Miracle-dz/UniFAR-FTUs huggingface dataset:
Multiple-scales approach to the averaging problem in cosmology

The Universe is homogeneous and isotropic on large scales, so on those scales it is usually modelled as a Friedmann-Lemaítre-Robertson-Walker (FLRW) space-time. The non-linearity of the Einstein field equations raises concern over averaging over small-scale deviations form homogeneity and isotropy, with possible implications on the applicability of the FLRW metric to the Universe, even on large scales. Here I present a technique, based on the multiple-scales method of singular perturbation theory, to handle the small-scale inhomogeneities consistently. I obtain a leading order effective Einstein equation for the large-scale space-time metric, which contains a back-reaction term. The derivation relies on a series of consistency conditions, that ensure that the growth of deviations from the large-scale space-time metric do not grow unboundedly; criteria for their satisfiability are discussed, and it is shown that they are indeed satisfied if matter is non-relativistic on small scales. The analysis is performed in harmonic gauge, and conversion to other gauges is discussed. I estimate the magnitude of the back-reaction term relative to the critical density of the Universe in the example of an NFW halo, and find it to be of the order of a few percent. In this example, the back-reaction term is interpreted as a contribution of the energy-density of gravitational potential energy, averaged over the small-scale, to the total energy-momentum tensor.
Mediation effects that emulate a target randomised trial: Simulation-based evaluation of ill-defined interventions on multiple mediators

Many epidemiological questions concern potential interventions to alter the pathways presumed to mediate an association. For example, we consider a study that investigates the benefit of interventions in young adulthood for ameliorating the poorer mid-life psychosocial outcomes of adolescent self-harmers relative to their healthy peers. Two methodological challenges arise. First, mediation methods have hitherto mostly focused on the elusive task of discovering pathways, rather than on the evaluation of mediator interventions. Second, the complexity of such questions is invariably such that there are no well-defined mediator interventions (i.e. actual treatments, programs, etc.) for which data exist on the relevant populations, outcomes and time-spans of interest. Instead, researchers must rely on exposure (non-intervention) data, that is, on mediator measures such as depression symptoms for which the actual interventions that one might implement to alter them are not well defined. We propose a novel framework that addresses these challenges by defining mediation effects that map to a target trial of hypothetical interventions targeting multiple mediators for which we simulate the effects. Specifically, we specify a target trial addressing three policy-relevant questions, regarding the impacts of hypothetical interventions that would shift the mediators’ distributions (separately under various interdependence assumptions, jointly or sequentially) to user-specified distributions that can be emulated with the observed data. We then define novel interventional effects that map to this trial, simulating shifts by setting mediators to random draws from those distributions. We show that estimation using a g-computation method is possible under an expanded set of causal assumptions relative to inference with well-defined interventions, which reflects the lower level of evidence that is expected with ill-defined interventions. Application to the self-harm example in the Victorian Adolescent Health Cohort Study illustrates the value of our proposal for informing the design and evaluation of actual interventions in the future.
Early-type galaxies in the Antlia cluster: global properties

We present an extension of our previous research on the early-type galaxy population of the Antlia cluster (d ~ 35 Mpc), achieving a total coverage of ~ 2.6 deg x deg and performing surface photometry for ~300 galaxies, 130 of which are new uncatalogued ones. Such new galaxies mainly fall in the low surface brightness (LSB) regime, but there are also some lenticulars (S0) which support the existence of unique functions that connect bright and dwarf galaxies in the scaling relations. We analyse the projected spatial distribution of galaxies up to a distance of ~800 kpc from NGC 3268, the adopted centre, as well as the radial velocity distribution and the correlation between galaxy colour and effective radius with the projected spatial distribution. We also obtain the luminosity function of the early-type galaxies and the distribution of stellar masses using the T1-band magnitudes and adopted mass-luminosity ratios. Additionally, we correlate the central galaxy distribution with an X-ray emission map from the literature. Based on the analysis of the radial velocities and galaxy colour distributions, we find that galaxies redder than the colour-magnitude relation (CMR) have a velocity distribution strongly concentrated towards the values of the dominant galaxies and are homogeneously distributed throughout the cluster. Those bluer than the CMR, in turn, have a much more extended radial velocity distribution and are concentrated towards the centre of the cluster. We also identify 12 candidates to ultra diffuse galaxies (UDG), that seem to be split into two families, and speculate about their origins in the context of the cluster structure.
It Is Likely That Your Loss Should be a Likelihood

