bluuebunny/crossref_metadata_2025 huggingface dataset:
SERS Comparison from Au, Ag, and Au-Ag Alloys: Insights by the First Principles
Authors: Takenaka Masato , Hashimoto Yoshikazu , Iwasa Takeshi , Taketsugu Tetsuya , Seniutinas Gediminas , Balcytis Armandas , Juodkazis Saulius , Nishijima Yoshiaki
Published: April 2018

Surface enhanced Raman scattering (SERS) is presented via a case study of 2,2’-bipyridyl(22BPY) molecules adsorbed on pure Au and Ag as well as on Au-Ag alloy nanodiscs. ExperimentalSERS spectra from Au and Ag nanodics show similar peaks, but those from Au-Ag alloyreveal new spectral features. The physical enhancement factors due to surface nano-texture wereconsidered by numerical simulations of light intensity distribution for the nano-textured Au, Ag,and Au-Ag alloy surfaces, but found to cause only minor differences. For the chemical insights ofenhancement, the density functional theory (DFT) calculations were performed using Au20, Ag20,and Au10Ag10 clusters of a pyramidal structure for SERS modeling. Binding of 22BPY to the clusterswas simulated by considering possible arrangements of vertex and planar physical as well aschemical adsorption models. A qualitative match with experimental SERS results for the pure Auand Ag was obtained. DFT models showing spectral shifts of 22BPY SERS on the alloy nanodiscsare presented.
Hands-On Experiments in the Interactive Physics Laboratory: Students’ Intrinsic Motivation and Understanding
Authors: Snětinová Marie , Kácovský Petr , Machalická Jana
Published: April 2018

Experiments in different forms can certainly be suitable tools for increasing student interest in physics. However, educators continuously discuss which forms of experimenting (if any) are the most beneficial for these purposes. At the Faculty of Mathematics and Physics, Charles University, Prague, two different forms of physics experiments are offered to upper secondary students: hands-on experimental work in the InteractivePhysics Laboratory, and physics demonstration shows where the students watch experiments conducted by a lecturer. Our research focuses primarily on student feedback about their immediate attitudes towards these two projects. Data collection was undertaken using questionnaire research based on the Intrinsic Motivation Inventory. This research was subsequently supplemented with a qualitative study examining the influenceof students’ experimental work in the Interactive Physics Laboratory on their understanding of selected physics concepts. The results of the main research show that the two projects do not exhibit significant differencesin terms of student interest and perceived usefulness; nevertheless, students felt the need for significantly more effort and experienced pressure during their work in the Interactive Physics Laboratory. One interestingfinding, which goes against our original hypothesis, is that grades in physics are quite a strong predictor of students’ assessment of the projects: better grades indicate more positive assessment of both projects as well as less pressure felt during hands-on activities in the laboratory.
Efecto del fraccionamiento de la fertilización nitrogenada aplicada al trigo sobre la calidad de su semilla
Authors: González-Figueroa Sarahyt Santamaría , Aguirre-Mancilla Cesar Leobardo , Covarrubias-Prieto Jorge , Cervantes Ortiz Francisco , Grageda-Cabrera Oscar Arath
Published: April 2018

Las semillas son un elemento indispensable en la producción agrícola y representan uno de los medios para mejorar el rendimiento en los cultivos y la fertilización es indispensable para la producción de semillas de alta calidad. En el presente trabajo se evaluó la calidad de la semilla de trigo cuando el fertilizante-N se fracciona en diferentes porcentajes. Las variedades utilizadas fueron Gema C2004, Nana F2007 y Urbina S2007. La dosis de fertilización N-P-K recomendada en la región de El Bajío es de 240-60-00. Los fraccionamientos de la fertilización-N (FFN) fueron a la siembra, 45 días después de la siembra (dds) y 75 dds en los siguientes porcentajes: 1) 00-00- 00, 2) 100-00-00, 3) 00-100-00, 4) 50-50-00, 5) 00-50-50, 6) 70-30-00, 7) 30-70-00, 8) 00-30-70, 9) 00-70-30 y 10) 33-33-33. En campo se evaluó el rendimiento, en laboratorio la calidad fisiológica de semilla y en invernadero el vigor de plántula en cama de arena. Al fraccionar el fertilizante-N en 30-70-00 y 33-33-33 se incrementó la cantidad de semillas m2, observando mayores rendimientos en la producción de trigo en comparación con la fertilización-N recomendada de 50-50-00 que actualmente se utiliza. Los mejores porcentajes de emergencia se presentaron en los fraccionamientos 33-33-33, 30-70-00 y 70-30-00. Con relación a los índices de vigor IV-I y IV-II, el tratamiento que mostro los valores mayores fue 30-70-00. El FFN en el que se observaron los mejores resultados tanto en las variables de rendimiento, calidad fisiológica de semilla y vigor de plántula fue 30-70-00.
Total Cholesterol Level of Hypercholesterolemia Male Wistar Rats (Rattus norvegicus) with Ethanol Extracts of Purple Sweet Potato Leaf (Ipomoea batatas (L.) Lam)
Authors: Fatimah Siti , Arisandi Desto , Saputri Meirina Sindi
Published: April 2018

