bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of updating the MALDI‐TOF MS database on the identification of nontuberculous mycobacteria
Authors: Rodriguez‐Temporal D. , Perez‐Risco D. , Struzka E. A. , Mas M. , Alcaide F.
Published: May 2017

Conventional identification of mycobacteria species is slow, laborious and has low discriminatory power. Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) has proved highly effective for identifying conventional bacteria, and it may also be useful for identifying mycobacteria. The aim of this study was to evaluate and compare MALDI‐TOF MS with currently recommended molecular methods for the identification of nontuberculous mycobacteria (NTM), applying Mycobacteria Libraries v3.0 (ML3.0) and v2.0 (ML2.0). A total of 240 clinical isolates of 41 NTM species grown on solid media were analysed: 132 isolates of slow‐growing mycobacteria and 108 of rapid‐growing mycobacteria. MALDI‐TOF MS, using ML3.0, identified 192 (80%) NTM isolates with a score ≥1.7, encompassing 35 (85.4%) different species, that is, 17 (7.1%; p = 0.0863) isolates and 15 (36.6%; p = 0.0339) species more than currently recommended molecular techniques (polymerase chain reaction reverse hybridization). All these isolates were correctly identified according to molecular identification methods. The application of ML3.0 also identified 15 (6.2%) NTM isolates more than ML2.0 (p < 0.01). The scores obtained with MALDI‐TOF MS using ML3.0 (mean score: 1.960) were higher in 147 (61.2%) isolates than when using ML2.0 (mean score: 1.797; p < 0.01). Three of the species analysed were not included in either database, so they were not recognized by this system. In conclusion, MALDI‐TOF MS identified more isolates and species than the recommended polymerase chain reaction reverse hybridization assays. Although the new ML3.0 is not the definitive database, it yielded better results than ML2.0. This shows that the updating of the MALDI‐TOF MS database plays an essential role in mycobacterial identification. Copyright © 2017 John Wiley & Sons, Ltd.
Controlling the structure of sequence‐defined poly(phosphodiester)s for optimal MS/MS reading of digital information
Authors: Amalian J.‐A. , Al Ouahabi A. , Cavallo G. , König N. F. , Poyer S. , Lutz J.‐F. , Charles L.
Published: May 2017

Digital polymers are monodisperse chains with a controlled sequence of co‐monomers, defined as letters of an alphabet, and are used to store information at the molecular level. Reading such messages is hence a sequencing task that can be efficiently achieved by tandem mass spectrometry. To improve their readability, structure of sequence‐controlled synthetic polymers can be optimized, based on considerations regarding their fragmentation behavior. This strategy is described here for poly(phosphodiester)s, which were synthesized as monodisperse chains with more than 100 units but exhibited extremely complex dissociation spectra. In these polymers, two repeating units that differ by a simple H/CH3 variation were defined as the 0 and 1 bit of the ASCII code and spaced by a phosphate moiety. They were readily ionized in negative ion mode electrospray but dissociated via cleavage at all phosphate bonds upon collisional activation. Although allowing a complete sequence coverage of digital poly(phosphodiester)s, this fragmentation behavior was not efficient for macromolecules with more than 50 co‐monomers, and data interpretation was very tedious. The structure of these polymers was then modified by introducing alkoxyamine linkages at appropriate location throughout the chain. A first design consisted of placing these low dissociation energy bonds between each monomeric bit: while cleavage of this sole bond greatly simplified MS/MS spectra, efficient sequencing was limited to chains with up to about 50 units. In contrast, introduction of alkoxyamine bonds between each byte (i.e. a set of eight co‐monomers) was a more successful strategy. Long messages (so far, up to 8 bytes) could be read in MS3 experiments, where single‐byte containing fragments released during the first activation stage were further dissociated for sequencing. The whole sequence of such byte‐truncated poly(phosphodiester)s could be easily re‐constructed based on a mass tagging system which permits to determine the original location of each byte in the chain. Copyright © 2017 John Wiley & Sons, Ltd.
Human papillomavirus type 16 E6 oncoprotein promotes proliferation and invasion of non‐small cell lung cancer cells through Toll‐like receptor 3 signaling pathway
Authors: Wang Xia , Zhang Zhiqiang , Cao Huimin , Niu Wenyi , Li Mingying , Xi Xiu'e , Wang Jing
Published: May 2017

Human papillomavirus (HPV) oncoproteins play vital roles in non‐small cell lung cancer (NSCLC) pathogenesis, and Toll‐like receptors (TLRs) contribute to tumor progression. However, interaction between HPV oncoproteins and TLR signaling in NSCLC progression remains unclear. Thus, the aim of the study was to explore effects of HPV16 E6 oncoprotein‐induced TLRs pathway on growth and invasion of NSCLC cells and to examine potential mechanisms being involved. Recombinant plasmid (pcDNA‐HPV16 E6) expressing HPV16 E6 protein was constructed. The expression prolife of TLRs was measured in NSCLC cell line A549 with or without pcDNA‐HPV16 E6 transfection by real‐time reverse polymerase chain reaction and Western blot. Cellular proliferation, invasion, cytokine productions, and downstream signaling pathways were also examined in TLR3‐silencing/pcDNA‐HPV16 E6 transfect A549 cells. Overexpression of HPV16 E6 increased proliferation, invasion, proliferation cytokine secretion, and TLR3 expression of A549 cells, while TLR3 silence inhibited HPV16 E6‐induced tumor bioactivities of A549 cells. Down‐regulation of TLR3 suppressed HPV16 E6‐induced phosphorylation of Src, but did not affect TRIF expression. Moreover, inhibition of Src pathway also suppressed proliferation and invasion of A549 cells. In conclusion, HPV16 E6 oncoprotein promoted the bioactivities of NSCLC cells. TLR3‐Src signaling pathway might be involved in this procession by up‐regulation of cytokine production. The interaction between HPV16 E6 protein and TLR3 might contribute to the poor prognosis of NSCLC.
Comorbidities and medications of patients with chronic hepatitis C under specialist care in the UK
Authors: Hudson Benjamin , Walker Alex J. , Irving William L.
Published: May 2017

