Miracle-dz/UniFAR-FTUs huggingface dataset:
Stable photon orbits in stationary axisymmetric electrovacuum spacetimes

We investigate the existence and phenomenology of stable photon orbits (SPOs) in stationary axisymmetric electrovacuum spacetimes in four dimensions. First, we review the classification of equatorial circular photon orbits on Kerr-Newman spacetimes in the charge-spin plane. Second, using a Hamiltonian formulation, we show that Reissner-Nordstr\"om diholes (a family encompassing the Majumdar-Papapetrou and Weyl-Bach special cases) admit SPOs, in a certain parameter regime that we investigate. Third, we explore the transition from order to chaos for typical SPOs bounded within a toroidal region around a dihole, via a selection of Poincar\'e sections. Finally, for general axisymmetric stationary spacetimes, we show that the Einstein-Maxwell field equations allow for the existence of SPOs in electro vacuum, but not in pure vacuum.
Size and Stability of Curcumin Niosomes from Combinations of Tween 80 and Span 80

The ratios of Tween 80 to Span 80 are important in controlling the physicochemical characteristics of curcumin niosomes. Thus, in this study the correlations of combination of Tween 80 and Span 80 at different ratios with the size and stability of curcumin niosomes were investigated. Initially curcumin was dissolved in chloroform and methanol (v/v= 3:1), followed by the preparation of niosomes by thin-film hydration method with the mole ratio of mixture of Tween 80 and Span 80 to cholesterol of 2:1. The ratios of Tween 80 to Span 80 in the mixture were set at 1:1, 1:9, 9:1, 2:3 and 3:2 with Hydrophilic-Lipophilic Balance (HLB) values of 9.65, 5.37, 13.93, 8.58 and 10.72, respectively. As expected, niosome barely formed at HLB value 13.93. This might be due to the molecule being hydrophilic and well hydrated which inhibits the formation of a stable bilayer in solution. It was found that the formulation which has higher Span 80 and lower HLB value leads to larger niosome before sonication. The largest niosome size achieved from Tween 80 to Span 80 ratio of 1:9 and 2:3 was 77.36 and 59.85 μm, respectively. On the other hand, for the ratio of 3:2, the largest niosome formed before sonication was less than 50.00 μm. After sonication, the niosome size reduced to less than 35.00 μm for all formulations. It was showed that formulation with Tween 80 to Span 80 ratio of 1:9 has superior curcumin entrapment efficiency and best stability during storage. The results demonstrated that appropriate ratio of Tween 80 to Span 80 was necessary for forming small and stable curcumin niosomes.
A recursive construction of joint eigenfunctions for the hyperbolic nonrelativistic Calogero-Moser Hamiltonians

We obtain symmetric joint eigenfunctions for the commuting PDOs associated to the hyperbolic Calogero-Moser N-particle system. The eigenfunctions are constructed via a recursion scheme, which leads to representations by multidimensional integrals whose integrands are elementary functions. We also tie in these eigenfunctions with the Heckman-Opdam hypergeometric function for the root system A_{N-1}.
Assessment of mathematics assessment: Discrepancies between standardised testing and teacher judgements in an Australian primary school context

Withmoves afoot to review Australia's National Curriculum, perhaps it is timely toassess teacher assessment practices. This study compares the judgments thatteachers make on their students' mathematics achievement with results takenfrom Australia's National Assessment Program: Literacy and Numeracy (NAPLAN). Usinga sample of 2144 students, drawn from the Longitudinal Study of AustralianChildren (LSAC), the study develops two regression models: one with teacherratings of achievement as the outcome variable, and the other with NAPLANnumeracy results as the outcome. A number of individual and environmentalfactors are then regressed onto these outcome variables, and the magnitudes oftheir effects are compared. The results indicate a consistency between the twoassessment approaches, except for the assessment of students with specialneeds, where teachers significantly under-estimate the mathematical abilitiesof these students. Implications of these results are discussed.
How Disgust Enhances the Effectiveness of Fear Appeals

The current research explores the role of disgust in enhancing compliance with fear appeals. Despite its frequent use in advertising and prevalence in consumer settings, little is known about the specific role that disgust plays in persuasion. This article explores the unique characteristics of disgust and examines its distinctive effect on persuasion. The results across a series of four studies demonstrate that adding disgust to a fear appeal appreciably enhances message persuasion and compliance beyond that of appeals that elicit only fear. Importantly, the results trace the persuasive effects of disgust to its strong and immediate avoidance reaction.
Economic costs and returns from organic farming in Oyo state, Nigeria.