The increase in total cholesterol level increases the risk of cardiovascular disease. Sweet potato leaves are a food that contains polyphenols, flavonoids, quercetin, tannin, and fiber that effectively lower total cholesterol levels. This study aims to analyze the effect of ethanol extracts of leaf purple sweet potato on serum total cholesterol levels of rats fed a high-fat diet. An experimental study with design pre and posttest carried out on 10 male Wistar rats (Rattus norvegicus) fed a high-fat, which are 2 groups: 1 group the control hypercholesterolemia and 1 group ethanol extracts of leaf purple sweet potato. Dose based on leaves of quercetin that is equal to 2 mg/kgBB. The average content of quercetin ethanol extracts of leaf purple sweet potato was analyzed to obtain 14,08 mg/100g. Ethanol extracts of leaf purple sweet potato are given for 14 days by way of on the sonde. Serum total cholesterol was determined by the CHOD-PAP method. The data obtained were analyzed descriptively.The result of this study obtained the average total cholesterol level of white blood rats before giving ethanol extracts of leaf purple sweet potato that is 189,89 mg/dl, whereas after administration of ethanol extracts of leaf purple sweet potato dose 2 mg/kgBB that is 131,92 mg/dl. The decrease in total cholesterol level of white rats after giving ethanol extracts of leaf purple sweet potato with dose 2 mg/kgBB that is 30,52 %.
TEKNOLOGI PROSES BIO OIL DARI MIKROALGA SEBAGAI ENERGI ALTERNATIF
Authors: Uzwatania Fina
Published: April 2018

Seiring dengan perkembangan peradaban manusia, tingkat kebutuhan energi manusia juga semakin meningkat. Pemenuhan energi di dunia sebagian besar dihasilkan dari pembakaran bahan bakar fosil yang sudah berumur jutaan tahun berupa bahan yang tidak dapat diperbaharui, dan hanya sebagian kecil yang berasal dari penggunaan sumber energi lain yang berasal dari bahan terbarukan.  Salah satu contoh energi terbarukan yang dapat dikembangkan diantaranya adalah energi biomassa dari mikroalga sebagai bahan baku alternatif penghasil bio oil. Bio oil merupakan salah satu energi alternatif yang potensial dan belum banyak dikembangkan terutama di Indonesia. Produksi bio oil dapat menghasilkan keuntungan karena konversi bio oil akan menghasilkan beberapa produk berupa bahan bakar, misalnya: biokerosene, biodiesel, arang, gas dan lain sebagainya. Teknologi proses untuk memproduksi bio oil dari mikroalga dimulai dari proses kultivasi, pemanenan, pengeringan dan pirolisis. Pirolisis merupakan penguraian biomassa karena panas pada suhu lebih dari 150 ºC. Hasil proses pirolisis ini berupa cairan, gas, dan padatan.
KERIPIK SIMULASI EKSTRAK DAUN CINCAU HIJAU (Premna oblongifolia Merr.,)
Authors: Loka Hendri Hendra
Published: April 2018

Daun Cincau sering dimanfaatkan menjadi aneka minuman. Untuk menambah jenis olahan pangan berbahan baku daun cincau ini dilakukan pembuatan keripik simulasi ekstrak daun cincau. Tujuan penelitian ini adalah mengetahui pengaruh perbandingan ekstrak daun cincau, tapioka dan terigu pada pembuatan keripik simulasi ekstrak daun cincau hijau, mengetahui formulasi keripik simulasi ekstrak daun cincau hijau dan mengetahui kandungan zat gizi, jumlah kalori dan kandungan antioksidan produk terpilih. Keripik simulasi ini dibuat dengan empat perbandingan (Ekstrak Daun cincau hijau : Tepung Tapioka : Tepung Terigu) yaitu 0:40:30, 30:40:30, 35:35:40, 40:30:30 dengan dua kali ulangan. Analisis yang dilakukan meliputi organoleptik (uji mutu sensori dan rating hedonik), uji kandungan antioksidan, dan nilai gizi untuk keripik simulasi terpilih. Perbandingan ekstrak daun cincau hijau, tapioka dan terigu pada keripik simulasi ekstrak daun cincau hijau berpengaruh terhadap sifat organoleptik keripik simulasi. Keripik Simulasi ekstrak daun cincau hijau yang terpilih adalah keripik simulasi pada formula A4 (40:30:30),  memiliki kadar air 1,78 %, abu 1,78 %, lemak 10,68%, protein 9,08%, karbohidrat 76,67% , nilai energi 439,12 Kkal /100g sampel dan antioksidan 25,1 mg vit C / 100g sampel.
Present Scenario Of Derivative Market In India : An Analysis (2010-2018)
Authors: Bindal Meenakshi
Published: April 2018

Derivative market has an important role to play in economic development of a country. Change in exchange rates, interest rates and stock prices of different financial markets have increased the financial risk to the corporate world. Adverse changes in the macroeconomic factors have even threatened the very survival of business world. It is therefore necessary to develop a set of new financial instruments known as derivatives in the Indian financial markets, to manage such risk. The objectives of these instruments is to provide commitments to prices for future dates for giving protection against adverse movements in future prices, in order to reduce the extent of financial risks. This paper traces the growth and current position of India derivative market.
The present study is an effort to analyze derivative trading in india. It is an effort to demonstrate the growth and expansion of financial derivative of NSE in India the time period i,e 2010-2011 to 2017-18.The market turnover has grown from Rs.17663664.57 Cr. in 2009-2010 to 1163539816.124 Cr. in 2017-18.
Inducing Strong Non-Linearities in a Phonon Trapping Quartz Bulk Acoustic Wave Resonator Coupled to a Superconducting Quantum Interference Device
Authors: Goryachev Maxim , Ivanov Eugene , Galliou Serge , Tobar Michael
Published: April 2018

