bluuebunny/crossref_metadata_2025 huggingface dataset:
Pebble drift and planetesimal formation in protoplanetary discs with embedded planets
Authors: Eriksson Linn E. J. , Johansen Anders , Liu Beibei
Published: February 2020

Nearly axisymmetric gaps and rings are commonly observed in protoplanetary discs. The leading theory regarding the origin of these patterns is that they are due to dust trapping at the edges of gas gaps induced by the gravitational torques from embedded planets. If the concentration of solids at the gap edges becomes high enough, it could potentially result in planetesimal formation by the streaming instability. We tested this hypothesis by performing global 1D simulations of dust evolution and planetesimal formation in a protoplanetary disc that is perturbed by multiple planets. We explore different combinations of particle sizes, disc parameters, and planetary masses, and we find that planetesimals form in all of these cases. We also compare the spatial distribution of pebbles from our simulations with protoplanetary disc observations. Planets larger than one pebble isolation mass catch drifting pebbles efficiently at the edge of their gas gaps, and depending on the efficiency of planetesimal formation at the gap edges, the protoplanetary disc transforms within a few 100 000 yr to either a transition disc with a large inner hole devoid of dust or to a disc with narrow bright rings. For simulations with planetary masses lower than the pebble isolation mass, the outcome is a disc with a series of weak ring patterns but there is no strong depletion between the rings. By lowering the pebble size artificially to a 100 micrometer-sized “silt”, we find that regions between planets get depleted of their pebble mass on a longer time-scale of up to 0.5 million years. These simulations also produce fewer planetesimals than in the nominal model with millimeter-sized particles and always have at least two rings of pebbles that are still visible after 1 Myr.
A hot terrestrial planet orbiting the bright M dwarf L 168-9 unveiled by TESS
Authors: Astudillo-Defru N. , Cloutier R. , Wang S. X. , Teske J. , Brahm R. , Hellier C. , Ricker G. , Vanderspek R. , Latham D. , Seager S. , Winn J. N. , Jenkins J. M. , Collins K. A. , Stassun K. G. , Ziegler C. , Almenara J. M. , Anderson D. R. , Artigau E. , Bonfils X. , Bouchy F. , Briceño C. , Butler R. P. , Charbonneau D. , Conti D. M. , Crane J. , Crossfield I. J. M. , Davies M. , Delfosse X. , Díaz R. F. , Doyon R. , Dragomir D. , Eastman J. D. , Espinoza N. , Essack Z. , Feng F. , Figueira P. , Forveille T. , Gan T. , Glidden A. , Guerrero N. , Hart R. , Henning Th. , Horch E. P. , Isopi G. , Jenkins J. S. , Jordán A. , Kielkopf J. F. , Law N. , Lovis C. , Mallia F. , Mann A. W. , de Medeiros J. R. , Melo C. , Mennickent R. E. , Mignon L. , Murgas F. , Nusdeo D. A. , Pepe F. , Relles H. M. , Rose M. , Santos N. C. , Ségransan D. , Shectman S. , Shporer A. , Smith J. C. , Torres P. , Udry S. , Villasenor J. , Winters J .G. , Zhou G.
Published: February 2020

We report the detection of a transiting super-Earth-sized planet (R= 1.39 ± 0.09R⊕) in a 1.4-day orbit around L 168-9 (TOI-134), a bright M1V dwarf (V= 11,K= 7.1) located at 25.15 ± 0.02 pc. The host star was observed in the first sector of the Transiting Exoplanet Survey Satellite (TESS) mission. For confirmation and planet mass measurement purposes, this was followed up with ground-based photometry, seeing-limited and high-resolution imaging, and precise radial velocity (PRV) observations using the HARPS andMagellan/PFS spectrographs. By combining the TESS data and PRV observations, we find the mass of L 168-9 b to be 4.60 ± 0.56M⊕and thus the bulk density to be 1.74−0.33+0.44times higher than that of the Earth. The orbital eccentricity is smaller than 0.21 (95% confidence). This planet is a level one candidate for the TESS mission’s scientific objective of measuring the masses of 50 small planets, and it is one of the most observationally accessible terrestrial planets for future atmospheric characterization.
Pal 13: its moderately extended low-density halo and its accretion history
Authors: Piatti Andrés E. , Fernández-Trincado José G.
Published: February 2020

We present results based on Dark Energy Camera Legacy Survey (DECaLS) DR8 astrometric and photometric data sets of the Milky Way globular cluster Pal 13. Because of its relatively small size and mass, there is not yet a general consensus on the existence of extra-tidal structures surrounding it. While some previous results suggest the absence of such features, others show that the cluster is under the effects of tidal stripping. We have built a cluster stellar density map from DECaLS g, r magnitudes – previously corrected for interstellar reddening – of stars placed along the cluster main sequence in the color-magnitude diagram. The resulting density map shows nearly smooth contours around Pal 13 out to approximately 1.6 t the most recent estimate of its Jacobi radius, which was derived whilst taking into account the variation along its orbital motion. This outcome favors the presence of stars escaping the cluster, a phenomenon frequently seen in globular clusters that have crossed the Milky Way disk a comparably large number of times. Particularly, the orbital high eccentricity and large inclination angle of this accreted globular cluster could have been responsible for the relatively large amount of lost cluster mass.
Characterization of the mineralization of the Groundwater in high Basin of Guir (Morocco) by geochemical and geostatistical
Authors: Nordine Nouayti , Abderrahime Nouayti , Driss Khattach , Mohamed Hilali , Najib El khadrani
Published: February 2020

