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A preliminary ichthyoplankton survey of the Tsitsikamma National Park
R.L. Tilney
African Zoology , 2012,
Abstract: ENGLISH ABSTRACT: An ichthyoplankton survey using bongo nets was conducted within the Tsitsikamma National Park over an 18-month period between January 1991 and July 1992. Four sampling stations along the coast were chosen, approximately 5 km apart. At each station four samples were taken along a transect perpendicular to the coast, between 0,35 km and 3,8 km offshore. Horizontal tows were taken at three and 15 m below the surface over reef and sand substrata respectively. Larvae belonging to 24 of the 35 families and 55 of the 97 species known to occur in the area were captured. Engraulid larvae completely dominated the catches while amongst the reef-associated taxa sparids and blenniids were prominent. Seasonally occurring cold upwelling event impacted negatively on egg and larval abundance. Mean values for egg and larval abundances were 1207 and 282 per 100m3 respectively. A relationship between larval number and plankton volume was revealed. Most larvae captured were between 2,0 and 20,3 mm (SL), and in the preflexion condition. The absence of larger size classes in samples was attributed to net avoidance. AFRIKAANSE OPSOMMING: 'n lgtioplankton-opname is oor 'n tydperk van 18 maande, tussen Januarie 1991 en Julie 1992 binne die Tsitsikamma Nasionale Park (TNP) gedoen met die gebruik van bongo-nette. Vier stasies is langs die kus gekies, ongeveer 5km uitmekaar. By elke stasie is vier monsters op ‘n lyn loodreg met die kus tussen 0,35 km en 3,8 km vanaf die strand geneem. Die nette is horisontaal getreil drie en 15 m onder die oppervlak en monsters is onderskeidelik oor sand een rif geneem. Larwes van 24 uit die 35 families en van 55 uit die 97 spesies wat in die TNP voorkom is gevang. Die familie Engraulidae het die vangste oorheers terwyl die Sparidae en Blenniidae prominent was onder die rifverwante visse. Seisoenale koue opwellings het 'n negatiewe uitwerking gehad op die hoeveelheid eiers en larwes. Gemiddelde waardes vir onderskeidelik eier- en larfhoeveelhede was 1207 en 282 per 100 m3. 'n Verwantskap tussen die larfhoeveelhede en planktonvolume is opgemerk. Die meeste van die larwes in die monsters was tussen 2,0 en 20,3 mm lank (SL) en in die voorverbuigingsvorm. Die afwesigheid van die groter klasgroottes is aan netontduiking toegeskryf.
TECHNIQUES TO MONITOR DRYING STRESSES AND DIMENSIONAL CHANGES IN TIMBER FROM PLANTATION-GROWN EUCALYPTS FOR KILN SCHEDULE DEVELOPMENT AND KILN CONTROL
Northway,R.L.;
Maderas. Ciencia y tecnología , 2002, DOI: 10.4067/S0718-221X2002000200005
Abstract: drying tests were conducted with timber from 13 year-old plantation-grown eucalyptus nitens and e. globulus, to determine shrinkage and drying degrade of tangential- and radial-sawn boards. the eucalypt species investigated exhibited a high level of collapse which was difficult to distinguish from normal shrinkage and confounded the results. nevertheless some useful conclusions about the potential for these techniques to indicate drying stress in plantation grown eucalyptus were drawn from the qualitative work undertaken: cup measurements on a half-thickness board, sealed on one face, provided a qualitative indication of stress reversal. this was confirmed with stress prongs. width of an artificial check did not provide a useful indication of the development of stress. transverse surface shrinkage measured across specimens and across a fixed core did not provide a useful indication of the development of stress. cup measurements and stress prongs indicated transverse strains at the surface while surface moisture content was still above fibre-saturation. non-contact measurement of shape change during drying showed some potential for indicating drying stress but needs higher resolution scanning and special image analysis techniques to be developed. optical profiling and image analysis may be useful in the development of a kiln control system based on material behaviour
The use of sunflower transcription factors as biotechnological tools to improve yield and stress tolerance in crops
Chan,R.L;
Phyton (Buenos Aires) , 2009,