We recall that certain common losses are simplified likelihoods and instead argue for optimizing full likelihoods that include their parameters, such as the variance of the normal distribution and the temperature of the softmax distribution. Joint optimization of likelihood and model parameters can adaptively tune the scales and shapes of losses and the weights of regularizers. We survey and systematically evaluate how to parameterize and apply likelihood parameters for robust modeling and re-calibration. Additionally, we propose adaptively tuning $L_2$ and $L_1$ weights by fitting the scale parameters of normal and Laplace priors and introduce more flexible element-wise regularizers.
Temporal and spatial patterns based on sediment and sediment–water interface characteristics along a cascade of reservoirs (Paranapanema River, south‐east Brazil)

Physical and chemical characteristics of the sediments in a cascade of eight reservoirs located in the Paranapanema River (south-east Brazil) were analysed during two consecutive years during summer (January), autumn (April), winter (July) and spring (October) of 2000 and 2001, respectively. The granulometric texture, organic matter content and nutrient concentration (total nitrogen and phosphorus) were determined in the superficial sediment of 19 sampling stations, as well as the temperature, dissolved oxygen, pH, conductivity and redox potential in the bottom layer of the water column. Seasonal and spatial changes were observed for both years, especially for organic matter and nutrient concentrations. Three different areas could be identified along the river, which corresponded to the upper, middle and lower Paranapanema basin. The first area was characterized by an increase of nutrients and organic matter in the sediments and a decrease of temperature and dissolved oxygen in the downstream direction. The second one represented a region where fluctuations in nutrient and organic matter concentrations and a reduction in dissolved oxygen were observed. In the third area, there was an increase in nutrient and organic matter in the sediments and also an increase in temperature and dissolved oxygen towards the river mouth. The results of the principal components analysis, using water and sediments variables, showed the ordination of sampling stations by periods: wet (January–April) and dry (July–October) during 2000. This pattern was also verified during 2001, but with slight changes, probably due to the increase in the rains which would have produced certain homogenization effects along the river.
Special generic maps and fold maps and information on triple Massey products of higher dimensional differentiable manifolds

Closed (and simply-connected) manifolds whose dimensions are larger than 4 are central geometric objects in classical algebraic topology and differential topology. They have been classified via algebraic and abstract objects. On the other hand, It is difficult to understand them in geometric and constructive ways. In the present paper, we show such studies via explicit fold maps, higher dimensional versions of Morse functions. The author captured information of the topologies and the differentiable structures of closed (and simply-connected) manifolds which are not so complicated with respect to homotopy previously and cohomology rings of more general closed (and simply-connected) manifolds via construction of these maps. In the present paper, we capture more precise information on cohomology classes or so-called triple Massey products in this way as a related new work.
Shanks and Anderson-type acceleration techniques for systems of nonlinear equations

This paper examines a number of extrapolation and acceleration methods, and introduces a few modifications of the standard Shanks transformation that deal with general sequences. One of the goals of the paper is to lay out a general framework that encompasses most of the known acceleration strategies. The paper also considers the Anderson acceleration algorithm under a new light and exploits a connection with Quasi-Newton methods, in order to establish local linear convergence results of Anderson-type techniques. The methods are tested on a number of problems, including a few that arise from nonlinear Partial Differential Equations.
Multi-step Greedy Reinforcement Learning Algorithms

Multi-step greedy policies have been extensively used in model-based reinforcement learning (RL), both when a model of the environment is available (e.g.,~in the game of Go) and when it is learned. In this paper, we explore their benefits in model-free RL, when employed using multi-step dynamic programming algorithms: $\kappa$-Policy Iteration ($\kappa$-PI) and $\kappa$-Value Iteration ($\kappa$-VI). These methods iteratively compute the next policy ($\kappa$-PI) and value function ($\kappa$-VI) by solving a surrogate decision problem with a shaped reward and a smaller discount factor. We derive model-free RL algorithms based on $\kappa$-PI and $\kappa$-VI in which the surrogate problem can be solved by any discrete or continuous action RL method, such as DQN and TRPO. We identify the importance of a hyper-parameter that controls the extent to which the surrogate problem is solved and suggest a way to set this parameter. When evaluated on a range of Atari and MuJoCo benchmark tasks, our results indicate that for the right range of $\kappa$, our algorithms outperform DQN and TRPO. This shows that our multi-step greedy algorithms are general enough to be applied over any existing RL algorithm and can significantly improve its performance.
Using Track-plate Footprints in Fisher Mark Recapture Population Estimation

