bluuebunny/crossref_metadata_2025 huggingface dataset:
The interplay between glioblastoma and microglia cells leads to endothelial cell monolayer dysfunction via the interleukin‐6‐induced JAK2/STAT3 pathway
Authors: Couto Marina , Coelho‐Santos Vanessa , Santos Liliana , Fontes‐Ribeiro Carlos , Silva Ana Paula , Gomes Célia M. F.
Published: April 2019

Glioblastoma multiforme (GBM) is the most common and aggressive primary brain tumor, with an average life expectancy of 12–15 months. GBM is highly infiltrated by microglial cells (MG) promoting tumor growth and invasiveness. Moreover, microglia activation and subsequent neuroinflammation seem to be involved in blood–brain barrier (BBB) dysfunction commonly observed in several central nervous system diseases, including brain tumors. Nevertheless, how the crosstalk between microglia and tumor cells interferes with BBB function is far from being clarified. Herein, we evaluated the effects of reciprocal interactions between MG and GBM cells in the barrier properties of brain endothelial cells (ECs), using an in vitro approach.

The exposure of ECs to the inflammatory microenvironment mediated by MG‐GBM crosstalk induced a decrease in the transendothelial electric resistance and an increase in permeability across the ECs (macromolecular flux of 4 kDa‐fluorescein isothiocyanate and 70 kDa‐Rhodamine B isothiocyanate–Dextran). These effects were accompanied by a downregulation of the intercellular junction proteins, β‐catenin and zonula occludens. Moreover, the dynamic interaction between microglia and tumor cells triggered the release of interleukin‐6 (IL‐6) by microglia and subsequent activation of the downstream Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathway. Interestingly, the depletion of IL‐6 or the blockade of the JAK/STAT3 signaling with AG490 were able to prevent the EC hyperpermeability. Overall, we demonstrated that IL‐6 released during MG‐GBM crosstalk leads to barrier dysfunction through the activation of the JAK/STAT3 pathway in ECs and downregulation of intercellular junction proteins. These results provide new insights into the mechanisms underlying the disruption of BBB permeability in GBM.
Osteogenic transdifferentiation of vascular smooth muscle cells isolated from spontaneously hypertensive rats and potential menaquinone‐4 inhibiting effect
Authors: Mandatori Domitilla , Pipino Caterina , Di Tomo Pamela , Schiavone Valeria , Ranieri Antonia , Pantalone Sara , Di Silvestre Sara , Di Pietrantonio Nadia , Ucci Mariangela , Palmerini Carola , Failli Paola , Di Pietro Natalia , Pandolfi Assunta
Published: April 2019

Vascular calcification (VC) is an active and cell‐mediated process that shares many common features with osteogenesis. Knowledge demonstrates that in the presence of risk factors, such as hypertension, vascular smooth muscle cells (vSMCs) lose their contractile phenotype and transdifferentiate into osteoblastic‐like cells, contributing to VC development. Recently, menaquinones (MKs), also known as Vitamin K2 family, has been revealed to play an important role in cardiovascular health by decreasing VC. However, the MKs' effects and mechanisms potentially involved in vSMCs osteoblastic transdifferentiation are still unknown. The aim of this study was to investigate the possible role of menaquinone‐4 (MK‐4), an isoform of MKs family, in the modulation of the vSMCs phenotype. To achieve this, vascular cells from spontaneously hypertensive rats (SHR) were used as an in vitro model of cell vascular dysfunction. vSMCs from Wistar Kyoto normotensive rats were used as control condition. The results showed that MK‐4 preserves the contractile phenotype both in control and SHR‐vSMCs through a γ‐glutamyl carboxylase‐dependent pathway, highlighting its capability to inhibit one of the mechanisms underlying VC process.

Therefore, MK‐4 may have an important role in the prevention of vascular dysfunction and atherosclerosis, encouraging further in‐depth studies to confirm its use as a natural food supplement.
Tetramethylpyrazine reduces the consequences of nitric oxide inhibition in pregnant rats
Authors: Gu Shengyi , Shen Huaxiang , Zhou Yun , Ni Jiaying , Zheng Tao , Mou Zhengqian , Hua Xiaolin
Published: April 2019

Pre‐eclampsia (PE) is closely associated with perinatal morbidity and mortality and we want to investigate tetramethylpyrazine (TMP)'s effects on PE. Pregnant Sprague–Dawley rats were randomly divided into five groups: normal pregnant (PC), PE, PE+TMP 20 mg/kg, PE+TMP 40 mg/kg, and PE+TMP 60 mg/kg group. The PE rat model was established via L‐NAME treatment. Systolic blood pressures (SBP) and urinary protein concentration were detected via the tail‐cuff method and CBB kit, respectively. mRNA levels of key genes were analyzed via quantitative PCR and protein levels of key genes were measured by ELISA or western blot. TMP decreased SBP and urinary protein concentration of PE rats. TMP inhibited L‐NAME‐induced decrease in pups alive ratio, pups weight, and the ratio of pups/placenta weight and reversed L‐NAME induced changes in placental histology, whereas it had little effect on placental weight. Urinary nephrin and podocin expressions were enhanced and serum placental growth factor level was decreased in PE rats, whereas TMP inhibited the above phenomena. TMP suppressed L‐NAME‐induced sFlt‐1 upregulation in serums and kidneys of PE rats, whereas it downregulated IL‐6 and MCP‐1 expression in PE rats' serums, placentas and kidneys. TMP also suppressed the increase in placental sFlt‐1 and vascular endothelial growth factor level caused by L‐NAME. In addition, TMP inhibited CHOP and GRP78 expressions and decreased the ratio of p‐elF2α/elF2α in PE rats. TMP attenuated the consequences of NO inhibition in pregnant rats.
Effect of weight loss on the estimated glomerular filtration rates of obese patients at risk of chronic kidney disease: the RIGOR‐TMU study
Authors: Lin Yen‐Chung , Lai Yi‐Jen , Lin Yi‐Chun , Peng Chiung‐Chi , Chen Kuan‐Chou , Chuang Ming‐Tsang , Wu Mai‐Szu , Chang Tzu‐Hao
Published: April 2019