A quartz Bulk Acoustic Wave resonator is designed to coherently trap phonons in such a way that they are well confined and immune to suspension losses so they exhibit extremely high acoustic Q-factors at low temperature, with Q × f products of order 10 18 Hz. In this work we couple such a resonator to a Superconducting Quantum Interference Device (SQUID) amplifier and investigate effects in the strong signal regime. Both parallel and series connection topologies of the system are investigated. The study reveals significant non-Duffing response that is associated with the nonlinear characteristics of Josephson junctions. The nonlinearity provides quasi-periodic structure of the spectrum in both incident power and frequency. The result gives an insight into the open loop behaviour of a future Cryogenic Quartz Oscillator in the strong signal regime.
Fabrication and Characterization of Medical Mesh-Nebulizer for Aerosol Drug Delivery
Authors: Choi Kyong-Hoon , Moon Sang-Hyub , Park Su-Kang , Cho Guangsup , Nam Ki , Park Bong
Published: April 2018

In the field of drug delivery, a nebulizer is a device used to convert liquid drugs into tiny airborne droplets, such as aerosol or a mist form. These fine droplets are delivered to a patient’s lungs and airways and then spread throughout the body via blood vessels. Therefore, nebulization therapy is a highly-effective method compared with existing drug delivery methods. To enhance the curative influence of a drug, this study suggests the use of a new micro-porous mesh nebulizer consisting of a controllable palladium–nickel (Pd–Ni) membrane filter, piezoelectric element, and a cavity in the micro-pump. In this research, we optimize a biocompatible Pd–Ni membrane filter, such that it generated the smallest aerosol particles of various drugs. The pore size of the filter outlet is 4.2 μm ± 0.15 μm and the thickness of the Pd-Ni membrane filter is approximately 41.5 μm. In addition, the Pd–Ni membrane filter has good biocompatibility with normal cells. The result of a spray test with deionized (DI) water indicated that the size of a standard liquid droplet is 4.53 μm. The device has an electrical requirement, with a low power consumption of 2.5 W, and an optimal operation frequency of 98.5 kHz.
Study of the Electromagnetic Properties of Nano (MxZn1−x)Fe2O4 (M=Cu, Ni) as a Function of the Sintering Temperature
Authors: Liu Yenchun , Hsu Jarnchih
Published: April 2018

In this study, the chemical co-precipitation method was used to prepare a nanoscale ferrite powder with Cu-Zn and Ni-Zn compositions. Ferrite, in different Cu-Zn stoichiometric ratios, showed optimal composition of saturated magnetization for Cu0.7Zn0.3Fe2O4; under an air environment and calcined at 900 °C, the saturated magnetization was 60.19 M(emu/g). The average particle diameter was 10 nm for the non-calcined sample, while when the sintering temperature was 900 °C, the particle diameter was about 150 nm. In addition, in different Ni-Zn stoichiometric ratios, the optimal composition of the saturated magnetization was Ni0.5Zn0.5Fe2O4; under an air environment and calcination at 900 °C, the saturated magnetization was 91.40 M(emu/g). The average particle diameter for the non-calcined sample was about 10 nm, but when the sintering temperature was 1200 °C, the particle diameter was 201.06 nm. The prepared ferrite nano-powder was characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), and vibrating sample magnetometer(VSM) to reveal its microscopic structure and related electromagnetic properties. Ferrite powders of either Cu-Zn or Ni-Zn composition can be used as catalysts for chemical reactions or iron core materials.
Gas-Phase Phosphorous Poisoning of a Pt/Ba/Al2O3 NOx Storage Catalyst
Authors: Jonsson Rasmus , Mihai Oana , Woo Jungwon , Skoglundh Magnus , Olsson Eva , Berggrund Malin , Olsson Louise
Published: April 2018

The effect of phosphorous exposure on the NOx storage capacity of a Pt/Ba/Al2O3 catalyst coated on a ceramic monolith substrate has been studied. The catalyst was exposed to phosphorous by evaporating phosphoric acid in presence of H2O and O2. The NOx storage capacity was measured before and after the phosphorus exposure and a significant loss of the NOx storage capacity was detected after phosphorous exposure. The phosphorous poisoned samples were characterized by X-ray photoelectron spectroscopy (XPS), environmental scanning electron microscopy (ESEM), N2-physisorption and inductive coupled plasma atomic emission spectroscopy (ICP-AES). All characterization methods showed an axial distribution of phosphorous ranging from the inlet to the outlet of the coated monolith samples with a higher concentration at the inlet of the samples. Elemental analysis, using ICP-AES, confirmed this distribution of phosphorous on the catalyst surface. The specific surface area and pore volume were significantly lower at the inlet section of the monolith where the phosphorous concentration was higher, and higher at the outlet where the phosphorous concentration was lower. The results from the XPS and scanning electron microscopy (SEM)-energy dispersive X-ray (EDX) analyses showed higher accumulation of phosphorus towards the surface of the catalyst at the inlet of the monolith and the phosphorus was to a large extent present in the form of P4O10. However, in the middle section of the monolith, the XPS analysis revealed the presence of more metaphosphate (PO3−). Moreover, the SEM-EDX analysis showed that the phosphorous to higher extent had diffused into the washcoat and was less accumulated at the surface close to the outlet of the sample.
A Decentralized Receiver in Gaussian Interference
Authors: Chapman Christian , Mittelmann Hans , Margetts Adam , Bliss Daniel
Published: April 2018