Designing services with the capacity and expertise to meet the needs of the chronic hepatitis C (CHC) population in the era of direct acting antivirals (DAAs), and widening access to such treatments, requires detailed understanding of the characteristics and healthcare needs of the existing patient population. In this retrospective analysis of data from the National HCV Research UK Biobank between March 2012 and October 2014, the characteristics of the CHC population currently under specialist care in the UK were evaluated—with specific focus upon use of medications, adverse lifestyle choices, and comorbidities. Demographic data, risk factors for CHC acquisition, HCV genotype, liver disease status, lifestyle factors, comorbidities, and medication classes were collected. Data were analyzed by history of injecting drug use (IDU), age, and severity of liver disease. A total of 6278 patients (70.5% white; median age, 52 years) from 59 UK specialist centres were included; 59.1% of patients had acquired HCV through IDU. The prevalence of adverse lifestyle factors was significantly lower in non‐IDU compared with previous IDU or recent IDU patients. Depression was common in the previous (50.8%) and recent IDU (68.1%) groups, compared with 27.6% in non‐IDU patients. Cirrhosis was common (23.6%), and prevalence increased with age. We describe a heterogeneous, polymorbid, and aging population of CHC patients in secondary care, and demonstrate underrepresentation of injecting drug users within the current system. The implications of this present significant challenges to physicians and healthcare commissioners in designing services which are fit for purpose inthe DAA era.
Down regulation of TRIF, TLR3, and MAVS in HCV infected liver correlates with the outcome of infection
Authors: Kar Premashis , Kumar Deepak , Gumma Phani Kumar , Chowdhury Soumya Jyoti , Karra Vijay Kumar
Published: May 2017

In virus‐infected cells, pattern recognition receptors (PRRs) recruits their specific adaptor molecules, mitochondrial antiviral signaling protein (MAVS), TIR‐domain‐containing adapter‐inducing interferon‐β (TRIF), and TNF receptor associated factor (TRAF6) which induces interferon. Toll‐like receptor 3 (TLR3) induces activation of the NF‐kappa B (NF‐κB) for interferon production. The study has been designed to assess the correlation of TLR3, MAVS, TRIF, and TRAF6 outcome of HCV infection. The 46 chronic hepatitis C (CHC) patients were screened for LFT (Liver function test), HBsAg, Anti HCV, viral load, histology, and expression of TLR3, MAVS, TRIF, and TRAF6 genes. Out of 46 CHC patients, 7 were on therapy. The 12 healthy controls were screened for LFT, HBsAg, Anti HCV and gene expressions. The gene expressions were studied in liver tissue and measured using semi‐quantitative analysis of Western blots. It has been observed that the expression of TRAF6 was independent of HCV infection. The expression of TRIF, TLR3, and MAVS were significantly (P < 0.05) down regulated in CHC (N = 46) compared to healthy controls (N = 12), in high viral load (N = 21) compared to low viral load (N = 25), in HAI (Histology activity index) 1‐4 (N = 12), 5‐8 (N = 16), 9‐12 (N = 8), 13‐18 (N = 5) compared to HAI 0 (N = 5) cases. The significant reduction in the expression of TRIF, TLR3, and MAVS was observed in non‐responder (N = 3) compared to responder (N = 4) after treatment (P < 0.05). The HCV viral load was positively correlated with the disease severity. The down regulation of TRIF, TLR3, and MAVS expressions in CHC correlates with the disease severity and the outcome of HCV infection.
Exogenous progesterone is neuroprotective following injury to the male zebra finch brain
Authors: Blackshear Katherine , Giessner Stephanie , Hayden John P. , Duncan Kelli A.
Published: May 2017

The use of progesterone following brain injury has a controversial history. On one hand, some lab‐based models have showed progesterone as being neuroprotective, but on the other, clinical trials have showed quite the opposite. One of many complaints that arose from this discrepancy was the lack of a diverse pool of animal models and paradigms employed during the preclinical phase. However, over the past decade, the zebra finch has emerged as an optimal organism for the study of steroid‐mediated neuroprotection. Following an injury, steroid hormones and receptors are upregulated, serving to decrease neuroinflammation and overall damage to the brain. As compared to other vertebrate models, zebra finches can upregulate expression of both estrogens and androgens at a faster and more robust response, suggesting that vertebrates differ in their neuroprotective mechanisms and timing following injury. Therefore, to expand the types organisms studied in pre‐clinical trials, we chose to use zebra finches. While the majority of work in the zebra finch brain has focused on estrogens and androgens, we sought to clarify the role of progesterone following injury. Adult male zebra finches were given daily injections of progesterone following a penetrating injury and then were assessed for the size of injury and expression of various genes associated with neuroinflammation and cell survival. Treatment with progesterone decreased the injury size in zebra finches over controls and increased expression of various genes associated with cell survival and neuroinflammation. These data suggest that progesterone does mediate neuroprotection, most likely through the alteration of neuroinflammatory and cell survival pathways.
Seasonal and intraseasonal variability of precipitable water vapour in the Chajnantor plateau, Chile
Authors: Marín Julio C. , Barrett Bradford S.
Published: May 2017

The Chajnantor plateau is located in the Atacama Desert at over 4800 m above sea level. The plateau features a large fraction of days during the year where dry and stable atmospheric conditions predominate. The suitability of the type of astronomy observations routinely made at sites across the Chajnantor region at different times of the year depends on the variability of atmospheric water vapour.