Due to over-exploitation of water resources, the high basin of Guir posed an alarming risk of elimination in terms of quantity and quality. Therefore, this study intends to evaluate the physical and chemical quality of groundwater in the high Basin of Guir and to identify possible sources of pollution in order to map the quality of the Jurassic groundwater. During May 2018, thirty water points, distributed in the high basin of Guir, were sampled and analysed to determine concentrations of sevenchemical elements: K+, Na+, Ca++, Mg++, Cl-, HCO3-, SO4-. In addition, EC (Electric Conductivity), pH,T° and the piezometric level (PL) weremeasured.To study and compare, we treated statistically all data by Principal Component Analysis (PCA) and SIG.Analysis of the overall quality of water displayed results that range from good to poor quality. The degradation of water quality in the aquifer of the high basin of Guir could be geological and anthropic.
Study of coupling photocatalysis and membrane separation using tubular ceramic membrane made from natural Moroccan clay and phosphate
Authors: El Baraka Noureddine , Laknifli Abdellatif , Saffaj Nabil , Addich Mourad , Ait Taleb Abdelaziz , Mamouni Rachid , Fatni Abdelilah , Ait Baih Mohamed
Published: February 2020

This paper is devoted to study the feasibility of combining photocatalytic degradation with membrane filtration for the removal of organic pollutants. As a result, we have successfully prepared low-cost microfiltration membranes based on clay and phosphate. It is expected that the phosphate and clay composite membrane can have multifunctional separation and photocatalysis simultaneously and this type of composite membrane can play an important role in the photocatalytic reaction in presence of TiO2 and the separation process. We then tested the efficiency of the direct coupling of photodegradation and filtration to determine the rate of release of TiO2 particles through the microfiltration membrane. However, we have seen that the recovery of TiO2 exceeds a 96%, as well as the removal of products from the photodecomposition of the reaction mixture in the membrane photocatalytic reactor. In our case the methylene blue elimination rate exceeds 75%.
Impact of climate change on pavements
Authors: Hemed Ahmed , Ouadif Latifa , Bahi Lahcen , Lahmili Abdelaziz
Published: February 2020

Climate change is reflected in changes in average weather conditions and the more frequent occurrence of extreme conditions. It also affects the field of road transport and shows impacts both on traffic and road users as well as on the road infrastructure itself.

The main objective of this work is therefore to evaluate the impact of climate change on the performance of road infrastructure (pavements) and to educe recommendations through proposals for adaptation measures.

The impacts of climate change on road infrastructure result in changes in some road design parameters (average temperatures, radiation index, etc.).

The different cases of cracking (fatigue or other) are assessed separately using degradation indices for each layer composing a pavement (surface layer, base layer, stabilized layer, etc.)
The influence of curing temperature, plastic additives and polypropylene fibers on the mechanical behaviour of cementitious materials
Authors: Aqil Mohammed , Bahi Lahcen , Ouadif Latifa , Belhaj Siham , Edderkaoui Raounak
Published: February 2020

An experimental company was carried out to better understand the influence of curing temperature on the mechanical behaviour of cementitious materials, particularly compressive strength, the study focused on two types of mortars, the first containing polypropylene fibers while the second contains a proportion of PVC-type plastic grains from industrial waste, the hydration kinetics of the different components of the formulated mortar has been characterized by the isothermal calorimetric test, thus a history of the hydration degrees has been established, Afterwards, an attempt was made to correlate the compressive strength with the evolution of the degree of hydration for the different formulations, based on the results obtained, it is clearly observable that the compressive strength evolves with the degree of hydration and that the specimen containing the polypropylene fibers has the best mechanical performance with respect to compression.
Physicochemical characterization of leachates produced in the Rabat-Salé-Kénitra Region landfill technical center and monitoring of their treatment by aeration and reverse osmosis
Authors: El Jalil Mounaim Halim , Elkrauni Hind , Khamar Mohamed , Bouyahya Abdelhakim , Elhamri Hecham , Cherkaoui Essediya , Nounah Abderrahman
Published: February 2020

The aim of this work is to study the physicochemical characterization and monitoring of the treatment of leachate generated by the landfilling of household and similar waste in the landfill of Rabat-Salé-Kénitra Region. The analysis of the results showed a high concentration of easily biodegradable organic matter. The pollutant load is of the order of 3,850 mg/L of the chemical oxygen demand (COD), 1.260 mg/L of the biochemical oxygen demand (BOD5), and shows an average content of nitrates (NO3-=56.6 mg/L). This mineral pollution is caused by a high electrical conductivity, which reaches an average value of 15.9 mS/cm, and a low concentration of heavy metals in the raw leachate such as lead (Pb = 1.591 mg/L), copper (Cu = 1.017 mg/L), and cadmium (Cd = 0.109 mg/L). The biological treatment allows for the successive biodegradation of 40% of the BOD5, and 33% of the COD. Moreover, the reverse osmosis filtration in organic membranes achieves a reduction of 98% for BOD5, 97% for COD, 85% for lead, and 67% for copper. In this study, biological and reverse osmosis treatments represented an effective treatment for the organic and metallic leachate pollutants of this landfill.
Recycled thermoplastics modified bitumen improved with thermoplastic elastomer
Authors: Akkouri Nacer , Baba Khadija , Simou Sana , ELfarissi Latifa , Nounah Abderrahman
Published: February 2020