Bounds are developed on the maximum communications rate between a transmitter and a fusion node aided by a cluster of distributed receivers with limited resources for cooperation, all in the presence of an additive Gaussian interferer. The receivers cannot communicate with one another and can only convey processed versions of their observations to the fusion center through a Local Array Network (LAN) with limited total throughput. The effectiveness of each bound’s approach for mitigating a strong interferer is assessed over a wide range of channels. It is seen that, if resources are shared effectively, even a simple quantize-and-forward strategy can mitigate an interferer 20 dB stronger than the signal in a diverse range of spatially Ricean channels. Monte-Carlo experiments for the bounds reveal that, while achievable rates are stable when varying the receiver’s observed scattered-path to line-of-sight signal power, the receivers must adapt how they share resources in response to this change. The bounds analyzed are proven to be achievable and are seen to be tight with capacity when LAN resources are either ample or limited.
On the Evolution and Application of the Thermal Network Method for Energy Assessments in Buildings
Authors: Bagheri Ali , Feldheim Véronique , Ioakimidis Christos
Published: April 2018

This paper describes the evolution of the thermal network and its applications for making simplified thermal models of buildings by means of thermal resistances (R) and capacitances (C). In the literature, there are several modelling schemes for buildings. Here, we investigate the advantages, disadvantages, and improvements of thermal networks. The thermal network method has been used in different studies for calculating indoor air temperature and heating load, estimating model parameters, and studying building interactions with heating and cooling systems. This review paper conducts an investigation into the application, system identification, and structure of thermal networks compared to other tools. Within the framework of the thermal network method, we conclude with some new proposals for research in this field to expand the idea of the thermal network to other engineering and energy management fields.
Reduction of Electric Power Consumption in CO2-PSA with Zeolite 13X Adsorbent
Authors: Shigaki Nobuyuki , Mogi Yasuhiro , Haraoka Takashi , Sumi Ikuhiro
Published: April 2018

Reduction of CO2 from waste gases from various industries is now desired worldwide. As a technology for separating CO2 from mixed gases, Pressure Swing Adsorption (PSA) is one of the practical processes that are widely used at present owing to the simplicity of its gas separation mechanism. In order to reduce the cost of CO2 separation, a further reduction of the running cost of CO2-PSA operation is required. Among all the utilities used in CO2-PSA, electric power consumption has the greatest impact, especially in cases where the pressure swing range between gas adsorption and gas desorption is large. Electric power consumption increases significantly when the pressure loss inside the adsorber has reached a non-negligible level. Changing the adsorbent pellet size is a convenient method for reducing pressure loss, but its effect on CO2-PSA performance was unclear. Therefore, in this work, the effects of the size of the adsorbent pellets on both the gas adsorption behavior and the electric power consumption in CO2-PSA were evaluated experimentally. From the results of laboratory-scale CO2-PSA experiments and gas adsorption rate measurements, it was observed that the effect of the pellet size appeared only in the early stage of the gas adsorption step and was not dominant when the cycle time was sufficiently long. Subsequently, pilot-scale CO2-PSA experiments with the same CO2 throughput were also conducted, and as a result, the electric power consumption of a vacuum pump was lowered by 15% in case of using d = 3.0 mm larger adsorbent pellets compared to the results with d = 1.5 mm smaller adsorbent pellets.
Multifaceted Role of Pneumolysin in the Pathogenesis of Myocardial Injury in Community-Acquired Pneumonia
Authors: Anderson Ronald , Nel Jan , Feldman Charles
Published: April 2018

Pneumolysin (PLY), a member of the family of Gram-positive bacterial, cholesterol-dependent, β-barrel pore-forming cytolysins, is the major protein virulence factor of the dangerous respiratory pathogen, Streptococcus pneumoniae (pneumococcus). PLY plays a major role in the pathogenesis of community-acquired pneumonia (CAP), promoting colonization and invasion of the upper and lower respiratory tracts respectively, as well as extra-pulmonary dissemination of the pneumococcus. Notwithstanding its role in causing acute lung injury in severe CAP, PLY has also been implicated in the development of potentially fatal acute and delayed-onset cardiovascular events, which are now recognized as being fairly common complications of this condition. This review is focused firstly on updating mechanisms involved in the immunopathogenesis of PLY-mediated myocardial damage, specifically the direct cardiotoxic and immunosuppressive activities, as well as the indirect pro-inflammatory/pro-thrombotic activities of the toxin. Secondly, on PLY-targeted therapeutic strategies including, among others, macrolide antibiotics, natural product antagonists, cholesterol-containing liposomes, and fully humanized monoclonal antibodies, as well as on vaccine-based preventive strategies. These sections are preceded by overviews of CAP in general, the role of the pneumococcus as the causative pathogen, the occurrence and types of CAP-associated cardiac complication, and the structure and biological activities of PLY.
Pathways of Dissipation of Frictional Energy under Boundary Lubricated Sliding Wear of Martensitic Materials
Authors: Stemmer Priska , Fischer Alfons
Published: April 2018

