Miracle-dz/UniFAR-FTUs huggingface dataset:
Nitrogen fertilizer leaching in an Oxisol cultivated with sugarcane

A lixiviacao de nitrogenio (N) abaixo da zona radicular representa uma valiosa perda do nutriente para as plantas e uma fonte potencial de poluicao do lencol freatico. Quantificaram-se as perdas de N por lixiviacao num Latossolo Vermelho Amarelo cultivado com cana-de-acucar (Saccharum officinarum) durante o ciclo agricola de cana-planta. A cultura foi implantada e fertilizada no sulco com 120 kg ha-1 de N-ureia. Para conhecer o destino do fertilizante, foram instaladas quatro microparcelas onde o fertilizante era marcado com o isotopo 15N. As entradas e saidas de N a 0,9 m de profundidade foram quantificadas diariamente pela densidade de fluxo de agua e a concentracao de N da solucao no solo. No periodo de avaliacao, a precipitacao pluvial foi 141 mm menor que a media historica (1.315 mm) sendo janeiro mais seco que o normal. A concentracao de N mineral media foi 1,8 mg L-1. A abundância de 15N foi superior a abundância natural do isotopo, especialmente no inicio do periodo de avaliacao, permanecendo logo constante (0,453% de 15N). A drenagem interna foi de 91 mm de agua e a perda por lixiviacao foi 1,1 kg ha-1 de N com apenas 54 g ha-1 derivados do fertilizante. Portanto, com elevada demanda de nutrientes e elevada incorporacao de restos culturais, nao foram registradas perdas apreciaveis de N por lixiviacao devido ao fato de o excedente de agua entre os meses de dezembro e marco ter sido menor que o esperado e pela elevada extracao de N pela cana-de-acucar.
Generating porosity during olivine carbonation via dissolution channels and expansion cracks

Abstract. The olivine carbonation reaction, in which carbon dioxide is chemically incorporated to form carbonate, is central to the emerging carbon sequestration method using ultramafic rocks. The rate of this retrograde metamorphic reaction is controlled, in part, by the available reactive surface area: as the solid volume increases during carbonation, the feasibility of this method ultimately depends on the maintenance of porosity and the creation of new reactive surfaces. We conducted in situ dynamic X-ray microtomography and nanotomography experiments to image and quantify the porosity generation during olivine carbonation. We designed a sample setup that included a thick-walled cup (made of porous olivine aggregates with a mean grain size of either ∼ 5 or ∼ 80 µm) filled with loose olivine sands with grain sizes of 100–500 µm. The whole sample assembly was reacted with a NaHCO3 aqueous solution at 200 °C, under a constant confining pressure of 13 MPa and a pore pressure of 10 MPa. Using synchrotron-based X-ray microtomography, the three-dimensional (3-D) pore structure evolution of the carbonating olivine cup was documented until the olivine aggregates became disintegrated. The dynamic microtomography data show a volume reduction in olivine at the beginning of the reaction, indicating a vigorous dissolution process consistent with the disequilibrium reaction kinetics. In the olivine cup with a grain size of ∼ 80 µm (coarse-grained cup), dissolution planes developed within 30 h, before any precipitation was observed. In the experiment with the olivine cup of ∼ 5 µm mean grain size (fine-grained cup), idiomorphic magnesite crystals were observed on the surface of the olivine sands. The magnesite shows a near-constant growth throughout the experiment, suggesting that the reaction is self-sustained. Large fractures were generated as the reaction proceeded and eventually disintegrated the aggregate after 140 h. Detailed analysis show that these are expansion cracks caused by the volume mismatch in the cup walls, between the expanding interior and the near-surface which keeps a nearly constant volume. Nanotomography images of the reacted olivine cup reveal pervasive etch pits and wormholes in the olivine grains. We interpret this perforation of the solids to provide continuous fluid access, which is likely key to the complete carbonation observed in nature. Reactions proceeding through the formation of nano- to micron-scale dissolution channels provide a viable microscale mechanism in carbon sequestration practices. For the natural peridotite carbonation, a coupled mechanism of dissolution and reaction-induced fracturing should account for the observed self-sustainability of the reaction.
Working memory capacity, content familiarity, and university EFL students’ reading comprehension

