bluuebunny/crossref_metadata_2025 huggingface dataset:
Ephemeris Errors and the Gravitational-wave Signal: Harmonic Mode Coupling in Pulsar Timing Array Searches
Authors: Roebber Elinore
Published: May 2019

Any unambiguous detection of a stochastic gravitational wave background (GWB) by a pulsar timing array will rest on the measurement of a characteristic angular correlation between pulsars. The ability to measure this correlation will depend on the geometry of the array. However, spatially correlated sources of noise, such as errors in the planetary ephemeris or clock errors, can produce false-positive correlations. The severity of this contamination will also depend on the geometry of the array. This paper quantifies these geometric effects with a spherical harmonic analysis of the pulsar timing residuals. At least nine well-spaced pulsars are needed to simultaneously measure a GWB and separate it from ephemeris and clock errors. Uniform distributions of pulsars can eliminate the contamination for arrays with large numbers of pulsars, but pulsars following the galactic distribution of known millisecond pulsars will always be affected. We quantitatively demonstrate the need for arrays to include many pulsars and for the pulsars to be distributed as uniformly as possible. Finally, we suggest a technique to cleanly separate the effect of ephemeris and clock errors from the gravitational wave signal.
Possible Cool Prominence Materials Detected within Interplanetary Small Magnetic Flux Ropes
Authors: Wang J. M. , Feng H. Q. , Li H. B. , Zhao A. K. , Tian Z. J. , Zhao G. Q. , Zhao Y. , Liu Q.
Published: May 2019

Previous studies indicate that interplanetary small magnetic flux ropes (SMFRs) are manifestations of microflare-associated small coronal mass ejections (CMEs), and the hot material with high-charge states heated by related microflares are found in SMFRs. Ordinary CMEs are frequently associated with prominence eruptions, and cool prominence materials are found within some magnetic clouds (MCs). Therefore, the predicted small CMEs may also be frequently associated with small prominence eruptions. In this work, we aim to search for cool prominence materials within SMFRs. We examined all the O5+ and Fe6+ fraction data obtained by the Advanced Composition Explorer (ACE) spacecraft during 1998–2008 and found that 13 SMFRs might exhibit low-charge-state signatures of unusual O5+ and/or Fe6+ abundances. One of the 13 SMFRs also exhibited signatures of high ionic charge states. We also reported a SMFR with high Fe6+ fraction, but the values of Fe6+ is a little lower than the threshold defining unusual Fe6+. However, the Solar Dynamics Observatory/ Atmospheric Imaging Assembly observations confirmed that the progenitor CME of this SMFR is associated with a small eruptive prominence, and the observations also supported the prominence materials were embedded in the CME. These observations are at the edge of the capabilities of ACE/Solar Wind Ion Composition Spectrometer and it cannot be ruled out that they are solely caused by instrumental effects. If these observations are real, they provide new evidence for the conjecture that SMFRs are small-scale MCs but also imply that the connected small CMEs could be associated with flares and prominence eruptions.
Exploring the Mass Segregation Effect of X-Ray Sources in Globular Clusters: The Case of 47 Tucanae
Authors: Cheng Zhongqun , Li Zhiyuan , Li Xiangdong , Xu Xiaojie , Fang Taotao
Published: May 2019

Using archival Chandra observations with a total exposure of 510 ks, we present an updated catalog of point sources for globular cluster (GC) 47 Tucanae. Our study covers an area of ∼176.′7 2 (i.e., with R ≲ 7.′5) with 537 X-ray sources. We show that the surface density distribution of X-ray sources in 47 Tuc is highly peaked in the cluster center, rapidly decreases at intermediate radii, and finally rises again at larger radii, with two distribution dips at R ∼ 100″ and R ∼ 170″ for the faint (L
X ≲ 5.0 × 1030 erg s−1) and bright (L
X ≳ 5.0 × 1030 erg s−1) groups of X-ray sources, respectively. These distribution features are similar to those of blue straggler stars (BSSs), where the distribution dip is located at R ∼ 200″. By fitting the radial distribution of each group of sources with a “generalized King model,” we estimated an average mass of 1.51 ± 0.17 M
⊙, 1.44 ± 0.15 M
⊙ and 1.16 ± 0.06 M
⊙ for the BSSs, bright X-ray sources, and faint X-ray sources, respectively. These results are consistent with the mass segregation effect of heavy objects in GCs, where more massive objects drop to the cluster center faster and their distribution dip propagates outward further. Besides, the peculiar distribution profiles of X-ray sources and BSSs are also consistent with the mass segregation model of binaries in GCs, which suggests that, in addition to the dynamical formation channel, primordial binaries are also a significant contributor to the X-ray source population in GCs.
Magnetohydrodynamic Particle-in-cell Simulations of the Cosmic-Ray Streaming Instability: Linear Growth and Quasi-linear Evolution
Authors: Bai Xue-Ning , Ostriker Eve C. , Plotnikov Illya , Stone James M.
Published: May 2019

