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Search Results: 1 - 10 of 2140 matches for " biology "
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Comportamento da tiririca (Cyperus rotundus) sob diferentes níveis de aduba??o fosfatada e de sombreamento
Nemoto, Marta C.M.;Alves, Pedro L.C.A.;Pitelli, Robinson A.;Nemoto, Luiz R.P.;
Planta Daninha , 1995, DOI: 10.1590/S0100-83581995000100009
Abstract: this research was carried out under greenhouse conditions at the college of agriculture, campus of jaboticabal, unesp, with the objective of studying the effects of different levels of phosphoric fertilization (0, 33.5, 67.0 and 100.5 ppm p2o5) and shading levels (0, 30, 50 and 70% of light interception) on some growth parameters of purple nutsedge (cyperus rotundus). the tubers emerged were placed (in numbers of 4) in plastic pots containing three liters of dark red latossoil (soil), medium texture, being previously screened. the experiment was land out in a completely randomized design with four replications. the results showed the detrimental effect of shading on purple nutsedge development; at a level of 30% shading there was a reduction in plant density, mainly due to a reduction in the number of bulds and tubers. as a consequence there was a reduction in the dry matter accumulation in the subterranean parts (bulbs, tubers and roots), causing na increase in the ratios pa/b+t+r and b+t/r. phosphoric fertilization, however, increased the growth parameters of the species, mainly in the development of the pa by na increase in the number and dry matter accumulation.
A review of life history pathways in Bryopsis
Marina Morabito,Gaetano M. Gargiulo,Giusi Genovese
Atti della Accademia Peloritana dei Pericolanti : Classe di Scienze Fisiche, Matematiche e Naturali , 2010,
Abstract: The genus Bryopsis comprises siphonous green algae widely distributed from tropical to polar seas. Despite the early reports on the simplicity of its life history, subsequent culture observations showed variety of life history patterns, even within a single species. Karyological data and reports on DNA quantification led to somewhat contradictory conclusions about the ploidy level of the two life history phases and about the moment of meiosis. Long term observations on Mediterranean species highlighted new alternatives in recycling of the two morphological phases. Looking at all published experimental data, we summarize all life history pathways of Bryopsis species.
Systems Biology: The take, input, vision, concerns and hopes  [PDF]
Graeme Tucker
Journal of Biomedical Science and Engineering (JBiSE) , 2009, DOI: 10.4236/jbise.2009.22014
Abstract: Systems Biology is a relatively new branch of biology that brings together an interdisciplinary team of scientist, computer engineers and mathematicians. Biomedicine can gain much from the input of Systems Biology. The object and aims of this article centre on clarification and direction for Systems Biology, notably in regard to human health and disease.
Human endogenous retroviruses: Their possible role in the molecular etiology of the schizophrenia  [PDF]
Raúl Alelú-Paz, Ignacio Iturrieta-Zuazo
Open Journal of Genetics (OJGen) , 2012, DOI: 10.4236/ojgen.2012.21009
Abstract: Human endogenous retroviruses (HERVs) represent footprints of previous retroviral infections. They are integrated within the human germ line and constitute approximately 8% of our genome. They have the potential to harm, given their capacity to alter the cellular metabolism, and could be involved in various pathological processes. This revision intends to highlight the importance of HERVs in health and disease, and the increasing interest of the scientific community in their biology. In this overview, we will present a brief summary of the structure and physiological function of HERVs and an analysis of their role in schizophrenia, a paradigm of mental illness, particularly stressing the importance of HERV research to explore the more basic mechanisms disrupted in this psychiatric condition.
Pedagogy of Creative Drama in Biology  [PDF]
Arzu Saka, Jazlin Ebenezer, Ilknur ?ak?r, Ahmet Zeki Saka
Open Journal of Social Sciences (JSS) , 2016, DOI: 10.4236/jss.2016.43024
Abstract: Creative drama grants students not only an opportunity to display their thoughts physically, orally and written but also enables them to interpret the expressions of peers. Characteristic of learning through creative drama is the development of shared meaning through the social construction of knowledge. The primary purpose of this study is to develop seventh-grade students’ conceptual understanding of some genetic concepts, attitudes toward biology learning and awareness of forensic science. The pedagogy of creative drama consisted of determining blood types and differences in human fingerprints. Twenty students took part in this study. Data sources consisted of student journaling, classroom observations, students’ responses to attitude survey and subject evaluation forms. Students learned that within the scope of creative drama activities, how the blood group determination and the cause of people’s fingerprints were separate from each other. In everyday life, they realized how important biology is, especially in criminal work. Changes in students’ attitudes toward biology indicated a positive direction because of the extraordinary teaching method. All of the participants contribute the creative drama activity keenly. Students’ attitudes toward the pedagogy of creative drama suggest that students should be approached with this sort of learning at an early age.
