Cu(I)-catalyzed azide–alkyne 1,3-dipolar cycloaddition (CuAAC), popularly known as the “click reaction”, serves as the most potent and highly dependable tool for facile construction of simple to ...complex architectures at the molecular level. Click-knitted threads of two exclusively different molecular entities have created some really interesting structures for more than 15 years with a broad spectrum of applicability, including in the fascinating fields of synthetic chemistry, medicinal science, biochemistry, pharmacology, material science, and catalysis. The unique properties of the carbohydrate moiety and the advantages of highly chemo- and regioselective click chemistry, such as mild reaction conditions, efficient performance with a wide range of solvents, and compatibility with different functionalities, together produce miraculous neoglycoconjugates and neoglycopolymers with various synthetic, biological, and pharmaceutical applications. In this review we highlight the successful advancement of Cu(I)-catalyzed click chemistry in glycoscience and its applications as well as future scope in different streams of applied sciences.
Polymers derived from plant and animal sources are of great interest in wastewater remediation due to their cost-effectiveness and renewable adsorption capabilities, one such polymer is nanocellulose ...(NC). NC has gained a lot of attention in various research fields due to its abundance in nature, nano-dimension, high surface area, stability and bio-compatibility. As a result, NC has emerged as a great potential adsorbent for the removal of contaminants such as heavy metals, organic dyes, oils, pharmaceutical and etc. in the environmental remediation. This review focuses on the description of the building blocks, structure, properties, isolation and also discusses the potential of nanocellulose based composites materials with reinforcements such as activated carbon, carbon nanotube, graphene oxides, metals, non-metals and ceramics that were effectively used as an adsorbents for diverse organic and inorganic contaminants in water.
Natural kaolin was refluxed with sulphuric acid of different concentrations 1
M, 3
M, 5
M and 10
M at 110
°C for 4
h followed by calcination at 500
°C for 2
h. The physico-chemical characteristics of ...acid-leached kaolinite clay were studied by XRF, XRD, FTIR, TGA, DTA, SEM and N
2 adsorption techniques. XRF and FTIR studies indicate that acid treatment under reflux conditions leads to the removal of the octahedral Al
3+ cations along with other impurities. XRD of 5
M and 10
M treated kaolin shows that treatment with high concentrated acid provoked an amorphization resulting in the formation of an amorphous silica type phase. Leaching of Al
3+ ions increased progressively with severity of the acid treatment. The acid treatment increased the Si/Al ratio from 0.65 to 8.09, surface area from 23
m
2/g to 143
m
2/g and pore volume from 0.361
cc/g to 1.18
cc/g as the acid concentration was increased to 10
M. Solids thus obtained by acid treatments can be used as promising adsorbents and catalyst supports.
Abstract Colloidal nanocarriers, in their various forms, have the possibility of providing endless opportunities in the area of drug delivery. The current communication embodies an in-depth ...discussion of colloidal nanocarriers with respect to formulation aspects, types, and site-specific drug targeting using various forms of colloidal nanocarriers with special insights to the field of oncology. Specialized nanotechnological approaches like quantum dots, dendrimers, integrins, monoclonal antibodies, and so forth, which have been extensively researched for targeted delivery of therapeutic and diagnostic agents, are also discussed. Nanotechnological patents, issued by the U.S. Patent and Trademark Office in the area of drug delivery, are also included in this review to emphasize the importance of nanotechnology in the current research scenario. From the Clinical Editor Colloidal nanocarriers provide almost endless opportunities in the area of drug delivery. While the review mainly addresses potential oncological applications, similar approaches may be applicable in other conditions with a requirement for targeted drug delivery. Technologies including quantum dots, dendrimers, integrins, monoclonal antibodies are discussed, along with US-based patents related to these methods.
The therapeutic areas of infectious diseases and oncology have benefited from abundant scaffold diversity in natural products, able to interact with many specific targets within the cell and indeed ...for many years have been source or inspiration for the majority of FDA approved drugs. The present review describes natural products (NPs), semi-synthetic NPs and NP-derived compounds that have undergone clinical evaluation or registration from 2005 to 2010 by disease area i.e. infectious (bacterial, fungal, parasitic and viral), immunological, cardiovascular, neurological, inflammatory and related diseases and oncology.
Natural products have long been an excellent souces or inspiration for the drug development. This review describes natural and NP-derived compounds that have undergone clinical evaluation since past five years.
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► Medicinal plants have long been an excellent source of pharmaceutical agents. ► NP scaffolds are infact key in optimizing chemical diversity for human use. ► This review deals the clinical evaluation of 232 NP or their inspired drug candidates.
