bluuebunny/crossref_metadata_2025 huggingface dataset:
Coupling Eulerian‐Lagrangian method of air‐particle two‐phase flow with population balance equations to simulate the evolution of vehicle exhaust plume
Authors: He Yuanping , Gu Zhaolin , Su Junwei , Chen Chungang , Zhang Mingxu , Zhang Liyuan , Lu Weizhen
Published: May 2018

In this paper, we present a new numerical scheme to describe the dynamic evolution of multiphase polydisperse systems in terms of time, space, and properties by coupling the Eulerian‐Lagrangian method for air‐particle two‐phase flow and population balance equations to describe particle property evolution due to microbehaviors (eg, aggregation, breakage, and growth). This coupling scheme was used to comprehensively simulate the two‐phase flow structure, particle size spectrum, particle number, and volume concentrations. These were characterized by a high‐resolution particle tracking using the Lagrangian approach and the high precision of moments of the particle size spectrum by solving the population balance equation with the quadrature method of moments. The algorithm of the coupling scheme was incorporated into the open source computational fluid dynamics software OpenFOAM to simulate the dynamic evolution of vehicle exhaust plume. The impacts of vehicle velocity, exhaust temperature, and aggregation efficiency on the distribution of auto exhaust particles in space and changes in their properties were analyzed. The results indicate that the particle number concentration, volume concentration, and average diameter of particles in the vehicle exhaust plume could be strongly affected by the plume structure and flow properties.
Measurement of Proton Concentration in PEM by Hall Effect
Authors: Poljak I. , Županović P. , Barbir F.
Published: May 2018

A method based on Hall effect is applied to measure proton concentration in polymer electrolyte membrane. Although Hall effect is present in any kind of charge carriers, due to the fact that electrons are the charge carriers in any electronic device, only Hall voltage of electron systems can be measured. In this paper we show how Hall effect induces voltage on proton system in polymer electrolyte membrane (PEM) of fuel cell of the same magnitude as in the electron system. In this way it is possible to determine essential microscopic properties of the proton system in the polymer electrolyte membrane, such as proton concentration and mobility.
Optogenetic astrocyte activation evokes BOLD fMRI response with oxygen consumption without neuronal activity modulation
Authors: Takata Norio , Sugiura Yuki , Yoshida Keitaro , Koizumi Miwako , Hiroshi Nishida , Honda Kurara , Yano Ryutaro , Komaki Yuji , Matsui Ko , Suematsu Makoto , Mimura Masaru , Okano Hideyuki , Tanaka Kenji F.
Published: May 2018

Functional magnetic resonance imaging (fMRI) based on the blood oxygenation level‐dependent (BOLD) signal has been used to infer sites of neuronal activation in the brain. A recent study demonstrated, however, unexpected BOLD signal generation without neuronal excitation, which led us to hypothesize the presence of another cellular source for BOLD signal generation. Collective assessment of optogenetic activation of astrocytes or neurons, fMRI in awake mice, electrophysiological measurements, and histochemical detection of neuronal activation, coherently suggested astrocytes as another cellular source. Unexpectedly, astrocyte‐evoked BOLD signal accompanied oxygen consumption without modulation of neuronal activity. Imaging mass spectrometry of brain sections identified synthesis of acetyl‐carnitine via oxidative glucose metabolism at the site of astrocyte‐, but not neuron‐evoked BOLD signal. Our data provide causal evidence that astrocytic activation alone is able to evoke BOLD signal response, which may lead to reconsideration of current interpretation of BOLD signal as a marker of neuronal activation.
A facile and sustainable protocol to the preparation of aryl iodides using stable arenediazonium bis(trifluoromethylsulfonyl)imide salts via the telescopic process
Authors: Khaligh Nader Ghaffari
Published: May 2018

The preparation of aryl iodides in a telescopic reaction using tert‐butyl nitrite as a diazotization reagent and a mixture of bis(trifluoromethane) sulfonamide and glacial acetic acid as a mild acidic agent in ethanol followed by iododediazoniation with tetraethylammonium iodide in water was investigated. The current method has other advantages such as minimized waste by avoiding solvent for the purification of products in diazotization step, simple experimental procedure, and good yield of the sterically hindered aryl amines, metal and strong acid‐free waste and environmentally benign conditions. The noteworthy features of this study are the preparation of stable arenediazonium bis(trifluoromethylsulfonyl)imide salts that can be used with no significant loss activity after 1 week and bis(trifluoromethane)sulfonamide was recovered in high yields from reactions.
Synthesis of new functionalized hydroxy‐ and aminomethylphosphinates with indan moieties
Authors: Prishchenko Andrey A. , Livantsov Mikhail V. , Novikova Olga P. , Livantsova Ludmila I. , Petrosyan Valery S.
Published: May 2018

The convenient synthesis of new functionalized organophosphorus acids and their derivatives containing indan moieties was developed. The regioselective radical addition of bis(trimethylsiloxy)phosphine to indene proceeds to give rise to 2‐indanylphosphonite as key compound for preparation of above acids with bicyclic substituents. Azobis(isobutyronitrile) (AIBN) in the conditions of its thermolysis was used as effective initiator of the addition reaction. The further treatment of organophosphorus acids trimethylsilyl esters with the methanolic sodium methoxide solution resulted in the water‐soluble sodium salts of the corresponding acids.
Assessing the impacts of microtopography on soil erosion under simulated rainfall, using a multifractal approach
Authors: Luo Jian , Zheng Zicheng , Li Tingxuan , He Shuqin
Published: May 2018

