bluuebunny/crossref_metadata_2025 huggingface dataset:
Variação nas concentrações de compostos fenólicos e nas taxas de herbivoria em Aspidosperma pyrifolium Mart. em áreas antropizadas de Caatinga
Authors: Aquino Ranilson Emmanuel , Falcão Hiram Marinho , Almeida-Cortez Jarcilene Silva
Published: March 2017

Disponibilidade de recursos e perturbações antrópicas possuem relevância nas respostas à atuação dos herbívoros. Ao longo da evolução as plantas desenvolveram estratégias de defesa contra a herbivoria, como as defesas químicas. O objetivo deste trabalho foi analisar a relação entre as taxas de herbivoria e caracteres biométricos de Aspidosperma pyrifolium Mart, e o conteúdo foliar de compostos fenólicos/taninos, em áreas de Caatinga, com e sem perturbações antrópicasna microrregião de Itaparica, Pernambuco. Foram realizadas medidas de taxa de herbivoria, biometria,e conteúdo de carbono, nitrogênio e compostos fenólicos/taninos. Os dados foram analisados através de ANOVA fatorial seguida de teste de Tukey (5%), e análises correlação e regressão linear simples. Os parâmetros biométricos não apresentaram diferenças entre as áreas, nem relação com o conteúdo de compostos fenólicos. Os conteúdos de nitrogênio foram maiores no mês mais seco, enquanto os de carbono foram maiores no fim da estação chuvosa. Concentrações de compostos fenólicos/taninos tiveram relação negativa com as taxas de herbivoria das áreas impactadas, mas nas áreas preservadas essa relação não foi observada. O consumo prévio das folhas por caprinos pode ter estimulado o aumento na produção de compostos de defesa nas áreas impactadas, o que ocasionou queda nas taxas de herbivoria por insetos. Já nas áreas preservadas a diminuição significativa da herbivoria em Junho pode estar ligada ao fim do ciclo de crescimento de alguns invertebrados Embora a influência da pecuária extensiva possa ser notada em áreas impactadas ela não pode ser considerada a causa única da relação herbivoria/produção de compostos fenólicos.
Changes in Carbon Cycling during Development of Successional Agroforestry
Authors: Selecky Tomas , Bellingrath-Kimura Sonoko , Kobata Yuji , Yamada Masaaki , Guerrini Iraê , Umemura Helio , Dos Santos Dinaldo
Published: March 2017

Successional agroforestry systems (SAFS) mimic the structure of natural forests while providing economical outputs. This study clarifies how carbon cycling and carbon sequestration change during successional development of SAFS. In Brazil, three successional stages of SAFS, 6, 12, and 34 years old, were compared in terms of carbon balance. Aboveground biomass, fruit harvest, litterfall, soil respiration, and soil organic carbon were measured for two years and analyzed. Carbon sequestration expressed by net primary productivity increased with age of SAFS from 9.8 Mg·C·ha−1·year−1 in 6-year-old system to 13.5 Mg·C·ha−1·year−1 in 34-year-old system. Accumulation of plant biomass and increased internal carbon cycling in SAFS led to an intensive sequestration of carbon. SAFS can be a sustainable way of agricultural production on vulnerable tropical soils.
Biosynthesis of Sulfur-Containing tRNA Modifications: A Comparison of Bacterial, Archaeal, and Eukaryotic Pathways
Authors: Čavužić Mirela , Liu Yuchen
Published: March 2017

Post-translational tRNA modifications have very broad diversity and are present in all domains of life. They are important for proper tRNA functions. In this review, we emphasize the recent advances on the biosynthesis of sulfur-containing tRNA nucleosides including the 2-thiouridine (s2U) derivatives, 4-thiouridine (s4U), 2-thiocytidine (s2C), and 2-methylthioadenosine (ms2A). Their biosynthetic pathways have two major types depending on the requirement of iron–sulfur (Fe–S) clusters. In all cases, the first step in bacteria and eukaryotes is to activate the sulfur atom of free l-cysteine by cysteine desulfurases, generating a persulfide (R-S-SH) group. In some archaea, a cysteine desulfurase is missing. The following steps of the bacterial s2U and s4U formation are Fe–S cluster independent, and the activated sulfur is transferred by persulfide-carrier proteins. By contrast, the biosynthesis of bacterial s2C and ms2A require Fe–S cluster dependent enzymes. A recent study shows that the archaeal s4U synthetase (ThiI) and the eukaryotic cytosolic 2-thiouridine synthetase (Ncs6) are Fe–S enzymes; this expands the role of Fe–S enzymes in tRNA thiolation to the Archaea and Eukarya domains. The detailed reaction mechanisms of Fe–S cluster depend s2U and s4U formation await further investigations.
More Energy-Efficient CO2 Capture from IGCC GE Flue Gases
Authors: Peampermpool Rakpong , Teh Chii , Tade Moses , Qader Abdul , Barifcani Ahmed
Published: March 2017