Background

Weight‐reduction therapies, including bariatric surgery (BS), are standard treatments for severely obese patients with type 2 diabetes; however, the outcomes of these therapies are inconclusive for obese patients with chronic kidney disease (CKD). This study aimed to investigate the effects of BS or non‐surgical interventions on the estimated glomerular filtration rate (eGFR) and to determine whether BS can be recommended for renal function preservation based on body mass index (BMI) and eGFR changes in obese patients with CKD.

Methods

This study used data from the weight Reduction Intervention on GFR in Obese Patients with Renal Impairment‐Taipei Medical University (TMU) study, which was a large, long‐term, propensity score‐matched cohort study based on clinical data from patients who registered at weight‐reduction centres at TMU and its affiliated hospitals from 2008 to 2016. The patients were stratified according to whether they had undergone BS and into the mild, moderate, and high CKD risk groups using the Kidney Disease: Improving Global Outcomes guidelines. The primary outcome was the eGFR calculated using the Taiwan Chronic Kidney Disease‐Epidemiology Collaboration equation. Cox regression models were used to determine hazard ratios (HRs) for eGFR decreases ≥25%.

Results

A total of 4332 obese patients were enrolled in this study. After propensity score matching, 1620 patients, including 60.2% women, with a mean age of 36.5 (9.9) years were divided into BS or non‐surgery groups (n = 810 per group). The overall mean eGFRs increased by 4.4 (14) mL/min·1.73 m2 and decreased by 6.4 (16.0) mL/min·1.73 m2 in the BS and non‐surgery groups, respectively. The decrease in BMI in the BS and non‐surgery groups were 2.5 and 1.3 kg/m2, respectively. In the moderate/high CKD risk BS group, a significant correlation was evident between an increased eGFR and a reduced BMI (Spearman's correlation −0.229, P < 0.001). The Cox regression analysis showed that the BS group had a significantly lower risk of an eGFR decline ≥25% at 12 months [adjusted HR (aHR) 0.47, P = 0.03). After BS, obese patients with hypertension or albuminuria had significantly lower risks of eGFR declines ≥25% (aHR 0.37, P = 0.02 and aHR 0.13, P = 0.0018, respectively).

Conclusions

Bariatric surgery was associated with eGFR preservation in all obese patients and, particularly, in those with moderate‐to‐high CKD risks. A longer term outcome study is warranted to determine the benefits of BS for CKD patients.
Synthesis of Novel Symmetric Porphyrin Schiff Base Dimers by Solid–Liquid Reaction Methodology
Authors: Yaseen Muhammad , Farooq Zahid , Mahmood Mian H. R. , Ahmad Sheikh Asrar , Nazir Shahbaz , Anjum Khalid Mahmood , Naqvi Syed Ali Raza
Published: April 2019

A new convenient solid–liquid condensation reaction procedure for the synthesis of novel asymmetric and symmetricmeso‐tetraarylporphyrin and metalloporphyrin Schiff bases is reported. The condensation reaction between β‐formyl porphyrin or metalloporphyrins and aromatic amines was carried out at solid–liquid interface by using neutral alumina powder as a solid support for β‐formyl porphyrin or metalloporphyrins and absolute ethanol as the carrier solvent for aromatic amines. Six different asymmetric porphyrin/metalloporphyrin Schiff bases were synthesizedviasolid–liquid interface reaction methodology. The same solid–liquid synthetic methodology was applied for the synthesis of six novel symmetric Schiff base porphyrin/metalloporphyrin dimers. The comparison of UV–visible spectra of porphyrin Schiff base monomers and dimers revealed that some degree of electronic perturbation has occurred upon dimerization as the Soret bands of the monomers underwent peak broadening along with red shifts. Column chromatography and crystallization were used to purify the compounds. Fourier transform infrared, UV–visible, elemental analysis,1H NMR, and mass spectrometry were used to characterize the newly synthesized compounds.
Implementation of a new separation method to produce qualitatively improved 64Cu
Authors: van der Meulen Nicholas P. , Hasler Roger , Blanc Alain , Farkas Renata , Benešová Martina , Talip Zeynep , Müller Cristina , Schibli Roger
Published: April 2019

Background

64Cu (T1/2 = 12.7 h) is an important radionuclide for diagnostic purposes and used for positron emission tomography (PET). A previous method utilized at Paul Scherrer Institute (PSI) proved to be unreliable and, while a method using anion exchange chromatography is a popular choice worldwide, it was felt a different approach was required to obtain a robust chemical separation method.

Methods

Enriched 64Ni targets were created by electroplating on gold foil. The targets were irradiated with protons degraded to approximately 11 MeV at PSI's Injector 2 72 MeV research cyclotron and subsequently dissolved in HCl. The resultant solution was loaded onto AG MP‐50 cation exchange resin and the 64Cu separated from its target material and radiocobalt impurities, produced as part of the irradiation process, using various specific mixtures of HCl/acetone solution. The eluted product was evaporated and picked up in dilute HCl (0.05 M). The chemical purity of 64Cu was determined by radiolabeling experiments at the highest possible molar activities.