Abstract Obtaining accurate estimates of fisher (Martes pennanti) population abundance is challenging to resource management agencies given the large home ranges and low densities at which fisher occur. Current methods for estimating population abundance are expensive in terms of equipment required and hours worked indicating a need for a less labor and equipment intensive method. Track-plate footprinting is a method of individually identifying fisher by the papillae patterns found on the metacarpal pad. We evaluated the technique of track-plate footprinting as a mark-recapture method to estimate population abundance of fisher in the Ottawa National Forest of Michigan's Upper Peninsula. We placed covered track-plates using copy toner and a medium of contact paper as a method of obtaining footprints of fisher for individual identification. Over 1548 trap-nights we identified 24 prints from nine different fisher with four individuals being recaptured. Program Mark produced a population estimate of 13 animals with a 95% confidence interval of 8–20 animals. Our study shows that track-plate footprinting is a viable method for estimating population abundance of fisher under natural conditions.
Supervised learning in Hamiltonian reconstruction from local measurements on eigenstates

Reconstructing a system Hamiltonian through measurements on its eigenstates is an important inverse problem in quantum physics. Recently, it was shown that generic many-body local Hamiltonians can be recovered by local measurements without knowing the values of the correlation functions. In this work, we discuss this problem in more depth for different systems and apply supervised learning method via neural networks to solve it. For low-lying eigenstates, the inverse problem is well-posed, neural networks turn out to be efficient and scalable even with a shallow network and a small data set. For middle-lying eigenstates, the problem is ill-posed, we present a modified method based on transfer learning accordingly. Neural networks can also efficiently generate appropriate initial points for numerical optimization based on the BFGS method.
Optimising ripening temperatures of Cavendish bananas var. 'Williams' harvested throughout the year in Queensland, Australia

Varying banana ripening temperatures were examined throughout the year to ensure optimum quality and shelf life of commercially ripened fruit in Australia. Cavendish bananas (var. 'Williams') were harvested throughout the year 2000 and were ripened at 14, 16, 18 and 20°C with 300 μL/L ethylene on 2 consecutive days until fruit were more yellow than green and then subsequently stored at 22°C until the end of the experiment. Ripening bananas at 14 and 16°C extended shelf life by up to 50 and 32%, respectively. However, ripening bananas at 14 and 16°C did increase peel discolouration, especially on bananas chilled in the field in winter. Bananas ripened at 18 or 20°C throughout the year had an average shelf life of 6 days and consistently lower peel discolouration. Therefore, ripening at 18 or 20°C throughout the year results in a better visual appearance of the fruit, which is essential for consumers.
Post-Harvest Changes in Banana Cv. Robusta*

Banana bunches CV Robusta harvested, at three-fourth and full maturity and the hands separted and dipped in aqueous solution of TBZ 500 ppm or wax emulsion containing TBZ 500 ppm in combination with different growth regulating substances, were kept in open or in polythene bags at room temperature or at 15°C and 80–90 per cent R. H. The fruits not only remained firm at the early ripe stage but had prolonged shelf life with green and unshrivelled peels having narrow pulp/peel weight ratio and perfect peeling condition till the end of the shelf life, when stored in polythene bagsatl5°C and 80–90 per cent R. H. Loss in fruit weight during pre and post-ripening stages was less when treated with 8-HQ and stored in polythene bags. Colour development and fruit ripening were delayed when the fruits were treated with wax emulsion and stored in polythene bags. The shelf life and fruit quality were greater and the spoilage due to fungal infection was nil in the fruits treated with wax emulsion and stored in polythene bags containing KMnO4 and Ca(OH)2 and the shelf life and quality were further enhanced when stored at 15°C and 80–90 per cent R. H.
Differences in adrenocortical responses between urban and rural burrowing owls: poorly-known underlying mechanisms and their implications for conservation

Abstract The hypothalamus–pituitary–adrenal/interrenal (HPA) axis of vertebrates integrates external information and orchestrates responses to cope with energy-demanding and stressful events through changes in circulating glucocorticoid levels. Urbanization exposes animals to a wide variety of ever-changing stimuli caused by human activities that may affect local wildlife populations. Here, we empirically tested the hypothesis that urban and rural owls (Athene cunicularia) show different adrenocortical responses to stress, with urban individuals showing a reduced HPA-axis response compared to rural counterparts to cope with the high levels of human disturbance typical of urban areas. We applied a standard capture-restraint protocol to measure baseline levels and stress-induced corticosterone (CORT) responses. Urban and rural owls showed similar circulating baseline CORT levels. However, maximum CORT levels were attained earlier and were of lower magnitude in urban compared to rural owls, which showed a more pronounced and long-lasting response. Variability in CORT responses was also greater in rural owls and contained the narrower variability displayed by urban ones. These results suggest that only individuals expressing low-HPA-axis responses can thrive in cities, a pattern potentially mediated by three alternative and non-exclusive hypotheses: phenotypic plasticity, natural selection and matching habitat choice. Due to their different conservation implications, we recommend further research to properly understand wildlife responses to humans in an increasingly urbanized world.
Evaluating the additive effect of Persica and chlorhexidine mouthwashes on oral health status of children receiving chemotherapy for their hematomalignancy: A randomized clinical trial

