bluuebunny/crossref_metadata_2025 huggingface dataset:
B cells reappear less mature and more activated after their anti-CD20–mediated depletion in multiple sclerosis
Authors: Nissimov Nitzan , Hajiyeva Zivar , Torke Sebastian , Grondey Katja , Brück Wolfgang , Häusser-Kinzel Silke , Weber Martin S.
Published: October 2020

Significance

Anti-CD20–mediated B cell depletion is a highly effective therapy in MS. However, long-term effects of this approach on the immune system are not yet characterized in detail. After cessation of anti-CD20 treatment, B cells reappear immature yet highly activated. In addition, anti-CD20 treatment exerts long-lasting effects on T cells, which may be important for its clinical effect. These findings may help in guiding therapeutic decisions with regard to treatment intervals and follow-up therapies.
Pragmatic development during study abroad
Authors: Czerwionka Lori , Olson Daniel J.
Published: October 2020

The current investigation examined the development of second language (L2) intensifier use in spoken Spanish over a 6-week
immersion program in Madrid (n = 45). Native Spanish speakers from Madrid (n = 10) served as a comparison
group to represent the local ambient input or sociopragmatic norm to which L2 learners were exposed. Data were extracted from
semi-structured interviews. Results exposed different developmental trends over the program for intensifier frequency, intensifier lexical
diversity, and intensifier collocations. While learners already had a strong sense of which intensifiers were most frequent in Spanish and
how to use them in appropriate linguistic environments at the beginning of the program, the immersion program had positive impacts on the
development of intensifier frequency and intensifier lexical diversity. The findings also highlighted different intensifier frequency
developmental trends among learners, which collectively suggested that learners adjusted to the sociopragmatic norm of intensifier use in
Madrid over the immersion experience.
A corpus-based analysis of differences in the use ofveryfor adjective amplification among native speakers and learners of English
Authors: Schweinberger Martin
Published: October 2020

This paper analyzes the use ofveryas an adjective amplifier by native speakers and advanced learners of English with diverse language backgrounds based on theInternational Corpus of Learner English(ICLE) and theLouvain Corpus of Native English Essays(LOCNESS). The study appliesMultifactorial Prediction and Deviation Analysis Using Regression/Random Forests(MuPDARF) to find differences between native speakers and advanced learners and evaluates which factors contribute to learners’ non-target-like use ofvery. The analysis finds language background and adjective-specific differences in the use ofverybetween learners and native speakers. It shows that collocational preferences of specific adjective types are the most important factor, which is interpreted to show that differences between native speakers and learners are predominantly dependent upon the collocational profiles of individual adjective types. This finding supports approaches that focus on teaching collocations and contextualizing word use.
Literacies in contact
Authors: Weth Constanze , Böhm Manuela , Bunčić Daniel
Published: October 2020

Research on language contact has so far mainly focused on oral situations, although standardization and language ideologies always have an important influence on multilingualism in both its written and its spoken form. This raises the question of which theoretical models are most suitable for the description of written language contact. The present paper recalls linguistic investigations of written language. Some research on multilingual writing shares concepts with research on oral language contacts, always adapting them for writing. Other research develops new concepts for investigating multilingual writing. Within the framework of research on multilingualism, some concepts approach language contact as a question of systematic interactions between linguistic systems (e.g. borrowing, code-switching, graphematic matrix, schriftdenken), other concepts envisage language contact as a multilingual practice (e.g. translanguaging, multimodal analysis, biliteracy). Written language contact is an especially fruitful field of study for pointing out major differences between these two research traditions and for bridging them.
Assessing environmental impacts in using waste steel slags as construction materials in a highly industrialized area
Authors: Dell’Anna Maria Michela , Romanazzi Giuseppe , Positano Mariangela , Specchio Vito , Mastrorilli Piero , Tomasicchio Giuseppe , Damiani Leonardo , Mali Matilda
Published: October 2020

Steel slags are side products of iron and steel industry and are suitable for a variety of applications. In the present paper, the assessment of the hazard associated with steel slags used as harbor piers backfilling material was performed. The analyses were conducted on 64 samples (soil and groundwater) collected in 17 sites located in one of the piers of Taranto city (South Italy), a highly industrialized area, where steel slags have been used in the past as backfill material. The obtained data were compared to the national threshold levels and International Indexes (Igeo) for assessing anthropogenic impacts. The first comparative analysis revealed that only vanadium in soil and aluminum in groundwater, associated with high pH values in both matrixes (soil and groundwater) resulted of high concern. Nevertheless, Igeo values and the coupling of comparative analysis with multivariate techniques Principal component analysis and Hierarchical Cluster Analyses revealed that also Sb, Pb, Cr and Zn concentration have an extremely high hazard degree. All analyses confirm the impact of steel slags on contaminant leaching processes due to the strong alkaline nature of their leachates and the presence of strong relationship between metal mobility and other physical-chemical parameters related to the peculiar environmental context. These findings suggest that the use of such materials, albeit economically recommended, should be adopted under severe monitoring of all parameters that could promote the mobility of metals and other contaminants.
Coordinate stitching measurement of highly steep freeform surfaces
Authors: Chen Weiwei , Chen Shanyong , Zhai Dede
Published: October 2020

