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Seston fluxes in the dam of a Colombian tropical reservoir
Moreno, Yimmy Montoya;Ramirez, John Jairo;
Acta Limnologica Brasiliensia , 2010, DOI: 10.4322/actalb.02203009
Abstract: aim: quantify sedimentation rates in rio grande ii reservoir, his temporal fluctuation, and the degree of mineralization of the material that reaches the sediment; methods: a system of five sedimentation traps was used to evaluate temporal variability of seston flux and the total sedimentation in the dam of río grande ii reservoir antioquia-colombia (6° 32, 62' n, 75° 27, 27' w); results: the flux total solids presented a mean value of 4540 g.m-2.d-1 with a range oscillating between 229 and 18573 g.m-2.d-1, being the fixed and suspended fraction the most of the total solids. it was evidenced that the largest fluxes were presented between the fourth and the fifth trap (the nearest to the bottom) due to hypolimnetic fluxes which contain materials of the tributaries and resuspended material. the first three traps collected particles that settled from the column of water without evaluate the overtrapping for resuspension. in some samplings the mineralization between the third and fourth trap was maximum (100%). the fluxes of seston particles presented a mean value of 3554 g.m-2.d-1 with a range between 810 and 18955 g.m-2.d-1, being predominant the inorganic fraction; conclusions: the seston is mainly of allochthonous origin and variated in the time and in the vertical level. there was not found a significant relationship between level of the reservoir and the mixing depth with the fluxes of total sedimentation and seston; however there was relation between seston concentration and wind speed.
Cladocerans (Branchiopoda) of a tropical estuary in Brazil
Paranaguá, M. N;Neumann-Leit?o, S;Nogueira-Paranhos, J. D;Silva, T. A.;Matsumura-Tundisi, T.;
Brazilian Journal of Biology , 2005, DOI: 10.1590/S1519-69842005000100015
Abstract: the study was conducted in the capibaribe river estuary in recife (brazil) to assess the role played by cladocerans in a eutrophic environment. samplings were carried out monthly at 4 fixed stations along the estuary from july 1987 to june 1988. collections were made with a plankton net of 65 micrometers mesh size. six cladocerans species were registered: penilia avirostris, diaphanosoma spinulosum, chydorus barroisi, ceriodaphnia rigaudi, ilyocryptus spinifer, and moina micrura. the most frequent species was moina micrura with 49%. the only true marine species was penilia avirostris, which was registered at station 1 (close to the river mouth), during high and low tide and in the dry season. the cladocera average density decreased from 329 ind.m-3 (august 1987, high tide) to 2 ind.m-3 (march 1988, high tide) due to the high load of organic and chemical pollution received by the estuary. at all stations, d. spinulosum, m. micrura, and c. barroisi occurred with a wide distribution, mainly during the rainy season. c. rigaudi and i. spinifer were rare, occurring only during the rainy season. cladocerans played an important role in the food webs of the plankton community of the capibaribe tropical estuary and the dominance of a few small species indicated a hypereutrophic environment. a high level of disturbance was indicated by the decline in diversity of specialized species and the increase in abundance of opportunistic species like m. micrura.