The gyro-resonant cosmic-ray (CR) streaming instability is believed to play a crucial role in CR transport, leading to the growth of Alfvén waves at small scales that scatter CRs, and impacts the interaction of CRs with the interstellar medium (ISM) on large scales. However, extreme scale separation (λ ≪ pc), low CR number density (n
CR/n
ISM ∼ 10−9), and weak CR anisotropy (∼v
A/c) pose strong challenges for proper numerical studies of this instability on a microphysical level. Employing the recently developed magnetohydrodynamic particle-in-cell method, which has unique advantages to alleviate these issues, we conduct 1D simulations that quantitatively demonstrate the growth and saturation of the instability in the parameter regime consistent with realistic CR streaming in the large-scale ISM. Our implementation of the δf method dramatically reduces Poisson noise and enables us to accurately capture wave growth over a broad spectrum equally shared between left- and right-handed Alfvén modes. We are also able to accurately follow the quasi-linear diffusion of CRs subsequent to wave growth, which is achieved by employing phase randomization across periodic boundaries. Full isotropization of the CRs in the wave frame requires the pitch angles of most CRs to efficiently cross 90° and can be captured in simulations with relatively high wave amplitude and/or spatial resolution. We attribute this crossing to nonlinear wave–particle interaction (rather than mirror reflection) by investigating individual CR trajectories. We anticipate that our methodology will open up opportunities for future investigations that incorporate additional physics.
Resolving the Decades-long Transient FIRST J141918.9+394036: An Orphan Long Gamma-Ray Burst or a Young Magnetar Nebula?
Authors: Marcote B. , Nimmo K. , Salafia O. S. , Paragi Z. , Hessels J. W. T. , Petroff E. , Karuppusamy R.
Published: May 2019

Ofek identified FIRST J141918.9+394036 (hereafter FIRST J1419+3940) as a radio source sharing similar properties and host galaxy type to the compact, persistent radio source associated with the first known repeating fast radio burst, FRB 121102. Law et al. showed that FIRST J1419+3940 is a transient source decaying in brightness over the last few decades. One possible interpretation is that FIRST J1419+3940 is a nearby analog to FRB 121102 and that the radio emission represents a young magnetar nebula (as several scenarios assume for FRB 121102). Another interpretation is that FIRST J1419+3940 is the afterglow of an “orphan” long gamma-ray burst (GRB). The environment is similar to where most such events are produced. To distinguish between these hypotheses, we conducted very long baseline interferometric (VLBI) radio observations using the European VLBI Network (EVN) at 1.6 GHz to spatially resolve the emission and to search for millisecond-duration radio bursts. We detect FIRST J1419+3940 as a compact radio source with a flux density of 620 ± 20 μJy (on 2018 September 18) and a source size of 3.9 ± 0.7 mas (i.e., 1.6 ± 0.3 pc given the angular diameter distance of 83 Mpc). These results confirm that the radio emission is nonthermal and imply an average expansion velocity of (0.10 ± 0.02)c. Contemporaneous high-time-resolution observations using the 100 m Effelsberg telescope detected no millisecond-duration bursts of astrophysical origin. The source properties and lack of short-duration bursts are consistent with a GRB jet expansion, whereas they disfavor a magnetar birth nebula.
Plant diversity changes in a nature reserve: a probabilistic sampling method for quantitative assessments
Authors: Chelli Stefano , Simonetti Enrico , Campetella Giandiego , Chiarucci Alessandro , Cervellini Marco , Tardella Federico Maria , Tomasella Michela , Canullo Roberto
Published: May 2019

Species pool conservation is critical for the stability of ecosystem processes. However, climate and land use changes will likely affect biodiversity, and managers of protected areas are under increasing pressure to monitor native species diversity changes by approaches that are scientifically sound and comparable over time. Here we describe a plant diversity monitoring system in use since 2002 in the “Montagna di Torricchio” Nature Reserve (LTER_EU_IT_033), a Central Apennines representative area of 317 ha, most of which is under strict protection. The aim of this paper was to assess changes in plant species richness over time and to deduce the patterns of species assemblage. The monitoring system was based on a probabilistic sampling design representative of the different physiognomic vegetation types occurring in the Reserve. A total of 34 plots (10×10m) were sampled in 2002, 2003 and 2015, and their species presence/absence and relative coverage were estimated. Repeated measure ANOVA was used to test for plot-level and ecosystem-based changes in species richness along the study period. Temporal nestedness and temporal turnover metrics were used to assess patterns of species’ compositional changes. The results showed significantly different levels of species richness depending on the year, with the lowest value in 2003, probably linked to extreme drought events. Forest systems were comparatively stable, demonstrating the capacity to buffer interannual climate variability. Regarding compositional changes along the entire period (2002–2015), we found random patterns of both temporal nestedness and turnover, indicating stability in species composition. However, we also showed the contemporary occurrence of species loss and species replacement processes, considering the dry year 2003, a finding which should be further explored through fine-scale studies to unravel mechanisms of community assembly under drought. The use of a probabilistic sampling design representative of the different physiognomic vegetation types proved to be advantageous in monitoring the Nature Reserve vegetation and collecting reliable quantitative information. This data, in turn, provides the basis for improvements in management practices and proposed adaptation measures.
Successions of phytobenthos species in a Mediterranean transitional water system: the importance of long term observations
Authors: Petrocelli Antonella , Cecere Ester , Rubino Fernando
Published: May 2019