A coordinate measuring machine (CMM) is widely used for surface measurement during milling and grinding of workpieces. However, the measurement uncertainty increases with the surface slope for highly steep freeform surfaces. In addition, local features sometimes exist on the surface out of the accessible space of the CMM. This study presents a coordinate measurement method based on stitching multiple subpatches. The complex freeform surface of a large slope is first divided into subpatches which are individually tilted and measured with smaller uncertainty due to reduced slopes. A global stitching algorithm is then proposed to compensate the motion error and stitch all the subpatches together simultaneously, based on configuration optimization to minimize the overlap inconsistency. The coordinate stitching measurement method is first validated through simulation, which shows that the motion error of the order of 0.05°/0.5 mm is tolerable for a highly steep surface. It is then experimentally verified using the stitching measurement of an optical spherical surface and a steep freeform surface. An ordinary multi-axis adjustment stage is suitable for subpatch repositioning because the stitching algorithm compensates the motion error to a level lower than the CMM uncertainty.
A side-scattering imaging method for the in-line monitoring of particulate matter emissions from cooking fumes
Authors: Zhou Wu , Mei Cong , Qin Jinwei , Cai Xiaoshu , Wang Tianyi , He Wanqing , Shi Aijun
Published: October 2020

To monitor the concentration of particulate matter (PM) from cooking fumes, an in-line measurement method was proposed based on the Lorenz–Mie scattering theory, and a measurement system was developed based on the side-scattering imaging technique with a laser beam for illumination. Polystyrene particles in water suspensions with a known particle size and concentration were utilized for validation. The experimentally obtained gray level of the image of the particle cloud along the laser beam agrees well with that predicted by theoretical model in the same configuration. The artificial fish swarm algorithm was adopted for inversion, and the results of particle size measurements show a standard deviation lower than 5% of the mean measured value at concentrations of 0.5–50 mg · m−3. Using the retrieved particle size distribution, the PM concentrations can be measured with the calculated scattering coefficient k
2 and the measurement system dependent coefficients I
0
k
1. The calibration experiments with polystyrene particle suspensions show a very good linear relationship of the image gray value on the particle concentration. This method makes it possible to monitor the PM concentrations using a non-contact and non-suction approach.
High-temperature intrinsic ferromagnetism in heavily Fe-doped GaAs layers
Authors: Kudrin A V , Lesnikov V P , Danilov Yu A , Dorokhin M V , Vikhrova O V , Demina P B , Pavlov D A , Usov Yu V , Milin V E , Kuznetsov Yu M , Kriukov R N , Konakov A A , Tabachkova N Yu
Published: October 2020

The layers of a high-temperature novel GaAs:Fe diluted magnetic semiconductor (DMS) with an average Fe content up to 20 at. % were grown on (001) i-GaAs substrates using a pulsed laser deposition in a vacuum. The transmission electron microscopy (TEM) and energy-dispersive x-ray spectroscopy investigations revealed that the conductive layers obtained at 180 and 200 ºC are epitaxial, do not contain any second-phase inclusions, but contain the Fe-enriched columnar regions of overlapped microtwins. The TEM investigations of the non-conductive layer obtained at 250 ºC revealed the embedded coherent Fe-rich clusters of GaAs:Fe DMS. The x-ray photoelectron spectroscopy investigations showed that Fe atoms form chemical bonds with Ga and As atoms with almost equal probability and thus the comparable number of Fe atoms substitute on Ga and As sites. The n-type conductivity of the obtained conductive GaAs:Fe layers is apparently associated with electron transport in a Fe acceptor impurity band within the GaAs band gap. A hysteretic negative magnetoresistance (MR) was observed in the conductive layers up to room temperature (RT). MR measurements point to the out-of-plane magnetic anisotropy of the conductive GaAs:Fe layers related to the presence of the columnar regions. The studies of the magnetic circular dichroism confirm that the layers obtained at 180, 200 and 250 ºC are intrinsic ferromagnetic semiconductors and the Curie point can reach up to at least RT in case of the conductive layer obtained at 200 ºC. It was suggested that in heavily Fe-doped GaAs layers the ferromagnetism is related to the Zener double exchange between Fe atoms with different valence states via an intermediate As and Ga atom.
The Role of Magnetic Field Disturbances in the Heating of Active Region Loops
Authors: Asgari-Targhi M.
Published: October 2020

Hot emissions from coronal plasma with T > 4 MK are examined in two active regions observed by the Atmospheric Imaging Assembly (AIA) on the Solar Dynamic Observatory (SDO). The intensity maps in Fe XVIII 94 ˚A are created and the emission intensity in the brightest loops in these regions are measured. The corresponding magnetic maps of these active regions are constructed using the magnetograms from Helioseismic and Magnetic Imager onboard SDO. The photospheric magnetic field is characterized in terms of magnetic disturbances, such as flux emergence and flux cancellations in the surrounding sunspots, and the total magnetic flux is measured. The energy giving rise to high-temperature plasma is found to be deposited in the corona as a result of magnetic reconnection, likely caused by the dynamics of the magnetic field at the photosphere. The observations confirm that the hot plasma is strongly correlated with magnetic flux emergence or cancellation.
A comparison of CME expansion speeds between solar cycles 23 and 24
Authors: Dagnew Fithanegest K , Gopalswamy Nat , Tessema Solomon B
Published: October 2020