The challenges of technical systems subjected to friction and wear become more demanding with steadily increasing stresses. Besides safety matters, failure of tribologically loaded systems can cause tremendous maintenance costs. Because of the lack of a general wear prediction model, tribometer tests must be used in order to investigate wear behaviour of materials in certain tribological systems. Any well-aimed optimizations of tribological contacts requires a comprehensive understanding of friction and wear mechanisms. Otherwise the transferability into technical applications is questionable because of the wide range of applied loads, lubrication conditions, and materials microstructures. In this study, specimens with different topographies and subsurface microstructures were investigated prior to and after tribological testing. The analyses of surface and subsurface characteristics were performed by means of complementary high-resolution electron-microscopy techniques. The study attempted to link the findings to the wear behavior in order to gain information about the pathways of dissipation and transformation of frictional energy into wear. It was found that the dissipation pathways of base body and counter body were different, resulting in diverse tribological behaviour. Nonetheless, the presence of a near-surface grain-refined layers (tribomaterial) supported by a sub-surface strain gradient appears to provide a beneficial influence. Despite the fact that any direct or even conclusive relation to the topographies or subsurface microstructures cannot be given, the discussion provides some hints on how to analyse such systems for their characteristic mechanisms. In addition to the capability of such approach as one step of understanding, its limitations are shown and briefly discussed as well.
The Structure of the Lipid A from the Halophilic Bacterium Spiribacter salinus M19-40T
Authors: Barrau Clara , Di Lorenzo Flaviana , Menes Rodolfo , Lanzetta Rosa , Molinaro Antonio , Silipo Alba
Published: April 2018

The study of the adaptation mechanisms that allow microorganisms to live and proliferate in an extreme habitat is a growing research field. Directly exposed to the external environment, lipopolysaccharides (LPS) from Gram-negative bacteria are of great appeal as they can present particular structural features that may aid the understanding of the adaptation processes. Moreover, through being involved in modulating the mammalian immune system response in a structure-dependent fashion, the elucidation of the LPS structure can also be seen as a fundamental step from a biomedical point of view. In this paper, the lipid A structure of the LPS from Spiribacter salinus M19-40T, a halophilic gamma-proteobacteria, was characterized through chemical analyses and matrix-assisted laser desorption ionization (MALDI) mass spectrometry. This revealed a mixture of mono- and bisphosphorylated penta- to tri-acylated species with the uncommon 2 + 3 symmetry and bearing an unusual 3-oxotetradecaonic acid.
Characteristics of Milk Fermented by Streptococcus thermophilus MGA45-4 and the Profiles of Associated Volatile Compounds during Fermentation and Storage
Authors: Dan Tong , Jin Rulin , Ren Weiyi , Li Ting , Chen Haiyan , Sun Tiansong
Published: April 2018

The lactic acid bacterium Streptococcus thermophilus is a major starter culture for the production of dairy products. In this study, the physiochemical characteristics of milk fermented by the MGA45-4 isolate of S. thermophilus were analyzed. Our data indicate that milk fermented using S. thermophilus MGA45-4 maintained a high viable cell count (8.86 log10 colony-forming units/mL), and a relatively high pH (4.4), viscosity (834.33 mPa·s), and water holding capacity (40.85%) during 14 days of storage. By analyzing the volatile compound profile using solid-phase microextraction and gas chromatography/mass spectrometry, we identified 73 volatile compounds in the fermented milk product, including five carboxylic acids, 21 aldehydes, 13 ketones, 16 alcohols, five esters, and 13 aromatic carbohydrates. According to the odor activity values, 11 of these volatile compounds were found to play a key role in producing the characteristic flavor of fermented milk, particularly octanal, nonanal, hexanal, 2,3-butanedione, and 1-octen-3-ol, which had the highest odor activity values among all compounds analyzed. These findings thus provide more insights in the chemical/molecular characteristics of milk fermented using S. thermophilus, which may provide a basis for improving dairy product flavor/odor during the process of fermentation and storage.
Free and Bound Phenolic Compound Content and Antioxidant Activity of Different Cultivated Blue Highland Barley Varieties from the Qinghai-Tibet Plateau
Authors: Yang Xi-Juan , Dang Bin , Fan Ming-Tao
Published: April 2018

In this study, the polyphenols composition and antioxidant properties of 12 blue highland barley varieties planted on the Qinghai-Tibet Plateau area were measured. The contents of the free, bound and total phenolic acids varied between 166.20–237.60, 170.10–240.75 and 336.29–453.94 mg of gallic acid equivalents per 100 g of dry weight (DW) blue highland barley grains, while the free and bound phenolic acids accounted for 50.09% and 49.91% of the total phenolic acids, respectively. The contents of the free, bound and total flavones varied among 20.61–25.59, 14.91–22.38 and 37.91–47.98 mg of catechin equivalents per 100 g of dry weight (DW) of blue highland barley grains, while the free and bound flavones accounted for 55.90% and 44.10% of the total flavones, respectively. The prominent phenolic compounds in the blue hulless barley grains were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, naringenin, hesperidin, rutin, (+)-catechin and quercetin. Among these, protocatechuic acid, chlorogenic acid and (+)-catechin were the major phenolic compounds in the free phenolics extract. The most abundant bound phenolics were gallic acid, benzoic acid, syringic acid, 4-coumaric acid, benzoic acid, dimethoxybenzoic acid, naringenin, hesperidin, quercetin and rutin. The average contribution of the bound phenolic extract to the DPPH• free radical scavenging capacity was higher than 86%, that of free phenolic extract to the ABTS•+ free radical scavenging capacity was higher than 79%, and that of free phenolic (53%) to the FRAP antioxidant activity was equivalent to that of the bound phenol extract (47%). In addition, the planting environment exerts a very important influence on the polyphenol composition, content and antioxidant activity of blue highland barley. The correlation analysis showed that 2,4-hydroxybenzoic acid and protocatechuic acid were the main contributors to the DPPH• and ABTS•+ free radical scavenging capacity in the free phenolic extract, while chlorogenic acid, vanillic acid, ferulic acid and quercetin were the main contributors to the free radical scavenging capacity in the bound phenol extract. The study results show that the blue highland barley grains have rich phenolic compounds and high antioxidant activity, as well as significant varietal differences. The free and bound phenolic extracts in the blue hulless barley grains have an equivalent proportion in the total phenol, and co-exist in two forms. They can be used as a potential valuable source of natural antioxidants, and can aid in enhancing the development and daily consumption of foods relating to blue highland barley.
Systematic Analysis of the Pleurotus ostreatus Laccase Gene (PoLac) Family and Functional Characterization of PoLac2 Involved in the Degradation of Cotton-Straw Lignin
Authors: Jiao Xiaoyu , Li Guoqing , Wang Yan , Nie Fan , Cheng Xi , Abdullah Muhammad , Lin Yi , Cai Yongping
Published: April 2018

