106 research outputs found
Operating characteristics of an electrically assisted turbofan engine
No full textWith the growing pressure to reduce the environmental footprint of aviation, new and efficient propulsion systems must be investigated. The current research looks at the operating characteristics of a turbofan engine in a parallel hybrid-electric propulsion system. Electric motors are used to supply power in the most demanding take-off and climb phases to achieve the required thrust, which allows the turbofan to be redesigned to maximize the cruise performance (to some extent). It was found that the turbofan's cruise efficiency can be improved by 1.0% by relaxing the constraints of take-off and climb. It was found that the surge margins of compressors limit the amount of power that could be electrically supplied. On a short-range mission, the hybrid-electric propulsion system showed a potential to reduce around 7% of fuel burn on an A320 class aircraft. Most of these savings are however achieved due to fully electric taxiing. The weight of the electrical propulsion system largely offsets the efficiency improvements of the gas turbine during cruise flight. A system dedicated for fully electric taxiing system could provide similar savings, at less effort and costs. Given the optimistic technology levels used in the current analysis, parallel hybrid-electric propulsion is not likely to be used in the next-generation short to medium range aircraft.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Aircraft Noise and Climate EffectsFlight Performance and Propulsio
Scientometric portrait of Ram Gopal Rastogi
Get PDFPublication productivity of Indian scientist (R.G. Rastogi) has been documented.
Scientometric analysis of 312 papers by Ram Gopal Rastogi published during 1954 to 1992 in various domains: (a) Luni -solar activity and quiet -time E & F- region (57); (b) Equatorial electric field and low and mid latitude iof:osphere (78); (c) Ionospheric E- region irregularities (19); (dj Ionospheric F- region irregularities (32); and (e) Magnetic disturbance effects on the equatorial low and mid latitude ionosphere (23) were analysed. Interdomainery contents and of the number of papers: a+b were 36; b+c and b+d were 20 each; b+e were 16;. c+e were 5; a+e were 3; d+e were 2; and a+d had only one publication. Highest collaborations were with H. Chandra (61), M.R. Deshpande (42), and G. Sethia (19) out of his total 97 collaborators. His highest productivity was during 1978 with 28 papers followed by 19 papers during 1977. The core journals preferred by him for publishing papers were: Indian Journal of Radio & Space Physics, India, and Journal of Atomic & Terrestrial Physics, UK (59 each), followed by Proceedings of the Indian Academy of Sciences, India (34). Most prolific title keywords with their frequencies were: Ionosphere (92); Equatorial (61); F-region (53); Equatorial electrojet region (40), and Magnetic equator (30)
Amazonian plants from ethnomedicine to biotechnology through pharmaceutical biology approaches: a PhD experience in connecting forest with laboratory
No full textThe South american Natives, Shuar and Achuar people and their ethnomedical culture constitute the
background subject of the Phd research, performed both in Ecuador (Salesian Politechnic University,
Quito), and in Italy (Pharmaceutical biology labs, University of Ferrara). Based on ethnomedical
responses, Piper aduncum, Maytenus macrocarpa, Schinus molle, Tecoma stans and Eugenia hallii were
chosen as amazonian plant species subject of the research.
AIMS
The research has been focused on:
− checking the presence of endophytic fungi in plants;
− isolating and subculturing pure endophytic strains;
− checking the biotransformation capacity of the isolated endophytes on pure compounds; the most
performing endophytes were also tested on phytocomplexes and pure chemicals obtained by the
plant from which the fungi were isolated;
− phytochemical characterization and bioactivity assays of plant extracts: P. aduncum.
−
METHODS
Biotransformations. Fresh aerial plant parts were properly washed in sanitizing solutions and in vitro
cultured using adequate solid media to isolate endophytes. (+/-)-cis-bicyclo[3.2.0]hept-2-en-6-one,
acetophenone, 1-indanone, 2-furyl methyl ketone, 2-methylcyclopentanone, 2-methylcyclohexanone, 2-
methoxycyclohexanone were chosen as substrate model for biotransformations. The cultures were
sampled after 1, 3, 7, 10 days of culturing, and ethyl acetate extracted to verify by GC-MS the presence of
possible biotransformation products. Biotransformations were also checked on P. aduncum whole
essential oil and on dillapiol, cis-ocimene, piperitone, (-)-terpinen-4-ol as most abundant chemicals.
Chemical fingerprinting of P. aduncum essential oil. Steam distillation was adopted to obtain the essential
oil, then characterized by GC-MS, NMR analyses.
In vitro bioassays of P. aduncum essential oil. Antimicrobial activities were checked in vitro using proper
agarized media to reach MIC. Antioxidant capacities were checked through DPPH test, ABTS and
photochemiluminescence assays. Born's turbidimetric method and Writhing test were respectively
adopted to check platelet-aggregation and anti-nociceptive properties. Mutagenic, antimutagenic
properties and toxicity were assayed using classical and modified Ames test.