In this work, we study seasonal and intraseasonal variability associated with periods of large and low precipitable water vapour (PWV) in the Chajnantor region over 32 years. We establish large‐scale conditions favourable for above‐ and below‐normal PWV for each of the four seasons. We also explore whether intraseasonal PWV variations are related to the Madden–Julian Oscillation (MJO). Below‐normal PWV in winter, spring, and autumn seasons was found associated with mostly zonal 500‐hPa winds, which advect drier than normal air from the anticyclone over the eastern portions of the southeast (SE) Pacific Ocean. In summer, periods with below‐normal PWV were found to have anomalously south‐westerly winds at mid‐levels, also indicating transport of anomalously dry air from the stable SE Pacific. In winter, spring, and autumn seasons, above‐normal PWV was generally associated with north‐westerly mid‐tropospheric wind anomalies, indicating advection of above‐normal PWV from the subtropical and tropical regions of the SE Pacific Ocean. Above‐normal PWV conditions in summer were associated with nearly calm winds at 500 hPa. Months and phases of the MJO for the most extreme anomalies of PWV for each season agreed well with the seasonal anomalies. Furthermore, three independent reanalysis data sets generally agreed on MJO phases associated with largest positive and negative PWV anomalies. This agreement provides evidence for the first time that the MJO modulates the PWV content over the Atacama Desert.
Linking trends in urban extreme rainfall to urban flooding in China
Authors: Zhou Xinyao , Bai Zhijie , Yang Yonghui
Published: May 2017

Storm‐induced urban flooding is a global issue that causes large damages and fatalities. Characterizing extreme rainfall is critical to urban flood risk management. Although China's cities have been experiencing a rapid increase in urban flooding in recent decades, there is a lack of national‐wide analysis of the occurrence of extreme urban rainfall. This study examined the trends in extreme rainfall in 146 cities in China for the period 1960–2014. The trends were also analysed in terms of city size (small, big and mega cities) in two city clusters (Jing‐Jin‐Jin City Cluster and Yangtze City Cluster). There was a strong spatial variation in the trends of extreme rainfall across the country, with negative trends in North China and positive trends in Southeast China. Both positive and negative trends were noted for the other regions of China. All the cities in Jing‐Jin‐Ji City Cluster had a decreasing trend in extreme rainfall, with a significant decline (p = 0.03) for mega cities. Then all cities in the Yangtze City Cluster had an increasing trend in extreme rainfall, with a significant increase (p=0.02) for big cities. The findings suggested that efforts to alleviate storm‐induced urban flash floods should take into account both spatial disparities in climate and future changes in extreme rainfall events.
Cultivation of Solanum tuberosum in a former mining district for a safe human consumption integrating simulated digestion
Authors: Sierra María José , López‐Nicolás Rubén , González‐Bermúdez Carlos A , Frontela‐Saseta Carmen , Millán Rocio
Published: May 2017

BACKGROUND

Potato (Solanum tuberosum) is a global crop and by far the most important non‐cereal crop in the world. Therefore, it is necessary to assure its safe consumption. This is especially relevant in the case of its cultivation in abandoned mining areas, where the population tends to return to agriculture. In the present work, the objective is to evaluate the contribution to the diet of nutrients and contaminants of potato grown in soils from the Almadén area (mining district) by studying the intestinal absorption (in vitro) of the tuber, taking into account the preparation methods for its consumption.

RESULTS

The results of contaminant and nutrient contents show that the potato peel retains significantly more elements (mainly in the case of toxic elements) than the flesh. Furthermore, potato (peel and flesh) is a good source of iron.

CONCLUSION

It is recommended to boil potatoes with the peel in order to minimize nutrient loss and, before consumption, peeling them to eliminate possible risks due to contaminants. In addition, to minimize the risk due of mercury and to improve the levels of calcium, magnesium, potassium and sodium, it is recommended to add salt during the boiling process. © 2017 Society of Chemical Industry
Cardamom supplementation improves inflammatory and oxidative stress biomarkers in hyperlipidemic, overweight, and obese pre‐diabetic women: a randomized double‐blind clinical trial
Authors: Kazemi Shiva , Yaghooblou Fatemeh , Siassi Fereydoun , Rahimi Foroushani Abbas , Ghavipour Mahsa , Koohdani Fariba , Sotoudeh Gity
Published: May 2017

BACKGROUND

Several preclinical studies have shown that spices may decrease the risk of chronic diseases. However, it has been suggested that more clinical trials be carried out to strengthen this preclinical evidence. The purpose of the present study was to evaluate the effects of cardamom (Elettaria cardamomum) supplementation on inflammation and oxidative stress in hyperlipidemic, overweight, and obese pre‐diabetic women.

METHODS

This randomized, placebo‐controlled, double‐blind clinical trial was conducted on 80 pre‐diabetic subjects. They randomly received the cardamom supplement (n = 40, 3 g d−1) or identical inert placebo (n = 40) for 8 weeks. Serum concentrations of high‐sensitivity C‐reactive protein (hs‐CRP), interleukin‐6 (IL‐6), tumour necrosis factor α, total antioxidant capacity, malondialdehyde (MDA), protein carbonyl, and erythrocyte superoxide dismutase and glutathione reductase activity were analyzed at the baseline and after intervention.