Extending cell cycle synchrony and deconvolving population effects in budding yeast through an analysis of volume growth with a structured Leslie model  [PDF]
Chris C. Stowers, Asmita M. Boczko
Journal of Biomedical Science and Engineering (JBiSE) , 2010, DOI: 10.4236/jbise.2010.310129
Abstract: Budding yeast are a fundamental organism at the center of systems biology research. Understanding the physiology and kinetics of their growth and division is fundamental to the design of models of gene regulation and the interpretation of experimental measurements. We have developed a Leslie model with structured volume and age classes to understand population growth and cell cycle synchrony in budding yeast. The model exhibits broad agreement with a variety of experimental data. The model is easily annotated with volume milestones and cell cycle phases and at least three distinct goals are realizable: 1) One can investigate how any single cell property manifests itself at the population level. 2) One can deconvolve observed population averages into individual cell signals structured by volume and age. 3) One can investigate controllability of the population dynamics. We focus on the latter question. Our model was initially designed to answer the question: Can continuous volume filtration extend synchrony? To date, most general experimental methods can produce an initially synchronous population whose synchrony decays rapidly over three or four cell cycles. Our model predicts that continuous volume filtration can extend this maintenance of synchrony by an order of magnitude. Our data inform the development of simple fluidic devices to extend synchrony in continuous culture at all scales from nanophysiometers to bioreactors.
Preliminary Investigation on Flowering and Fruiting Pattern in a Plantation Grown Afzelia africana Sm Stand in Umuahia, Nigeria  [PDF]
Joseph O. Ariwaodo, Joy L. Harry-Asobara
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.61025
Abstract: Research work on the improvement and breeding of indigenous hardwood species in Nigeria started about four decades ago. Such studies prove to be fruitful in planning various conservative programme specific to different habitats. The present preliminary study focuses on the flowering and fruiting pattern of a 5 year old Afzelia africana artificial forest at Eastern Research Station, Umuahia, Abia State, Nigeria. The parameters observed were phenology, flowering intensity, floral biology, fruit set and floral visitors. Flowering was first observed in 2012 (three years after planting) and subsequently in 2014 (five years after planting), although no fruit was set until 2014. All the processes of flowering to fruiting took place between January to August, with flowering peak occurring in March. The flowering intensity was very low, ranging among 286, 138, and 54, with a very low flower to fruit ratio. It is presumed that the relative young age of the trees and reduced population size amongst other probable factors may have accounted for this observation. This study is the first record of flowering and fruiting pattern of this species at plantation level in Nigeria. By late July/August, matured fruits were ready for harvest.
Studies on Vegetative and Reproductive Ecology of Paris polyphylla Smith: A Vulnerable Medicinal Plant  [PDF]
Chitta Ranjan Deb, Sakutemsu L. Jamir, Nangshimeren Sakutemsu Jamir
American Journal of Plant Sciences (AJPS) , 2015, DOI: 10.4236/ajps.2015.616258
Abstract: Paris polyphylla Smith is an important medicinal plant that is considered vulnerable in many parts of the world. The species exhibits poor adaptability to changed environment and susceptible to climatic conditions for reproductive vigor. During the present study the species was studied in four different natural niches as well as synthetic habitats to check the adaptability to artificial conditions, its morphological and physiological characters and its interaction in its community so that conservation strategies could be worked out. The present study indicates that P. polyphylla exhibits healthy growth as well as reproduction in undisturbed area with canopy covers over 80%. The plant grows in well-drained rich humus soil and grows well with certain key associated species such as Quercus species, Taxus baccata, Aconitum species, Eupatorium adenophorum, Smilax species etc. Many plants were non-flowering and more than 60% were found non-flowering in its habitat during its flowering season in any particular year. There are clear morphological changes as the flowers stages from pre-fertilization to post-fertilization. Arrangement of anthers in two whorls shows a distinct and unique floral display. Light is an important factor during seed setting and less than 50% shade lowers the seed productivity very significantly. Predators such as slugs and snails are found on the plant. Urgent conservation and new innovative ways are necessary to propagate this economically important plant to ensure its continuity.