The use of different types of recycled plastic waste such as recycled polypropylene (PP), recycled low-density polyethylene (LDPE) and recycled polystyrene (PS), as raw materials for bitumen modification is known. However, the mechanical and thermal properties of recycled plastic waste modified bitumen (RPMB) are lower than those of the pure plastic modified bitumen. Therefor this paper aims to study the mechanical and thermal properties improvement of the RPMB with the use of a commercial elastomer styrene-butadiene-styrene (SBS). Initially conventional 35/50 quality bitumen was mixed with different percentages of LDPE, PS and PP, and then doped with commercial SBS. Basic rheological parameters such as penetration, softening point, elastic recovery and penetration index showed the changes caused by each rate of polymer addition to pure bitumen. The tests showed that the penetrability of the modified bitumen decreases and its softening point and elastic recovery increases, resulting in a decrease in the thermal sensitivity of the new bitumen mixture.
Verification of the technical feasibility of composting: case study
Authors: Edderkaoui Raounak , Khomsi Driss , Hamidi Ahmed , Bennani Baiti Hicham , Souidi Hanane , Aqil Mohammed
Published: February 2020

The aim of this work is to verify the technical feasibility of composting in the case of Marrakech prefecture. On the basis of waste composition and in accordance with the choice of the installation of Marrakech controlled landfill, composting has been considered as the most suitable waste treatment.

To ensure the feasibility of composting, physicochemical analyses have been carried out on the fermentable part of waste; analyses on the content of metal elements have also been performed on the fine fraction, since the most important part is located in the same fraction. All parameters determined in the laboratory, have shown that optimal conditions to have good quality compost have been respected. The only restriction identified is the copper content, which should be less than 20 ppm. Generally the low levels of metal element content indicate that the storage and collection conditions of waste have not influenced their quality. On the other hand, the process must be properly controlled and managed, to produce high-quality compost.
Production of a Curve Number map using GIS Techniques in the watershed of the high Sebou (Morocco)
Authors: Jabri Btissam , Hessane Mohammed Abdelbaset
Published: February 2020

This work focusing on the collection and preparation of necessary data for hydrological modeling of High Sebou watershedupstream of the dam Allal El Fassi. It describes a methodology for combining space technologies, including geographical information systems (GIS), remote sensing and digital terrain models (DTM), with hydrological models with a view to prepare for a spatial hydrologic modeling whose used for flood forecasting.

The methodology for conducting this study comes in several parts:

The collection and processing of geographic data constituted the first part of this project. This approach is, in the beginning, to automatic extraction of sub-basins and drainage network, then the formatting of data for the mapping of the basin and finally, the preparation of the land use and soil for the development of a map of Curve Number (CN).
Effect of no tillage on the physico-chemical properties of soils of the El Koudia region, Rabat (Morocco)
Authors: Maher Hassnae , Moussadek Rachid , Zouahri Abdelmjid , Douaik Ahmed , Dakak Houria , El Moudane Mouloud , Ghanimi Ahmed
Published: February 2020

In Morocco, agriculture is an important sector of the economy, accounting for 15 to 20% of Gross Domestic Product. However, it has faced several challenges: intensive tillage of land that has accelerated water erosion, seriously threatening water and soil potential, low plant cover density and misuse of traditional agricultural practices, causing a decrease in organic matter levels and destroying aggregate stability. Climate change is making water and soil management in agriculture more and more complicated. The major challenge for Moroccan agriculture is to increase agricultural production while preserving natural resources. The objective of our study is to evaluate the effect of no tillage (NT) on the physico- chemical properties of soil in the El Koudia experimental station, Rabat, Morocco. The crop is durum wheat, Arrehane variety. Soil samples are pre-dried, ground and screened to 0.2mm for organic matter (OM) analysis and 2mm for the remainder of the analyses. Plugs, canned, are then sintered, screened and dried for structural stability tests. The results show that no tillage (NT) favours the accumulation of surface OM, particularly at the 0-5cm horizon unlike conventional tillage (CT). The NT promotes structural stability, with a mean weight diameter (MWD) = 0.94mm for the NT compared to 0.83mm for the CT. These results show that soils ploughed in CT are more exposed to erosion degradation than soils not ploughed (NT). In addition, NT preserves soil moisture and promotes additional water retention of 5 to 10%.
Study of soil erosion risks using remote sensing in Ouergha River watershed (Morocco)
Authors: Jaouda Imane , Akhssas Ahmed , Ouadif Latifa , Bahi Lahcen , Elkasri Jada , Souidi Hanane , Soussi Halima
Published: February 2020

The watershed Ouergha River located in the north of Morocco suffer from vegetation cover degradation, this geographic entity is experiencing intense water erosion linked to the combination of several natural factors, such as the roughness and abundance of rainfall and the predominance of soft geological formations. Human intervention in this vulnerable environment accentuates its fragility by the clearing and degradation of the vegetation cover and the cultivation of land with a steep slope.