The availability of quantitative long term datasets on the phytobenthic assemblages of the Mar Piccolo of Taranto (southern Italy, Mediterranean Sea), a lagoon like semi-enclosed coastal basin included in the Italian LTER network, enabled careful analysis of changes occurring in the structure of the community over about thirty years. The total number of taxa differed over the years. Thirteen non-indigenous species in total were found, their number varied over the years, reaching its highest value in 2017. The dominant taxa differed over the years. The number of species in each taxonomic division also varied. In addition to the centuries-old exploitation of its biotic resources, mainly molluscs, the basin has been subject for a long time to a range of anthropogenic driving forces linked to urbanisation, shipbuilding, agriculture and military activities, which have caused chemical and biological pollution, eutrophication and habitat destruction. It may therefore be assumed that these changes were closely related to human activities. Indeed, it was observed that the reduction of only one of these forces, i.e. urban sewage discharge, triggered the recovery of phytobenthos. Therefore, it may be assumed that if the anthropogenic pressure on the Mar Piccolo was eased, it could once again become the paradisiacal place it was held to be in ancient times.
Multiannual decrement of nutrient concentrations and phytoplankton cell size in a Mediterranean reservoir
Authors: Pulina Silvia , Lugliè Antonella , Mariani Maria Antonietta , Sarria Marco , Sechi Nicola , Padedda Bachisio Mario
Published: May 2019

Reservoirs are primary water resources for many uses in the Mediterreanean region and need dedicated studies for understanding the complexity of their dynamics particularly vulnerable to local and global stressors. This study focused on phytoplankton variations in relation to seasonal environmental changes on a multiannual time scale (2006–2015) at a Mediterranean eutrophic reservoir (Bidighinzu Lake, Italy) belonging to the Italian, European and International Long Term Ecological Research networks. Phytoplankton cell density, volume and biomass and chlorophyllaconcentrations were analysed together with meteo-climatic, hydrological, physical and chemical variables to detect trends and correlations. The period under study was also compared with previous years to assess the presence of significant differences in the environmental and planktonic compartments. Multiannual changes were more pronounced in summer than in the other seasons during the decade under study. The most conspicuous environmental changes were a significant decrease in summer nutrient concentrations in the reservoir and a simultaneous anthropic pressure reduction in the watershed. In addition, the mixing zone and euphotic zone ratio also increased. Multiannual changes in summer phytoplankton composition consisted of an increased density of smaller Bacillariophyceae and Cyanophyceae, which replaced larger species of the same phytoplankton classes. This resulted in opposite trends of total phytoplankton cell density (increasing) and mean phytoplankton cell volume (decreasing) over the study years. The nutrient decrement was statistically the strongest environmental driver of the phytoplankton changes observed in the reservoir. However, the mixing zone and the euphotic zone ratio and water temperature also significantly affected the multiannual phytoplankton variations. Therefore, we conclude that the success of small cell-sized phytoplankton in Bidighinzu Lake was most probably due to the synergic interactions of more environmental forces related to changing anthropic pressures and climate variability. Our results highlight the importance of long-term monitoring of reservoirs in the Mediterranean basin, especially in semi-arid regions where the need and scarcity of high quality water will be further exacerbated due to the global climate change.
Time series and beyond: multifaceted plankton research at a marine Mediterranean LTER site
Authors: Zingone Adriana , D'Alelio Domenico , Mazzocchi Maria Grazia , Montresor Marina , Sarno Diana , team LTER-MC
Published: May 2019

Plankton are a pivotal component of the diversity and functioning of coastal marine ecosystems. A long time-series of observations is the best tool to trace their patterns and variability over multiple scales, ultimately providing a sound foundation for assessing, modelling and predicting the effects of anthropogenic and natural environmental changes on pelagic communities. At the same time, a long time-series constitutes a formidable asset for different kinds of research on specific questions that emerge from the observations, whereby the results of these complementary studies provide precious interpretative tools that augment the informative value of the data collected. In this paper, we review more than 140 studies that have been developed around a Mediterranean plankton time series gathered in the Gulf of Naples at the station LTER-MC since 1984. These studies have addressed different topics concerning marine plankton, which have included: i) seasonal patterns and trends; ii) taxonomic diversity, with a focus on key or harmful algal species and the discovery of many new taxa; iii) molecular diversity of selected species, groups of species or the whole planktonic community; iv) life cycles of several phyto- and zooplankton species; and v) interactions among species through trophic relationships, parasites and viruses. Overall, the products of this research demonstrate the great value of time series besides the record of fluctuations and trends, and highlight their primary role in the development of the scientific knowledge of plankton much beyond the local scale.
Ambivalence du calculable et crise du jugement
Authors: Lassègue Jean
Published: May 2019

L’article traite de l’informatisation du droit qui met en crise l’exercice du jugement en le privant d’une partie de ses prérogatives fondamentales. Il explore le rapport entre deux sortes de légitimité, juridique et numérique, en s’appuyant sur des arguments tirés de l’histoire des sciences : l’argument du Dominateur de Diodore Cronos, la métaphysique alphabétique de Leibniz et le théorème de limitation du calculable de Turing.
Fichte et le mal radical kantien
Authors: Dumont Augustin
Published: May 2019