Fungal laccases play important roles in the degradation of lignocellulose. Although some PoLacs have been reported in several studies, still no comprehensive bioinformatics study of the LAC family in Pleurotus ostreatus has been reported. In this study, we identified 12 laccase genes in the whole genome sequence of P. ostreatus and their physical characteristics, gene distribution, phylogenic relationships, gene structure, conserved motifs, and cis-elements were also analyzed. The expression patterns of 12 PoLac genes at different developmental stages and under different culture substrates were also analyzed. The results revealed that PoLac2 and PoLac12 may be involved in the degradation of lignin and the formation of the fruiting body, respectively. Subsequently, we overexpressed PoLac2 in P. ostreatus by the Agrobacterium tumefaciens-mediated transformation (ATMT) method. The transformants’ laccase activity increased in varying degrees, and the gene expression level of PoLac2 in transformants was 2–8 times higher than that of the wild-type strain. Furthermore, the lignin degradation rate by transgenic fungus over 30 days was 2.36–6.3% higher than that of wild-type. Our data show that overexpression of PoLac2 significantly enhanced the lignin degradation of cotton-straw. To our knowledge, this study is the first report to demonstrate the functions of PoLac2 in P. ostreatus.
Preconcentration of Trace Neonicotinoid Insecticide Residues Using Vortex-Assisted Dispersive Micro Solid-Phase Extraction with Montmorillonite as an Efficient Sorbent
Authors: Moyakao Khwankaew , Santaladchaiyakit Yanawath , Srijaranai Supalax , Vichapong Jitlada
Published: April 2018

In this work, we investigated montmorillonite for adsorption of neonicotinoid insecticides in vortex-assisted dispersive micro-solid phase extraction (VA-d-μ-SPE). High-performance liquid chromatography with photodiode array detection was used for quantification and determination of neonicotinoid insecticide residues, including thiamethoxam, clothianidin, imidacloprid, acetamiprid, and thiacloprid. In this method, the solid sorbent was dispersed into the aqueous sample solution and vortex agitation was performed to accelerate the extraction process. Finally, the solution was filtered from the solid sorbent with a membrane filter. The parameters affecting the extraction efficiency of the proposed method were optimized, such as amount of sorbent, sample volume, salt addition, type and volume of extraction solvent, and vortex time. The adsorbing results show that montmorillonite could be reused at least 4 times and be used as an effective adsorbent for rapid extraction/preconcentration of neonicotinoid insecticide residues. Under optimum conditions, linear dynamic ranges were achieved between 0.5 and 1000 ng mL−1 with a correlation of determination (R2) greater than 0.99. Limit of detection (LOD) ranged from 0.005 to 0.065 ng mL−1, while limit of quantification (LOQ) ranged from 0.008 to 0.263 ng mL−1. The enrichment factor (EF) ranged from 8 to 176-fold. The results demonstrated that the proposed method not only provided a more simple and sensitive method, but also can be used as a powerful alternative method for the simultaneous determination of insecticide residues in natural surface water and fruit juice samples.
Maternal Melatonin Therapy Attenuated Maternal High-Fructose Combined with Post-Weaning High-Salt Diets-Induced Hypertension in Adult Male Rat Offspring
Authors: Tain You-Lin , Leu Steve , Lee Wei-Chia , Wu Kay , Chan Julie
Published: April 2018

Consumption of food high in fructose and salt is associated with the epidemic of hypertension. Hypertension can originate from early life. Melatonin, a pleiotropic hormone, regulates blood pressure. We examined whether maternal melatonin therapy can prevent maternal high-fructose combined with post-weaning high-salt diet-induced programmed hypertension in adult offspring. Pregnant Sprague-Dawley rats received either a normal diet (ND) or a 60% fructose diet (HF) during pregnancy and the lactation period. Male offspring were on either the ND or a high-salt diet (HS, 1% NaCl) from weaning to 12 weeks of age and were assigned to five groups (n = 8/group): ND/ND, HF/ND, ND/HS, HF/HS, and HF/HS+melatonin. Melatonin (0.01% in drinking water) was administered during pregnancy and lactation. We observed that maternal HF combined with post-weaning HS diets induced hypertension in male adult offspring, which was attenuated by maternal melatonin therapy. The beneficial effects of maternal melatonin therapy on HF/HS-induced hypertension related to regulating several nutrient-sensing signals, including Sirt1, Sirt4, Prkaa2, Prkab2, Pparg, and Ppargc1a. Additionally, melatonin increased protein levels of mammalian targets of rapamycin (mTOR), decreased plasma asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine levels, and increased the l-arginine-to-ADMA ratio. The reprogramming effects by which maternal melatonin therapy protects against hypertension of developmental origin awaits further elucidation.
The Association of Dietary Patterns with High-Risk Human Papillomavirus Infection and Cervical Cancer: A Cross-Sectional Study in Italy
Authors: Barchitta Martina , Maugeri Andrea , Quattrocchi Annalisa , Agrifoglio Ottavia , Scalisi Aurora , Agodi Antonella
Published: April 2018