We report on a comparison of the expansion speeds of limb coronal mass ejections (CMEs) between solar cycles 23 and 24. We selected a large number of limb CME events associated with soft X-ray flare size greater than or equal to M1.0 from both cycles. We used data and measurement tools available at the online CME catalog (https://cdaw.gsfc.nasa.gov) that consists of the properties of all CMEs detected by the Solar and Heliospheric Observatory’s (SOHO) Large Angle and Spectrometric Coronagraph (LASCO). We found that the expansion speeds in cycle 24 are higher than those in cycle 23. We also found that the relation between radial and expansion speeds has different slopes in cycles 23 and 24. The cycle 24 slope is 45% higher than that in cycle 23. The expansion speed is also higher for a given radial speed. The difference increases with speed. For a 2000 km/s radial speed, the expansion speed in cycle 24 is ∼48% higher. These results present additional evidence for the anomalous expansion of cycle 24-CMEs, which is due to the reduced total pressure in the heliosphere.
Reconnection at the Heliopause: Comparing the Voyager 1 and 2 Heliopause Crossings
Authors: Fuselier Stephen A. , Petrinec Steven M. , Bobra Monica G. , Cairns Iver H.
Published: October 2020

Voyager 1 and 2 observed very different boundary layers adjacent to their respective heliopause crossings. Voyager 1 observed a very thick boundary layer in the inner heliosheath while Voyager 2 observed a very thin boundary layer. Voyager 2 observed a thick magnetic barrier with enhanced total magnetic field in the inner heliosheath while Voyager 1 did not observe a similar barrier. Predicted and observed plasma properties in the inner and outer heliosheath and the magnetic shear at the heliopause crossings are used to investigate the possibility of local reconnection at the heliopause crossings. For the Voyager 1 crossing, local reconnection is suppressed. However, for the Voyager 2 crossing, the magnetic barrier reduced plasma beta in the inner heliosheath and may have facilitated local magnetic reconnection at the heliopause.
Investigating 1st and 2nd order Fermi acceleration of energetic particles by small-scale magnetic flux ropes at 1AU
Authors: le Roux J A , Webb G M , Khabarova O V , Van Eck K T , Zhao L-L , Adhikari L
Published: October 2020

A new telegrapher-type Parker transport equation was derived from the existing underlying focused transport equation to model the acceleration of energetic particles by contracting and reconnecting small-scale magnetic flux ropes (SMFRs) in the large-scale solar wind. Time-dependent and steady-state analytical solutions were found that unify all SMFR acceleration mechanisms present in the transport equation, showing that SMFR acceleration by the parallel reconnection electric field in the mixed spatial and momentum derivative transport term is constrained by and requires the presence of 2nd order Fermi SMFR acceleration. We explore the potential of these solutions in reproducing energetic proton flux enhancements and spectral evolution between ∼50 keV-5 MeV in dynamic SMFR regions near large-scale reconnecting current sheets in the solar wind at 1 AU. It is shown that both 2nd order Fermi SMFR acceleration involving the variance in SMFR compression and incompressible parallel shear flow, and 1st order SMFR Fermi acceleration due to mean SMFR compression are both workable options in reproducing observed flux amplification factors when using reasonable SMFR parameters. However, the predicted substantial quantitative differences in the spatial evolution of the accelerated spectra through the SMFR region might provide a diagnostic to distinguish between 1st and 2nd order Fermi SMFR acceleration in observations.
Large-density (>50 cm−3) heliospheric plasma sheets recorded by the Wind spacecraft between 1995 and 2017
Authors: Liou K , Wu C-C
Published: October 2020

A survey of previous studies of the heliospheric plasma sheet (HPS) suggests a bimodal distribution for the occurrence of the HPS peak plasma density. While the majority of HPS events have a peak density smaller than ∼30 cm−3, there is evidence that large density (>50 cm−3) HPS events can exist. A bimodal distribution would suggest a two-source scenario for the HPS observed at 1 AU. In this study we focus on large density HPS events. We survey the solar wind data acquired from the Wind spacecraft between 1995 and 2017 and identify 108 large-density HPS events with a distribution peak at 55 cm−3, confirming the bimodal distribution. We also find that 80 (74%) of these large-density HPS events are associated with interplanetary shocks. The yearly occurrence of these large-density HPS events nearly follows the yearly occurrence of interplanetary shock. This result suggests that large-density HPS events are likely caused by compression of interplanetary shocks within 1 AU.
Simulations of Magnetised Stellar-Wind Bubbles
Authors: Mackey J , Green S , Moutzouri M
Published: October 2020