L’objectif de cet article est d’interroger la manière dont Fichte se réapproprie la problématique kantienne du mal radical. Il est aujourd’hui convenu de voir en Schelling le véritable successeur de Kant en la matière, en dépit de l’écart existant entre sa perspective ontologique et le point de vue critique. Nous tentons de montrer que, loin de faire retour vers le « philanthropisme » des Lumières à cet égard, Fichte prend le mal radical très au sérieux. L’article propose une lecture attentive du § 16 de la Sittenlehre. Il démontre que notre capacité à faire le mal trouve sa source dans la substitution de la volonté propre du sujet à la loi de l’autonomie. Une telle substitution relève de la conviction du sujet et constitue assurément un acte libre.
Wittgenstein : de l’action à l’expression
Authors: Steiner Pierre
Published: May 2019

Certaines thèses philosophiques récentes en sciences cognitives, dont l’énactivisme, échappent aux critiques qui ont longtemps été adressées aux sciences cognitives à partir d’une certaine lecture de Wittgenstein. Pour autant, un réexamen des remarques de Wittgenstein sur le mythe des processus mentaux et sur les circonstances d’usage des concepts psychologiques permet de dégager des présupposés communs à l’énactivisme et aux sciences cognitives classiques. On présente alors l’importance du concept d’expression, chez Wittgenstein, pour penser les relations entre vie de l’esprit et formes du comportement, en montrant que ce concept reste compatible avec une approche scientifique de la cognition.
« Langaginalité », une perspective pour la socialité langagière
Authors: Lee Chang-Hoon
Published: May 2019

Certains phénomènes langagiers, atypiques et dynamiques, observables dans diverses sphères de la vie quotidienne, du SMS au papotage, n’arrivent pas à s’expliquer selon les catégories en vigueur. C’est surtout leur forme, extravagante, plutôt que leur sens qui est porteuse de toutes sortes d’enjeux sociaux. Pour pouvoir envisager un sens sociologique à ces phénomènes, il s’impose de concevoir une nouvelle perspective épistémologique en sociologie du langage. Il s’agit donc d’un nouveau paradigme, le « langaginal », qui considère le langage par son côté sensible, matériel et esthétique. Le « langagier », en revanche, le paradigme dominant, se caractérise par la rationalité, la normativité et l’instrumentalité. Pour saisir intellectuellement cette « langaginalité », le premier chemin à prendre serait de voir les pratiques langagières telles qu’elles sont . Mais pour y parvenir, il faudra avant tout libérer le langage de la violence, violence faite sur le langage lui-même par la nature du rapport établi entre les mots et les choses au cours de l’histoire : rationalisme et fonctionnalisme.
Diffusion Induced Changes in Cast and Wrought M2 High-Speed Steel Subject to Homogenisation Annealing
Authors: Chaus Alexander S. , Sahul Martin , Bračík Matej
Published: May 2019

The influence of annealing at 1200 °C for 2, 4 and 8 h on the carbide microstructure of AISI M2 type high-speed steel obtained by both the foundry and conventional metallurgy technologies has been studied. The primary focus was on the kinetics of eutectic carbide decomposition and dissolution in both the cast and wrought M2 high-speed steels under the effect of high temperature.
Hydrogen Distribution in Partly Desorbed MgH2 Samples
Authors: Lushnikov Stepan Alexandrovich , Filippova Tatyana Victorovna , Bobrikov Ivan Anatolievich
Published: May 2019

The structure of MgH2 samples has been investigated by the neutron diffraction method at room temperature and 5 K. Samples of MgH2 have been prepared with vacuum extraction technique at high temperature. Obtained neutron data demonstrated that samples contain coexisting Mg and MgH2 phases in different rate. The distribution of hydrogen atoms in the structure of the samples is comparable at both temperatures. Collected neutron data and results of X-ray analysis show that microstructure of the samples is different at room and at low temperature. Non-stability of partly desorbed MgH2 samples after low temperature treatment has been discussed on basis of different diffusion of hydrogen atoms in varied microstructure.
PLA Composite Films Based on Acetate Substituted Microcrystalline Cellulose
Authors: Kale Bandu Madhukar , Rwahwire Samson , Kale Nilkanth Kisan , Musinguzi Wilson Babu
Published: May 2019

In recent years the utilization of natural fibers as reinforcing agents in thermoplastic composites has captured major attention. This research studied the effect of reaction time on the morphology, particle size, and melting point of microcrystalline cellulose and the reinforcement ability via mechanical characterization of the modified MCC in a blend of predominantly PLA matrix. In order to accomplish this latter goal, the acetylated microcrystals were blended with polylactic acid (PLA) polymer at 5 wt% concentration. Furthermore, a new method to control the degree of substitution and particle shape, size and distribution of microcrystalline cellulose by controlling the acetylation time is presented. A series of samples were prepared by the acetylation of microcrystalline cellulose to varying levels of acetate substitution. Composites of the acetate substituted microcrystalline cellulose with polylactic acid (PLA) showed a substantial increase in the modulus of rigidity at an optimum concentration and level of acetate substitution. Spectroscopic, morphological together with thermal and mechanical property data are presented and discussed.
Synthesis of Diamine Containing Chalcone Structure by Nitroammoniation and Aldol Condensation
Authors: Huang Yan Kai , Mei Qi Lin , Huang Zhi Xiong , Qin Yan , Zhu Di
Published: May 2019

