bluuebunny/crossref_metadata_2025 huggingface dataset:
Simplified Luminal Water Imaging for the Detection of Prostate Cancer From Multiecho T2 MR Images
Authors: Devine William , Giganti Francesco , Johnston Edward W. , Sidhu Harbir S. , Panagiotaki Eleftheria , Punwani Shonit , Alexander Daniel C. , Atkinson David
Published: December 2018

Background

Luminal water imaging (LWI) suffers less from imaging artifacts than the diffusion‐weighted imaging used in multiparametric MRI of the prostate. LWI obtains multicompartment tissue information from a multiecho T2 dataset.

Purpose

To compare a simplified LWI technique with apparent diffusion coefficient (ADC) in classifying lesions based on groupings of PI‐RADS v2 scores. Secondary aims were to investigate whether LWI differentiates between histologically confirmed tumor and normal tissue as effectively as ADC, and whether LWI is correlated with the multicompartment parameters of the vascular, extracellular, and restricted diffusion for cytometry in tumors (VERDICT) diffusion model.

Study Type

A subset of a larger prospective study.

Population

In all, 65 male patients aged 49–79 were scanned.

Field Strength/Sequence

A 32‐echo T2 and a six b‐value diffusion sequence (0, 90, 500, 1500, 2000, 3000 s/mm2) at 3T.

Assessment

Regions of interest were placed by a board‐certified radiologist in areas of lesion and benign tissue and given PI‐RADS v2 scores.

Statistical Tests

Receiver operating characteristic and logistic regression analyses were performed.

Results

LWI classifies tissue as PI‐RADS 1,2 or PI‐RADS 3,4,5 with an area under curve (AUC) value of 0.779, compared with 0.764 for ADC. LWI differentiated histologically confirmed malignant from nonmalignant tissue with AUC, sensitivity, and specificity values of 0.81, 75%, and 87%, compared with 0.75, 83%, and 67% for ADC. The microstructural basis of the LWI technique is further suggested by the correspondence with the VERDICT diffusion‐based microstructural imaging technique, with α, A1, A2, and LWF showing significant correlations.

Data Conclusion

LWI alone can predict PI‐RADS v2 score groupings and detect histologically confirmed tumors with an ability similar to ADC alone without the limitations of diffusion‐weighted MRI. This is important, given that ADC has an advantage in these tests as it already informs PI‐RADS v2 scoring. LWI also provides multicompartment information that has an explicit biophysical interpretation, unlike ADC.

Level of Evidence: 3

Technical Efficacy: Stage 2

J. Magn. Reson. Imaging 2019;50:910–917.
Compressed sensing for solving electromagnetic scattering problems of complex wire structures over a wide range of incident angle
Authors: Hu Jin‐Hua , Chen Ming‐Sheng , Huang Zhi‐Xiang , Zhang Liang , Wu Xian‐Liang , Cao Xin‐Yuan , Ma Xue‐Hua
Published: December 2018

An efficient scheme is proposed and implemented for studying electromagnetic scattering problems of complex wire structures over a wide range of incident angle. A set of linear vector basis functions is applied to discretize the complex structures. Moreover, a novel approach based on the compressed sensing (CS) technique is presented and used to form several new excitation sources, which include various spatial information to obtain several measurements. With the help of proper sparse representation, the real induced currents of any incident angles can be calculated by using the orthogonal matching pursuit technique (OMP). To demonstrate the efficiency and the accuracy of the proposed method, numerical simulations of a pair of Yagi‐Uda antenna, a pair of spiral antenna, and a pair of spiral antenna array are accomplished by the new scheme, and the radiation pattern and Radar Cross Section (RCS) of the antennas are accurately calculated.
Stability condition of the dispersive HIE‐FDTD method for the simulation of graphene
Authors: Xu Ning , Chen Juan , Wang Jianguo
Published: December 2018

This paper derives exactly the stability condition of the dispersive hybrid implicit‐explicit finite‐difference time‐domain (HIE‐FDTD) method used for the simulations of the graphene‐based devices. Combining with the Routh‐Hurwitz criterion, an analytical closed‐form stability expression is obtained. The result shows that the maximum time increment of the dispersive HIE‐FDTD method is only associated with two spatial discretizations instead of the smallest one inside the graphene layer. Numerical example validates this stability condition.
Enhanced oxidative stress and the treatment by edaravone in mice model of amyotrophic lateral sclerosis
Authors: Ohta Yasuyuki , Nomura Emi , Shang Jingwei , Feng Tian , Huang Yong , Liu Xia , Shi Xiaowen , Nakano Yumiko , Hishikawa Nozomi , Sato Kota , Takemoto Mami , Yamashita Toru , Abe Koji
Published: December 2018

Oxidative stress is associated with the degeneration of both motor neurons and skeletal muscles in amyotrophic lateral sclerosis (ALS). A free radical scavenger edaravone has been proven as a therapeutic drug for ALS patients, but the neuroprotective mechanism for the oxidative stress of ALS has not been fully investigated. In this study, we investigated oxidative stress in ALS model mice bearing both oxidative stress sensor nuclear erythroid 2‐related factor 2 (Nrf2) and G93A‐human Cu/Zn superoxide dismutase (Nrf2/G93A) treated by edaravone. In vivo Nrf2 imaging analysis showed the accelerated oxidative stress both in spinal motor neurons and lower limb muscles of Nrf2/G93A mice according to disease progression in addition to the enhancement of serum oxidative stress marker dROMS. These were significantly alleviated by edaravone treatment accompanied by clinical improvements (rotarod test). The present study suggests that in vivo optical imaging of Nrf2 is useful for detecting oxidative stress in ALS, and edaravone alleviates the degeneration of both motor neurons and muscles related to oxidative stress in ALS patients.
Removal of a Hickman catheter using a laser sheath
Authors: Le Kien Vo , Okamura Hideo , Homma Takehiro , Ohgo Takeshi , Noda Takashi , Kusano Kengo
Published: December 2018