This work aims to map the spatiotemporal evolution of this degradation by using the spot and Landsat images and the Radar image over a period from 1990 to 2014 data and aims to model its processes of erosion.

In fact, the analysis of satellite data identified six main types of land use (eau, foret, reboisement…). It has also shown that the most degraded soils aren’t necessarily those with the greatest erosion rates over the past 15 years and that some soils that have developed well over time have become major exporters of sediments after clearing and cultivation.

The comparison of the results of land use has highlighted the harmful impact of human practices on the acceleration of soil degradation.

Human intervention, coupled to frequent and severe drought periods, remain the most important factors in the weakening and increasing vulnerability of soils to degradation.

The results obtained by this approach made it possible to identify and monitor vulnerable areas at Ouergha watershed where interventions are needed to limit the processes of degradation of the soil and the natural environment.
A Combined Probabilistic Approach for Natural Hazards Assessment of Soil-Sewer Pipes (S-SP) Systems
Authors: KaziTani Nabil
Published: February 2020

The structural failure prediction of underground sewer pipes systems seems very complicated due to the natural hazards of soils in which these elements are buried. The apparition of first cracks and notches in sewer pipes parts is governed by the interaction model of soil-sewer pipes system (S-SP)parameters mainly, the constitutive material laws of soil and sewer pipe materials. The detection of critical sections where the structural damages are highly probable is the focus point of this present study. Based on probabilistic analysis of stochastic modelling results (Monte Carlo Method) of random soil properties, the mechanical behaviour of a part of sewer pipe is analysed in terms of settlements and flexural stress distribution fluctuations. A parametric study is performed to quantify the effect of correlation length (Lc) and soils types on the structural reliability of underground sewer pipes. This current structural analysis offers to engineers and researchers a useful numerical tool in order to allow them the well understanding of the structural behaviour of buried sewer pipes by considering the spatial variability of soil geo-mechanical characteristics which reflects the soil natural process of formation, its aggregation and heterogeneity. The obtained numerical results show that the probabilistic analysis of the spatial variability of soil properties into structure numerical modelling of sewer pipes presents an accurate approach for the prediction of structural responses of waste water transportation infrastructures particularly, if the sewer pipe lengths are relatively significant and buried into several classes of soils along sewer pipe networks.
Characterisation of Recent and Future Climatic Trends in the Region of Guelmim (Morocco)
Authors: Amouch Said , Akhssas Ahmed , Bahi Lahcen , Bennouna Rhita
Published: February 2020

According to the Intergovernmental Panel on Climate Change (IPCC), climate change is manifested by the increase in average surface atmospheric temperatures and a decrease in rainfall. The impacts are multiple, complex and differentiated from one region to another in the world. In the Guelmim region (southern Morocco), climate change is manifested by severe droughts and/or recurrent floods. The objective of this study is to characterize the recent and future climate variability in the Guelmim region based on time series of precipitation, the study period goes from 1985 to 2017, and from 2020 to 2099 using Standardized Precipitation Index (SPI).Results of SPI analysis indicate that the most notable droughts for their varying intensity, duration and frequency occurred during the 1992-94 and 1997-2000 periods. Future analysis indicates the study area will face several extended periods of drought and wet during 2020 to 2099. The results of this study show also the link between North Atlantic Oscillation and winter precipitation in Guelmim, which are associated with the negative phase of NAO. The purpose of the study is to have a good management of crops and water resources in Guelmim region and either to insure a sustainable management of environment.
Stability of a rock mass using the key block theory: a case study
Authors: Zerradi Y. , Lahmili A. , Souissi M.
Published: February 2020

In underground mines, excavating disturb the initial equilibrium state of the rock mass, and therefore require selection of a support in order to control the movement of rocks, avoid landslide and work safely. Thus, the progress of mining operations in the ST2 mineralization, in the eastern zone of the Bouazzer mine, is disrupted because of stability problems. On the basis of field observations and analyzes of core drill, the geological and structural study, carried out in this area, has shown the existence of three types of facies: altered and cracked diorite, cobaltiferous mineralization which is in contact with serpentinites. In fact, the empirical methods such as Barton, Bieniawski and the recommendations of the AFTES have qualified the rock mass as poor, furthermore they proposed as kind of supports: steel arches, shotcrete and rock-bolts. Numerical simulation by the finite element method proved to be very complex due to existence of several types of discontinuities (faults, shistosities and joints).These discontinuities are natural fractures that delimit various shapes and sizes of wedges, which can become detached from the roof or siding of the excavation and collapse under their own weight. Although the empirical methods cited above provide supports for each facies, however, this support is expensive and difficult to implement in practice because it must cover the entire surface of the excavation and thus not allowing to detect stable blocks that do not require a support. For this it was essential to carry out an analysis of wedges to better locate unstable blocks. The treatment of fracturing data has highlighted the presence of five sets of discontinuities of which three sets are principals and the other two are minor joints. Then, while taking into account the geometrical, mechanical data of the discontinuities as well as the geometrical data of the excavation, we were able to detect the shape and the size of the unstable blocks and the sets of discontinuities delimiting them and which favor their sliding and tilting. Thus, we calculated the number of anchor bolts needed to stabilize these blocks in order to ensure an acceptable safety factor. This study shows clearly how a wedge analysis of the rock mass can guide and optimize the support work.
Estrus Synchronization Using Prostaglandin F2α (PGF2α) and Combination of PGF2α and Gonadotropin-Releasing Hormone In Ongole Crossbred
Authors: Astuti Pudji , Airin Claude M. , Widiyanto Slamet , Sarmin Sarmin , Hana Amelia , Maheshwari Hera , Sjahfirdi Luthfiralda
Published: February 2020