In this paper, the structure of the photosensitive diamines was designed and the method of synthesizing such diamines was investigated. The 1-(3-aminophenyl)-3-(4-aminophenyl)-2-propen-1-one analyzed by elemental analysis and infrared analysis was synthesized through two-step experiments with Aldol condensation and Nitroammoniation process. Through the experiment the optimum reaction conditions are raw material ratio of 1:1, anhydrous ethanol dosage of 60 ml, 10 % NaOH dosage of 10 ml and reaction temperature of 25°C for 4h. The yield was about 55.4 %.
Development of a Self-Adhesive Cellulosic Hydrogel Wound Dressing
Authors: Tumolva Terence , Aquino Sweet Hazel , Cabeguin Kryzsa Mae , Imperial John Frederick
Published: May 2019

In this study, a self-adhesive hydrogel wound dressing was developed by combining hydroxyethyl cellulose (HEC) hydrogel with a tannic acid-polyethylene glycol (TAPE) adhesive bioadhesive with gelatin. Test samples of the cellulosic wound dressing were prepared with three (3) different mixing ratios of the crosslinking solution, three (3) different adhesive formulation, and two different hydrogel/adhesive contact area (flat, ridged). Adhesion performances of these samples on porcine skin were evaluated by performing a T-peel test. Analysis of the HEC/TAPE-gelatin interface showed that the HEC cross-linking agent formulation, adhesive thickness, and presence of surface ridges showed significant three-way interaction effects, and these parameters were modeled using orthogonal polynomials and optimized via response surface methodology (RSM). The adhesion on the HEC-TAPE-gelatin interface was also investigated further using scanning electron microscopy (SEM), where it had been observed that greater adhesion occurred with a decrease in cross-linking density, thinner adhesive layer, and the presence of ridges. Lastly, disk diffusion testing indicated greater antimicrobial activity (mean inhibition zone = 12 mm) against S. aureus and P. aeruginosa in contrast to commercial hydrogel dressings (mean inhibition zone = 7.5 mm), while MTT assay on human lymphocytes resulted to a 98% cell survival rate. Based on these results, it was concluded that it is feasible to use HEC hydrogel with TAPE-gelatin adhesive for manufacturing self-adhesive wound dressing products.
Carbon Dioxide Adsorbent Preparation by Coating Amine-Functionalized Pectin onto Zeolites
Authors: Jovellana John Andrew Kane P. , Pajarito Bryan B.
Published: May 2019

Increasing carbon dioxide (CO2) levels in the atmosphere caused by excessive greenhouse gas emissions is strongly associated to global warming and climate change. This study aims to prove the feasibility of using pectin as the backbone for amine functionalization with application as coating on zeolites for carbon dioxide capture. Characterization of the solutions using FTIR and of the adsorbents using SEM demonstrated the successful modification of pectin using NH3 and TETA as alternative amine-functionalized coating for adsorbent. It has been reported for the first time that the polysaccharide pectin can be aminated and modified for CO2 capture upon coated on substrates such as zeolites. The adsorption capacities at 5% breakthrough of the adsorbents coated with the modified pectin are 2.24 mmol/CO2 g adsorbent and 2.28 mmol/CO2 g adsorbent, when coated with NH3-modified and TETA-modified pectin, respectively. It is recommended for further study to synthesize substrates with higher surface area, and optimize the formulations of the pectin modification.
A Study on Heat Transfer Suppression Characteristics of Ferrofluid with Various Magnetic Field Intensities
Authors: Seo Jae Hyeong , Kim Namwon , Lee Moo Yeon
Published: May 2019

The objective of this study is numerically to investigate the heat transfer suppression characteristics of the ferrofluid with the various magnetic field intensities. In order to analyze the heat transfer suppression characteristics of the ferrofluid, the temperature characteristics and average Nusselt numbers of the ferrofluid were considered with variation of the magnetic field intensity. The magnetic field intensity ranged from 0 to 30000 A/m in order to analyze the effect of the magnetic field intensity on the insulation performance of the ferrofluid. The governing equations for mass, motion, momentum, energy, magnetization and Maxwell are used for the numerical analysis of the ferrofluid. The GSMAC method was used to solve the equations. The average temperatures of the ferrofluid at left cooled area were decreased with the increase of the magnetic field intensities. The average Nusselt numbers of the ferrofluid at the hot side with the magnetic field intensities of 10000 A/m, 20000 A/m and 30000 A/m were 43.7%, 61.4% and 63.8% lower than those at the magnetic field intensity of 0 A/m, respectively. The average Nusselt numbers of the ferrofluid at the cold side with the magnetic field intensities of 10000 A/m, 20000 A/m and 30000 A/m were 50.5%, 79.7% and 83.3% lower than those at the magnetic field intensity of 0 A/m, respectively. The heat transfer characteristics of the ferrofluid were suppressed under strong magnetic field intensity. As a result, the ferrofluid could be considered to improve the insulation performance of thermal storage tank.
Specific Energy Consumption Improvement with Applying Stainless Wire Mesh Porous Material for a Hot Air Dryer
Authors: Luampon Ratinun , Bunchan Sungwarn , Krittacom Bundit
Published: May 2019

