In this paper, we investigate the dark energy phenomenon by studying the Tsallis holographic dark energy within the framework of Brans–Dicke (BD) scalar–tensor theory of gravity (Brans and Dicke in ...Phys. Rev. 124:925, 1961). In this context, we choose the BD scalar field
ϕ
as a logarithmic function of the average scale factor
a
(
t
) and Hubble horizon as the IR cutoff (
L
=
H
-
1
). We reconstruct two cases of non-interacting and interacting fluid (dark sectors of cosmos) scenario. The physical behavior of the models are discussed with the help of graphical representation to explore the accelerated expansion of the universe. Moreover, the stability of the models are checked through squared sound speed
v
s
2
. The well-known cosmological plane i.e.,
ω
de
-
ω
de
′
is constructed for our models. We also include comparison of our findings of these dynamical parameters with observational constraints. It is also quite interesting to mention here that the results of deceleration, equation of state parameters and
ω
de
-
ω
de
′
plane coincide with the modern observational data.
An in situ modified Hummers method (without the use of any surfactants) has been used for the deposition of bismuth (Bi) nanoparticles onto the surface of reduced graphene oxide (RGO) sheets. The ...as-synthesized nanocomposites were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, transmission electron microscopy (TEM), thermogravimetry (TG) and differential scanning calorimetry (DSC). The morphology of the RGO/Bi nanocomposites provides a better choice as an electrode material for detection of heavy metal ions due to its better functional properties over the Bi film electrode. Trace analysis of heavy metal ions like Cd+2, Pb+2, Cu+2 and Zn+2 in water is carried out by stripping voltammetric analysis using RGO/Bi nanocomposite as an electrode material. The sensitivity and detection limit of the electrode were quantitatively estimated from the analysis. The three sigma detection limits at different deposition potential for Cd2+, Pb2+, Zn2+ and Cu2+ were obtained as 2.8, 0.55, 17 and 26μgL−1, respectively. Copper detection using Bi-film electrode was a major challenge, which has been resolved using the RGO/Bi nanocomposite electrode.
► RGO/Bi nanocomposite synthesized by modified Hummers method without surfactant. ► Reduction of GO and formation of Bi nanoparticles are accomplished simultaneously. ► Trace analysis of heavy ions with composite as electrode by stripping voltammetry. ► Detection limit for Cd2+, Pb2+, Zn2+, Cu2+ were 2.8, 0.55, 17 and 26μgL−1. ► Copper detection using Bi-film electrode resolved using these composites.
Axons extend for tremendously long distances from the neuronal soma and make use of localized mRNA translation to rapidly respond to different extracellular stimuli and physiological states. The ...locally synthesized proteins support many different functions in both developing and mature axons, raising questions about the mechanisms by which local translation is organized to ensure the appropriate responses to specific stimuli. Publications over the past few years have uncovered new mechanisms for regulating the axonal transport and localized translation of mRNAs, with several of these pathways converging on the regulation of cohorts of functionally related mRNAs - known as RNA regulons - that drive axon growth, axon guidance, injury responses, axon survival and even axonal mitochondrial function. Recent advances point to these different regulatory pathways as organizing platforms that allow the axon's proteome to be modulated to meet its physiological needs.
Metazoans are likely to have their roots in the Cryogenian period, but there is a marked increase in the appearance of novel animal and algae fossils shortly after the termination of the late ...Cryogenian (Marinoan) glaciation about 635 million years ago. It has been suggested that an oxygenation event in the wake of the severe Marinoan glaciation was the driving factor behind this early diversification of metazoans and the shift in ecosystem complexity. But there is little evidence for an increase in oceanic or atmospheric oxygen following the Marinoan glaciation, or for a direct link between early animal evolution and redox conditions in general. Models linking trends in early biological evolution to shifts in Earth system processes thus remain controversial. Here we report geochemical data from early Ediacaran organic-rich black shales (∼635-630 million years old) of the basal Doushantuo Formation in South China. High enrichments of molybdenum and vanadium and low pyrite sulphur isotope values (Δ(34)S values ≥65 per mil) in these shales record expansion of the oceanic inventory of redox-sensitive metals and the growth of the marine sulphate reservoir in response to a widely oxygenated ocean. The data provide evidence for an early Ediacaran oxygenation event, which pre-dates the previous estimates for post-Marinoan oxygenation by more than 50 million years. Our findings seem to support a link between the most severe glaciations in Earth's history, the oxygenation of the Earth's surface environments, and the earliest diversification of animals.
