bluuebunny/crossref_metadata_2025 huggingface dataset:
Transforming growth factor‐β in liver cancer stem cells and regeneration
Authors: Rao Shuyun , Zaidi Sobia , Banerjee Jaideep , Jogunoori Wilma , Sebastian Raul , Mishra Bibhuti , Nguyen Bao‐Ngoc , Wu Ray‐Chang , White Jon , Deng Chuxia , Amdur Richard , Li Shulin , Mishra Lopa
Published: July 2017

Cancer stem cells have established mechanisms that contribute to tumor heterogeneity as well as resistance to therapy. Over 40% of hepatocellular carcinomas (HCCs) are considered to be clonal and arise from a stem‐like/cancer stem cell. Moreover, HCC is the second leading cause of cancer death worldwide, and an improved understanding of cancer stem cells and targeting these in this cancer are urgently needed. Multiple studies have revealed etiological patterns and multiple genes/pathways signifying initiation and progression of HCC; however, unlike the transforming growth factor β (TGF‐β) pathway, loss of p53 and/or activation of β‐catenin do not spontaneously drive HCC in animal models. Despite many advances in cancer genetics that include identifying the dominant role of TGF‐β signaling in gastrointestinal cancers, we have not reached an integrated view of genetic mutations, copy number changes, driver pathways, and animal models that support effective targeted therapies for these common and lethal cancers. Moreover, pathways involved in stem cell transformation into gastrointestinal cancers remain largely undefined. Identifying the key mechanisms and developing models that reflect the human disease can lead to effective new treatment strategies. In this review, we dissect the evidence obtained from mouse and human liver regeneration, and mouse genetics, to provide insight into the role of TGF‐β in regulating the cancer stem cell niche. (Hepatology Communications 2017;1:477–493)
Different miR‐21‐3p isoforms and their different features in colorectal cancer
Authors: Jiao Weijuan , Leng Xueqin , Zhou Qun , Wu Yayun , Sun Lina , Tan Yan , Ni Hengli , Dong Xiaoqiang , Shen Tong , Liu Yao , Li Jianming
Published: July 2017

MiR‐21, the only microRNA (miRNA) found to be overexpressed in any type of solid tumor, its guide stand, miR‐21‐5p, has been studied a lot in colorectal cancer (CRC); however, few researchers focused on its passenger strand, miR‐21‐3p. In our study, based on The Cancer Genome Atlas (TCGA) data, we found that there were more varieties and quantities of miR‐21‐3p isoforms in microsatellite instability (MSI)‐type CRC. We further examined the role of miR‐21‐3p by in vitro and in vivo studies. MiR‐21‐3p may be an oncogene in CRC by promoting cellular mobility through epithelial–mesenchymal transition. However, different isoforms, especially miR‐21‐3p 0 | 2, may be a favorable prognostic marker for CRC survival, probably due to increased complementary effect of miR‐21‐5p and/or target genes. Further study investigating the underlying mechanism of miRNA isoforms is needed.
In vivo placental MRI shape and textural features predict fetal growth restriction and postnatal outcome
Authors: Dahdouh Sonia , Andescavage Nickie , Yewale Sayali , Yarish Alexa , Lanham Diane , Bulas Dorothy , du Plessis Adre J , Limperopoulos Catherine
Published: July 2017

Purpose

To investigate the ability of three‐dimensional (3D) MRI placental shape and textural features to predict fetal growth restriction (FGR) and birth weight (BW) for both healthy and FGR fetuses.

Materials and Methods

We recruited two groups of pregnant volunteers between 18 and 39 weeks of gestation; 46 healthy subjects and 34 FGR. Both groups underwent fetal MR imaging on a 1.5 Tesla GE scanner using an eight‐channel receiver coil. We acquired T2‐weighted images on either the coronal or the axial plane to obtain MR volumes with a slice thickness of either 4 or 8 mm covering the full placenta. Placental shape features (volume, thickness, elongation) were combined with textural features; first order textural features (mean, variance, kurtosis, and skewness of placental gray levels), as well as, textural features computed on the gray level co‐occurrence and run‐length matrices characterizing placental homogeneity, symmetry, and coarseness. The features were used in two machine learning frameworks to predict FGR and BW.

Results

The proposed machine‐learning based method using shape and textural features identified FGR pregnancies with 86% accuracy, 77% precision and 86% recall. BW estimations were 0.3 ± 13.4% (mean percentage error ± standard error) for healthy fetuses and ‐2.6 ± 15.9% for FGR.

Conclusion

The proposed FGR identification and BW estimation methods using in utero placental shape and textural features computed on 3D MR images demonstrated high accuracy in our healthy and high‐risk cohorts. Future studies to assess the evolution of each feature with regard to placental development are currently underway.

Level of Evidence: 2

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2018;47:449–458.
Effects of eddy currents on selective spectral editing experiments at 3T
Authors: Oeltzschner Georg , Snoussi Karim , Puts Nicolaas A. , Mikkelsen Mark , Harris Ashley D. , Pradhan Subechhya , Tsapkini Kyrana , Schär Michael , Barker Peter B. , Edden Richard A.E.
Published: July 2017

Purpose

To investigate frequency‐offset effects in edited magnetic resonance spectroscopy (MRS) experiments arising from B0 eddy currents.

