bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative analysis of genetic diversity among the maize inbred lines (Zea mays L.) obtained by RAPD and SSR markers
Authors: Souza Silvia Graciele Hülse de , Carpentieri-Pípolo Valéria , Ruas Claudete de Fátima , Carvalho Valdemar de Paula , Ruas Paulo Maurício , Gerage Antônio Carlos
Published: April 2008

The RAPD and SSR markers were used to compare the genetic diversity among the 16 maize inbred lines. Twenty-two primers were used in the RAPD reactions, resulting in the amplification of 265 fragments, while 16 pairs of SSR primers resulted in 75 fragments. The similarity based on Dice coefficient for the RAPD ranged from 53 to 84% and for the SSR from 11 to 82%. The dendrogram obtained by the RAPD showed five groups, while dendrogram obtained by the SSR showed three groups and one isolated line. The association constructed from the markers and the principal coordinate’s analysis separated lines into two groups according to endosperm color, either orange or yellow. The RAPD were effective to validate pedigree data, while the SSR were effective to recognize the differences between the quantitative characters. Because they assess the distinct regions of the genome, the selection of one or other marker would depend on the characteristics of the material used and the objectives of the project.
Effects of storage and solvent type in a lipophylic chemical profile of the seaweed Dictyota menstrualis
Authors: Cavalcanti Diana Negrão , Gomes Marcelo Augusto Vasconcelos , Pinto Angelo Cunha , Rezende Claudia Moraes de , Pereira Renato Crespo , Teixeira Valéria Laneuville
Published: April 2008

Crude extracts from specimens of the brown seaweed Dictyota menstrualis, known to produce diterpenes as their major secondary metabolites, were analyzed according to storage procedures before extraction, and the solvent types used to obtain the crude extracts. The specimens of D. menstrualis were submitted to three types of storage procedures, such as wet, dry, and frozen and were extracted with a mixture of dichloromethane:methanol (2:1) and acetone. Qualitative differences were not observed by GC/MS analyses of all crude extracts containing mainly the diterpenes pachydictyol A (I), 6-hydroxy-dichotoma-3,14-diene-1,17-dial (II), 6-hydroxy-2,7-cycloxenia-3,14-diene-1,17-dial (III), and 6-acetoxy-dichotoma-3,14-diene-1,17-dial (IV). The most efficient and selective extraction of the compounds with intermediate polarity produced by D. menstrualis was obtained using acetone, but with less mass production. In general, the storage procedures produced very similar results, but the frozen samples furnished low amount of total diterpenes. According to these results on chemical analysis of crude extracts of seaweeds, the choice of solvent to extraction should be considered as important aspect to better screening bioactive compounds.
Acampamento educacional para crianças asmáticas
Authors: Costa Maria do Rosario da Silva Ramos , Oliveira Maria Alenita , Santoro Ilka Lopes , Juliano Yara , Pinto José Rosado , Fernandes Ana Luisa Godoy
Published: April 2008

OBJETIVO: Avaliar o impacto de um programa de acampamento educacional para crianças asmáticas, com duração de cinco dias, em termos da melhora do nível de conhecimento sobre a asma e da melhora da destreza no uso de medicação inalatória e na execução de exercícios físicos. MÉTODOS: Diariamente, as crianças recebiam 20 min de educação interativa, a técnica do uso do inalador dosimetrado era revista, realizavam-se duas medidas de pico de fluxo, e as crianças realizavam atividades físicas que incluíam exercícios respiratórios e de relaxamento. Um questionário que avaliava o conhecimento das crianças sobre a asma, os desencadeadores da crise, a medicação, os conceitos errôneos e o uso de espaçadores foi aplicado antes e após a intervenção. O uso correto da medicação inalatória e os sintomas relacionados às atividades físicas também foram avaliados antes e após a intervenção. RESULTADOS: Um total de 37 crianças asmáticas, 15 meninas e 22 meninos (idade de 8 a 10 anos), foi avaliado. Desse total, 25% apresentaram melhora do nível de conhecimento específico sobre a asma, a qual foi demonstrada pelo maior número de acertos em três das doze questões analisadas (p < 0,05). Os escores de dispnéia relacionada à atividade física diminuíram significativamente após a intervenção (p < 0,05). A habilidade para usar corretamente a medicação inalatória foi significativamente maior após a intervenção (p < 0,05). CONCLUSÕES: O programa de acampamento educacional pode aumentar o conhecimento sobre questões específicas, encorajar a participação em atividades físicas e melhorar a habilidade das crianças no manejo da asma.
Prevalência de transtornos emocionais e comportamentais em adolescentes com asma
Authors: Alvim Cristina Gonçalves , Ricas Janete , Camargos Paulo Augusto Moreira , Lasmar Laura Maria Belizário de Lima Facury , Andrade Cláudia Ribeiro de , Ibiapina Cássio da Cunha
Published: April 2008

