1,175 research outputs found
PENGARUH SOCIAL MEDIA ENGAGEMENT DAN BRAND TRUST TERHADAP BRAND ADVOCACY: Survei terhadap Pelanggan Erigo pada platform Shopee di Indonesia
This study aims to obtain an overview and influence of social media involvement and brand trust on brand advocacy for Erigo customers through the Shopee platform in Indonesia. This research uses descriptive and verification methods with a quantitative approach. The sample of this research is 200 respondents who are Erigo customers who make reviews on the Shopee platform in Indonesia. The data were processed statistically using the Structural Equation Modeling (SEM) method. The findings in this study found that the descriptions of social media engagement, brand trust and brand advocacy were in a fairly good category. Social media engagement and brand trust have a positive influence on brand advocacy. These findings show that the application of social media engagement and brand trust creates brand advocacy for Erigo customers through Shopee in Indonesia
The Use of Mobile Phones Among Trishaw Operators in Myanmar
This article examines use of mobile phones by trishaw (rickshaw) operators in the newly emerging techno-landscape of Myanmar. Trishaw operators transport people and goods in a physically demanding job that often earns them as little as US1,500 to US$1.50, making it affordable to groups that heretofore have not had access. We find that the trishaw sector is changing because of this. The mobile phone strengthens ties with important clients, meaning a more stable income, but also an enhanced importance/power for these customers. Operators who have not adopted mobile phones, usually because of poverty, age, or a lack of interest, will likely have fewer business opportunities
Respiration predicted from an Enzyme Kinetic Model and the Metabolic Theory of Ecology in two species of marine bacteria
12 pages, 8 figures, 5 tablesRespiratory oxygen consumption is the result of a cell's biochemistry. It is caused by enzymatic activity of the respiratory electron transfer system (ETS). However, in spite of this understanding, respiration models continue to be based on allometric equations relating respiration to body size, body surface, or biomass. The Metabolic Theory of Ecology (MTE) is a current example. It is based on Kleiber's law relating respiration (R) and biomass (M) in the form, View the MathML source, where C is a constant, Ea is the Arrhenius activation energy, k is the Boltzmann constant for an atom or molecule, and T is the temperature in Kelvin. This law holds because biomass packages the ETS. In contrast, we bypass biomass and model respiration directly from its causal relationship with the ETS activity, R = f (ETS). We use a biochemical Enzyme Kinetic Model (EKM) of respiratory oxygen consumption based on the substrate control of the ETS. It postulates that the upper limit of R is set by the maximum velocity, Vmax, of complex I of the ETS and the temperature, and that the substrate availability, S, modulates R between zero and this upper limit. Kinetics of this thermal-substrate regulation is described by the Arrhenius and Michaelis–Menten equations. The EKM equation takes the form View the MathML source where Rg is the molar gas constant and K is the Michaelis–Menten constant.
Here, we apply the EKM and the MTE to predict a respiration time-profile throughout the exponential, steady state, and nutrient-limited phases of the marine bacteria Pseudomonas nautica and Vibrio natriegens in acetate-based cultures. Both models were tested by comparing their output with the measured RO2 time-profile. The MTE predicted respiration accurately only in the exponential growth phase, but not during the nutrient limitation part of the stationary phase. In contrast, the EKM worked well throughout both physiological phases as long as the modeled substrates fall with the declining carbon source. Results support the theoretical bases of the EKM. We conclude that the EKM holds promise for predicting respiration at the different physiological states and time-scales important to microbiological studiesFinancial support was provided by the Universidad de Las Palmas de Gran Canaria (ULPGC), the Spanish Ministry of Education and Science, the Graduate Program in Oceanography at the ULPGC, ICM-CSIC, and the research grants MODIVUS (CTM2005-04795/MAR), EXOME (CTM 2008-01616), and OITHONA (CTM2007-60052). T. Packard was supported by contract EXMAR SE-539 10/17 (Proyecto Estructurante en Ciencias Marinas). This is contribution #200906 from the Bigelow Laboratory for Ocean SciencesPeer reviewe
Voices of Subaltern. Introduction to the special issue
The Social Exclusion and Pedagogy in the Welfare State (SEP) research program, Aarhus University, Denmark has focused on this theme based on giving voice to the subalterns, which in the modern welfare state include i.e. the vulnerable, the excluded, stigmatized and socially marginalized groups in society
Steam Gasification of Lignite in a Bench-Scale Fluidized-Bed Gasifier Using Olivine as Bed Material
The gasification of lignite could be a promising sustainable alternative to combustion, because it causes reduced emissions and allows the production of syngas, which is a versatile gaseous fuel that can be used for cogeneration, Fischer-Tropsch synthesis, or the synthesis of other bio-fuels, such as methanol. For the safe and smooth exploitation of syngas, it is fundamental to have a high
quality gas, with a high content of H2 and CO and minimum content of pollutants, such as particulate and tars. In this work, experimental tests on lignite gasification are carried out in a bench-scale fluidized-bed reactor with olivine as bed material, chosen for its catalytic properties that can enhance tar reduction. Some operating parameters were changed throughout the tests, in order to study their influence on the quality of the syngas produced, and pressure fluctuation signals were acquired to evaluate the fluidization quality and diagnose correlated sintering or the agglomeration of bed particles. The e ect of temperature and small air injections in the freeboard were investigated and evaluated in terms of the conversion eciencies, gas composition, and tar produced.The authors kindly acknowledge the financial support
of the European Project LIG2LIQ (RFCS-01-2017 GA796585)
co-funded by the European Commission managed Research Fund for
Coal and Steel (RFCS)
The Diversity of Core Halo Structure in the Fuzzy Dark Matter Model
In the fuzzy dark matter (FDM) model, gravitationally collapsed objects
always consist of a solitonic core located within a virialised halo. Although
various numerical simulations have confirmed that the collapsed structure can
be described by a cored NFW like density profile, there is still disagreement
about the relation between the core mass and the halo mass. To fully understand
this relation, we have assembled a large sample of cored haloes based on both
idealised soliton mergers and cosmological simulations with various box sizes.