Materials and Methods

Macromolecule‐suppressed (MM‐suppressed) γ‐aminobutyric acid (GABA)‐edited experiments were performed at 3T. Saturation‐offset series of MEGA‐PRESS experiments were performed in phantoms, in order to investigate different aspects of the relationship between the effective editing frequencies and eddy currents associated with gradient pulses in the sequence. Difference integrals were quantified for each series, and the offset dependence of the integrals was analyzed to quantify the difference in frequency (Δf) between the actual vs. nominal expected saturation frequency.

Results

Saturation‐offset N‐acetyl‐aspartate‐phantom experiments show that Δf varied with voxel orientation, ranging from 10.4 Hz (unrotated) to 6.4 Hz (45° rotation about the caudal–cranial axis) and 0.4 Hz (45° rotation about left–right axis), indicating that gradient‐related B0 eddy currents vary with crusher‐gradient orientation. Fixing the crusher‐gradient coordinate‐frame substantially reduced the orientation dependence of Δf (to ∼2 Hz). Water‐suppression crusher gradients also introduced a frequency offset, with Δf = 0.6 Hz (“excitation” water suppression), compared to 10.2 Hz (no water suppression). In vivo spectra showed a negative edited “GABA” signal, suggesting Δf on the order of 10 Hz; with fixed crusher‐gradient coordinate‐frame, the expected positive edited “GABA” signal was observed.

Conclusion

Eddy currents associated with pulsed field gradients may have a considerable impact on highly frequency‐selective spectral‐editing experiments, such as MM‐suppressed GABA editing at 3T. Careful selection of crusher gradient orientation may ameliorate these effects.

Level of Evidence: 2

Technical Efficacy: Stage 1

J. Magn. Reson. Imaging 2018;47:673–681.
Polymorphisms of miR‐146a, miR‐149, miR‐196a2, and miR‐499 are associated with osteoporotic vertebral compression fractures in Korean postmenopausal women
Authors: Ahn Tae‐Keun , Kim Jung‐Oh , Kumar Hemant , Choi Hyemi , Jo Min‐Jae , Sohn Seil , Ropper Alexander E. , Kim Nam‐Keun , Han In‐Bo
Published: July 2017

Genetic factors have been shown to be a small but significant predictor for osteoporosis and osteoporotic fracture risk. We performed a case–control association study to determine the association between miR‐146a, miR‐149, miR‐196a2, and miR‐499 polymorphisms and osteoporotic vertebral compression fracture (OVCF) susceptibility. In total, 286 unrelated postmenopausal Korean women (57 with OVCFs, 55 with non‐OVCFs, and 174 healthy controls) were recruited. All subjects underwent dual energy X‐ray absorptiometry to determine BMD at the lumbar spine and femoral neck. We focused on four single nucleotide polymorphisms (SNPs) of pre‐miRNA sequences including miR‐146aC>G (rs2910164), miR‐149T>C (rs2292832), miR‐196a2T>C (rs11614913), and miR‐499A>G (rs3746444). Genotype frequencies of these four SNPs were determined using polymerase chain reaction‐restriction fragment length polymorphism analysis. The TT genotype of miR‐149aT>C was less frequent in subjects with OVCFs, suggesting a protective effect against OVCF risk (Odds ratio [OR], 0.435; 95% confidence interval [CI], 0.22–0.85, p = 0.014), whereas the miR‐146aCG/ miR‐196a2TC combined genotype was more frequent in OVCF patients (OR, 5.163; 95%CI, 1.057–25.21, p = 0.043), suggesting an increase in OVCF risk. Additionally, combinations of miR‐146a, ‐149, ‐196a2, and ‐449 showed a significant association with increased prevalence of OVCFs in postmenopausal women. In particular, the miR‐146aG/‐149T/‐196a2C/‐449G allele combination was significantly associated with an increased risk of OVCF (OR, 35.01; 95% CI, 1.919–638.6, p = 0.001). Our findings suggest that the TT genotype of miR‐149aT>C may contribute to decreased susceptibility to OVCF in Korean postmenopausal women. Conversely, the miR‐146aCG/ miR‐196a2TC combined genotype and the miR‐146aG/‐149T/‐196a2C/‐449G allele combination may contribute to increased susceptibility to OVCF. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:244–253, 2018.
Metabolomic analysis reveals the composition differences in 13 Chinese tea cultivars of different manufacturing suitabilities
Authors: Li Pengliang , Dai Weidong , Lu Meiling , Xie Dongchao , Tan Junfeng , Yang Chen , Zhu Yin , Lv Haipeng , Peng Qunhua , Zhang Yue , Guo Li , Ni Dejiang , Lin Zhi
Published: July 2017

BACKGROUND

Green tea and black tea are manufactured using appropriate tea cultivars in China. However, the metabolite differences relating to the manufacturing suitability of tea cultivars are unclear. In the present study, we performed a non‐targeted metabolomic analysis on 13 Chinese tea cultivars using ultra‐high performance liquid chromatography coupled with quadrupole‐time‐of‐flight mass spectrometry to investigate comprehensively the metabolite differences between cultivars suitable for manufacturing green tea (GT cultivars) and cultivars suitable for manufacturing both green tea and black tea (G&BT cultivars).

RESULTS

Multivariate statistical analysis and cluster analysis divided the 13 cultivars into two groups, namely GT cultivars and G&BT cultivars, which correlated with their manufacturing suitability. The GT cultivars contained higher levels of flavonoid glycosides, whereas the G&BT cultivars contained higher levels of catechins, dimeric catechins, phenolic acids and alkaloids.