The study evaluated the costs and returns of organic farming using the farmers in Akinyele Local Government of Oyo state, Nigeria as case study. An interview schedule was administered to the respondents to elicit useful information. The analysis was based on input and output data collected from one hundred and eighty farmers selected at random from the area from which eighty-eight used organic farming, fifty-eight used non-organic farming and thirty-four used both farming systems. The data were analysed using descriptive statistics, Duncan Multiple Range Test (DMRT), t-test group statistics and gross margin analysis. Results of the analysis indicated that 57.8% of the respondents were male, 66.1% were married and all the respondents had formal education either at primary, secondary or tertiary level. Furthermore, 48.9% of the respondents adopted organic farming system, 32.2% adopted non-organic farming system while 18.9% adopted both organic and non-organic farming systems. From the gross margin analysis done, both organic and non-organic farming are profitable. However, it is more profitable to produce vegetable and maize organically. Costs related to fertiliser and the post-harvest preservation and sales was higher in non-organic farming, whereas the cost of crude farm implements and labour was higher in organic farming. There should be an intensified awareness to improve the level of participation of farmers in organic farming, recommendation of organic products to people, and government policies that encourage farmers to go into organic farming, especially by making their products readily disposable in already prepared market at encouraging prices.
Investigating the driver’s response time at signalized intersections

It is generally accepted that, behavioural variables may show differences in different countries, and sometimes in different regions depending on cultural and other socio-economic factors. In literature, several researchers have emphasized that performance of signalized intersections is highly related with drivers’ behaviour. However, only a few parameters can be used to reflect drivers’ behaviour in performance analysis. Start response time is used as a key parameter in calibration of analytical and simulation models. In this study, a detailed analysis is conducted on the variability of start response time with respect to parameters like those that manoeuvre type, cycle time, gender of drivers’, etc. by using data obtained from signalized intersections in Izmir, Turkey. Analysis showed that left and right turning drivers have slightly shorter start response times than all through passing vehicles. In addition, the effect of start response time on base saturation flow is discussed.
Late Oligocene obliquity-paced contourite sedimentation in the Wilkes Land margin of East Antarctica: implications for paleoceanographic and ice sheet configurations

The late Oligocene experienced atmospheric concentrations of CO 2 between 400 and 750 ppm, which are within the IPCC projections for this century, assuming unabated CO 2 emissions. However, Antarctic ice sheet and Southern Ocean paleoceanographic configurations during the late Oligocene are not well resolved, but are important to understand the influence of high-latitude Southern Hemisphere feedbacks on global climate under such CO 2 scenarios. Here, we present late Oligocene (26–25 Ma) ice sheet and paleoceanographic reconstructions recorded in sediments recovered by IODP Site U1356, offshore of the Wilkes Land margin in East Antarctica. Our study, based on a combination of sediment facies analysis, physical properties, and geochemical parameters, shows that glacial and interglacial sediments are continuously reworked by bottom-currents, with maximum velocities occurring during the interglacial periods. Glacial sediments record poorly ventilated, low-oxygenation bottom water conditions, interpreted to represent a northward shift of westerly winds and surface oceanic fronts. During interglacial times, more oxygenated and ventilated conditions prevailed, which suggests enhanced mixing of the water masses with enhanced current velocities. Micritic limestone intervals within some of the interglacial facies represent warmer paleoclimatic conditions when less corrosive warmer northern component water (e.g. North Atlantic sourced deep water) had a greater influence on the site. The lack of iceberg rafted debris (IRD) throughout the studied interval contrasts with early Oligocene and post-Oligocene sections from Site U1356 and with late Oligocene strata from the Ross Sea (CRP and DSDP 270), which contain IRD and evidence for coastal sea ice and glaciers. These observations, supported by elevated paleotemperatures and the absence of sea-ice, suggest that between 26 and 25 Ma reduced glaciers or ice caps occupied the terrestrial lowlands of the Wilkes Land margin. Unlike today, the continental shelf was not over-deepened, and thus marine-based ice sheet expansion was likely limited to coastal regions. Combined, these data suggest that ice sheets in the Wilkes Subglacial Basin were largely land-based, and therefore retreated as a consequence of surface melt during late Oligocene, rather than direct ocean forcing and marine ice sheet instability processes as it did in younger past warm intervals. Spectral analysis on late Oligocene sediments from the eastern Wilkes Land margin show that the glacial-interglacial cyclicity and resulting displacements of the Southern Ocean frontal systems between 26–25 Ma were forced by obliquity.
Side Effects of Immunities: the African Slave Trade