The response of estrus can be enhanced by providing PGF2α and a combination of PGF2αGnRH so that the time of mating using Artificial Insemination (AI) can be held precisely. This study aims to compare the response of estrus synchronization using PGF2α compare to PGF2α-GnRH. Twenty female cattle Ongole Crossbreds, 4-6 years, BCS average of 3-4 were used in this research. Cattle were selected based on their luteal phase at the days of 7 to 18 by rectal examination. Then, all of the cattle were injected by cloprostenol® with a dose of 500 ug intrauterine. Ten of the animals were injected by 2.5 mL of Fertagyl® intramuscularly after 48 hours then continued observing and response estrus detection. The onset of estrus using PGF2α was detected on 75.94 ± 0.78, while 41.57 ± 28.40 hours for PGF2α-GnRH Using statistical, there was a significant difference (P<0.05). Duration of estrus phase using PGF2α was 24.65 ± 0.49 whereas PGF2α-GnRH was 10.88 ± 7.45 hours. Using statistical methods, there was a significant difference (P <0.05). It could be concluded that the use of PGF2α was more effective for the duration and intensity of estrus, and a combination of PGF2α -GnRH is more effective for stimulating estrus.
Who’s Responsible? Issues in Eradicating Marine Litter In Aceh Jaya Regency
Authors: Kusumawati Ika , Setyowati Mita , Syakti Agung D. , Fahrudin Achmad , Marefanda Nodi
Published: February 2020

Marine debris is any persistent, manufactured or processed solid material discarded, disposed of or abandoned in the marine and coastal environment. Debris problem in coastal areas becomes an urgent issue and concerns many countries across the world particularly marine countries such as Indonesia. The research objective was to examine the people's perception towards marine litter in Aceh Jaya Regency about whom responsible for eradicating marine debris. The study was conducted from January to July 2019 by distributing a questionnaire to 382 respondents. The result showed that 46.9% of respondents thought that they were responsible for reducing marine litter. In a similar case, researchers found 53.4% of respondents stated that those who were able to reduce marine waste were community/visitors. The final finding is that 42.1% of the sample shows that NGOs are the parties who are eager to reduce marine litter.
Occurrence of Fasciola gigantica and Paramphistomum spp Infection in Aceh Cattle
Authors: Hambal Muhammad , Ayuni Rizka , Vanda Henni , Amiruddin Amiruddin , Athaillah Farida
Published: February 2020

Fasciola gigantica and Paramphistomum spp. are trematode helminth causing severe economic losses in cattle farming in Aceh Province, Indonesia. This study was conducted to examine the correlation between the prevalence of F. gigantica and Paramphistomum spp infections with the body condition and sex of Aceh cattle. In total, 103 cattle (50 males and 53 females) from an abattoir in Banda Aceh were used. The body condition score was recorded and the number of fluke eggs in feces was examined coproscopically. The results showed that F. gigantica prevalence was 41% and 72% in females and males, respectively, whereas, the prevalence of Paramphistomum spp in females and males was 81% and 72%, respectively. The average number of fasciola eggs was 2.55 eggs/ g feces and 2.75 eggs/ g feces in females and males, respectively, The average number of Paramphistomum spp eggs was 127.6 eggs/g feces and 36.8 eggs/ g feces in males, and female respectively. Based on the Body Condition Score (BCS), the prevalence of both trematodes was higher in the skinny cattle (BSC 2 and 3). This study established that the infection of Fasciola in BCS 3 was higher than BCS 2 and 4. Male cattle were more susceptible to infection than females.
Growth Patterns Crassostrea sp in Various Cultural Media of Marine Water Area, Banda Aceh
Authors: Arja Fauzi , Sarong Muhammad A. , Suhendrayatna Suhendrayatna , Huda Ismul
Published: February 2020

Oysters belong to the bivalve class, which has a soft body and is protected by two hard shells. Living in groups and sticking together on various substrates. Oysters have high nutritional content so that the need for oysters continues to increase unbalanced with the availability of oysters in the habitat. The study aimed to see the pattern of growth of various culture media of oysters. The research was carried out from May until June 2019. Samples were taken in three water areas based on cultivation media with a purposive sampling technique when the water receded, and data analysis was carried out in the Laboratory. Oysters from cultivation media showed the growth pattern (b = 0.47 to 0.65) with a coefficient of determination (R2 = 0.25 to 0.83) while oysters without cultivation media showed growth pattern (b = 0.44 to 0.51) with the coefficient of determination (R2 = 0.19 to 0.27) and all show allometric negative growth patterns (b <3). The results of the value of b and the coefficient of determination obtained in the culture media are greater than the values obtained without the cultivation media, which shows that the use of cultivation media is very effective in oyster production.
Effect ofAloe veraExtract in Reducing Formaldehyde in Salted Squid (Loligo indica)and Sensory Evaluation
Authors: Safrida Safrida , Syafrianti Devi , Haryani Irma
Published: February 2020