OBJETIVO: Determinar a prevalência de transtornos emocionais e comportamentais em adolescentes com asma e compará-la com a prevalência em adolescentes sem asma. MÉTODOS: Estudo transversal através de um questionário de transtornos psicológicos (Strengths and Difficulties Questionnaire) aplicado a adolescentes de 14 a 16 anos, com e sem asma, selecionados aleatoriamente em escolas municipais de Belo Horizonte (MG) Brasil. RESULTADOS: A prevalência de transtornos emocionais e comportamentais em adolescentes com e sem asma foi 20,4% (IC95%: 14,5-27,8%) e 9% (IC95%: 6,1-12,8%), respectivamente. Entre os adolescentes com asma, 56,6% (IC95%: 48,3-64,5%) apresentavam escores dentro da faixa de normalidade e 23% (IC95%: 16,8-30,7%), valores limítrofes. Entre os que não tinham asma, 75% (IC95%: 69,7-79,6%) apresentavam escores normais e 16% (IC95%: 12,2-20,7%), limítrofes. A mediana no escore total do questionário foi 14 nos portadores de asma e 12 nos sem asma (p < 0,01). Na análise multivariada (regressão logística), controlado para variáveis socioeconômicas, permaneceram significativas as associações entre transtornos emocionais e comportamentais e as seguintes variáveis: sexo feminino (OR = 1,98; IC95%: 1,10-3,56, p = 0,02), e ter asma (OR = 2,66; IC95%: 1,52-4,64, p = 0,001). CONCLUSÕES: A prevalência de transtornos emocionais e comportamentais em adolescentes portadores de asma é significativamente maior do que naqueles que não tem asma, reforçando a necessidade de uma abordagem interdisciplinar e sistêmica.
Towards a deeper and broader ecological footprint
Authors: Peters G. M. , Sack F. , Lenzen M. , Lundie S. , Gellego B.
Published: April 2008

A revised methodology for calculating ecological footprints is proposed. The method considers anthropogenic disturbances at a finer level of geographical desegregation than previous methods; instead of a single national land area it considers 1408 smaller regions within Australia. It also addresses a previous gap in disturbance-based ecological footprint calculation, that is, the exclusion of ecotoxic emissions. The method is described and illustrated using a case study. The resulting ecological footprint is larger than previous calculations, but it avoids a current methodological problem in which the energy used to treat exhaust gases or wastewaters increases the ecological footprint of communities without any corresponding benefit associated with reduced emissions to the environment.
Transforming impact assessment for sustainable development and poverty eradication
Authors: Downs T. J.
Published: April 2008

Sustainable development and poverty eradication are global challenges that require a systematic, transformative approach for action on the ground, with enhanced environmental impact assessment (EIA) at its core. Traditional EIA has been criticised for being a top-down regulatory method biased in favour of the sponsor of a development action. The purposes of this paper are to describe how to transform EIA into a process that enables sustainable development and poverty eradication, and to stimulate much-needed dialogue among engineers, scientists and policy makers. The paper argues for the synthesis of four components to create a new approach: (a) an adaptive social learning process at the core for multi-stakeholder assessment, planning, implementation and monitoring; (b) a trans-disciplinary, knowledge-partnership, systems-based approach to assessment that identifies priority problems and drivers using risk and vulnerability theory; (c) multi-criteria sustainability assessment of alternative solutions that makes socio-political, cultural, economic and ecological trade-offs transparent; and (d) integrated capacity building to sustain the target solution. Deductive reasoning based on empirical evidence from case studies and a literature review supports the argument.
Trialling Ceequal on a London railway embankment
Authors: Lendrum E. Campbell , Feris J.
Published: April 2008

Environmental professionals and engineers working alongside each other on civil engineering projects often face the challenge of differing expectations regarding measurement and management of performance. Engineers expect precise measurements, while environmental management has not historically had rigorous and comparable mechanisms for measuring environmental performance. On civil engineering projects, the measurement of environmental performance often consists of attainment of certification to ISO 14001 and a number of unverified internal metrics that vary from project to project. The problem of how environmental performance can be credibly measured and then improved on a programme of civil engineering projects was one faced by the authors while working for Metronet Rail. This paper reports on the use of the civil engineering environmental quality assessment and awards scheme (Ceequal) to benchmark environmental management on an embankment stabilisation project on London Underground's Central line. It outlines the basis behind the assessment system and how it has been used to identify areas for improvement in environmental management in a programme of projects.
Application of sustainability indicators in decision-making processes for urban regeneration projects
Authors: Hunt D. V. , Lombardi D. R. , Rogers C. D. , Jefferson I.
Published: April 2008