Seston fluxes in the dam of a Colombian tropical reservoir Fluxos de seston na barragem de um reservatório tropical Colombiano
Yimmy Montoya Moreno,John Jairo Ramirez
Acta Limnologica Brasiliensia , 2010, DOI: doi: 10.4322/actalb.02203009
Abstract: AIM: Quantify sedimentation rates in Rio Grande II reservoir, his temporal fluctuation, and the degree of mineralization of the material that reaches the sediment; METHODS: A system of five sedimentation traps was used to evaluate temporal variability of seston flux and the total sedimentation in the dam of Río Grande II reservoir Antioquia-Colombia (6° 32, 62' N, 75° 27, 27' W); RESULTS: The flux total solids presented a mean value of 4540 g.m-2.d-1 with a range oscillating between 229 and 18573 g.m-2.d-1, being the fixed and suspended fraction the most of the total solids. It was evidenced that the largest fluxes were presented between the fourth and the fifth trap (the nearest to the bottom) due to hypolimnetic fluxes which contain materials of the tributaries and resuspended material. The first three traps collected particles that settled from the column of water without evaluate the overtrapping for resuspension. In some samplings the mineralization between the third and fourth trap was maximum (100%). The fluxes of seston particles presented a mean value of 3554 g.m-2.d-1 with a range between 810 and 18955 g.m-2.d-1, being predominant the inorganic fraction; CONCLUSIONS: The seston is mainly of allochthonous origin and variated in the time and in the vertical level. There was not found a significant relationship between level of the reservoir and the mixing depth with the fluxes of total sedimentation and seston; however there was relation between seston concentration and wind speed. OBJETIVO: Quantificar taxas de sedimenta o no reservatório do Rio Grande II, sua flutua o temporal, bem como o grau de mineraliza o do material que chega ao sedimento; MéTODOS: Foi utilizado um sistema de cinco armadilhas de sedimenta o para avaliar a variabilidade temporal do fluxo total de seston e a sedimenta o no reservatório Rio Grande II, Antioquia-Colombia (6° 32, 62' N, 75° 27, 27' W); RESULTADOS: Fluxos de seston na barragem de um reservatório tropical Colombiano. Neste estudo os fluxos de sólidos totais apresentaram um valor médio de 4540 g m-2 d-1 com um intervalo entre 229 e 18573 g m-2 d-1, sendo a fra o fixa e suspensa a maior parte dos sólidos totais. Foi evidenciado que os maiores fluxos apresentaram-se entre a quarta e a quinta armadilha (as mais próximas ao fundo), devido aos fluxos hipolimnéticos que contêm materiais dos afluentes e material ressuspenso. Por isso as primeiras três armadilhas recolheram partículas que provem da coluna d'água sem avaliar o efeito real da ressuspens o. Em algumas amostragens a mineraliza o entre a terceira e a q
Quality versus Quantity  [cached]
Daniel M. Stamm
Nonpartisan Education Review , 2011,
Abstract: This essay compares American and Asian education and illustrates how quantity is chosen over quality in the U.S. in the areas of teacher training, research in education, curriculum and textbook design, and the level of education given highest priority. After demonstrating that Japanese teacher-conducted classroom research (lesson study) hasresulted in more practical, higher quality curriculum, textbooks, and teachers’ manuals, it address the objections to the use of those materials in the United States to improve teacher training and student achievement.
Quality versus quantity in scientific impact  [PDF]
Jasleen Kaur,Emilio Ferrara,Filippo Menczer,Alessandro Flammini,Filippo Radicchi
Computer Science , 2014, DOI: 10.1016/j.joi.2015.07.008
Abstract: Citation metrics are becoming pervasive in the quantitative evaluation of scholars, journals and institutions. More then ever before, hiring, promotion, and funding decisions rely on a variety of impact metrics that cannot disentangle quality from quantity of scientific output, and are biased by factors such as discipline and academic age. Biases affecting the evaluation of single papers are compounded when one aggregates citation-based metrics across an entire publication record. It is not trivial to compare the quality of two scholars that during their careers have published at different rates in different disciplines in different periods of time. We propose a novel solution based on the generation of a statistical baseline specifically tailored on the academic profile of each researcher. Our method can decouple the roles of quantity and quality of publications to explain how a certain level of impact is achieved. The method is flexible enough to allow for the evaluation of, and fair comparison among, arbitrary collections of papers --- scholar publication records, journals, and entire institutions; and can be extended to simultaneously suppresses any source of bias. We show that our method can capture the quality of the work of Nobel laureates irrespective of number of publications, academic age, and discipline, even when traditional metrics indicate low impact in absolute terms. We further apply our methodology to almost a million scholars and over six thousand journals to measure the impact that cannot be explained by the volume of publications alone.
Effective Supervision Strategies in Improving the Quality and Quantity of Research
Mohammad Syuhaimi Ab-Rahman,Nor Sha`adah Roslani,Shahrom Md Zain,Ahmad Kamal Ariffin Mohd Ihsan,Azami Zahrim,Mohd Jailani Mohd Nor,Mohd Fauzi Mohd Zain,Afiq Hipni,Nurfarah Liza Ramli,Muhammad Fadhil Che Sukarna,Iszan Hana Kaharudin
International Business Management , 2012, DOI: 10.3923/ibm.2011.312.318
Abstract: The criteria for evaluation a Research University (RU) that contribute the highest possible ranking are the quality and quantity of research. Quantity and quality refers to the strength of research in terms of the energetic nature of that research, financial assistance in the form of grants and research output. These aspects are achieved through proper and effective supervision. Effective supervision ensures that research runs smoothly and that it can also have an impact on research excellence. Effective supervision with the proper from the research team leader will be met with spirit by the student body and will lead to robust productivity. This study describes two elements of motivation, supervision and guidance and describes effective monitoring to improve both the quality and quantity of the research. Quality and quantity of research is a particular focused of the current issue of this journal and is an important topic in higher education in Malaysia.