Carbon dioxide (CO2) emissions are one of the main reasons for the increase in greenhouse gasses in the earth’s atmosphere and carbon capture and sequestration (CCS) is known as an effective method to reduce CO2 emissions on a larger scale, such as for fossil energy utilization systems. In this paper, the feasibility of capturing CO2 using cryogenic liquefaction and improving the capture rate by expansion will be discussed. The main aim was to design an energy-saving scheme for an IGCC (integrated gasification combined cycle) power plant with CO2 cryogenic liquefaction capture. The experimental results provided by the authors, using the feed gas specification of a 740 MW IGCC General Electric (GE) combustion power plant, demonstrated that using an orifice for further expanding the vent gas after cryogenic capture from 57 bar to 24 bar gave an experimentally observed capture rate up to 65%. The energy-saving scheme can improve the overall CO2 capture rate, and hence save energy. The capture process has also been simulated using Aspen HYSYS simulation software to evaluate its energy penalty. The results show that a 92% overall capture rate can be achieved by using an orifice.
Growth of High Quality Al-Doped CsLiB6O10 Crystals Using Cs2O-Li2O-MoO3 Fluxes
Authors: Zhu Xianchao , Tu Heng , Zhao Ying , Hu Zhanggui
Published: March 2017

Abstract: High quality and large size Al-doped CsLiB6O10 (CLBO) single crystals have been successfully grown by top-seeded solution growth (TSSG) technique using Cs2O–Li2O–MoO3 fluxes. The advantages of this newly developed flux system were investigated by viscosity measurements and growth experiments. Al-doped CLBO presents a very high transmittance in the visible region and the weak absorption values at 1064 nm along a and c axes are only 140 and 50 ppm/cm, respectively. The measured LIDT of Al-doped CLBO at λ = 1064 nm and τ = 5.0 ns is 5.10 GW/cm2. Moreover, Al-doped CLBO exhibits an apparent enhancement of the hygroscopic nature in contrast with the undoped crystal as determined by the humidity experiments. Finally, a high fourth harmonic generation (FHG) conversion efficiency of 63% utilizing Al-doped CLBO has been achieved by a picosecond mode-locked Nd:YAG laser, the results also reveal that Al doping has no obvious impact on the FHG conversion efficiency.
Microstructure Evolution of TiC Particles In Situ, Synthesized by Laser Cladding
Authors: Liu Yanhui , Ding Jieqiong , Qu Weicheng , Su Yu , Yu Zhishui
Published: March 2017

In this paper, a TiC reinforcement metal matrix composite coating is produced using nickel and graphite mixing powder on the surface ofTi-6Al-4V alloy by laser radiation. The microstructure of the coatings is investigated by XRD, SEM and EDS. Results show that most of the TiC phase is granular, with a size of several micrometers, and a few of the TiC phases are petals or flakes. At the cross-section of the coatings, a few special TiC patterns are found and these TiC patterns do not always occur at the observed cross-section. The even distribution of the TiC phase in the coatings confirms that the convection of the laser-melted pool leads to the homogenization of titanium atoms from the molten substrate, and carbon atoms from the preplace powder layer, by the mass transfer. The characteristics of the TiC pattern confirm that the morphology and distribution of the primary TiC phase could be influenced by convection. Two main reasons for this are that the density of the TiC phase is lower than the liquid melt, and that the primary TiC phase precipitates from the pool with a high convection speed at high temperature.
Comparison of Single Ti6Al4V Struts Made Using Selective Laser Melting and Electron Beam Melting Subject to Part Orientation
Authors: Weißmann Volker , Drescher Philipp , Bader Rainer , Seitz Hermann , Hansmann Harald , Laufer Nico
Published: March 2017

The use of additive manufacturing technologies to produce lightweight or functional structures is widespread. Especially Ti6Al4V plays an important role in this development field and parts are manufactured and analyzed with the aim to characterize the mechanical properties of open-porous structures and to generate scaffolds with properties specific to their intended application. An SLM and an EBM process were used respectively to fabricate the Ti6Al4V single struts. For mechanical characterization, uniaxial compression tests and hardness measurements were conducted. Furthermore, the struts were manufactured in different orientations for the determination of the mechanical properties. Roughness measurements and a microscopic characterization of the struts were also carried out. Some parts were characterized following heat treatment (hot isostatic pressing). A functional correlation was found between the compressive strength and the slenderness ratio (λ) as well as the equivalent diameter (d) and the height (L) of EBM and SLM parts. Hardness investigations revealed considerable differences related to the microstructure. An influence of heat treatment as well as of orientation could be determined. In this work, we demonstrate the influence of the fabrication quality of single struts, the roughness and the microstructure on mechanical properties as a function of orientation.
The Polypyrrole/Multiwalled Carbon Nanotube Modified Au Microelectrode for Sensitive Electrochemical Detection of Trace Levels of Pb2+
Authors: Zhu Xuxing , Tong Jianhua , Bian Chao , Gao Chengyao , Xia Shanhong
Published: March 2017

The sensitive detection of trace levels of heavy metal ions such as Pb2+ is of significant importance due to the health hazard they pose. In this paper, we present a polypyrrole (PPy)/multiwalled carbon nanotube (MWCNT)-modified Au microelectrode. The PPy/MWCNT composite film was electrochemically deposited on the microelectrode by cyclic voltammetry (CV). The composite film was investigated by scanning electron microscope (SEM), CV, and electrochemical impedance spectroscopy (EIS), and the results show that this film presents a uniformly distributed and web-like entangled structure and good conductivity. Differential pulse stripping voltammetry (DPSV) was applied to determine trace levels of Pb2+. Experimental conditions including accumulation time and deposition potential were optimized. In optimal conditions, the PPy/MWCNT-modified microelectrode performed sensitive detection of Pb2+ within a concentration range from 1 to 100 μg·L−1, and the limit of detection was 0.65 μg·L−1 at the signal-to-noise ratio of three.
CDC25 Inhibition in Acute Myeloid Leukemia–A Study of Patient Heterogeneity and the Effects of Different Inhibitors
Authors: Brenner Annette , Reikvam Håkon , Rye Kristin , Hagen Karen , Lavecchia Antonio , Bruserud Øystein
Published: March 2017