CONCLUSION

Metabolic pathway analysis revealed that the flavonoid pathway inclined toward the synthesis of flavonoid glycosides in GT cultivars, whereas it inclined toward the synthesis of catechins and phenolic acids in G&BT cultivars. The results of the present study will be helpful for discriminating the manufacturing suitability of tea cultivars and investigating their breeding. © 2017 Society of Chemical Industry
Self‐Regulation Shift Theory: A Dynamic Systems Approach to Traumatic Stress
Authors: Benight Charles C. , Shoji Kotaro , Delahanty Douglas L.
Published: July 2017

Self‐regulation shift theory (SRST) is a threshold theory explaining self‐regulation following trauma that utilizes nonlinear dynamics to capture systemic shifts in trauma adaptation. Cusp catastrophe modeling tests nonlinear changes in an outcome (e.g., posttraumatic distress) based on an identified bifurcation factor under specific conditions (i.e., asymmetry variables). We evaluated two cusp models in a motor vehicle accident (MVA) database and then confirmed findings within a similar dataset. Based on SRST, we tested coping self‐efficacy (CSE) as the bifurcation factor and a set of asymmetry controlling variables. Results demonstrated significant cusp models with CSE as a consistent bifurcation factor in all models. When participants reported lower peritraumatic dissociation, early lower CSE was a significant bifurcation factor for 3‐month trauma symptoms in Sample 1, R2 = .18. The cusp model for changes in symptoms from 30 days to 3 months showed CSE as a significant bifurcation variable with higher levels of avoidant coping (R2 = .27). In a separate sample, early lower CSE was again a significant bifurcation variable with lower injury severity (R2 = .52). Results support the importance of self‐regulatory appraisals in nonlinear shifts in posttraumatic stress symptoms 3 months post‐MVA. Theoretical and practical implications are discussed.
An enhanced bubble size sensor for long‐term ebullition studies
Authors: Delwiche Kyle , Hemond Harold F.
Published: July 2017

Methane ebullition from freshwater sediments is a significant source of greenhouse gas to the atmosphere. Methane bubble size determines the fraction of methane that dissolves into the water column instead of entering the atmosphere, but current methods to measure bubble sizes in situ are limited. Previously, we reported the design for a novel optical bubble size sensor capable of measuring methane bubble sizes in situ. Here, we report sensor enhancements to allow for continuous long‐term sensor deployment, uninterrupted data collection under high ebullition flux, and improved bubble volume measurement accuracy. The enhanced design includes a data and power cable running from the sensor to a custom data buoy housing batteries and an SD memory card. Batteries and SD cards are replaced every 2–4 weeks through the data buoy, allowing for continuous, undisturbed sensor deployment. In addition, sensor parameters have been tuned to reduce error from particle intrusion and fluctuations in raw signals that were observed during transit of some bubbles through the sensor. Field data show that on average the sensor measures cumulative bubble volumes equaling approximately 86% of collected gas volumes. We discuss potential mechanisms of remaining error, some of which may be due to zooplankton intrusion, and suggest directions for future sensor enhancements.
FDG PET, dopamine transporter SPECT, and olfaction: Combining biomarkers in REM sleep behavior disorder
Authors: Meles Sanne K. , Vadasz David , Renken Remco J. , Sittig‐Wiegand Elisabeth , Mayer Geert , Depboylu Candan , Reetz Kathrin , Overeem Sebastiaan , Pijpers Angelique , Reesink Fransje E. , van Laar Teus , Heinen Lisette , Teune Laura K. , Höffken Helmut , Luster Marcus , Kesper Karl , Adriaanse Sofie M. , Booij Jan , Leenders Klaus L. , Oertel Wolfgang H.
Published: July 2017

Background

Idiopathic REM sleep behavior disorder is a prodromal stage of Parkinson's disease and dementia with Lewy bodies. Hyposmia, reduced dopamine transporter binding, and expression of the brain metabolic PD‐related pattern were each associated with increased risk of conversion to PD. The objective of this study was to study the relationship between the PD‐related pattern, dopamine transporter binding, and olfaction in idiopathic REM sleep behavior disorder.

Methods

In this cross‐sectional study, 21 idiopathic REM sleep behavior disorder subjects underwent 18F‐fluorodeoxyglucose PET, dopamine transporter imaging, and olfactory testing. For reference, we included 18F‐fluorodeoxyglucose PET data of 19 controls, 20 PD patients, and 22 patients with dementia with Lewy bodies. PD‐related pattern expression z‐scores were computed from all PET scans.

Results

PD‐related pattern expression was higher in idiopathic REM sleep behavior disorder subjects compared with controls (P = 0.048), but lower compared with PD (P = 0.001) and dementia with Lewy bodies (P < 0.0001). PD‐related pattern expression was higher in idiopathic REM sleep behavior disorder subjects with hyposmia and in subjects with an abnormal dopamine transporter scan (P < 0.05, uncorrected).