This study explores the effect of working memory capacity (WMC) and content familiarity (CF) on EFL reading comprehension. Seventy senior students from a private university in Malang, Indonesia, were involved in the study, having been selected based on their English proficiency of at least pre-advanced level. These students were required to complete a reading span test for the WMC and a multiple-choice reading test based on CF. The findings of this study show that there is no interaction effect between WMC as the main independent variable and CF as the moderator variable; this implies that the students with higher WMC comprehend texts better than those with lower WMC, regardless of whether they are familiar or not with the texts.
Unorganized Enterprises and Rural-Urban Migration in India: The Case of the Cycle Rickshaw Sector in Delhi

In 2010/11, we conducted a survey of cycle rickshaw pullers and rickshaw owners located throughout Delhi, India. We drew a sample of 132 rickshaw owners (called Thekedars) and a representative sample of 1,320 rickshaw pullers. The survey results show that most rickshaw pullers in Delhi are short-term, temporary migrants. Most rickshaw pullers are poorly educated. The majority migrated from villages in the states of Bihar and Uttar Pradesh. Social networks that extend from places of origin to final destinations facilitate migration. More than 90% of rickshaw pullers operate rental rickshaws owned by Thekedars. Rickshaw pulling involves hard physical labor. On average, a rickshaw puller works 11 hours per day, over 27 days per month. We estimate the average daily earning to be Rs. 260. A typical migrant rickshaw puller may save more than Rs. 2,000 per month. He may send these funds to his village home. This is the migrant rickshaw pullers’ contribution to rural poverty reduction. Thekedars provide the fulcrum upon which the whole cycle rickshaw transportation system of Delhi turns. , In addition to the rental of cycle rickshaws to migrant rickshaw pullers, Thekedars manage the administrative and legal aspects of their rickshaw rental business throughout the year. Their occupational history shows that many of them became a Thekedar from low beginnings, including rickshaw pulling and rickshaw repair jobs. On average, a Thekedar owns 56 rickshaws, approximately two-thirds of which are rented on a daily basis. Pullers pay a fixed rental fee per day at an average rate of Rs. 34. Net of business expenditures, monthly rickshaw rental income per Thekedar is estimated at approximately Rs. 5,600 for small and medium Thekedars and Rs. 41,000 for large Thekedars. The internal rate of return on investment over 5-6 years of the working life of a rickshaw is estimated to range between 18% and 62% per year. Currently, the rules and regulations on t he cycle rickshaw sector in Delhi are based on the principal of the one-rickshaw, one-owner, one-driver, one-license policy. However, this policy does not reflect the real-life situations we encountered in our survey. We recommend that Thekedars be endowed with legal entity status. This would result in the healthy development of urban transport in Delhi.
Physical and Mechanical Properties of Porcelain Formed by Substituting Quartz with HCl Treated Palm Oil Fuel Ash

Palm Oil Fuel Ash (POFA), is a waste material from palm oil industries that has potential of recycling in the porcelain production due to its high content of silica. POFA is produced by burning palm oil shells, empty fruit branches and fibers as a fuel to heat up the boiler for electricity generation in the industries. This research is aimed at producing porcelain with the substitution of treated POFA with quartz at 20 wt%. Treated POFA was dried in an oven for 24 hours at 110°C and ground using ball mill machine for 12 hours to get particle size ˂50µm. 20 wt% of POFA powder was substituted for quartz and mixed with the composition of porcelain for 12 hours and then pressed into pellets at a mold pressure of 91 MPa. The pellets were sintered at a temperature of 1200°C for 2 hours soaking time at a heating rate of 5°C per minute. It was revealed that the maximum density was achieved at 2.38g/cm3 as the molarity of HCl is increased to 3 mole with the counterpart hardness of 7826 MPa. This improvement may be attributed to the increased in the silica content as a result of treatment of POFA with HCl acid.
Characterization of Thiothrix nivea