Cell division cycle 25 (CDC25) protein phosphatases regulate cell cycle progression through the activation of cyclin-dependent kinases (CDKs), but they are also involved in chromatin modulation and transcriptional regulation. CDC25 inhibition is regarded as a possible therapeutic strategy for the treatment of human malignancies, including acute myeloid leukemia (AML). We investigated the in vitro effects of CDC25 inhibitors on primary human AML cells derived from 79 unselected patients in suspension cultures. Both the previously well-characterized CDC25 inhibitor NSC95397, as well as five other inhibitors (BN82002 and the novel small molecular compounds ALX1, ALX2, ALX3, and ALX4), only exhibited antiproliferative effects for a subset of patients when tested alone. These antiproliferative effects showed associations with differences in genetic abnormalities and/or AML cell differentiation. However, the responders to CDC25 inhibition could be identified by analysis of global gene expression profiles. The differentially expressed genes were associated with the cytoskeleton, microtubules, and cell signaling. The constitutive release of 28 soluble mediators showed a wide variation among patients and this variation was maintained in the presence of CDC25 inhibition. Finally, NSC95397 had no or only minimal effects on AML cell viability. In conclusion, CDC25 inhibition has antiproliferative effects on primary human AML cells for a subset of patients, and these patients can be identified by gene expression profiling.
Structural Probing and Molecular Modeling of the A3 Adenosine Receptor: A Focus on Agonist Binding
Authors: Ciancetta Antonella , Jacobson Kenneth
Published: March 2017

Adenosine is an endogenous modulator exerting its functions through the activation of four adenosine receptor (AR) subtypes, termed A1, A2A, A2B and A3, which belong to the G protein-coupled receptor (GPCR) superfamily. The human A3AR (hA3AR) subtype is implicated in several cytoprotective functions. Therefore, hA3AR modulators, and in particular agonists, are sought for their potential application as anti-inflammatory, anticancer, and cardioprotective agents. Structure-based molecular modeling techniques have been applied over the years to rationalize the structure–activity relationships (SARs) of newly emerged A3AR ligands, guide the subsequent lead optimization, and interpret site-directed mutagenesis (SDM) data from a molecular perspective. In this review, we showcase selected modeling-based and guided strategies that were applied to elucidate the binding of agonists to the A3AR and discuss the challenges associated with an accurate prediction of the receptor extracellular vestibule through homology modeling from the available X-ray templates.
Three-Component Reaction of Benzylamines, Diethyl Phosphite and Triethyl Orthoformate: Dependence of the Reaction Course on the Structural Features of the Substrates and Reaction Conditions
Authors: Miszczyk Patrycja , Turowska-Tyrk Ilona , Kafarski Paweł , Chmielewska Ewa
Published: March 2017

The reaction between benzyl amines, triethyl orthoformate, and diethyl phosphite affords either bisphosphonic (compound 1) or N-benzylaminobenzylphosphonic (compound 2) acid depending on the reaction conditions. The final output of the reaction can be manipulated by the choice of reaction conditions, particularly the molar ratio of substrates.
Bovine Colostrum Whey Protein Hydrolysate Inhibits Cell DNA Damage and LDL Oxidation In Vitro
Authors: Chiang Shu-Hua , Wang Shiu-Yu , Chang Chi-Yue , Chen Chih-Wei
Published: March 2017

Whey protein isolated from bovine colostrums collected on the second day postpartum was two-stage hydrolyzed by alcalase and flavourzyme [...]
Optimization of Conditions for Cyanidin-3-OGlucoside (C3G) Nanoliposome Production by Response Surface Methodology and Cellular Uptake Studies in Caco-2 Cells
Authors: Liang Tisong , Guan Rongfa , Shen Haitao , Xia Qile , Liu Mingqi
Published: March 2017

We aimed to optimize the formulation of C3G nanoliposomes using response surface methodology. Additionally, we evaluated the stability, particle change, and encapsulation efficiency (EE) of C3G nanoliposomes under different temperatures and storage durations, as well as in simulated gastrointestinal juice (SGF) and simulated intestinal fluid. The morphology of C3G nanoliposomes was observed by transmission electron microscope. The ability of C3G nanoliposomes to affect cancer cell morphology and inhibit cancer cell proliferation was studied with Caco-2 cells. Reverse-phase evaporation method is a simple and efficient method for liposome preparation. The optimal preparation conditions for this method were as follows: C3G concentration of 0.17 mg/mL, phosphatidylcholine/cholesterol ratio of 2.87, and rotary evaporation temperature of 41.41 °C. At optimal conditions, the particle size and EE of the C3G nanoliposomes were 165.78 ± 4.3 nm and 70.43% ± 1.95%, respectively. The C3G nanoliposomes showed an acceptable stability in SGF at 37 °C for 4 h, but were unstable under extended storage durations and high temperatures. Moreover, our results showed that different concentrations of C3G nanoliposomes affected the morphology and inhibited the proliferation of Caco-2 cells.
Computational Prediction of the Protonation Sites of Ac-Lys-(Ala)n-Lys-NH2 Peptides through Conceptual DFT Descriptors
Authors: Sastre Sebastián , Frau Juan , Glossman-Mitnik Daniel
Published: March 2017

