64 research outputs found
Comparative Study of Financial Distress Prediction Models: Evidence from Pakistan
Traditional financial distress prediction models performed well for the developed markets, however, their applicability and predictability is limited for the emerging markets especially during the financial crisis.
This paper compares the predictability of five most widely used distress prediction models developed by Altman (1968), Ohlson (1980), Zmijewski (1984), Shumway (2001) and Blums (2003) by using up-todate data of emerging market from 2001 to 2015. Furthermore, the study tested the predictive power of the models before, during and after the financial crisis period. Results showed that Probit model has the higher overall prediction accuracy but the Z-Score more accurately predict financially distressed firms of emerging markets. Both models can be used by researchers, organizations and all other concerned parties to indicate early warning signs for the emerging markets. An important contribution of the paper is the definition of financial distress for the emerging markets where there are no databases with this type of classification. Along with the detailed criteria to classify distressed and non-distressed firms with the large time frame and data set, the study identifies the best predictor of financial distress. This paper also contributes to the literature by checking the changes in the predictability of the models with respect to the financial crisi
Study of strange quark density fluctuations in Au+Au Collisions at = 7.7-200 GeV from AMPT Model
The strangeness production is an important observable to study the QCD phase
diagram. The yield ratios of strange quark can be helpful to search for the QCD
critical point and/or first order phase transition. In this work, we studied
the production of , , and in Au+Au collisions at = 7.7, 11.5, 14.5, 19.6, 27,
39, 54.4, 62.4 and 200 GeV from A Multi-Phase Transport model with string
melting version (AMPT-SM). We calculated the invariant yield of these strange
hadrons using a different set of parameters reported in earlier studies and
also by varying the hadronic cascade time () in the AMPT-SM model. We
also calculated the yield ratios, which are sensitive to the strange quark
density fluctuations and found that the AMPT-SM model fails to describe the
non-monotonic trend observed by the STAR experiment. The negative particle
ratio are found to be higher than the ratio of positive particles which is
consistent with the experimental data. A significant effect is also seen on
these ratios by varying the . This study based on the transport model
can be helpful to provide possible constraints as well as reference for the
search of CEP in future heavy-ion experiments. Our findings suggest that the
ongoing Beam Energy Scan program at RHIC and the future heavy-ion experiments
will be able to find/locate the possible CEP in the QCD phase diagram which
results large quark density fluctuations.Comment: 7 pages, 2 figure
Effect of hadronic cascade time on freeze-out properties of Identified Hadrons in Au+Au Collisions at = 7.7-39 GeV from AMPT Model
We report the transverse momentum spectra of identified hadrons
(, and ) in Au+Au collisions at =
7.7 - 39 GeV from A Multi Phase Transport Model with string melting effect
(AMPT-SM). During this study, a new set of parameters are explored to study the
effect of hadronic cascade by varying hadronic cascade time = 30
m/ and 0.4 m/. No significant effect of this change is observed in
the spectra of light hadrons and the AMPT-SM model reasonably reproduces
the experimental data. To investigate the kinetic freeze-out properties the
blast wave fit is performed to the spectra and it is found that the blast
wave model describes the AMPT-SM simulations well. We additionally observe that
the kinetic freeze-out temperature () increases from central to
peripheral collisions, which is consistent with the argument of short-lived
fireball in peripheral collisions. Whereas the transverse flow velocity,
shows a decreasing trend from central to peripheral collisions
indicating a more rapid expansion in the central collisions. Both, $T_{kin}$
and show a weak dependence on the collision energy at most
energies. We also observe a strong anti-correlation between and
. The extracted freeze-out parameters from the AMPT-SM simulations
agree with the experimental data as opposed to earlier studies that reported
some discrepancies. Whereas, no significant effect is found on the freeze-out
parameters by varying the . We also report the spectra of light
hadrons and their freeze-out parameters by AMPT-SM simulations at
= 14.5 GeV, where no experimental data is available for
comparison. Overall, the set of parameters used in this study well describes
the experimental data at BES energies.Comment: 12 pages, 7 figures, 2 table
Synthesis and Functionalization of Monodisperse Near-ultraviolet and Visible Excitable Multifunctional Eu3+, Bi3+:REVO4 Nanophosphors for Bioimaging and Biosensing Applications