Two strains of Thiothrix nivea were examined to determine their morphological and physiological features. Microculture studies revealed the production of gliding gonidia and possible mechanisms for rosette formation. The strains were able to use only 4 of 41 carbon sources tested, but only if sulfide or thiosulfate was present. Physiologically, Thiothrix may be an obligate mixotroph. The guanine-plus-cytosine content of the deoxyribonucleic acid was 52 mol%. Our strains fit the description of T. nivea, and strain JP2 (= ATCC 31500) was designated as the neotype strain.
Features of Urban Food and Nutrition Security and Considerations for Successful Urban Programming

In this paper we discuss the wide disparities that exist in childhood malnutrition, food insecurity and livelihoods within urban areas which, when combined with the mobility of urban residents, add to the complexity of designing, targeting and implementing urban programmes. Livelihood security in urban areas is dependent on cash income, especially for food expenditures, and hence employment. For women, employment brings about the need for support with childcare; we analyse a programme that provides the double benefit of delivering affordable and reliable childcare for extended hours, and allowing women to secure a more formal employment and obtaining employment benefits. Other factors that need to be considered in shaping urban programmes include land and housing security, the crime and violence situation, the availability and nature of social networks, and governance issues. Finally, we discuss potential strategic responses to the challenges of urban programming.
Development of a Scale on e-Consumers' Attitudes towards Ethically Questionable Online Behaviors*

The purpose of this study is to develop a valid and reliable scale to measure e-consumers’ attitudes towards ethically questionable online behaviors (e-CEQOB). A scale measuring e-consumers’ attitudes towards such behaviors was developed using the conventional steps of scale development of Churchill (1979). The generated items were reduced to 24 items following EFA. The psychometric properties of e-CEQOB were assessed on two independent non-student samples in Istanbul, Turkey (Sample 1, N=635, and Sample 2, N=880 – randomly split into two (G1, n=438, G2, n=442)). The e-CEQOB scale was statistically confirmed and validated using CFA and Maximum Likelihood Estimation (Lisrel 8.72). As a result of EFA and CFA, a 24-item, five-factor multi-dimensional construct on e-CEQOB was developed and its reliability and validity were tested and confirmed. Taking into consideration the gap in the literature, this study has developed and validated an instrument that measures e-consumers’ attitudes towards ethically questionable online behaviors. Although there are a limited number of studies on such, none has attempted to develop a scale using the conventional steps of scale development and none has been tested for validity and reliability, nor has any been widely accepted. This study fills this gap and presents a reliable and valid scale to measure the attitudes of e-consumers towards ethically questionable online behaviors (e-CEQOB). The creation of e-CEQOB serves as an opportunity for researchers studying in this rapidly developing medium to extend their research to critical ethical issues. The application
Do giant molecular clouds care about the galactic structure

We investigate the impact of galactic environment on the properties of simulated giant molecular clouds formed in a M83-type barred spiral galaxy. Our simulation uses a rotating stellar potential to create the grand design features and resolves down to 1.5 pc. From the comparison of clouds found in the bar, spiral and disc regions, we find that the typical GMC is environment independent, with a mass of 5e+5 Msun and radius 11 pc. However, the fraction of clouds in the property distribution tails varies between regions, with larger, more massive clouds with a higher velocity dispersion being found in greatest proportions in the bar, spiral and then disc. The bar clouds also show a bimodality that is not reflected in the spiral and disc clouds except in the surface density, where all three regions show two distinct peaks. We identify these features as being due to the relative proportion of three cloud types, classified via the mass-radius scaling relation, which we label A, B and C. Type A clouds have the typical values listed above and form the largest fraction in each region. Type B clouds are massive giant molecular associations while Type C clouds are unbound, transient clouds that form in dense filaments and tidal tails. The fraction of each clouds type depends on the cloud-cloud interactions, which cause mergers to build up the GMA Type Bs and tidal features in which the Type C clouds are formed. The number of cloud interactions is greatest in the bar, followed by the spiral, causing a higher fraction of both cloud types compared to the disc. While the cloud types also exist in lower resolution simulations, their identification becomes more challenging as they are not well separated populations on the mass-radius relation or distribution plots. Finally, we compare the results for three star formation models to estimate the star formation rate and efficiency in each region.
Conceptualisation of Misunderstanding and Understanding – a phenomenographic study of students’ conceptions of allocative efficiency in Economics