A 31‐year‐old female with 10 years indwelled Hickman catheter for idiopathic pulmonary hypertension presented infectious findings. We decided to remove it but simple traction did not work. Although it was an off labeled use, we could remove it using a laser sheath and snare technique without any complication.
Ripening season affects tissue mineral concentration and nutrient partitioning in peach trees
Authors: Zhou Qi , Melgar Juan Carlos
Published: December 2018

The objective of this research was to determine the influence of ripening season on nutrient concentration and nutrient partitioning of peach trees (Prunus persica L. Batsch). We selected peach trees from three different ripening seasons and measured: (1) the concentration of macronutrients in pruned wood, thinned fruitlets, harvested fruit, and leaves fallen in autumn and (2) the total amount of macronutrients at each of these removal events. Our results showed that early‐season cultivars had more K in pruned wood, more P and K in fallen leaves, and more N, P, K, and Mg in mature fruits than mid‐ and late‐season cultivars. Also, early‐season cultivars removed more dry weight from pruned wood and fallen leaves but less from fruit than mid‐ and late‐season cultivars. These results suggest that different ripening season can affect peach tree nutrient concentration and nutrient partitioning and, consequently, peach cultivars harvested at different times of the year may benefit from specific fertilization programs rather than uniform, calendar‐based fertilization programs.
A vacuum ultraviolet photoionization time‐of‐flight mass spectrometer with high sensitivity for study of gas‐phase radical reaction in a flow tube
Authors: Wen Zuoying , Tang Xiaofeng , Wang Chengcheng , Fittschen Christa , Wang Tao , Zhang Cuihong , Yang Jiuzhong , Pan Yang , Liu Fuyi , Zhang Weijun
Published: December 2018

Photoionization mass spectrometry as a powerful analytical method has been widely utilized and provided valuable insight in the field of gas‐phase reactions. Here, a highly sensitive vacuum ultraviolet (VUV) photoionization time‐of‐flight mass spectrometer combined with a microwave discharge generator and a fast flow tube reactor has been developed to study radical reactions of atmospheric and combustion interests. Two kinds of continuous light sources, the tunable VUV synchrotron radiation at Hefei, China for isomer‐specific product detection and a commercial krypton discharge lamp for time‐consuming kinetic measurements, are employed as photoionization sources in the apparatus. A multiplexed detection with high sensitivity (the limit of detection ∼0.8 ppb) and high mass resolution (M/ΔM ∼ 2100) has been approached. As representative examples, the self‐reaction of the methyl radical, CH3, and the reaction of the methyl radical with molecular oxygen are studied and multiple species including reactive radicals and isomeric/isobaric products are detected and identified. In addition, some preliminary results related to the reaction kinetics are also presented.
Olfactory function in mild cognitive impairment and Alzheimer's disease: A meta‐analysis
Authors: Jung Hahn Jin , Shin In‐Soo , Lee Ji‐Eun
Published: December 2018

Objective

Olfactory function is altered in mild cognitive impairment (MCI) and Alzheimer's disease (AD); therefore, it may serve as a useful tool for the early detection of MCI before its advancement to AD. The aim of this meta‐analysis was to investigate olfactory deficits in patients with MCI and AD.

Study Design

Literature search.

Methods

A search was conducted of the electronic databases PubMed, Embase, and Web of Science from their inception until 2017. We included original articles with adequate data on the identification, threshold, and/or discrimination of olfactory function in MCI or AD. The standard mean difference and 95% confidence interval (CI) were calculated. The studies were weighted according to inverse variance estimates. The effect sizes were categorized as small [Cohen's d = 0.2], medium (d = 0.5), or large (d ≥ 0.8) based on these methods. Subgroup analyses were performed based on mean age and sex differences between the groups.

Results

Twelve articles (reporting 21 effects) examining 563 patients with MCI and 788 patients with AD, were included in the meta‐analysis. Compared to MCI, AD had moderate to large heterogeneous effects on olfactory function (Cohen's d = 0.64, 95% CI: 0.50, 0.78). Olfactory identification tests demonstrated larger effects (d = 0.71, 95% CI: 0.51, 0.91) than did tests of other olfactory domains.

Conclusions

Meta‐analysis results revealed that olfactory identification was more profoundly impaired in patients with AD than in those with MCI. These findings suggest that a simple test of odor identification is valuable in differentiating individuals at a risk of AD.