This study aimed to investigate the changing characteristics of microrelief of purple soil and its erosional response during successive stages of water erosion, including splash erosion, sheet erosion, and rill erosion. Methods employed included a rainfall simulator and the use of a laser scanner to generate a digital elevation model. Three artificial tillage practices, including conventional tillage (CT), artificial digging (AD), and ridge tillage (RT), were used to simulate different microrelief patterns. Eighteen artificial rainfall experiments were conducted using three 2 × 1 m boxes with a rainfall intensity of 1.5 mm min−1 on a 15° slope. The results showed that the soil roughness (SR) index values for the tillage slopes were RT > AD > CT. The combined effects of detachment by raindrop impact and transport by run‐off decreased the SR index, whereas rill erosion increased the SR index during rainfall event. Microtopography and drainage networks have strong multifractal behaviours. The multifractal parameters of microtopography reflect the overall characteristics as well as the characteristics of the local soil surface. Within a certain range of threshold values, higher microrelief causes less soil erosion. However, when the parameters of spatial heterogeneity of microtopography exceed the threshold values, a higher degree of microrelief can increase soil erosion. These results help clarify the effect of microtopography on soil erosion and provide a theoretical foundation to guide future tillage practices on sloping farmland of purple soil.
Gender‐neutral vaccination provides improved control of human papillomavirus types 18/31/33/35 through herd immunity: Results of a community randomized trial (III)
Authors: Lehtinen Matti , Luostarinen Tapio , Vänskä Simopekka , Söderlund‐Strand Anna , Eriksson Tiina , Natunen Kari , Apter Dan , Baussano Iacopo , Harjula Katja , Hokkanen Mari , Kuortti Marjo , Palmroth Johanna , Petäjä Tiina , Pukkala Eero , Rekonen Sirpa , Siitari‐Mattila Mari , Surcel Heljä‐Marja , Tuomivaara Leena , Paavonen Jorma , Nieminen Pekka , Dillner Joakim , Dubin Gary , Garnett Geoff
Published: May 2018

With optimal strategy, human papillomavirus (HPV) vaccines have the potential to control HPV. We have assessed vaccine efficacy (VE), herd effect (HE) of HPV vaccination and overall protective effectiveness (PE) against high‐risk HPV infections by HPV type and vaccination strategy in a community‐randomized trial using the bivalent HPV16/18 vaccine. We randomized 33 communities to gender‐neutral HPV vaccination (Arm A), HPV vaccination of girls and hepatitis B‐virus (HBV) vaccination of boys (Arm B) and gender‐neutral HBV vaccination (Arm C). Entire 1992–1995 male (40,852) and female (39,420) birth cohorts were invited, and 11,662 males and 20,513 females vaccinated with 20–30% and 45% coverage in 2007–2010. During 2010–2014, 11,396 cervicovaginal samples were collected from 13,545 18.5‐year‐old attendees. HPV typing was performed by a high‐throughput PCR. VE was calculated for HPV vaccinated women and HE for non‐HPV‐vaccinated women, using the HBV vaccinated, for HE all non‐HPV vaccinated, Arm C women as controls. PE was calculated as coverage rate‐weighted mean of VE + HE. HPV16/18/45 and 31/33/35 VEs varied between 86–94% and 30–66%, respectively. Only the gender‐neutral vaccination provided significant HEs against HPV18 (61%) and HPV31 (72%) in the 1995 birth cohort—increased HEs against HPV33 (39%) and HPV35 (42%) were also observed. Due to the increased HEs, PEs for HPV16/18/45 and HPV31/33/35 were comparable in the gender‐neutral arm 1995 birth cohort. High vaccine efficacy against HPV16/18/45 and, gender‐neutral vaccination‐enforced, herd effect against HPV18/31/33/35 by the bivalent vaccine rapidly provides comparable overall protective effectiveness against six oncogenic HPV types: 16/18/31/33/35/45.
Pillar[n]arenes for Construction of Artificial Transmembrane Channels
Authors: Feng Wei‐Xu , Sun Zhanhu , Barboiu Mihail
Published: May 2018

Pillar[n]arenes have been intensively used during the last decade in supramolecular chemistry as host systems for guest recognition and self‐assembly, toward functional materials and devices. They present electron‐rich and tuneable size cavities, as well as reactive rims for further functionalization. Their unique pillar shape promotes pillar[n]arenes as molecular analogues of carbon nanotubes. For this reasons pillar[n]arenes have been embedded into membranes and used to construct artificial water, proton, ions and molecular channels. This review discusses the incipient developments of the first artificial channels based on pillar[n]arenes. We include also systems that integrate pillar[n]arenes as synthetic elements for the construction of selective pores of nanodevices for ion rectification.
Widening the arc of indigenous communication: Examining potential for use of ICT in strengthening social and behavior change communication efforts with marginalized communities in India
Authors: Malhotra Alka , Sharma Rachana , Srinivasan Raghavan , Mathew Nirmala
Published: May 2018

Marginalized communities in India have their own systems of governance, culture, and communication. They remain socially and physically distanced from mainstream methods of communication. At the same time, India is witnessing a digital revolution, represented by a phenomenal growth in mobile and internet penetration. To date, however, scholarly discourse on use of ICT among marginalized communities in India has, for the most part, been limited.

