Nanotechnology is a new and emerging technology with wealth of applications. It involves the synthesis and application of materials having one of the dimensions in the range of 1–100 nm. A wide ...variety of physico–chemical approaches are being used these days for the synthesis of nanoparticles (NPs). However, biogenic reduction of metal precursors to produce corresponding NPs is eco-friendly, less expensive, free of chemical contaminants for medical and biological applications where purity of NPs is of major concern. Biogenic reduction is a “Bottom Up” approach similar to chemical reduction where a reducing agent is replaced by extract of a natural products with inherent stabilizing, growth terminating and capping properties. Furthermore, the nature of biological entities in different concentrations in combination with reducing organic agents influence the size and shape of NPs. Present review focuses on microbes or plants based green synthesis of Ag, Au, Cu, Fe, Pd, Ru, PbS, CdS, CuO, CeO₂, Fe₃O₄, TiO₂, and ZnO NPs and their potential applications.
A matter-dominated model with gravitationally induced matter creation is proposed in the framework of Brans-Dicke theory. We obtain the main cosmological functions such as the scale factor of the ...Universe, the Hubble expansion rate, and the deceleration parameter analytically. We explore the viability of the model to explain the present accelerated expansion of the Universe. In this scenario, the present cosmic acceleration is supposed to be driven only by the negative creation pressure associated with the matter component. The evolution of such a model is tested by statistical analysis of the latest SNe, OHD, and BAO probes. We study and plot the trajectories of the evolution of the Universe with the best estimated values of the model parameters. It is observed that the expanding Universe begins with a big bang followed by a smooth transition from the decelerated phase to the accelerated phase. The ages of the Universe obtained by SNe+OHD and SNe+OHD+BAO in this model are in good agreement with the age predicted by the ΛCDM model. We analyze the model with a statefinder diagnostic and find that the model is different from the ΛCDM model but approaches ΛCDM in the future. The model shows quintessence behavior.
Uptake of family planning (FP) services could prevent many unwanted pregnancies, and unsafe abortions and avert maternal deaths. However, women, especially from ethnic and religious minorities, have ...a low practice of contraceptives in Nepal. This study examined the knowledge and practices of modern contraceptive methods among Muslim women in Nepal.
A cross-sectional study was conducted among 400 Muslim women in the Khajura Rural Municipality of Banke district. Data were collected using face to face structured interviews. Two outcome variables included i) knowledge of and ii) practices of contraceptives. Knowledge and practice scores were estimated using the list of questions. Using median as a cut-off point, scores were categorised into two categories for each outcome variable (e.g., good knowledge and poor knowledge). Independent variables were several sociodemographic factors. The study employed logistic regression analysis, and odds ratios (OR) were reported with 95% confidence intervals (CIs) at a significance level of p<0.05 (two-tailed).
Almost two-thirds (69.2%) of respondents had good knowledge of modern contraceptive methods, but only 47.3% practised these methods. Women of nuclear family (adjusted odds ratio (aOR) = 0.60; 95% CI: 0.38,0.95), and who work in agricultural sector (aOR = 0.38; 95% CI: 0.22, 0.64) were less likely to have good knowledge on modern contraceptives. Women with primary (aOR = 2.59; 95% CI: 1.43, 4.72), secondary and above education (aOR = 4.41; 95% CI:2.02,9.63), women with good knowledge of modern contraceptives (aOR = 2.73; 95% CI: 1.66, 4.51), who ever visited a health facility for FP counselling (aOR = 4.40; 95% CI: 2.58, 7.50) had higher odds of modern contraceptives practices.
