bluuebunny/crossref_metadata_2025 huggingface dataset:
Abstract 885: The Role of Paraoxonase 2 (PON2) in Mitochondrial Membrane Phospholipid Composition and Lipid Peroxidation
Authors: Sulaiman Dawoud , Papesh Jeremy C , Meriwether David , Reddy Srinivasa T
Published: October 2019

Introduction:
We have recently reported that PON2 plays a protective role against myocardial ischemia-reperfusion injury (IRI) by reducing oxidative stress and mitochondrial dysfunction, in the form of improved calcium retention capacity and integrity of the mitochondrial membrane potential. It is known that mitochondrial phospholipids (PL) play critical roles in mitochondrial homeostasis via maintenance of normal bioenergetics and membrane function. These PLs undergo oxidative stress during IRI resulting in an increase in lipid peroxidation, damage of the respiratory complexes and loss of mitochondrial membrane potential.

Hypothesis:
PON2 protects cardiomyocytes against myocardial IRI by modulating the mitochondrial membrane phospholipid composition and lipid peroxidation.

Methods:
Two methods were developed to measure 1) various oxidized lipid species (i.e. 5, 12, and 15 HETE, 9, 13 HODE, and 5-oxoETE) and inflammatory markers (lipid panel) and 2) a panel of phospholipid species (i.e. PC, PE, PS) (PLP) via mass spectrometry (ESI LC-MS/MS). Mitochondria were isolated from male C57BL6/J (WT) and PON2 deficient (PON2-def) mice. PLs were then extracted using a modified Bligh and Dyer method with the respective internal standards, and run on a SCIEX 5500 QTrap run in negative ion mode and controlled by Analyst 1.6.2 software. Data is expressed as mean±SEM. Student’s T-test is used for statistical analysis, with p<0.05 considered statistically significant.

Results:
We determined that under baseline conditions, PON2-deficient mice have altered mitochondrial membrane PL composition and lipid peroxidation. We observe that PON2-def mitochondria have a significant decrease in various phosphatidylcholine species and an increase in phosphatidylethanolamine (42:9). In addition, there were variations in the composition of phosphatidylserine and phosphatidylinositol. The alteration of mitochondrial PL were accompanied by significant increases in various oxidized lipids including 9, 13-HODE, 14S, 17S-HDHA, 5, 15-HETE, and 5-oxoETE.

Conclusion:
Our preliminary studies point to the important role that PON2 plays in modulating mitochondrial PL composition and lipid peroxidation, and warrant further investigation under myocardial IRI.
Abstract 891: Phosphorylation of RNA Binding Motif 20 is a Novel Target to Reduce Myocardial Stiffness in Diastolic Dysfunction
Authors: Sun Mingming , Jin Yutong , Zhu Chaoqun , Rexiati Maimaiti , Cai Hanfang , Liss Martin , Gotthardt Michael , Ge Ying , Guo Wei
Published: October 2019

Introduction:
Published work has shown that RNA binding motif 20 (RBM20) can improve ventricular stiffening through altering titin sizes in HFpEF, a syndrome with no effective therapeutic options. Reducing RBM20 activity to treat diastolic dysfunction is promising, but it may cause side effects due to its multiple targets except for titin. RBM20 is one of the serine-arginine (SR) proteins of which the phosphorylation plays a critical role in gene splicing. Here we investigate the phosphorylation status of RBM20 and its potential role in diastolic dysfunction.

Methods:
Insect cell expression system was utilizedfor RBM20 expression. Purified RBM20 was subjected to the middle-down mass spectrometry (MS) analysis. Identified phosphorylation sites were mutated for
in-vitro
splicing and dual luciferase splice reporter assay through co-transfection with titin mini-gene.
In-vitro
kinase and co-IP assays were performed to identify the kinases that phosphorylate RBM20. Since phosphorylation is also important for translocation of RNA binding proteins, the confocal microscope was applied to estimate RBM20 trafficking.

Results:
Sixteen phosphorylation sites with four of them on SR domain of RBM20 were identified with MS analysis.
In-vitro
splicing and dual luciferase reporter assays revealed that two phosphorylation sites on SR domain play a major role in titin mini-gene splicing.
In-vitro
kinase assay indicated that kinases SRPK, CLK, and AKT can all phosphorylate RBM20, and co-IP confirmed the interaction between kinases and RBM20. Co-transfection of these kinases with RBM20 and titin mini-gene revealed that splicing pattern was different from co-transfection of mutated RBM20. Interestingly, two-phosphorylation sites mutation on SR domain facilitated RBM20 trafficking from the nucleus to the cytoplasm and thus, form RNA granules, suggesting the new role of RBM20 phosphorylation in diastolic dysfunction.
In-vivo
studies with mutation knock-in mouse model will be warranted in near future.

Conclusion:
These results suggest that RBM20 phosphorylation plays an important role in titin splicing, which is a potential target to treat diastolic dysfunction. RBM20 trafficking could be another new pathway to treat HFpEF.
Abstract 904: Disrupted Mechanobiology Links the Molecular and Cellular Phenotypes in Familial Dilated Cardiomyopathy
Authors: Greenberg Michael J , Clippinger Sarah R , Cloonan Paige E , Ernst Melanie , Stump Tom , Greenberg Lina
Published: October 2019