It is not uncommon for lecturer to assume student understanding key concepts in her/his organisation and presentation of a topic, when these concepts, in fact, can be quite problematic for the students. This creates barriers to knowledge development in students. To overcome this barrier, it is important that we obtain students’ knowledge prior to and following instructions to inform teaching. A number of studies (Voss et al, 1986, Pong, 1999, Marton, 1988) have found that the student might have learnt a concept and utilised it in one context, but were not capable of transferring it for use in another, most notably in the context of everyday life. This raises two related questions: (1) When a student is taught an economic concept but chooses not to use it to make sense of an economic phenomenon, what is it about the economic concept that they have learnt (or mis-learnt)? (2) If the student possesses misunderstanding, how is it acquired? The paper reports on the preliminary findings of a study conducted at an Australian university, exploring the various ways commencing economics students understand the concept of allocative efficiency. In this study, written responses taken from 90 exam scripts to a structured final exam question are subject to rigorous phenomenographic analysis (Marton, 1981). Six conceptions of allocative efficiency are identified, and insights into these qualitatively different, commonly shared perceptions of this fundamental economic concept, which emerge from students’ written responses, allow us to better understand how they develop various misconceptions. The paper also discusses the implications of these findings and argues for a relational perspective of effective teaching.
Multi-response robust design by principal component analysis

Abstract Most previous Taguchi method applications have only addressed a single-response problem. However, more than one correlated response normally occurs in a manufactured product. The multi-response problem has received only limited attention. In this work, we propose an effective procedure on the basis of principal component analysis (PCA) to optimize the multi-response problems in the Taguchi method. With the PCA, a set of original responses can be transformed into a set of uncorrelated components. Therefore, the conflict for determining the optimal settings of the design parameters for the multi-response problems can be reduced. Two case studies are evaluated, indicating that the proposed procedure yields a satisfactory result.
How Can We Boost Competition in the Services Sector

This paper uses the 2004 amendment to the German Trade and Crafts Code as a natural experiment for assessing the causal effects of this reform on the probabilities of being self-employed and of transition into and out of self-employment. This is achieved by using repeated cross-sections (2002–2009) of German microcensus data. I apply the difference-in-differ‐ ences technique for three groups of craftsmen which were subject to dif‐ ferent intensities of treatment. The results show that the complete exemp‐ tion from the educational entry requirement has fostered self-employment significantly by substantially increasing the entry probabilities, while exit rates have remained unaffected. I find similar, though weaker relative ef‐ fects for the treatment groups that were subject to a reduction of entry costs or a partial exemption from the entry requirements. Moreover, I con‐ sider effect heterogeneity within each of the treatment groups with respect to gender and vocational training, and show that the deregulation of entry requirements has been most effective for untrained workers.
Grammatical and pragmatic properties of the DP in children with Specific Language Impairment (SLI) and in children with High Functioning Autism (HFA)

This study investigates whether grammar and pragmatics are separate linguistic components or not, and whether children with SLI and children with HFA have overlapping or distinct linguistic profiles. We examine two DP-related phenomena: the mass-count distinction (grammatical) and the choice for a definite/indefinite article (pragmatic). We tested 27 children with HFA aged 6–14, age and gender matched to 27 children with SLI, and 27 TD controls on a Quantity Judgment Task (mass-count) and an Elicited Production Task (article choice). Our results show that pragmatics can be impaired independently from grammar (in HFA) and vice versa (in SLI), providing evidence for a modular view of grammar and pragmatics, and against an overlap in the profiles of SLI and HFA.
Effect of rapeseed meal on nutrient digestibility and gut morphology in broiler chickens.