The resistance of Sub-Saharan Africans to diseases that were plaguing the southern United States contributed to the establishment of African slavery in those regions. Specifically, Africans' resistance to malaria increased the profitability of employing African slave labor, especially that of slaves coming from the most malaria-ridden parts of Africa. In this paper, I first document that African slavery was largely concentrated in the malaria-infested areas of the United States. Moreover, I show that the introduction of a virulent strain of malaria into US colonies greatly increased the share of African slaves, but only in states where malaria could thrive. Finally, by looking at the historical prices of African slaves, I show that enslaved individuals born in the most malaria-ridden African regions commanded higher prices.
Diffusion of Innovation and the Technology Adoption Curve: Where Are We? The Zimbabwean Experience

The introduction of the Internet has led to the development of new technologies and applications that have been adopted by organisations and their users to enable them to survive in this age of technology. Online technologies have penetrated Zimbabwe, particularly in the retail industry, however, little research has been done to link the research results to theory particularly the technology adoption theories. Therefore the objective of this study was to explore the current extent of adoption of online transaction platforms in the retail industry in Zimbabwe. Furthermore, this paper purposed to determine the extent of this adoption on the Technology Adoption Curve. The online transaction platforms studied were Internet banking, Automated Teller Machines, Mobile banking, Point of Sale and Mobile money. The study took a mixed method approach where both qualitative and quantitative strategies were used. A three-sample dataset comprising of 268 bank and supermarket customers, 56 bank managers and 31 supermarket managers was used. The resultant adoption rates were plotted on Moore’s Technology Adoption Curve. The results indicated that although the retail industry had made great strides to adopt online technology platforms, but the adoption by customers was relatively low at a market penetration of 14.5%. The study thus concluded that Zimbabwe’s online technologies were in their infancy stage on the maturity model adoption curve and were inside Moore’s chasm on the technology adoption curve. The study recommended to customers to use the adopted online technologies in order to keep abreast with the digital era. On the other hand, banks and supermarkets were urged to devise marketing strategies in an effort to cross the chasm in the Technology Adoption Curve.
Gametogenic Cycle and the Size at 50% of Group Sexual Maturity in Male Chlamys (Azumapecten) farreri nipponensis (Kuroda, 1932) (Bivalvia: Pectinidae) in Western Korea

We investigated the gametogenic cycle and spawning seasons of the male Chlamys (Azumapecten) farreri nipponensis by qualitative and quantitative analyses, and also the size at 50% of group sexual maturity was calculated by the data of first sexual maturity. In this study, the male gametogenic cycle of this species by qualitative analysis was divided into five successive stages: early active stage (January to March), late active stage (March to April), ripe stage (April to August), partially spawned stage (July to September), and spent/inactive stage (August to January). The male gametogenic cycle showed similar patterns with monthly changes in the gonadosomatic index and condition index. Particularly, spawning in male scallop occurred once a year from July to September, unlike the spawning period of this species (from June to August) reported by the previous researchers. In quantitative statistical analysis using an image analyzer system, the patterns of monthly changes in the percent (%) of the areas occupied by spermatogenic stages to the testis areas in males showed a maximum in June, and then sharply dropped from July to September, 2006. From these data, it is apparent that the spawning season of C. (A.) farreri nipponensis occurred once per year from July to early September, indicating a unimodal gametogenic cycle during the year. Shell heights at 50% of group sexual maturity (RM 50 ) fitted to an exponential equation were estimated to be 49.90 mm in males (considered to be one year old), and it was 100% for male scallops over 61.0 mm (considered to be two years old).
Developmental mode in benthic opisthobranch molluscs from the northeast Pacific Ocean: feeding in a sea of plenty

