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1.
Inorg Chem ; 62(11): 4417-4434, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36883826

RESUMO

Seven new inorganic-organic coordination polymer compounds have been synthesized and their structures are determined by single-crystal structure determination. The compounds were prepared by the sequential assembly of a [Cu6(mna)6]6- moiety in the presence of a Mn salt and a secondary amine ligand. Of the seven compounds, [{Cu6(mna)6}Mn3(H2O)(H2O)1.5]·5.5H2O (I), [{Cu6(mna)6}Mn3(H2O)(Im)1.5]·3.5H2O (Ia), [{Cu6(mna)6}{Mn(BPY)(H2O)}2{Mn(H2O)4}]·2H2O (III), and [{Cu6(mna)6}{Mn(BPE)0.5(H2O)2}2{Mn(BPE)(H2O)2}] (IV) have a three-dimensional structure, whereas [{Cu6(mna)4.5(Hmna)1.5}{Mn(BPA)(H2O)2}{Mn(H2O)}]{Mn0.25(H2O)3}·7H2O (II), [{Cu6(mna)6}{Mn(4-BPDB)0.5H2O}{Mn(H2O)2}].{Mn(H2O)6}·6H2O (V), and [{Cu6(mna)4(Hmna)2}·{Mn(H2O)3}2]·(4-APY)2·6H2O (VI) have a two-dimensional structure. Some of the prepared compounds exhibit structures that closely resemble the classical inorganic structures, such as NaCl (Ia, III), NiAs (I), and CdI2 (IV and VI). The stabilization of such simple structures from the assembly of octahedral Cu6S6 clusters and different Mn species and aromatic nitrogen-containing ligands suggests the subtle interplay between the constituent reactants. The compounds were examined for the multicomponent Hantzsch reaction, which gave the product in good yields. The compounds, II and VI, on heating to 70 °C change color reversibly from pale yellow to deep red, which suggests the possible use of these compounds as thermochromic materials. The present study suggests that the Cu6S6 octahedral clusters can be assembled into structures that resemble classical inorganic structures.

2.
Inorg Chem ; 62(28): 11142-11151, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37393542

RESUMO

Multistep cascade reactions are important to achieve atom as well as step economy over conventional synthesis. This approach, however, is limited due to the incompatibility of the available reactive centers in a catalyst. In the present study, new MOF compounds, [Zn2(SDBA)(3-ATZ)2]·solvent, I and II, with tetrahedral Zn centers as good Lewis acidic sites and the free amino group of the 3-amino triazole ligand as a strong Lewis base center were shown to perform 4-step cascade/tandem reaction in a facile manner. Effective conversion of benzaldehyde dimethyl acetal in the presence of excess nitromethane at 100 °C in water to 1-(1,3-dinitropropan-2-yl) benzene was achieved in 10 h with yields of ∼95% (I) and ∼94% (II). This 4-step cascade reaction proceeds via deacetalization (Lewis acid), Henry (Lewis base), and Michael (Lewis base) reactions. The present work highlights the importance of spatially separated functional groups in multistep tandem catalysis─the examples of which are not common.

4.
Environ Toxicol ; 30(2): 177-87, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23804459

RESUMO

This paper presents an evaluation of the genotoxic effects of cadmium chloride (CdCl2 ) on marine gastropod, Nerita chamaeleon following the technique of comet assay and the DNA alkaline unwinding assay (DAUA). In this study, the extent of DNA damage in gill cells of N. chamaeleon was measured after in vivo exposure to four different concentrations (10, 25, 50, and 75 µg/L) of CdCl2 . In vitro exposure of hydrogen peroxide (H2 O2 ; 1, 10, 25, and 50 µM) of the gill cells showed a significant increase in the percentage tail DNA, Olive tail moment, and tail length (TL). Significant changes in percentage tail DNA by CdCl2 exposure were observed in all exposed groups of snails with respect to those in control. Exposure to 75 µg/L of CdCl2 produced significant decrease in DNA integrity as measured by DAUA at all duration with respect to control. In vivo exposure to different concentrations of CdCl2 (10, 25, 50, and 75 µg/L) to N. chamaeleon showed considerable increase in DNA damage as observed by both alkaline comet assay and the DAUA. The extent of DNA damage in marine gastropods determined by the application of alkaline comet assay and DAUA clearly indicated the genotoxic responses of marine gastropod, N. chamaeleon to a wide range of cadmium concentration in the marine environment.