Conclusion

PD‐related pattern expression, dopamine transporter binding, and olfaction may provide complementary information for predicting phenoconversion. © 2017 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
Carbon nanotube size effect on the mechanical properties and toughness of nanocomposites
Authors: Hsieh Tsung‐Han , Huang Yau‐Shian , Shen Ming‐Yuan
Published: July 2017

To evaluate the nanotube size effect on the material properties of nanotube‐modified nanocomposites, two types of multi‐walled carbon nanotubes with various dimensions were used to form nanocomposites, and then the mechanical properties and the toughness were measured. The well‐known issue of nanotube dispersion was examined using various microscopic observations, and an ideal dispersion process was identified. The results revealed that adding nanotubes led to increases in the Young's modulus and toughness of the nanocomposites. A maximum measured value of the fracture energy was recorded at 237 J m−2 for the nanocomposite toughened with 0.5 wt% of the longer nanotubes. This is ∼90% higher than the unmodified epoxy, and a 40% increase in the fracture energy compared with the sample containing the shorter nanotubes under identical nanotube loading. This indicated that the length of the nanotubes severely affected the toughness of the nanotube‐modified polymers. However, the increased moduli, triggered by the addition of the various types of carbon nanotubes, were similar. The toughening mechanisms were identified via studying the fracture surfaces of the nanocomposites. POLYM. COMPOS., 39:E1072–E1086, 2018. © 2017 Society of Plastics Engineers
Correlating charge fluence with nanoparticle formation during in situ plasma synthesis of nanocomposite films
Authors: Ghosh Souvik , Boris David R. , Hernández Sandra C. , Zorman Christian A. , Walton Scott G. , Sankaran R. Mohan
Published: July 2017

Plasmas enable the fabrication of nanocomposites via in situ reduction of metal precursors dispersed in polymer films. The mechanism for reduction has not yet been revealed and it is not known how plasma parameters affect nanoparticle formation. Here, we present a systematic study using a low‐pressure, pulsed electron beam generated argon plasma to treat silver cation‐containing polyacrylic acid films. The background pressure, treatment time, period, and pulse width are varied to influence charged species generation. We show a direct correlation between nanoparticle density, as assessed by ultraviolet‐visible absorbance analysis, and the charge fluence. Although the experiments could not separate the specific role of ions and electrons, our results demonstrate the importance of charged species to nanoparticle formation.
A computational method for selecting short peptide sequences for inorganic material binding
Authors: Nayebi Niloofar , Cetinel Sibel , Omar Sara Ibrahim , Tuszynski Jack A. , Montemagno Carlo
Published: July 2017

Discovering or designing biofunctionalized materials with improved quality highly depends on the ability to manipulate and control the peptide‐inorganic interaction. Various peptides can be used as assemblers, synthesizers, and linkers in the material syntheses. In another context, specific and selective material‐binding peptides can be used as recognition blocks in mining applications. In this study, we propose a new in silico method to select short 4‐mer peptides with high affinity and selectivity for a given target material. This method is illustrated with the calcite (104) surface as an example, which has been experimentally validated. A calcite binding peptide can play an important role in our understanding of biomineralization. A practical aspect of calcite is a need for it to be selectively depressed in mining sites.
Protein features as determinants of wild‐type glycoside hydrolase thermostability
Authors: Geertz‐Hansen Henrik Marcus , Kiemer Lars , Nielsen Morten , Stanchev Kiril , Blom Nikolaj , Brunak Søren , Petersen Thomas Nordahl
Published: July 2017

Thermostable enzymes for conversion of lignocellulosic biomass into biofuels have significant advantages over enzymes with more moderate themostability due to the challenging application conditions. Experimental discovery of thermostable enzymes is highly cost intensive, and the development of in‐silico methods guiding the discovery process would be of high value. To develop such an in‐silico method and provide the data foundation of it, we determined the melting temperatures of 602 fungal glycoside hydrolases from the families GH5, 6, 7, 10, 11, 43, and AA9 (formerly GH61). We, then used sequence and homology modeled structure information of these enzymes to develop the ThermoP melting temperature prediction method. Futhermore, in the context of thermostability, we determined the relative importance of 160 molecular features, such as amino acid frequencies and spatial interactions, and exemplified their biological significance. The presented prediction method is made publicly available at http://www.cbs.dtu.dk/services/ThermoP.
Polymeric Schiff Base Metal Complexes Based on Thermo‐Responsive PNIPAM: Synthesis, Characterization and Catalytic Activity
Authors: Ghasemi Soheila , Andami Zahra
Published: July 2017

The preparation and characterization of some polymeric Schiff base‐metal complexes based on thermo‐responsive copolymer composed of N‐isopropylacrylamide and acrylamide (poly (NIPAM‐co‐AAM)) is explained. Poly (NIPAM‐co‐AAM) was produced via conventional radical polymerization method with phase transition around 35 °C. The copolymer was amino modified followed by reaction with different aldehydes to produce polymeric Schiff‐bases and utilized as an absorbent for heavy metals. The polymeric complexes were used in the role of catalyst for hydrogen peroxide decomposition as a sample reaction. The significant characteristic of these thermo‐responsive copolymers is facilitating the catalyst recovery from the reaction components by heating above the lower critical solution temperature (LCST). The effect of different parameters such as ligand and metal ion type and reaction temperature was explored on the activity of these polymeric metal catalysts.
The Neglected Significant Role for Graphene‐Based Acetylene Hydrochlorination Catalysts — Intrinsic Graphene Defects
Authors: Zhao Fei , Kang Lihua
Published: July 2017

In the present work, density functional theory(DFT) calculations at M062X/cc‐pVDZ level were performed aim to investigate the activity of defective graphenes catalyze acetylene hydrochlorination reaction. Owing to the narrowed HOMO‐LUMO energy gaps, the adsorption ability of C2H2 and HCl on three kind of defective graphenes(mono‐vacancy graphene(MVG), di‐vacancy graphene(DVG) and Stone‐wales defect graphene(SWDG)) were all enhanced compared with perfective graphene(PG). Meanwhile, the adsorption strength of the two adsorbates decreased followed by the order of DVG > MVG > SWDG, and the strength of C2H2 is tougher than HCl adsorb on MVG and DVG, but opposite in SWDG. The reaction mechanisms are similar and reacted at the site of the mutual bond C5‐C6 which belongs to 5‐MR and 6‐MR. MVG possess the lowest activation barrier of 39.46 kcal/mol, lower than DVG and SWDG. Hence, the catalytic contribution of graphene defects for acetylene hydrochlorination reaction should not be ignored.
Graphene Derivatives Doped with Nickel Ferrite Nanoparticles as Excellent Microwave Absorbers in Soft Nanocomposites
Authors: Pawar Shital Patangrao , Gandi Mounika , Arief Injamamul , Krause Beate , Pötschke Petra , Bose Suryasarathi
Published: July 2017