Phytosociology with Other Characteristic Biologically and Ecologically of Plant in Palestine  [PDF]
Jehad M. H. Ighbareyeh, A. Cano-Ortiz, Asma A. A. Suliemieh, Mohammed M. H. Ighbareyeh, E. Cano
American Journal of Plant Sciences (AJPS) , 2014, DOI: 10.4236/ajps.2014.520327

Idna, Hebron area, Palestine was subject to phytosociological study through the period from March to May 2013; this area has a characteristic dry, arid, semi-arid and very little of sub-humid and locates between Mediterranean, Negev and Sinai regions. We took 237 samples of different species plants from Idna village; the absence of phytosociological studies on the area led us to run a statistical treatment on the 237 woody plant inventories. Moreover, the inventories were made following Braun-Blanquet 1979; we transformed the Braun-Blanquet species abundance-dominance values into those of Van der Maarel 1979. In the statistical treatment we obtained two large groups in the cluster: group (A), representing forests, copses and high shrublands influenced by climate (climatophilous); and group (B), representing Tamarix copses which are influenced by edaphohygrophilic. Working a great interest for Palestine. Due to the lack of phytosociological studies in this country. For the first time gets to sample and characterize the phytosociological methodology woody plant communities. The objective of this study is to obtain bioclimatic indicators to trigger sustainable agricultural development. We propose eight association plant communities such as ASL1 = association of woody plants (association one)Pistacio palaestinae-Quercetum lokii; ASL2Capparido sinaicae-Ceratonietum siliquae

Paraclinical, Therapeutic and Evolutionary Profile of Osteoarticular Tuberculosis: A Report about 550 Cases in Abidjan  [PDF]
Mohamed Diomandé, Fulgence Kaboré, Ehaulier Soh Christian Louis Kouakou, Mariam Gbané-Koné, Abidou Kawélé Coulibaly, Kouassi Jean Mermoz Djaha, Baly Ouattara, Edmond Eti, Jean Claude Daboiko, Marcel N’zué Kouakou
Open Journal of Rheumatology and Autoimmune Diseases (OJRA) , 2015, DOI: 10.4236/ojra.2015.54021
Abstract: Objective: To describe paraclinical, therapeutic and evolutionary aspects of osteoarticular tuberculosis in Abidjan. Materials and Method: We realized a descriptive retrospective study carried out in the Rheumatology Department of the University Hospital Center of Cocody in Abidjan about 550 patients over a period of 10 years from January 2004 to December 2013. The paraclinical, therapeutic and evolutionary data had interested us. Results: Osteoarticular tuberculosis represented 12.13% of 4531 rheumatic diseases identified during the study period. The tuberculin skin test was positive in 78.49% of cases. An inflammatory syndrome was present with erythrocyte sedimentation rate and C-reactive protein respectively into 69.45% and 76.54% of cases. The research of Mycobacterium tuberculosis was realized into 176 of cases which 50% was positive. Polymerase chain reaction and biopsy of tissue were performed respectively in 8 and 6 cases. Plain radiography (89.82%) and computed tomography (83.63%) were the most realized imaging. Computed tomography has contributed for the diagnostic in 99.78% of cases. The majority of our patients (82.91%) received anti-tuberculous treatment which consisted of two months of combination of rifampicin (R), isoniazid (H), pyrazinamide (Z) and Ethambutol (E) (2RHZE), followed by 10 months of rifampicin (R) and isoniazid (H) (10 RH). The outcome in patients on this treatment was favorable in 528 cases (96%). Conclusion: This study revealed that the research of Mycobacterium tuberculosis was often realized and positive. On the contrary, polymerase chain reaction and biopsy of tissue were rarely performed. The main imaging is computed tomography. Our protocol of treatment is effective.
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