Results

Reproducible results were obtained, yielding 3.6 to 8.3 GBq 64Cu of high radionuclidic and radiochemical purity. The product was labeled to NODAGA‐RGD, achieved at up to 500 MBq/nmol, indicating the high chemical purity. In a proof‐of‐concept in vivo study, 64Cu‐NODAGA‐RGD was used for PET imaging of a tumor‐bearing mouse.

Conclusion

The chemical separation devised to produce high‐quality 64Cu proved to be robust and reproducible. The concept can be used at medical cyclotrons utilizing a solid target station, such that 64Cu can be used at hospitals for PET imaging.
Infrared and Raman spectra of lignin substructures: Coniferyl alcohol, abietin, and coniferyl aldehyde
Authors: Bock Peter , Gierlinger Notburga
Published: April 2019

Anatomical and chemical information can be linked by Raman imaging. Behind every pixel of the image is a Raman spectrum, which contains all the information as a molecular fingerprint. Yet to understand the spectra, the bands have to be assigned to components and their molecular structures. Although the lignin distribution is easily tracked in plant tissues, the assignment of the spectra is not good enough to allow in‐depth analysis of the composition. Assignments of three lignin model compounds were derived from polarization measurements and quantum‐chemical computations. Raman spectra of coniferyl alcohol crystals showed orientation dependence, which helped in band assignment. Abietin showed a Raman spectrum that was very similar to the spectrum of coniferyl alcohol, whereas its IR spectrum was very different due to bands of the sugar moiety. The Raman spectrum of coniferyl aldehyde is affected by the crystal order of molecules. All three compounds show much stronger band intensities than unconjugated single aromatic rings, indicating that the bulk of the lignin structure has significantly reduced contribution to Raman band intensities. Therefore, it is possible to highlight certain structures of lignin with Raman spectroscopy, because low amounts of a compound do not necessarily mean weak features in the spectrum.
Building hot spots in different plasmonic nanoparticles from a cruciform bifunctional dipyridine anthracene
Authors: Imbarack Elizabeth , Sánchez‐González Rodrigo , Soto Juan Pablo , Leyton Patricio , López‐Tocón Isabel , Soto Juan , Sanchez‐Cortes Santiago , Otero Juan Carlos , Campos‐Vallette Marcelo
Published: April 2019

In this work, the adsorption of a type of cruciform system integrated by an anthracene central part and two side chains with a pyridine‐vinyl structure (DPAC) was studied on plasmonic nanoparticles of silver and gold. The adsorption was investigated by surface‐enhanced Raman scattering, which reveals very valuable information about both the interaction mechanism and the molecular orientation. The highest Raman enhancement was measured on Ag nanostars due to the combination of gaps and tips in these nanostructures. The changes observed in the surface‐enhanced Raman scattering spectra indicate that the adsorption of DPAC on the metal is bifunctional in the case of Ag and Au nanoparticles. Considering that the Raman signals enhancement is several orders of magnitude higher in gaps in relation to regions out of these areas, it is estimated that the enhancement ability of DPAC in Ag nanostars is so high that it allows the detection of a concentration close to pM.
Combined microfluidics–confocal Raman microscopy platform for studying enhanced oil recovery mechanisms
Authors: Gao Jun , Nair Sachin , Duits Michel H.G. , Otto Cees , Mugele Frieder
Published: April 2019

To study the mechanism of enhanced oil recovery, it is important to characterize the three‐dimensional spatial distribution of various chemical species, especially water and oil, and their evolution during the course of water flooding. For example, visualizing the (selective) removal of oil from clay or silica substrates by low salinity water can yield important insights. Here, we present a platform that uses a microfluidic device (to represent water flooding at the pore scale) in combination with confocal Raman microscopy. Distributions of oil, water, and minerals are resolved at submicrometer resolution upon flooding water with changing composition. Using glass and gibbsite to mimic sandstone and clay, and water containing divalent cations (Ca2+), we find that oil containing a fatty acid preferentially adsorbs on the gibbsite. Removal of the divalent cations leads to release of the oil droplet. This finding is consistent with the multiple ion exchange mechanism and underlines that the presence of clay is important for low salinity enhanced oil recovery. We expect that our platform will pave the road towards systematic screening of water flood compositions in more complex systems.
Effect of current density on micro‐arc oxidation of Q235 steel and corrosion resistance in liquid Pb‐Bi
Authors: Zhu Qiang , He Ning , Zhang Yanchao , Lei Yucheng
Published: April 2019

An attempt has been made to improve the corrosion resistance in liquid Pb‐Bi by micro‐arc oxidation (MAO), and the effects under different current densities on the corrosion resistance of the coatings were discussed. Scanning electron microscope, energy dispersive spectrometer, and X‐ray diffraction were used to analyze the surface morphology and phase constituents of the MAO coatings produced under different current densities. The corrosion resistance of the coatings was evaluated by studying the element changes and morphology evolution. The results show that the compactness of the ceramic coating decreases with the current density increasing. In contrast to the performance of matrix metal, the ceramic coating exhibited a much better corrosion resistance in liquid Pb‐Bi. Moreover, the ceramic coating produced under current density of 10 A/dm
2 shows the best corrosion resistance.
New surfactants N‐alkyl‐N,N‐dimethyl‐N‐(3‐thienylmethylene)ammonium bromides: Preparation and anticorrosion evaluation
Authors: Chen Ziyu , Xiaohui Jiang , Cheng Zhengjun , Liao Yunwen , Pu Qiang , Duan Ming
Published: April 2019