This study aims to determine the effect ofAloe veraextract in reducing formaldehyde levels in salted squid and determine the organoleptic characteristics of salted squid after being givenAloe veraextract. This study used a completely randomized design (CRD) with 4 treatments and 6 replications: P0 (0%Aloe veraextract), P1 (10%Aloe veraextract), P2 (20%Aloe veraextract), and P3 (30%Aloe veraextract). Data were analyzed by using an analysis of variants at a significant level α = 0.05 followed by Duncan's Test. The average formalin content before given aloe vera extract in P0, P1, P2, P3 was 3.65 mg / L, 4.08 mg / L, 4.09 mg / L, 3.96 mg/ L, respectively and after being given aloe vera extract was 2.75 mg/L, 2.58 mg / L, 1.63 mg / L, 2.82 mg / L, respectively. Administration ofAloe veraextract showed a significant reduction of formaldehyde levels in salted squid (p<0.05). Moreover, it was affecting the quality of salted squid in terms of color, aroma, and texture. It can be concluded that the administration of 20%Aloe veraextracts effective for reducing the formaldehyde levels, improve the quality of color, aroma, and texture in salted squid.
Potential of Flamboyant Flower (Delonix regia(Boj. ex Hook) Raf) Extract to Maintain Post-Dilution Quality of Aceh Cattle (Bos taurus indicus) Spermatozoa
Authors: Muhammad Marlina , Eriani Kartini , Fithri Aida , Rusdi Amalia , Saputra Hendra
Published: February 2020

The objective of this research was to investigate the effect of flamboyant flower extract as a natural antioxidant on sperm quality of Aceh cattle after dilution and equilibration. Fresh semen was collected from 2 healthy bull aged 3.5-4 years old. The research took place in BIB Laboratory. The method used was CRD (Completed Randomized Design), with 6 treatments and 5 replications each The treatments (m/v) were 0%, 0.05%, 0.10%, 0.15% and 0.20% of flamboyant flower extracts. The method used was CRD (Completed Randomized Design), with 6 treatments and 5 replications each. The treatments (m/v) were 0%, 0.05%, 0.10%, 0.15% and 0.20% of flamboyant flower extracts. The data obtained were analyzed by analysis of variance (ANOVA). Parameters evaluated in this study were motility, viability, plasma membrane integrity, and abnormality. Results showed that there was an insignificant effect (p>0.05) of flamboyant flower extract on the quality of Aceh cattle spermatozoa. The best percentage of motility and viability, 80.0% and 88.4%, respectively, were found at P3 (0.15% flamboyant flower extract). In can be concluded from the research that the addition of 0.15% (m/v)D. regiaflower extract was able to maintain sperm quality of Aceh cattle to be used in the artificial insemination program.
The Amino Acid Contents in Mangrove Rhizophora mucronata Leaves in Asahan, North Sumatra, Indonesia
Authors: Ningsih Sri S. , Ariyanto Dafit , Puspitasari Dian , Jayanegara Anuraga , Hamim Hamim , Gunawan Heru
Published: February 2020

Amino acids are important components of mangrove plant metabolisms. The aim of this study was to determine the relationship of mangrove R. mucronata leaf colors to the amino acid content. This study was conducted between March to August 2019. The leaves were taken 50 g. The assessment of Amino acids was conducted using UPLC Waters Acquity Class H with PDA Detector. The principal component analysis (PCA) was used to determine the relationship analysis between R. mucronata leaf colors and amino acid concentrations. The largest content was L glutamic acid with a green leaf content of 6139.57 ± 694.17 mg/kg and yellow leaf content of 6105.013 ± 113.2058 mg/kg. The results of PCA 1 showed that the influential amino acids were L-threonine (0.94), L-tyrosine (0.96), L-alanine (0.92), L-vanin (0.93), and PCA 2 showed glutamic acid (0.91). These results indicated that the difference in mangrove leaf colors affects the amino acid contents in the leaves.
Mechanisms of Dermatophyte Invasion on New Zealand Rabbit Skin Models
Authors: Jamin Faisal , Estuningsih Sri , Pribadi Eko S. , Handharyani Ekowati
Published: February 2020

Dermatophytosis is a dermatophyte fungi infection most commonly found in animals and humans. The first step of infection is started from the attachment of arthroconidium into stratum corneum. The attachment of fungi to the host cell is mediated by fungi adhesin and its interaction with the host receptor. The objective of this research was to develop the infection model of Microsporum gypseum and Microsporum canis by inoculating the macroconidia intradermally on the rabbit model. The macroconidia collection method from culture media was re-visualized as fungi ultrastructure using scanning electron microscopy (SEM). Skin lesion analysis was measured from clinical changes of the skin based on primary dermatophytosis signs such as circular alopecia with erythema and squamosal. Clinical confirmation test was done via skin sampling followed by histopathological examination using Methenamine Silver—Grocott’s (GMS) staining. As a result of this research, the in vivo infection model through direct infection of macroconidia applied intradermally was very effective in improving the direct infection to the invasion phase on the skin. This model confirmed the epidermal differentiation process and skin permeability showed primary lesion within 2 hours and aggravated up to 6 hours after inoculation. In conclusion, macroconidium is a potential source of infection to induce the dermatophytosis model and the severity of primary injection correlated with duration and the scale of clinical symptoms exhibited. This is a promising model for further research on the mechanism involved in dermatophyte infection.
Blood Profile and Reflex Righting in Central Pain Induced Rats after Administration of Sernai Leaf Extract (Wedelia biflora)
Authors: Rinidar Rinidar , Isa Muhammad , Hasan Muhammad , Armansyah Teuku , Zamzami Rumi S. , Ayuti Siti R.
Published: February 2020