Mode of development was determined for 130 of the nearly 250 species of shallow-water, benthic opisthobranchs known from the northeast Pacific Ocean. Excluding four introduced or cryptogenic species, 91% of the species have planktotrophic development, 5% have lecithotrophic development, and 5% have direct development. Of the 12 native species with non-feeding (i.e., lecithotrophic or direct) modes of development, 5 occur largely or entirely south of Point Conception, California, where surface waters are warmer, lower in nutrients, and less productive than those to the north; 4 are known from habitats, mainly estuaries, that are small and sparsely distributed along the Pacific coast of North America; and 1 is Arctic and circumboreal in distribution. The nudibranchs Doto amyra Marcus, 1961 and Phidiana hiltoni (O'Donoghue, 1927) were the only species with non-feeding development that were widespread along the outer coast. This pattern of distribution of developmental mode is consistent with the prediction t.
Duration of overgrowth affects survival of encrusting coralline algae

Encrusting algae can withstand being overgrown for relatively long periods of time. Knowledge of the mechanisms operating to reduce loss of biomass and of the temporal scales over which these are efficient is crucial for understanding competitive interactions occurring via over- growth. In some red encrusting algae, the translocation of metabolites from unshaded to shaded parts of the thallus has been indicated as a possible mechanism for their resistance to overgrowth. This study tested the hypothesis that the efficacy of the connection between shaded and unshaded por- tions of the thallus in promoting the survival of the encrusting coralline alga Neogoniolithon brassica- florida, when overgrown, would vary according to the duration of the overgrowth. This hypothesis was tested experimentally by manipulating the availability of light and the connection between shaded and unshaded parts of the thalli. Although there was a slightly different response between experimental trials, the connection with unshaded parts enhanced the survival of shaded parts of the thallus, over a period of about 3 mo. In contrast, 8 mo after the start of the experiment, the percent- age cover of living N. brassica-florida under artificial shading devices was small, irrespective of the presence or absence of a connection with unshaded parts of the thallus. These results support the model that translocation of nutrients across the thallus could enable encrusting algae to survive being overgrown, but not indefinitely. This study underpins the need to take into account life-history traits of interacting species when interpreting competition occurring via overgrowth.
Error measures based on winner-takes-all and the performance of multilayer perceptron classifier

The squared error is a measure commonly employed for training neural networks. Alternative objective functions, directed for classification tasks, may be relevant for training neural networks classifiers. The present paper discusses why some types of objective function, used in training neural networks for classification, have shown better performance compared to the usual mean squared error (MSE). The study deals with the concept of winner-takes-all (WTA). For the condition of a trained network, it is demonstrated through a variance inequality that the application of the smooth WTA criterion (softmax) in the output estimates made by a multilayer perceptron (MLP) classifier tends to reduce the variance of such estimates. However, as the softmax approximates the abrupt WTA criterion, there is no variance reduction due to such inequality. On the other hand, considering a network to be trained, error measures based on the composition of MSE with WTA are defined to serve as objective function of particle swarm optimizer in training a MLP for solving logic gates classification. Experimental results point out that the steeper is the WTA criterion, the faster is reaching a solution for the AND gate, moreover, the functions depending on a steeper WTA were superior to the simple MSE. Curiously, in the case of XOR problem, the solution was more often reached when using the pure MSE, whereas most objective functions based on the WTA criterion were not able to achieve a solution before the maximum number of evaluations.
Waste Management Practices and Profile of Selected Key Green House Gases at Selected Livestock Farms in Ibadan, Nigeria