Assuntos
Cloreto de Cádmio/toxicidade , Gastrópodes/genética , Mutagênicos/toxicidade , Animais , Separação Celular , Ensaio Cometa , DNA/genética , Dano ao DNA , Brânquias/citologia , Brânquias/efeitos dos fármacos , Brânquias/metabolismo , Peróxido de Hidrogênio/farmacologia , Testes de Mutagenicidade , Oxidantes/farmacologia , Água do Mar
5.
Oxf Med Case Reports ; 2021(11-12): omab111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34987848

RESUMO

Ring chromosome X is one of the rarest with some unique phenotypical features in Turner syndrome. A young female presented to us with anasarca developed over the past 2 months due to congestive cardiac failure along with jaundice and orthopnea. She had growth retardation, intellectual disability, primary amenorrhea, lack of secondary sexual character development and dysmorphic features like low posterior hairline, shield chest and cubitus valgus. She had dilated cardiomyopathy (DCM) with intracardiac thrombus on echocardiography. Skeletal survey revealed short fourth metacarpal/tarsal on limbs. Karyotyping showed a mosaic pattern, with 45, X/46, X,r(X)(p22.3q28), i.e. Turner syndrome karyotype with ring chromosome. Her heart failure with reduced ejection fraction was managed with vasopressor along with anticoagulant and given oral contraceptive pills for hormone replacement therapy. The ring chromosomal pattern of karyotype in this patient and DCM is a rare cardiological phenomenon that can be associated with Turner syndrome, making this case a unique one.

6.
Sci Rep ; 11(1): 11551, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34078984

RESUMO

Quantum walk has been regarded as a primitive to universal quantum computation. In this paper, we demonstrate the realization of the universal set of quantum gates on two- and three-qubit systems by using the operations required to describe the single particle discrete-time quantum walk on a position space. The idea is to utilize the effective Hilbert space of the single qubit and the position space on which it evolves in order to realize multi-qubit states and universal set of quantum gates on them. Realization of many non-trivial gates and engineering arbitrary states is simpler in the proposed quantum walk model when compared to the circuit based model of computation. We will also discuss the scalability of the model and some propositions for using lesser number of qubits in realizing larger qubit systems.

7.
Sci Rep ; 9(1): 12323, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31444408

RESUMO

We present a scheme for multi-bit quantum random number generation using a single qubit discrete-time quantum walk in one-dimensional space. Irrespective of the initial state of the qubit, quantum interference and entanglement of particle with the position space in the walk dynamics certifies high randomness in the system. Quantum walk in a position space of dimension 2l + 1 ensures string of (l + 2)-bits of random numbers from a single measurement. Bit commitment with the position space and control over the spread of the probability distribution in position space enable us with options to extract multi-bit random numbers. This highlights the power of one qubit, its practical importance in generating multi-bit string in single measurement and the role it can play in quantum communication and cryptographic protocols. This can be further extended with quantum walks in higher dimensions.