Abstract: transcription factors (tfs) are proteins able to specifically recognize dna sequences in the regulatory regions of their target genes. they bind these specific sequences, an event that leads to the activation or repression of whole signal transduction pathways. in plants about 1500 tfs were informatically identified; identification was mainly based in the presence of dna-binding domains in the translated sequences. they were classified in families and subfamilies according to several features, including the conservation of the dna binding domain, the genes structures and the functions they exert. among transcription factors, several seem to be potential powerful biotechnological tools to improve crops via obtaining transgenic plants. assigned purposes include: yield improvements, abiotic and biotic stress tolerances, and a combination of them. none of them is up to date a product market, since from the gene discovery to the regulation process (which differs in each country) there is a long pipeline to run. since a few years ago, our research group is devoted to the structural and functional characterization of sunflower transcription factors, especially those belonging to the hd-zip family. members of this family exhibit in their structure a homeodomain (hd) associated to a leucine zipper (lz). this association is unique to plants, being these two domains common to transcription factors from several kingdoms. it was proposed by other authors, and also by us, that this unique association is probably due to specific plant responses as plant development, which depends on environmental conditions. in this work we show an overview and new insights of the sunflower hd-zip proteins, demonstrating to be useful biotechnological tools to confer drought, salt, herbicide, and herbivory (e.g. insect) tolerance, and other abiotic and biotic tolerance to stressgenerating factors. like other tfs, sunflower hd-zip transcription factors confer a complex phenotype to transgenic plants
Oscila??es de relaxa??o e suas aplica??es -I
Viana, R.L.;
Revista Brasileira de Ensino de Física , 2011, DOI: 10.1590/S1806-11172011000300004
Abstract: relaxation oscillations are maintained by a constant external influence and present two diferent timescales (fast and slow). they have properties diferent from the pendular oscillations which, for small amplitudes, reduce to harmonic oscillations. in this first paper we present the diferences between relaxation and pendular oscillations, showing illustrative examples of application of relaxation oscillations in a mechanical system (tantal vase) and an electric circuit.
Oscila??es de relaxa??o e suas aplica??es -II
Viana, R.L.;
Revista Brasileira de Ensino de Física , 2011, DOI: 10.1590/S1806-11172011000300005
Abstract: relaxation oscillations are maintained by a constant external influence and present two diferent timescales (fast and slow). in a previous paper we emphasized the qualitative diferences between pendular and relaxation oscillations, showing some physical examples. in this paper we present the pioneering contribution given to this subject by the dutch physicist balthazar van der pol, as well as some properties of the equation bearing his name, and which is one of the prototypes of nonlinear dynamical systems. we show applications of the van der pol equation in physics and biology.
A STUDY OF MARRIAGE ATTITUDE AND ADJUSTMENT AMONG ARTS AND SCIENCE FACULTY STUDENTS
R.L. BHARSAKHALE
Golden Research Thoughts , 2013, DOI: 10.9780/22315063
Abstract: Present study was framed to investigation of A study of marriage attitude and adjustment among art and science faculty students by employing a sample of 140 subjects in which 70 subjects were Arts faculty were Arts faculty (35 Male and 35 Female) and 70 subjects were Science faculty (35 Male and 35 Female) with age ranging from 21 to 24 years located From Aurangabad District were selected. The Marriage Attitude Scale. This scale was developed and standardized by Pramod Kumar and An Adjustment Inventory ( for school and College pupils). This scale was developed and standardized by Dr. Penni Jain. A factorial design was used; since there were two independent variables i.e. Faculty and Gender. A 2x2 factorial design was used to analyzing the data. It was found that the Science faculty students have positive marriage attitude from the arts faculty students and Science faculty students have good adjustment than arts faculty students.