Level of Evidence

NA Laryngoscope, 129:362–369, 2019
Synthetic, Chemically Defined Polymer‐Coated Microcarriers for the Expansion of Human Mesenchymal Stem Cells
Authors: Krutty John D. , Dias Andrew D. , Yun Junsu , Murphy William L. , Gopalan Padma
Published: December 2018

Mesenchymal stem cells (MSC), also called marrow stromal cells, are adult cells that have attracted interest for their potential uses in therapeutic applications. There is a pressing need for scalable culture systems due to the large number of cells needed for clinical treatments. Here, a tailorable thin polymer coating—poly(poly(ethylene glycol) methyl ether methacrylate‐ran‐vinyl dimethyl azlactone‐ran‐glycidyl methacrylate) [P(PEGMEMA‐r‐VDM‐r‐GMA); PVG]—to the surface of commercially available polystyrene and glass microcarriers to create chemically defined surfaces for large‐scale cell expansion is applied. These chemically defined microcarriers create a reproducible surface that does not rely on the adsorption of xenogenic serum proteins to mediate cell adhesion. Specifically, this coating method anchors PVG copolymer through ring opening nucleophilic attack by amine residues on poly‐l‐lysine that is pre‐adsorbed to the surface of microcarriers. Importantly, this anchoring reaction preserves the monomer VDM reactivity for subsequent functionalization with an integrin‐specific Arg‐Gly‐Asp peptide to enable cell adhesion and expansion via a one‐step reaction in aqueous media. MSCs cultured on PVG‐coated microcarriers achieve sixfold expansion—similar to the expansion achieved on PS microcarriers—and retain their ability to differentiate after harvesting.
Dynamic, Bioresponsive Hydrogels via Changes in DNA Aptamer Conformation
Authors: Bae Se Won , Lee Jae Sung , Harms Victoria M. , Murphy William L.
Published: December 2018

DNA aptamers are integrated into synthetic hydrogel networks with the aim of creating hydrogels that undergo volume changes when exposed to target molecules. Specifically, single‐stranded DNA aptamers in cDNA‐bound, extended state are incorporated into hydrogel networks as cross‐links, so that the nanoscale conformational change of DNA aptamers upon binding to target molecules will induce macroscopic volume decreases of hydrogels. Hydrogels incorporating adenosine triphosphate (ATP)–binding aptamers undergo controllable volume decreases of up to 40.3 ± 4.6% when exposed to ATP, depending on the concentration of DNA aptamers incorporated in the hydrogel network, temperature, and target molecule concentration. Importantly, this approach can be generalized to aptamer sequences with distinct binding targets, as demonstrated here that hydrogels incorporating an insulin‐binding aptamer undergo volume changes in response to soluble insulin. This work provides an example of bioinspired hydrogels that undergo macroscopic volume changes that stem from conformational shifts in resident DNA‐based cross‐links.
Enhanced Thermo‐Mechanical Stiffness, Thermal Stability, and Fire Retardant Performance of Surface‐Modified 2D MoS2Nanosheet‐Reinforced Polyurethane Composites
Authors: Malkappa Kuruma , Ray Suprakas Sinha , Kumar Neeraj
Published: December 2018

This article reports new‐generation 2D‐MoS2nanosheet‐containing polyurethane (PU) composite materials with improved thermo‐mechanical stiffness, thermal stability, and fire retardation properties. The surface of 2D‐MoS2nanosheets is modified with melamine (M‐MoS2), and then PU composites with varying M‐MoS2loadings are synthesized using an in situ polymerization method. During polymerization, 3‐amino‐propyl‐trimethoxy silane is introduced to create silicate functionality on the PU chains, which further improves the compatibility between PU and M‐MoS2. Microscopy studies confirm the distribution of highly intercalated and agglomerated M‐MoS2nanosheets in the PU matrix. The PU composite containing 5 wt% M‐MoS2shows a 65% higher storage modulus (at 30 °C) than that of pure PU. The thermal stability of pure PU is significantly improved (62 °C) after composite formation. Thermogravimetric analysis in combination with FTIR spectroscopy shows that the PU/M‐MoS2composites release less toxic gases during thermal degradation compared to pure PU. Moreover, the composite containing 5 wt% M‐MoS2shows improved fire retardation properties, with 45% and 67.5% decrease in the peak heat and total heat release rates, respectively, as compared with those of pure PU. In summary, 2D‐MoS2is shown to have potential as an advanced nano‐filler to obtain stiffer PU composite with improved fire retardant property for structural application.
Fiber Formation from Silk Fibroin Using Pressurized Gyration
Authors: Heseltine Phoebe Louiseanne , Hosken Joseph , Agboh Chris , Farrar David , Homer‐Vanniasinkam Shervanthi , Edirisinghe Mohan
Published: December 2018

Silk has attracted considerable interest for use in biomedical applications due to its high strength and promising biocompatibility. Degummed silk, consisting only of silk fibroin (SF), has been processed using various methods and can be made into films, sponges, and fibers. Pressurized gyration (PG) is capable of rapidly producing aligned fibers and offers a great amount of control over their structure and morphology. Here, SF fibers are produced for the first time using PG. The effect of varying SF concentration and applied working pressure to the gyration vessel is reported, along with the resulting effect on fiber diameter, morphology, and structural composition. Aligned microfibers are found at concentrations of 8, 10, 12 w/v%, with the lowest fiber diameters reported at 8 w/v% SF 0.3 MPa applied pressure (2.1 ± 1.3 µm). Fourier‐transform infrared spectroscopy (FTIR) confirms the existence of PG spun fibers in both random coil and β‐sheet formations.
Synthesis and Characterization of Castor Oil‐Based Polyurethane Nanocomposites
Authors: Wong Kai Yi , Gan Seng Neon , Teh Geok Bee , Sin Sau Leng
Published: December 2018