Initial results are presented from 3D MHD modelling of stellar-wind bubbles around O stars moving supersonically through the ISM. We describe algorithm updates that enable high-resolution 3D MHD simulations at reasonable computational cost. We apply the methods to the simulation of the astrosphere of a rotating massive star moving with 30km s−1 through the diffuse interstellar medium, for two different stellar magnetic field strengths, 10G and 100G. Features in the flow are described and compared with similar models for the Heliosphere. The shocked interstellar medium becomes asymmetric with the inclusion of a magnetic field misaligned with the star’s direction of motion, with observable consequences. When the Alfv´enic Mach number of the wind is ≤ 10 then the stellar magnetic field begins to affect the structure of the wind bubble and features related to the magnetic axis of the star become visible at parsec scales. Prospects for predicting and measuring non-thermal radiation are discussed.
Intermittency of many-particle dispersion in anisotropic magnetohydrodynamic turbulence
Authors: Pratt J. , Busse A. , Müller W.-C.
Published: October 2020

Intermittent deviation from average dispersion curves reveals differences between the dynamics of magnetohydrodynamic turbulence and hydrodynamic turbulence. Turbulent dispersion is typically measured by the average separation of a group of Lagrangian tracer particles from each other as the particles move in a turbulent flow. On average, the particles will increase their separation as time evolves. However, due to the intermittent nature of turbulence, radical deviations from this behavior can be observed when considering individual groups of particles. When the group consists only of two particles, those two particles sometimes can move toward each other for short periods of time, decreasing their separation. When the group consists instead of many particles that are initially densely packed, similar results can be obtained using the convex hull of the group of particles. We examine this intermittency of many-particle dispersion in incompressible isotropic hydrodynamic turbulence, incompressible isotropic magnetohydrodynamic turbulence, and incompressible anisotropic magnetohydrodynamic turbulence. We interpret periods of decreasing separation physically in terms of anisotropic dispersion due to a large-scale static magnetic field, interactions with local magnetic fields and current sheets, and interactions with Alfvénic fluctuations.
Generalized non-linear Compton-Getting transformation for energetic particles: Applications throughout the heliosphere
Authors: Roelof Edmond C.
Published: October 2020

We develop the theoretical basis for a non-linear frame transformation of energetic ion intensity anisotropies (i.e., a generalized Compton-Getting transformation). Within the basic physics-motivated assumption that the anisotropies are gyrotropic in the transform frame, the rather general formulation allows us to examine a wide range of ion intensity distributions throughout the heliosphere. In addition to generalizing more familiar applications of the Compton-Getting transformation (that utilizes the bulk plasma velocity V for the transformation), we also apply the component (V^) transverse to the magnetic field (B). The physical justification is that (V^) is the ExB drift velocity with which the magnetic field lines “move”. In this paper, we have focused on two quite different areas: the elucidation of the strong field-aligned anisotropies and steep energy spectra being observed near the Sun from Parker Solar Probe (and Solar Orbiter), and the extraction of the bulk plasma velocity in the heliosheath at ∼100 AU using the anisotropies in energetic ion intensities observed on Voyager 1&2.
Interstellar Dust and Gas in the Heliosphere
Authors: Slavin Jonathan
Published: October 2020

Interstellar dust and gas that enter the heliosphere provide us with important clues about both the heliosphere and the local interstellar medium (LISM). The picture we have of the LIC from both in situ detections and absorption line data presents questions that have important implications for the origins and evolution of the cloud. New detections of 60Fe on Earth in deep sea crusts and Antarctic snow cores provide evidence for the role of supernovae in shaping the LISM. We discuss our models for the evolution of the LIC inside the Local Bubble and possible explanations for the source of the supernova produced dust.
Possible Evolution of Minifilament-Eruption-Produced Solar Coronal Jets, Jetlets, and Spicules, into Magnetic-Twist-Wave “Switchbacks” Observed by the Parker Solar Probe (PSP)
Authors: Sterling Alphonse C. , Moore Ronald L. , Panesar Navdeep K. , Samanta Tanmoy
Published: October 2020

Many solar coronal jets result from erupting miniature-filament (“minifilament”) magnetic flux ropes that reconnect with encountered surrounding far-reaching field. Many of those minifilament flux ropes are apparently built and triggered to erupt by magnetic flux cancelation. If that cancelation (or some other process) results in the flux rope’s field having twist, then the reconnection with the far-reaching field transfers much of that twist to that reconnected far-reaching field. In cases where that surrounding field is open, the twist can propagate to far distances from the Sun as a magnetic-twist Alfvénic pulse. We argue that such pulses from jets could be the kinked-magnetic-field structures known as “switchbacks,” detected in the solar wind during perihelion passages of the Parker Solar Probe (PSP). For typical coronal-jet-generated Alfvénic pulses, we expect that the switchbacks would flow pastPSPwith a duration of several tens of minutes; larger coronal jets might produce switchbacks with passage durations ∼1hr. Smaller-scale jet-like features on the Sun known as “jetlets” may be small-scale versions of coronal jets, produced in a similar manner as the coronal jets. We estimate that switchbacks from jetlets would flow pastPSPwith a duration of a few minutes. Chromospheric spicules are jet-like features that are even smaller than jetlets. If some portion of their population are indeed very-small-scale versions of coronal jets, then we speculate that the same processes could result in switchbacks that passPSPwith durations ranging from about ∼2 min down to tens of seconds.
Perpendicular diffusion of solar energetic particles: When is the diffusion approximation valid?
Authors: Strauss R D , van den Berg J P , Steyn P J , Effenberger F J , Wijsen N , Laitinen T , le Roux J A
Published: October 2020