Four related field studies initiated by UNICEF revealed that melding indigenous (local) and mainstream communication channels can be an optimal approach to social and behavior change communication with marginalized communities across multiple social development themes. They indicated the increasing popularity of mobile and other digital media among marginalized communities, especially youth, and the potential for utilizing local communication methods along with new digital media. This hypothesis is supported by findings from one of the field studies, a digital training and communication tools/materials pilot for frontline workers, to improve nutrition behaviors among marginalized communities. They also provided field evidence for the efficacy of mobile technology in civic participation, education, and health. These findings have far‐reaching import for designing inclusive social and behavior change communication programs for marginalized communities where local and mainstream channels (particularly digital) complement each other.
A matrix‐assisted laser desorption ionization–time‐of‐flight–time‐of‐flight–mass spectrometry‐based toxicoproteomic screening method to assess in vitro particle potencies
Authors: Ariganello Marianne B. , Das Dharani D. , Breznan Dalibor , MacKinnon‐Roy Christine , Elisma Fred , Khanchi Aziz , Vincent Renaud , Kumarathasan Prem
Published: May 2018

Knowledge of biological reactivity and underlying toxicity mechanisms of airborne particulate matter (PM) is central to the characterization of the risk associated with these pollutants. An integrated screening platform consisting of protein profiling of cellular responses and cytotoxic analysis was developed in this study for the estimation of PM potencies. Mouse macrophage (J774A.1) and human lung epithelial cells (A549) were exposed in vitro to Ottawa urban particles (EHC6802) and two reference mineral particles (TiO2 and SiO2). Samples from the in vitro exposure experiment were tested following an integrated classical cytotoxicity/toxicoproteomic assessment approach for cellular viability (CellTiter Blue®, lactate dehydrogenase) and proteomic analyses. Cellular proteins were pre‐fractionated by molecular weight cut‐off filtration, digested enzymatically and were analyzed by matrix‐assisted laser desorption ionization–time‐of‐flight–time‐of‐flight–mass spectrometry for protein profiling and identification. Optimization of detergent removal, pre‐fractionation strategies and enzymatic digestion procedures led to increased tryptic peptide (m/z) signals with reduced sample processing times, for small total protein contents. Proteomic analyses using this optimized procedure identified statistically significant (P < 0.05) PM dose‐dependent changes at the molecular level. Ranking of PM potencies based on toxicoproteomic analysis were in line with classical cytotoxicity potency‐based ranking. The high content toxicoproteomic approach exhibited the potential to add value to risk characterization of environmental PM exposures by complementing and validating existing cytotoxicity testing strategies.
Ultrafast dynamics of hard tissue ablation using femtosecond‐lasers
Authors: Domke Matthias , Wick Sebastian , Laible Maike , Rapp Stephan , Huber Heinz P. , Sroka Ronald
Published: May 2018

Several studies on hard tissue laser ablation demonstrated that ultrafast lasers enable precise material removal without thermal side effects. Although the principle ablation mechanisms have been thoroughly investigated, there are still open questions regarding the influence of material properties on transient dynamics. In this investigation, we applied pump‐probe microscopy to record ablation dynamics of biomaterials with different tensile strengths (dentin, chicken bone, gallstone and kidney stones) at delay times between 1 picosecond and 10 microseconds. Transient reflectivity changes, pressure and shock wave velocities and elastic constants were determined. The result revealed that absorption and excitation show the typical well‐known transient behavior of dielectric materials. We observed for all samples a photomechanical laser ablation process, where ultrafast expansion of the excited volume generates pressure waves leading to fragmentation around the excited region. In addition, we identified tensile‐strength‐related differences in the size of ablated craters and ejected particles. The elastic constants derived were in agreement with literature values. In conclusion, pressure‐wave‐assisted material removal seems to be a general mechanism for hard tissue ablation with ultrafast lasers. This photomechanical process increases ablation efficiency and removes heated material, thus ultrafast laser ablation is of interest for clinical application where heating of the tissue must be avoided.
In vivo optical imaging of the viable epidermis around the nailfold capillaries for the assessment of heart failure severity in humans
Authors: Shirshin Evgeny A. , Gurfinkel Yury I. , Matskeplishvili Simon T. , Sasonko Maria L. , Omelyanenko Nikolai P. , Yakimov Boris P. , Lademann Juergen , Darvin Maxim E.
Published: May 2018

Heart failure (HF) is among the socially significant diseases, involving over 2% of the adult population in the developed countries. Diagnostics of the HF severity remains complicated due to the absence of specific symptoms and objective criteria. Here, we present an indicator of the HF severity based on the imaging of tissue parameters around the nailfold capillaries. High resolution nailfold video capillaroscopy was performed to determine the perivascular zone (PZ) size around nailfold capillaries, and 2‐photon tomography with fluorescence lifetime imaging was used to investigate PZ composition. We found that the size of PZ around the nailfold capillaries strongly correlates with HF severity. Further investigations using 2‐photon tomography demonstrated that PZ corresponds to the border of viable epidermis and it was suggested that the PZ size variations were due to the different amounts of interstitial fluid that potentially further translates in clinically significant oedema. The obtained results allow for the development of a quantitative indicator of oedematous syndrome, which can be used in various applications to monitor the dynamics of interstitial fluid retention. We therefore suggest PZ size measured with nailfold video capillaroscopy as a novel quantitative sensitive non‐invasive marker of HF severity.
Size‐tunable two‐dimensional Pd@Au nanoplates as a platform for fluorescence sensing
Authors: Wang Yaya , Chen Mei , Wang Song , Du Shuo , Zheng Xiaofang , Jiang Xi , Huan Shuangyan , Zhang Xiaobing
Published: May 2018