Birmingham Eastside, an area of 170 ha, is located to the eastern side of Birmingham's city centre in the UK. Over a 10-year period this once-deprived inner city area is being regenerated through public and private finance estimated at £6 billion. The regeneration scheme is bringing about changes to the local environment, economy and society. The key players (e.g. landowners, developers and planners) involved in the decision-making processes for Eastside have the power to see that these changes are brought about in a more sustainable manner. To achieve this it is necessary to assess in which direction the development should go, and to provide benchmarks for implementing and measuring sustainable changes along the way. The process can be facilitated by the use of sustainability indicators, of which there are many. This paper outlines a variety of sustainability indicators (e.g. Spear, Breeam, sustainability checklists and other benchmarks), including those used within the decision-making processes for Eastside. In particular, it details those indicators operating at city level, quarter level and then individual development site level. Several case study sites are included (Masshouse, City Park Gate, the learning and leisure quarter, the new technology institute and Warwick Bar). The paper discusses the role of indicators in achieving a more sustainable development (SD). The development timeline framework (DTF) is used to analyse how and when indicators have formed an integral part of the decision-making process for various sites in Eastside. The responsibility for implementing SD and the role of participation are discussed and generic lessons learned for the application of indicators, including aspects of timing, are set out.
Soil improvement by internally reinforced stone columns
Authors: Ayadat T. , Hanna A. M. , Hamitouche A.
Published: April 2008

Granular columns have been used as an effective technique for improving the engineering behaviour of soft clays and loose sand deposits. This paper presents the results of an experimental investigation on sand columns internally reinforced with horizontal wire meshes made of plastic, steel and aluminium materials. Loading tests were performed on prototype reinforced sand columns in a stress-controlled chamber that contained normally consolidated clay. The objective of this investigation was to establish the load-carrying capacity of these columns in light of the presence and intensity of the reinforcement. The performance of the reinforced sand mass was examined, by direct shear testing, in terms of angle of shearing resistance, strains to peak strength, bearing ratio, and brittleness of the system post-peak. A theoretical model is proposed to predict the load-carrying capacity of these columns. The values predicted by the proposed theory compared well with the results of the present experimental investigation as well as those available in the literature. A design procedure is presented for practitioners.
Eccentricity effect on a footing supported by a stone column
Authors: Sadek M. , Shahrour I.
Published: April 2008

This paper includes analysis of the response to vertical loading of a single footing supported by a stone column. It mainly concerns the influence of footing eccentricity with regard to the stone column on the behaviour of the footing-stone column system. An eccentricity of e = 20 cm is generally accepted in engineering practice. Analyses are carried out using three-dimensional, elastoplastic finite-element modelling. Computations for different eccentricities show that the footing eccentricity slightly affects the vertical stiffness and bearing capacity of the footing-stone column system.
Ground improvement by small-diameter timber piles
Authors: Ghosh S. , Mukherjee S. , Sahu R. B. , Ghosh A. , Som N.
Published: April 2008

Geotechnical engineers often encounter problems in designing foundations of structures on soft clayey soil. There may be a need for ground treatment to improve the bearing capacity of the soil. In the case of mediumrise buildings in and around Kolkata, a common practice has been to provide closely spaced 150–200 mm diameter timber piles of 5–6 m length. These timber piles have helped the structures to stand on soft clayey soil with little or negligible distress over the years. The present investigation includes the study of bearing capacity and settlement behaviour of model footings resting on small-diameter timber piles. Model footings were tested on an artificially consolidated kaolin bed with small-diameter timber piles inserted into the clay bed. To supplement the results of laboratory model tests, prototype tests were also carried out in the field. In order to obtain a parametric study, the length and spacing of timber piles as well as the extent of piles around and below the footings were varied. The study shows that the use of small-diameter timber piles produced beneficial effects for pile lengths greater than the width of the footing. An appreciable effect on bearing capacity is observed when area ratio (i.e. pile area/soil influence area) becomes more than 10%. The extent of these timber piles beyond twice the width of the footing results in a marginal increase in the bearing capacity. Considerable reduction in settlement occurred when timber piles were used. A semi-empirical method of calculating settlement has been presented for foundations with small-diameter timber piles.
Effects of beam—column depth ratio on joint seismic behaviour
Authors: Wong H. F. , Kuang J. S.
Published: April 2008