Six density functionals (M11, M11L, MN12L, MN12SX, N12, and N12SX) in connection with the Def2TZVP basis set and the SMD solvation model (water as a solvent) have been assessed for the calculation of the molecular structure and properties of several peptides with the general formulaAc-Lys-(Ala)n-Lys-NH2,withn=0to5  [...]
Nanofibrous Silver-Coated Polymeric Scaffolds with Tunable Electrical Properties
Authors: Memic Adnan , Aldhahri Musab , Tamayol Ali , Mostafalu Pooria , Abdel-wahab Mohamed , Samandari Mohamadmahdi , Moghaddam Kamyar , Annabi Nasim , Bencherif Sidi , Khademhosseini Ali
Published: March 2017

Electrospun micro- and nanofibrous poly(glycerol sebacate)-poly(ε-caprolactone) (PGS-PCL) substrates have been extensively used as scaffolds for engineered tissues due to their desirable mechanical properties and their tunable degradability. In this study, we fabricated micro/nanofibrous scaffolds from a PGS-PCL composite using a standard electrospinning approach and then coated them with silver (Ag) using a custom radio frequency (RF) sputtering method. The Ag coating formed an electrically conductive layer around the fibers and decreased the pore size. The thickness of the Ag coating could be controlled, thereby tailoring the conductivity of the substrate. The flexible, stretchable patches formed excellent conformal contact with surrounding tissues and possessed excellent pattern-substrate fidelity. In vitro studies confirmed the platform’s biocompatibility and biodegradability. Finally, the potential controlled release of the Ag coating from the composite fibrous scaffolds could be beneficial for many clinical applications.
Stirring the Pot: Can Dietary Modification Alleviate the Burden of CKD?
Authors: Snelson Matthew , Clarke Rachel , Coughlan Melinda
Published: March 2017

Diet is one of the largest modifiable risk factors for chronic kidney disease (CKD)-related death and disability. CKD is largely a progressive disease; however, it is increasingly appreciated that hallmarks of chronic kidney disease such as albuminuria can regress over time. The factors driving albuminuria resolution remain elusive. Since albuminuria is a strong risk factor for GFR loss, modifiable lifestyle factors that lead to an improvement in albuminuria would likely reduce the burden of CKD in high-risk individuals, such as patients with diabetes. Dietary therapy such as protein and sodium restriction has historically been used in the management of CKD. Evidence is emerging to indicate that other nutrients may influence kidney health, either through metabolic or haemodynamic pathways or via the modification of gut homeostasis. This review focuses on the role of diet in the pathogenesis and progression of CKD and discusses the latest findings related to the mechanisms of diet-induced kidney disease. It is possible that optimizing diet quality or restricting dietary intake could be harnessed as an adjunct therapy for CKD prevention or progression in susceptible individuals, thereby reducing the burden of CKD.
Exploring the Limits of the Geometric Copolymerization Model
Authors: Engler Martin , Scheubert Kerstin , Schubert Ulrich , Böcker Sebastian
Published: March 2017

The geometric copolymerization model is a recently introduced statistical Markov chain model. Here, we investigate its practicality. First, several approaches to identify the optimal model parameters from observed copolymer fingerprints are evaluated using Monte Carlo simulated data. Directly optimizing the parameters is robust against noise but has impractically long running times. A compromise between robustness and running time is found by exploiting the relationship between monomer concentrations calculated by ordinary differential equations and the geometric model. Second, we investigate the applicability of the model to copolymerizations beyond living polymerization and show that the model is useful for copolymerizations involving termination and depropagation reactions.
MEMS and FOG Technologies for Tactical and Navigation Grade Inertial Sensors—Recent Improvements and Comparison
Authors: Deppe Olaf , Dorner Georg , König Stefan , Martin Tim , Voigt Sven , Zimmermann Steffen
Published: March 2017

In the following paper, we present an industry perspective of inertial sensors for navigation purposes driven by applications and customer needs. Microelectromechanical system (MEMS) inertial sensors have revolutionized consumer, automotive, and industrial applications and they have started to fulfill the high end tactical grade performance requirements of hybrid navigation systems on a series production scale. The Fiber Optic Gyroscope (FOG) technology, on the other hand, is further pushed into the near navigation grade performance region and beyond. Each technology has its special pros and cons making it more or less suitable for specific applications. In our overview paper, we present latest improvements at NG LITEF in tactical and navigation grade MEMS accelerometers, MEMS gyroscopes, and Fiber Optic Gyroscopes, based on our long-term experience in the field. We demonstrate how accelerometer performance has improved by switching from wet etching to deep reactive ion etching (DRIE) technology. For MEMS gyroscopes, we show that better than 1°/h series production devices are within reach, and for FOGs we present how limitations in noise performance were overcome by signal processing. The paper also intends a comparison of the different technologies, emphasizing suitability for different navigation applications, thus providing guidance to system engineers.
Urban Recreational Fisheries in the Australian Coastal Zone: The Sustainability Challenge
Authors: McPhee Daryl
Published: March 2017