Two‐dimensional (2D) nanomaterials have been widely used as novel biosensing platforms, but it is still a challenge to synthesize such materials with controlled shape, composition, and structure for further application in analytical sensing devices. In this work, through a seeded regrowth method, uniform hexagonal Pd@Au nanoplates with well‐defined thicknesses and tunable sizes were synthesized. The Pd@Au nanoplates showed strong absorption in the visible and near‐infrared spectral range, which contributed to their high fluorescence quenching ability. In particular, the Pd@Au nanoplates exhibited different affinities toward single‐stranded DNA (ssDNA) and double‐stranded DNA (dsDNA). As a proof of concept, Pd@Au nanoplates were applied for the first time as a highly efficient fluorescent sensing platform for the rapid, sensitive, and selective detection of DNA and small molecules. This work further provides an avenue for understanding the interaction between 2D nanomaterials and biomolecules, which will definitely stimulate more interest in designing novel sensing platforms for extending the applications of nanomaterials in bioanalysis.
A meta‐analysis of empowerment and voice as transmitters of high‐performance managerial practices to job performance
Authors: Chamberlin Melissa , Newton Daniel W. , LePine Jeffery A.
Published: May 2018

Empowerment offers the predominant explanation for why employee perceptions of high‐performance managerial practices are positively associated with employee job performance. Drawing on social cognitive theory, we propose that high‐performance managerial practices also influence performance because these practices encourage employees to engage in voice. Additionally, we suggest that empowerment and voice together provide a more complete explanation for why high‐performance managerial practices and job performance are linked. In essence, we argue that empowerment transmits the effects of high‐performance managerial practices to job performance because it engenders voice. Using meta‐analysis of primary research consisting of 151 independent samples involving 53,200 employees, we find that not only do empowerment and voice independently transmit the effects of high‐performance managerial practices to job performance, but they sequentially mediate this relationship as well. Further, we distinguish among skill‐enhancing, motivation‐enhancing, and opportunity‐enhancing high‐performance managerial practices to identify when empowerment and voice are more or less effective in explaining associations with job performance. Although empowerment and voice transmit effects of all 3 types of high‐performance managerial practices to employee performance, these mechanisms appear to provide the best explanation for the effects of opportunity‐enhancing practices, and the primary reason why is because employees respond to opportunity‐enhancing practices with voice.
When does performance management foster team effectiveness? A mixed‐method field study on the influence of environmental extremity
Authors: Van Thielen Tine , Decramer Adelien , Vanderstraeten Alex , Audenaert Mieke
Published: May 2018

Organizations operating in extreme environments rely on teams to tackle the highly demanding and complex situations. This study aims to provide new insights into the management of such teams by exploring the influence of environmental extremity on the relationship between performance management and team effectiveness. Mixed‐method and multilevel analyses of police teams working in different levels of environmental extremity suggest that environmental extremity moderates the relationship between performance management features and team effectiveness. Both the vertical alignment of performance management and constructive feedback have a positive effect on team effectiveness. However, these positive effects are constrained in teams working in heightened levels of environmental extremity. The effects of performance management consistency and two‐way communication on team effectiveness are more nuanced and dependent on environmental extremity. When teams operate in heightened levels of environmental extremity, both features are positively related to team effectiveness. When teams operate in lower levels of environmental extremity, performance management consistency is not significantly related to team effectiveness and two‐way communication is negatively related to team effectiveness. These results provide a nuanced understanding of how performance management engenders team effectiveness in extreme environments.
Nutrition Risk in Critically Ill Versus the Nutritional Risk Screening 2002: Are They Comparable for Assessing Risk of Malnutrition in Critically Ill Patients?
Authors: Canales Cecilia , Elsayes Ali , Yeh D. Dante , Belcher Donna , Nakayama Anna , McCarthy Caitlin M. , Chokengarmwong Nalin , Quraishi Sadeq A.
Published: May 2018

Background

Malnutrition influences clinical outcomes. Although various screening tools are available to assess nutrition status, their use in the intensive care unit (ICU) has not been rigorously studied. Our goal was to compare the Nutrition Risk in Critically Ill (NUTRIC) to the Nutritional Risk Screening (NRS) 2002 in terms of their associations with macronutrient deficit in ICU patients.

Methods

We performed a retrospective analysis to investigate the relationship between NUTRIC vs NRS 2002 and macronutrient deficit (protein and calories) in critically ill patients. We performed linear regression analyses, controlling for age, sex, race, body mass index, and ICU length of stay. We then dichotomized our primary exposures and outcomes to perform logistic regression analyses, controlling for the same covariates.

Results

The analytic cohort included 312 adults. Mean NUTRIC and NRS 2002 scores were 4 ± 2 and 4 ± 1, respectively. Linear regression demonstrated that each increment in NUTRIC score was associated with a 49 g higher protein deficit (β = 48.70: 95% confidence interval [CI] 29.23–68.17) and a 752 kcal higher caloric deficit (β = 751.95; 95% CI 447.80–1056.09). Logistic regression demonstrated that NUTRIC scores >4 had over twice the odds of protein deficits ≥300 g (odds ratio [OR] 2.35; 95% CI 1.43–3.85) and caloric deficits ≥6000 kcal (OR 2.73; 95% CI 1.66–4.50) compared with NUTRIC scores ≤4. We did not observe an association of NRS 2002 scores with macronutrient deficit.