Full-scale reinforced concrete (RC) exterior beam–column joints, which are fabricated to simulate those in as-built RC frame buildings designed to BS 8110, are tested under reversed cyclic loading. The seismic behaviour of these non-seismically designed joints is investigated. Particular emphasis is given to the effects of the beam–column depth ratio, column longitudinal reinforcement and stirrups in joints on the seismic performance and shear strength of the joints. It is shown that beam–column depth ratio has a significant effect on the shear strength and ductility of beam–column joints, while intermediate longitudinal reinforcement may be used to enhance the shear capacity and improve the hysteretic behaviour of beam–column joints, and links placed in beam–column joint cores can effectively improve the seismic behaviour and enhance the joint shear strength. Test results are compared with those predicted by three seismic design codes (ACI-318, NZS 3101 and Eurocode 8) and two non-seismic design codes (BS 8110 and Eurocode 2). It has been shown that member sizing and reinforcement detailing have significant effects on the shear capacity and seismic behaviour of exterior beam–column joints. In general, present seismic and non-seismic design codes do not accurately predict the shear strength of the non-seismically detailed joints, while BS 8110 may provide relatively better predictions than others in these particular cases.
Aggregation and surface properties of iron oxide nanoparticles: Influence of ph and natural organic matter
Authors: Baalousha Mohammed , Manciulea Adriana , Cumberland Susan , Kendall Kevin , Lead Jamie R
Published: April 2008

The interactions between unpurified manufactured nanoparticles (NPs; iron oxide NPs, ∼7 nm) and standard Suwannee River humic acid (SRHA) were investigated under a range of environmentally relevant conditions. At low pH, approximately 35% of the total iron was in the dissolved phase (<1 kDa), present from the initial synthesis, whereas at pH more than 4, this concentration was negligible because of the formation of new particles via hydrolysis. Dynamic light scattering results indicated that extensive aggregation of NPs began at approximately pH 5 to 6 and reached a maximum at approximately pH 8.5, whereas with added SRHA, aggregation was shifted to lower pH values of 4 to 5 and was affected by SRHA concentration. Aggregation could be explained mainly by charge neutralization. Further, more detailed investigations by flow field-flow fractionation and transmission-electron microscopy were performed under a more restricted set of conditions (pH 2–6) to examine the aggregation process. Results indicated the formation of SRHA surface coating on iron oxide NPs of approximately 1 nm and the increase in thickness of this coating with the increase of SRHA concentration. Iron oxide NPs were shown to form increasingly large aggregates with increases in both pH (from 2 to 6) and SRHA concentration (from 0 to 25 mg/L). The structure and aggregation mechanism of these aggregates were found to be both pH and SRHA concentration dependent, with open, porous aggregates in the absence of SRHA and compact aggregates in the presence of SRHA.
Finnish trends in phosphorus balances and soil test phosphorus
Authors: UUSITALO R. , TURTOLA E. , GRÖNROOS J.
Published: April 2008

Soil test phosphorus (P) concentration has a major influence on the dissolved P concentration in runoff from agricultural soils. Thus, trends in soil test P partly determine the development of pollution potential of agricultural activities. We reviewed the changes of soil test P and P balances in Finnish agriculture, and assessed the current setting of P loss potential after two Agri-Environmental Programs. Phosphorus balance of the Finnish agriculture has decreased from +35 kg ha1 of the 1980s to about +8 kg P ha1 today. As a consequence, the 50-yr upward trend in soil test P concentrations has probably levelled out in the late 1990s, as suggested by sampling of about 1600 fields and by a modelling exercise. For the majority of our agricultural soils, soil test P concentrations are currently at a level at which annual P fertilization is unlikely to give measurable yield responses. Soils that benefit from annual P applications are more often found in farms specialized in cereal production, whereas farms specialized in non-cereal plant production and animal production have higher soil test P concentrations. An imbalance in P cycling between plant (feed) and animal production is obvious, and regional imbalances are a result of concentration of animal farms in some parts of the country. A major concern in future will be the fate of manure P in those regions where animal production intensity is further increasing.;
Surface runoff, subsurface drainflow and soil erosion as affected by tillage in a clayey Finnish soil
Authors: TURTOLA E. , ALAKUKKU L. , UUSITALO R.
Published: April 2008