Recreational fishing is an important wildlife harvesting activity in urban coastal areas, and recreational harvest in these areas can frequently exceed the commercial harvest. Recreational fishing is a key way that many members of the public experience the environment. The activity enhances social capital, promotes respect for nature, provides health benefits and can provide economic benefits to coastal communities. It is also an important driver of the science on aquatic animals and habitats, and an important tangible reason for many members of the public to conserve and protect aquatic resources. Overall, there has been little specific consideration of urban recreational fisheries management in Australia, despite the paramount importance of urban areas as a focus of recreational fishing activity. This paper identifies that in order to maximize individual and societal benefits from recreational fishing, there needs to be a refocussing of management with the aim of being more holistic. Historically, fisheries management in Australia has focused on maximum sustainable yield (MSY) or maximum economic yield (MEY) which is relevant for the commercial fishing sector, but neither of these is directly relevant to recreational fisheries. This paper identifies that Urban Fisheries Management Plans are required that recognize the specific issues associated with urban recreational fisheries. These plans need to coordinate within and between levels of government and have clear management objectives relevant to urban recreational fisheries. Enhanced opportunities for meaningful citizen science can be incorporated at multiple levels within these plans and this can engender public support for environmental stewardship, as well as fill a very important gap in the knowledge base necessary for managing the activity. As urban recreational fisheries are often occurring in highly modified or degraded habitats, a central element of these plans needs to be habitat restoration and this can have broader benefits for aquatic health. Other management tools include habitat creation (e.g., artificial reefs), optimization of coastal infrastructure as fisheries habitat, and stock enhancement. Overall, Urban Fisheries Management Plans represent a necessary evolution of fisheries management to better address the specific challenges of urban recreational fisheries management, and to best ensure that benefits are optimised.
NEW AGGREGATION OPERATORS FOR DECISION-MAKING UNDER UNCERTAINTY: AN APPLICATIONS IN SELECTION OF ENTREPRENEURIAL OPPORTUNITIES
Authors: BLANCO-MESA Fabio , GIL-LAFUENTE Anna María , MERIGÓ José M.
Published: March 2017

The main aim of this paper is to study how economic environment and logic reasoning guidance the decision-making process to start-up a new business by potential entrepreneurs. The study proposes a new method using the family of selection indices with OWA operator, which allows aggregating information according to the level of importance and their level of objectivity and subjectivity in the same formulation within the decision-making process. To develop case study, we have taken into account some industries of the sports sector and some critical environmental factors that influence the competitiveness and entrepreneurship in Colombia to start a new business. The results show in an orderly way all information aggregated, which can help potential investors and entrepreneurs to make a decision based on their preferences. Finally, the applicability of this method in real case can be given in aggregation different sources of information to help at dealing decision-making processes.
Topical Treatment of Herpes Simplex virus Infection with Enzymatically Created siRNA Swarm
Authors: Paavilainen Henrik , Lehtinen Jenni , Romanovskaya Alesia , Nygårdas Michaela , Bamford Dennis H , Poranen Minna M , Hukkanen Veijo
Published: March 2017

Background

Herpes simplex virus (HSV) is a common human pathogen. Despite current antivirals, it causes a significant medical burden. Drug resistant strains exist and they are especially prevalent in immunocompromised patients and in HSV eye infections. New treatment modalities are needed.

Methods

BALB/c mice were corneally infected with HSV and subsequently treated with a swarm of enzymatically created, Dicer-substrate small interfering RNA (siRNA) molecules that targeted the HSV gene UL29. Two infection models were used, one in which the infection was predominantly peripheral and another in which it spread to the central nervous system. Mouse survival, as well as viral spread, load, latency and peripheral shedding, was studied.

Results

The anti-HSV-UL29 siRNA swarm alleviated HSV infection symptoms, inhibited viral shedding and replication and had a favourable effect on mouse survival.

Conclusions

Treatment with anti-HSV-UL29 siRNA swarm reduced symptoms and viral spread in HSV infection of mice and also inhibited local viral replication in mouse corneas.
Long-Acting Reversible Contraception: A Primer for the Primary Care Pediatrician
Authors: Fernandez Sabrina
Published: March 2017

Long-acting reversible contraception (LARC) is the most effective method of preventing pregnancy in young women and adolescents. The two types of LARC methods are the intrauterine device and the implantable rod device. The success of these methods is demonstrable due to the “perfect use” and “typical use” failure rates being near identical. Pediatricians must be comfortable counseling patients, including adolescents, about LARC methods and how to access them. This primer provides some background about the types of LARC methods, details about their efficacy and side effects, and the role of the primary pediatrician.

[
Pediatr Ann
. 2017;46(3):e79–e82.]
Shear Bond Strength and ARI Score of Chemically Cured Orthodontic Adhesive Resins
Authors: Nidhiritdhikrai Pacharapilai , Anuwongnukroh Niwat , Dechkunakorn Surachai , Wichai Wassana
Published: March 2017