RESULTS

After the adjustment of some covariates, cardamom supplementation significantly decreased serum hs‐CRP (P = 0.02), hs‐CRP:IL‐6 ratio (P = 0.008), and MDA (P = 0.009) compared with the placebo group.

CONCLUSION

Cardamom could improve some parameters of inflammation and oxidative stress in pre‐diabetic subjects. Thus it may be useful in reducing complications associated with inflammation and oxidative stress in these patients. Copyright © 2017 Society of Chemical Industry © 2017 Society of Chemical Industry
Faba beans and peas in poultry feed: economic assessment
Authors: Proskina Liga , Cerina Sallija
Published: May 2017

BACKGROUND

Broiler diets mainly consist of cereals and protein‐rich feed sources; in the EU‐27, poultry farming consumes 24% of the total amount of protein‐rich feedstuffs. Since the EU produces only 30% of the total quantity of protein crops used for feed, it is necessary to promote the use of traditional European protein crops (beans, peas) for feed in livestock farming. The research aim is to identify economic gains from the production of broiler chicken meat, replacing soybean meal with domestic faba beans and field peas in broiler chicken diets.

RESULTS

Adding field peas and faba beans to the broiler feed ration resulted in a significant live weight increase (5.74–11.95%) at the selling age, a decrease in the feed conversion ratio by 0.61–6.06%, and decrease in the product unit cost (15.34–37.06%) as well as an increase in the production efficiency factor (8.70–48.54), compared with the control group.

CONCLUSION

The optimum kind of legume species used in the broiler diet was peas, which were added in the amount of 200 g kg−1, resulting in live weight gain, a decrease in the feed conversion ratio and an increase in the production efficiency factor. © 2017 Society of Chemical Industry
Models to improve the non‐destructive analysis of persimmon fruit properties by VIS/NIR spectrometry
Authors: Altieri Giuseppe , Genovese Francesco , Tauriello Antonella , Di Renzo Giovanni Carlo
Published: May 2017

BACKGROUND

Visible–near‐infrared spectrometry is a technique suitable for assessing chemical and physiological properties of fruit. Some models of calibration/prediction have been tested in order to assess the feasibility of a visible–near‐infrared sensor in order to monitor persimmon fruit colour, firmness, soluble solids, titratable acidity and soluble tannins.

RESULTS

Five regression models were investigated: principal component, partial least squares, stepwise, support vector machines and ensembles of trees. These models were assessed by a 10‐fold cross‐validation with a new strategy for both outlier removal and wavelength reduction; furthermore, their statistical significance was evaluated by 100 Monte Carlo simulation runs. Principal component regression allowed us to build excellent and/or very good fit/prediction models. The results (in terms of RPD as standard deviation to performance standard error ratio) are: 9.23 (±0.26) for colour index, 10.18 (±0.37) for firmness, 7.15 (±0.28) for soluble solids content, 7.87 (±0.31) for titratable acidity and 8.91 (±0.33) for soluble tannins content.

CONCLUSION

The proposed strategy, for outlier removal and wavelength reduction, allowed the achievement of useful results. Principal component regression fit/prediction capability produced excellent results. Conversely, partial least squares regression showed fair/poor results and the remaining tested models performed badly on real data. © 2017 Society of Chemical Industry
Preparation and evaluation of a novel bonded imidazolium ionic liquid as stationary phase for gas chromatography
Authors: Dai Jia‐Ling , Zhao Li‐Hua , Shi Jie‐Hua
Published: May 2017

1‐Butyl‐3‐[(3‐trimethoxysilyl)propyl]imidazolium chloride ionic liquid was synthesized and chemically modified onto the inner wall of a fused capillary column as a stationary phase for gas chromatography. The 1‐butyl‐3‐[(3‐trimethoxysilyl)propyl]imidazolium chloride ionic liquid bonded capillary column was evaluated in detail. The results revealed that the ionic liquid bonded capillary column exhibited high column efficiency of 1.08 × 104 plates/m, and good chromatographic separation selectivity (α) for polar and non‐polar substances, and a good thermal stability between room temperature and 400°C. Moreover, the determination of thermodynamic parameters and the linear solvation energy relationship were further carried out. The results indicated that the chromatographic retention of each probe molecule on the ionic liquid bonded stationary phase was an enthalpy‐driven process, and the system constants of the linear solvation energy relationship signified that the dispersion interaction, the hydrogen bonding acidity and hydrogen bonding basicity were dominant interactions between probes and stationary phase among five interactions during the chromatographic separation. However, the contribution of each specific interaction for the stationary phase is ranked as the dispersion interaction > the hydrogen bonding basicity > the hydrogen bonding acidity.
Total detection of Tianma Toutong tablets for quality consistency by a five‐wavelength fusion fingerprint and chemometrics
Authors: Yang Zhe , Sun Guo‐xiang
Published: May 2017