The ocean‐atmosphere system is typically envisioned to have gone through a unidirectional oxygenation with significant oxygen increases in the earliest (ca. 635 Ma), middle (ca. 580 Ma), or late (ca. ...560 Ma) Ediacaran Period. However, temporally discontinuous geochemical data and the patchy metazoan fossil record have been inadequate to chart the details of Ediacaran ocean oxygenation, raising fundamental debates about the timing of ocean oxygenation, its purported unidirectional rise, and its causal relationship, if any, with the evolution of early animal life. To better understand the Ediacaran ocean redox evolution, we have conducted a multi‐proxy paleoredox study of a relatively continuous, deep‐water section in South China that was paleogeographically connected with the open ocean. Iron speciation and pyrite morphology indicate locally euxinic (anoxic and sulfidic) environments throughout the Ediacaran in this section. In the same rocks, redox sensitive element enrichments and sulfur isotope data provide evidence for multiple oceanic oxygenation events (OOEs) in a predominantly anoxic global Ediacaran–early Cambrian ocean. This dynamic redox landscape contrasts with a recent view of a redox‐static Ediacaran ocean without significant change in oxygen content. The duration of the Ediacaran OOEs may be comparable to those of the oceanic anoxic events (OAEs) in otherwise well‐oxygenated Phanerozoic oceans. Anoxic events caused mass extinctions followed by fast recovery in biologically diversified Phanerozoic oceans. In contrast, oxygenation events in otherwise ecologically monotonous anoxic Ediacaran–early Cambrian oceans may have stimulated biotic innovations followed by prolonged evolutionary stasis.
The role of skeletal muscle in nonshivering thermogenesis (NST) is not well understood. Here we show that sarcolipin (Sln), a newly identified regulator of the sarco/endoplasmic reticulum ...Ca(2+)-ATPase (Serca) pump, is necessary for muscle-based thermogenesis. When challenged to acute cold (4 °C), Sln(-/-) mice were not able to maintain their core body temperature (37 °C) and developed hypothermia. Surgical ablation of brown adipose tissue and functional knockdown of Ucp1 allowed us to highlight the role of muscle in NST. Overexpression of Sln in the Sln-null background fully restored muscle-based thermogenesis, suggesting that Sln is the basis for Serca-mediated heat production. We show that ryanodine receptor 1 (Ryr1)-mediated Ca(2+) leak is an important mechanism for Serca-activated heat generation. Here we present data to suggest that Sln can continue to interact with Serca in the presence of Ca(2+), which can promote uncoupling of the Serca pump and cause futile cycling. We further show that loss of Sln predisposes mice to diet-induced obesity, which suggests that Sln-mediated NST is recruited during metabolic overload. These data collectively suggest that SLN is an important mediator of muscle thermogenesis and whole-body energy metabolism.
Multimorbidity, the concurrent presence of two or more chronic conditions is an emerging public health challenge. Till date, most of the research have focused on the presence and interaction of ...selected co-morbidities in tuberculosis (TB). There exist a critical knowledge gap on the magnitude of multimorbidity among TB patients and its impact on health outcomes.