Quality or Quantity: A Statement for Teacher Training in Turkey
Ali AZAR
Yüksek??retim ve Bilim Dergisi , 2011,
Abstract: Developed countries are initiating and implementing effective and appropriate technics in the field of teacher training. In Turkey, much research has been done in order to determine the qualification of teachers and, by this way, to train qualified teachers. Ministry of Education, Turkish Council of Higher Education, Faculties of Education and Faculties of Sciences have cooperated some certification systems, however, the research which is not supported by preliminary studies but exposured to political coercions lowered the quality of education. Besides, quantity is increased by pedagogical formation programs. In this study, Turkish teacher training system is analyzed with respect to quantity and quality.
Consumer-Resource Dynamics: Quantity, Quality, and Allocation  [PDF]
Wayne M. Getz,Norman Owen-Smith
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0014539
Abstract: The dominant paradigm for modeling the complexities of interacting populations and food webs is a system of coupled ordinary differential equations in which the state of each species, population, or functional trophic group is represented by an aggregated numbers-density or biomass-density variable. Here, using the metaphysiological approach to model consumer-resource interactions, we formulate a two-state paradigm that represents each population or group in a food web in terms of both its quantity and quality.
Effects of Quantity of Salt and Drying on the Quality of Locust Beans
O. Awogbemi,I.O. Ogunleye
Journal of Engineering and Applied Sciences , 2012,
Abstract: This research work investigated effects of quantity of salt and drying on the quality of 80 g sample of locust beans. Three categories of sample i.e., Non-salted, 5 g salted and 10 g salted, were analysed using the Direct Sunlight method of drying. After drying for 5 days, proximate and microbial analysis showed that the samples still retain most of their nutritional components and therefore fit for human consumption. Investigation also showed that salted sample is more nutritional than non salted sample as it contains 67.65% of protein as against 66.82% protein in the non-salted sample. After 5 days of drying, the non-salted sample had a microbial load of 1.02 107 cfu g 1as against the 1.42 105 cfu g 1 of the salted sample. The drying rate analysis also revealed that the non-salted sample has the fastest drying rate followed by 5 g-salted sample, with the 10 g salted sample having the least drying rate. At the end of the 3rd day of drying, the non-salted sample weighed 32 g; the 5 g sample weighed 36 g while, the10 g sample weighed 44 g.
The influence of lactation on the quantity and quality of cashmere production  [cached]
Raffaele Celi,Adriana Di Trana,Pietro Celi
Italian Journal of Animal Science , 2010, DOI: 10.4081/ijas.2002.79
Abstract: The aim of this study was to investigate the influence of lactation on cashmere production. Two groups of cashmere bearing goats, aged between 2 and 3 years, were used in this study. The control group included 12 non-lactating, non-pregnant subjects. The experimental group was made up of 12 goats that had given birth to twins or triplets and that had begun lactating in the second half of May. Lactation therefore had begun approximately 45 days prior to the beginning of the emergence of fibre on the body surface. Live weight was not affected by the physiological state under consideration. The decrease observed in January is too remote to have been an effect of lactation. One likely explanation is that after shearing the animals were obliged to use their body reserves for thermoregulation. Prolactin concentration was higher at the beginning of the study in both groups and it was not influenced by lactation. Albeit with a varied intensity, secondary follicles were found to be active during the entire trial period but activ- ity never reached 100% in either group. Lactation significantly suppressed the percentage of secondary follicle activity and this was more evident from June to September. Fibre length and diameter did not differ between the two groups, so lactation did not affect fibre dimensions. The period of growth was shorter in lactating goats (184 vs 226 d). This did not make a difference in fibre length in so much as the lactating goats manifested a higher daily aver- age growth rate (0.27 ± 0.03 vs 0.20 ± 0.03 mm/d; P lesser than 0.05) which compensated for the shorter period of growth. Lactation caused a decrease in productivity of an insignificant nature, therefore we hold that the negative effect of lactation on cashmere production does not depend upon the physiological status as such but, most probably, upon the level of productivity and the degree to which the lactation and fibre growth cycles overlap.
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