A fingerprint method was developed and combined with chemometrics for quality evaluation of Tianma Toutong tablets, which are herbal medicine tablets used to treat migraine. Samples were analyzed by high‐performance liquid chromatography, where five single‐wavelength profiles (203, 232, 254, 280 and 310 nm) were fused to generate a five‐wavelength fusion fingerprint and were also used for the quantitative analysis of seven chemical markers (gastrodin, caffeic acid, hesperidin, isoimperatorin, chlorogenic acid, ferulic acid and imperatorin). A systematic quantitative fingerprint method and principal component analysis were used to analyze the generated data. Samples could be well distinguished from different manufacturers by analyzing the chromatographic data sets. In addition, the partial least squares model can serve as an antioxidant activity evaluation of Tianma Toutong tablets, as well as a reference for the selection of active constituents to analyze the spectrum–activity relationship. In summary, the integrated use of the fingerprint and chemometric analysis provides a reliable method for the identification of markers and the quality control of Tianma Toutong tablets.
Effects of iron limitation on silicon uptake kinetics and elemental stoichiometry in two Southern Ocean diatoms, Eucampia antarctica and Proboscia inermis, and the temperate diatom Thalassiosira pseudonana
Authors: Meyerink Scott W. , Ellwood Michael J. , Maher William A. , Dean Price G. , Strzepek Robert F.
Published: May 2017

We investigated the effects of iron (Fe) limitation on the elemental stoichiometry, silicic acid (Si(OH)4) uptake kinetics and cell morphology in two Southern Ocean diatoms Eucampia antarctica and Proboscia inermis and the temperate diatom Thalassiosira pseudonana. An increase in Fe‐stress resulted in reductions in specific growth rate and decreases in cellular nitrogen (N) and carbon (C) content relative to cellular biogenic silica (BSi) in both Southern Ocean diatoms and a reduction in growth rate only for T. pseudonana. Both E. antarctica and P. inermis exhibited an increase in cell volume in response to Fe‐limitation resulting in a decrease in the cell surface to volume ratio, while normalization of BSi content to cell surface area suggests these diatoms do not become more heavily silicified under Fe limitation. Kinetic Si(OH)4 uptake experiments performed on all three diatom species show that Si(OH)4 uptake is reduced under Fe‐limited conditions. For Southern Ocean diatoms, this was manifested through a decrease in the maximum specific uptake rate of Si(OH)4 (VSi‐max), along with a decrease in the half‐saturation constant for Si(OH)4 uptake (KSi) under Fe stress for E. antarctica. Our data also show that when normalized to cell surface area, VSi‐max of the three diatoms species exhibited a linear relationship with cellular growth rate, and was independent of cell morphological variations. Our results suggest that the morphological adaptations of Southern Ocean diatoms in response to Fe‐stress have the potential to affect phytoplankton community dynamics and Si(OH)4 : NO3 uptake and export ratios in Southern Ocean waters.
Mechanistic Aspects of Aqueous Heterogeneous Radical Polymerization of Styrene under Compressed CO2
Authors: Hadzir Noor Hadzuin Nik , Dong Siming , Kuchel Rhiannon P. , Lucien Frank P. , Zetterlund Per B.
Published: May 2017

Radical polymerization of styrene in aqueous emulsions pressurized by CO2 has been investigated with a view to development of low energy miniemulsion polymerization. The general requirement of high energy mixing to generate miniemulsions comprising sub‐micrometer‐size monomer droplets has long been an impediment to wide‐spread industrial application. It is demonstrated by use of online dynamic light scattering and visual observation that CO2 pressurization to the so‐called transparency pressure of an emulsion comprising styrene/hexadecane/Dowfax 8390 (anionic surfactant)/water leads to a decrease in droplet size as well as an increase in emulsion stability. However, mechanistic investigations of radical polymerization under CO2 pressure reveal that these polymerizations do not proceed as true miniemulsion polymerization systems (i.e., via exclusive monomer droplet nucleation), but are also characterized by a significant contribution of particle formation via secondary nucleation as in an ab initio emulsion polymerization.

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Electrospun Bead‐On‐String Hierarchical Fibers for Fog Harvesting Application
Authors: Thakur Neha , Ranganath Anupama Sargur , Agarwal Komal , Baji Avinash
Published: May 2017

Quest for efficient fog harvesting methods has drawn immense attention in recent times. In this study, electrospinning is used to fabricate three different sets of membranes that are based on pristine poly(N‐isopropylacrylamide) (PNIPAM) fibers, pristine polyvinylidene fluoride (PVDF) fibers, and PNIPAM‐PVDF bead‐on‐string fibers. The wettability of these membranes is investigated as a function of temperature and the effect of their wettability on the fog collection efficiency is determined. Membranes based on pristine PNIPAM and pristine PVDF fibers are fabricated using conventional electrospinning and are shown to have a smooth surface morphology. On the other hand, PNIPAM‐PVDF bead‐on‐string fibers are fabricated using core–shell electrospinning. Water collection efficiency of the membranes is compared to investigate the influence of microstructures and wettability gradient on fog harvesting ability of the samples. Among the three samples, the bead‐on‐string hierarchical fibrous membrane demonstrates the highest fog harvesting rate of 1150 ± 28 mg cm−2 h−1 at 25 °C and 909 ± 31 mg cm−2 h−1 at 40 °C. Furthermore, the results demonstrate that the presence of microstructures on the nanofibers improve the fog harvesting efficiency of PNIPAM‐PVDF bead‐on‐string fibers.

