineers
Goodput and throughput comparison of single‐hop and multi‐hop routing for IEEE 802.11 DCF‐based wireless networks under hidden terminal existence
Authors: Aydogdu Canan , Karasan Ezhan
Published: April 2015

We investigate how multi‐hop routing affects the goodput and throughput performances of IEEE 802.11 distributed coordination function‐based wireless networks compared with direct transmission (single hopping), when medium access control dynamics such as carrier sensing, collisions, retransmissions, and exponential backoff are taken into account under hidden terminal presence. We propose a semi‐Markov chain‐based goodput and throughput model for IEEE 802.11‐based wireless networks, which works accurately with both multi‐hopping and single hopping for different network topologies and over a large range of traffic loads. Results show that, under light traffic, there is little benefit of parallel transmissions and both single‐hop and multi‐hop routing achieve the same end‐to‐end goodput. Under moderate traffic, concurrent transmissions are favorable as multi‐hopping improves the goodput up to 730% with respect to single hopping for dense networks. At heavy traffic, multi‐hopping becomes unstable because of increased packet collisions and network congestion, and single‐hopping achieves higher network layer goodput compared with multi‐hop routing. As for the link layer throughput is concerned, multi‐hopping increases throughput 75 times for large networks, whereas single hopping may become advantageous for small networks. The results point out that the end‐to‐end goodput can be improved by adaptively switching between single hopping and multi‐hopping according to the traffic load and topology. Copyright © 2015 John Wiley & Sons, Ltd.
Transmission scheduling in a multi‐channel wireless network with bidirectional relaying links
Authors: Mohseni Maryam , Zhao Dongmei
Published: April 2015

Using network coding in a wireless network can potentially improve the network throughput. On the other hand, it increases the complexity of resource allocations as the quality of one transmission is affected by the link conditions of the transmitter to multiple receivers. In this work, we study time slot scheduling and channel allocations jointly for a network with bidirectional relaying links, where the two end nodes of each link can exchange data through a relay node. Two scenarios are considered when the relay node forwards packets to the end nodes. In the first scenario, the relay node always forwards network‐coded packets to both end nodes simultaneously; in the second scenario, the relay node opportunistically uses network coding for two‐way relaying and traditional one‐way relaying. For each scenario, an optimization problem is first formulated for maximizing the total network throughput. The optimum scheduling is not causal because it requires future information of channel conditions. We then propose heuristic scheduling schemes. The slot‐based scheduling maximizes the total transmission rate of all the nodes at each time slot, and the node‐based scheduling schedules transmissions based on achievable transmission rates of individual nodes at different channels. The node‐based one has lower complexity than the slot‐based one. Our results indicate that although the node‐based scheduling achieves slightly lower throughput than the slot‐based one, both the proposed scheduling schemes are very effective in the sense that the difference between their throughput and the optimum scheduling is relatively small in different network settings. Copyright © 2015 John Wiley & Sons, Ltd.
Controlling translation via modulation of tRNA levels
Authors: Wilusz Jeremy E.
Published: April 2015

Transfer RNAs (tRNAs) are critical adaptor molecules that carry amino acids to a messenger RNA (mRNA) template during protein synthesis. Although tRNAs have commonly been viewed as abundant ‘house‐keeping’ RNAs, it is becoming increasingly clear that tRNA expression is tightly regulated. Depending on a cell's proliferative status, the pool of active tRNAs is rapidly changed, enabling distinct translational programs to be expressed in differentiated versus proliferating cells. Here, I highlight several post‐transcriptional regulatory mechanisms that allow the expression or functions of tRNAs to be altered. Modulating the modification status or structural stability of individual tRNAs can cause those specific tRNA transcripts to selectively accumulate or be degraded. Decay generally occurs via the rapid tRNA decay pathway or by the nuclear RNA surveillance machinery. In addition, the CCA‐adding enzyme plays a critical role in determining the fate of a tRNA. The post‐transcriptional addition of CCA to the 3′ ends of stable tRNAs generates the amino acid attachment site, whereas addition of CCACCA to unstable tRNAs prevents aminoacylation and marks the tRNA for degradation. In response to various stresses, tRNAs can accumulate in the nucleus or be further cleaved into small RNAs, some of which inhibit translation. By implementing these various post‐transcriptional control mechanisms, cells are able to fine‐tune tRNA levels to regulate subsets of mRNAs as well as overall translation rates. WIREs RNA 2015, 6:453–470. doi: 10.1002/wrna.1287

This article is categorized under:

Translation > Translation Regulation

RNA Processing > tRNA Processing

RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms
Translating Professional Obligations to Care for Patients With Ebola Virus Disease Into Practice in Nonepidemic Settings
Authors: Sugarman Jeremy , Kass Nancy , Rushton Cynda H. , Hughes Mark T. , Kirsch Thomas D.
Published: April 2015

Determining how clinicians should meet their professional obligations to treat patients with Ebola virus disease in nonepidemic settings necessitates considering measures to minimize risks to clinicians, the context of care, and fairness. Minimizing risks includes providing appropriate equipment and training, implementing strategies for reducing exposure to infectious material, identifying a small number of centers to provide care, and determining which risky procedures should be used when they pose minimal likelihood of appreciable clinical benefit. Factors associated with the clinical environment, such as the local prevalence of the disease, the nature of the setting, and the availability of effective treatment, are also relevant to obligations to treat. Fairness demands that the best possible medical care be provided for health care professionals who become infected and that the rights and interests of relevant stakeholders be addressed through policy-making processes. Going forward it will be essential to learn from current approaches and to modify them based on data. (Disaster Med Public Health Preparedness. 2015;9:527–530)
Enhanced effects from tiny flexible in-wall blips and shear flow
Authors: Pruessner Luisa , Smith Frank
Published: April 2015

