Preparation of pure boehmite, alpha-Al2O3 and their mixtures by hydrothermal oxidation of aluminium metal

A hydrothermal oxidation process for preparing pure boehmite, alpha-Al2O3, and their mixtures by oxidation of pure aluminum metal is described, and the reaction mechanisms involved are identified. SEM images are presented which show distinct morphologies of boehmite, alpha-Al2O3, and boehmite + alpha-Al2O3 phases. Near sperical shapes of alpha-Al2O3 powder phases are obtained at 550 C with 30 percent volume of fill

Development and validation of dissolution test for Metoprolol sustained release capsules

Dissolution test for sustained release capsules of Metoprolol 125 mg was developed and validated according to FDA and ICH guidelines. Metoprolol coated pellets were coated with microcrystalline wax and glyceryl distearate for slow release of drug. The dissolution method which uses USP apparatus I (Basket) with rotating at 100 rpm, 900 ml of different dissolution medium, ultra violet spectroscopy for quantification was demonstrated to be robust, discriminating and transferable. Dissolution tests conditions were selected after it was demonstrated that the Metoprolol rapidly dissolved in the aqueous media over the pH range of 1.2 to 7.

An investigation of the impact of promotions on across-submarket competition

There is a recent trend among manufacturers of consumer packaged goods such as Proctor & Gamble to eliminate sales promotions and replace them with everyday low prices on their products. The objective of this study is to investigate whether and how such a significant change in promotional strategy would affect the competitive patterns in a market. Specifically, what would be the impact of such a move on competition between different brands in a market? Would the competitive structure change significantly as a result? How would this affect specific brands? We propose a methodology based on a dogit model of brand switching to evaluate and test the impact of promotions on competitive structure and to identify the nature of the impact. Our findings reveal that some sales promotions (e.g., displays and price cuts) have a significant impact in shaping competitive patterns characterizing submarkets for crackers. The magnitude of this impact decreases with increased product differentiation and increased intensity of the promotional activities in the market. Our findings help managers determine how the elimination of certain sales promotions may reshape competitive patterns before making such a move. The knowledge of which submarket boundaries are stable and which boundaries can be affected by promotions also helps managers decide which product alternatives to promote (or not to promote) so as to maximize short-term revenues. © 2001 Elsevier Science Inc.postprin

Prevalence and clinical presentation of Post-COVID syndrome in patients recovered from acute COVID infections in North Kerala

Background: Post-acute COVID symptoms have become a major health concern and one of the most important causes of morbidity throughout the world. Hence, it is important to document the pattern of presentation in post-COVID syndrome patients in India, which has been one of the countries with the largest acute COVID-19 infections. Aims and Objectives: This study was done to estimate the prevalence of post-acute COVID syndrome in patients recovered from acute COVID infection and to determine the factors influencing with its incidence. Materials and Methods: Community-based observational study in which patients who have recovered from acute COVID infection 3–6 months before the study period were selected using multistage sampling. Data were collected through house visits using a pre-validated questionnaire containing details of acute COVID-19 infection, treatment taken, vaccination status before the infection, symptoms in the period between 4 and 12 weeks, and symptoms after 12 weeks of acute COVID infection. Results: Out of the 265 patients studied, 14.34% had ongoing symptomatic COVID-19 in the first 3 months of acute illness and 9.81% had post-COVID symptoms even after 3 months. 17.74% of the patients had a history of pre-existing comorbid illnesses and 31.32% had received two doses of vaccination before acquiring COVID-19 infection. 92.83% were treated in home quarantine, 4.91% needed hospitalization without oxygen supplementation, and 2.26% required oxygen or ventilatory support. The most common post-COVID symptoms reported were tiredness, easy fatiguability, breathlessness, and body ache. Female gender, presence of comorbidities, and mode of treatment had a significant role in predicting the incidence of post-COVID symptoms. Conclusion: The study clearly showed that the severity of acute COVID infection has a significant correlation with the incidence of both ongoing symptomatic COVID and post-COVID syndrome. Other factors that increased the incidence included female gender and pre-existing comorbidities

Consumer Connectivity in a Complex, Technology-Enabled, and Mobile-Oriented World with Smart Products

Today’s consumers are immersed in a vast and complex array of networks. Each network features an interconnected mesh of people and firms, and now, with the rise of the Internet of Things (IoT), also objects. Technology (particularly mobile devices) enables such connections, and facilitates many kinds of interactions in these networks - from transactions, to social information sharing, to people interfacing with connected devices (e.g., wearable technology). We introduce the POP-framework, discuss how People, Objects and the Physical world interconnect with each other and how it results in an increasing amount of connected data, and briefly summarize existing knowledge on these inter-connections. We also provide an agenda for future research focused on examining potential impact of IoT and smart products on consumer behavior and firm strategies