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Swelling and Tensile Properties of Tetra‐Polyethylene glycol via Coarse‐Grained Molecular Models
Authors: Wang Endian , Escobedo Fernando
Published: May 2017

Coarse‐grained (CG) implicit‐solvent potentials are developed for tetra‐polyethylene glycol (PEG) at different water concentrations using the iterative Boltzmann inversion (IBI) technique. The resulting potentials are used to study the swelling and tensile properties of tetra‐PEG gels at various swelling degrees φm. Two types of network topologies are considered, one “ideal” with a defect‐free diamond connectivity and the other “realistic” as simulated from an experimentally based cross‐linking process. Equilibrium swelling results for the realistic Tetra‐PEG networks are consistent with available experimental data, while those for the ideal tetra‐PEG networks exhibit much larger swelling. The realistic networks have higher Young's modulus Em at the same φm than ideal networks due to the presence of trapped entanglements. Uniaxial deformation results of realistic networks show that Em increases with degree of swelling, in accord with experimental results. The Young's moduli of gels at different φm confirm that the CG potentials developed by IBI are most suited to predict swelling states commensurate with the φm values at which the potentials were calibrated. A more generic, coarser potential, based on matching the persistence length of atomistic PEG chains in water, is able to produce a similar swelling behavior of an ideal diamond network.

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Preservation of chromosomal integrity in murine spermatozoa derived from gonocytes and spermatogonial stem cells surviving prenatal and postnatal exposure to γ‐rays in mice
Authors: Watanabe Hiroyuki , Kohda Atsushi , Komura Jun‐ichiro , Tateno Hiroyuki
Published: May 2017

Pre‐ and postnatal male mice were acutely (659–690 mGy/min) and continuously (0.303 mGy/min) exposed to 2 Gy γ‐rays to evaluate spermatogenic potential and chromosome damage in their germ cells as adults. Acute irradiation on Days 15.5, 16.5, and 17.5 post‐coitus affected testicular development, as a result of massive quiescent gonocyte loss; the majority of the seminiferous tubules in these testes were devoid of germ cells. Acute irradiation on Days 18.5 and 19.5 post‐coitus had less effect on testicular development and spermatogenesis, even though germ cells were quiescent gonocytes on these days. Adverse effects on testicular development and spermatogenesis were observed following continuous irradiation between Days 14.5 and 19.5 post‐coitus. Exposure to acute and continuous postnatal irradiation after the differentiation of spermatogonial stem cells and spermatogonia resulted in nearly all of the seminiferous tubules exhibiting spermatogenesis. Neither acute nor continuous irradiation was responsible for the increased number of multivalent chromosomes in primary‐spermatocyte descendents of the exposed gonocytes. In contrast, a significant increase in cells with multivalent chromosomes was observed following acute irradiation on Days 4 and 11 post‐partum. No significant increases in unstable structural chromosomal aberrations or aneuploidy in spermatozoa were observed, regardless of cell stage at irradiation or the radiation dose‐rate. Thus, murine germ cells that survive prenatal and postnatal irradiation can restore spermatogenesis and produce viable spermatozoa without chromosome damage. These findings may provide a better understanding of reproductive potential following accidental, environmental, or therapeutic irradiation during the prenatal and postnatal periods in humans.
A single‐shot T2 mapping protocol based on echo‐split gradient‐spin‐echo acquisition and parametric multiplexed sensitivity encoding based on projection onto convex sets reconstruction
Authors: Chu Mei‐Lan , Chang Hing‐Chiu , Oshio Koichi , Chen Nan‐kuei
Published: May 2017

Purpose

To develop a high‐speed T2 mapping protocol that is capable of accurately measuring T2 relaxation time constants from a single‐shot acquisition.

Theory

A new echo‐split single‐shot gradient‐spin‐echo (GRASE) pulse sequence is developed to acquire multicontrast data while suppressing signals from most nonprimary echo pathways in Carr‐Purcell‐Meiboom‐Gill (CPMG) echoes. Residual nonprimary pathway signals are taken into consideration when performing T2 mapping using a parametric multiplexed sensitivity encoding based on projection onto convex sets (parametric‐POCSMUSE) reconstruction method that incorporates extended phase graph modeling of GRASE signals.

Methods

The single‐shot echo‐split GRASE‐based T2 mapping procedure was evaluated in human studies at 3 Tesla. The acquired data were compared with reference data obtained with a more time‐consuming interleaved spin‐echo echo planar imaging protocol. T2 maps derived from conventional single‐shot GRASE scans, in which nonprimary echo pathways were not appropriately addressed, were also evaluated.

Results

Using the developed single‐shot T2 mapping protocol, quantitatively accurate T2 maps can be obtained with a short scan time (<0.2 seconds per slice).

Conclusion

Accurate T2 mapping with minimal signal contamination from CPMG high‐order echo pathways can be achieved by the developed method that integrates single‐shot echo‐split GRASE acquisition and parametric‐POCSMUSE reconstruction. Magn Reson Med 79:383–393, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Comparison of perfusion signal acquired by arterial spin labeling–prepared intravoxel incoherent motion (IVIM) MRI and conventional IVIM MRI to unravel the origin of the IVIM signal
Authors: Zhang Xingxing , Ingo Carson , Teeuwisse Wouter M. , Chen Zhensen , van Osch Matthias J. P.
Published: May 2017

Purpose

Applications of intravoxel incoherent motion (IVIM) imaging in the brain are scarce, whereas it has been successfully applied in other organs with promising results. To better understand the cerebral IVIM signal, the diffusion properties of the arterial blood flow within different parts of the cerebral vascular tree (i.e., different generations of the branching pattern) were isolated and measured by employing an arterial spin labeling (ASL) preparation module before an IVIM readout.

Methods

ASL preparation was achieved by T1‐adjusted time‐encoded pseudo‐continuous ASL (te‐pCASL). The IVIM readout module was achieved by introducing bipolar gradients immediately after the excitation pulse. The results of ASL‐IVIM were compared with those of conventional IVIM to improve our understanding of the signal generation process of IVIM.