MAIN RESULTS
364 fungal strains were in vitro isolated. Among all, 5 strains performed biotransformations on
acetophenone to (S)-1-phenylethanol, with important yields (78-97%) and enantiomeric excess (78-
100%). Three strains gave also phenols probably by enzymatic reactions (Baeyer-Villiger oxidations). 15
fungal strains gave the lactones (-)-(1S,5R)-2-oxabicyclo[3.3.0]oct-6-en-3-one and (-)-(1R,5S)-3-
oxabicyclo[3.3.0]oct-6-en-2-one from (+/-)-cis-bicyclo[3.2.0]hept-2-en-6-one, probably as result of
monooxygenase activation. Phytochemical characterization of P. aduncum essential oil has evidenced
dillapiol as the most abundant terpene, followed by cis-ocimene, piperitone and terpinen-4-ol. Only cisocimene
and piperitone gave several biotransformation products through dehydrogenation and
hydroxylation reactions. The essential oil has evidenced non-mutagenic properties and interesting
antifungal and antioxidant activities.
CONCLUSIONS
Several endophytic fungal strains from Amazonian plants were isolated and checked for
biotransformations on pure chemicals and on P. aduncum essential oil. Data obtained will be useful for
possible following patents about micro-organisms able to transform pharmaceutically interesting
chemicals. Taxonomical characterization of the most performing fungal strains is still in progress. P.
aduncum essential oil can be considered genotoxically safe and provides interesting antifungal and
antioxidant properties, supporting its ethnomedical use as cicatrising and disinfectant crude drug and
suggesting an extension of its employ as preservative ingredient
Proteomic Analysis in Diabetic Cardiomyopathy using Bioinformatics Approach
No full text Diabetic cardiomyopathy is a distinct clinical entity that produces asymptomatic heart failure in diabetic patients without evidence of coronary artery disease and hypertension. Abnormalities in diabetic cardiomyopathy include: myocardial hypertrophy, impairment of contractile proteins, accumulation of extracellular matrix proteins, formation of advanced glycation end products, and decreased left ventricular compliance. These abnormalities lead to the most common clinical presentation of diabetic cardiomyopathy in the form of diastolic dysfunction. We evaluated the role of various proteins that are likely to be involved in diabetic cardiomyopathy by employing multiple sequence alignment using ClustalW tool and constructed a Phylogenetic tree using functional protein sequences extracted from NCBI. Phylogenetic tree was constructed using Neighbour—Joining Algorithm in bioinformatics approach. These results suggest a causal relationship between altered calcium homeostasis and diabetic cardiomyopathy that implies that efforts directed to normalize calcium homeostasis could form a novel therapeutic approach. </jats:p
Proteomic Analysis in Diabetic Cardiomyopathy using Bioinformatics Approach
No full textDiabetic cardiomyopathy is a distinct clinical entity that produces asymptomatic heart failure in diabetic patients without evidence of coronary artery disease and hypertension. Abnormalities in diabetic cardiomyopathy include: myocardial hypertrophy, impairment of contractile proteins, accumulation of extracellular matrix proteins, formation of advanced glycation end products, and decreased left ventricular compliance. These abnormalities lead to the most common clinical presentation of diabetic cardiomyopathy in the form of diastolic dysfunction. We evaluated the role of various proteins that are likely to be involved in diabetic cardiomyopathy by employing multiple sequence alignment using ClustalW tool and constructed a Phylogenetic tree using functional protein sequences extracted from NCBI. Phylogenetic tree was constructed using Neighbour—Joining Algorithm in bioinformatics approach. These results suggest a causal relationship between altered calcium homeostasis and diabetic cardiomyopathy that implies that efforts directed to normalize calcium homeostasis could form a novel therapeutic approach
Seven-year experience of using Repiphysis® expandable prosthesis in children with bone tumors
No full textBackground. Results of the use of the non-invasive expandable endoprosthetic device Repiphysis® in limb salvage surgery for skeletally immature children with bone cancer have been promising. Procedure. In this report, we analyze the outcomes and complications associated with using 17 Repiphysis® prosthesis from January 2002 to March 2009 in 17 skeletally immature children with bone sarcoma around the knee. Results. The average follow-up was 61.7 months. All patients who underwent active expansion experienced successful lengthening with a total of 38 lengthening sessions and an average of 8.6 mm gained per session. The Musculoskeletal Tumor Society functional scores averaged 90percent at the most recent follow-up. The average survival time of the device from implementation to revision or last follow-up was 2 years and 8 months. There were 12 complications in 12 patients, including 6 mechanical problems, 2 tibial fractures and 3 infections. For the 17 insertions, 7 revision