We undertook a cross-sectional study to assess the prevalence and patterns of multimorbidity among newly diagnosed TB patients in two states of India. A total of 323 patients were interviewed using a structured multimorbidity assessment questionnaire for primary care (MAQ-PC). MAQ-PC is already validated for Indian population and elicits 22 chronic conditions. We defined TB multimorbidity as the co-existence of TB with one or more chronic conditions and identified commonly occurring dyads (TB + single condition) and triads (TB + two conditions).
More than half (52%) of TB patients reported multimorbidity. Among dyads, depression, diabetes mellitus (DM), acid peptic disease (APD), hypertension, chronic alcoholism, arthritis and chronic back ache (CBA) were the most common co-occurring conditions while 'DM + arthritis', 'depression + APD', 'depression + DM' were the most commonly occurring triads among TB patients. Factors such as increasing age, low levels of education, alcohol abusers, drug-resistant TB and having health insurance were significantly associated with multimorbidity among TB patients.
Our findings suggest high prevalence of multimorbidity among newly diagnosed TB patients in India. The presence of concordant and discordant conditions with TB may increase the health complexity, thus necessitating appropriate care protocols. Given, the current situation, wherein TB and non-communicable diseases (NCD) services are delivered through collaborative framework between programmes, there is a need for addressing multimorbidity at the healthcare delivery level.
Elemental Mg and Mg-alloy (AZ91D) based composites reinforced with 15
vol.% silicon carbide (SiC) particulates (average particle size 15
μm and 150
μm) were synthesised by stir casting technique. ...Particle distribution, particle–matrix interfacial reaction, hardness and mechanical properties in the as cast as well as T4 heat-treated conditions were investigated. The composite materials show uniform distribution of SiC particulates. The average grain size decreases with the presence of SiC particulates and the grain size further decreases as the particle size decreases. The AZ91D alloy composite shows an increase in hardness and elastic modulus compared to monolithic alloys. The improvement in elastic modulus of composite containing 15
μm size SiC particles is significantly higher than the composite with 150
μm size particles. The ultimate tensile strength and ductility of composite materials were reduced compared to unreinforced alloy.
We demonstrate that the pulsed-time structure and high-peak ion intensity provided by the laser-ablation process can be directly combined with the high resolution, high efficiency, and low background ...offered by collinear resonance ionization spectroscopy. This simple, versatile, and powerful method offers new and unique opportunities for high-precision studies of atomic and molecular structures, impacting fundamental and applied physics research. We show that even for ion beams possessing a relatively large energy spread, high-resolution hyperfine-structure measurements can be achieved by correcting the observed line shapes with the time-of-flight information of the resonantly ionized ions. This approach offers exceptional advantages for performing precision measurements on beams with large energy spreads and allows measurements of atomic parameters of previously inaccessible electronic states. The potential of this experimental method in multidisciplinary research is illustrated by performing, for the first time, hyperfine-structure measurements of selected states in the naturally occurring isotopes of indium,In113,115. Ab initio atomic-physics calculations have been performed to highlight the importance of our findings in the development of state-of-the-art atomic many-body methods, nuclear structure, and fundamental-physics studies.
We have developed a novel water-dispersible oleic acid (OA)-Pluronic-coated iron oxide magnetic nanoparticle formulation that can be loaded easily with high doses of water-insoluble anticancer ...agents. Drug partitions into the OA shell surrounding iron oxide nanoparticles, and the Pluronic that anchors at the OA−water interface confers aqueous dispersity to the formulation. Neither the formulation components nor the drug loading affected the magnetic properties of the core iron oxide nanoparticles. Sustained release of the incorporated drug is observed over 2 weeks under in vitro conditions. The nanoparticles further demonstrated sustained intracellular drug retention relative to drug in solution and a dose-dependent antiproliferative effect in breast and prostate cancer cell lines. This nanoparticle formulation can be used as a universal drug carrier system for systemic administration of water-insoluble drugs while simultaneously allowing magnetic targeting and/or imaging. Keywords: Sustained release; water-insoluble drugs; cellular uptake; breast cancer; targeting; tumor therapy; magnetic nanoparticles
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