Results

The pseudo‐diffusion coefficient D* as calculated from ASL‐IVIM data was found to decrease exponentially for postlabeling delays (PLDs) between 883 ms and 2176 ms, becoming relatively stable for PLDs longer than 2176 ms. The fast compartment of the conventional IVIM‐experiment shows comparable apparent diffusion values to the ASL signal with PLDs between 1747 ms and 2176 ms. At the longest PLDs, the observed D* values (4.0 ± 2.8 × 10−3 mm2/s) are approximately 4.5 times higher than the slow compartment (0.90 ± 0.05 × 10−3 mm2/s) of the conventional IVIM experiment.

Conclusion

This study showed much more complicated diffusion properties of vascular signal than the conventionally assumed single D* of the perfusion compartment in the two‐compartment model of IVIM (biexponential behavior). Magn Reson Med 79:723–729, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
A one‐step biomarker quantification methodology for DCE‐MRI of adnexal masses: Capturing kinetic pattern from early to late enhancement
Authors: Fathi Kazerooni Anahita , Nabil Mahnaz , Haghighat Khah Hamidreza , Parviz Sara , Gity Masoumeh , Saligheh Rad Hamidreza
Published: May 2017

Purpose

To develop a one‐step quantification approach that accounts for joint preprocessing and quantification of whole‐range kinetics (early and late‐phase washout) of dynamic contrast‐enhanced (DCE) MRI of indeterminate adnexal masses.

Methods

Preoperative DCE‐MRI of 43 (24 benign, 19 malignant) sonographically indeterminate adnexal masses were analyzed prospectively. A five‐parameter sigmoid function was implemented to model the enhancement curves calculated within regions of interest. Diagnostic performance of five‐parameter sigmoid model parameters (P1 through P5) was compared with pharmacokinetic (PK) modeling, semiquantitative analysis, and three‐parameter sigmoid. Statistical analysis was performed using two‐tailed student's t‐test.

Results

The results revealed that P2, representing the enhancement amplitude, is significantly higher, and P5, indicating the terminal phase, is generally negative in malignant lesions (P < 0.001). P2 (sensitivity = 79%, specificity = 87.5%, accuracy = 84%, area under the receiver operating characteristic curve = 91%) outperforms classification performances of PK and semiquantitative parameters. A combination of P2 and P5 shows comparable performance (sensitivity = 79%, specificity = 87.5%, accuracy = 84%, area under the receiver operating characteristic curve = 92%) to that of the combination of PK parameters, whereas the five‐parameter sigmoid function maintains fewer assumptions than PK.

Conclusions

The presented one‐step quantification approach is helpful for accurate discrimination of benign from malignant indeterminate adnexal masses. Accordingly, P2 has considerably high diagnostic performance and terminal slope (P5), as a previously overlooked feature, contributes more than widely accepted early‐enhancement kinetic features. Magn Reson Med 79:1165–1171, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Investigation into the effect of fault properties on wave transmission
Authors: Mohammadi H.R. , Mansouri H. , Bahaaddini M. , Jalalifar H.
Published: May 2017

The estimation of wave transmission across the fractured rock masses is of great importance for rock engineers to assess the stability of rock slopes in open pit mines. Presence of fault, as a major discontinuity, in the jointed rock mass can significantly impact on the peak particle velocity and transmission of blast waves, particularly where a fault contains a thick infilling with weak mechanical properties. This paper aims to study the effect of fault properties on transmission of blasting waves using the distinct element method. First, a validation study was carried out on the wave transmission across a single joint and different rock mediums through undertaking a comparative study against analytical models. Then, the transmission of blast wave across a fault with thick infilling in the Golgohar iron mine, Iran, was numerically studied, and the results were compared with the field measurements. The blast wave was numerically simulated using a hybrid finite element and finite difference code which then the outcome was used as the input for the distinct element method analysis. The measured uplift of hanging wall, as a result of wave transmission across the fault, in the numerical model agrees well with the recorded field measurement. Finally, the validated numerical model was used to study the effect of fault properties on wave transmission. It was found that the fault inclination angle is the most effective parameter on the peak particle velocity and uplift. Copyright © 2017 John Wiley & Sons, Ltd.
Pre‐ and postoperative magnetic resonance imaging (MRI) findings in patients treated with laparoscopic sacrocolpopexy. Is it a safe procedure for all patients?
Authors: Zacharakis Dimitrios , Grigoriadis Themos , Bourgioti Charis , Pitsouni Eleni , Protopapas Athanasios , Moulopoulos Lia A. , Athanasiou Stavros
Published: May 2017

Introduction

Laparoscopic sacrocolpopexy (LSCP) is a reference operation for apical compartment prolapse repair. Aim of this study is to describe the early and midterm postoperative MRI findings of the lumbosacral region (LSR) in patients undergoing LSCP and to detect any imaging changes that the presence of the mesh may cause on patients with preexisting degenerative disease of the LSR.

Methods

Patients with POP‐Q grade III and IV uterovaginal or vaginal vault prolapse who were considered eligible for LSCP were invited to participate. An MRI of the LSR was performed preoperatively and then 3 and 12 months postoperatively. Patients with vaginal vault prolapse underwent LSCP, while women with uterovaginal prolapse were treated with the vaginally assisted laparoscopic sacrocolpopexy (VALS).

Results

A total of 30 patients were included in the study; 18 (60%) underwent LSCP and 12 (40%) VALS. On preoperative MRIs, 83.3% (25/30) of patients had degenerative changes and 70% (21/30) reported having low back pain (LBP). Postoperative MRIs did not reveal any imaging changes compared to the preoperative MRI findings both for patients with or without preexisting degenerative abnormalities of the LSR. No significant changes in the LBP score were observed postoperatively.