Multi-spacecraft observations of widespread solar energetic particle (SEP) events indicate that perpendicular (to the mean field) diffusion is an important SEP transport mechanism. However, this is in direct contrast to so-called spike and drop-out events, which indicate very little lateral transport. To better understand these seemingly incongruous observations, we discuss the recent progress made towards understanding and implementing perpendicular diffusion in transport models of SEP electrons. This includes a re-derivation of the relevant focused transport equation, a discussion surrounding the correct form of the pitch-angle dependent perpendicular diffusion coefficient and what turbulence quantities are needed as input, and how models lead to degenerate solutions of the particle intensity. Lastly, we evaluate the validity of a diffusion approach to SEP transport and conclude that it is valid when examining a large number of (an ensemble of) events, but that individual SEP events may exhibit coherent structures related to the magnetic field turbulence at short timescales that cannot be accounted for in this modelling approach.
XV Applied Mathematics Meeting and XII Statistics Meeting
Authors: Parra-López H M , Gómez-Vergel C S , Rojas-Suárez J P , Dueñas Ramírez L M
Published: October 2020

The objective of the XV Applied Mathematics Meeting and XII Statistics Meeting was to promote a space for the exchange of knowledge between the academic and industrial sectors and physics; this event is a space to promote reflection and debate on mathematics, statistics, its history, evolution, didactics and application in physics and other sciences. In this meeting, researchers and teachers of mathematics interacted, socialized research results, consolidated networks for the exchange of ideas and successful experiences; moreover, these spaces allowed the strengthening of mathematics and statistics as a science. This science with its pedagogical principles promoted innovation and encouraged the creation of other learning scenarios; these scenarios are oriented to the application of mathematics in various areas of knowledge and to encourage students’ interest in research in these sciences.

List o Organizing Committee, National Scientific Committee, International Scientific Committee, Invited Speakers, Sponsor and Sponsor logos, Partners and Partners logos are also available in this pdf.
Statistical mechanics in the portfolio optimization with Kusuoka’s representation
Authors: Restrepo R , Herrera Y
Published: October 2020

Portfolio optimization under a risk measure consists of finding the efficient curve of the given measure in the plane of expected return vs risk. The portfolios corresponding to points of this curve are portfolios which minimize the risk under the given measure and whose expected total return is greater than a pre-specificied level (benchmark). The optimization problems involved are mostly non-convex and therefore cumbersome. In this paper, we provide a method to approximate the efficient frontier under a law-invariant coherent risk measure by relaxing these optimization problems involved to a finite-dimensional linear model. Our method is based on three tools: the Kusuokas’s representation of the risk measure, the properties of the conditional value at risk functions and the finite elements theory. Finally, we mention the strong connection that the former kind of optimization have with problems in statistical mechanics following the classic framework of simulating annealing.
Use of synthetic polymers of pumice for the removal of chromium in the tannery industry
Authors: Grillo J , Montaño A M , González C P
Published: October 2020

Synthetic inorganic polymers are materials called geopolymers that have structural characteristics used for the removal of contaminants in wastewater. Thanks to its easy synthesis and low production costs, they have become one of the most studied materials in removal processes. In the tannery industry, huge amounts of water are used, which are mixed with chromium salts and whose final disposal is made directly on the water slopes, becoming a serious environmental problem for the world. In this work, geopolymer synthesized with pumice was used to determine the efficiency in the removal of chromium in the wastewater of a tannery in the city of Bucaramanga, Colombia. Initially, aqueous solutions were prepared to study the influence of the contact time, the pH of the initial solution and the dose of adsorbent, on the removal capacity of the metal. The maximum adsorption was presented at nine hours and at a pH value of 4, by comparing the adsorption percentages it was found that the geopolymer has better removal capacity than the precursor material, in turn a study of the sorption kinetics using the Langmuir and Freundlich isotherm model were made. Obtained geopolymer and raw material were characterized by Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscope, before and after the adsorption process.
Physical mechanical performance of asphaltic emulsions in road oil for flexible pavements
Authors: Bastidas-Martínez J G , Ruge J C , Paba I J , Vasquez F , Rojas Suárez J P
Published: October 2020