Familial dilated cardiomyopathy (DCM) is a leading cause of sudden cardiac death and a major indicator for heart transplant. The disease is frequently caused by mutations of sarcomeric proteins; however, one of the outstanding challenges in the field has been connecting mutation-induced changes in molecular function with the phenotype seen in cardiomyocytes. Many of the DCM mutation-induced changes in contractility at the molecular scale are subtle, begging the question of what other factors could link molecular-scale changes in contractile proteins with the cellular phenotype. We hypothesized that disease-causing mutations of sarcomeric proteins would likely affect not only contraction, but also how cardiomyocytes sense and respond to changes in their mechanical environment associated with aging and disease. To test this hypothesis, we studied the molecular and cellular consequences of a DCM mutation in troponin-T, deltaK210. We determined the molecular mechanism of deltaK210 using biochemical and biophysical tools, and then we used computational modeling to predict that the mutation should reduce the force per sarcomere in cells. In mutant human stem cell derived cardiomyocytes, we found that deltaK210 not only reduces contractility, but also causes cellular hypertrophy and impairs cardiomyocytes’ ability to adapt to changes in substrate stiffness (e.g., heart tissue fibrosis that occurs with aging and disease). These results link the molecular and cellular phenotypes and implicate impaired mechanosensing as an under-appreciated mechanism in the pathogenesis and progression of dilated cardiomyopathies. These results also have important implications for our understanding of multiple heart diseases and the design of precision therapeutics.
Abstract 905: Length Dependent Activation in Porcine Cardiac Myofilaments is Modulated by Mavacamten
Authors: Henze Marcus , Ma Weikang , Wong Fiona , Gong Henry , Anderson Robert , del Rio Carlos , Irving Thomas C
Published: October 2019

Length dependent activation (LDA) is a property of muscle where increased sarcomere length (SL) leads to increased force of contraction. Despite its key role in both normal and pathological states, the molecular mechanisms underlying LDA are not understood. Previous studies suggest that increased titin-based passive tension at longer SL triggers structural changes in the troponin complex leading to increased Ca
2+
sensitivity. Stretch also appears to release myosin heads from the OFF or super-relaxed state (SRX) increasing the number of available heads for cross-bridge formation, and, hence, maximum force. The small molecule inhibitor of myosin, mavacamten (mava) has been shown to stabilize the SRX state. Here, we used both stretch and mava on permeabilized porcine myocardium for force/pCa measurements coupled with x-ray diffraction to interrogate the mechanisms underlying LDA. Increasing SL from 2.0 to 2.3 um increases Ca
2+
sensitivity and elevates both diastolic and maximal tension (i.e. LDA). Mava abolished LDA while blunting the passive stiffness/tension relationship, suggesting increased compliance. The equatorial x-ray reflection intensity ratio, I
1,1
/I
1,0
, increases with stretch, indicating increased myosin head displacement towards actin. Stretch also decreases the intensities of both the m3 meridional and the MyBPC reflections, suggesting stretch-induced disordering of the thick-filament. Surprisingly, these findings in pig skinned muscle are opposite to those previously reported in intact rat muscle despite robust LDA in both preparations. Consistent with previous studies, stretch increases thick filament strain (indicated by changes in the m6 meridional spacing) and changes in the structure of the troponin complex (indicated by increased intensity of the third order troponin reflection), suggesting that the mechanism for increased Ca
2+
sensitivity are similar in both muscle systems. Interestingly, all diffraction pattern changes that occurred with stretch moved in the opposite direction in the presence of mava. Together, these data indicate that mava is not only capable of stabilizing the SRX state of myosin, but can modulate inter-filament interactions responsible for increasing Ca
2+
sensitivity and force.
Abstract 907: Understanding Cardiomyocyte Mechanosensing Utilizing CRISPR-Cas9 Based Screening Methods
Authors: Ladha Feria , Pettinato Anthony , Thakar Ketan , Hinson J. T
Published: October 2019

Heart failure (HF) is a leading cause of premature death that affects approximately 6.5 million patients in the United States and costs over $30 billion annually. HF is a complex disease that involves genetic and environmental factors, and is characterized by gradual deterioration of cardiac pump function. A key process implicated in the development of HF is mechanotransduction—the ability of cardiomyocytes to sense and respond to mechanical forces. While mechanotransduction signaling may play an adaptive role in response to changes in mechanical load, this process can become maladaptive, and ultimately lead to pathological hypertrophy and eventual HF. Gaining insight into cardiac mechanotransduction would solidify our understanding of how cardiomyocytes sense mechanical perturbations and will provide novel targets for the prevention and management of cardiomyopathy and HF.

To study perturbations in cardiomyocyte mechanosensing, we have developed a B-type natriuretic peptide (BNP) reporter assay in human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), which uses bright red fluorescent protein (tdTomato) to parallel endogenous BNP expression. Our reporter has been validated as a robust, scalable, and quantitative molecular marker of sarcomere function (inside-out) and substrate stiffness (outside-in). We have also generated a custom CRISPR guide RNA (gRNA) library targeting 75 extrinsic and intrinsic components of the cardiomyocyte mechanotransduction apparatus, enabling efficient analysis of single gene knockouts in our BNP reporter and providing a novel high-throughput model for interrogating the mechanical regulation of BNP expression. These gene candidates will be further tested in an
in vitro
HF model to assess functional response and the potential for phenotypic correction.
Abstract 915: Dysregulation of the Myosin and Myosin Binding Protein-C interaction in Hypertrophic Cardiomyopathy
Authors: Singh Rohit R , McNamara James W , Sadayappan Sakthivel
Published: October 2019

Rationale:
Affecting 1 in 300 individuals, hypertrophic cardiomyopathy (HCM) is a genetic heart disease characterized by left ventricular hypertrophy, myocardial disarray, and sudden cardiac death. Often, HCM is associated with myocardial hypercontractility. The subfragment-2 (S2) of beta-myosin heavy chain contains a cluster of missense and deletion mutations associated with severe HCM. Interestingly, myosin S2 interacts with the C0-C2 region of cardiac myosin binding protein C (cMyBP-C) in a phosphorylation-dependent manner to regulate sarcomere contractility. However, the nature of myosin S2 and cMyBP-C interactions and the mechanism(s) by which mutations in myosin S2 cause HCM remain to be elucidated.