A new series of N‐alkyl‐N,N‐dimethyl‐N‐(3‐thienylmethylene)ammonium bromides (designated as NTA‐n, n = 8, 10, 12, 14, and 16) were synthesized. The electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization showed that NTA‐n could protect availably X70 steel from attack of HCl with an inhibition efficiency of about 95%. And the inhibition ability follows the following sequence: NTA‐8 < NTA‐10 < NTA‐12 < NTA‐14 < NTA‐16, suggesting that prolonging alkyl chain may enhance the inhibition capacity of the molecules. Theoretical investigation backs up well the experiment results. The correlation of theoretical calculation with the experiment results illustrated clearly double logarithmic relations between the corrosion current and the computed quantum chemical parameters such as the highest occupied molecular orbital energy (), energy gap (ΔE), molecular volume (
ν), electronegativity (
χ), the total energy of iron crystal with the adsorbed inhibitor molecule ), the interaction energy of Fe (1 0 0) surface and inhibitor molecules (), while an equation resembling Hammet relation was existed between the corrosion currents and the fraction of electrons transfer (ΔN). These linear correlations suggest the relation of the inhibitor structure with its inhibition activity: long alkyl chain and electron donating groups in NTA‐n will enhance the corrosion efficiency.
Corrosion protection of epoxy coatings containing ZSM‐5 zeolites on Mg–Li alloys
Authors: Wang Yanli , Yan Dashuai , Zhu Yanhao , Liu Jialiang , Song Dalei , Chen Liman , Zhang Tao , Cheng Kui , Zhang Meng , Wang Jun
Published: April 2019

The epoxy composite coatings are developing towards nontoxic and environmentally friendly in the field of corrosion protection. In this study, ZSM‐5 zeolites were chosen as fillers and added to the epoxy coatings on the Mg–Li alloy surface. The effect of ZSM‐5 zeolites on the corrosion properties of epoxy coating was investigated. The results show that the epoxy coating doped with ZSM‐5 zeolites can improve the corrosion protection of the substrate. In particular, the epoxy coating loaded with 0.5% ZSM‐5 zeolites provides enough protection of the alloy against corrosion.
Effect of laser repairing on corrosion behaviour of metal–inert gas welding joint of 7N01 aluminium alloy
Authors: Huang Shuang , Xu Lidong , Chen Hui , Che Xiaoli , Wang Yirong , Yang Xiaoyi
Published: April 2019

The heat affected zone (HAZ) on the metal–inert gas (MIG) welding joint of 7N01 aluminium alloy was repaired by multipass narrow gap laser welding. The Y–X direction precracked three‐point bending sample was used in the alternate immersion test. The morphology of specimen surfaces demonstrated that the exfoliation corrosion in the HAZ after laser repair (HAZa) was more serious than that before laser repair (HAZb). The electrochemical impedance spectroscopy after different immersion corrosion time indicated that the HAZa and HAZb had similar corrosion potentials. However, the pitting corrosion resistance of HAZa was lower than that of HAZb at the beginning of exfoliation corrosion. The stress corrosion crack (SCC) of 7N01P‐T4 aluminium alloy displayed a multicrack source and an intergranular crack propagated along the rolling grain boundary under the test condition. An unusual method was taken to measure the length of SCC. The results showed that laser repairing did not weaken the stress corrosion resistance of the original joint.
Corrosion behavior of porous magnesium coated by plasma electrolytic oxidation in simulated body fluid
Authors: Ghasemi Alireza , Kamrani Sepideh , Hübler Daniela , Fleck Claudia
Published: April 2019

Porous magnesium has a great potential to be used as degradable bone scaffolds. In this study, porous magnesium with 35% percolating porosity has been successfully fabricated through powder metallurgy route utilizing space holders. The intrinsic mechanical properties of the porous magnesium were measured by nanoindentation testing and analyzed with the Oliver–Pharr method. Afterward, a ceramic coating on the surface of the porous magnesium was performed by plasma electrolytic oxidation (PEO) treatment in a silicate‐based solution. The morphology and composition results of the PEO coatings indicated that it is possible to apply a homogenous and adhesive ceramic coating layer on all free surface of the porous magnesium through PEO method. The protective performance of the PEO coatings was evaluated using by potentiodynamic polarization and electrochemical impedance spectroscopy tests in simulated body fluid. The results revealed the PEO coating significantly improves biocorrosion resistance of the porous magnesium. Therefore, it can be used as an effective method to control the degradation rate of porous magnesium implants in the human body.
Analysis of Brownian Dynamics and Molecular Dynamics Data of Unentangled Polymer Melts Using Proper Orthogonal Decomposition
Authors: Wong Chi Pui Jeremy , Choi Phillip
Published: April 2019

A non‐linear Brownian dynamics (BD) model based upon the Rouse model is developed for unentangled polymer melts. The essence of the model is that it includes an equilibrium spring length b, a non‐linear force term that is not present in the equation of motion of the Rouse model. The equation of motion is solved numerically with the technique of proper orthogonal decomposition (POD) to obtain the dynamics information. To illustrate that the BD model can be readily implemented on polymers with different molecular structures, it is applied to polyethylene with linear, ring, and star structures. For comparison purpose, the corresponding molecular dynamics (MD) simulation is also carried out on molecules with the same sizes (N = 30–73). To characterize the dynamics, time correlation functions of the end‐to‐end vector, the m‐to‐n vector, and the arm vector of the linear, ring, and star polyethylene are determined respectively. It is found that the longest relaxation times (τ1s), the relaxation times of the vectors (τv
s), as well as zero‐shear viscosity (η0s) obtained from the BD and MD simulations agree well with each other. The time correlation functions can be reasonably described using the eigenmodes.
Dissent, sabotage, and leader behaviour in contests: Evidence from European football
Authors: Kempa Karol , Rusch Hannes
Published: April 2019