The present study evaluated experimentally, the impact of the application rate, in terms physical and adherence, of four types of emulsions used as road oiling in two asphaltic layers for flexible pavements. Asphaltic layers are composed by an asphaltic base and a hot mix asphalt surface layer. To evaluate the adherence and physical properties, a shearing test was carried out. Four rapid set cationic emulsions were used, by means of three application rates of 0.33 l/m2, 0.50 l/m2, and 0.65 l/m2 (recommended values in Colombian road construction practices). The results demonstrate that an emulsion application rate of 0.50 l/m2 guarantees better adherence in the structural package. Also, that greater resistance against the sliding of the surfaces of the specimens in the shearing test, depends on the residual content of the asphaltic emulsion.
Improvements in the thermal behavior in the manufacture of the H10 block using coffee husks as an alternative industrial additive
Authors: Sánchez-Zúñiga J V , Sánchez-Molina J , Díaz-Fuentes C X
Published: October 2020

Industrial organic waste reuse in product manufacturing processes is a strategy that strengthens the circular economy. Thanks to materials science, the coffee husk is considered a sustainable alternative that promotes industrial processes optimization in the ceramic industry and contributes to the energy efficiency of buildings. This paper summarizes the behavior of H10 blocks on a laboratory scale in 2 mixtures of clay and coffee husk fired in 3 different temperatures: 900 °C, 1000 °C, and 1100 °C, at the “Centro de Investigación en Materiales Cerámicos, Universidad Francisco de Paula Santander”, Colombia; and evaluates the relationship of physical and mechanical properties with thermal behavior by heat transfer and heat fluxes, simulated in the analysis system software through the finite element method. The results support the improvement of thermal insulation capacity. Due to this, coffee husk combustion generates internal air chambers that increase the porosity of the product. In spite of, physical and mechanical properties contrast thermal benefits with increasing water absorption percentages and thus decreasing the compressive strength of samples. In conclusion, new materials development is a technological advance that expands possibilities to create new solutions for buildings and even improves standardized designs in the ceramic industry.
Design of a portable, low-cost, heliodon prototype for the teaching of solar geometry and irradiance in bioclimatic architecture
Authors: Moreno Peña J R , Contreras Galván B G , Ortega Valencia J C , Pineda Torres J A , Bricio Barrios E E , Arceo Díaz S
Published: October 2020

The design of a portable, low-cost heliodon, developed for didactic purposes, is shown. Students can represent the solar path through the sky, relative to geographical coordinates in any hour and date, by the combined movement of a light source along an arc and its rotation around two different axes. The prototype can be controlled either manually or through a computer application. Following its intrinsic motivation in teaching, this prototype serves to introduce architecture students to bioclimatic architecture, for the design of edifications with a low energy use index, and solar charts, while it can also be a valuable tool in helping to improve the understanding of engineering, physics and astronomy students on topics related to physical computing, solar geometry, irradiance and heat transport.
Real teaching situations to encourage the learning of fractions from physics
Authors: Galvis Burgos M I , Gallardo Pérez H J , Villamizar Jaimes D
Published: October 2020

The research aims to implement real didactic situations for learning fractions and physics in students from educational institutions in “San José de Cúcuta, Norte de Santander, Colombia”. From the theoretical point of view, it starts from one of the ideas that have been emerging in recent times regarding the teaching of physics, such as the development of physical-mathematical thinking by inserting the paradigm of didactic situations into the educational environment. The research is part of a field study, quasi-experimental with self-control. The treatment plan was organized in five didactic situations on theoretical and practical aspects of physics. The results of the pretest reflect deficiencies in the use of mathematical contents associated to the description of physical phenomena in the population under study, which allowed the design and implementation of a pedagogical intervention plan. The post-test showed an increase in the execution of mathematical models in the application to physical phenomena, which inferred the effectiveness of the intervention plan, whose activities allowed innovation in the classroom to achieve the students’ attention. It is concluded that the didactic proposal was an enriching experience with the active participation of the students.
Control panels in human talent processes for professionals in physics in public organizations
Authors: Rojas Suárez J P , Gónzalez Mendoza J , Vergel Ortega M
Published: October 2020

The research follows a cross-sectional inferential quantitative approach, supported by qualitative analysis. Its objective is to evaluate, based on T2 Hotelling, the quality of the human talent process in professionals in physic, through observation of sub-processes and service provided by public servants. The diagnosis was made using the techniques of interview, Delphi and expert audit applied to a sample of 200 users in public institutions in process executed by professionals in physics, and 3 experts in human talent during the year 2019. Results show imaginaries that affect the quality of the process human talent focused on selection of the public servant, bureaucratic processes, waiting time and negative attitudes that affect the perception of these professionals; Bayesian control limits calculated with the distribution of predictive probability posteriori, does not show signs that the process is out of control, but shows three alarms, whose adjustment of parameters through robust methods leads to obtaining a behavior protected from outliers, it was conclusion is that the behavior of the human talent process in institutions and entities in which public servants work in Colombia is under control.
Proposal to evaluate the load capacity of bridges subjected to bending and shear due to living load traffic
Authors: Pino Lobo M , Afanador García N , Guerrero Gómez G
Published: October 2020