Herein, we report the development of soft polymeric composites containing multiwall carbon nanotubes (MWNTs, 1–3 wt%) and graphene derivatives doped with nickel ferrite nanoparticles (rGO@NF, 10 wt%) as lightweight microwave absorbers. The soft nanocomposites were designed using melt‐mixed blends of varying compositions of PC (polycarbonate) and SAN (poly styrene acrylonitrile) by compartmentalized functional nanoparticles in one of the components of the blend (here PC). Maximum attenuation of the incoming electromagnetic (EM) radiation mainly through absorption was achieved. The hetero‐dielectric media at microscopic length scale in the PC component provided large interfaces which facilitated multiple scattering thereby attenuating the incoming EM radiation. This strategy of positioning the functional nanoparticles in one of the components in the blends resulted in significantly enhanced shielding effectiveness (SE), at any given concentration of MWNTs, in contrast to PC based composites. This enhancement in SE was realized in the special morphology of the bicomponent PC/SAN=60/40 wt% blends where both the components are continuous. The enhanced SE in co‐continuous blends is due to combined effect of enhanced electrical conductivity (more precisely due to interconnected network of the nanoparticles) and the presence of a hetero‐dielectric media generating large scattering interfaces. For instance, the PC/SAN (60/40 wt%) co‐continuous blend containing 3 wt% MWNTs and 10 wt% rGO@NF manifested in a total shielding effectiveness (SET) of −32.3 dB (i. e. more than 99.9 % attenuation of incoming EM radiation) mainly through absorption.
Modified Imidazolium‐Based Ionic Liquids With Improved Chemical Stability Against Lithium Metal
Authors: Schmitz Paulo , Kolek Martin , Pyschik Marcelina , Jalkanen Kirsi , Nowak Sascha , Winter Martin , Bieker Peter
Published: July 2017

Chemical instability against metallic lithium of imidazolium cation‐based ionic liquids (ILs) such as 1‐butyl‐3‐methylimidazolium bis(trifluoromethanesulfonyl)imide ([C4MIm]TFSI) has been reported in literature previously. In this work, modified imidazolium cation‐based ionic liquids are shown, in which the acidic proton at the C‐2 position of the imidazolium ring is replaced by methyl groups. 1‐butyl‐2,3‐dimethylimidazolium bis(trifluoromethanesulfonyl)imide ([C4MMIm]TFSI) and 1‐butyl‐2,3,4,5‐tetramethylimidazolium bis(trifluoromethanesulfonyl)imide ([C44MIm]TFSI) are found to prevent the formation of N‐heterocyclic carbenes and thus improve the electrochemical performance of electrolytes including these ILs. Furthermore, possible decomposition products of the modified imidazolium cations are characterized.
Connection bridge effect on a DNA‐like two‐spiral‐up‐tower building
Authors: Nie Xin , Xiao Congzhen , Du Yixin , Kang Zhihong , Yang Yue
Published: July 2017

In the recent years, more and more great ideas about architectural design were inspired from bionics, that is, the China National Stadium, Taipei 101, and India Lotus Temple were first inspired from bird's nest, bamboo, and blooming lotus, respectively. However, being a feast to the eyes, those innovative architectures with complex structural behavior and unknown seismic performance are always being a challenge to structural engineers. Hereinafter, a DNA‐like high‐rise building with two separate spiral‐up towers was first outlined, in which each of the tower consist of an interior reinforced concrete core with inserted steel columns and an exterior composite frame made of steel beams and steel pipe–concrete columns. To study the influence of the connection bridges on the seismic performance under different level of earthquake excitation and torsional effect under gravity load, the load transfer mechanism of vertical force and lateral force was conducted, and a finite element model was built with parametrical studies. It can be concluded from the results from the parametrical studies that the drift angle was sharply decreased at the locations where the connection bridges combines two single towers, indicating that the lateral confinement effect of the connection bridges not only strengthen the whole structure but also leads to a discontinuity of the structural stiffness.
Characterizing teacher attention to student thinking: A role for epistemological messages
Authors: Russ Rosemary S.
Published: July 2017

Although research and policy suggest science and mathematics teachers should attend to their student's thinking during instruction, our field has inadequately defined what that means in relation to our ultimate goals for the practice. Here I present a theoretical argument that, in making their definitions, researchers should leverage the ways students understand such attention by characterizing teacher attention based on the epistemological messages it sends students about the nature of knowledge and learning in the classroom. Using data collected from high school science and mathematics teachers with a new video‐capture methodology, I present an analysis of variability in epistemological messages of teacher attention to illustrate work could unfold if we as researchers took up the theoretical claims made in this work. In doing so, I endeavor to draw the construct of epistemological messages into our collective conversations about teacher attention, and provide a starting point for our field to begin debating the most productive ways to study and unpack the epistemological messages we value in that teacher attention. I conclude by demonstrating the feasibility of using these messages to distinguish the types of teacher attention our field wants to develop and encourage in teacher education. © 2017 Wiley Periodicals, Inc. J Res Sci Teach 55: 94–120, 2018
Identifying Symptoms of Distress in Youth Living with Neurofibromatosis Type 1 (NF1)
Authors: Wiener Lori , Battles Haven , Bedoya Sima Zadeh , Baldwin Andrea , Widemann Brigitte C. , Pao Maryland
Published: July 2017