Objective:
To determine whether mutations in myosin S2 weaken its interaction with cMyBP-C, resulting in enhanced myofilament contractility.

Methods and Results:
Myosin S2 proteins (126 amino acids) containing three clinically relevant mutations (R870H, E924K, E930del, or wild type), and recombinant C0-C2 region of cMyBP-C were produced and purified by metal affinity chromatography. Solid-phase binding assays and isothermal calorimetry experiments revealed a significantly dampened binding to C0-C2 for these three mutants in myosin S2 (30% lower than wild type, p<0.002), suggesting that mutations in S2 regions reduce their bindings to cMyBP-C. Conversely, upon protein kinase A phosphorylation of C0C2, these S2 mutants displayed an increased affinity to cMyBP-C, an effect opposite that of wild-type S2. Structural analyses of these mutations within myosin S2 are predicted to reduce the alpha-helical content, thereby reducing stability of the critical coiled-coil structure.

Conclusions:
Mutations in myosin S2 result in reduced binding to cMyBP-C. Functionally, this would result in a greater attachment of cross-bridges, and thus enhance myofilament contractility. Strikingly, these mutations increase their affinity to cMyBP-C upon phosphorylation, demonstrating fundamental changes to the regulation of contractile function.
Abstract 937: Etv2 Regulates Endothelial Gene Expression With Its Novel Binding Partner Vezf1
Authors: Das Satyabrata , Singh Bhairab N , Gong Wuming , Skie Erik , Garry Daniel J , Garry Mary G , Gupta Vinayak , Theisen Joshua
Published: October 2019

Ets transcription factors function as important developmental regulators and are known to be modulators of cell fate. Previously, in conjunction with co-factors, we have described Ets variant 2 (Etv2) as an essential regulator of the hematopoietic and endothelial lineages. But the mechanism and the Etv2 interacting partners involved in achieving this critical function remains poorly understood. Through Yeast two-hybrid analysis we identified Vascular Endothelial Zinc Finger 1 (Vezf1) as an interacting factor with Etv2. Vezf1 is a conserved C2H2 zinc finger transcription factor known to regulate the formation, proliferation, and migration of endothelial cells through several gene targets. We verified Vezf1 as a binding partner of Etv2 through co-immunoprecipitation and GST-pull down studies. Bioinformatic analysis of ChIP-seq and Etv2-expressing single cell RNA sequencing was conducted to identify candidate genes containing both Etv2 and Vezf1 binding motifs in their regulatory regions. Histone deacetylase 7 (Hdac7) and angiomotin like protein 2 (Amotl2) were identified as genes of interest involved in endothelial development. Hdac7 is a conserved class II deacetylase that functions in endothelial cell adhesion and vascular integrity. Amotl2 is a Motin family protein that functions in angiogenesis, endothelial cell polarity and migration. RT-qPCR analysis showed upregulation of Hdac7 and Amotl2 in response to doxycycline inducible Etv2 and Vezf1; whereas significant reduction of expression of these two genes was observed in the Etv2 and Vezf1 knockout cells. Chromatin immunoprecipitation (ChIP) and electrophoresis mobility shift assays (EMSA) confirmed Etv2-Vezf1 adjacent binding sites in the promoters of Hdac7 and Amotl2. Histone Acetyl transferase (HAT) assays was performed to investigate Etv2-Vezf1 on global histone acetylation conditions in doxycycline inducible embryoid bodies. Vezf1 overexpression results in a significant reduction of acetylated histone. In summary, this study identifies Vezf1 as a novel binding partner of Etv2 and their combined role in regulating downstream target genes Amotl2 and Hdac7 in hematoendothelial development.
Declining Gender Differences in Low-Wage Employment in Germany, Austria and Switzerland
Authors: Fritsch Nina-Sophie , Verwiebe Roland , Liedl Bernd
Published: October 2019

Although the low-wage employment sector has enlarged over the past 20 years in the context of pronounced flexibility in restructured labor markets, gender differences in low-wage employment have declined in Germany, Austria and Switzerland. In this article, the authors examine reasons for declining gender inequalities, and most notably concentrate on explanations for the closing gender gap in low-wage employment risks. In addition, they identify differences and similarities among the German-speaking countries. Based on regression techniques and decomposition analyses (1996-2016), the authors find significantly decreasing labor market risks for the female workforce. Detailed analysis reveals that (1) the concrete positioning in the labor market shows greater importance in explaining declining gender differences compared to personal characteristics. (2) The changed composition of the labor markets has prevented the low-wage sector from increasing even more in general and works in favor of the female workforce and their low-wage employment risks in particular.
Generalization in Comparative History
Authors: Clark Samuel
Published: October 2019

This article examines a sample of comparative-historical literature to assess when convincing generalizations are made and when they are not. Although a variety of factors can affect the potential for generalization, the focus here is on the difference between diachronic and synchronic generalizations. Separate sections are devoted to synchronic-idiographic, synchronic-nomothetic, diachronic-idiographic, and diachronic-nomothetic analysis and research. Evidence is presented to demonstrate that synchronic generalizations are common in comparative history. The most attention in the article is, however, given to the challenges faced when generalizing diachronically and especially when generalizing sequentially. The article ends with a discussion of the effects of inter-societal forces on comparative-historical generalization and with a conclusion outlining when comparative-historical generalizations seem to be more or less successful.
Clarifying the Eclipse
Authors: Ungvary David
Published: October 2019