This research was proposed to applying stainless wire mesh porous material for specific energy consumption improvement of a hot air dryer. In experimental consist two main parts, first part was a comparison of drying with and without hot air recirculation duct. Second part was a comparison of drying with and without stainless wire mesh porous material in drying chamber and hot air recirculation duct. Tilapia was drying product, stainless wire mesh in drying chamber was constant PPI=8 and 6 layers, stainless wire mesh in hot air recirculation duct was constant PPI=8 and varied layer at 6, 8 and 12 layers and hot air recirculation ratio 40%, 60% and 80%. Experimental result was, drying with hot air recirculation duct was higher drying rate than without recirculation duct and drying rate was increased, drying time was decreased and SEC was decreased with increased hot air recirculation ratio. At recirculation ratio 80%, SEC was lowest and decreased to 54.52% compared with without recirculation duct. Therefrom, the stainless wire mesh porous materials were inserted in the drying chamber and recirculation duct at PPI=8, 6 layers and PPI=8, 12 layers, respectively and used recirculation ratio 80%, it was found that SEC was lowest and decreased as about 62.21%.
Effect of Admixtures on the Thermo-Physical Properties of Non Autoclaved Light Weight Block Using Marble Dust
Authors: Sood Vivek , Negi S.K. , Suman B.M.
Published: May 2019

In the present study, use of marble dust an inert filler produced by the marble cutting industries in the development of light weight block (LWB) of density 800 kg/m3 by non-auto clave method has been studied. Various mechanical and thermo-physical properties have been evaluated. It has been possible to replace cement by up to 20% when no additive is used. With the use of activator and super plasticizer at 50% replacement of cement by marble dust, compressive strength and water absorption are well within the Indian standard code 2185. With the use of accelerator and super plasticizer it is possible to reduce the de moulding time from 48 hrs to 6 hrs. Thermal conductivity of blocks varies from 1.16 to 2.30 [W/mK]. The variation in thermal conductivity depends upon its density which varies from 800 kg/m3 to 2400 kg/m3.
Frictional and Mechanical Properties of Surface Modified Nickel-Titanium Orthodontic Archwires
Authors: Tantiwinyupong Natthalak , Chintavalakorn Rochaya , Santiwong Peerapong , Khantachawana Anak
Published: May 2019

The purpose of this study was to investigate the surface hardness, frictional force and load-deflection characteristic of three types of nickel-titanium archwires; DLC-coated, CH4-PBII and CF4-PBII NiTi orthodontic archwires. The NiTi wires were deposited with DLC films and were implanted with CH4 and CF4 using Plasma-Based Ion Implantation and Deposition (PBIID) method. These archwires and upper canine brackets with slot dimension of 0.022-inch were used in this study. Surface hardness of three types of surface modified NiTi orthodontic archwires was measured using atomic force microscopy (AFM). Frictional resistance was determined using a Universal Testing Machine with a load cell of 50 N. The custom-fabricated friction-testing device was designed and bonded each bracket in an accurate position. Load-deflection characteristic was evaluated by conducting the three-point bending test with universal testing machine. The results showed that DLC-coated NiTi wires had the lowest mean of frictional force followed by CH4-PBII, CF4-PBII and conventional NiTi wires. DLC-coated NiTi wires had the highest mean of surface hardness and there was no significant difference in the unloading force at 0.5, 1.0, 2.0 and 3.0 mm of the load-deflection graphs between different types of NiTi orthodontic archwires. The results can be concluded that the surfaces of nickel-titanium orthodontic archwires can be successfully modified by the PBIID method to increase surface hardness and reduce frictional force between stainless steel brackets and NiTi archwires. The load-deflection characteristics of three types of surface modified archwires remain unchanged.
Utilization of Brine Sludge in Controlled Low Strength Materials (CLSM)
Authors: Chen Shin Jen , Chen Chao Shi , Jhan Jyun Yong , Chen Ruei Fu
Published: May 2019

Controlled low-strength materials (CLSM) have begun to apply in a lot of countries because CLSM could distribute randomly in complex sites. Manufacturing from chlor-alkali industry, the brine sludge was used to replace the composition in CLSM for resource application. In this study, the mix composition of brine sludge replaced only the fine aggregates or all of the aggregates. Examining the suitable composition, the ball drop test and the compressive strength test were carried out. The ball drop test was applied to determine the readiness of the CLSM to accept loads prior, and the bearing capacity at different ages were measured by the compressive strength test. The results of the ball drop test in different replacements was 7 - 11.5 cm. The replacement of fine aggregates satisified the rule of CLSM. Replacing all of the aggregates, the mixtures were over 7.6 cm, which meant that the early strength at 1 day were not sufficient. The value of compressive strength at 28 days was 1.709 - 21.37 kgf/cm2, conforming the requirement of CLSM. Overall, the mixture which replaced the fine aggregates met all the specified values of CLSM. In particular, the composition of coarse aggregates reduce to 250 kg/m3, the utalization of the brine sludge could be the most.
Composite Solutions for Glulam Joints
Authors: Vodiannikov Mikhail , Kashevarova Galina
Published: May 2019

The current level of the development of composite materials allows producing laminate structures with the desired properties. The application of supercomputer calculation and software systems, numerical modeling methods using finite elements enables the design and analysis of such structures. This article deals with design and calculation methods; the results of the full-scale tests of the joints of glued laminated timber with carbon fiber dowel pins and plates are presented. An overview of the behavior of such structures in corrosive environment and the comparative analysis with traditional steel components are also presented herein. Advantages and disadvantages of glulam joints where composite materials are used are noted. Examples of the joint use of composi\te materials and timber in Russia and internationally are given. Conclusions about the possibilities and ways of using composite materials in the design of wide-spanned glued timber structures are drawn.
FE Analysis of FRP Pressure Vessel
Authors: Srikumar Biradar , Sharnappa Joladarshi , Kulkarni S.M.
Published: May 2019