A series of castor oil‐based polyurethane (PU) with and without the incorporation of Halloysite nanoclay as filler are synthesized via addition polymerization of polycaprolactone‐diol (PCL) and methylene diphenyl diisocyante (MDI) as monomers. The PUs are characterized by using attenuated total reflectance‐Fourier transform infrared spectroscopy (ATR‐FTIR), thermogravimetric anaysis (TGA), differential scanning calorimetry (DSC), scanning electron microscope (SEM), and pencil hardness test. The TGA thermogram showed that the incorporation of castor oil affected the thermal stability of the PU matrices by 7–9% in reduction of the decomposition temperature; whereas the incorporation of Halloysite nanoclay into the PU matrices increased the thermal stability by 3–5% in the detection of higher decomposition temperature. The DSC thermograms of the castor‐oil based PU and castor oil‐based PU with Halloysite nanoclay showed reduction in glass transition temperature (Tg) by 13–33 and 8–14 °C, respectively as compared to pristine PU and castor‐oil based PU. It is envisaged that the reduction in Tg is caused by the non‐uniformity of dispersion of the Halloysite nanoclay throughout the PU matrices and hence, affected the mobility of the PU chains. The SEM images further confirmed the non‐uniformity of dispersion of the Halloysite nanoclay in the PU films. Pencil hardness test indicated that the PU films coated on glass slides had lower than 1H hardness.
Hard Carbon Films Synthesized By Atmospheric Pressure Filamentary Dielectric Barrier Discharge
Authors: Suzuki Tetsuya , Shirakura Akira
Published: December 2018

To synthesize hydrogenated amorphous carbon (a‐C:H) films, filamentary dielectric discharge (FDBD) is used to improve their mechanical properties compared to the films synthesized by glow dielectric barrier discharge (GDBD), which is generally used for atmospheric pressure‐plasma‐enhanced chemical vapor deposition. The discharge form transitioned from GDBD to FDBD when the gap between the electrodes is increased from 1 to 4 mm. The hardness of the films increased from 3.7 to 11.9 GPa by using FDBD. The results indicate that hard a‐C:H films can be synthesized at room temperature by atmospheric pressure using FDBD.
Citric Acid Cross‐Linking of Carboxymethyl Sago Starch Based Hydrogel for Controlled Release Application
Authors: Nordin Nurul Aida , Rahman Norizah Abdul , Talip Norhashidah , Yacob Norzita
Published: December 2018

Carboxymethyl sago starch (CMSS) is prepared using carboxymethylation reaction. The reaction times are varied to determine the optimum degree of substitution (DS) and reaction efficiency (RE). The CMSS prepared via carboxymethylation for 3 h shows the highest DS and RE. The CMSS hydrogel is prepared using citric acid as a cross‐linker. The effects of the preparation condition of citric acid/CMSS hydrogel such as the percentage of citric acid (w/w), cross‐linking periods, and cross‐linking temperature on the gel fraction are investigated. The optimization of preparation conditions of hydrogels using cross‐linker demonstrated 25% higher gel fraction compared to previously reported sago starch hydrogels prepared via irradiation cross‐linking. The swelling study is carried out in distilled water (pH 6.5), acidic (pH 1.2), neutral (pH 7.4), and alkaline (pH 11) media. The release behavior of methylene blue (MB) as the drug model suggests the potential of CMSS hydrogel to be used in drug delivery applications.
Self Assembly in Functionalized Butadiene Based Polyurethanes
Authors: Kunduru Konda Reddy , Rao Billa Narasimha , Jana Tushar
Published: December 2018

Chemical modification of hydroxyl terminated polybutadiene (HTPB) oligomer without altering its inherent properties is achieved by covalently attaching various functional moieties such as 2, 4‐dinitrophenyl (DNB) and triazine derivatives to the terminal carbons of HTPB. Fibrous self‐assembly network formed by the hydrogen bonding through DNB groups is found to be the driving force for the unprecedented simultaneous improvement in both tensile strength and elongation in case of HTPB‐DNB based polyurethane (PU). For example, tensile strength and elongation at break of the PU obtained using isophorone diisocyanate are found to be 1.21 MPa and 570.26%, respectively in case of HTPB‐DNB whereas these values are 0.36 MPa and 91.22%, respectively in case of HTPB. In contrary, non hydrogen bonding supramolecular assembly of hard segment domains in triazine functionalized HTPB‐PU resulted in reinforcement of mechanical strength and aggregation induced emission.
Fluorescent PEG‐PLA Copolymers Synthesized from Ugi Four Component Condensation
Authors: von der Weid Joana S. , Icart Luis P. , Dias Marcos L.
Published: December 2018

This work describes the synthesis of fluorescent poly(acid lactic) (PLA)‐polyethylene glycol (PEG) block copolymers by using the Ugi multicomponent reaction (MCR). Specific aldehyde end‐functionalized PLA (PLA‐COH) and carboxylic acid end functionalized PEG (PEG‐COOH) with different molecular weights were synthesized to be used in the MCR with fluorescein containing amino groups. Different fluorescent diblock copolymers of PEG‐PLA conjugated with fluorescein were synthesized, giving yields up to 75%. Identification of PLA, PEG and fluorescein present in the copolymer's structure was confirmed by spectroscopic methods (1H‐NMR, FTIR and UV spectroscopy) and molecular weight determined by GPC. Thus, this work proposes an application of Ugi MCR in the preparation of an interesting biomasked PLA‐based fluorescent copolymer for application as drug delivery systems.
Effect of Titanium Dioxide on Adhesion and Conductivity Behavior of Polyaniline/Alkyd Composite for Solar Cell Application
Authors: Phang Sook Wai , Ramli Mariam Fadzlina , Khong Choy Hung , Lim Wen Huei , Gan Seng Neon
Published: December 2018

