ANALYTICAL METHOD DEVELOPMENT AND VALIDATION OF AMLODIPINE IN HUMAN PLASMA USING LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY/MASS SPECTROMETRY

Objective: The objective of the present investigation was to develop a novel, simple, and economic method for the estimation of amlodipine in positive ion mode in human plasma using amlodipine maleate d4 as an internal standard.Methods: The chromatographic separation was performed on Zorbax SB, C18, 50 mm*4.6 mm, and 3.5 mm. The mobile phase was prepared with a mixture of 5 mm ammonium acetate in 0.1% formic acid: High performance liquid chromatographic (HPLC) grade methanol:HPLC grade acetonitrile (40:30:30) that run isocratically at the flow rate of 0.700 ml/min and run time at 2.50 min.Results: The analytical method is valid for the estimation of amlodipine, in human plasma over a range of 0.100 ng/ml–9.990 ng/ml with the detection of amlodipine m/z - 409.10 (parent) and 238.00 (product), and internal standard Amlodipine Maleate d4 m/z - 413.20 (parent), and 238.00 (product) in positive ion mode. The results of carryover test, matrix effect, linearity, precision and accuracy, stabilities, dilution integrity, and run size evaluation test presented in this report are within the acceptance range.Conclusion: A sensitive method for the separation and determination of amlodipine in plasma has been developed based on solid-phase extraction with disposable extraction cartridges in combination with LC and mass spectrophotometers (MS/MS)

Elastic scattering of electrons and positrons from In-115 atoms over the energy range 1 eV-0.5 GeV

We present a theoretical study on the calculations of various cross sections related to the scattering of electrons and positrons from indium atoms. Our calculations cover the energy range 1 eV <= E-i <= 0.5 GeV. We have employed two approaches, applicable for two domains of energy, based on the Dirac partial-wave analysis. In one approach, we have used both the atomic and nuclear potentials to calculate the cross sections for the low and intermediate energies. The other approach, valid for the high-energy scattering, utilizes only the nuclear potential for the phase-shift analysis, and considers the magnetic scattering from the nucleus too. We report the calculations of differential, integral, momentum-transfer and viscosity cross sections along with the spin asymmetries for the elastic scattering of electrons and positrons. Moreover, we have analyzed the critical minima in the elastic differential cross sections, and also computed the absorption and total cross sections. Our results agree reasonably with the available experimental data and other calculations

Carbohydrate restriction for glycemic control in Type 2 diabetes : a systematic review and meta-analysis

Aim To conduct a systematic review and meta‐analysis to evaluate the effect of carbohydrate restriction on glycaemic control in Type 2 diabetes. Methods We searched Medline, EMBASE and CINAHL for the period between 1976 and April 2018. We included randomized controlled trials comparing carbohydrate restriction with a control diet which aimed to maintain or increase carbohydrate intake, and that reported HbA1c as an outcome and reported the amount of carbohydrate consumed during or at the end of the study, with outcomes reported at ≥3 months. Results We identified 1402 randomized controlled trials, 25 of which met the inclusion criteria, incorporating 2132 participants for the main outcome. Definitions of low carbohydrate varied among the studies. The pooled effect estimate from meta‐analysis was a weighted mean difference of –0.09% [95% CI –0.27, 0.08 (P = 0.30); I2 72% (P <0.001)], suggesting no effect on HbA1c of restricting the quantity of carbohydrate. A subgroup analysis of diets containing 50–130 g carbohydrate resulted in a pooled effect estimate of –0.49% [95% CI –0.75, –0.23 (P <0.001); I2 0% (P = 0.56)], suggesting a clinically and statistically significant effect on HbA1c in favour of low‐carbohydrate diets in studies of ≤6 months’ duration. Conclusions There was no overall pooled effect on HbA1c in favour of restricting carbohydrate; however, restriction of carbohydrate to 50–130 g per day had beneficial effects on HbA1c in trials up to 6 months. Future randomized controlled trials should be of >12 months’ duration, assess pre‐study carbohydrate intake, use recognized definitions of low‐carbohydrate diets and examine reasons for non‐concordance in greater detail

A novel hybrid password authentication scheme based on text and image

Considering the popularity and wide deployment of text passwords, we predict that they will be used as a prevalent authentication mechanism for many years to come. Thus, we have carried out studies on mechanisms to enhance text passwords. These studies suggest that password space and memorability should be improved, with an additional mechanism based on images. The combination of text and images increases resistance to some password attacks, such as brute force and observing attacks. We propose a hybrid authentication scheme integrating text and recognition-based graphical passwords. This authentication scheme can reduce the phishing attacks because if users are deceived to share their key passwords, there is still a chance to save the complete password as attackers do not know the users' image preferences. In addition to the security aspect, the proposed authentication scheme increases memorability as it does not require users to remember long and complex passwords. Thus, with the proposed scheme users will be able to create strong passwords without sacrificing usability. The hybrid scheme also offers an enjoyable sign-in/log-in experience to users