This paper provides an empirical investigation of misconducts in contests based on data from European football. We extend previous studies by differentiating between dissents with the referee and misconducts directly aimed at sabotaging the competitor. We find that sabotage is more likely committed by teams with lower ability. Dissent is more likely to be shown by teams lagging behind in score and by away teams. We further find that captains engage more in sabotage during important matches and challenge referees' decisions immediately after sanctions of teammates. Finally, we also observe a deterrence effect of sanctions on all types of misconduct.
Study and analysis of a two‐dimensional nonconservative fractional order aerosol transport equation
Authors: Singh Anup , Chopra Manish , Das Subir
Published: April 2019

The shifted Legendre collocation method is used to solve the two‐dimensional fractional order aerosol equation with initial and boundary conditions. The solution profile of the equation is presented graphically for different cases. The important feature of the article is graphical exhibitions of the effect of the size of the aerosol particles and also the temporal derivative on the solution profile. The salient feature of the article is the demonstration of lower variation of mass concentration with the change in time level in fractional order systems than that in integer order system. A drive has been taken towards the tabular and pictorial presentations of a comparison of the numerical solution of our proposed method with an analytical solution of an existing problem through error analysis which conforms super‐linearly convergence rate of the proposed method to validate its efficiency and effectiveness.
Synthesis of new cyano‐substituted analogues of Tröger's bases from bromo‐derivatives. A stereochemical dependence of long‐range (nJHH, n = 4, 5, and 6) proton–proton and proton–carbon (nJCH, n = 1, 2, 3, 4, and 5) coupling constants of these compounds
Authors: Dusso Diego , Ramirez Cristina , Parise Alejandro , Lanza P. , Vera D. Mariano , Chesta Carlos , Moyano E. Laura , Akhmedov Novruz G.
Published: April 2019

A free‐catalyst microwave‐assisted cyanation of brominated Tröger's base derivatives (2a‐f) is reported. The procedure is simple, efficient, and clean affording the nitrile compounds (3a‐e, I) in very good yields. Complete assignment of 1H and 13C chemical shifts of 2a‐f, I and 3a‐d, I was achieved using gradient selected 1D nuclear magnetic resonance (NMR) techniques (1D zTOCSY, PSYCHE, DPFGSE NOE, and DEPT), homonuclear 2D NMR techniques (gCOSY and zTOCSY), and heteronuclear 2D NMR techniques (gHSQCAD/or pure‐shift gHSQCAD, gHMBCAD, bsHSQCNOESY, and gHSQCAD‐TOCSY) with adiabatic pulses. Determination of the long‐range proton–proton coupling constants nJHH (n = 4, 5, 6) was accomplished by simultaneous irradiation of two protons at appropriate power levels. In turn, determined coupling constants were tested by an iterative simulation program by calculating the 1H NMR spectrum and comparing it to the experimental spectrum. The excitation‐sculptured indirect‐detection experiment (EXSIDE) and 1H‐15N CIGARAD‐HMBC (constant time inverse‐detection gradient accordion rescaled heteronuclear multiple bond correlation) were applied for determination of long‐range carbon–proton coupling constants nJCH (n = 2, 3, and 4) and for assignment of 15N chemical shift at natural abundance, respectively. DFT/B3LYP optimization studies were performed in order to determine the geometry of 2c using 6‐31G(d,p), 6‐311G(d,p), and 6–311 + G(d,p) basis sets. For calculation of 1H and 13C chemical shifts, nJHH (n = 2, 3, 4, 5, and 6), and nJCH (n = 1, 2, 3, and 4) coupling constants, the GIAO method was employed at the B3LYP/6‐31G(d,p), B3LYP/6‐31+G(d,p), B3LYP/6‐311+G(d,p), B3LYP/6‐311++G(2d,2p), B3LYP/cc‐pVTZ), and B3LYP/aug‐cc‐pVTZ) levels of theory. For the first time, a stereochemical dependence magnitude of the long‐range nJHH (n = 4, 5, and 6) and nJCH (n = 1, 2, 3, 4, and 5) have been found in bromo‐substituted analogues of Tröger's bases.
Molecular effects on spermatozoa of Mytilus galloprovincialisexposed to hyposaline conditions
Authors: Lettieri Gennaro , Maione Martina , Ranauda Maria Antonietta , Mele Elena , Piscopo Marina
Published: April 2019

Salinity represents a critical environmental and an ecological factor in the reproduction of marine species. As global climate changes and anthropogenic factors affect salinity, in this study, we have analyzed the responses of Mytilus galloprovincialis spermatozoa to hyposaline stress. We exposed mussels, in laboratory tanks, for 24 hr at 18°C to control (35.9 psu) and three hyposaline (17.1, 22.6, and 26.2 psu) conditions, and evaluated the expression of sperm hsp70 and protamine‐like proteins genes. Further we analyzed the electrophoretic pattern, the DNA binding and the release from sperm nuclei of protamine‐like proteins. For all experimental approaches used, the results obtained at 17.1 psu condition were very similar to those obtained in the control condition, while alterations were always recorded at 22.6 and 26.2 psu conditions. Particularly, at 22.6 and 26.2 psu, was observed: 42.5‐ and 17.1‐fold increase in hsp70 expression, respectively, and hypoexpression of PL‐II/PLIV protamine‐like proteins genes. Further, electrophoretic mobility shift assays and salt‐induced release of nuclear proteins from sperm nuclei, revealed alterations in the PL proteins/DNA binding, in these two hyposaline conditions. The similarity between the results obtained in control and in the more severe hyposaline condition (17.1 psu) could indicate a phenomenon of fertility preservation strategy due to gamete plasticity.
Parameterization of Models for Vapor Solubility in Semicrystalline Polyethylene
Authors: Savatsky Bruce J. , Moebus Joseph A. , Greenhalgh Brian. R.
Published: April 2019