9.
Water Res ; 40(17): 3304-12, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16934850

RESUMO

Marine pollutants in relation to planktonic and benthic organisms were examined at two locations along Karnataka coast, one at Kulai (74 degrees 47.74''E and 12 degrees 55.16''N) receiving huge amount of industrial effluents from fertilizer, petroleum and chemical plants along with the sewage discharges. The other site Padubidri (74 degrees 45''E and 13 degrees 10''N) is located 20 km away, which is a typically agricultural and fishing village having no stress of industrial discharges. Although the concentrations of dissolved oxygen (DO), nutrients and trace metals in water and sediment showed marginal differences at these two locations, the concentration of petroleum hydrocarbon (PHC) remained exceptionally high with a maximum of 1523 microg/l at Kulai which is 10 times higher than that at Padubidri (144 microg/l). Biomass and population of phytoplankton and zooplankton showed that the seasonal differences were more conspicuous rather than the regional changes. Macro and meiobenthic population remained high at both the locations during the two seasons. Phytoplankton species indicated that centric diatoms such as Rhizosolenia, Leptocylindricus, Chaetoceros, Thalassiosira and Coscinodiscus contributed to > 90% of population in May and > 70% in January at Kulai. While mixed population of centric, pennate, cyanophycean and dinoflagellates prevailed at Padubidri in January. Lower species diversity and richness accompanied with dominance of fast growing centric diatoms over pennates observed at Kulai act as an index for detection of organic pollution and nutrient enrichment. Similarly, proliferation of benthic bivalves > 54% at Kulai relative to Padubidri suggests that these organisms could sustain organic and industrial pollutants. The results suggest that although Kulai receives large quantities of industrial and sewage effluents responsible for alteration of the ecosystem structure, the excellent wind-driven mixing and tidal flushing keep the waters well aerated thus reducing the severe pollution stress by dispersing the organic and other pollutants. Direct relationship of PHC with Cd and Pb as contaminants, NO3 and PO4 as oxidants of excess PHC and species diversity as promoters of phytoplankton (centric diatoms) and benthic bivalves shown by multiple regression analysis further suggest that these biological parameters could serve as indicators for detecting moderately high environmental stress at Kulai, compared to Padubidri.


Assuntos
Diatomáceas/isolamento & purificação , Monitoramento Ambiental/métodos , Poluentes da Água/análise , Diatomáceas/classificação , Índia , Especificidade da Espécie
10.
PLoS One ; 11(10): e0164718, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27755601

RESUMO

BACKGROUND: Postpartum heammorrhage (PPH), defined as blood loss greater than or equal to 500 ml within 24 hours after birth, is the leading cause of maternal deaths globally and in India. Misoprostol is an important option for PPH management in setting where oxytocin (the gold standard for PPH prevention and treatment) in not available or not feasible to use. For the substantial number of deliveries which take place at home or at lower level heatlh facilities in India, misoprostol pills can be adminstered to prevent PPH. The standard approach using misoprostol is to administer it prophylactically as primary prevention (600 mcg). An alternative strategy could be to administer misoprostol only to those who are at high risk of having PPH i.e. as secondary prevention. METHODS: This study reports on the relative cost per person of a strategy involving primary versus secondary prevention of PPH using misoprostol. It is based on a randomized cluster trial that was conducted in Bijapur district in Karnataka, India between December 2011 and March 2014 among pregnant women to compare two community-level strategies for the prevention of PPH: primary and secondary. The analysis was conducted from the government perspective using an ingredient approach. RESULTS: The cluster trial showed that there were no significant differences in clinical outcomes between the two study arms. However, the results of the cost analysis show that there is a difference of INR 6 (US$ 0.1) per birth for implementing the strategies primary versus secondary prevention. In India where 14.9 million births take place at sub-centres and at home, this additional cost of INR 6 per birth translates to an additional cost of INR 94 (US$ 1.6) million to the government to implement the primary prevention compared to the secondary prevention strategy. CONCLUSION: As clinical outcomes did not differ significantly between the two arms in the trial, taking into account the difference in costs and potential issues with sustainability, secondary prevention might be a more strategic option.


Assuntos
Misoprostol/uso terapêutico , Ocitócicos/uso terapêutico , Hemorragia Pós-Parto/prevenção & controle , Prevenção Primária/economia , Prevenção Secundária/economia , Adulto , Análise Custo-Benefício , Feminino , Humanos , Índia , Parto , Período Pós-Parto , Gravidez
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