This study attempts to improve the adhesion and conductivity of polyaniline (PAni) by incorporating an alkyd and titanium dioxide (TiO2), respectively. PAni with different TiO2 content (10, 20, and 40%) are synthesized through chemical oxidation method by using aniline (Ani) monomer, dioctyl sodium sulfosuccinate (AOT) dopant, and ammonium persulphate (APS) oxidant at 0 °C for 24 h. In order to improve the adhesion of PAni‐TiO2 on fluoride doped‐tin oxide (FTO) glass prior to its application as counter electrode (CE) in Dye‐Sensitized Solar Cell (DSSC), a palm oil‐based alkyd is added into PAni‐TiO2 composite. Chemical structures of PAni‐TiO2/Alkyd are confirmed by Fourier transform infrared spectrophotometer (FTIR) and ultraviolet‐visible (UV‐Vis) spectrophotometry analyses. Conductivity measurement is determined by using four point probe method and adhesion test is performed following ASTM D3599. Results showed that conductivity of PAni had significantly improved from 3.53 × 10−3 (without TiO2) to 8.16 × 10−3–6.59 × 10−2 S cm−1 (with TiO2). However, the conductivity of all PAni‐TiO2/Alkyd samples on FTO glass showed high conductivity (6.11–6.32 × 102 S cm−1) and better adhesion behavior on FTO glass except for the sample with 40% of TiO2. The plausible mechanisms between PAni‐TiO2/Alkyd and FTO glass are proposed in this study based on the FTIR and UV‐Vis analyses.
Thermal Properties and Morphology of Poly(ethylene oxide)/Poly(n‐butyl methacrylate) Blends
Authors: Ramli Hairunnisa , Chan Chin H. , Ali Ab M. M.
Published: December 2018

From the thermodynamic point of view, most of the high molar‐mass binary polymer blends are immiscible due to the entropic contribution to the free energy of mixing is relatively small. The miscibility of the systems on the molecular scale can be assessed by the thermal properties such as quantities of glass transition temperature (Tg) and change in heat capacity (ΔCp) of the polymers. For a semi‐crystalline polymer such as poly(ethylene oxide) (PEO), the crystallinity (X*) and the melting temperature (Tm) can also give some hints on the miscibility. Apart from the thermal properties, additional scientific findings such as morphology of the blends are needed as supplementary evidences to support the results. We focus on the PEO as the polymer host, blends with poly(n‐butyl methacrylate) (PnBMA) which were prepared using solution casting technique. Thermal properties of PEO/PnBMA polymer blends were investigated by modulated differential scanning calorimeter (MDSC) on the isothermal crystallized samples at 25 °C. Tg of PEO in the blends do not show significant variation with addition of PnBMA for entire composition range while for Tg of PnBMA in the blends, it is challenging to be estimated under the experimental condition due to the overlapping of the Tg of PnBMA and melting endotherm of PEO. Constancy of quantity Tg of PEO and ΔCp of PEO corresponding to the content of PEO in the blends suggest that PEO and PnBMA are immiscible for entire blend composition. X* and Tm of PEO in the blends show insignificant variation in PEO/PnBMA blends, when PEO as major component. This implies that these blends are immiscible under the experimental conditions as agreed with results of Tg and ΔCp. Spherulitic morphologies of PEO in the blends were studied by polarized optical microscopy (POM). PnBMA phase disperses randomly in PEO matrix when PEO in excess. The absence of significant change for the fibrillar spherulitic structures of PEO spherulites with addition of PnBMA (when PEO is the major component) suggests that immiscibility of PEO and PnBMA. Besides, the crystalline structure of PEO in PEO/PnBMA blends using X‐ray diffraction (XRD) reveals that the crystalline structure of PEO is not disturbed with the addition of PnBMA when PEO is in excess as the two distinct peaks of PEO do not shift as compared to neat PEO. Impedance spectroscopy (IS) studies show that the ionic conductivities (σDC) of the polymer blends at room temperature slightly increase with increasing of PEO with the order of magnitude of 10−11–10−10 S cm−1. This system serves as a potential polymer host as solid polymer electrolytes when added with inorganic salt.
Batch‐to‐Batch Reproducibility Studies of Pilot‐Scale Emulsion Polymerization of Poly(styrene‐co‐butyl acrylate)
Authors: Harmain Hazwan , Chan Chin Han
Published: December 2018

Studies on emulsion polymerization (EP) of poly(styrene‐co‐butyl acrylate) [P(S‐co‐BA)] can be accessed in open literature. However, these studies are mostly focusing on lab‐scale polymerization and subsequently characterization, of which discussion on pilot‐scale or mass‐production‐scale of the polymerization is scant. This paper focuses on the batch‐to‐batch reproducibility of P(S‐co‐BA) with 78.7 mol% of styrene and 21.3 mol% of butyl acrylate via EP in 3 metric‐ton (MT) pilot‐scale reactor. Polymerization efficiency, molecular, and physical characterization of the copolymers are examined using gravimetric analysis. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), thermal gravimetry analysis (TGA), differential scanning calorimeter (DSC), viscometer, capillary rheometer, particle size analyzer (including dynamic light scattering and laser diffraction techniques), and scanning electron microscope (SEM). The gravimetric analysis on the monomer conversion reveals that the polymerization in 3‐MT reactor is efficient with 100% conversion. Besides, 1H‐NMR results reveal that the styrene‐to‐butyl acrylate mole ratio of the copolymer is of close approximation of the monomer feed amount while FTIR is a rather convenient quality control (QC) tool for batch‐to‐batch reproducibility on the copolymer molecular structured. The physical characteristic of [P(S‐co‐BA)] for all five batches are considered reproducible.
Dosage‐dependent effects of monensin on the rumen microbiota of lactating dairy cattle
Authors: McGarvey Jeffery A. , Place Sara , Palumbo Jeffrey , Hnasko Robert , Mitloehner Frank
Published: December 2018