This essay examines a literary exchange between the Visigothic poet-king Sisebut (612-621 AD) and his scholar-bishop Isidore of Seville following an anomalous sequence of eclipses. After Sisebut commissioned a scientific treatise from Isidore on such natural phenomena, he responded to the bishop’s prose with a short poem on lunar eclipses (De eclipsi lunae). This study interprets the exchange of texts not as a literary game, but as high-stakes political correspondence. It situates the king’s verses in an ongoing process of cultural construction in Visigothic Spain, led prominently by Isidore himself, but also tied to a rising ascetic movement. It argues that Sisebut was attuned to Isidore’s designs to manage the discourses through which Christian power was proclaimed, and shows how the king attempted to versify in accord with scientific truth so as to fit within Isidore’s ascetic intellectual program.
A distinctive new species of flowerpecker (Passeriformes: Dicaeidae) from Borneo
Authors: SAUCIER JACOB R. , MILENSKY CHRISTOPHER M. , CARABALLO-ORTIZ MARCOS A. , RAGAI ROSLINA , DAHLAN N. FARIDAH , EDWARDS DAVID P.
Published: October 2019

The enigmatic ‘Spectacled Flowerpecker’—a probable new bird species from the island of Borneo—was first sighted in the Danum Valley of Sabah, Malaysia in 2009. However, the absence of a holotype specimen has prevented its formal scientific description. Since then only a handful of reports from widely disparate localities across the island have emerged, all from lowland sites and often in close association with fruiting mistletoe. Here, we report the long-awaited capture of a specimen of this putative new species and confirm its morphological and molecular distinctiveness as a novel species in the genus Dicaeum.
A new genus and species of Stigmoderini Lacordaire, 1857 (Coleoptera: Buprestidae: Buprestinae) from Southeast Brazil with notes on its hypothesized mimicry complex
Authors: PINEDA CRISTIAN R. , KOIKE RICARDO M. , BARROS RAFAEL C.
Published: October 2019

Lampygnatha ikuoi gen. & sp. nov. is described and illustrated from southeast Brazil. A hypothesized mimicry complex that involves the new taxon, Allocerus spencei Kirby (Coleoptera: Cerambycidae) and Cratomorphus splendidus (Drury, 1782) (Coleoptera: Lampyridae) is discussed. A key to the identification of all genera of New World Stigmoderini is presented.
Effect of Sandblasting Treatment on the Bond Strength of the Veneering Porcelain and Zirconia All-Ceramic Crown: A Meta-Analysis
Authors: Yang Qian , Wu Wei-Wei , Sun Ming-Yue , Zhao Li-Ang , Babar-Shahzad M. , Yang Hua-Zhe
Published: October 2019

Sandblasting is a relatively common surface treatment for zirconia all-ceramic crown. However, the effect of sandblasting on the bond strength of veneering porcelain and crown is controversial in literatures. A meta-analysis can provide systematic analysis on the results of different
studies. In this paper, meta-analysis was used to study the effect of sandblasting on the bond strength between the veneering porcelain and zirconia crown. First, the Medline database was adopted for literature retrieval, and then the quality of the literature was assessed, as well as screening
and exclusion of the literature manually. Finally, 24 papers were included in the study after the data extraction and Review Manager software was adopted for data analysis. After the analysis, it was showed that the results of study in literatures were not biased, but there was significant
heterogeneity. Then further removing the literature with large differences in data, the data were analyzed again, and the result still had high heterogeneity. Therefore, according to the current results, the sandblasting treatment could not increase the bond strength between the veneering
porcelain and zirconia crown.
A Novel Strategy to Tune Magnetic Properties of Nickel(II)-Schiff Base Coordination Bridged Polysilsesquioxane
Authors: Feng Yijun , Zhang Jincheng , Pei Yongbing , Chen Qiu , Yan Yue , Wu Lianbin
Published: October 2019

In this paper, liquid state solvent-free organosilica-based nickel-bithiazole complexes (PBSIBTHM-Ni2+, PBSIBTMeM-Ni2+) were synthesized through sol–gel processes respectively, and these two metal complexes and their precursors were characterized. The precursors
with bithiazole were successfully prepared, their inorganic and organic parts were connected on molecular level. The DSC results indicated they would all exist in liquid phase at temperature ranging from 180 K to 280 K. The UV-VIS showed that a red shift of the main electronic transitions
from 254 to 268 nm of PBSIBTHM to PBSIBTHM-Ni2+, Δν = 14 (from 249 to 266 nm of PBSIBTMeM to PBSIBTMeM-Ni2+, Δν = 17). This verified the formation of a more extensive π→π* conjugating system due to coordination
interaction between Ni2+ and PBSIBTHM or PBSIBTMeM. The magnetic measurement results of PBSIBTHM-Ni2+ and PBSIBTMeM-Ni2+ reflected they both exhibited ferromagnetic properties at low temperature. For PBSIBTMeM-Ni2+, it had a transition temperature
(Ttran) at 160 K, and became an anti-ferromagnet above Ttran. For PBSIBTHM-Ni2+, it had a very high Curie-Weiss temperature (Tc = 253 K). This strategy was expected to find potential application in fabricating the complexes with
desired physicochemical properties.
Mesoporous Magnetic Carbon Adsorbents Prepared from Sugarcane Bagasse and Fe2+ and Fe3+ via Simultaneous Magnetization and Activation for Tetracycline Adsorption
Authors: Mahawong Sirinad , Dechtrirat Decha , Watcharin Waralee , Wattanasin Panwadee , Muensit Nantakan , Chuenchom Laemthong
Published: October 2019