In this paper the main focus is on analyzing the effect of various parameters like winding angle, winding pattern and fiber volume fraction on the stresses generation in a composite pressure vessel using Finite Element (FE) approach. The present study makes use of three different composite materials namely GFRP (Glass Fiber Reinforced Plastic), CFRP (Carbon Fiber Reinforced Plastic) and AFRP (Aramid Fiber Reinforced Plastic). Further they are compared with metallic pressure vessel (LCS-Low Carbon Steel, Al 6061-T6-Aluminium 6061-T6) to assess their potentiality as a substitute to metallic pressure vessels. Based on Maximum Specific Stress (MSS) results observations it is concluded that optimum parameters suggested for fabrication of pressure vessel are winding angle ±55o, fiber volume fraction, Vf of 0.55 and winding pattern of ((±∅°2)/90°2/(±∅°2)). Following AFRP, CFRP and GFRP provides better performance when compared with LCS and Al 6061 T6 based on MSS value. Considering the availability, cost and application factors it can be concluded that GFRP can be conveniently used as substitute for metallic pressure vessels.
In Vitro Study of Streptococcus mutans Biofilm Formation on Vanillin-Incorporated Orthodontic PMMA Resin
Authors: Thaweboon Sroisiri , Thaweboon Boonyanit
Published: May 2019

Removable orthodontic appliances made of poly methyl methacrylate (PMMA) resin are commonly used after complete orthodontic treatment to keep teeth in the right position and prevent the shift out from the alignment. The use of these appliances can place patients at increased risk of dental caries through the biofilm accumulation of Streptococcus mutans, caries-associated bacteria, on the surfaces of appliance themselves. Moreover, their rough surfaces or intrinsic porosities of PMMA enhance a condition for plaque aggregation, altering the oral microflora and limiting the washing out action of saliva on teeth and mucosal tissues, subsequently bringing about enamel demineralization and gingival inflammation. Cleaning by brushing or using chemical disinfectants is necessary for hygiene maintenance of the appliances, but requires patient cooperation, which is uncertain. Vanillin is a natural phenolic aldehyde which is used widely as a flavoring agent in various foods. It has been reported by many studies to exhibit antimicrobial activity. The aim of the present study was to evaluate antimicrobial property of vanillin-incorporated orthodontic PMMA resin on S. mutans biofilm formation. The self-curing orthodontic PMMA resin samples (SCG Chemicals, Thailand) were prepared according to the percentage of vanillin incorporation (0%, 0.1% and 0.5% vanillin). Another group of commercial resin samples without vanillin (Dentsply Caulk, USA) was prepared in the same manner. All samples were coated with sterile unstimulated saliva collected from three healthy adult volunteers at 37 °C for 60 min. The S. mutans biofilm formation was done with the 107 colony forming unit (CFU)/m of bacterial suspension in 96-well plate and incubated at 37°C in 5% CO2 atmosphere for 24 h. The amount of biofilm was quantified by Cell Counting Kit WST-8 (Dojindo Molecular Technologies, USA) at 450 nm. All tests were performed in triplicate on three separate occasions. One-way ANOVA and Turkey’s test were used for the statistical analysis. A significant inhibitory effect was observed in 0.5% vanillin incorporated samples at 48 h compared with 0% vanillin and commercial samples. The percentage of biofilm reduction was 30%. In conclusion, the incorporation of vanillin to self-curing orthodontic PMMA resin could significantly inhibit biofilm formation of S. mutans. Using this PMMA resin, removable orthodontic appliances with antimicrobial property can be applied to prevent dental caries or tooth demineralization in orthodontic patients.
Banning of Glyphosate and its Impact on Paddy Cultivation: A study in Ratnapura District in Sri Lanka
Authors: Malkanthi S. H. P. , Sandareka U. G. , Wijerathne A. W. , Sivashankar P.
Published: May 2019

Purpose: It is high time to study the impacts of banning of glyphosate in paddy (rice) cultivation in the country as it is important in many aspects of the economy. The quantity of glyphosate has been in use far exceeds the total of all other pesticides especially for paddy cultivation. The government banned glyphosate in order to save Sri Lanka’s agricultural sector especially farmers from the chronic kidney disease (CKD). This unexpected situation has created problems for farmers. This study was conducted to assess the impacts of banning of glyphosate for paddy cultivation in Ratnapura district. Research Method: Ratnapura district was selected as the research area because paddy cultivation has been conducted in many Divisional Secretarial divisions of it. A Sample of 100 paddy farmers was randomly selected and data was collected using a field survey from June to November in 2017. Descriptive statistics and paired t-tests were used to analyze the data. Findings: Results revealed that most of the paddy farmers are male farmers and they are at their middle ages. They have a significant level of education. However, most of them have very small size farm lands and their monthly income is very low. Furthermore, majority of them have a good understanding about positive and negative aspects of glyphosate. Moreover, some farmers are spending much on other herbicides due to unavailability of glyphosate. Hence, there is a significant difference in cost spent for herbicides before and after banning glyphosate. While some farmers are moving away from farming, some farmers are turning to use cultural practices. Originality/ Value: Farmers wish to move away from glyphosate if they have a suitable alternative. But at the moment they are facing problems due to unavailability of alternatives for glyphosate. So that, finding for a better alternative for the glyphosate is a felt need.
How One 11-Page Bill Could Yield Billions in Annual Benefits: The Marijuana Justice Act of 2017
Authors: Dunn Haley
Published: May 2019