This paper extends the previous article by the authors on the solubility of hydrocarbon vapors in semicrystalline polyethylenes produced in the gas phase process. That work demonstrates a computational model for solubility based on an activity coefficient modification of the Sako–Wu–Prausnitz equation of state. In that work, by fitting a key parameter, one related to the constraint of tie chains on polymer fluid behavior, to a single isopentane solubility isotherm, accurate predictions of hydrocarbon solubility in polymer granules over a range of temperature, pressure, and composition are reported. In the present work, additional experimental solubility data are reported, an error in the authors' previous article is corrected, and a useful parameterization method that improves the predictive capabilities of the model is demonstrated. By using the model to predict much of the authors' own experimental data, as well as that published by others in the field, it is demonstrated how the proposed parameterization method allows for accurate predictions using a limited amount of experimental measurements.
The influence of nebivolol on the activity of BRL 37344 — the β3‐adrenergic receptor agonist, in the animal model of detrusor overactivity
Authors: Wróbel Andrzej , Miziak Barbara , Bańczerowska‐Górska Małgorzata , Szopa Aleksandra , Serefko Anna , Stangel‐Wójcikiewicz Klaudia , Czuczwar Piotr , Laskowska Marzena , Wlaźlak Edyta , Dudka Jarosław , Poleszak Ewa
Published: April 2019

Aims

The cardiotoxic effects of antimuscarinics constitute a significant restriction in their application in elderly people. Overactive bladder syndrome pharmacotherapy using compounds with cardioprotective properties would seem an ideal solution. The main goal of the study was to assess the impacts of nebivolol (NEB) on the activity of BRL 37344 — β3‐adrenergic receptor (β3AR) agonist, in the animal model of detrusor overactivity. As both these substances can impact on the cardiovascular system, their effect on the parameters of this system and diuresis was also examined.

Methods

Retinyl acetate (RA; 0.75%) solution was used to induce detrusor overactivity in female Wistar rats. BRL and/or NEB were administered intra‐arterially during cystometry in a single dose (2.5 or 5, 0.05 or 0.1 mg/kg, respectively). In addition, a 24 hours measurement of heart rate, blood pressure, and urine production was carried out.

Results

NEB (0.05 mg/kg) and BRL (2.5 mg/kg) monotherapy proved to have no influence on the cystometric parameters of animals with RA‐induced detrusor overactivity. NEB at 0.1 mg/kg resulted in a drop in the detrusor overactivity index, similarly to BRL at 5 mg/kg. Coadministration of NEB and BRL, both at ineffective doses, decreased the detrusor overactivity index and ameliorated the nonvoiding contractions. β3AR stimulation proved to induce tachycardia and hypertension. NEB at 0.05 mg/kg proved to ameliorate detrusor overactivity and have preventive properties against adverse cardiovascular effects of the β3AR agonist.

Conclusions

The combined application of the β3AR agonist and NEB may improve detrusor overactivity without affecting the heart rate, blood pressure, and urine production.
More is less? The volunteer stewardship framework and models
Authors: Brudney Jeffrey L. , Meijs Lucas C. P. M. , van Overbeeke Philine S. M.
Published: April 2019

Scholars have devoted substantial attention to developing conditional models of volunteer administration and management, but no consensus surrounds the criteria underlying the different models or the rationale. The literature reveals a welter of possibilities but no clear choice. This study conceives the primary managerial challenges as securing access to and guiding volunteer energy into productive volunteering, and the volunteer administrator as the central actor in this process. Based on how volunteers are accessed and guided in their roles, we develop the Volunteer Stewardship Framework, which distinguishes volunteer administration according to two key dimensions: organizational access to volunteer energy (private resource vs. common pool) and guidance of volunteers (unitary vs. shared). Results of a survey of volunteer administration practitioners in the Netherlands show that respondents working under the four models emanating from the Framework recognize different elements of volunteer administration as “Very Important.”
Effect of lorcaserin on weight reduction in persons with obstructive sleep apnea (OSA): a combined subgroup analysis from three randomized, controlled clinical trials
Authors: Fujioka K. , Perdomo C. , Malhotra M.
Published: April 2019

Study objectives

To evaluate weight loss with lorcaserin in persons with obstructive sleep apnea (OSA).

Methods

This retrospective analysis evaluated weight loss of lorcaserin (10 mg twice daily) versus placebo in persons with obesity or overweight persons with OSA from a pooled database of three randomized, controlled trials. Primary end points were reductions in the baseline body weight of ≥5% and ≥10% at year 1 and overall weight change at year 1. Changes in heart rate and blood pressure were also evaluated.

Results

A total of 336 persons with OSA were identified in the overall pooled population (N = 6,636). At year 1, more patients receiving lorcaserin lost ≥5% (47.2% lorcaserin vs. 25.6% placebo; p < 0.0001) and 10% (22.2% lorcaserin vs. 13.1% placebo; p < 0.0354) of their baseline body weight. Weight loss at year 1 was 6.4 kg versus 3.5 kg in the lorcaserin and placebo groups, respectively (p < 0.0001). Similar results were observed for change in blood pressure and heart rate, with responders having larger benefits. Weight loss was similar between persons with and without OSA.