Muslim women had low use of modern contraceptive methods despite having satisfactory knowledge about them. There is a need for more equitable and focused high-quality FP practices. Targeted interventions are needed to increase the knowledge and practices of contraceptives in the Muslim community. The study highlights the need to target FP interventions among socially disadvantaged women, those living in a nuclear family, and those with poor knowledge of modern contraceptives.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We study the matter creation cosmology as an alternative theory to explain the dark energy phenomena. We discuss the matter-dominated Universe in a flat Friedmann-Robertson-Walker line element by ...adopting the thermodynamics of open systems, in which the matter creation irreversible processes may take place at a cosmological scale. We propose a new form of the matter creation rate,
Γ
=
3
α
H
0
+
3
β
H
+
3
γ
a
¨
a
˙
, which generalizes some of the previous models in the literature. Exact solutions of the field equations are found and discussed the evolution of the Universe. Constraints on the model parameters are obtained from Markov Chain Monte Carlo (MCMC) analysis using the Supernova distance modulus data, observational measurements of Hubble parameter, Baryon acoustic oscillation data. The trajectories of the evolution of the scale factor, deceleration parameter and equation of state parameter are plotted by using best-fit values of the parameters. It is observed that the model shows accelerating behavior and behaves quintessence like (
ω
>
-
1
). The age of the Universe is obtained which is in good agreement with
Λ
CDM model. We examine the model using two independent diagnostic parameters, namely statefinder and
Om
. We apply Akaike information criterion (
AIC
) and Bayesian information criterion (
BIC
) to discriminate the model based on the penalization associated to the number of parameters. The analysis shows that the model has close resemblance to the
Λ
C
D
M
cosmology. We also discuss the thermodynamics of the model and find that the model satisfies the generalized second law of thermodynamics with certain constraints.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this work, we study a flat Friedmann–Robertson–Walker universe filled with dark matter and viscous new holographic dark energy. We present four possible solutions of the model depending on the ...choice of the viscous term. We obtain the evolution of the cosmological quantities such as scale factor, deceleration parameter and transition redshift to observe the effect of viscosity in the evolution. We also emphasis upon the two independent geometrical diagnostics for our model, namely the statefinder and the
Om
diagnostics. In the first case we study new holographic dark energy model without viscous and obtain power-law expansion of the universe which gives constant deceleration parameter and statefinder parameters. In the limit of the parameter, the model approaches to
Λ
C
D
M
model. In new holographic dark energy model with viscous, the bulk viscous coefficient is assumed as
ζ
=
ζ
0
+
ζ
1
H
, where
ζ
0
and
ζ
1
are constants, and
H
is the Hubble parameter. In this model, we obtain all possible solutions with viscous term and analyze the expansion history of the universe. We draw the evolution graphs of the scale factor and deceleration parameter. It is observed that the universe transits from deceleration to acceleration for small values of
ζ
in late time. However, it accelerates very fast from the beginning for large values of
ζ
. By illustrating the evolutionary trajectories in
r
-
s
and
r
-
q
planes, we find that our model behaves as an quintessence like for small values of viscous coefficient and a Chaplygin gas like for large values of bulk viscous coefficient at early stage. However, model has close resemblance to that of the
Λ
C
D
M
cosmology in late time. The
Om
has positive and negative curvatures for phantom and quintessence models, respectively depending on
ζ
. Our study shows that the bulk viscosity plays very important role in the expansion history of the universe.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The severe acute respiratory syndrome coronavirus 2 is spreading like wildfire with no specific recommended treatment in sight. While some risk factors such as the presence of comorbidities, old age, ...and ethnicity have been recognized, not a lot is known about who the virus will strike first or impact more. In this hopeless scenario, exploration of time-tested facts about viral infections, in general, seems to be a sound basis to prop further research upon. The fact that immunity and its various determinants (e.g., micronutrients, sleep, and hygiene) have a crucial role to play in the defense against invading organisms, may be a good starting point for commencing research into these as yet undisclosed territories. Herein, the excellent immunomodulatory, antiviral, and anti-inflammatory roles of Vitamin D necessitate thorough investigation, particularly in COVID-19 perspective. This article reviews mechanisms and evidence suggesting the role Vitamin D plays in people infected by the newly identified COVID-19 virus. For this review, we searched the databases of Medline, PubMed, and Embase. We studied several meta-analyses and randomized controlled trials evaluating the role of Vitamin D in influenza and other contagious viral infections. We also reviewed the circumstantial and anecdotal evidence connecting Vitamin D with COVID-19 emerging recently. Consequently, it seems logical to conclude that the immune-enhancing, antiviral, anti-inflammatory, and lung-protective role of Vitamin D can be potentially lifesaving. Hence, Vitamin D deserves exhaustive exploration through rigorously designed and controlled scientific trials. Using Vitamin D as prophylaxis and/or chemotherapeutic treatment of COVID-19 infection is an approach worth considering. In this regard, mass assessment and subsequent supplementation can be tried, especially considering the mechanistic evidence in respiratory infections, low potential for toxicity, and widespread prevalence of the deficiency of Vitamin D affecting many people worldwide.