This research work reflects the procedure to evaluate the classification factors associated with the load capacity of existing reinforced concrete bridges in Colombia, taking as a case study a bridge simply supported by reinforced concrete with a span of 12 m, determined the physical relationship between the nominal flexion of the element and the flexion due to live load for the bridge under study, for which the established criteria were accepted is the philosophy based on load and resistance factor rating recorded in the manual for evaluation of bridges of the American Association of State Highway and Transportation Officials, concluding that the procedure implemented is consistent with the criteria established in the bridge design manual in Colombia based on the reliable use of statistical factors and the theory of probabilities for the development of bridge designs such structures.
Financial Feasibility Analysis of Jasmine Flower (Jasminum Sambac L.) Farming Business in Batang Regency, Central Java
Authors: Prasetyo Edy , Ekowati Titik , Mukson  , Gayatri Siwi
Published: October 2020

The objectives of the research were to: (i) analyze the productivity of jasmine flower farming business; (ii) analyze the production cost, revenue, and income of jasmine flower farming business; and (iii) analyze the financial feasibility of jasmine flower farming business in Batang Regency. Survey method was used among farmers of jasmine flower in Batang Regency. The sampling method was Purposive Quota Non Probability Sampling Method with the number of samples was 63 respondents. The data was analyzed by descriptive qualitative, descriptive quantitative using statistic i.e. data tabulation, business financial analysis, and analysis of One-Sample t-Test. The result of the research shows that: (i) average scale of jasmine flower farming business in Batang Regency was 0.499 acre/farmer with the productivity of 2,793.86 kg/year, or equal to 5,598.92 kg/acre/year; (ii) the value of jasmine flower farming business income was of Rp 36,999,466.74/0.499 acre/year, or equal to the value of Rp 74,147,277.93/acre/year; and (iii) comparison result with Regency’s Minimum Wage and the Level of Deposit Interest Rate shows that jasmine flower farming business had a potential and was feasible to run and developed in Batang Regency.
Relationship between teat dimensions and milking efficiency by hand milking on dairy cows in Temanggung Regency
Authors: Hartanto Rudy , Listya Damayanti Renita , Sambodho Priyo , Moch Sayuthi Suranto
Published: October 2020

This research was completed at PT. Naksatra Kejora, Temanggung Regency, Central Java Province, Indonesia using 31Holstein Friesian cows (lactation period I-V and lactation month 1-10). The observational method was used in this study. The parameters measured were teat dimensions (teat volume as X1, teat circumference as X2, and teat length as X3) as independent variable and milking efficiency (milking time duration / milk production as Y) as dependent variable. Data obtained were analyzed using correlation, then using linear multiple regression to predict the milking efficiency from teat dimensions. Analysis of variance was used to test the significance of model. The result showed that there was no significant relationship between milking efficiency with teat volume (R = 0.070), teat circumference (R = 0.226) and teat length (R = -0.090). The multiple regression model was Y = 1.141 + 0.003 X1+ 0.050X2- 0.092 X3 (R2 = 0.236, no significant P = 0.061). It was concluded that it was difficult to predict the milking efficiency from teat dimensions on Holstein Friesian cow in Temanggung Regency.
Nitrogen Fertilizer and Microbial Inoculations Determined the Nutrient Uptake and Productivity of Soybean
Authors: Bientri Yunindanova Mercy , Djoko Sulistyo Trijono , Daidi Jauhari Muhammad
Published: October 2020

Soybean is an important commodity in Indonesia. This study aimed to identify the application of microbe inoculations with dosage of N in form of urea toward the growth, N uptake and yield in soybean. This research was conducted on October 2017 to January 2018 in Panunggalan village, Pulokulon, Grobogan, Central Java. It used the Randomized Complete Block Design 2 factors: urea dosages (0; 50; 100 kg ha−1) and microbe inoculations (no inoculation; Rhizobium (R); Rhizobium + Trichoderma (R+T); Trichoderma(T)). The result showed that combination of urea dosage and microbe inoculations significantly influenced plant height and number of trifoliate leaves. Urea dosages and microbe inoculations or combination of both factors did not imply nodulation process. Higher N dosage and microbe inoculations increased N uptake of biomass on vegetative period but had no effect on flowering and pod filling periods. The combination of 100 kgHa-1 urea with microbes or without microbes produced the highest productivity. However, treatment without urea and no inoculation also achieved the highest production. This suggested that there was a native population of Rhizobium bacteria strains that effectively supplied N for plants. Besides, application of urea of 100 kg ha-1 or 46 N kg ha-1 was too small to interfere fixation nitrogen by local Rhizobium population. Therefore, N application in form of anorganic fertilizer or microbe for symbiotic N-fixation was not recommended for existing agro climatic conditions of area with soybean history. Thus, it could simultaneously save the cost of agricultural production.
Drinking and feeding behavior of Ongole Crossbred Heifer with water-free access at MergoAndhini Makmur Farmer Group, Yogyakarta, Indonesia
Authors: Baliarti Endang , Astuti Andriyani , Wiandita Arsy , Listia Astrini Astrid
Published: October 2020