We examined the dose‐dependent effects of feeding lactating dairy cows a standard diet supplemented with monensin at 175, 368, or 518 mg cow‐1 day‐1on the rumen microbiota. For each dosage, 3 animals were randomly assigned into groups and fed the same basal total mixed ration diet supplemented with monensin, at the respective dose. After 20 days, rumen samples were taken and the effect on the microbiota was examined by 16S rRNA gene sequence analysis and qPCR. At the lowest dose no significant change in 16S rRNA gene sequences associated with any bacterial phyla was observed; however, at the medium and high dosages, we observed significant reductions in sequences associated with gram‐positive bacteria and significant increases in those associated with gram‐negative bacteria that were dosage dependent. All dosages reduced the levels of sequences associated with methanogenic archaea in the rumen, with the medium dosage showing the largest decline. No significant difference was observed for the 18S rRNA gene sequences associated with protozoa in any of the libraries. Our results indicate that with this diet the medium dosage of monensin was most efficacious for the reduction in methanogenic archaea in the rumen of lactating dairy.
Insertional translocation involving an additional nonchromothriptic chromosome in constitutional chromothripsis: Rule or exception?
Authors: Kurtas Nehir Edibe , Xumerle Luciano , Giussani Ursula , Pansa Alessandra , Cardarelli Laura , Bertini Veronica , Valetto Angelo , Liehr Thomas , Clara Bonaglia Maria , Errichiello Edoardo , Delledonne Massimo , Zuffardi Orsetta
Published: December 2018

Background

Chromothripsis, which is the local massive shattering of one or more chromosomes and their reassembly in a disordered array with frequent loss of some fragments, has been mainly reported in association with abnormal phenotypes. We report three unrelated healthy persons, two of which parenting a child with some degree of intellectual disability, carrying a chromothripsis involving respectively one, two, and three chromosomes, which was detected only after whole‐genome sequencing. Unexpectedly, in all three cases a fragment from one of the chromothripsed chromosomes resulted to be inserted within a nonchromothripsed one.

Methods

Conventional cytogenetic techniques, paired‐end whole‐genome sequencing, polymerase chain reaction, and Sanger sequencing were used to characterize complex rearrangements, copy‐number variations, and breakpoint sequences in all three families.

Results

In two families, one parent was carrier of a balanced chromothripsis causing in the index case a deletion and a noncontiguous duplication at 3q in case 1, and a t(6;14) translocation associated with interstitial 14q deletion in case 2. In the third family, an unbalanced chromothripsis involving chromosomes 6, 7, and 15 was inherited to the proband by the mosaic parent. In all three parents, the chromothripsis was concurrent with an insertional translocation of a portion of one of the chromothriptic chromosomes within a further chromosome that was not involved in the chromothripsis event.

Conclusion

Our findings show that (a) both simple and complex unbalanced rearrangements may result by the recombination of a cryptic parental balanced chromothripsis and that (b) insertional translocations are the spy of more complex rearrangements and not simply a three‐breakpoint event.
Blow‐up behavior of the Solution for the problem in a subdiffusive mediums
Authors: Liu Hon Hung Terence
Published: December 2018

The diffusion problem in a subdiffusive medium is formulated by using the fractional differential operator. In this paper, we consider a fractional differential equation with concentrated source. The existence of the solution in a finite time is given. The finite time blow‐up criteria for the solution of the problem is established, and the location of the blow‐up point is investigated.
A high gain 60 GHz antipodal Fermi‐tapered slot antenna based on robust synthesized dielectric
Authors: Loo Xi Sung , Win Moe Z. , Yeo Kiat Seng
Published: December 2018

A high performance antipodal Fermi taper slot antenna based on unique synthesized dielectric is presented for ultra‐wideband radar applications at 60 GHz band. Specifically, the synthesized dielectric is implemented based on machined holes concentrates only at aperture area to improve its mechanical robustness for lengthy antenna. Further, it is able to suppress back lobe level by 2.5 dB through curving tapered end of the antenna. Concurrently, sine corrugations and dielectric loading are adopted to improve radiation pattern and gain of the antenna for over 20 dB.
Is the dose‐averaged LET a reliable predictor for the relative biological effectiveness?
Authors: Grün Rebecca , Friedrich Thomas , Traneus Erik , Scholz Michael
Published: December 2018

Purpose

The dose‐averaged linear energy transfer (LETD) is frequently used as representative quantity for the biological effectiveness of a radiation field. Moreover, relative biological effectiveness (RBE) values measured or calculated in mixed radiation fields are typically plotted vs the LETD. In this study, we will investigate whether the LETD is an appropriate quantity to describe the RBE of any mixed radiation field of protons and heavier ions and discuss potential limitations.