Background No definitive protocol has been introduced for treatment or prevention of chemotherapy induced mucositis. The aim of this study was to assess the additive effect of Persica and chlorhexidine on chemotherapy induced mucositis of children with hematomalignancies. Material and Methods This randomized clinical trial was performed on 44 children aged 6 to 12 years who were under a similar maintenance chemotherapy protocol for their hematomalignancies. The clinician instructed oral hygiene cares to the patients and their parents and the severity of the mucositis and oral health status of patients were evaluated according to Oral Assessment Guide index. Then, the patients were randomly assigned to one of two experimental groups and were instructed to rinse either with Persica oral drops or normal saline, twice a day for two weeks. Subsequently, the patients in both groups were educated to rinse with chlorhexidine for 30 seconds and avoid eating for an hour. Second and third oral examinations were performed on the 8th and 15th day using the same questionnaire. Results Comparing severity of mucositis and oral health status of patients did not show any significant difference between treatment groups in either of examination sessions (p>0.05). However, both treatment groups showed statistically significant oral health improvement, in terms of mucositis, plaque accumulation and gingival condition, in 14 days following mouthrinses administration (p<0.05). Conclusions Both mouth-rinse combinations were effective on mucositis, plaque and gingival status of children receiving chemotherapy. However, Persica does not seem to pose additional effect on chlorhexidine in decreasing severity of chemotherapy induced mucositis. Key words:Mucositis, chemotherapy, children, chlorhexidine, Persica.
Spatial Variance in Soil Microarthropod Communities: Niche, Neutrality, or Stochasticity?

Abstract: We studied geographic patterns in the soil microarthropods associated with moss carpets on exposed rocky outcrops in southwestern British Columbia, Canada. We related microarthropod composition, abundance, and species richness to 15 ecological variables relevant to either spatial or environmental filtering. Our survey identified 352 morphospecies in 32 sites spanning a 130- × 60-km area. We tested whether the relative importance of spatial and environmental factors was concordant between community composition, abundance, species richness, and 3 major taxonomic groups (Oribatida, Mesostigmata, Collembola). The results depended on the variance partitioning methods used and whether composition was defined by species abundance or presence. Distance-based Mantel tests showed that dissimilarity in species composition between sites was better predicted by spatial distance than by environmental dissimilarity. In contrast, variance partitioning of ordinated abundance data concluded that environmental rather than spatial variables explained most variance in the composition of total microarthropod, especially Collembola, assemblages. Total abundance and species richness were only weakly correlated across space, even though both were explained by environmental factors such as temperature and soil moisture. Given the surprising contradictions between methods, we suggest that different analyses should always be compared to fully uncover the spatial and environmental factors structuring communities.
Assessing the Use of Standardized Outcome Measures for Stroke Rehabilitation among Physiotherapists in Ghana

Background The use of standardized outcome measures is an aspect of good clinical practice and essential to the rehabilitation of patients suffering from stroke. Literature reports regarding the extent of usage of outcome measures in stroke rehabilitation by physiotherapists globally are inconsistent. In addition, the patronage of outcome measures in stroke rehabilitation in low-resourced countries is uncertain. Objective This study was conducted to assess the current practice of physiotherapists in Ghana regarding the use of standardized outcome measures in the rehabilitation of stroke patients. Method A descriptive cross-sectional survey, was used involving 105 registered physiotherapists in Ghana. A 35-item adapted questionnaire was used to collect data on some commonly used outcome measures and frequency of use by physiotherapists for stroke patients. Results A total of 55 (52.4%) physiotherapists did not use outcome measures in their clinical practice. Physiotherapists below 40 years of age use outcome measures (64.7%) more than those 41 years and above (6.7%). Physiotherapists working in public facilities in Ghana are more likely to use outcome measures (56.2%) than those in private facilities (16.2%). Physiotherapists who attend to 1-10 patients in a week used outcome measures more (32.4%) than physiotherapists who attend to more than 30 patients (3.8%) in a week. Conclusion There is poor usage of outcome measures by Ghanaian physiotherapists, with more than half of the participants not using any standardized outcome measures for rehabilitation of patients in their practice. Physiotherapists who attends to fewer number of patients in a week are more likely to use outcome measures. There is the need for implementation of policy and guidelines on the use of outcome measures by the Allied Health Professions Council and the Ghana Physiotherapy Association.