Conclusion

Our data suggest that NUTRIC is superior to NRS 2002 for assessing malnutrition risk in ICU patients. Randomized, controlled studies are needed to determine whether nutrition interventions, stratified by NUTRIC score, can improve patient outcomes.
Essential Fatty Acid Status in Surgical Infants Receiving Parenteral Nutrition With a Composite Lipid Emulsion: A Case Series
Authors: Carey Alexandra N. , Rudie Coral , Mitchell Paul D. , Raphael Bram P. , Gura Kathleen M. , Puder Mark
Published: May 2018

Infants requiring prolonged parenteral nutrition (PN) may receive intravenous (IV) lipid in the form of soybean oil, fish oil, or a composite lipid emulsion (CLE) (i.e., SMOFlipid®). Soybean oil lipid‐dose restriction is a popular method of treating and reducing the risk of intestinal failure–associated liver disease (IFALD) that may influence dosing strategies of other IV fat emulsions. Here we present 4 infants receiving PN with SMOFlipid® as their IV lipid source and examine trends in essential fatty‐acid status, triglycerides, and dosing strategy. The infants on restricted doses of CLE developed biochemical essential fatty‐acid deficiency (EFAD) that resolved with a dosage increase or by transition to a pure fish‐oil lipid emulsion. Three of the 4 infants originally prescribed CLE were diagnosed with IFALD and started a pure fish‐oil lipid emulsion after treatable causes of cholestasis were excluded. One of the 4 infants presented with hypertriglyceridemia that resolved upon transition to pure fish‐oil lipid emulsion. Misapplication of lipid restriction protocols to CLE regimens render infants at risk for EFAD. CLE should be dosed within recommended ranges to prevent EFAD. Restricted protocols warrant close monitoring of essential fatty‐acid status in infants receiving prolonged PN, particularly in those with minimal or no enteral intake. Hypertriglyceridemia and cholestasis are known adverse effects of CLE and require monitoring.
Isolation and characterization of progenitor cells from surgically created early healing alveolar defects in humans: A preliminary study
Authors: Sant'Ana Adriana Campos Passanezi , Damante Carla Andreotti , Frias Martinez Maria Alejandra , Valdivia Maria Alejandra Medina , Karam Paula Stefânia Hage , de Oliveira Flavia Amadeu , Oliveira Rodrigo Cardoso de , Gasparoto Thais Helena , Campanelli Ana Paula , Zangrando Mariana Schutzer Ragghianti , Rezende Maria Lúcia Rubo de , Greghi Sebastião Luiz Aguiar , Passanezi Euloir
Published: May 2018

Background

The granulation tissue present in surgically‐created early healing sockets has been considered as a possible source of osteoprogenitor cells for periodontal regeneration, as demonstrated in animal studies. However, the in vitro osteogenic properties of tissue removed from human surgically‐created early healing alveolar defects (SC‐EHAD) remains to be established, being that the aim of this study.

Methods

Surgical defects were created in the edentulous ridge of two systemically healthy adults. The healing tissue present in these defects was removed 21 days later for the establishment of primary culture. The in vitro characteristics of the cultured cells were determined by Armelin method, 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay, immunohistochemistry, alkaline phosphatase (ALP) activity, mineralization assay, and flow cytometry for detection of stem cells/osteoprogenitor cell markers.

Results

Cells were able to adhere to the plastic and assumed spindle‐shaped morphology at earlier passages, changing to a cuboidal one with increasing passages. Differences in the proliferation rate were observed with increasing passages, suggesting osteogenic differentiation. ALP and mineralization activities were detected in conventional and osteogenic medium. Fresh samples of SC‐EHAD tissue exhibited CD34− and CD45− phenotypes. Cells at later passages (14th) exhibited CD34−, CD45−, CD105−, CD166−, and collagen type I+ phenotype.

Conclusion

Tissue removed from SC‐EHAD is a possible source of progenitor cells.
Micro‐Raman spectroscopy of natural members along CuSbS2–CuSbSe2 join
Authors: Sejkora Jiří , Buixaderas Elena , Škácha Pavel , Plášil Jakub
Published: May 2018

Micro‐Raman spectroscopy was used to investigate the natural orthorhombic members (space group Pnma) along the CuSbS2–CuSbSe2 join: chalcostibite Cu1.01Sb1.00S1.99 from Dúbrava (Slovak Republic); Se‐rich chalcostibite Cu1.00(Sb0.99As0.02)Σ1.01(S1.29Se0.70)Σ1.99 and the new mineral příbramite Cu0.99(Sb1.03As0.01)Σ1.04(Se1.82S0.15)Σ1.97 both from the Příbram uranium and base‐metal district (Czech Republic). Stretching and bending vibrations of the pyramidal SbS3 groups occur between 350 and 200 cm−1; vibrations of SbSe3 groups are shifted to the range 240–80 cm−1 due to the almost twice heavier mass of Se compared with S. The shift of the ν1 symmetric Sb‐(S,Se) vibration was observed, yielding 113 cm−1, and for the ν3 antisymmetric stretching Sb‐(S,Se), vibration was about 127 cm−1. The wavenumber of the ν1 symmetric Sb–S stretching vibrations decreases with increasing Se content—from 336 (in chalcostibite) over 330 (in Se‐rich chalcostibite) to 326 cm−1 (in příbramite), and a similar situation was observed for the case of ν1 symmetric Sb–Se stretching vibrations from 220 in Se‐rich chalcostibite to 215 cm−1 in příbramite. The trend for the ν3 antisymmetric Sb‐(S,Se) stretching vibrations is the opposite, from 306 cm−1 in chalcostibite to 314 cm−1 in Se‐rich chalcostibite (Sb–S bonds) and from 180 cm−1 in Se‐rich chalcostibite to 185 cm−1 in příbramite (Sb–Se bonds). These small shifts are probably connected with the influencing of the bonding environment of SbS3 and SbSe3 pyramids. The vibrations of Cu‐S(Se) bonds are represented only by less intense bands, and the observed intense bands below 80 cm−1 should correspond to external modes.
Roles of iron and lithium in silicate glasses by Raman spectroscopy
Authors: Nayak Manjunath T. , Desa J.A. Erwin
Published: May 2018