Children and adolescents with Neurofibromatosis type 1 (NF1) are at increased risk for wide‐ranging behavioral, developmental, and cognitive impairments and decreased quality of life. To date, no psychosocial screening tool has been developed to quickly assess the symptoms that 1) can be addressed during routine medical appointments in children with NF1, 2) can produce interpretable and actionable results, 3) can be integrated into medical care, and 4) can quickly identify patients at risk in order to better address that the provision of appropriate care are available. This study was conducted to test the overall usability of the Distress Thermometer (DT) and symptom checklist and concordance of DT ratings between pediatric patients, their caregivers and medical providers. Eighty youth (ages 7–21) living with NF1 completed the DT and an accompanying checklist. The findings of this study suggest the DT and symptom checklist was acceptable and feasible to complete in a clinic setting. A small subset reported high distress that required further assessment and intervention. Significant discordance between distress ratings of caregivers and children and healthcare providers was also found. Overall, the DT and accompanying symptom checklist provide important information to identify the presence of distress and contextualize the child's distress but is limited by not assessing whether these symptoms interfere with the child's daily life.
Biolytic Effect of Rhamnolipid Biosurfactant and Dodecyl Sulfate Against Phagotrophic Alga Ochromonas danica
Authors: Invally Krutika , Ju Lu‐Kwang
Published: July 2017

Surfactants can affect biological activities and pose serious threats to the aquatic ecosystem if discharged without proper treatment. Rhamnolipid is a biosurfactant with promising agricultural, industrial and biomedical applications. It is important to assess the risks posed by rhamnolipid before it is adopted for large scale use. In this study, toxicity of rhamnolipid was estimated with the effects of motility loss, membrane permeability, and cell lysis using a phagotrophic alga Ochromonas danica. O. danica is a sensitive algal species without a protective cell wall and it represents a group of phagotrophic flagellates ecologically important in the aquatic ecosystem. A common synthetic surfactant, sodium dodecyl sulfate (SDS), was used for comparison. Results suggested that rhamnolipid is significantly less biolytic than SDS and the effects required longer exposure. Lysis of O. danica cells by rhamnolipid was serious only at concentrations over its critical micelle concentration. Motility loss was, however, significantly more sensitive; about 75% loss after 20 min exposure to 50 mg/L rhamnolipid.
Anti‐Inflammatory Effects of Stearidonic Acid Mediated by Suppression of NF‐κB and MAP‐Kinase Pathways in Macrophages
Authors: Sung Jeehye , Jeon Heemang , Kim In‐Hwan , Jeong Heon Sang , Lee Junsoo
Published: July 2017

Stearidonic acid (SDA, 18:4n‐3) is an omega‐3 polyunsaturated fatty acid present in oils derived from plants of the Boraginaceae family. In this study, we determined the anti‐inflammatory effects of SDA isolated from echium oil on lipopolysaccharide (LPS)‐induced inflammatory responses in RAW 264.7 macrophages. SDA significantly downregulated the levels of the inducible nitric oxide synthase (iNOS) protein, thereby suppressing the production of nitric oxide (NO) in LPS‐stimulated RAW 264.7 cells. In addition, SDA inhibited the nuclear translocation and promoter activity of nuclear factor κB (NFκB) and the phosphorylation of mitogen‐activated protein kinases (MAPK) such as extracellular signal regulated kinase 1/2, c‐jun N terminal kinase, and p38 in LPS‐stimulated RAW 264.7 cells. Our results showed that SDA exerted anti‐inflammatory effects by suppressing iNOS‐mediated NO production via inactivation of NFκB and MAPK signaling pathways.
Experiencing early life maternal separation increases pain sensitivity in adult offspring
Authors: Vilela Fabiana Cardoso , Vieira Jádina Santos , Giusti‐Paiva Alexandre , da Silva Marcelo Lourenço
Published: July 2017

Maternal separation is a widely accepted model for studying long‐term behavioral changes produced by events during early life and its association with changes in pain sensitivity. Thus, our objective was to evaluate sensitivity to pain, under different stimuli in adult male and female rats that had undergone early life maternal separation. Animals were subjected to maternal separation from postnatal day (PND) 2–15. Maternal behavior and litter weight were evaluated during this period. Sensitivity to pain was assessed in offsprings during adulthood by exposing them to stimuli, including formalin (5%; 20 μl), a hot plate, and the electronic von Frey test, 4, 7, 10, and 24 h after the administration of saline or Freund's complete adjuvant (CFA) injection. Maternal separation did not affect maternal behavior or litter weight during PND 2–15. However, experiencing maternal separation increased pain sensitivity in the rats subjected to formalin by increasing number of flinches and licking time Further, females appeared more sensitive than males to thermal stimuli, as they showed a decrease in latency in the hot plate test. In this test, male and female offsprings that were exposed to early life maternal separation and received the CFA injection also showed a reduction in latency to react to the painful stimuli. In the von Frey test, there was a reduction in withdrawal threshold in maternal separation animals injected with CFA, thus demonstrating a greater sensitivity to the mechanical stimuli. In conclusion, experiencing early life maternal separation increased pain sensitivity in adult offsprings. Thus, our data are important to understand the impact of environmental influences, such as stressful life events during critical developmental periods, on pain vulnerability.
Presymptomatic atrophy in autosomal dominant Alzheimer's disease: A serial magnetic resonance imaging study
Authors: Kinnunen Kirsi M. , Cash David M. , Poole Teresa , Frost Chris , Benzinger Tammie L.S. , Ahsan R. Laila , Leung Kelvin K. , Cardoso M. Jorge , Modat Marc , Malone Ian B. , Morris John C. , Bateman Randall J. , Marcus Daniel S. , Goate Alison , Salloway Stephen P. , Correia Stephen , Sperling Reisa A. , Chhatwal Jasmeer P. , Mayeux Richard P. , Brickman Adam M. , Martins Ralph N. , Farlow Martin R. , Ghetti Bernardino , Saykin Andrew J. , Jack Clifford R. , Schofield Peter R. , McDade Eric , Weiner Michael W. , Ringman John M. , Thompson Paul M. , Masters Colin L. , Rowe Christopher C. , Rossor Martin N. , Ourselin Sebastien , Fox Nick C. ,   Dominantly Inherited Alzheimer Network (DIAN)
Published: July 2017