The study was carried out to determine the effect of rapeseed meal (RSM) on nutrient digestibility and intestinal parameters of jejunum of 21 days old broiler chickens. Three groups of Ross 308 chickens were formed and fed with corn-soy based feed (control group) or feed with inclusion of 10% or 15% of rapeseed meal (low glucosinolate and low eruca acid content). All mixtures were balanced to the same energy and crude protein level. To determine digestibility, 20 male chickens per treatment were put into metabolic cages. Digestibility was determined by using the method of total collection. Digestibility of dry matter, organic matter, crude protein, fat and energy was determined. At 21 days of age, chickens were sacrificed to obtain samples for morphometric parameters of jejunum. On jejunal samples, villus height and area, crypt depth and villus to crypt ratio were measured as indicators of gut integrity. No significant differences (P>0.05) were observed in any measured digestibility or gut health parameter. Addition of up to 15% of rapeseed meal in well balanced diets of young broiler chicken does not have an adverse effect on both digestibility of nutrients and broiler gut health.
An Improved Iterative Procedure for Outlier Detection in Time Series

We address some potential problems with the existing procedures of outlier detection in time series. Also we propose modifications in estimating model parameters and outlier effects in order to reduce the number of tests and to increase the detection accuracy. Experiments with some artificial data sets show that the proposed procedure significantly reduces the number of tests and enhances the accuracy of estimated parameters as well as the detection power.
Estimating aboveground woody biomass change in Kalahari woodland: combining field, radar, and optical data sets

ABSTRACT Maps that accurately quantify aboveground vegetation biomass (AGB) are essential for ecosystem monitoring and conservation. Throughout Namibia, four vegetation change processes are widespread, namely, deforestation, woodland degradation, the encroachment of the herbaceous and grassy layers by woody strata (woody thickening), and woodland regrowth. All of these vegetation change processes affect a range of key ecosystem services, yet their spatial and temporal dynamics and contributions to AGB change remain poorly understood. This study quantifies AGB associated with the different vegetation change processes over an 8-year period, for a region of Kalahari woodland savannah in northern Namibia. Using data from 101 forest inventory plots collected during two field campaigns (2014–2015), we model AGB as a function of the Advanced Land Observing Satellite Phased Array L-band synthetic aperture radar (PALSAR and PALSAR-2) and dry season Landsat vegetation index composites, for two periods (2007 and 2015). Differences in AGB between 2007 and 2015 were assessed and validated using independent data, and changes in AGB for the main vegetation processes are quantified for the whole study area (75,501 km2). We find that woodland degradation and woody thickening contributed a change in AGB of −14.3 and 2.5 Tg over 14% and 3.5% of the study area, respectively. Deforestation and regrowth contributed a smaller portion of AGB change, i.e. −1.9 and 0.2 Tg over 1.3% and 0.2% of the study area, respectively.
Early Adolescent Depression Symptoms and School Dropout: Mediating Processes Involving Self-Reported Academic Competence and Achievement

Research on adolescent well-being has shown that students with depression have an increased risk of facing academic failure, yet few studies have looked at the implications of adolescent depression in the process of school dropout. This study examined mediation processes linking depression symptoms, self-perceived academic competence, and self-reported achievement in 7th grade to dropping out of school in later adolescence. We followed 493 (228 girls and 265 boys) French-speaking adolescents from low-socioeconomic-status secondary schools in Montreal (Quebec, Canada) for 6 years. Almost 34% of participants dropped out of school during this period. Findings indicated that self-reported depression symptoms in 7th grade increased the risk of dropping out of school in later adolescence. Structural equation modeling revealed that the predictive relationship between depression symptoms and school dropout was mediated by self-perceptions of academic competence. Current findings provide support for self-perceptions of competence as mediational processes in the relationship between adolescent depression symptoms and early school leaving.