Tetracycline (TC) is one of the pharmaceutical antibiotics most employed for human and veterinary use in Thailand. The release of TC is considered a threat to the aquatic environment; hence, it urgently needs to be efficiently removed from the water streams. One of the popular and effective
methods of removal of TC is adsorption. Magnetic carbon composites derived from biomass-based materials have attracted attention as novel adsorbents for removal of toxic substances from aqueous solution. However, their preparation involves multi-step procedures, which is time and energy consuming.
In this work, we have prepared novel magnetic carbon composites using sugarcane bagasse, abundantly wasted biomass from sugar industries, a mixture of Fe2+ and Fe3+, and NaOH, as a carbon precursor, source of magnetite particles (Fe3O4), and precipitating/activating
agent, respectively. The facile preparation has been performed via a simultaneous magnetization and activation process in a single step. The effects of preparation conditions on physicochemical properties of the resulting materials were studied, discussed and optimized. A selected sample showed
satisfactory magnetic stability due to the presence of Fe3O4 particles (confirmed by XRD) and high porosity, with a BET surface of 566 m2/g and mesopore fraction (pore size > 2 nm) of more than 84%, suitable to adsorb the large TC molecules. The adsorption
performance towards TC was determined using batch adsorption experiments. The maximum TC adsorption on the selected sample was as high as 48.40 mg/g, outperforming many literature sorbents, while the magnetic stability can even be retained after complete adsorption.
Investigation on Strontium Adsorption Selectivity of Hydrothermally Synthesized Layered Sodium Titanates
Authors: Kunishi Hiroto , Hagio Takeshi , Kamimoto Yuki , Ichino Ryoichi
Published: October 2019

Two layered sodium titanate phases, sodium nonatitanate (Na4Ti9O20) and sodium trititanate (Na2Ti3O7), have been hydrothermally synthesized and their Sr2+ adsorption selectivity was investigated in the coexistence
of Cs+ with ionic equivalent concentration. Although both phases exhibit Sr2+ selective adsorption, Na4Ti9O20 adsorbed both Sr2+ and Cs+, while the adsorption of Cs+ was not detected on Na2Ti3O7,
despite its higher adsorption capacity. To investigate the causes for the high Sr2+ selectivity of Na2Ti3O7, additional adsorption tests were carried out in different pH, which can be interpreted as the Sr2+ –H+ binary
system, and in single and ternary systems of Al3+, Sr2+ and K+ with ionic equivalent concentrations. When changing the pH, the adsorption amount of Sr2+ showed a high and nearly constant value at pH above 4 and drastically decreased at pH below 3,
reaching nearly zero at pH 2. In the Al3+–Sr2+ –K+ ternary system, the adsorption amount decreased in the order of Sr2+, Al3+ and K+. The adsorption amount of K+ was low compared to that of Sr2+
and Al3+ in both the single and ternary systems. Meanwhile, the adsorption amount of Sr2+ significantly decreased compared to that in the single system, unlike in the Sr2+–Cs+ binary system where the adsorption of Sr2+ was almost
the same. From these results, the high Sr2+ selectivity of Na2Ti3O7 in the Sr2+–Cs+ binary system was anticipated to be due to the size effect. The smaller interlayer spacing of Na2Ti3O7
compared to that of Na4Ti9O20 appears to inhibit the intercalation of Cs+ due to its large ionic radius.
Electrochemical Investigations of Microbiologically Influenced Corrosion on 316L-Cu Stainless Steel by Pseudoalteromonas lipolytica
Authors: Kalnaowakul Phuri , Yingsamphancharoen Trinet , Yang Ke , Xu Dake , Rodchanarowan Aphichart
Published: October 2019

Microbiologically influenced corrosion (MIC) is becoming more often a risk factor in several industries, such as offshore, cooling water systems and construction. The Pseudoalteromonas lipolytica (P. lipolytica) is a highly corrosive aerobic marine bacterium. In this work,
the 316L-Cu SS was investigated the corrosion behavior under the abiotic medium and biotic medium of P. lipolytica. Based on the electrochemical analysis, the corrosion current density (icorr) under the biotic medium is higher than that under the abiotic medium. The
presence of P. lipolytica has led to the dissolution of the passive film of 316L-Cu SS, which initiates the localized pitting corrosion. However, the addition of Cu in 316L SS by melting in the vacuum induction furnace improved more corrosion-resistant than without the addition of Cu.
Effects of Tetraethyl Orthosilicate on Improving Adhesion Between Polyurethane Sponge/Hydrophobic Silica Gel Composite Materials for Oily Wastewater Treatment
Authors: Prompawilai Arisa , Yodyingyong Supan , Triampo Darapond
Published: October 2019

The environmental disposal of oily wastewater is a challenge to household and food industries. Cost-effective oil absorbent materials for oily wastewater treatment have been developed by various methods, one of which, the modification with hydrophobic particles. However, the oil absorbents
still suffer high cost and low reusability because of the insufficient adhesion between supported material and the hydrophobic particles. Herein, a low cost and simple method to fabricate oil absorbents were reported by immersing commercial polyurethane (PU) sponge in hydrophobic silica gel.
The adhesion between hydrophobic silica gel to the 3D surface of PU was assisted with the use of tetraethyl orthosilicate (TEOS) as a silane coupling agent. Only 0.5% TEOS was required for up to 73% improvement of adhered calculated from % silica loading. The use of TEOS showed adhesion enhancement
between the surface of PU and the silica which in turn improve reusability. Reusability test mimics the real situation of squeezing the PU/silica sponge to demonstrate good mechanical properties and flexibility. Furthermore, the PU/silica sponge displayed good and rapid absorption capacity.
Results from Water Contact Angle (WCA), Scanning Electron Microscopy (SEM) and Fourier-transform infrared spectroscopy (FT-IR) were also used to confirm successful modification of PU with hydrophobic silica gel.
Preparation of Silica Aerogels Monoliths from Hydrophobic Silica Gels and Pluronic10R5 via Sol–Gel Process
Authors: Eangpayung Supattra , Yodyingyong Supan , Triampo Darapond
Published: October 2019