Fluoride in drinking water has a profound effect on teeth and bones. Up to a small level (1–1.5
mg/L) this strengthens the enamel. Concentrations in the range of 1.5–4
mg/L result in dental fluorosis ...whereas with prolonged exposure at still higher fluoride concentrations (4–10
mg/L) dental fluorosis progresses to skeletal fluorosis. High fluoride concentrations in groundwater, up to more than 30
mg/L, occur widely, in many parts of the world. This review article is aimed at providing precise information on efforts made by various researchers in the field of fluoride removal for drinking water. The fluoride removal has been broadly divided in two sections dealing with membrane and adsorption techniques. Under the membrane techniques reverse osmosis, nanofiltration, dialysis and electro-dialysis have been discussed. Adsorption, which is a conventional technique, deals with adsorbents such as: alumina/aluminium based materials, clays and soils, calcium based minerals, synthetic compounds and carbon based materials. Studies on fluoride removal from aqueous solutions using various reversed zeolites, modified zeolites and ion exchange resins based on cross-linked polystyrene are reviewed. During the last few years, layered double oxides have been of interest as adsorbents for fluoride removal. Such recent developments have been briefly discussed.
•Iron oxide–alumina nanocomposite fibers were prepared by electrospinning method.•Pure crystalline ultra-fine fibers were obtained after sintering at 1000°C.•The nanocomposite fibers are efficient ...adsorbent for removal of heavy metal ions.•The removal percentage was in the order of Cu2+<Pb2+<Ni2+<Hg2+.•Maximum 90% removal of Hg2+ ions were observed by mixed oxide nanocomposite fibers.
In this study, Iron oxide–alumina mixed nanocomposite fiber was prepared by electrospinning method and its performance was evaluated as a heavy metal ion adsorbent. Here boehmite nanoparticle was synthesized by sol–gel method and was impregnated in PVP-iron acetylacetonate solution in a ratio of 1:1:2. These boehmite impregnated polymer solution was electrospun to form nanocomposite polymer fiber. The electrospun nanofiber was sintered at 1000°C for converting it to pure oxide form for further application as adsorbent. Iron oxide–alumina mixed nanocomposite fiber was characterized by UV–vis-DRS, IR, SEM–EDX, TEM, BET and TGA–DTA analytical techniques. Batch adsorption experiments were carried out to study the sorption behavior of Cu2+, Pb2+, Ni2+ and Hg2+ ions as a function of initial concentration, contact time and pH. The removal percentage was in the order of Cu2+<Pb2+<Ni2+<Hg2+. The maximum sorption capacities by applying the Langmuir equation were found to be 4.98mg/g for Cu2+, 32.36mg/g for Ni2+, 23.75mg/g for Pb2+ and 63.69mg/g for Hg2+ ions. The regeneration studies of mixed nanocomposite adsorbents were also reported here.
We have investigated the accelerating behaviour of the Universe in
f
(
Q
,
T
) gravity in an isotropic and homogeneous space-time. We have initially derive the dynamical parameters in the general ...form of
f
(
Q
,
T
)
=
α
Q
m
+
β
T
(Xu et al. in Eur Phys J C 79:708, 2019) and then split it into two cases (i) one with
m
=
1
and the (ii) other with
β
=
0
. In the first case, it reduces to the linear form of the functional
f
(
Q
,
T
) and second case leads to the higher power of the nonmetricity
Q
. In an assumed form of the hyperbolic scale factor, the models are constructed and its evolutionary behaviours are studied. The geometrical parameters as well the equation of state parameter are obtained and found to be in the preferred range of the cosmological observations. Marginal variation has been noticed in the behaviour of
ω
and
ω
eff
at present time. The violation of strong energy conditions in both the cases are shown. The dynamical system analysis for the models has been performed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The objective of this study was to calculate the extent and decay of linkage disequilibrium (LD) in 96 crossbred Vrindavani cattle genotyped with Bovine SNP50K Bead Chip. After filtering, 43,821 SNPs ...were retained for final analysis, across 2500.3 Mb of autosome. A significant percentage of SNPs was having minor allele frequency of less than 0.20. The extent of LD between autosomal SNPs up to 10 Mb apart across the genome was measured using r2 statistic. The mean r2 value was 0.43, if pairwise distance of marker was less than10 kb and it decreased further to 0.21 for 25-50 kb markers distance. Further, the effect of minor allele frequency and sample size on LD estimate was investigated. The LD value decreased with the increase in inter-marker distance, and increased with the increase of minor allelic frequency. The estimated inbreeding coefficient and effective population size were 0.04, and 46 for present generation, which indicated small and unstable population of Vrindavani cattle. These findings suggested that a denser or breed specific SNP panel would be required to cover all genome of Vrindavani cattle for genome wide association studies (GWAS).
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this paper, we have shown the matter bounce scenario of the Universe in an extended symmetric teleparallel gravity, the
f
(
Q
) gravity. Motivated from the bouncing scenario and loop quantum ...cosmology (LQC), the form of the function
f
(
Q
) has been obtained at the backdrop of Friedmann–Lema
i
^
tre–Robertson Walker (FLRW) space time. Considering the background cosmology dominated by dust fluid, the e-folding parameter has been expressed, which contains the nonmetricity term. Since the slow roll criterion in the bouncing context is not valid, we used a conformal equivalence between
f
(
Q
) and scalar-tensor model to apply the bottom-up reconstruction technique in the bouncing model. The dynamics of the model has been studied through the phase space analysis, where both the stable and unstable nodes are obtained. Also, the stability analysis has been performed with the first order scalar perturbation of the Hubble parameter and matter energy density to verify the stability of the model.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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