Conclusions

In this retrospective analysis, persons with OSA showed significant and meaningful weight loss, blood pressure and heart rate reductions in patients treated with lorcaserin versus placebo. Persons with OSA lost just as much weight as those without OSA. Health care providers can expect persons with OSA to lose weight by diet, exercise and the weight loss medication lorcaserin comparable with persons without OSA. Further prospective research is warranted to evaluate impact of weight loss on OSA and overall outcomes for patients.
School Starting Age and Cognitive Development
Authors: Dhuey Elizabeth , Figlio David , Karbownik Krzysztof , Roth Jeffrey
Published: April 2019

We present evidence of a positive relationship between school starting age and children's cognitive development from ages 6 to 18 using a fuzzy regression discontinuity design and large‐scale population‐level birth and school data from the state of Florida. We estimate effects of being old for grade (being born in September vs. August) that are remarkably stable—always around 0.2 SD difference in test scores—across a wide range of heterogeneous groups, based on maternal education, poverty at birth, race/ethnicity, birth weight, gestational age, and school quality. While the September‐August difference in kindergarten readiness is dramatically different by subgroup, by the time students take their first exams, the heterogeneity in estimated effects on test scores effectively disappears. We do, however, find significant heterogeneity in other outcome measures such as disability status and middle and high school course selections. We also document substantial variation in compensatory behaviors targeted towards young‐for‐grade children. While the more affluent families tend to redshirt their children, young‐for‐grade children from less affluent families are more likely to be retained in grades prior to testing. School district practices regarding retention and redshirting are correlated with improved outcomes for the groups less likely to use those remediation approaches (i.e., retention in the case of more affluent families and redshirting in the case of less affluent families.) Finally, we find that very few school policies or practices mitigate the test score advantage of September‐born children.
Money Talks: The Environmental Impact of China's Green Credit Policy
Authors: Sun Junxiu , Wang Feng , Yin Haitao , Zhang Bing
Published: April 2019

This study examines the impact of China's green credit policy on the environment. In particular, we consider an initiative that requires all banks to base their loan decisions on corporate environmental performance. This is an important issue since it is globally gaining popularity to leverage bank loans as an avenue to enforce corporate environmental responsibility. Moreover, there are only a handful of empirical investigations in relation to the impacts of credit constraint on corporate environmental behaviors and strategies. This research also provides useful insights on how to enhance environmental regulation enforcement, using the Environmental Protection Bureau in partnership with local banks to exert a creditable threat of financial constraint on unfavorable environmental outcomes. Using the synthetic control method and difference‐in‐differences analysis, we find that this policy has significantly motivated firms, particularly those firms with a higher dependence on external financing, to reduce water pollution. We further discover that the policy compels firms to favor pollution prevention at the source instead of end‐of‐pipe treatments, since the policy imposes a long‐term credit constraint on pollution.
Preparation of long‐chain branched poly(ethylene terephthalate): Molecular entanglement structure and toughening mechanism
Authors: Liu Juan , Ye Lin , Zhao Xiaowen
Published: April 2019

Poly(ethylene terephthalate) (PET) was long‐chain branched (LCB) by ring‐opening reaction with both pyromellitic dianhydride and tetrahydrophthalic acid diglycidyl ester as chain extenders through reactive melt processing. It was found that with the increase of chain extenders dosage, the intrinsic viscosity of PET increased and melt index decreased greatly, while both the tensile strength and impact strength of PET were remarkably improved. The elastic modulus (G′) and viscous modulus (G″) were enhanced by chain branching. Compared with PET, the complex viscosities of LCB‐PET were much higher at full frequency range, and obvious shear thinning was presented. The Cole–Cole curve deviated from the semicircular shape and the curve end was inclined to upward in high viscosity region, indicating the formation of the multiple hierarchical structures. The molecular weight of the branch (MB) was much greater than critical entanglement molecular weight (M
e), which essentially confirmed the existence of LCB structure and fairly strong molecular entanglement in the LCB‐PET molecular chain. When subjected to external force, the entanglement point, acting as physical crosslinking point between the molecules, was in favor of increasing the molecular interaction, reducing the molecular slippage, and bearing a large deformation. POLYM. ENG. SCI., 59:1190–1198 2019. © 2019 Society of Plastics Engineers
Feasibility, Validity, and Responsiveness of Self‐Report and Objective Measures of Physical Activity in Patients With Chronic Pain
Authors: Stevens Matthew L. , Lin Chung‐Wei C. , van der Ploeg Hidde P. , De Sousa Maria , Castle Jessica , Nicholas Michael K. , Maher Chris G.
Published: April 2019

Background

Accurate tools for measuring physical activity are important for monitoring patients with chronic pain. However, these tools have not been properly validated in this population.

Objective

To determine the suitability of two physical activity measures for use in chronic pain populations.

Design

Longitudinal observational study.

Setting

Pain Management and Research Centre.

Participants

Sixty‐four patients presenting to the Pain Management and Research Centre with chronic pain.

Methods

Participants underwent a 3‐week pain management program that included cognitive behavioral strategies, education, and multiple exercises sessions per day. Physical activity was measured by the Active Australia Survey and the Actigraph GT3X at the start and end of the program. Feasibility of the physical activity measures was assessed. Criterion validity and responsiveness between the measures was compared. Correlation of physical activity with self‐rated global rating of change (GROC) scales in health were calculated.

Main Outcome Measurements

Minutes per day spent in low, moderate, and vigorous physical activity; global rating of change.

Results

Fifty‐two percent (n = 33) and 78% (n = 50) of participants had valid Actigraph and Active Australia data, respectively, for both time points. For criterion validity and responsiveness correlations varied (rho = −.12‐.52). All correlations between physical activity measures and GROC were small or negligible (rho ≤ .18).