Silica aerogel, the most common type of aerogels, comprised of 95% air in its structure which made the aerogel has a high surface area, high porosity, low density, and low thermal conductivity. Because of its structure and high porosity, one of its major weakness compared to other materials
is being very brittle. This study aims at strengthening the connection points between silica nanoparticles using Pluronic10R5 (poly(propylene oxide)8–poly(ethylene oxide)22–poly(propylene oxide)8) where the Pluronic10R5 was used to reduce phase
separation during the silica condensation reaction in the sol–gel process. Silica aerogel monoliths were prepared via a sol–gel process from hydrophobic silica gels and Pluronic10R5 with an ambient pressure drying (APD) process. Results from the compression test showed that the
Pluronic10R5/silica aerogels have improved mechanical property by ten times that of unmodified silica aerogels. A thermogravimetric analysis (TGA) showed a mass loss at 300–400 °C that is attributed to the surface methyl group, while a mass loss at 200 °C refers to the loss of
Pluronic10R5 which confirms the incorporation of Pluronic10R5 into the monolith. Moreover, infrared (IR) images revealed that the top surface temperature of Pluronic10R5/silica aerogels monolith is about 80 °C differs from the bottom heat source temperature of 160 °C.
Development of Grease Resistant Packaging Paper Using Cellulose Nanocrystals and Sodium Alginate
Authors: Setajit Chanyanutch , Kongvarhodom Chutima , Xiao Huining
Published: October 2019

A biodegradable packaging paper with excellent grease resistance was produced using cellulose nanocrystals and sodium alginate. This study aims to reduce the porosity of paper by filling the pores with cellulose nanocrystals and using sodium alginate as a binder. Different types of
papers, including filter paper, copy paper, and supercalendered paper, were used. Pure cellulose nanocrystals and cellulose nanocrystals/sodium alginate solutions at different concentrations and ratios (2:8, 5:5, and 9:1 by weight ratio) were applied to papers by coating and impregnation techniques.
The resulting papers were then characterized with atomic force microscopy and scanning electron microscopy for the surface morphology. The grease barrier and the mechanical property were investigated in accordance with TAPPI standards. The results demonstrated that the copy paper coated with
2:8 of cellulose nanocrystals/sodium alginate showed excellent grease barrier properties. Within 48 h of the test period for grease to penetrate the coated paper, almost 100% of the grease barrier was achieved when the coating weight was set at 4 g/m2. The roughness of the paper
surface significantly decreased, thereby resisting the penetration of oil from one side to another. Moreover, the mechanical property of both cellulose nanocrystals- and cellulose nanocrystals/sodium alginate-coated papers was improved due to the addition of cellulose nanocrystals as a reinforced
filler.
Nanostructured Cerium-Oxide-Based Screen Printed Electrode for Electrochemical Detection of Melamine via Ascorbic Acid
Authors: Mishra Sapna , Chishti Benazir , Fouad H. , Seo H. K. , Ansari Z. A.
Published: October 2019

Nanostructured cerium oxide (CNP) was synthesized via co-precipitation and used as a base matrix to construct an enzyme-less electrochemical sensing platform for a non-electroactive analyte (i.e., melamine in the presence of ascorbic acid (AA)). CeO2 was screen printed (SP)
on prefabricated gold electrodes for the indirect detection of melamine. The melamine concentrations varied in the range of 0.01 ppb to 10 ppm with a fixed amount of ascorbic acid (i.e., 50 ppm). Absorption spectra were obtained from 220 to 400 nm for all melamine concentrations. The cyclic
voltammogram (CV) for different melamine concentrations was obtained in the applied voltage range of –1 to +1 V. The peak oxidation current reduced as a function of increased melamine concentration in the presence of ascorbic acid, which was supported by absorption studies. The obtained
melamine sensitivities were 64.9 and 80.8 μA/ppb/mm2, respectively, without and with ascorbic acid. The limits of detection estimated from three times the signal-to-noise ratio were 1.5 × 10–3 and 2.4 × 10–3 ppb, which are
the lowest values so far reported to the best of our knowledge. The electrochemical impedance study predicted the increase of the charge transfer characteristics in the presence of AA, which comprehensively correlated with the CV data. The developed sensor can be used for the detection of
melamine in milk, dairy products, and other food items.
Midwinter Suppression of Storm Tracks in an Idealized Zonally Symmetric Setting
Authors: Novak Lenka , Schneider Tapio , Ait-Chaalal Farid
Published: October 2019