Livestock farm waste contributes substantially to annual worldwide emissions of GHG (Greenhouse Gases), including CH4 (Methane) and CO2 (Carbon Dioxide). However, despite evidence of global climate change and its adverse health effects, studies on anthropogenic contributions to the increasing levels of GHG, particularly from livestock waste management practices, have not been adequately explored, especially in less developed countries. This study determined waste management practices and outdoor levels of CH4 and CO2 at three selected livestock farms (A-C) in Ibadan, Oyo State, Nigeria. Each study farm consisted of poultry, cattle and pig units. A 30-point observational checklist documented adequacy of solid waste management practices. Ambient concentrations of CH4 and CO2 at farm buildings and at waste disposal sites were monitored every other day, twice each day of monitoring (morning and evening hours), for eight weeks during months of September-November in 2013. Average scores for the waste management practices for Farms A-C were 29.6%, 33.3% and 18.5%, respectively. Morning and evening CH4 concentrations in parts per million (ppm) at main buildings of Farms A-C were 2,538 ± 773 and 1,916 ± 662, 2,325 ± 773 and 1,180 ± 483, and 2,389 ± 687 and 1,854 ± 571, respectively. Morning and evening CO2 concentrations (ppm) at Farms A-C main buildings were 350 ± 130 and 330 ± 110, 470 ± 100 and 440 ± 100, and 430 ± 80 and 400 ± 70, respectively. Morning and evening CH4 concentrations (ppm) at Farms A-C waste disposal sites were 2,452 ± 495 and 1,614 ± 372, 1,527 ± 390 and 1,736 ± 269, and 2,345 ± 615 and 1,690 ± 387, respectively. Morning and evening CO2 concentrations (ppm) at Farms A-C waste disposal sites were 330 ± 90, 370 ± 60 and 350 ± 30, respectively. Waste management practices were inadequate; solid waste management practices like infrequent evacuation of slurry waste and open burning of waste may have contributed to the production of CH4 and CO2. This study suggested proper handling, removal and disposal of farm waste which can reduce production of GHGs like CH4 and CO2.
The morphologies and masses of extremely red galaxies in the Groth Strip

We present a new catalogue of EROs from the Groth Strip and study the relation between their morphology and mass. With a selection criterion F814W−K_s≥ 4 and K_s≤ 21.0 we find 102 EROs, over a survey area of 155 arcmin^2, leading to a surface density of 0.66 arcmin^−2. The photometric data include U, B, F606W, F814W, J, Ks bands. Morphologies are based on a by eye classification and we distinguish between three basic classes: compact objects, targets with a disc and/or a bulge component and irregular or merger candidates. An additional group consists of the few objects which could not be classified. The majority of our targets has either a very compact morphology (34 ± 6 per cent), or show more or less distinct disc components (43 ± 6 per cent). 14 ± 4 per cent are merger or irregulars and seven objects (approximately 9 per cent) could not be classified. We also study the dependence of structural parameters (effective radius: r_eff, Sersic index: n) on morphological appearance. As expected, EROs that are either compact or show a distinct bulge component have smaller median effective radii (1.22 ± 0.14 kpc and 3.31 ± 0.53 kpc) than disc dominated (5.50 ± 0.51 kpc) or possible irregular galaxies or merger candidates (4.92 ± 0.14 kpc). More importantly, the Sersic index changes from 2.30 ± 0.34 and 3.24 ± 0.55, to 1.03 ± 0.24 and 1.54 ± 0.40, respectively. As found in previous studies, most the EROs in our sample have redshifts between z= 1 and 2; however, compact EROs in our sample are found at redshifts as low as z= 0.4 and as high as z= 2.8; the latter qualify as well as distant red galaxies (DRGs). Disc-like EROs are also found up to z= 2.8; however, those with a bulge-disc structure are only seen at z < 1.5. For each of these EROs we determined the stellar mass and mean population age by fitting synthetic Bruzual (2007) spectra to the photometric spectral energy distributions, via χ^2 minimization. Mass estimates were obtained by assuming an exponentially declining star formation rate with a wide set of parameters, e.g. decay time, redshift of last star formation, metallicity and optical depth. Total stellar masses for our sample are in the range 9.1 11.0 dominantly show compact morphologies, but also include a significant number of sources with a disc morphology.