Methods

To study the reliability of LETD, we investigate model predictions of RBE in monoenergetic beams under track segment conditions and pristine Bragg peaks as well as spread out Bragg peaks (SOBP) in water. Both, the pristine Bragg peaks and the SOBPs are regarded as mixed radiation fields in this analysis, that is, they are characterized by a certain width of the energy spectrum of the projectile, although the underlying energy distribution is much broader in the case of an SOBP as compared to a pristine peak. For both cases, the corresponding RBE values are compared to those of strictly monoenergetic particles under track segment conditions, characterized by a single LET value. For the planning we use the treatment planning software TRiP98 together with the Local Effect Model to predict the RBE of protons, helium, and carbon ions. We further compare our model predictions for protons with a simplistic linear RBE‐LET relationship representative for the phenomenological models in literature.

Results

Regarding pristine Bragg peaks in water, the deviations in RBE compared to monoenergetic particles under track segment conditions for the same LET value are low (mostly 0–5%), except for the distal fall‐off region. The situation changes in SOBPs for which we found deviations in the order of up to 25% for the lighter particles and even more pronounced deviations for heavier particles like carbon ions.

Conclusions

The analysis showed that LETD is a sufficiently accurate predictor for RBE only in regions with comparably narrow, but not in regions with broad, LET distribution as in a single SOBP or in multiple overlapping fields. The deviations are caused by the nonlinearity of the RBE(LET) relationship in the case of track segment conditions. Thus, independent of the underlying RBE model and the particle type regarded, as long as the RBE(LET) relationship deviates from being purely linear, LETD is not a good predictor for RBE, and especially for heavier particles like carbon ions knowledge of the underlying LET distribution is mandatory to describe the RBE in mixed radiation fields.
Fast high‐resolution brain metabolite mapping on a clinical 3T MRI by accelerated H‐FID‐MRSI and low‐rank constrained reconstruction
Authors: Klauser Antoine , Courvoisier Sebastien , Kasten Jeffrey , Kocher Michel , Guerquin‐Kern Matthieu , Van De Ville Dimitri , Lazeyras Francois
Published: December 2018

Purpose

Epitomizing the advantages of ultra short echo time and no chemical shift displacement error, high‐resolution‐free induction decay magnetic resonance spectroscopic imaging (FID‐MRSI) sequences have proven to be highly effective in providing unbiased characterizations of metabolite distributions. However, its merits are often overshadowed in high‐resolution settings by reduced signal‐to‐noise ratios resulting from the smaller voxel volumes procured by extensive phase encoding and the related acquisition times.

Methods

To address these limitations, we here propose an acquisition and reconstruction scheme that offers both implicit dataset denoising and acquisition acceleration. Specifically, a slice selective high‐resolution FID‐MRSI sequence was implemented. Spectroscopic datasets were processed to remove fat contamination, and then reconstructed using a total generalized variation (TGV) regularized low‐rank model. We further measured reconstruction performance for random undersampled data to assess feasibility of a compressed‐sensing SENSE acceleration scheme. Performance of the lipid suppression was assessed using an ad hoc phantom, while that of the low‐rank TGV reconstruction model was benchmarked using simulated MRSI data. To assess real‐world performance, 2D FID‐MRSI acquisitions of the brain in healthy volunteers were reconstructed using the proposed framework.

Results

Results from the phantom and simulated data demonstrate that skull lipid contamination is effectively removed and that data reconstruction quality is improved with the low‐rank TGV model. Also, we demonstrated that the presented acquisition and reconstruction methods are compatible with a compressed‐sensing SENSE acceleration scheme.

Conclusions

An original reconstruction pipeline for 2D H‐FID‐MRSI datasets was presented that places high‐resolution metabolite mapping on 3T MR scanners within clinically feasible limits.
Non‐contrast myocardial infarct scar assessment using a hybrid native T1 and magnetization transfer imaging sequence at 1.5T
Authors: Duan Chong , Zhu Yanjie , Jang Jihye , Rodriguez Jennifer , Neisius Ulf , Fahmy Ahmed S. , Nezafat Reza
Published: December 2018

Purpose

To develop a gadolinium‐free cardiac MR technique that simultaneously exploits native T1 and magnetization transfer (MT) contrast for the imaging of myocardial infarction.

Methods

A novel hybrid T one and magnetization transfer (HYTOM) method was developed based on the modified look‐locker inversion recovery (MOLLI) sequence, with a train of MT‐prep pulses placed before the balanced SSFP (bSSFP) readout pulses. Numerical simulations, based on Bloch‐McConnell equations, were performed to investigate the effects of MT induced by (1) the bSSFP readout pulses, and (2) the MT‐prep pulses, on the measured, “apparent,” native T1 values. The HYTOM method was then tested on 8 healthy adult subjects, 6 patients, and a swine with prior myocardial infarction (MI). The resulting imaging contrast between normal myocardium and infarcted tissues was compared with that of MOLLI. Late gadolinium enhancement (LGE) images were also obtained for infarct assessment in patients and swine.

Results

Numerical simulation and in vivo studies in healthy volunteers demonstrated that MT effects, resulting from on‐resonance bSSFP excitation pulses and off‐resonance MT‐prep pulses, reduce the measured T1 in both MOLLI and HTYOM. In vivo studies in patients and swine showed that the HYTOM sequence can identify locations of MI, as seen on LGE. Furthermore, the HYTOM method yields higher myocardium‐to‐scar contrast than MOLLI (contrast‐to‐noise ratio: 7.33 ± 1.67 vs. 3.77 ± 0.66, P < 0.01).