The midwinter suppression of eddy activity in the North Pacific storm track is a phenomenon that has resisted reproduction in idealized models that are initialized independently of the observed atmosphere. Attempts at explaining it have often focused on local mechanisms that depend on zonal asymmetries, such as effects of topography on the mean flow and eddies. Here an idealized aquaplanet GCM is used to demonstrate that a midwinter suppression can also occur in the activity of a statistically zonally symmetric storm track. For a midwinter suppression to occur, it is necessary that parameters, such as the thermal inertia of the upper ocean and the strength of tropical ocean energy transport, are chosen suitably to produce a pronounced seasonal cycle of the subtropical jet characteristics. If the subtropical jet is sufficiently strong and located close to the midlatitude storm track during midwinter, it dominates the upper-level flow and guides eddies equatorward, away from the low-level area of eddy generation. This inhibits the baroclinic interaction between upper and lower levels within the storm track and weakens eddy activity. However, as the subtropical jet continues to move poleward during late winter in the idealized GCM (and unlike what is observed), eddy activity picks up again, showing that the properties of the subtropical jet that give rise to the midwinter suppression are subtle. The idealized GCM simulations provide a framework within which possible mechanisms giving rise to a midwinter suppression of storm tracks can be investigated systematically.
Seasonal Characteristics of Mesoscale Coupling between the Sea Surface Temperature and Wind Speed in the South China Sea
Authors: Sun Shuangwen , Fang Yue , Zu Yongcan , Liu Baochao , Tana  , Samah Azizan Abu
Published: October 2019

The seasonal characteristics of the mesoscale coupling between sea surface temperature (SST) and wind speed in the South China Sea (SCS) are investigated using satellite observations. The correlation between mesoscale SST and wind speed is highest in winter. The region of high correlation is located in the central SCS in the early stage of the winter monsoon. It then gradually shifts northward in the following months and is located in the northern SCS in the late stage of the winter monsoon. In summer, the region of high correlation is located to the east of the Vietnam coast. Two controlling factors are crucial in mesoscale SST–wind speed coupling: the mesoscale SST gradient and the wind speed steadiness. The mesoscale SST gradient is fundamental in mesoscale coupling, but a steady wind speed also plays an important role. The development of significant coupling depends on the relative contribution of these two factors. For regions where the mesoscale SST gradient is relatively weak, a very steady wind field is required for detectable mesoscale coupling to occur, whereas in regions where the wind speed is less steady, a stronger mesoscale SST gradient must exist for coupling to develop. Variations in wind speed steadiness can well explain the inconsistency between the spatial patterns of the mesoscale SST gradient and the intensity of coupling. The wind speed steadiness is a good factor with which to evaluate the constraining effect of the background wind field variability on the development of mesoscale coupling in the SCS.
Reexamination of the Tropical Cyclone Wind–Pressure Relationship Based on Pre-1987 Aircraft Data in the Western North Pacific
Authors: Bai Lina , Yu Hui , Black Peter G. , Xu Yinglong , Ying Ming , Tang Jie , Guo Rong
Published: October 2019

The wind–pressure relationship (WPR) for tropical cyclones (TCs) in the western North Pacific is reexamined based on aircraft data, TC best track data, and daily reanalysis data during 1957–87. Minimum sea level pressure (MSLP) was estimated from aircraft reconnaissance, and maximum surface wind speeds (MSWs) were adjusted from the maximum wind speed at flight level. The mean MSLP was found to be higher during 1957–64 than during 1965–87, presumably due to the change in reconnaissance instrumentation and technology, which results in a systematic MSW bias (too high) before 1965 in the China Meteorological Administration (CMA) dataset. Further analyses found that the WPR used in the CMA dataset is more accurate for strong TCs, while the WPR in the Tokyo Regional Specialized Meteorological Center (RSMC) dataset is better for weak TCs after the MSW-RSMC converted by the Dvorak conversion table (1984) and when using the aircraft datasets as a baseline. Several prevailing operational WPRs used in the western North Pacific are reexamined. Results show that the WPR of Knaff and Zehr explains 71% of the variance with a MAE of 9.22 hPa, which represents a significant improvement over other WPRs. Utilizing data after 1965 (a total of 1874 samples), the effects of TC center latitude, size, translation speed, intensification trend, and environmental pressure on the WPRs were examined. Results show that faster-traveling TCs, smaller in size, and located in a higher environmental pressure at lower latitudes, exhibited a higher MSLP for a given MSW. Meanwhile, the latitude, translational speed, and the environmental pressure produces additional improvement, but the TC size and intensity change added only a little skill to the WPR equation.
Combined Three-Stage 7-Day Weighted Analog Intensity Prediction Technique for Western North Pacific Tropical Cyclones: Demonstration of Optimum Performance
Authors: Tsai Hsiao-Chung , Elsberry Russell L.
Published: October 2019

The original 7-day weighted analog intensity Pacific (WAIP) prediction technique is improved by developing a new version for the preformation stage and combining it with the bifurcation version that is especially for the intensification stage and the ending-storm stage WAIP. This combined three-stage WAIP includes a calibrated intensity spread designed to include 68% of the verifying intensities. In this demonstration of the optimum performance of the combined WAIP, the Joint Typhoon Warning Center (JTWC) best tracks, the time to formation (T2F), and ending-storm time are utilized as inputs along with the initial intensity [i.e., either 15 or 20 kt (1 kt ≈ 0.51 m s−1)]. In the new “Before Formation” (defined as 25 kt) stage of the WAIP, the intensity evolution is represented by a square function between the initial intensity and the T2F (25 kt), and very small mean absolute errors (MAEs) and intensity spreads are achieved. In the bifurcation version, correct selections between two cluster WAIP intensity evolutions lead to MAEs that slowly increase to 17 kt at 144 h, and the intensity spreads are relatively small as well. Because the ending-storm time constrains the analog selection in the WAIP, the MAEs begin to decrease after 72 h and are only 10 kt at 156 h. A case study is presented as to how an ensemble storm-track forecast along with the T2F could provide WAIP 7-day intensity predictions beginning in the preformation stage, which indicates the potential for earlier guidance for the JTWC intensity forecasts of western North Pacific tropical cyclones.
High-Precision Continuous-Wave Terahertz Spectroscopy Based on a Photomixing Technique for Identifying Pearls
Authors: Kim Chihoon , Ji Taeksoo
Published: October 2019