operations were performed, 3 of which were done using a new Repiphysis® device. Conclusions. Despite the high rate of complications, the goal of achieving equal leg length at skeletal maturity with fewer surgeries per patient has been relatively achieved with the use of this device. © 2010 Wiley-Liss, Inc.Abed YY, 2009, J BONE JOINT SURG BR, V91B, P1366, DOI [10.1302-0301-620X.91B10.22212, 10.1302-0301-620V.91B10.22212]; Baumgart Rainer, 2009, V179, P59; Baumgart R, 1997, CLIN ORTHOP RELAT R, P135; CAMMISA FP, 1990, J BONE JOINT SURG AM, V72A, P1541; Eckardt JJ, 2000, CLIN ORTHOP RELAT R, P51; ECKARDT JJ, 1993, CLIN ORTHOP RELAT R, P188; Gitelis S, 2003, Chir Organi Mov, V88, P327; Gupta A, 2006, J BONE JOINT SURG BR, V88B, P649, DOI 10.1302-0301-620X.88B5.17098; Haidar R, 2008, PEDIATR BLOOD CANCER, V51, P787, DOI 10.1002-pbc.21696; Hosalkar HS, 2004, PEDIATR BLOOD CANCER, V42, P295, DOI 10.1002-pbc.10406; KENAN S, 1991, CLIN ORTHOP RELAT R, P223; LEWIS MM, 1986, CANCER, V57, P499, DOI 10.1002-1097-0142(19860201)57:3499::AID-CNCR28205703163.0.CO;2-Z; Neel MD, 2003, CLIN ORTHOP RELAT R, P72, DOI 10.1097-01.blo.0000093899.12372.25; ROUGRAFF BT, 1994, J BONE JOINT SURG AM, V76A, P649; Schindler OS, 1997, J BONE JOINT SURG BR, V79B, P927, DOI 10.1302-0301-620X.79B6.7164; VANNES CP, 1950, J BONE JOINT SURG BR, V32, P12; Ward WG, 1996, ORTHOP CLIN N AM, V27, P493; Wilkins RM, 2001, CLIN ORTHOP RELAT R, P5110121
Sex trafficking of girls and women : Evidence from Anantapur district, Andhra Pradesh
Get PDFA crucial gap in the trafficking literature from India is the dearth of primary data and micro studies that could be used for vulnerability mapping of the source areas and addressing the identified risk factors. The present paper is a small attempt to contribute to plugging the gap in the context of Andhra Pradesh, identified as a hot spot in the trafficking literature. This paper is based on case studies of 78 women who had been trafficked from their places of origin in Anantapur district in Andhra Pradesh to metropolitan cities across India and who have since returned to their homes. The paper attempted to identify the individual and family circumstances that contribute to the causes of trafficking, to highlight in particular the gendered vulnerabilities that set these women up for trafficking, and to capture the process of the trafficking experience. The findings of the study are located in the dynamic interplay of the social structural context and specificities of the district that contribute to causes of trafficking and the individual circumstances and agency of the women. The case studies reported in this paper are a pointer to the compelling urgency of interventions that will go beyond the forced / voluntary divide in trafficking and sex work.Andhra Pradesh, India, trafficking
Facilitating Image and Document Retrieval Using Image Content and Querying Keyword
Get PDFEvolution of ubiquitous computing in the areas of personal computing technology has produced staggeringly large data It is difficult to search mainly the image data by understanding users objective only by keywords and phrases and this leads to uncertain outcomes. For producing these outcomes effectively, this paper introduces a new approach to the problem of image learning to enable search engines to learn about visual content over time based on user feedback through one click activity and images from a pool recovered by text based query are re-ranked depending on both visual and text based query. Content Based Image Retrieval (CBIR) techniques are used for accessing semantically-relevant images from an image data source depending on automatically-derived image functions for features like Geometric moments, Global histogram, Color Moments, Local histogram. Documents can also be retrieved using the text based query by the user
Population Aging in Canada: Software for Exploring the Implications for the Labour Force and the Productive Capacity of the Economy
Get PDFThis report has two purposes: (1) to introduce a new version of the MEDS (Models of the Economic Demographic System) software; and (2) to apply it in a series of illustrative projections. The software is designed to illustrate the medium- to longer-term responses of the Canadian population and economy to a wide range of factors on either the demographic side, such as changes in rates of fertility, migration, and mortality, or the economic side, such as changes in the rate of technical progress or the educational attainment of young people or of new immigrants. "Standard" projections are provided, together with nineteen alternative projections. (For some illustrative projections, see http://socserv.mcmaster.ca/qsep.) The range of projections indicates the breadth of applications for which MEDS has been designed. It serves also to provide some quantitative measures of the likely demographic and economic consequences of population aging, and indicates the scope for evaluating policy initiatives by means of simulation.macroeconomic projections, economic-demographic system
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