Childhood and adolescence require adequate amount of micronutrients for normal growth and development. The primary objective of study was to assess the prevalence of deficiencies of Vitamins (Vitamin ...A, 25 Hydroxy Vitamin D, Vitamin B12 and Folate) and minerals (Calcium, Zinc, Selenium and Iron), among urban school going children aged 6-11 and 12-16 years in ten cities of India. Secondary objective was to find the association between micronutrient deficiencies with sociodemographic and anthropometric indicators.
A multi-center cross-sectional study was conducted across India. Participants in the age groups of 6 to 11 years (group 1) and 12 to 16 years (group 2) were selected from randomly chosen schools from each center. Data on socio economic status, anthropometric measures was collected. Blood samples were collected for biochemical analysis of micronutrients. Point estimates and 95% confidence intervals was used to assess the prevalence of deficiencies. Associations were observed using chi square, student t test and ANOVA test.
From April 2019 to February 2020, 2428 participants (1235 in group 1 and 1193 group 2) were recruited from 60 schools across ten cites. The prevalence of calcium and iron deficiency was 59.9% and 49.4% respectively. 25 Hydroxy Vitamin D deficiency was seen in 39.7% and vitamin B12 in 33.4% of subjects. Folate, Selenium and Zinc were deficient in 22.2%, 10.4% and 6.8% of subjects respectively. Vitamin A deficiency least (1.6%). Anemia was prevalent in 17.6% subjects and was more common among females.
One or more micronutrient deficiencies are found in almost one half of school going children in urban area. Hence efforts must be made to combat these on priority.
CTRI/2019/02/017783.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this paper, we study Friedmann cosmology with time-varying vacuum energy density in the context of Brans–Dicke theory. We consider an isotropic and homogeneous flat space, filled with a ...matter-dominated perfect fluid and a dynamical cosmological term
Λ
(
t
)
, obeying the equation of state of the vacuum. As the exact nature of a possible time-varying vacuum is yet to be found, we explore
Λ
(
t
)
given by the phenomenological law
Λ
(
t
)
=
λ
+
σ
H
, where
λ
and
σ
are positive constants. We solve the model and then focus on two different cases
Λ
H
1
and
Λ
H
2
by assuming
Λ
=
λ
and
Λ
=
σ
H
, respectively. Notice that
Λ
H
1
is the analog of the standard
Λ
CDM, but within the Brans–Dicke cosmology. We find the analytical solution of the main cosmological functions such as the Hubble parameter, the scale factor, deceleration and equation of state parameters for these models. In order to test the viability of the cosmological scenarios, we perform two sets of joint observational analyses of the recent Type Ia supernova data (Pantheon), observational measurements of Hubble parameter data, Baryon acoustic oscillation/Cosmic microwave background data and Local Hubble constant for each model. For the sake of comparison, the same data analysis is performed for the
Λ
CDM model. Each model shows a transition from decelerated phase to accelerated phase and can be viewed as an effective quintessence behavior. Using the model selection criteria AIC and BIC to distinguish from existing dark energy models, we find that the Brans–Dicke analog of the
Λ
-cosmology (i.e. our model
Λ
H
1
) performs at a level comparable to the standard
Λ
CDM, whereas
Λ
H
2
is less favoured.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this paper, we study the adiabatic matter creation process in holographic dark energy (HDE) with the motivation of considering it as an alternative choice to explain the recent accelerating phase ...of the Universe. In the background, we consider a homogeneous and isotropic flat Friedmann-Robertson-Walker geometry. It has been observed that the HDE with Hubble horizon as an IR cutoff does not show an accelerating Universe. Instead of assuming other IR cutoffs in order to have a transition at low redshifts, we consider the HDE model with the gravitationally induced matter creation processes. The matter creation rate is phenomenologically parametrized by a linear combination in terms of Hubble parameter, that is, Γ = 3αH0 + 3βH , where α and β are positive constants. Some particular cases like HDE with Γ = 0 and Γ ∝ H are also studied. The evolution of such models are tested by the latest observational data of a type Ia supernova, observational Hubble data, and latest local H0 by SH0ES. We discuss the evolution of the Universe by plotting the trajectory of cosmological parameters using best-fit values. We find that the HDE model Γ = 3αH0 + 3βH corresponds to early deceleration and then a smooth transition into an accelerated epoch. We discuss the cosmographic parameters and O m to distinguish models with other standard dark energy models. By using the Akaike information criterion and the Bayesian information criterion, we also assess the viability of models corresponding to the Λ CDM model. Finally, we discuss the thermodynamics of HDE model with matter creation and find that the model satisfies the generalized second law of thermodynamic under certain conditions.
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