Raman spectroscopy has been used in a qualitative analysis of iron containing lithium silicate glasses. The iron was kept fixed at 8 mol% for all the iron containing samples with varying concentrations of Li2O and SiO2, as this resulted in samples that were fully vitreous in nature. The method of deconvolution of peaks in these data has been employed to understand the relative numbers of Q0, Q1, Q2, Q3, and Q4 silicate structural units. Even though the iron concentration is constant, the linkages of silicate structural units show variation with increasing alkali content. The roles of lithium and iron have been found to be opposed to each other in that the presence of lithium discourages formation of tetrahedral linkages in the structure, whereas iron promotes corner connected tetrahedra or the presence of bridging oxygens.
Incorporation of Metallic Nanoparticles into Cosmetic Preparations and Assessment of Their Physicochemical and Utility Properties
Authors: Pulit‐Prociak Jolanta , Chwastowski Jarosław , Siudek Mateusz , Banach Marcin
Published: May 2018

A method was developed for introducing metallic nanoparticles (nanoAg and nanoAu) into cosmetic compositions (shampoos and soaps). Embedding of silver or gold nanoparticles into the composition imparts antimicrobial activity. Physicochemical properties of the prepared formulations were characterized. To confirm the presence of metallic nanoparticles, a UV–vis study was conducted. The size of embedded nanoparticles was determined using dynamic light scattering. The micrometric structure of the obtained products was characterized using scanning electron microscopy with energy‐dispersive X‐ray spectroscopy (SEM‐EDS) microscopy. A technique was developed for the assessment of nanoparticle release from cosmetic products as well as for the analysis of the penetration of nanoparticles through a model dermal membrane. The evaluation of accumulation of nanoparticles in model human body fluids was a crucial step in this study. The antimicrobial properties of final cosmetic formulations were studied usingAspergillus niger. The results confirmed that stable cosmetic formulations with embedded metallic nanoparticles were obtained. It was determined that nanoparticles are able to penetrate through a model dermal membrane. However, after 20 min of washing, the migration of nanoparticles was not confirmed. The obtained products exhibited biocidal activity againstA. niger.
Compressive behaviour of additively manufactured AlSi10Mg
Authors: Hitzler L. , Schoch N. , Heine B. , Merkel M. , Hall W. , Öchsner A.
Published: May 2018

The advantages of free form fabrication methods regarding the geometrical flexibility are well known. With the full melting approach of the raw material, as utilized in selective laser melting, this freedom in design is coupled with remarkable mechanical strength. Most studies focused on the tensile characteristics; this study investigates the direction dependent compressive behaviour of selective laser melted AlSi10Mg. The obtained compressive Young's moduli exceeded both the equivalent Young's moduli for the tensile loading and the Young's modulus of the isotropic, conventionally fabricated, bulk base material, ranging as high as 82 GPa. The compressive yield strength was found to be similar to the yield point in tensile loading, with the ultimate compressive stress and strain being far superior to their tensile counterpart.
Electron beam welding of copper‐niobium microcomposites for pulsed power applications
Authors: Višniakov N. , Mikalauskas G. , Černašėjienė R. , Černašėjus O. , Škamat J.
Published: May 2018

The main objective of this work is to explore the possibility of applying electron beams to connect copper‐niobium conductors. Electron beam welding of copper–niobium microcomposite wires was investigated. The evaluation of welded joint properties was carried out according to the same methodology applied to contact electrical connections. The major electrical and mechanical properties of welded joints were established. The microscopic examination of the joint cross‐section showed that welded joints of copper‐niobium conductors have minimal thermal effects on the structure of the conductor and on the propagation of welding defects thanks to the welding in a vacuum. According to the non‐destructive radiographic test, the joint structure does not have welding defects. The difference in electrical resistances of the conductor and welded joint was below 20 %. The welded joint can withstand the maximum load, which is equal to 31.25 % of the load‐bearing capacity of microcomposite conductor.
Entwicklung von topologieoptimierten Adapterelementen für die Fertigung mittels additiver Verfahren: Vereinigung von reinelektrischem Antriebsstrang mit konventionellem Chassis
Authors: Sert E. , Hitzler L. , Merkel M. , Öchsner A.
Published: May 2018

Ein zentrales Element ist die Zunahme des Verkehrsaufkommens und der Wunsch nach individueller Mobilität. Die Menge der ausgestoßenen Abgase steigt in erheblichem Maße an und führt in Ballungsräumen und Innenstädten zu Umweltbelastungen und einer Beeinträchtigung der Lebensqualität. Ein Ansatz diesem Trend entgegenzuwirken, liegt in der Reduktion der ausgestoßenen Abgase und dem damit einhergehenden Verbrauch fossiler Energieträger. Der durch das Umdenken und dem damit verbundenen gesteigerten Umweltbewusstsein entstandene Bedarf an elektrisch betriebenen Fahrzeugen bringt einige Anforderungen, hinsichtlich der Entwicklung und Konstruktion künftiger Mobilitätslösungen, mit sich. Eine der Herausforderungen ist unter anderem die Entwicklung von modularen und skalierbaren Antriebseinheiten, um eine Serienproduktion und Elektroumrüstungen im kostengünstigen Maße zu ermöglichen. Für die Neukonstruktion einer elektrisch angetriebenen Achse oder die Umrüstung einer bestehenden Achse auf einen Elektroantrieb sind umfangreiche Aufgaben durchzuführen. Dabei ist die Anwendung von Topologieoptimierungstools und additiven Fertigungsverfahren unerlässlich.
Computational aspects of the combined finite‐discrete element method in static and dynamic analysis of shell structures
Authors: Glavinić I.U. , Smoljanović H. , Galić M. , Munjiza A. , Mihanović A.
Published: May 2018

