715 research outputs found
A Conceptual UX-aware Model of Requirements
User eXperience (UX) is becoming increasingly important for success of
software products. Yet, many companies still face various challenges in their
work with UX. Part of these challenges relate to inadequate knowledge and
awareness of UX and that current UX models are commonly not practical nor well
integrated into existing Software Engineering (SE) models and concepts.
Therefore, we present a conceptual UX-aware model of requirements for software
development practitioners. This layered model shows the interrelation between
UX and functional and quality requirements. The model is developed based on
current models of UX and software quality characteristics. Through the model we
highlight the main differences between various requirement types in particular
essentially subjective and accidentally subjective quality requirements. We
also present the result of an initial validation of the model through
interviews with 12 practitioners and researchers. Our results show that the
model can raise practitioners' knowledge and awareness of UX in particular in
relation to requirement and testing activities. It can also facilitate
UX-related communication among stakeholders with different backgrounds.Comment: 6th International Working Conference on Human-Centred Software
Engineerin
The vertical structure of galactic discs: nonlocal gravity versus dark matter
Recent isolated galactic simulations show that the morphology of galactic
discs in modified gravity differs from that of the standard dark matter model.
In this study, we focused on the vertical structure of galactic discs and
compared the bending instability in the vertical direction for both paradigms.
To achieve this, we utilized high-resolution N-body simulations to construct
two models in a specific nonlocal gravity theory (NLG) and the standard dark
matter model and compared their stability against the bending perturbations.
Our numerical results demonstrate that the outer regions of the disc are more
susceptible to the instability in NLG, whereas the disc embedded in the dark
matter halo is more unstable in the central regions. We then interpret these
results based on the dispersion relation of the bending waves. To do so, we
presented an analytical study to derive the dispersion relation in NLG. Our
numerical results align with the predictions of our analytical models.
Consequently, we conclude that the analysis of bending instability in galactic
discs offers an explanation for the distinct vertical structures observed in
simulated galactic discs under these two theories. These findings represent a
significant step towards distinguishing between the modified gravity and dark
matter models.Comment: 15 pages, 13 figures, Accepted for publication in MNRA
How could local communities regulate the assessment of the overlooked environmental and social impacts?
Environmental impact assessment (EIA) is a process to determine the significant environmental and social impacts of a proposed project to put forward strategies for preventing or mitigating the impacts. While the legal requirement for EIA procedure is the same, case studies throughout the world illustrate occasions of overlooked environmental and social impacts. This could be either due to the division between environmental and social impacts during the assessment or caused by the failure to adopt proper strategies particularly for mitigation of the impacts. This can affect local communities whose life is directly dependent on their surrounding ecosystem. Therefore, in order to fill the gap between law and social reality, this chapter, based on a body of theories concerning regulation, proposes that through using qualitative engagement methods, there is the capacity for local communities to participate in the process of impact identification meaningfully to ensure impacts are properly listed and ranked in the EIA, and social license to operate (SLO) plays a key role in granting local communities the authority to do so because otherwise there will be financial and reputational risks for companies
Cosmological Dynamics of Relativistic MOND
In this paper, we investigate the recently proposed relativistic theory for
MOND using the phase space analysis. Unlike its precedent theory, namely TeVeS,
this theory is claimed to agree with the observed Cosmic Microwave Background
and matter power spectra. We convert the background cosmological equations of
the theory to a set of first-order autonomous equations. Then we explore the
corresponding critical points and their physical meaning. This method is
powerful in the sense that the cosmological behavior of the model is diagnosed
independently of the magnitude of the free parameters of the theory. We show
that the theory has a viable sequence of cosmological epochs. Although using
specific initial conditions, this theory mimics the standard cosmological
model; it provides a richer structure as far as the background cosmology is
concerned. This implies that further investigations are required to see if this
theory contributes to addressing the current cosmological tensions.Comment: 18 pages, 10 figures, 2 tables. Some minor improvements are mad
The dual role of iNOS in cancer☆
Nitric oxide (NO) is one of the 10 smallest molecules found in nature. It is a simple gaseous free radical whose predominant functions is that of a messenger through cGMP. In mammals, NO is synthesized by the enzyme nitric oxide synthase (NOS) of which there are three isoforms. Neuronal (nNOS, NOS1) and endothelial (eNOS, NOS3) are constitutive calcium-dependent forms of the enzyme that regulate neural and vascular function respectively. The third isoform (iNOS, NOS2), is calcium-independent and is inducible. In many tumors, iNOS expression is high, however, the role of iNOS during tumor development is very complex and quite perplexing, with both promoting and inhibiting actions having been described. This review will aim to summarize the dual actions of iNOS-derived NO showing that the microenvironment of the tumor is a contributing factor to these observations and ultimately to cellular outcomes
Development of Slot-Less Linear Oscillatory Actuator
Linear Oscillatory Actuator (LOA) is an electromechanical device that can produce
short linear stroke motion directly without the use of any mechanical transmission to
convert rotary motion into linear motion. Due to this simplicity, the benefits of LOA
over conventional actuator are simple structure, better dynamical performance, and
higher reliability. It has been extensively used in industry applications especially in
power generation, healthcare, factory automation, and household appliances.