Near-ultraviolet and visible excitable Eu- and Bi-doped NPs based on rare earth vanadates (REVO4, RE = Y, Gd) have been synthesized by a facile route from appropriate RE precursors, europium and bismuth nitrate, and sodium orthovanadate, by homogeneous precipitation in an ethylene glycol/water mixture at 120 °C. The NPs can be functionalized either by a one-pot synthesis with polyacrylic acid (PAA) or by a Layer-by-Layer approach with poly(allylamine hydrochloride) (PAH) and PAA. In the first case, the particle size can also be tuned by adjusting the amount of PAA. The Eu- Bi-doped REVO4 based nanophosphors show the typical red luminescence of Eu(III), which can be excited through an energy transfer process from the vanadate anions, resulting in a much higher luminescence intensity in comparison to the direct excitation of the europium cations. The incorporation of Bi into the REVO4 structure shifts the original absorption band of the vanadate anions towards longer wavelengths, giving rise to nanophosphors with an excitation maximum at 342 nm, which can also be excited in the visible range. The suitability of such nanophosphors for bioimaging and biosensing applications, as well as their colloidal stability in different buffer media of biological interest, their cytotoxicity, their degradability at low pH, and their uptake by HeLa cells have been evaluated. Their suitability for bioimaging and biosensing applications is also demonstrated.European Union 267226Ministerio de Economía y Competitividad MAT2014-54852-
Study of Baryon number transport using model simulations in collisions at LHC Energies
We report on the excitation function of anti-baryon to baryon ratios
(, {\alam /\lam} and {\axi / \xim}) in collisions at
{\sqrts} = 0.9, 2.76, 7 TeV from DPMJET-III, Pythia~8, EPOS~1.99, and EPOS-LHC
model simulations. To study the predictions of these models at {\sqrts} = 13.6
TeV. The anti-baryon to baryon ratios are extremely important for the study of
baryon number transport mechanisms. These ratios help determine the carriers of
the baryon number and in the extraction of baryon structure information. Even
though all models show a good agreement between model simulations and data, the
ratios extracted from DPMJET-III model closely describes data at all energies.
It is observed that these ratios converge to unity for various model
predictions. This convergence also indicates that the anti-baryon to baryon
ratios follow the mass hierarchy, such that the hyperon specie containing more
strange quarks ({\alam /\lam} and {\axi / \xim}) approaches unity faster than
specie containing fewer strange quarks (). It is also observed
that the ratio approaches unity more rapidly with the increase
in {\sqrts} energy. At lower energies we observe an excess production of
baryons over anti-baryons. However, this effect vanishes at higher energies due
to the baryon-anti-baryon pair production and the baryon-anti-baryon yield
becomes equal. Using model simulations, we additionally compute the asymmetry,
(A\equiv\frac{N_{p}-N_{\bar{p}}}N_{p}+N_{\bar{p}}}) for protons. The
asymmetry shows a decreasing trend with increase in energy from 0.9 to 7 TeV
for all energies. This asymmetry trend is confirmed by model predictions at
{\sqrts} = 13.6 TeV which will help to put possible constraints on model
calculations at {\sqrts} = 13.6 TeV once the Run-III data for LHC becomes
available.Comment: 14 pages, 8 figures, 2 table
Bioconcentration of some macrominerals in soil, forage and buffalo hair continuum: A case study on pasture irrigated with sewage water
AbstractThe present study aimed to evaluate the bioaccumulation of some macrominerals in grazing buffaloes fed forage irrigated with sewage water or canal water. In particular, the transfer of sodium (Na), magnesium (Mg), potassium (K) and calcium (Ca) from soil to plant and in turn to animals was evaluated under sub-tropical environmental conditions. Samples of soil, forage and buffalo hair were collected and digested by wet method. Sodium and K concentrations were significantly higher in the soil but lower in the forages; however, Mg and Ca concentrations in both soil and forages were higher. The correlation between soil, forage and hair showed an imbalanced flow of Na, Mg and K and a balanced flow of Ca from soil to forage and then to animals. Based on the findings, the highest rates of transfer of minerals were found for sewage water treatment, whereas lowest rates were found for canal water treatment, except for Na. As the transfer of minerals depends on their bioavailability, the highest values may be due to the high rates of mineral uptake by plants. Thus, the high transfer rate of some elements by plants could become toxic in future causing detrimental effect to grazing livestock
Comparison of the International Crowding Measure in Emergency Departments (ICMED) and the National Emergency Department Overcrowding Study (NEDOCS) in Tertiary Care Hospital to Measure Emergency Department Crowding
Objective: To compare NEDOCS with ICMED in predicting clinicians' concerns regarding crowding in the Emergency Department of a tertiary care hospital in Pakistan.