We find that there exists a sizeable dispersion in the core-halo mass relation
that increases with halo mass, indicating that the FDM model allows cores and
haloes to coexist in diverse configurations. We provide a new empirical
equation for a core halo mass relation with uncertainties that can encompass
all previously found relations in the dispersion, and emphasise that any
observational constraints on the particle mass using a tight one-to-one
core-halo mass relation should suffer from an additional uncertainty on the
order of 50 % for halo masses . We suggest that tidal stripping may be one of the effects
contributing to the scatter in the relation
Prevalence of Human Intestinal Entamoeba spp. in the Americas: A Systematic Review and Meta-Analysis, 1990–2022
Among the seven species of Entamoeba known to infect humans, E. histolytica is widely recognized as a pathogen. It is reported that Entamoeba infections are common in the developing world, but rare in developed countries. The best way to diagnose these protozoan parasites is to detect antigens or DNA in the stool. This study aimed to review the prevalence, distribution, and diagnosis methods of Entamoeba spp. infecting humans in the Americas between 1990 and 2022. A systematic review and meta-analysis were performed, including 227 studies on Entamoeba infections from 30 out of 35 American countries. The pooled prevalence of each species of Entamoeba was calculated using the random-effects model. The assignment of Entamoeba species was mainly performed by microscopy. The most widely distributed and prevalent species was E. coli (21.0%). Of the studies, 49% could not differentiate the species of the Entamoeba complex. The pathogenic species E. histolytica was distributed among 22 out of 30 American countries studied, with a pooled prevalence of 9%. Molecular data on Entamoeba species are still scarce. This is the first study that reviewed and summarized data on the prevalence of this protozoan genera among American countries.Fil: Servian, Andrea. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Helman, MarÃa Elisa. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Departamento de EpizootiologÃa y Salud Pública. Laboratorio de InmunoparasitologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - La Plata; ArgentinaFil: Iglesias, MarÃa del Rosario. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Panti May, Jesús Alonso. Universidad Autonoma de Yucatan (uady);Fil: Zonta, Maria Lorena. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Navone, Graciela Teresa. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; Argentin
A lensed radio jet at milli-arcsecond resolution II: Constraints on fuzzy dark matter from an extended gravitational arc
Using a single gravitational lens system observed at
milli-arcsecond resolution with very long baseline interferometry (VLBI), we
place a lower bound on the mass of the fuzzy dark matter (FDM) particle, ruling
out with a 20:1 posterior odds
ratio relative to a smooth lens model. We generalize our result to non-scalar
and multiple-field models, such as vector FDM, with . Due to the extended source structure and high
angular resolution of the observation, our analysis is directly sensitive to
the presence of granule structures in the main dark matter halo of the lens,
which is the most generic prediction of FDM theories. A model based on
well-understood physics of ultra-light dark matter fields in a gravitational
potential well makes our result robust to a wide range of assumed dark matter
fractions and velocity dispersions in the lens galaxy. Our result is
competitive with other lower bounds on from past analyses, which rely
on intermediate modelling of structure formation and/or baryonic effects.
Higher resolution observations taken at 10 to 100 GHz could improve our
constraints by up to 2 orders of magnitude in the future.Comment: 5 pages, 2 figures. Accepted in MNRAS Letter
Steam Gasification of Lignite in a Bench-Scale Fluidized-Bed Gasifier Using Olivine as Bed Material
The gasification of lignite could be a promising sustainable alternative to combustion, because it causes reduced emissions and allows the production of syngas, which is a versatile gaseous fuel that can be used for cogeneration, Fischer-Tropsch synthesis, or the synthesis of other bio-fuels, such as methanol. For the safe and smooth exploitation of syngas, it is fundamental to have a high quality gas, with a high content of Hâ‚‚ and CO and minimum content of pollutants, such as particulate and tars. In this work, experimental tests on lignite gasification are carried out in a bench-scale fluidized-bed reactor with olivine as bed material, chosen for its catalytic properties that can enhance tar reduction. Some operating parameters were changed throughout the tests, in order to study their influence on the quality of the syngas produced, and pressure fluctuation signals were acquired to evaluate the fluidization quality and diagnose correlated sintering or the agglomeration of bed particles. The effect of temperature and small air injections in the freeboard were investigated and evaluated in terms of the conversion efficiencies, gas composition, and tar produced
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