8 research outputs found
Simulation of fluidized-bed drying of carrot with microwave heating
A mathematical model of coupled heat and mass transfer was applied to batch fluidized-bed drying with microwave heating of a heat sensitive material-carrot. Four kinds of microwave heating with intermittent variation were examined. The numerical results show that different microwave heating patterns can affect the fluidized bed drying significantly. Changing the microwave input pattern from uniform to intermittent mode can prevent material from overheating under the same power density. Supplying more microwave energy at the beginning of drying can increase the utilization of microwave energy while keeping temperature low within the particle. For a particle diameter of 4mm, fluidization velocity of 2 m/s, inlet airflow temperature of 70degreesC and the bed area factor of 80, the drying time are 750 and 1000s, respectively, for the two good operating conditions with on/off periods of 125/375s and 375/375s. The cumulative microwave energy absorbed by particles at the end of drying is 1415 and 2300kJ/kg (dry basis), respectively
Selective HPLC method development for soy phosphatidylcholine fatty acids and its mass spectrometry
A novel, efficient and simple approach for soy phosphatidylcholine analysis according to its fatty acid composition was studied with reverse-phase high-performance liquid chromatography. The reverse-phase high-performance liquid chromatography analysis was performed isocratically using UV detector and simple mobile phase solvents consisting of isopropyl alcohol, methanol, and deionized water in the proportion of 70:8:22 v/v. The uniqueness of the proposed method was the separation of individual fatty acids of soy phosphatidylcholine. The high-performance liquid chromatography method for soy phosphatidylcholine was validated for linearity with correlation coefficient of above 0.99 for all the peaks separated according to their fatty acid composition. The intra-day and the inter-day precision studies provided the relative standard deviation of less than 2%. The limit of detection and limit of quantitation values were also calculated for all the resolved peaks of soy phosphatidylcholine. Also system performance parameters such as number of theoretical plates, capacity factor, tailing factor, separation factor, and peak resolution were studied systematically and found well within the acceptable range. The proposed high-performance liquid chromatography method was successfully applied to soy phosphatidylcholine extracted and purified from deoiled soy lecithin without any interference of impurities or solvent peaks. Individually, the collected peaks of sample soy phosphatidylcholine were subjected for mass spectroscopy. The mass spectra showed all the peaks having different saturated or unsaturated fatty acid chains attached to glyerophosphocholine moiety of soy phosphatidylcholine. The method developed is economic and well suited for estimation of soy phosphatidylcholine with its fatty acid composition
Reversed-phase High-performance Liquid Chromatography Method for Analysis of Curcuminoids and Curcuminoid-loaded Liposome Formulation
A simple, sensitive, precise and specific method for the determination of curcuminoids and curcuminoid-loaded liposome formulation was developed using reverse-phase high-performance liquid chromatography method. The analysis was performed isocratically on Zorbax Eclipse XDB-C18 column (150Ă—4 mm, 5 ÎĽm), analytical column using UV detector and mobile phase consisting of 0.1% orthophosphoric acid and acetonitrile. The proposed method for curcuminoids was validated for linearity in the range from 50 to 300 Î…g/ml with correlation coefficient above 0.997. Intraday and interday precision studies showed the relative standard deviation less than 2%. The limit of detection and limit of quantitation values were 2.5 and 8.25 Î…g/ml, respectively. Forced degradation study for curcuminoids and liposomal curcuminoids sample was carried out and observed that proposed method was also suitable for finding degradation products in the sample. Proposed method was successfully applied to estimate curcuminoids content without any interference of other excipients from liposomal formulation. Therefore, the method developed is well suited for curcuminoids and its liposome estimation
“If It’s Not Working, Why Would They Be Testing It?”: mental models of HIV vaccine trials and preventive misconception among men who have sex with men in India
BACKGROUND: Informed consent based on comprehension of potential risks and benefits is fundamental to the ethical conduct of clinical research. We explored mental models of candidate HIV vaccines and clinical trials that may impact on the feasibility and ethics of biomedical HIV prevention trials among men who have sex with men (MSM) in India. METHODS: A community-based research project was designed and implemented in partnership with community-based organizations serving MSM in Chennai and Mumbai. We conducted 12 focus groups (n = 68) with diverse MSM and 14 key informant interviews with MSM community leaders/service providers using a semi-structured interview guide to explore knowledge and beliefs about HIV vaccines and clinical trials. Focus groups (60–90 minutes) and interviews (45–60 minutes) were conducted in participants’ native language (Tamil in Chennai; Marathi or Hindi in Mumbai), audio-taped, transcribed and translated into English. We explored focus group and interview data using thematic analysis and a constant comparative method, with a focus on mental models of HIV vaccines and clinical trials. RESULTS: A mental model of HIV vaccine-induced seropositivity as “having HIV” resulted in fears of vaccine-induced infection and HIV stigma. Some participants feared inactivated vaccines might “drink blood” and “come alive”. Pervasive preventive misconception was based on a mental model of prevention trials as interventions, overestimation of likely efficacy of candidate vaccines and likelihood of being assigned to the experimental group, with expectations of protective benefits and decreased condom use. Widespread misunderstanding and lack of acceptance of placebo and random assignment supported perceptions of clinical trials as “cheating”. Key informants expressed concerns that volunteers from vulnerable Indian communities were being used as “experimental rats” to benefit high-income countries. CONCLUSIONS: Evidence-informed interventions that engage with shared mental models among potential trial volunteers, along with policies and funding mechanisms that ensure local access to products that demonstrate efficacy in trials, may support the safe and ethical implementation of HIV vaccine trials in India
Preclinical and clinical trials of Indian medicinal plants in disease control
Since the ancient period, the medicinal plants have been used in pharmaceutical and cosmetic industries. Recently, it has gained extreme research importance for their nutraceuticals values. It has been confirmed by WHO that herbal medicines serve the health needs of about 80% of World’s population; especially for millions of people in the vast rural areas of developing countries. This book chapter summarizes the importance of several medicinal plants which are traditionally used in treatment and management of different ailments in India. In addition, some pharmacological models describe the possible mechanism of action of bioactive phytochemicals, which can be successfully used as drug candidates in near future. However, there is urgent need for basic scientific investigations on medicinal plants and this has been highlighted in current research trends in clinical trials