Study Design: Prospective comparative study.
Place and Duration of Study: Accident & Emergency Department, Pak Emirates Military Hospital, Rawalpindi Pakistan, from Dec 2021 to Jan 2022.
Methodology: This study was conducted at the Accident and Emergency Department over 14 different days, 30 data sets of 3-hour intervals each were collected using the NEDOCS and ICMED proforma. NEDOCS Scores and ICMED scores were calculated. In addition, perceptions of the staff regarding crowding and danger to the patient's status were recorded on Visual Analogue scales.
Results: The mean recorded NEDOCS score was 577.94±251.57, with 29 'extremely overcrowded' and 1 'overcrowded' data set.The mean ICMED score was 2.86±0.83. Twenty-four (80%) sets did not have crowding, with only six (20%) sets being categorized as 'crowded'. The NEDOCS score had a moderately positive correlation with the crowding perception of the staff (Correlation coefficient (r)=0.593).
Conclusion: NEDOCS was a more suitable measure for recording ED crowding in Pakistan, as it recorded the quantitative component of waiting time. ICMED, on the other hand, only recorded waiting time on a binary scale, with the waiting time impact not translated fully on the total score
Quantitative uptake of colloidal particles by cell cultures
The use of nanotechnologies involving nano- and microparticles has increased tremendously in the recent past. There are various beneficial characteristics that make particles attractive for a wide range of technologies. However, colloidal particles on the other hand can potentially be harmful for humans and environment. Today, complete understanding of the interaction of colloidal particles with biological systems still remains a challenge. Indeed, their uptake, effects, and final cell cycle including their life span fate and degradation in biological systems are not fully understood. This is mainly due to the complexity of multiple parameters which need to be taken in consideration to perform the nanosafety research. Therefore, we will provide an overview of the common denominators and ideas to achieve universal metrics to assess their safety. The review discusses aspects including how biological media could change the physicochemical properties of colloids, how colloids are endocytosed by cells, how to distinguish between internalized versus membrane-attached colloids, possible correlation of cellular uptake of colloids with their physicochemical properties, and how the colloidal stability of colloids may vary upon cell internalization. In conclusion three main statements are given. First, in typically exposure scenarios only part of the colloids associated with cells are internalized while a significant part remain outside cells attached to their membrane. For quantitative uptake studies false positive counts in the form of only adherent but not internalized colloids have to be avoided. pH sensitive fluorophores attached to the colloids, which can discriminate between acidic endosomal/lysosomal and neutral extracellular environment around colloids offer a possible solution. Second, the metrics selected for uptake studies is of utmost importance. Counting the internalized colloids by number or by volume may lead to significantly different results. Third, colloids may change their physicochemical properties along their life cycle, and appropriate characterization is required during the different stages.This work was supported by the European Commission (grant FutureNanoNeeds) grant agreement no. 604602 to WJP. NF acknowledges funding from the Lars Hiertas Minne Fundation (Sweden), SA, BP and IC acknowledge a fellowship from the Alexander von Humboldt Fundation (Germany). AE acknowledges Junta de Andalucía (Spain) for a Talentia Postdoc Fellowship, co-financed by the European Union Seventh Framework Programme, grant agreement no 267226. AHS acknowledges the Egyptian government (Ministry of Higher Education, Mission). The project was also supported by the Dr. Dorka-Stiftung (Germany) to PJ
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