Pain is a symptom of infection in the body but becomes crucial if it is not treated properly. Pain medication could be managed by administering anti-pain medications (analgesics). Currently, not all commercially available analgesic drugs can be used in animals, due to biochemical and metabolic variations between species causing difficulties in dosage determination and drug administration to the patient. This condition affects the drug efficacy which is incompatible with clinical relevance, has a narrow therapeutic index (NTS), and toxic. Wedelia biflora plants contain triterpenoid compounds that have received considerable attention from paramedics and pharmaceuticals, due to its ability as a therapeutic agent for chemopreventive, analgesic-antipyretic, anti-inflammatory and cancer. The purpose of this study was to obtain the basic ingredients of analgesic drugs. The 60 rats aged 3 months with bodyweight ranged 150-200 g were used in this study and divided into 2 experiments. In the first experiment, 30 rats were divided into 5 groups : K1 (control group) were given aquadest, the K2 was given 0.5 mg/ml meloxicam drug, the groups K3, K4, and K5 were given Wedelia biflora leaf extract with dose of 40 mg/kg BW, 50 mg/kg BW, and 60 mg/kg BW, respectively. The observation was carried out on pain response and blood profile of the rats. In the second experiment, the reflex righting of the rats in 5 group treatments were observed after administered with Wedelia biflora leaves extract at dose of 40, 50, 60, 120, and 240 mg/kg BW, respectively. Central pain test was carried out using tail emersion method and hot plate, while righting reflexes were observed starting from, 30, 60, 120, 240 and 360 minutes after giving sernai leaf extract. The results showed that the Wedelia biflora leaves have the ability as analgesic in the rat without altering the blood profile, and also poses a positive effect on reflex righting.
Nigerian Oil Palm Industry as a Sustainable Renewable Energy Resource
Authors: Ishola Felix , Towoju Olumide , Mamudu Angela , Olatunji Obafemi , Akinlabi Stephen , Oladejo Joana
Published: February 2020

Nigeria had been standing aloof at exploring her bioresources as a means of combatting her energy cum economic challenges. After some critical examination, the authors showcased Nigerian Palm Industry as a viable biofuel source yet unexplored. Using a combination of some economic and vegetation facts and figures to comparatively analyse, Nigerian oil palm industry to validate the prospect of a sustainable commercial-scale biofuel production that can serve as both affordable alternative cleaner energy fuel for her populace and immense export revenue. The Nigerian government is encouraged to latch onto this bioresource prospect.
Optimal hyperparameters for random forest to predict leakage current alarm on premises
Authors: Yokoyama Akihiro , Yamaguchi Nobuyuki
Published: February 2020

While the number of private electrical facilities is increasing, there are not enough security personnel to perform the security work. In this paper, we propose a random forest model for predicting leakage current alarms in order to improve the efficiency of electrical safety operations. A random forest was created using periodic inspection data, alarm data, and meteorological data as explanatory variables, and generalization performance was evaluated by OOB-based F-measure. In order to obtain the highest performance, a grid search was performed to optimize the hyperparameters. As a result, it was possible to achieve alarm prediction with a certain level of performance. In addition, the optimal hyperparameters were found by grid search, and the F-measure was improved.
Extrasolar planets: from dust to new worlds
Authors: Ercolano Barbara
Published: February 2020

Thousands of exoplanets have been discovered and the search for life outside Earth is at the forefront of astrophysical research. The planets we observe show a mind-blowing diversity that current theories strive to explain as part of the quest to assess the chances of finding life outside the Earth.
Development of a fish-based index for the assessment of the ecological status of Lake Balaton in the absence of present day reference condition
Authors: Specziár András , Erős Tibor
Published: February 2020

A fish-based index is proposed to indicate the ecological status of Lake Balaton, Hungary in accordance with the standard of the European Water Framework Directive (WFD). The Balaton fish index (BFI) synthetises information of 13 lake-specific fish metrics including gillnetting and electric fishing data of species richness of native assemblages, relative abundance, biomass and age structure of native key species, representation of non-native species and general health status. The main anthropogenic pressures considered were the degradation of littoral habitats, invasion of non-native fish species, eutrophication and fishing/angling including stocking. Ecological quality ratio (EQR) is assessed by relating actual fish assemblage metrics to the supposed undisturbed reference status of Lake Balaton reconstructed by expert judgement based on recent and historic information on the fish fauna and its changes. Values of BFI were consistent and indicated good ecological status of Lake Balaton in the period of 2005–2018. This study provides an example on how an EQR assessment methodology might be established in unique habitats with no possibilities for statistical evaluation of pressure-respond relationships and exact determination of the reference status.
Chemotaxis on networks: Analysis and numerical approximation
Authors: Egger Herbert , Schöbel-Kröhn Lukas
Published: February 2020