Fluid motion at high Reynolds number over a flexible in-wall blip (a compliant bump or dip in an otherwise fixed wall) is considered theoretically for a very short blip buried low inside a boundary layer. Only the near-wall shear of the oncoming flow affects the local motion past the tiny blip. Slowly evolving features are examined first to allow for variations in the incident flow. Linear and nonlinear solutions show that at certain parameter values (eigenvalues) intensifications occur in which the interactive effect on flow and blip shape is larger by an order of magnitude than at most parameter values. Similar findings apply to the boundary layer with several tiny blips present or to channel flows with blips of almost any length. These intensifications lead on to fully nonlinear unsteady motion as a second stage, after some delay, thus combining with finite-time breakups to form a distinct path into transition of the flow.
New edrioasterine and astrocystitid (Echinodermata: Edrioasteroidea) from the Ninemile Shale (Lower Ordovician), central Nevada
Authors: Sprinkle James , Sumrall Colin D.
Published: April 2015

The new edrioasterinePseudedriophus guensburgin. gen. n. sp., is described from the Lower Ordovician Ninemile Shale of central Nevada based on three complete to partial small specimens, a well-preserved large ambulacrum, and an isolated ambulacral floor plate. The weathered-out holotype of this edrioasterine exposes the bottom surface of the theca that bears an aboral collar, peduncular stalk, and attachment disk, features that are poorly known in this clade. These specimens were found with a single specimen of a new edrioblastoid,Porosublastus inexpectusn. gen. n. sp., only the second edrioblastoid ever found in the Early Ordovician. Some of the ambulacral cover plates are stripped off one of the ambulacal grooves, revealing new information about how the ambulacra are built in this rare group of bud-shaped edrioasteroids.
Responses to colour and host odour cues in three cereal pest species, in the context of ecology and control
Authors: Arnold S.E.J. , Stevenson P.C. , Belmain S.R.
Published: April 2015

Many insects show a greater attraction to multimodal cues, e.g. odour and colour combined, than to either cue alone. Despite the potential to apply the knowledge to improve control strategies, studies of multiple stimuli have not been undertaken for stored product pest insects. We tested orientation towards a food odour (crushed white maize) in combination with a colour cue (coloured paper with different surface spectral reflectance properties) in three storage pest beetle species, using motion tracking to monitor their behaviour. While the maize weevil,Sitophilus zeamais(Motsch.), showed attraction to both odour and colour stimuli, particularly to both cues in combination, this was not observed in the bostrichid pestsRhyzopertha dominica(F.) (lesser grain borer) orProstephanus truncatus(Horn) (larger grain borer). The yellow stimulus was particularly attractive toS. zeamais, and control experiments showed that this was neither a result of the insects moving towards darker-coloured areas of the arena, nor their being repelled by optical brighteners in white paper. Visual stimuli may play a role in location of host material byS. zeamais, and can be used to inform trap design for the control or monitoring of maize weevils. The lack of visual responses by the two grain borers is likely to relate to their different host-seeking behaviours and ecological background, which should be taken into account when devising control methods.
Trapped-electron runaway effect
Authors: Nilsson E. , Decker J. , Fisch N. J. , Peysson Y.
Published: April 2015

In a tokamak, trapped electrons subject to a strong electric field cannot run away immediately, because their parallel velocity does not increase over a bounce period. However, they do pinch toward the tokamak center. As they pinch toward the center, the trapping cone becomes more narrow, so eventually they can be detrapped and run away. When they run away, trapped electrons will have a very different signature from circulating electrons subject to the Dreicer mechanism. The characteristics of what are called trapped-electron runaways are identified and quantified, including their distinguishable perpendicular velocity spectrum and radial extent.
All's good in a famine?Hydrobia ulvaeas a secondary prey for juveniles of Iceland moonsnailsAmauropsis islandicaat the White Sea sandflats
Authors: Aristov Dmitriy , Varfolomeeva Marina , Puzachenko Georgii
Published: April 2015

Many size-selective predators switch their diet during ontogeny. At the White Sea, the adult moonsnailsAmauropsis islandicafeed mostly onMacoma balthicaclams. The diet of juveniles was largely unknown. We conducted a field survey and a caging experiment to find out if juvenile moonsnails can prey onHydrobia ulvae, and whether they prefer this snail to their usual prey. Live molluscs and their intact or perforated shells were collected from 34 sediment cores. We exposed the single-prey cages with 50Macoma(MP) or 50Hydrobia(HP) together with fiveAmauropsisjuveniles, as well as the cages where both prey species were in a 25:25 proportion (HMP). While liveHydrobiawas more abundant in the natural assemblages,AmauropsispreferredMacoma, as indicated by proportions of perforated shells. The caging experiment produced similar results. Per capitaMacomaconsumption rate was significantly higher thanHydrobiaconsumption rate (6.4 ± 0.5 mg day−1ind.−1vs.1.4±0.2 mg day−1ind.−1in MP and HP respectively). Prey consumption rates in the single-prey treatments were higher than in mixed-prey cages regardless of prey species. Different mechanisms explain this variation: forHydrobiait is a consequence of the dietary shift, while forMacomait reflects the ‘floor’ effect in HMP cages, where virtually allMacomahad been drilled by the end of exposure term. WhileMacomais the preferable prey of youngAmauropsis, Hydrobiacan supplement the diet of juveniles whenMacomais scarce in certain locations.