This paper demonstrates some computational aspects of two previously developed numerical models for a static and dynamic analysis of shells based on the combined finite‐discrete element method. The dynamic and static response of shells under various boundary conditions, mesh pattern and mesh refinement was analysed and compared with other numerical and analytical results in order to illustrate the accuracy and applicability of the proposed numerical models.
A computationally efficient numerical model for a dynamic analysis of beam type structures based on the combined finite‐discrete element method
Authors: Smoljanović H. , Uzelac I. , Trogrlić B. , Živaljić N. , Munjiza A.
Published: May 2018

This paper presents a new numerical model for the analysis of beam‐type structures based on the combined finite‐discrete element method. The model uses straight two‐node rotation free finite elements, and takes into account linear‐elastic material behaviour, finite displacements, finite rotations and small strains. The presented numerical model is implemented into the open source finite‐discrete element method package “Yfdem”. Performance of the new numerical model was demonstrated on simple benchmark tests where very good agreement of obtained numerical results with reference solutions was shown. Performed numerical analysis indicates that the presented numerical model is applicable in static, dynamic and stability analyses of beam type structures.
Development of a new stainless austenitic CrMnNi steel using TRIP/TWIP effect for a high cold formability
Authors: Schröder C. , Weiß A. , Volkova O.
Published: May 2018

A new austenitic stainless CrMnNi steel with a high cold formability coupled with high strength was developed. The cold formability is based on the distinct transformation induced plasticity (TRIP) and twinning induced plasticity (TWIP). Thereby a maximum of strain is reached nearby room temperature. Using the TRIP/TWIP effect of CrMnNi steel a cost‐ and energy‐efficient production of thin sheets is enabled by a reduced number of interstage annealing. Thin sheets with thicknesses from 0.1 mm till 1.25 mm were cold‐rolled industrially and there properties compared to conventional CrNi steel 1.4301 (AISI 304) and CrNiMo steel 1.4404 (AISI 316 L).Plate and lamellae heat exchangers of CrMnNi thin sheets were produced under industrial conditions. The form stability of the plate heat exchangers was increased by 47 % and the component failure pressure raised by 45 % at room temperature. Based on its high strength it is suggested to apply the new austenitic CrMnNi steel in lightweight constructions. Although the nickel content was reduced by 50 % to 65 % compared to conventional steels 1.4301 and 1.4404 the corrosion resistance of the CrMnNi steel is comparable with conventional CrNiMo steel 1.4404.
Effect of short duration solution treatment at temperatures below 1000 °C on σ‐phase precipitation in a super duplex stainless steel alloy
Authors: Cojocaru V.D. , Şerban N. , Angelescu M.L. , Cojocaru E.M. , Cinca I. , Răducanu D. , Vintilă A.N.
Published: May 2018

Super duplex stainless steel alloys are characterized by a high content of chromium, nickel, molybdenum and nitrogen. In these steels, the main role of chromium, nickel and molybdenum alloying elements is to increase corrosion resistance. Increased mechanical properties are obtained by adding nitrogen, which promotes structural hardening. The microstructure of super duplex stainless steels consists of a mixture of ferrite and austenite phases, while other phases are also formed, such as: sigma, chi, chromium nitride, carbides and secondary austenite. All secondary phases are considered deleterious phases due to their negative effect on corrosion resistance and mechanical properties. The precipitation formation mechanism of the sigma phase assumes depletion of chromium and molybdenum from the matrix, worsening the alloy properties. The aim of the present work is to show the microstructural changes occurring during a short duration (10 minutes) solution treating of an UNS S32760/1.4501/F55 alloy, three temperatures being considered: 800 °C, 900 °C and 1000 °C. Scanning electron microscopy (energy dispersive spectroscopy and electron backscattered diffraction) was used for quantifying the alloying elements distribution, to distinguish between the observed phases, and to better understand the evolution of each phase.
Chitosan‐based multifunctional nanomedicines and theranostics for targeted therapy of cancer
Authors: Fathi Marziyeh , Majidi Sima , Zangabad Parham Sahandi , Barar Jaleh , Erfan‐Niya Hamid , Omidi Yadollah
Published: May 2018