A serine-substituted P450 catalyzes highly efficient carbene transfer to olefins in vivo

Whole-cell catalysts for non-natural chemical reactions will open new routes to sustainable production of chemicals. We designed a cytochrome 'P411' with unique serine-heme ligation that catalyzes efficient and selective olefin cyclopropanation in intact Escherichia coli cells. The mutation C400S in cytochrome P450_(BM3) gives a signature ferrous CO Soret peak at 411 nm, abolishes monooxygenation activity, raises the resting-state FeIII-to-FeII reduction potential and substantially improves NAD(P)H-driven activity

Free exopolysaccharide from Mycoplasma mycoides subsp. mycoides possesses anti-inflammatory properties

In this study we explored the immunomodulatory properties of highly purified free galactan, the soluble exopolysaccharide secreted by Mycoplasma mycoides subsp. mycoides (Mmm). Galactan was shown to bind to TLR2 but not TLR4 using HEK293 reporter cells and to induce the production of the anti-inflammatory cytokine IL-10 in bovine macrophages, whereas low IL-12p40 and no TNF-α, both pro-inflammatory cytokines, were induced in these cells. In addition, pre-treatment of macrophages with galactan substantially reduced lipopolysaccharide (LPS)-induced production of pro-inflammatory cytokines TNF- and IL-12p40 while increasing LPS-induced secretion of immunosuppressive IL-10. Also, galactan did not activate naïve lymphocytes and induced only low production of the Th1 cytokine IFN-γ in Mmm-experienced lymphocytes. Finally, galactan triggered weak recall proliferation of CD4+ T lymphocytes from contagious bovine pleuropneumonia-infected animals despite having a positive effect on the expression of co-stimulatory molecules on macrophages. All together, these results suggest that galactan possesses anti-inflammatory properties and potentially provides Mmm with a mechanism to evade host innate and adaptive cell-mediated immune responses. (Résumé d'auteur

Pyrethroid resistance in Anopheles gambiae leads to increased susceptibility to the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana

<p>Abstract</p> <p>Background</p> <p>Entomopathogenic fungi are being investigated as a new mosquito control tool because insecticide resistance is preventing successful mosquito control in many countries, and new methods are required that can target insecticide-resistant malaria vectors. Although laboratory studies have previously examined the effects of entomopathogenic fungi against adult mosquitoes, most application methods used cannot be readily deployed in the field. Because the fungi are biological organisms it is important to test potential field application methods that will not adversely affect them. The two objectives of this study were to investigate any differences in fungal susceptibility between an insecticide-resistant and insecticide-susceptible strain of <it>Anopheles gambiae sensu stricto</it>, and to test a potential field application method with respect to the viability and virulence of two fungal species</p> <p>Methods</p> <p>Pieces of white polyester netting were dipped in <it>Metarhizium anisopliae </it>ICIPE-30 or <it>Beauveria bassiana </it>IMI391510 mineral oil suspensions. These were kept at 27 ± 1°C, 80 ± 10% RH and the viability of the fungal conidia was recorded at different time points. Tube bioassays were used to infect insecticide-resistant (VKPER) and insecticide-susceptible (SKK) strains of <it>An. gambiae s.s</it>., and survival analysis was used to determine effects of mosquito strain, fungus species or time since fungal treatment of the net.</p> <p>Results</p> <p>The resistant VKPER strain was significantly more susceptible to fungal infection than the insecticide-susceptible SKK strain. Furthermore, <it>B. bassiana </it>was significantly more virulent than <it>M. anisopliae </it>for both mosquito strains, although this may be linked to the different viabilities of these fungal species. The viability of both fungal species decreased significantly one day after application onto polyester netting when compared to the viability of conidia remaining in suspension.</p> <p>Conclusions</p> <p>The insecticide-resistant mosquito strain was susceptible to both species of fungus indicating that entomopathogenic fungi can be used in resistance management and integrated vector management programmes to target insecticide-resistant mosquitoes. Although fungal viability significantly decreased when applied to the netting, the effectiveness of the fungal treatment at killing mosquitoes did not significantly deteriorate. Field trials over a longer trial period need to be carried out to verify whether polyester netting is a good candidate for operational use, and to see if wild insecticide-resistant mosquitoes are as susceptible to fungal infection as the VKPER strain.</p