Specific foods and nutrients help prevent the progression of persistent high-risk human papillomavirus (hrHPV) infection to cervical cancer (CC). The aim of this study was to investigate dietary patterns which may be associated with hrHPV status and the risk of high-grade cervical intraepithelial neoplasia (CIN2+). Overall, 539 eligible women, including 127 with CIN2+, were enrolled in a cross-sectional study, and tested for hrHPV infection. Food intake was estimated using a food frequency questionnaire. Logistic regression models were applied. Using the Mediterranean Diet Score, we demonstrated that, among 252 women with a normal cervical epithelium, medium adherence to the Mediterranean diet decreased the odds of hrHPV infection when compared to low adherence (adjOR = 0.40, 95%CI = 0.22–0.73). Using the principal component analysis, we also identified two dietary patterns which explained 14.31% of the variance in food groups intake. Women in the third and fourth quartiles of the “Western pattern” had higher odds of hrHPV infection when compared with first quartile (adjOR = 1.77, 95% CI = 1.04–3.54 and adjOR = 1.97, 95%CI = 1.14–4.18, respectively). Adjusting for hrHPV status and age, women in the third quartile of the “prudent pattern” had lower odds of CIN2+ when compared with those in the first quartile (OR = 0.50, 95%CI = 0.26–0.98). Our study is the first to demonstrate the association of dietary patterns with hrHPV infection and CC and discourages unhealthy habits in favour of a Mediterranean-like diet.
Ecological Impact of Forest Fires and Subsequent Restoration in Chile
Authors: Valderrama Luz , Contreras-Reyes Javier , Carrasco Raúl
Published: April 2018

This note analyzes the effects forest fires in Chile have on vegetation and subsequent ecological restoration. We analyze why forest fires have been a main factor that affects the environment and causes the ecosystem to deteriorate, leading to loss of native forests, species extinction, damage to the urban population, and others. The data examined are derived from fire hotspots in Chile’s central and central-south zones ( 33 ∘ 00 ′ S– 41 ∘ 57 ′ S) between 1985 and 2017. We also analyze some key aspects for restoration priorities such as studying affected areas and posterior consequences. Finally, we evaluate actions the country has already taken, and propose further appropriate preventive and restoration measures.
Multivariate Credibility in Bonus-Malus Systems Distinguishing between Different Types of Claims
Authors: Gómez-Déniz Emilio , Calderín-Ojeda Enrique
Published: April 2018

In the classical bonus-malus system the premium assigned to each policyholder is based only on the number of claims made without having into account the claims size. Thus, a policyholder who has declared a claim that results in a relatively small loss is penalised to the same extent as one who has declared a more expensive claim. Of course, this is seen unfair by many policyholders. In this paper, we study the factors that affect the number of claims in car insurance by using a trivariate discrete distribution. This approach allows us to discern between three types of claims depending wether the claims are above, between or below certain thresholds. Therefore, this model implements the two fundamental random variables in this scenario, the number of claims as well as the amount associated with them. In addition, we introduce a trivariate prior distribution conjugated with this discrete distribution that produce credibility bonus-malus premiums that satisfy appropriate traditional transition rules. A practical example based on real data is shown to examine the differences with respect to the premiums obtained under the traditional system of tarification.
Non-Invasive Blood Pressure Estimation from ECG Using Machine Learning Techniques
Authors: Simjanoska Monika , Gjoreski Martin , Gams Matjaž , Madevska Bogdanova Ana
Published: April 2018

Background: Blood pressure (BP) measurements have been used widely in clinical and private environments. Recently, the use of ECG monitors has proliferated; however, they are not enabled with BP estimation. We have developed a method for BP estimation using only electrocardiogram (ECG) signals. Methods: Raw ECG data are filtered and segmented, and, following this, a complexity analysis is performed for feature extraction. Then, a machine-learning method is applied, combining a stacking-based classification module and a regression module for building systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP) predictive models. In addition, the method allows a probability distribution-based calibration to adapt the models to a particular user. Results: Using ECG recordings from 51 different subjects, 3129 30-s ECG segments are constructed, and seven features are extracted. Using a train-validation-test evaluation, the method achieves a mean absolute error (MAE) of 8.64 mmHg for SBP, 18.20 mmHg for DBP, and 13.52 mmHg for the MAP prediction. When models are calibrated, the MAE decreases to 7.72 mmHg for SBP, 9.45 mmHg for DBP and 8.13 mmHg for MAP. Conclusion: The experimental results indicate that, when a probability distribution-based calibration is used, the proposed method can achieve results close to those of a certified medical device for BP estimation.
Label-Free QCM Immunosensor for the Detection of Ochratoxin A
Authors: Pirinçci Şerife , Ertekin Özlem , Laguna Duygu , Özen Fehime , Öztürk Zafer , Öztürk Selma
Published: April 2018