TECHNIQUES TO MONITOR DRYING STRESSES AND DIMENSIONAL CHANGES IN TIMBER FROM PLANTATION-GROWN EUCALYPTS FOR KILN SCHEDULE DEVELOPMENT AND KILN CONTROL
R.L. Northway
MADERAS : Ciencia y Tecnología , 2002,
Abstract: Drying tests were conducted with timber from 13 year-old plantation-grown Eucalyptus nitens and E. globulus, to determine shrinkage and drying degrade of tangential- and radial-sawn boards. The eucalypt species investigated exhibited a high level of collapse which was difficult to distinguish from normal shrinkage and confounded the results. Nevertheless some useful conclusions about the potential for these techniques to indicate drying stress in plantation grown Eucalyptus were drawn from the qualitative work undertaken: Cup measurements on a half-thickness board, sealed on one face, provided a qualitative indication of stress reversal. This was confirmed with stress prongs. Width of an artificial check did not provide a useful indication of the development of stress. Transverse surface shrinkage measured across specimens and across a fixed core did not provide a useful indication of the development of stress. Cup measurements and stress prongs indicated transverse strains at the surface while surface moisture content was still above fibre-saturation. Non-contact measurement of shape change during drying showed some potential for indicating drying stress but needs higher resolution scanning and special image analysis techniques to be developed. Optical profiling and image analysis may be useful in the development of a kiln control system based on material behaviour
An Examination of Free Cash Flow Hypothesis in Indian Repurchase Decisions
Hyderabad, R.L.
Asian Journal of Business Management , 2013,
Abstract: Repurchase of shares by Indian firms are on the rise in recent years. What motivates Indian firms to repurchase their own shares? Signalling and free cash flow hypotheses are two competitive and popular explanations identified in empirical research in US and other countries. Do Indian firms buy back their shares to correct market misvaluations or to return excess funds? In the present paper an effort is made to decipher the motives behind repurchase decisions of Indian firms. Since there are positive returns only on announcement day and not in post-announcement days the signalling hypothesis cannot be an explanation for positive overall CAR in Indian announcements. The study hypothesizes that Indian firms use repurchases as a part of overall corporate restructuring mechanism of distributing excess funds and build promoters' stake holding. The evidence shows that low-q firms with higher free cash flow ratio earn higher abnormal returns than other firms. The cross-sectional analysis generates positive coefficient for low-q firms with higher cash flow and promoters' control.
THE CIVIL WAR: BIRTHPLACE OF THE NEW NAVY
R.L. Shelver
Scientia Militaria : South African Journal of Military Studies , 2012, DOI: 10.5787/8-1-798
Abstract: When the campaigns of the American Civil War are recalled the names that come to mind are Petersburg, Gettysburg, Manassas, Fredericksburg and Bull Run. All of these were land battles, yet the soldiers' war contributed very little to the tactics or weaponry of modern warfare. On the other hand the unpublicised naval engagements of the era were punctuated with innovations that have remained part of today's Navy.
The multicolored Asian lady beetle, Harmonia axyridis: A review of its biology, uses in biological control, and non-target impacts
R.L. Koch
Journal of Insect Science , 2003,
Abstract: Throughout the last century, the multicolored Asian lady beetle, Harmonia axyridis (Pallas) has been studied quite extensively, with topics ranging from genetics and evolution to population dynamics and applied biological control being covered. Much of the early work on H. axyridis was conducted in the native Asian range. From the 1980's to the present, numerous European and North American studies have added to the body of literature on H. axyridis. H. axyridis has recently gained attention in North America both as a biological control agent and as a pest. This literature review was compiled for two reasons. First, to assist other researchers as a reference, summarizing most of the voluminous body of literature on H. axyridis pertaining to its biology, life history, uses in biological control, and potential non-target impacts. Secondly, to be a case study on the impacts of an exotic generalist predator.
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