Conclusion

Feasibility of the Actigraph was poor compared to the Active Australia Survey. The criterion validity and responsiveness of the Active Australia Survey to the Actigraph was inconsistent and the relationship of both these measures to clinical outcomes was poor. However, limitations due to missing data mean that further research is required.

Level of Evidence

III
Preparation and characterization of starch composites with cellulose nanofibers obtained by plasma treatment and ultrasonication
Authors: Fazeli Mahyar , Simão Renata Antoun
Published: April 2019

The cellulose nanofibers (CNF) are novelly extracted via air plasma treatment combined with the ultrasonication procedure. This study prepares and characterizes the starch‐based biocomposites reinforced by CNF within the glycerol plasticized matrix. The application of starch‐based polymers is improved with fabricating a biocomposite of thermoplastic starch (TPS) as matrix and the CNF as reinforcement. After modifying the surface of the cellulose fibers (CF) by air plasma treatment, CNFs are extracted by using an ultrasonic bath. The CNF are studied using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy. The TPS/CNF composites are prepared using the high‐friction and hot‐compression procedure. Tensile test results and SEM images of the fracture surfaces show significant improvement of adhesion between CNF and TPS matrix compared to composites reinforced by neat CF. The thermogravimetric analysis shows a considerable decompositionat approximately 270–340°C.
Utilizing surface modification in plasma‐enhanced cyclic etching of tantalum nitride to surpass lithographic limits
Authors: Marchack Nathan , Hernandez Keith , Walusiak Benjamin , Innocent‐Dolor Jon‐l , Engelmann Sebastian
Published: April 2019

Pitch subdivision of tantalum nitride (TaN) lines is demonstrated across a 200 mm wafer using a cyclic quasi‐atomic layer etch process in an inductively coupled plasma reactor. Chlorine (Cl2) and hydrogen (H
2) chemistries are introduced sequentially to an argon plasma in discrete steps to etch the TaN film. The starting lithographic pattern with critical dimension (CD) of approximately 82 nm and pitch of 200 nm thus yields lines of approximately 40 nm CD and 100 nm pitch with minimal line edge roughness increase. We identify a synergistic effect between H
2‐exposed TaN and Cl
2 plasma as contributing to this result, as well as a potential link to surface oxidation. Optical emission spectroscopy analysis of the plasma discharge is used to characterize reactive species densities and explain the observed changes in profile.
SiO2 microstructure evolution during plasma deposition analyzed via ellipsometric porosimetry
Authors: Buschhaus Rahel , von Keudell  Achim
Published: April 2019

The evolution of microstructures, deposited from hexamethyldisiloxane (HMDSO) and oxygen gas mixtures by two different low pressure plasma sources, namely an inductively coupled plasma (ICP process) at 3 Pa and a microwave plasma (MW process) at 100 Pa, is evaluated and compared. The microstructure is monitored using ellipsometric porosimetry (EP) applying three different solvent molecules (water, ethanol, and toluene) to probe the different adsorption and absorption mechanisms as well as the pore sizes. Both plasma processes are adjusted so that an equivalent oxygen atom contribution to the growth flux is established and that an equivalent specific energy per molecule is dissipated in the process. The major difference is the partial pressure of the HMDSO precursor molecules, which is 0.04 Pa in the ICP process and 1 Pa in the MW process. The porosimetry analysis indicates that the films originating from the MW process are more porous than those from the ICP process. The pore sizes are typically in the range of 0.3 nm for films deposited from both plasma processes. This is explained by assuming that the gas phase polymerization in the MW process is much stronger due to the higher HMDSO partial pressure and, therefore, the films are deposited from larger HMDSO fragments in the MW process compared with smaller HMDSO fragments in the ICP process. This difference in the main growth species becomes visible in the different microstructures. Consequently, a plasma process using smaller precursor partial pressures seems to be optimal.
Mortality in infants with bronchopulmonary dysplasia: Data from cardiac catheterization
Authors: Steurer Martina A. , Nawaytou Hythem , Guslits Elyssa , Colglazier Elizabeth , Teitel David , Fineman Jeffrey R. , Keller Roberta L.
Published: April 2019

Rationale

Pulmonary hypertension (PH) is relatively common in infants with severe bronchopulmonary dysplasia (BPD), however, hemodynamic data and factors associated with mortality in this patient group are sparsely described in the literature.

Objectives

To characterize the hemodynamics of former preterm infants with BPD and PH, as measured at cardiac catheterization, and to identify respiratory and cardiovascular predictors of mortality.

Methods

Single‐center, retrospective cohort study, including, 30 patients born at less than 32‐week gestational age (GA), who had an oxygen requirement at 36 weeks postmenstrual age and underwent cardiac catheterization between July 2014 and December 2017.

Results

Median GA at birth was 25 5/7 weeks (interquartile range [IQR], 24 4/7‐26 6/7 weeks). Median birth weight was 620 g (IQR, 530‐700 g). With a median of 23 months of follow up (IQR, 11‐39 months), mortality as of July 2018 was 27% (8 of 30). The alveolar‐arterial oxygen gradient as a measure of lung disease did not correlate with mortality (log‐rank test
P = 0.28). However, indexed pulmonary vascular resistance (PVR) of greater than 3 Woods units × m
2 showed a trend toward increased mortality (log‐rank test
P =
 0.12). Pulmonary vein stenosis was the only predictor significantly associated with mortality (log‐rank test
P =
 0.005).

Conclusions

In this cohort, the severity of lung disease as assessed by impaired oxygenation at cardiac catheterization did not correlate with mortality. The only factor significantly associated with mortality was the presence of pulmonary vein stenosis on cardiac catheterization, although PVR may also be an important factor.