Marijuana legalization has gained traction in recent years in the United States with a variety of bipartisan supporters. Primary benefits often cited include savings in enforcement and incarceration costs, additional tax revenue and jobs, release and expungement for those incarcerated, and lowered racial and economic disproportionality in the U.S. criminal justice system. Critics often bring up health costs, increases in impaired driving, harmful effects on adolescent brain development, and greater attendant crime as possible drawbacks.This article examines the potential costs and benefits of federal marijuana legalization under the Senate version of the Marijuana Justice Act of 2017 (S. 1689) introduced in the 115th Congress, assuming 30 additional states legalize recreational marijuana and set up a regulated commercial retail system. Using an analysis that operates under a net present value over 1,000 years and reflects 2017 dollar amounts, the results are overwhelming: these combined efforts could lead to nationwide lifetime net benefits of over $168 billion, with approximately $50 billion in the first year alone, and $17 billion in tax revenue that federal and state governments could receive annually. This article also runs best- and worst-case scenario sensitivity analyses in a postenactmentuniverse—best being one in which all 50 states legalize recreational marijuana and worst being one in which no additional states legalize. Even the worst-case scenario would lead to lifetime net benefits of over $77 billion ($4 billion/year) and, in the best case, over $1.4 trillion ($75 billion/year). For all scenarios, this analysis accounts for the states that have legalized recreational marijuana as of November 5, 2018: Alaska, California, Colorado, Maine, Massachusetts, Nevada, Oregon, Vermont, and Washington.
Privatization of Social Security Retirement Systems: Lessons and Comparisons from Chile, Argentina, and the United States
Authors: Walker Elisa
Published: May 2019

Retirement pensions are traditionally provided through government social insurance systems, which pool risks broadly across the population and provide benefits that are set in law. In contrast, under privatized systems, workers’ benefits depend on their own individual account balances and investment returns, with little or no redistribution and pooling of risk across the population. In 1981, Chile became the first country to fully privatize its social security retirement system, setting an example that Argentina and numerous other countries later emulated. More than two decades later, both Chile and Argentina undertook “re-reforms” to their privatized systems, with Chile maintaining its privatized system while Argentina returned to a fully public system. The United States also confronted efforts to privatize its Social Security system around the same time periods—in the early 1980s and the early 2000s—but ultimately chose to strengthen the existing system rather than privatizing. This article examines and contrasts these three countries’ experiences in the 1980s-90s and 2005-08, probing the factors that led to or prevented privatization. While finances usually provided the stated pretext for reform, privatization is now widely acknowledged to worsen the financial challenges faced by pension systems. Ultimately, neoliberal ideologies were pivotal in putting privatization on the policy agenda, and institutional structures and interest group mobilization helped to shape the outcomes of the privatization effort.
Legislative Gaps in Addressing Rural Women’s Access to Obstetric Care in the United States: A Case Study of the North Carolina Home Birth Freedom Act
Authors: Higgins Isabella
Published: May 2019

Rural women in the United States face numerous barriers to accessing obstetric care. Hospitals and obstetric wards in rural areas are closing, and there is a shortage of rurally-located obstetric care providers. Recent experience in North Carolina provides insight into current legislative barriers to improving rural women’s access to obstetric care. In 2015, legislators in the North Carolina General Assembly unsuccessfully advocated for the Home Birth Freedom Act, which would have allowed certified professional midwives to practice in the state.While the Home Birth Freedom Act would have helped to address rural women’s access to care, it would not have been sufficient. This analysis describes why rural women’s access to obstetric care is limited and offers recommendations to expand access to care by providing certified nurse-midwives with more autonomy, appropriating funds to place obstetric care providers in rural areas, and improving Medicaid reimbursement rates.
Trends of and factors associated with cesarean section related surgical site infections in Guinea
Authors: Delamou Alexandre , Camara Bienvenu Salim , Sidibé Sidikiba , Camara Alioune , Dioubaté Nafissatou , El Ayadi Alison Marie , Tayler-Smith Katy , Beavogui Abdoul Habib , Baldé Mamadou Dioulde , Zachariah Rony
Published: May 2019

Since the adoption of free obstetric care policy in Guinea in 2011, no study has examined the surgical site infections in maternity facilities. The objective of this study was to assess the trends of and factors associated with surgical site infection following cesarean section in Guinean maternity facilities from 2013 to 2015. This was a retrospective cohort study using routine medical data from ten facilities. Overall, the incidence of surgical site infections following cesarean section showed a declining trend across the three periods (10% in 2013, 7% in 2014 and 5% in 2015, P<0.001). Women who underwent cesarean section in 2014 (AOR: 0.70; 95%CI: 0.57-0.84) and 2015 (AOR: 0.43; 95%CI: 0.34-0.55) were less likely to develop surgical site infections during hospital stay than women operated in 2013. In the contrary, women with comorbidities were more likely to experience surgical site infection (AOR: 1.54; 95% CI: 1.25-1.90) than those who did not have comorbidities. The reductions achieved in 2014 and 2015 (during the Ebola outbreak) should be sustained in the post-Ebola context.