Introduction

Identifying at what point atrophy rates first change in Alzheimer's disease is important for informing design of presymptomatic trials.

Methods

Serial T1‐weighted magnetic resonance imaging scans of 94 participants (28 noncarriers, 66 carriers) from the Dominantly Inherited Alzheimer Network were used to measure brain, ventricular, and hippocampal atrophy rates. For each structure, nonlinear mixed‐effects models estimated the change‐points when atrophy rates deviate from normal and the rates of change before and after this point.

Results

Atrophy increased after the change‐point, which occurred 1–1.5 years (assuming a single step change in atrophy rate) or 3–8 years (assuming gradual acceleration of atrophy) before expected symptom onset. At expected symptom onset, estimated atrophy rates were at least 3.6 times than those before the change‐point.

Discussion

Atrophy rates are pathologically increased up to seven years before “expected onset”. During this period, atrophy rates may be useful for inclusion and tracking of disease progression.
Comparison of EMG signals recorded by surface electrodes on endotracheal tube and thyroid cartilage during monitored thyroidectomy
Authors: Chiang Feng‐Yu , Lu I‐Cheng , Chang Pi‐Ying , Dionigi Gianlorenzo , Randolph Gregory W. , Sun Hui , Lee Kang‐Dae , Tae Kyung , Ji Yong Bae , Kim Sung Won , Lee Hyoung Shin , Wu Che‐Wei
Published: July 2017

A variety of electromyography (EMG) recording methods were reported during intraoperative neural monitoring (IONM) of recurrent laryngeal nerve (RLN) in thyroid surgery. This study compared two surface recording methods that were obtained by electrodes on endotracheal tube (ET) and thyroid cartilage (TC). This study analyzed 205 RLNs at risk in 110 patients undergoing monitored thyroidectomy. Each patient was intubated with an EMG ET during general anesthesia. A pair of single needle electrode was inserted obliquely into the TC lamina on each side. Standard IONM procedure was routinely followed, and EMG signals recorded by the ET and TC electrodes at each step were compared. In all nerves, evoked laryngeal EMG signals were reliably recorded by the ET and TC electrodes, and showed the same typical waveform and latency. The EMG signals recorded by the TC electrodes showed significantly higher amplitudes and stability compared to those by the ET electrodes. Both recording methods accurately detected 7 partial loss of signal (LOS) and 2 complete LOS events caused by traction stress, but only the ET electrodes falsely detected 3 LOS events caused by ET displacement during surgical manipulation. Two patients with true complete LOS experienced temporary RLN palsy postoperatively. Neither permanent RLN palsy, nor complications from ET or TC electrodes were encountered in this study. Both electrodes are effective and reliable for recording laryngeal EMG signals during monitored thyroidectomy. Compared to ET electrodes, TC electrodes obtain higher and more stable EMG signals as well as fewer false EMG results during IONM.
Blood Hemostatic Changes During an Ultraendurance Road Cycling Event in a Hot Environment
Authors: Kupchak Brian R. , Kazman Josh B. , Vingren Jakob L. , Levitt Danielle E. , Lee Elaine C. , Williamson Keith H. , Armstrong Lawrence E. , Deuster Patricia A.
Published: July 2017

Objective

This study aims to examine blood hemostatic responses to completing a 164-km road cycling event in a hot environment.

Methods

Thirty-seven subjects (28 men and 9 women; 51.8±9.5 [mean±SD] y) completed the ride in 6.6±1.1 hours. Anthropometrics (height, body mass [taken also during morning of the ride], percent body fat [%]) were collected the day before the ride. Blood samples were collected on the morning of the ride (PRE) and immediately after (IP) the subject completed the ride. Concentrations of platelet, platelet activation, coagulation, and fibrinolytic markers (platelet factor 4, β-thromboglobulin, von Willebrand factor antigen, thrombin-antithrombin complex, thrombomodulin, and D-Dimer) were measured. Associations between changes from PRE- to IP-ride were examined as a function of event completion time and subject characteristics (demographics and anthropometrics).