Conclusions

Any bone marrow or soft‐tissue changes at MRIs of the LSR early after the insertion of a synthetic mesh, does not constitute an expected postoperative finding and should raise the suspicion of an ongoing inflammatory or infectious spinal process (spondylodiscitis). Additionally, LSCP seems to be a safe surgical approach for women with preexisting degenerative disease of the LSR.
Security in IoT network based on stochastic game net model
Authors: Kaur Rajbir , Kaur Navroop , Sood Sandeep K.
Published: May 2017

The growing prevalence of Internet of Things (IoT) ushers itself with various security concerns. Being complex in nature, traditional security countermeasures cannot be applied directly to IoT networks. Addressing this problem, this paper aims to combine the capabilities of 2 traditional methods namely, game theory (GT) and stochastic Petri nets (SPN), such that the resultant model is compatible for complex IoT networks. Game theory does not have enough modeling capability to cope up with complexity of IoT networks. However, it has an advantage of providing a priori idea of attacker's actions and strategies with the help of Nash equilibrium. This information is used by administrators to devise appropriate action plan to detect and prevent attacks on network. On the other hand, SPN is a dynamic, scalable and probabilistic model, which overcomes the limitations of GT. Nevertheless, it is not able to compute best strategies (Nash equilibrium) of attacker. Therefore, this paper proposes stochastic game net (SGN)–based model for security in IoT, which combines the advantages of SPN and GT. The novelty of the work lies in the fact that this is the first attempt to define SGN for handling security issues in IoT. Simulations performed using OPNET tool show that SGN shows 5.94% and 5.91% improvement in terms of confidentiality, 6.4% and 8% improvement in terms of integrity, and 6.7% and 8.9% improvement in terms of availability over SPN and GT, respectively.
A screening tool for predicting gatekeeping behaviour
Authors: Snowden Austyn , Young Jenny
Published: May 2017

Aim

To develop a typology and screening tool for gatekeeping behaviours by nurses responsible for recruitment in palliative care research.

Design

Concurrent analysis.

Method

Two focus groups were conducted in 2015 with nine qualified hospice community nurses involved in recruitment to a trial in palliative care. The literature was searched for research into gatekeeping from 2000–2016. All narrative examples of gatekeeping activity were coded using gerunds. Common codes were then grouped and interpreted as a social process.

Results

Gatekeeping is normal and should be expected. A continuum typology emerged, ranging from unintentional to active disengagement. Justification ranged from forgetting to deliberately not mentioning the study for fear of burdening patients. Viewing gatekeeping as a continuum allowed for the creation of a screening tool designed to collaboratively discuss and hence mitigate specific types of gatekeeping behaviour before they occur. This is a unique international contribution to this persistent issue.
A comprehensive study on controlling the porosity of CCF300/PEEK composites by optimizing the impregnation parameters
Authors: Chen Junlin , Wang Kai , Dong Anqi , Li Xuekuan , Fan Xing , Zhao Yan
Published: May 2017

In order to manufacture excellent CCF300/PEEK composites, a comprehensive study on controlling porosity of CCF300/PEEK composites was investigated by optimizing the impregnation parameters. Four kinds of PEEK with different melting flow rates (MFR) were employed to study on their rheology behavior and reveal the processing characteristics. The results showed that the viscous flow of PEEK has a higher dependence on the processing pressure than temperature. Furthermore, PEEK rheology behavior was employed to assist the optimization of impregnation parameters. PEEK powders were coated on both sides of single layer CCF300 by a preheating process, and then the semi‐impregnated forms were stacked layer by layer to manufacture CCF300/PEEK composites. An optimized impregnation prediction model was established and verified, showing a pretty effective prediction about pressure and holding time at a certain temperature to control the porosity and achieve the full impregnation. Afterwards, the well‐impregnated CCF300/PEEK composites were evaluated by their compressive performance, flexural performance and interlaminar shear performance, showing good interfacial and interlaminar bonding to resist the propagation of cracks. POLYM. COMPOS., 39:3765–3779, 2018. © 2017 Society of Plastics Engineers
Pyrene‐cored covalent organic polymers by thiophene‐based isomers, their gas adsorption, and photophysical properties
Authors: Li Changfeng , Li Peixian , Chen Linjiang , Briggs Michael E. , Liu Ming , Chen Kai , Shi Xiaoxiao , Han Deman , Ren Shibin
Published: May 2017

Two new pyrene‐cored covalent organic polymers (COPs), CK‐COP‐1 and CK‐COP‐2, were synthesized via the one‐step polymerization of two thiophene‐based isomers, 1,3,6,8‐tetra(thiophene‐2‐yl) pyrene (L1) and 1,3,6,8‐tetra(thiophene‐3‐yl) pyrene (L2). The resulting pyrene‐cored COPs exhibit rather different surface areas of 54 m2 g−1 and 615 m2g−1 for CK‐COP‐1 and CK‐COP‐2, respectively. The CO2 uptake capacities of CK‐COP‐1 and CK‐COP‐2 also show different values of 2.85 and 9.73 wt % at 273 K, respectively. Furthermore, CK‐COP‐2 offers not only a larger CO2 adsorption capacity but also a better CO2/CH4 selectivity at 273 K compared with CK‐COP‐1. CK‐COP‐1 and CK‐COP‐2 also exhibit considerable differences in their photophysical property. The different structure and properties of CK‐COPs could be attributed to the isomer effect of their corresponding thiophene‐based monomers. © 2017 Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2383–2389