This study was aimed to determine the effect of the water-free access on drinking and feeding behavior of Ongole Crossbreed (OC) heifer in the Mergo Andhini Makmur farmer group in Bolu Village, Yogyakarta, Indonesia. Ten OC heifers with an average body weight of 280 kg divided into two treatment groups. The first treatment (P0) gave water according to the farmer used to give (control group), while the second group (P1) with water-free access. The feed given was forage and concentrate. Feeding and drinking behavior which were feeding duration, frequency of eating, drinking, urination, and defecation during 7 consecutive days were collected then analyzed by One Way ANOVA to see if there were differences between two group of water accessed. The results showed that the frequency of drinking of free access water group was higher (P<0.05) compared to the control group (5.9 ± 2.6 vs 1.00 ± 0.00 times/day), while duration and frequency of eating, frequency of urination, defecation and amount of defecation and urination were not significantly different (P>0.05). The results of this study concluded that Ongole Crossbred heifer needs water-free access than those restricted ones for better performances.
Effectiveness of Acidifier in Broiler Fed Diet Double Step-Down Protein
Authors: Djauhari Mahfudz Luthfi , Adi Sarjana Teysar , Kismiati Sri , Muryani Rina , Hamonangan Nasoetion Maulana , Suthama Nyoman
Published: October 2020

Research’ aim was to determine the effectiveness of acidifiers in broiler fed double step-down protein. A total of 168 birds (84 males and 84 females, initial BW was 186.3 ± 0.68 g) were raised for eight weeks. The first 7 days, chickens were fed on commercial feed. Experimental diets were composed to contain protein and energy of 21.41% and 2.856.91 kcal/kg, for starter control diet, and of 19.15% and 2884.12 kcal/kg for starter dietary protein step-down similar to finisher control diet, and of 17.37% and 2882.13 kcal/kg for finisher protein step-down diet, respectively. The study was arranged in a completely randomized design with seven treatments and four replications (6 birds each). Parameters measured were feed and protein consumptions, protein digestibility, body weight gain, feed conversion, and income over feed cost. Data were analysed by variance and to Duncan multiple range test. The results showed that dietary inclusion of acidifiers lowered feed and protein consumptions, but it increased body weight and income over feed cost as well as improved feed conversion. In conclusion, acidifiers inclusion, especially at the level of 0.8% synthetic citric acid, in the double step-down protein can increase efficiently broiler performance and improves income over feed cost.
Evaluation of herbal antiseptic red teak leaf extract (Tectona grandis Linn. F.) as teat gel for dairy cow
Authors: Suselowati Tituk , Sitha Irma Yuhanita Susan , Ardiansyah Prasetyo , Wahyu Harjanti Dian
Published: October 2020

Antiseptic application on cow’s teat after milking is essential to prevent the udder infection during milking. This study aimed to evaluate the antibacterial effectiveness of Tectona grandis leaves extract as the main ingredient of antiseptic gel for cow’s teat as the innovation from conventional antiseptic solutions. The effects of herbal gel antiseptic on milk quality and the level of mammary inflammation (mastitis) were also determined. The mammary inflammation level determined by California Mastitis Test (CMT). Total of four sub-clinical mastitis cows (sixteen teats) were used in the completely randomized design split plot in time (four treatments and four replications). The main plots were the red teak leaves extract with different levels: 0.10% (P1); 0.06% (P2); 0.02% (P3) and povidone iodine (P0) as positive control. The sub-plot was the duration of treatments (0, 5 and 10 days). The result showed that bacterial counts in milk from cows using herbal antiseptic gel (P1, P2, P3) were lower (P<0.05) than those using povidone iodine (P0). The bacterial counts in milk and the mammary gland’s inflammation degree were significantly decreased (P<0.05) as the treatment duration increased. There were significantly difference on the level of mammary inflammation healing between cows using herbal antiseptic gel and povidone iodine. The decreased level of mammary inflammation was thought to have an effect on increasing the protein, fat, and lactose contents in milk of cows using herbal gel (P<0.05). Hence, the antiseptic gel with the lowest dose (0.02%) has the potential for use as anti-inflammatory agents.
Indonesian maize imports: a gravity approach
Authors: Arifah Purnamasari Siti , Masyhuri  , Handoyo Mulyo Jangkung , Jamhari
Published: October 2020

The implementation of the ASEAN Economic Community (AEC) will affect the trade flow of goods and services in the ASEAN region. The flow of food from surplus countries to the food-insecure countries will improve national food security. The purpose of this study is to investigate the factors that affect Indonesia’s maize Import in ASEAN trade. The study analyzed the annual data from 1990 to 2016 and cross-section ASEAN member countries, as well as Indonesia’s trading partners such as Malaysia, the Philippines, Thailand, Vietnam, Myanmar, and Singapore. The study applies the Gravity model approach to identify factors that influence maize import in Indonesia. The panel data regression applied to the fixed-effect method. The results show that Indonesian maize imports were influenced by growth in GDP per capita, economic distance, import tariffs, the exchange rate of the Rupiah against the Dollar, the implementation of AEC (ASEAN Economic Community), non-tariff barriers, and the population growth. All the independent variables together affected Indonesian maize imports from Southeast Asia. The empirical results of this study reveal the implications for the development of the production and competitiveness of Indonesian maize. The Indonesian government should strive to increase farm productivity and efficiency to increase maize production.