Currently, most of the researches are only dealing with designing a slot type of LOA
with exact values of thrust, electrical time constant, and mechanical time constant.
Some of them studied the control strategy of an existing moving coil type of LOA.
But, none of them had disclosed information about the oscillation displacement
characteristics based on various sizes of LOA. Such information is useful for the
designer. It will provide solutions or guidelines about the thrust constant, spring
constant, electrical time constant, and mechanical time constant toward oscillation
displacement characteristics of LOA. The analysis of the parameters mentioned above definitely will help any researchers to know whether the LOA is suitable for
the specific application before design the optimized structure for fabrication.
Unfortunately, the information as mentioned above is not available to the designers.
This thesis describes the development and analysis on the effect of thrust constant,
spring constant, electrical time constant, and mechanical time constant to oscillation
displacement characteristic of slot-less linear oscillatory actuator. The analysis is
necessary to determine the variation and relationship of these constants to various
sizes of LOA. In this research, a prototype of slot-less linear oscillatory actuator is
designed using Finite Element Method (FEM). The prototype is fabricated and
measured experimentally. Moreover, analytical solution is developed for the same
prototype using Permeance Analysis Method (PAM). The two methods were verified
through comparison with measurement. The comparison shows the proposed
analytical solution using PAM had good agreement with both FEM and the
measurement.
As summary, the research found that the constants affect the oscillation displacement
to be higher but the thrust would become lower for small size of LOA. In contrary,
high thrust can be achieved for bigger size of LOA but the oscillation displacement
would become lower. Therefore, in order to design high thrust LOA the lower value
of electrical time constant and mechanical time constants should be selected.
Meanwhile, for both thrust constant and spring constant higher value should be
selected. For designing higher oscillation displacement of LOA, the lower value of
electrical time constant, thrust constant, and spring constant should be selected where
as for mechanical time constant higher value should be selected
Flurbiprofen benzyl nitrate (NBS-242) inhibits the growth of A-431 human epidermoid carcinoma cells and targets β-catenin
Background: The Wnt/β-catenin/T cell factor (TCF) signaling pathway is important in the development of nonmelanoma skin cancers (NMSCs). Nitric-oxide-releasing nonsteroidal anti-inflammatory drugs (NO-NSAIDs) are chemopreventive agents consisting of a traditional NSAID attached to an NO-releasing moiety through a chemical spacer. Previously we showed that an aromatic spacer enhanced the potency of a particular NO-NSAID compared to an aliphatic spacer.
Methods: We synthesized an NO-releasing NSAID with an aromatic spacer (flurbiprofen benzyl nitrate, NBS-242), and using the human skin cancer cell line A-431, we evaluated its effects on cell kinetics, Wnt/β-catenin, cyclin D1, and caspase-3.
Results: NBS-242 inhibited the growth of A-431 cancer cells, being ∼15-fold more potent than flurbiprofen and up to 5-fold more potent than NO-flurbiprofen with an aliphatic spacer, the half maximal inhibitory concentrations (IC50) for growth inhibition being 60 ± 4 μM, 320 ± 20 μM, and 880 ± 65 μM for NBS-242, NO-flurbiprofen, and flurbiprofen, respectively. This effect was associated with inhibition of proliferation, accumulation of cells in the G0/G1 phase of the cell cycle, and an increase in apoptotic cell population. NBS-242 cleaved β-catenin both in the cytoplasm and the nucleus of A-431 cells. NBS-242 activated caspase-3 whose activation was reflected in the cleavage of procaspase-3. To test the functional consequence of β-catenin cleavage, we determined the expression of cyclin D1, a Wnt-response gene. NBS-242 reduced cyclin D1 levels in a concentration dependent manner.
Conclusion: These findings establish a strong inhibitory effect of NBS-242 in A-431 human epidermoid carcinoma cells. NBS-242 modulates parameters that are important in determining cellular mass. Keywords: flurbiprofe
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