Results

All blood hemostatic markers increased significantly ( P < .001) from PRE to IP. After controlling for PRE values, finishing time was negatively correlated with platelet factor 4 ( r = 0.40; P = .017), while percent body fat (%BF) was negatively correlated with thrombin-antithrombin complex ( r = –0.35; P = .038) and to thrombomodulin ( r = –0.36; P = .036). In addition, male subjects had greater concentrations of thrombin-antithrombin complex (d = 0.63; P < .05) and natural logarithm thrombomodulin (d = 6.42; P < .05) than female subjects.

Conclusion

Completing the 164-km road cycling event in hot conditions resulted in increased concentrations of platelet, platelet activation, coagulation, and fibrinolytic markers in both men and women. Although platelet activation and coagulation occurred, the fibrinolytic system markers also increased, which appears to balance blood hemostasis and may prevent clot formation during exercise in a hot environment.
STUDY OF TREE-TO-TREE YIELD VARIABILITY AMONG SEEDLING-BASED CACAO POPULATIONS IN AN INDUSTRIAL PLANTATION IN CÔTE D'IVOIRE
Authors: WIBAUX THOMAS , KONAN DANY-CLAUDE , SNOECK DIDIER , JAGORET PATRICK , BASTIDE PHILIPPE
Published: July 2017

In Côte d'Ivoire, the world's largest cocoa producer, cacao (Theobroma cacaoL.) is usually grown from seed. The genetics consist of a mix of amelonado, trinitario and selected hybrids. This mix of varieties generates high phenotypic variabilities, including variability in tree productivity, within cacao populations in both smallholder and industrial plantations. Tree-to-tree variability in yield has been reported in cacao breeding trials under different environmental conditions. However, it has never been considered a limiting factor for agronomical performance of seedling-based cacao plantations. Around 10 000 cacao trees from seven plots under different environmental conditions in a cacao plantation in Côte d'Ivoire were monitored for 2 years. Pod production of individual trees was recorded and annual average tree pod yields were assessed. High heterogeneity in cacao-tree yields was observed in all plots, with coefficients of variation ranging from 56 to 102%. The distribution of cacao-tree yields in each plot was positively skewed. Analysis of these distributions showed that unproductive trees represented a significant proportion of cacao tree populations (7%), and the 20% least productive trees accounted for 3% of production. The 20% most productive trees were responsible for 46% of the total pod production of a plot. This heterogeneity reflects a major imbalance in the agronomical performances of low- and high-yielding trees and also represents possible efficiency gaps in seedling-based cacao plantations, which could be overcome through innovative corrective strategies, opening new pathways for improvement of cacao-based cropping systems.
Cumulative exposure to childhood adversity, and treated attention deficit/hyperactivity disorder: a cohort study of 543 650 adolescents and young adults in Sweden
Authors: Björkenstam E. , Björkenstam C. , Jablonska B. , Kosidou K.
Published: July 2017

Background

Though childhood adversity (CA) has been associated with the risk of attention deficit/hyperactivity disorder (ADHD), little is known about the effect of cumulative CAs and whether there are clusters of CAs that are more closely related with ADHD.

Methods

We used a Swedish cohort of 543 650 individuals born 1987–1991. Register-based CAs included familial death, substantial parental substance abuse and psychiatric disorder, substantial parental criminality, parental separation, household public assistance recipiency, and residential instability. Individuals were followed from year 2006 when they were 15–19 years of age, for treated ADHD, defined as a registered ICD diagnosis and/or prescription of medications to treat ADHD. Logistic regression analysis was used to calculate odds ratios (OR) with 95% confidence intervals (CI). Latent Class Analyses (LCA) were used to identify clusters based on the different CAs.

Results

All CAs increased the odds of ADHD in late adolescence and early adulthood; ORs ranged from 1.6 (95% CI 1.5–1.8) for familial death to 2.7 (95% CI 2.6–2.9) for household public assistance. We found a dose-response relationship between cumulative CA and ADHD; individuals with 4+ CAs had a markedly increased risk for ADHD (OR 5.5, 95% CI 5.0–6.0). LCA analyses revealed six distinct classes of CA associated with ADHD, of which ‘exposure to most adversities’ entailed highest risk.

Conclusion

CA is a strong risk factor for ADHD, particularly when accumulated. Early and efficient detection of CA is of importance for interventions targeted to improve long-term mental health outcomes among disadvantaged children.
No Big Brother Here: Heterarchy, Shona Political Succession and the Relationship between Great Zimbabwe and Khami, Southern Africa
Authors: Chirikure Shadreck , Mukwende Tawanda , Moffett Abigail J. , Nyamushosho Robert T. , Bandama Foreman , House Michelle
Published: July 2017

In southern Africa, there has been a long-standing but unsubstantiated assumption that the site of Khami evolved out of Great Zimbabwe's demise around ad 1450. The study of local ceramics from the two sites indicate that the respective ceramic traditions are clearly different across the entire sequence, pointing towards different cultural affiliations in their origins. Furthermore, there are tangible typological differences between and within their related dry-stone architecture. Finally, absolute and relative chronologies of the two sites suggest that Khami flourished as a major centre from the late fourteenth/early fifteenth century, long before Great Zimbabwe's decline. Great Zimbabwe also continued to be occupied into the late seventeenth and perhaps eighteenth centuries, after the decline of Khami. Consequently, the combined significance of these observations contradicts the parent-offspring relationship implied in traditional frameworks. Instead, as chronologically overlapping entities, the relationship between Khami and Great Zimbabwe, was heterarchical. However, within the individual polities, malleable hierarchies of control and situational heterarchies were a common feature. This is in tune with historically documented political relations in related pre-colonial southern Zambezian states, and motivates for contextual approaches to imagining power relations in pre-colonial African contexts.