Nanotechnology as an emerging field has established inevitable impacts on nano‐biomedicine and treatment of formidable diseases, inflammations, and malignancies. In this regard, substantial advances in the design of systems for delivery of therapeutic agents have emerged magnificent and innovative pathways in biomedical applications. Chitosan (CS) is derived via deacetylation of chitin as the second most abundant polysaccharide. Owing to the unique properties of CS (e.g., biocompatibility, biodegradability, bioactivity, mucoadhesion, cationic nature and functional groups), it is an excellent candidate for diverse biomedical and pharmaceutical applications such as drug/gene delivery, transplantation of encapsulated cells, tissue engineering, wound healing, antimicrobial purposes, etc. In this review, we will document, discuss, and provide some key insights toward design and application of miscellaneous nanoplatforms based on CS. The CS‐based nanosystems (NSs) can be employed as advanced drug delivery systems (DDSs) in large part due to their remarkable physicochemical and biological characteristics. The abundant functional groups of CS allow the facile functionalization in order to engineer multifunctional NSs, which can simultaneously incorporate therapeutic agents, molecular targeting, and diagnostic/imaging capabilities in particular against malignancies. These multimodal NSs can be literally translated into clinical applications such as targeted diagnosis and therapy of cancer because they offer minimal systemic toxicity and maximal cytotoxicity against cancer cells and tumors. The recent developments in the CS‐based NSs functionalized with targeting and imaging agents prove CS as a versatile polymer in targeted imaging and therapy.
Sommerfeld's solution as the limiting amplitude and asymptotics for narrow wedges
Authors: Komech A. I. , Merzon A. E. , Esquivel Navarrete A. , De La Paz Méndez J. E. , Villalba Vega T. J.
Published: May 2018

We analyze the Sommerfeld solution to the stationary diffraction by a half‐plane. We prove that this solution is the limiting amplitude for time‐dependent scattering of incident plane waves with a broad class of the profile functions. We also show that this solution is the asymptotics of the limiting amplitudes of solutions to time‐dependent scattering problem with narrow wedges when the angle of the wedge tends to zero.
Boundary value problems on half‐line for second‐order nonlinear impulsive differential equations
Authors: Akgol S.D. , Zafer A.
Published: May 2018

We obtain sufficient conditions for existence and uniqueness of solutions of boundary value problems on half‐line for a class of second‐order nonlinear impulsive differential equations. Our technique is different than the traditional ones, as it is based on asymptotic integration method involving principal and nonprincipal solutions. Examples are provided to illustrate the relevance of the results.
Assessment of renal fibrosis in murine diabetic nephropathy using quantitative magnetization transfer MRI
Authors: Wang Feng , Katagiri Daisuke , Li Ke , Takahashi Keiko , Wang Suwan , Nagasaka Shinya , Li Hua , Quarles C. Chad , Zhang Ming‐Zhi , Shimizu Akira , Gore John C. , Harris Raymond C. , Takahashi Takamune
Published: May 2018

Purpose

Renal fibrosis is a hallmark of progressive renal disease; however, current clinical tests are insufficient for assessing renal fibrosis. Here we evaluated the utility of quantitative magnetization transfer MRI in detecting renal fibrosis in a murine model of progressive diabetic nephropathy (DN).

Methods

The db/db eNOS‐/‐ mice, a well‐recognized model of progressive DN, and normal wild‐type mice were imaged at 7T. The quantitative magnetization transfer data were collected in coronal plane using a 2D magnetization transfer prepared spoiled gradient echo sequence with a Gaussian‐shaped presaturation pulse. Parameters were derived using a two‐pool fitting model. A normal range of cortical pool size ratio (PSR) was defined as Mean±2SD of wild‐type kidneys (N = 20). The cortical regions whose PSR values exceeded this threshold (threshold PSR) were assessed. The correlations between the PSR‐based and histological (collagen IV or picrosirius red stain) fibrosis measurements were evaluated.

Results

Compared with wild‐type mice, moderate increases in mean PSR values and scattered clusters of high PSR region were observed in cortex of DN mouse kidneys. Abnormally high PSR regions (% area) that were detected by the threshold PSR were significantly increased in renal cortexes of DN mice. These regions progressively increased on aging and highly correlated with histological fibrosis measures, while the mean PSR values correlated much less.

Conclusion

Renal fibrosis in DN can be assessed by the quantitative magnetization transfer MRI and threshold analysis. This technique may be used as a novel imaging biomarker for DN and other renal diseases.
Revealing sub‐voxel motions of brain tissue using phase‐based amplified MRI (aMRI)
Authors: Terem Itamar , Ni Wendy W. , Goubran Maged , Rahimi Mahdi Salmani , Zaharchuk Greg , Yeom Kristen W. , Moseley Michael E. , Kurt Mehmet , Holdsworth Samantha J.
Published: May 2018

Purpose

Amplified magnetic resonance imaging (aMRI) was recently introduced as a new brain motion detection and visualization method. The original aMRI approach used a video‐processing algorithm, Eulerian video magnification (EVM), to amplify cardio‐ballistic motion in retrospectively cardiac‐gated MRI data. Here, we strive to improve aMRI by incorporating a phase‐based motion amplification algorithm.

Methods

Phase‐based aMRI was developed and tested for correct implementation and ability to amplify sub‐voxel motions using digital phantom simulations. The image quality of phase‐based aMRI was compared with EVM‐based aMRI in healthy volunteers at 3T, and its amplified motion characteristics were compared with phase‐contrast MRI. Data were also acquired on a patient with Chiari I malformation, and qualitative displacement maps were produced using free form deformation (FFD) of the aMRI output.

Results

Phantom simulations showed that phase‐based aMRI has a linear dependence of amplified displacement on true displacement. Amplification was independent of temporal frequency, varying phantom intensity, Rician noise, and partial volume effect. Phase‐based aMRI supported larger amplification factors than EVM‐based aMRI and was less sensitive to noise and artifacts. Abnormal biomechanics were seen on FFD maps of the Chiari I malformation patient.

Conclusion

Phase‐based aMRI might be used in the future for quantitative analysis of minute changes in brain motion and may reveal subtle physiological variations of the brain as a result of pathology using processing of the fundamental harmonic or by selectively varying temporal harmonics. Preliminary data shows the potential of phase‐based aMRI to qualitatively assess abnormal biomechanics in Chiari I malformation.