Conclusion

The proposed HYTOM method simultaneously exploits native T1 and MT contrast and significantly boosts the imaging contrast for myocardial infarction.
Internal erosion in dike‐on‐foundation modeled by a coupled hydromechanical approach
Authors: Yang Jie , Yin Zhen‐Yu , Laouafa Farid , Hicher Pierre‐Yves
Published: December 2018

One of the major causes of instability in geotechnical structures such as dikes or earth dams is internal erosion, an insidious process that occurs over a long period of time. Research on this topic is still fairly new and much more needs to be understood in order to solve the problems posed by this phenomenon. This paper proposes a hydromechanical model based on porous continuous medium theory to assess how internal erosion impacts the safety of earthen structures. The saturated soil is considered as a mixture of four interacting constituents: soil skeleton, erodible fines, fluidized fine particles, and fluid. The detachment and transport of the fine particles are described by a mass exchange model between the solid and the fluid phases. An elastoplastic constitutive model for sand‐silt mixtures has been developed to monitor the effect of the evolution of both porosity and fines content induced by internal erosion upon the behavior of the soil skeleton. The model has been numerically solved with the finite element method. It has then been applied to the specific case study of a dike foundation subjected to internal erosion induced by the presence of a karstic cavity beneath the alluvium layer. The numerical results show the onset of erosion, the time‐space evolution of the eroded zone, and the hydromechanical response of the soil constituting the dike, all of which highlights the effects of the cavity location, the erosion rate, and the fines content.
Percutaneous Endoscopic Gastrostomy Tubes May Be Associated With Preservation of Lung Function in Patients With Cystic Fibrosis
Authors: Khalaf Racha T. , Green Deanna , Amankwah Ernest K. , Peck Jacquelin , Carr Vanessa , Goldenberg Neil A. , Wilsey Michael
Published: December 2018

Background

Improving nutrition status of patients with cystic fibrosis (CF) has a positive effect on pulmonary function.

Methods

We conducted a retrospective case‐control study evaluating the effect of percutaneous endoscopic gastrostomy (PEG) placement on body mass index (BMI) and forced expiratory volume in 1 second percent predicted (FEV1) between matched subjects with CF who received PEG (n = 20) and controls who did not (n = 40).

Results

We observed that after adjusting for mutation class and baseline BMI, BMI percentile increased per month for those with PEG (0.51, 95% confidence interval (CI) = −0.05–1.08, P = .08), but decreased for those without PEG (−0.03, 95% CI = −0.33–0.28, P = .86); however, the difference (0.54; 95% CI = −0.10–1.18, P = .10) was not statistically significant. FEV1 change with time showed a decrease for patients with PEG (−0.04; 95% CI = −0.30–0.22, P = .74) and those without PEG (−.22; 95% CI = −0.45–0.01, P = .06). Although the decrease for those without PEG was higher than those with PEG, the difference between the groups was not statistically significant (0.18; 95% CI = −0.17–0.52, P = .32)

Conclusion

Lung function trajectory showed a trend towards preservation among patients with CF who receive PEG despite lack of significant difference in BMI. There may be a favorable effect of PEG on lung function independent of changes in BMI.
Lower knowledge about diabetes among foreign‐born compared to Swedish‐born persons with diabetes—A descriptive study
Authors: Pettersson Sara , Hadziabdic Emina , Marklund Helén , Hjelm Katarina
Published: December 2018

Aim

To compare foreign‐ and Swedish‐born persons, diagnosed with type 2 diabetes, to study whether there are dissimilarities in knowledge about diabetes and to study determinants of knowledge.

Design

A cross‐sectional descriptive study was conducted.

Method

Data were collected between September 2014 and March 2016, using the standardized Diabetes Knowledge Test (DKT), statistically analysed.

Results

The results showed dissimilarities in knowledge between foreign‐ and Swedish‐born persons, supporting the hypothesis that foreign‐born persons had lower knowledge about diabetes than Swedish‐born persons. There was a relationship between poor knowledge and country of birth, marital status and employment status. Country of birth was the strongest independent determinant of knowledge about diabetes. The risk of poor knowledge was ten times higher among persons born in the Middle East or in another country outside Europe compared with Swedish‐born persons. Other influencing factors for poor knowledge about diabetes were being not gainfully employed and living alone.
Isothermal crystallization kinetics of biodegradable poly(lactic acid)/poly(ε‐caprolactone) blends compatibilized with low‐molecular weight block copolymers
Authors: Pereira Fabiana Massarente , Canevarolo Sebastião Vicente , Chinelatto Marcelo Aparecido
Published: December 2018

The isothermal crystallization kinetics of biodegradable blends made of poly(lactic acid) (PLA) and poly(ε‐caprolactone) (PCL) compatibilized with two different low molecular weight block copolymers, that is, ε‐caprolactone/tetramethylene ether glycol and ε‐caprolactone/aliphatic polycarbonate (CB), was done. Blends were prepared by melt mixing in an extruder, while isothermal crystallization kinetics and morphologies were investigated by thermal (differential scanning calorimetry) and thermo‐optical (quantitative polarized light optical microscopy [qPLOM]) quantitative methods. Data were analyzed using the Avrami equation, revealing 2D and 3D growth and simultaneous heterogeneous nucleation. The presence of low molecular weight compatibilizers, that is, 2,000 g mol−1, accelerated the PLA crystallization rate by two to threefold when compared with neat PLA, with high degrees of crystallinity (40–43%) as confirmed by PLOM images. The activation energy (Ea) showed that PCL inhibits PLA crystallization; however, the addition of block copolymers used as compatibilizers of the blends reduced Ea values, increasing the chain mobility of PLA and thus increasing the crystallization rate. POLYM. ENG. SCI., 59:E161–E169, 2019. © 2018 Society of Plastics Engineers