The purpose of this study was to compare shear bond strength and to evaluate Adhesive Remnant Index (ARI) score among three chemically cured orthodontic adhesive resins, namely Unite (3M Unitek, USA), Rely-a-Bond (Reliance, USA) and Ortho-Force (China). Materials and methods: Ninety extracted human maxillary premolars were randomly divided into 3 groups (30 teeth/group). Upper premolar metal brackets (Ormco, USA) were boned by using the following adhesive systems: Unite, Rely-a-Bond and Ortho-Force. After 24 hours, shear bond strength was tested by using a Universal Testing Machine with a crosshead speed of 0.5 mm/min. After debonding, all teeth and brackets were examined under 10-times magnification and scored by using Image-Pro Plus 7.0 software program. Results: One-way ANOVA followed by post-hoc Tukey HSD multiple comparison test showed a statistically significant (P<0.05) difference among groups. Ortho-Force had the lowest shear bond strength (17.53±3.60 MPa) and demonstrated statistically significant difference (P<0.05) from the other groups. The difference between Unite (22.40±3.11 MPa) and Rely-a-Bond (20.67±2.70 MPa) was not statistically significant. The bond failure sites were categorized according to the ARI, and the Chi-square test showed significant differences in the ARI scores (P<0.05) among all sample groups. The ARI score of 3 was found to be the most prevalent in Ortho-force (73.33%), followed by Unite (66.67%), and Rely-a-Bond (0%). In Rely-a-Bond group, ARI score of 1 was the most prevalent (66.67%). Only Unite had no residual adhesive left on tooth surface after debonding (6.67%). Conclusions: Unite and Rely-a-Bond produced greater shear bond strength than Ortho-Force. According to ARI score, Unite and Ortho-Force had a high frequency of all the adhesive remained on the tooth surface but Rely-a-Bond had high frequency of less than half the adhesive remained on the tooth surface.
Mechanical and Physical Properties of Various Types of Dental Floss
Authors: Supanitayanon Lalita , Dechkunakorn Surachai , Anuwongnukroh Niwat , Srikhirin Toemsak , Roongrujimek Pitchaya , Tua-Ngam Peerapong
Published: March 2017

To compare maximum load, percentage of elongation, physical characteristics of 4 types of dental floss: (1) Thai Silk Floss (silk, waxed), (2) Oral B® Essential Floss (nylon, waxed), (3) Experimental Floss Xu (nylon, unwaxed), (4) Experimental Floss Xw (nylon, waxed). Four types of floss were tested (n=30) with a Universal Testing Machine (Instron®). Each sample (30 cm long, 5 cm segment) was fixed, and pulled apart with load cell of 100 N and a test speed of 100 mm/min. Physical characteristics were investigated by digital microscope under 2.5×10 magnification, and scanning electron microscope under 1×100 and 5×100 magnification. The size of the filaments was measured in micron (μm) and the fineness was measured in Denier. For mechanical properties, the maximum load and the percentage of elongation were presented as mean ± SD. The distribution of the data was calculated by the Kolmogorov-Smirnov test. One-way ANOVA and multiple comparison (Tukey HSD) were used to analyze the differences among the groups with the level of a statistical difference at p < 0.05. The maximum load of Floss Xu, Floss Xw, Oral B and Thai Silk were 47.39, 46.46, 25.38, and 23.70 N, respectively. The percentage of elongation of Oral B, Floss Xw, Floss Xu and Thai Silk were 72.43, 44.62, 31.25, and 16.44%, respectively. All 4 types of dental floss showed statistically differences in both the maximum load and percentage of elongation at p < 0.05, except for maximum load between Floss Xw and Floss Xu that showed no statistically significant difference. Physical characteristics of Thai silk revealed the most disintegrated, the smallest, and the least fine filaments. Floss Xu had the highest maximum load. Oral B had the highest percentage of elongation. Wax coating on Floss X increased the elongation but had no significant effect on the maximum load. The physical characteristics of Thai Silk resulted in the lowest mechanical properties values.
Microwave-Assisted Synthesis of Unmodified Gold Nanoparticles for Colorimetric Detection of Dopamine
Authors: Detsri Ekarat , Kamhom Kanrayasiri , Detsri Chatsuda
Published: March 2017

Unmodified gold nanoparticles (AuNPs) have been successfully synthesized by the chemical reduction of tetrachloride gold (III) ions ([AuCl4]-) in the presence of sodium citrate based on the rapid microwave−assisted approach. The diameter of the synthesized nanoparticles was found in the range of 16.50±2.75 nm. The AuNPs were characterized using UV−vis spectrophotometer, zeta potential analyzer and transmission electron microscope (TEM). The sodium citrate protected AuNPs were found to be selective and sensitive for the detection of dopamine. It was based on the aggregation change of the nanoparticles from random coil to hairpin structure upon the addition of dopamine concentration. The red shift of the plasmonic peak wavelength of AuNPs could be used for the detection of dopamine. The response to dopamine allows for a linear range from 10 to 125 mg⋅L-1 (R2 = 0.9804) with a limit of detection (LOD) at a signal to noise ratio of 3 of 12.85±1.38 mg⋅L-1. The colorimetric sensor was evaluated with 98.0−99.9% recovery of added dopamine in urine sample. The proposed sensor was successfully applied to the determination of dopamine in biological samples.
Study on Mn-Fe-LDH Material for Remediation of Arsenic Contaminated Water
Authors: Wang Wei Zhuo , Bian Jian Min
Published: March 2017

Arsenical water pollution refers to the toxicity of arsenic. The form of trivalent arsenic has been seen as more toxic substances, which will be great improved by the manmade pollution. Compared with other technologies, adsorption is the main method of removal of arsenic pollution, for its higher efficiency and lower cost. Based on the adsorption theory and ion exchange method, the layered double hydroxides material containing ferric iron and manganese (Mn-Fe-LDH) was prepared to remove arsenic in this paper. We have designed some experiments for synthesis of this material. The reaction process and elemental compositions has been studied and the adsorption property of arsenic adsorption onto layered double hydroxides was verified through a series of experiments. Study shows that the Mn-Fe-LDH material can be used as a good adsorbent material for its high removal efficiency. The adsorption capacity of the Mn-Fe-LDH material is not affected by the interference of pH and Cl-/SO42- ion strength. It was a broad prospect for the development and application of arsenic removal materials.
Research on the Measurement System of Friction Torque for Arc Structure Servo Mechanism
Authors: Wu Wei , Shang Jiang Zhong , Cao Yu Jun , Yu Nai Hui
Published: March 2017