We consider the Keller–Segel model of chemotaxis on one-dimensional networks. Using a variational characterization of solutions, positivity preservation, conservation of mass, and energy estimates, we establish global existence of weak solutions and uniform bounds. This extends related results of Osaki and Yagi to the network context. We then analyze the discretization of the system by finite elements and an implicit time-stepping scheme. Mass lumping and upwinding are used to guarantee the positivity of the solutions on the discrete level. This allows us to deduce uniform bounds for the numerical approximations and to establish order optimal convergence of the discrete approximations to the continuous solution without artificial smoothness requirements. In addition, we prove convergence rates under reasonable assumptions. Some numerical tests are presented to illustrate the theoretical results.
Research on the relationship between the rail corrugation and the vibration response of the wheel-rail system
Authors: Jia Xinyu , Li Guoqing , Liu Xiubo , Chen Peng
Published: February 2020

Rail corrugation is a very common phenomenon in high-speed railways. Rail corrugation can cause increased vibration of trains and tracks, and may even affect the safety of train operation. Therefore, this paper will analyze the vibration of the wheel-rail system caused by the rail corrugation. The actual transient rolling contact model is established by using explicit and implicit finite element methods. Through the calculation of the wheel-rail contact force and the wheel-rail mode, the vibration relationship between the rail corrugation and the wheel-rail system is obtained. It can provide some references for further analysis of the cause of rail corrugation.
Khartoum sky trains network: a study on implementing caterpillar trains concept in Khartoum
Authors: Mohammed Mohammed A. , Mohammed Omer , Ibrahim Mohamed , Osman Huda G.
Published: February 2020

The experience of using public transportation in Khartoum is hectic due to over (1.5) Million seats in daily deficit. This research explores the daunting issues of public transport in developing countries like Sudan, taking Khartoum as a case study, and studies the possible alternatives to find an innovative solution that counters them. This paper reviewed the concept presented by MIT scholars in 2017 which was an innovative idea of elevated mini-trains that are intended to run over city streets called (Caterpillar Trains). The paper investigated the use of the C-Trains when integrated with LRT to form the Khartoum Sky Trains Network (STN). It was found that the STN is an optimum model for developing countries, as they were found able to meet the demands of public transport, in both short term and long term. The expected various environmental, social and economic impacts of such large infrastructure project were also studied. Finally, the research suggests that the Build-Operate-Transfer (BOT) contracting module can be utilized to overcome the construction costs, the concession period of which was found through a FORTRAN95 program.
Research on Liquefied Natural Gas(LNG) inland river transportation security risk assessment and security technology based on risk management
Authors: Yuchang Hu , Liansheng Xu
Published: February 2020

Using the Analytic Hierarchy Process and taking a certain section of the lower reaches of the Yangtze River as an example, this paper analyzed and identified the risk of inland river transportation of LNG, established the risk assessment criteria. According to the assessment results, it can be concluded that the current security risk situation of inland river LNG transportation is between "general" and "higher", and puts forward corresponding suggestions to improve security.
Study on the effectiveness of navigation safety measures for Nanjing Yangtze River Bridge
Authors: Zhao Feilong , Guo Guoping
Published: February 2020

Combined with navigation safety measures such as navigation mark adjustment, synchronous flash distribution, and real ship test adopted by Nanjing Yangtze River Bridge, theoretical analysis methods and data analysis are used to determine the safety evaluation risk index system, and an unascertained measure evaluation model based on entropy weight is constructed. Through the comparison of the effectiveness of the security measures analyzed by the questionnaire, the effectiveness of the bridge safety guarantee measures was evaluated; further suggestions on the optimization of relevant safety protection measures were proposed. The research results are of great significance for maintaining the safety of the bridge, the navigation order of the waters in the bridge area, protecting the navigation resources of the bridge area, and ensuring the navigation safety of the ship.
An Optimization Model of Railway Empty Container Allocation Based on Customer Satisfaction
Authors: Zhang Zhiwei , Li Xiaohong
Published: February 2020

With the rapid development of modern corporate management, customer satisfaction evaluation has been applied to the management of many companies. Railway empty container allocation not only involves the cost of the railway transportation, but also considers the customer's requirements for time and convenience, etc. Therefore customer satisfaction evaluation also becomes very important for railway container allocation decision. However, it is not easy to properly quantify customer satisfaction, because there are many indicators that cannot be directly quantified. This paper proposes a customer satisfaction evaluation index system based on the RATER index, and adopts a comprehensive evaluation method to achieve quantitative evaluation of customer satisfaction. An empty container allocation optimization model based on customer satisfaction is established. The model can comprehensively consider the interests of both the railway and customers, and provide an effective reference for the railway transportation department to improve the transportation service and optimize empty container allocation plan.
Freighter Loading Efficiency at Airports for International Air Express
Authors: Lu Hua-An , Chung Chi-Sheng
Published: February 2020

Loading efficiency of freighters plays an indispensable role for the service performance of international air express companies. This study examined the priorities of factors to affect freighter loading efficiency at Taoyuan International airport (TPE) with an analytic hierarchy process (AHP). Unit load device (ULD) inventory control, load factor and load plan were ranked top 3 from 15 factors by practical experts. This study used the technique for order preference by similarity to ideal solution (TOPSIS) to evaluate 26 flights of MD11 freighters operated by an international air express company at TPE. The results revealed that the performance ranges between the best and worst flights were obvious.