Ochratoxin A (OTA) is a potent mycotoxin that poses a risk in food and feed moieties and subject to worldwide regulation. Laboratory-based analytical methods are traditionally employed for reliable OTA quantification, but these methods cannot provide rapid and on-site analysis, where biosensors fill this gap. In this study a label-free quartz crystal microbalance (QCM)-based immunosensor for the detection of OTA, which is one of the most important small molecule contaminants, was developed by direct immobilization of OTA to amine-bearing sensor surfaces using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC)/N-Hydroxysuccinimide (NHS) chemistry. The protein-free sensor surface enabled regeneration of sensor surface with 50 mM NaOH and 1% SDS up to 13 times without loss of performance, which would disrupt a protein-containing sensor surface. We developed a QCM immunosensor using the developed sensor surface with a 17.2–200 ng/mL detection range which can be used for on-site detection of feedstuffs.
A Novel “Off-On” Fluorescent Probe Based on Carbon Nitride Nanoribbons for the Detection of Citrate Anion and Live Cell Imaging
Authors: Hu Yanling , Yang Dongliang , Yang Chen , Feng Ning , Shao Zhouwei , Zhang Lei , Wang Xiaodong , Weng Lixing , Luo Zhimin , Wang Lianhui
Published: April 2018

A novel fluorescent “off-on” probe based on carbon nitride (C3N4) nanoribbons was developed for citrate anion (C6H5O73−) detection. The fluorescence of C3N4 nanoribbons can be quenched by Cu2+ and then recovered by the addition of C6H5O73−, because the chelation between C6H5O73− and Cu2+ blocks the electron transfer between Cu2+ and C3N4 nanoribbons. The turn-on fluorescent sensor using this fluorescent “off-on” probe can detect C6H5O73− rapidly and selectively, showing a wide detection linear range (1~400 μM) and a low detection limit (0.78 μM) in aqueous solutions. Importantly, this C3N4 nanoribbon-based “off-on” probe exhibits good biocompatibility and can be used as fluorescent visualizer for exogenous C6H5O73− in HeLa cells.
Variation in Ecosystem Service Values in an Agroforestry Dominated Landscape in Ethiopia: Implications for Land Use and Conservation Policy
Authors: Temesgen Habtamu , Wu Wei , Shi Xiaoping , Yirsaw Eshetu , Bekele Belewu , Kindu Mengistie
Published: April 2018

Human pressure on a rugged and fragile landscape can cause land use/cover changes that significantly alter the provision of ecosystem services. Estimating the multiple services, particularly those obtained from agroforestry systems, is seldom attempted. A combined approach of geospatial technology, cross-sectional field investigations, and economic valuation of natural capital was used to develop an ecosystem service valuation (ESV) model to estimate changes in ESV between 1986 and 2015 in southern Ethiopia. Over 120 values were sourced, mainly from an ecosystem service valuation database and allied sources, to establish value coefficients via benefit transfer method. Our 1848 km2 study landscape, with eight land use categories, yielded an annual total ESV of $129 × 106 in 1986 and $147 × 106 in 2015, a 14.2% ($18.3 million) increase in three decades, showing its relative resilience. Yet we observed losses of natural vegetation classes whose area and/or value coefficients were too small to offset their increased value from expanding agroforestry and wetland/marshes, which have the largest cover share and highest economic value, respectively. Appreciating the unique features of agroforests, we strongly recommend that their economic value is studied as a separate ecosystem for further valuation accuracy improvement.
Maslow Portfolio Selection for Individuals with Low Financial Sustainability
Authors: Li Zongxin , Li Xinge , Hui Yongchang , Wong Wing-Keung
Published: April 2018

In this paper, we extend Maslow’s need hierarchy theory and the two-level optimization approach by developing the framework of the Maslow portfolio selection model (MPSM) by solving the two optimization problems to meet the need of individuals with low financial sustainability who prefer to satisfy their lower-level (safety) need first, and, thereafter, look for higher-level (self-actualization) need to maximize the optimal return. We illustrate our proposed model with real American stock data from the S&P index and conduct the out-of-sample analysis to compare the performance of our proposed Variance-CVaR (conditional value-at-risk) MPSM with both traditional mean-variance and mean-CVaR models. Our empirical analysis shows that our proposed Variance-CVaR MPSM is not only sustainable, but also obtains the best out-of-sample performance in the sense that the optimal portfolios obtained by using our proposed Variance-CVaR MPSM obtain the highest cumulative returns in the out-of-sample period among the models used in our paper. We note that our proposed model is not only suitable to individuals with low financial sustainability, but also suitable to institutions or investors with high financial sustainability.
Solar Energy Resource Analysis and Evaluation of Photovoltaic System Performance in Various Regions of Saudi Arabia
Authors: Awan Ahmed , Zubair Muhammad , P. Praveen , Abokhalil Ahmed
Published: April 2018

According to Vision 2030, the Kingdom of Saudi Arabia (K.S.A) plans to harness 9.5 GW of energy from renewable energy sources, which includes a major part of solar PV generation. This massive implementation of solar projects requires an accurate assessment and analysis of solar resource data and PV site selection. This paper presents a detailed analysis of one-year solar radiation data and energy output of 100 kW PV systems at 44 different locations across the K.S.A. Coastal areas have a lower amount of global horizontal irradiance (GHI) as compared to inland areas. Najran University station gives the highest annual electrical output of 172,083 kWh, yield factor of 1721, and capacity utilization factor of 19.6%. Sharurah and Timma TVTC are second and third best with respect to annual PV performance. Similarly, during high load summer season (April–October), Tabuk station is the best location for a PV power plant with an electrical output of 110,250 kWh, yield factor of 1102, and capacity utilization factor of 21.46%. Overall, the northern province of Tabuk is the most feasible region for a solar PV plant. The basic approach presented in this research study compares solar resource pattern and solar PV system output pattern with the load profile of the country. The site selected based on this criterion is recommended to be economically most feasible which can reduce the stress on electricity companies during high load seasons by clipping the peak load during daytime in the hot summer period.