In this paper, in order to realize friction torque measurement and assembly behavior analysis of arc structure servo mechanism (ASSM), a general measurement system applied, meanwhile structural characteristics and performance of the ASSM are analyzed. Based on the fundamental of electrical method, the system is built up by the principle of vertical structure in line. So the system can applied to all kinds of ASSM by replacing the U-shape frame which suits to the target servos. The experiment is carried out on a certain type, the mean value of dynamic friction torque is about 1.00Nm, and the variance of measured data is about 0.01. The results indicate that the measurement system can measure friction torque and its inhomogeneity effectively and can be used in measurement of friction torque on other ASSM.
Preparation of FePt Nanoparticles by Pulsed Plasma in Liquid Method
Authors: Tamura Shota , Kelgenbaeva Zhazgul , Yamamoto Kenta , Chen Li Liang , Mashimo Tsutomu
Published: March 2017

FePt alloys are an important class of materials in permanent magnetic applications because of their large uniaxial magnetocrystalline anisotropy and good chemical stability. We have applied the pulsed plasma in liquid method to synthesis nanoparticles. Short duration of pulse and quenching effects of the surrounding liquid limit the size of crystal. That enable synthesis of small size and metastable nanoparticles. In this study, ferromagnetic FePt nanoparticles were successfully synthesized. Face-centered-cubic (FCC) A1-type phase was synthesized from FePt (Fe:PT=50:50, 55:45 in atomic %) alloy rod electrodes using the pulsed plasma in ethanol. The ordered face-centered-tetragonal (FCT) L10-type phase FePt was obtained by annealing the A1-type phase at 400oC for 1 h. The average diameter of L10-type FePt nanoparticles was less than 10 nm. Vibrating Sample Magnetometer (VSM) analysis showed that the coercivity of L10-type nanoparticles was much larger than that of the A1-type phase nanoparticles.
Investigation of Chip Dimensional Characteristics Created by the Specific Cutting Tool at the Machining of 12 050 Steel
Authors: Monkova Katarina , Monka Peter , Hric Slavomir , Ondek Vladimir , Urban Marek
Published: March 2017

The article deals with the investigation of chip dimensional characteristics that are created by the tool with linear cutting edge nonparallel to the workpiece axis. It is the tool with special geometry that was designed by authors in order to improve product quality and shorten the time of its production. Aim of the research has been focused on the obtaining of dependencies of the chip dimensions on both feed per revolution and setting of tool corner height in relation to the workpiece axis during machining of 12 050 steel. Measured data were processed statistically and they were evaluated by means of regression analysis in matrix expression. Measured data have indicated that with the increasing of feed per revolution, the chip width and chip thickness are increasing, too. As for the depth of cut, if it is increasing, the width of chip is also increasing, but chip thickness is not changing. The experiments have shown that the shape of chips at the machining by tool with linear cutting edge is not suitable for usage in production without direct control by operator. Therefore, when considering usage of this tool, it will be necessary to design the tool with chip breaker.
Improvement of Water Vapor Permeability of LLDPE/EVA Film with Zeolite A as Filler
Authors: Rukchonlatee Suparat , Jaisomboon Nattarika , Sooknoi Tawan
Published: March 2017

In this work, water vapor permeability of linear low density polyethylene (LLDPE)/ethylene vinyl acetate copolymer (EVA) film is improved by incorporation of zeolite A as filler (0-25%wt) for prolonging shelf-life of fresh produces. All films were characterized by SEM, DSC, tensile testing, contact angle measurement and tested for water vapor permeability (WVP). The shelf-life of Bird’s eye chili in the film samples was also tested at 10°C for 21 days. It was found that zeolite A particles were virtually dispersed in EVA phase. Accordingly, crystallinity and tensile properties of LLDPE/EVA/Zeolite A films is independent to zeolite loading. Despite, when zeolite loading was increased, the dispersion became low. The film’s wetting behavior was enhanced by increasing zeolite content in the LLDPE/EVA/Zeolite A films. The observed increase in the film’s polarity significantly enhances the WVP. Therefore, less water condensed can be found inside the package made with LL80E20Ze25 film, as compared to LLDPE or LLDPE/EVA film. The LL80E20Ze25 also possesses comparable tensile properties to the commercial LLDPE film and hence can used as packaging for extending the shelf-life of fresh produces.
Study on the Development of Demagnetizing System for Hub Bearing Inner of Automobile
Authors: You Seung Hyeon , Oh Sung Hoon
Published: March 2017

Demagnetizer has been used in the field of non-destructive test or processing as a tool for removing residual magnetic created on the surface of processed object. In case of residual magnetic left on the part, metal particles around them adhere with each other causing the destruction or abrasion on the part. This study is to develop automatic demagnetizing system for improving the quality of processed items by designing the residual magnetic measuring system, demagnetizing system, and total system to detect magnetic that is derived on parts in the middle of processing in application to bearing process. For this, control system, measuring system, and HMI program that managed them were developed making it feasible to expect the application of them on various automatic processing.
Low Temperature Synthesis of the Carbon Micro Materials
Authors: An Si Eun , Kim Sung Hoon
Published: March 2017