We present the accurate terahertz spectra of between imitation and cultured pearls using continuous-wave terahertz (CW-THz) spectroscopy. Using Fourier transform infrared (FT-IR) spectroscopy and optical coherence tomography (OCT) measurements, cultured pearls can be distinguished from imitation pearls by observing distinct absorption peaks and discriminative boundaries. The THz absorption spectra up to 0.3 THz obtained from CW-THz spectroscopy show several absorption peaks at specific frequencies with the cultured pearls but no peaks with the imitation pearls, which results from the existence of the nacre polymorph of cultured pearls. Hence, it is expected that the CW-THz system proposed herein will be applicable to fast, nondestructive spectrum analysis including pearl identification.
Fluorescence Turn-On Detection of Ascorbic Acid Using a Self-Assembled Lanthanide Polymer Nanoparticle
Authors: Zeng Hui-Hui , Liu Fang , Hu Long-Ke , Deng Jie , Xie Yue-Ping , Xiao Wei , Lai Pei-Qing , Wang Yong , Feng Ya-Feng , Yu Jing-Chen
Published: October 2019

Ascorbic acid (AA), or vitamin C, is an important reactive biological molecule in vivo, and an abnormal level of AA is associated with many diseases. Therefore, the rapid, sensitive, and selective detection of AA levels is of significance in cases of medical assay and diagnosis. Compared with other nanoparticles, lanthanide coordination polymer nanoparticles (Ln-CPs) have been demonstrated as the excellent biomolecule sensing platforms due to their unique optical properties and intrinsic porosities. In this work, the cerium coordination polymer nanoparticles ATP-Ce-Tris were synthesized in a simple and quick way. The synthesized ATP-Ce-Tris nanoparticle shows the characteristic peak of Ce3+located at 365 nm, which is corresponding to the 4f→5d transition of Ce3+. In the presence of Fe3+, the fluorescence of ATP-Ce-Tris quenched, and the following added ascorbic acid (AA) makes it restoring effectively. Based on this, we constructed a fluorescence probe with excellent sensitivity for AA sensing in a wide linear relationship from 0.05 to 500 μM. The detection limit was as low as 18 nM (signal-to-noise ratio of three), which is one or two orders of magnitude lower than those of reported sensors. The proposed sensing systems also exhibits excellent sensitivity for AA detection in human serum sample, exploiting a valuable platform for AA analysis in clinic diagnostic and drug screening.
Surface-Enhanced Raman Spectroscopy (SERS) of Neonicotinoid Insecticide Thiacloprid Assisted by Silver and Gold Nanostructures
Authors: Atanasov Petar A. , Nedyalkov Nikolay N. , Fukata Naoki , Jevasuwan Wipakorn , Subramani Thiyagu
Published: October 2019

This study expresses our results on surface-enhanced Raman spectroscopy (SERS) analyses of neonicotinoid insecticide thiacloprid, i.e., Calypso 480 SC, in quantities much smaller than usually applied in the agricultural medicine. Advanced Ag and Au nanostructures created by the thermal deposition technique on Al2O3 ceramic were applied as active substrates for SERS analyses. The minimum concentration of thiacloprid detected was 380 µM and the enhancement factor was estimated to be about 3 × 103. The intensity of the SERS peaks increased by an order of magnitude after pulsed laser annealing of the films and formation of nanoparticle arrays and the enhancement factor reached ≈104, respectively. The proposed study has direct bearing on the environment and human health by detection of small amounts or residue of harmful pollutants using a relatively cheap and easy method to produce active SERS substrates.
Modeling of Carbon Monoxide Two-Photon Laser-Induced Fluorescence (LIF) Spectra at High Temperature and Pressure
Authors: Carrivain Olivier , Orain Mikael , Dorval Nelly , Morin Céline , Legros Guillaume
Published: October 2019

In this study, quantitative model of two-photon excitation and fluorescence spectra of carbon monoxide based on up-to-date spectroscopic constants collected during an extensive literature survey was developed. This semi-classical model takes into account Hönl–London factors, quenching effects (collisional broadening and shift), ionization and stark effect (broadening and shift), whereas predissociation is neglected. It was specifically developed to first reproduce with a high confidence level the behavior of our experimental spectra obtained from laser-induced fluorescence (LIF) measurements, and then to allow us to extrapolate the fluorescence signal amplitude in other conditions than those used in these experiments. Synthetic two-photon excitation and fluorescence spectra of CO were calculated to predict the fluorescence signal at high pressures and temperatures, which are representative of gas turbine operating conditions. Comparison between experimental and calculated spectra is presented. Influence of temperature on both excitation and fluorescence spectra shapes and amplitudes is well reproduced by the simulated ones. It is then possible to estimate flame temperature from the comparison between experimental and calculated shapes of numerical excitation spectra. Influence of pressure on both excitation and fluorescence spectra was also investigated. Results show that for temperature below 600 K and pressure above 0.1 MPa, the usual Voigt profile is not suitable to reproduce the shape of the excitation spectrum. We found that the Lindholm profile is well suited to reproduce the pressure-dependence of the spectrum in the range 0.1 to 0.5 MPa at 300 K, and 0.1 to 0.7 MPa at 860 K. Beyond 0.7 MPa, in this temperature range, it is shown that the Lindholm profile does no longer match the spectral profiles, in particularly the red wing. Further analyses taking into account the line mixing phenomenon at higher pressure are thus discussed.