A unique bacteriohopanetetrol stereoisomer of marine anammox

Anaerobic ammonium oxidation (anammox) is a major process of bioavailable nitrogen removal from marine systems. Previously, a bacteriohopanetetrol (BHT) isomer, with unknown stereochemistry, eluting later than BHT using high performance liquid chromatography (HPLC), was detected in ‘Ca. Scalindua profunda’ and proposed as a biomarker for anammox in marine paleo-environments. However, the utility of this BHT isomer as an anammox biomarker is hindered by the fact that four other, non-anammox bacteria are also known to produce a late-eluting BHT stereoisomer. The stereochemistry in Acetobacter pasteurianus, Komagataeibacter xylinus and Frankia sp. was known to be 17β, 21β(H), 22R, 32R, 33R, 34R (BHT-34R). The stereochemistry of the late-eluting BHT in Methylocella palustris was unknown. To determine if marine anammox bacteria produce a unique BHT isomer, we studied the BHT distributions and stereochemistry of known BHT isomer producers and of previously unscreened marine (‘Ca. Scalindua brodeae’) and freshwater (‘Ca. Brocadia sp.’) anammox bacteria using HPLC and gas chromatographic (GC) analysis of acetylated BHTs and ultra high performance liquid chromatography (UHPLC)-high resolution mass spectrometry (HRMS) analysis of non-acetylated BHTs. The 34R stereochemistry was confirmed for the BHT isomers in Ca. Brocadia sp. and Methylocella palustris. However, ‘Ca. Scalindua sp.’ synthesise a stereochemically distinct BHT isomer, with still unconfirmed stereochemistry (BHT-x). Only GC analysis of acetylated BHT and UHPLC analysis of non-acetylated BHT distinguished between late-eluting BHT isomers. Acetylated BHT-x and BHT-34R co-elute by HPLC. As BHT-x is currently only known to be produced by ‘Ca. Scalindua spp.’, it may be a biomarker for marine anammox

Asymmetric Fermi superfluid in a harmonic trap

We consider a dilute two-component atomic fermion gas with unequal populations in a harmonic trap potential using the mean field theory and the local density approximation. We show that the system is phase separated into concentric shells with the superfluid in the core surrounded by the normal fermion gas in both the weak-coupling BCS side and near the Feshbach resonance. In the strong-coupling BEC side, the composite bosons and left-over fermions can be mixed. We calculate the cloud radii and compare axial density profiles systemically for the BCS, near resonance and BEC regimes.Comment: 15 pages, 5 figure

Effect of microstructural evolution on magnetic properties of Ni thin films

Copyright © Indian Academy of Sciences.The magnetic properties of Ni thin films, in the range 20–500 nm, at the crystalline-nanocrystalline interface are reported. The effect of thickness, substrate and substrate temperature has been studied. For the films deposited at ambient temperatures on borosilicate glass substrates, the crystallite size, coercive field and magnetization energy density first increase and achieve a maximum at a critical value of thickness and decrease thereafter. At a thickness of 50 nm, the films deposited at ambient temperature onto borosilicate glass, MgO and silicon do not exhibit long-range order but are magnetic as is evident from the non-zero coercive field and magnetization energy. Phase contrast microscopy revealed that the grain sizes increase from a value of 30–50 nm at ambient temperature to 120–150 nm at 503 K and remain approximately constant in this range up to 593 K. The existence of grain boundary walls of width 30–50 nm is demonstrated using phase contrast images. The grain boundary area also stagnates at higher substrate temperature. There is pronounced shape anisotropy as evidenced by the increased aspect ratio of the grains as a function of substrate temperature. Nickel thin films of 50 nm show the absence of long-range crystalline order at ambient temperature growth conditions and a preferred [111] orientation at higher substrate temperatures. Thin films are found to be thermally relaxed at elevated deposition temperature and having large compressive strain at ambient temperature. This transition from nanocrystalline to crystalline order causes a peak in the coercive field in the region of transition as a function of thickness and substrate temperature. The saturation magnetization on the other hand increases with increase in substrate temperature.University Grants Commission for Centre of Advanced Studies in Physic

Greening Capitalism? A Marxist Critique of Carbon Markets

Climate change is increasingly being recognized as a serious threat to dominant modes of social organization, inspiring suggestions that capitalism itself needs to be transformed if we are to ‘decarbonize’ the global economy. Since the Kyoto Protocol in 1997, carbon markets have emerged as the main politico-economic tools in global efforts to address climate change. Newell and Paterson (2010) have recently claimed that the embrace of carbon markets by financial and political elites constitutes a possible first step towards the transformation of current modes of capitalist organization into a new form of greener, more sustainable ‘climate capitalism.’ In this paper, we argue that the institutionalization of carbon markets does not, in fact, represent a move towards the radical transformation of capitalism, but is better understood as the most recent expression of ongoing trends of ecological commodification and expropriation, driving familiar processes of uneven and crisis-prone development. In this paper, we review four critical Marxist concepts: metabolic rift (Foster, 1999), capitalism as world ecology (Moore, 2011a), uneven development and accumulation through dispossession (Harvey, 2003, 2006), and sub-imperialism (Marini, 1972, 1977), developing a framework for a Marxist analysis of carbon markets. Our analysis shows that carbon markets form part of a longer historical development of global capitalism and its relation to nature. Carbon markets, we argue, serve as creative new modes of accumulation, but are unlikely to transform capitalist dynamics in ways that might foster a more sustainable global economy. Our analysis also elucidates, in particular, the role that carbon markets play in exacerbating uneven development within the Global South, as elites in emerging economies leverage carbon market financing to pursue new strategies of sub-imperial expansion. </jats:p