The formation of the carbon microcoils could be achieved under the low temperature (550°C). Ni powders were used as the catalyst on the alumina substrate. C2H2 was used as a source gas and a few amount of SF6 gas were used as an additive gas under the thermal chemical vapor deposition system. The surface morphologies of as-grown carbon materials at the low temperature (550°C) were also investigated according to the total pressure and the injection time of SF6 flow. At 80Torr and 10min injection time of SF6 flow, the carbon microcoils were highly developed on the entire surface of the sample. The lower or higher total pressure and the longer injection time of SF6 flow deteriorated the formation of CMCs. The head area of the carbon microcoils was closely investigated and the growth mode for the initiation of the carbon microcoils at the low temperature was suggested.
Effect of Mechanical Activation on the Structural Parameters of Ceramic Powders cBN-Co, hBN-Co
Authors: Rusinov Peter Olegovich , Blednova Zhesfina
Published: March 2017

The paper describes the study of mechanical activation of multi-component ceramic powder materials based on boron nitride. The mechanical activation of the powders was carried out according to the best optimal parameters in a ball mill AGO-2U. Increasing the time of mechanical activation leads to more fine-grained powders. We described the technique of mechanical activation of ceramic powder materials. We introduced the results of X-ray diffraction analysis of the ceramic powder cBN, cBN-Co, hBN-Co before and after mechanical activation. We generated mathematical equations of dependence of an average powder particle size on the average mechanical activation time. We described how the crystal lattice "a" parameters and unit cell volume "V" of cBN and hBN powders depend on mechanical activation time. We studied the chemical composition of powder materials. We also studied the structural parameters of ceramic powders.
Research on Material Fatigue Test of Steel Fiber Reinforced Concrete under Tension and Compression Loading
Authors: Guo Meng Meng , Feng Zhong Ren , Chen Yang
Published: March 2017

Using the material testing machine of electro-hydraulic servo fatigue tests had been carried out on ordinary concrete and steel fiber reinforced concrete. The fatigue life, strength, stress and strain had been measured under tension and compression loading. The variation of fatigue was analyzed based on the test results. Having regression analysis, obtained the fatigue strength. Mean-while, the fatigue strain-life curves of ordinary concrete and steel fiber reinforced concrete had been made after data processing. The results had been showed that the fatigue property of steel fiber reinforced concrete was significantly higher than that of ordinary concrete. And the fatigue strength increased about 32.6% compared with ordinary concrete. The tensile and compressive fatigue strain were slightly smaller than that of ordinary concrete.
Modeling of Building Materials as Complex Systems
Authors: Garkina Irina , Danilov Alexander , Skachkov Yuri Petrovich
Published: March 2017

We considered the problems of mathematical modeling of composite materials in the example of the development of materials for the protection against ionizing radiation. Construction materials are provided as a complex system with the appropriate attributes. The structure and physico-mechanical properties of the material were determined by the results of the modeling of kinetic processes. Process of forming properties is described by the differential equation in deviations from the equilibrium state (as for dispersion system). It is taken into account the elastic and damping properties of the material. To predict the behavior of the building material and the formation of his private mathematical models are used a representation of the processes as of time series. It is given the algorithm for studies (with considering prehistory) of formation of the basic physical and mechanical properties of epoxy composites for radiation protection. We present an example of the identification of building materials with special properties. Approaches used effectively in the development of materials with special properties.
A Study on CO2 Emissions in End-of-Life Phase of Residential Buildings in Korea: Demolition, Transportation and Disposal of Building Materials
Authors: Cha Gi Wook , Hong Won Hwa , Kim Jin Ho
Published: March 2017

Architecture and building industry have been made diversified efforts to create a construction environment that promotes resource recycling. Many studies have been done to better understand and reduce energy consumption and CO2 emissions throughout a building’s lifecycle. However, to promote sustainable development and a construction environment that facilitates resource recycling, more understanding and research is needed on energy consumption and CO2 emissions during the stage of dismantling a building. Noting that, this research investigates CO2 emissions in a building’s End-Of-Life (EOL) phase that includes dismantling of a building, transport and disposal of the waste generated in the course of dismantling residential buildings in Korea. According to the results of this study, CO2 emissions in a building’s EOL phase was 3,561kg CO2/100m2 for apartments, 3,184 kgCO2/100m2 for brick houses and 1,137 kg CO2/100m2 for wooden houses. The results showed that transport and disposal process of demolition waste accounts for 90% of all CO2 emissions in a building’s EOL phase. From this finding, it is necessary to have a proper, effective strategy for transport and disposal of demolition waste from dismantled buildings’ in order to reduce CO2 emissions during a building’s EOL phase.
Comparative Study of Sound Absorption Coefficients of Coir/Kenaf/Sugarcane Bagasse Fiber Reinforced Epoxy Composites
Authors: Jayamani Elammaran , Soon Kok Heng , bin Bakri Muhammad Khusairy , Hamdan Sinin
Published: March 2017

This research focuses on the sound absorption coefficient of three different natural fibers reinforced epoxy composites. The natural fibers used are coconut coir, kenaf, and sugarcane bagasse. All of these fibers were mixed with epoxy resin and hardener with a ratio of 4:1. The mixtures were then poured into a circular mold and compressed by using compression molding technique. It was left for curing for 24 hours at standard room temperature. The results were obtained using the two-microphone transfer functions impedance tube method according to ASTM E1050-12. It is found that as the fiber loading increased, the sound absorption coefficient of the composites increased. 20wt% Coconut coir epoxy composites and 20wt% kenaf fiber epoxy composites have the highest sound absorption coefficient with almost similar sound absorption of 0.078 at 5000Hz. While, 20wt% sugarcane bagasse epoxy composites have sound absorption of 0.075 at 5000Hz.