Conservation tillage practices were tested against autumn mouldboard ploughing for differences in physical properties of soil, surface runoff, subsurface drainflow and soil erosion. The study (1991 -2001) was performed on a gently (2%) sloping clayey soil of southern Finland, with two replicates of the tillage treatments on 0.5 ha plots. The annual shares of surface runoff of the total flow (surface runoff + subsurface drainflow) were 842% for ploughing (depth 2023 cm), 3666% for shallow autumn stubble cultivation (depth 58 cm) and 3682% for soil left untilled over winter. Surface runoff increased with decrease in the tillage intensity, and in line with the values of depressional water storage, macroporosity and saturated hydraulic conductivity. Erodibility of this gently sloping soil was at highest after autumn and spring tillage operations and decreased with time. Shallow autumn tillage produced erosion as high as mouldboard ploughing (4071700 kg ha1yr1), but 48% and 12% lower erosion levels were measured from plots left untilled in autumn, covered by grass or barley residues, respectively. Eroded soil particles moved relatively freely to the subsurface drains, which carried 3794% of the annual soil losses from the field. The study shows that even on the relatively flat clayey soils typical for southern Finland, tillage has a great influence on soil losses. The frequency of tillage needs to be reduced rather than the depth of tillage on clayey soils with poor water conductivity and structural stability if soil loss is to be diminished by conservation tillage.;
The Complexity of Orbits of Computably Enumerable Sets
Authors: Cholak Peter A. , Downey Rodney , Harrington Leo A.
Published: April 2008

The goal of this paper is to announce there is a single orbit of the c.e. sets with inclusion, ε, such that the question of membership in this orbit is complete. This result and proof have a number of nice corollaries: the Scott rank of ε is + 1; not all orbits are elementarily definable; there is no arithmetic description of all orbits of ε; for all finite α ≥ 9, there is a properly orbit (from the proof).
Scales in K(ℝ) at the end of a weak gap
Authors: Steel J. R.
Published: April 2008

In this note we shall prove

Theorem 0.1. Letbe a countably ω-iterable-mouse which satisfies AD, and [α, β] a weak gap of. Supposeis captured by mice with iteration strategies in ∣α. Let n be least such that ; then we have that believes that has the Scale Property.

This complements the work of [5] on the construction of scales of minimal complexity on sets of reals in K(ℝ). Theorem 0.1 was proved there under the stronger hypothesis that all sets definable over are determined, although without the capturing hypothesis. (See [5, Theorem 4.14].) Unfortunately, this is more determinacy than would be available as an induction hypothesis in a core model induction. The capturing hypothesis, on the other hand, is available in such a situation. Since core model inductions are one of the principal applications of the construction of optimal scales, it is important to prove 0.1 as stated.

Our proof will incorporate a number of ideas due to Woodin which figure prominently in the weak gap case of the core model induction. It relies also on the connection between scales and iteration strategies with the Dodd-Jensen property first discovered in [3]. Let be the pointclass at the beginning of the weak gap referred to in 0.1. In section 1, we use Woodin's ideas to construct a Γ-full a mouse having ω Woodin cardinals cofinal in its ordinals, together with an iteration strategy Σ which condenses well in the sense of [4, Def. 1.13]. In section 2, we construct the desired scale from and Σ.
On the consistency strength of the inner model hypothesis
Authors: Friedman Sy-David , Welch Philip , Woodin W. Hugh
Published: April 2008

The Inner Model Hypothesis (IMH) and the Strong Inner Model Hypothesis (SIMH) were introduced in [4]. In this article we establish some upper and lower bounds for their consistency strength.

We repeat the statement of the IMH, as presented in [4]. A sentence in the language of set theory is internally consistent iff it holds in some (not necessarily proper) inner model. The meaning of internal consistency depends on what inner models exist: If we enlarge the universe, it is possible that more statements become internally consistent. The Inner Model Hypothesis asserts that the universe has been maximised with respect to internal consistency:

The Inner Model Hypothesis (IMH): If a statement φ without parameters holds in an inner model of some outer model of V (i.e., in some model compatible with V), then it already holds in some inner model of V.

Equivalently: If φ is internally consistent in some outer model of V then it is already internally consistent in V. This is formalised as follows. Regard V as a countable model of Gödel-Bernays class theory, endowed with countably many sets and classes. Suppose that V* is another such model, with the same ordinals as V. Then V* is an outer model of V (V is an inner model of V*) iff the sets of V* include the sets of V and the classes of V* include the classes of V. V* is compatible with V iff V and V* have a common outer model.
Special groups whose isometry relation is a finite union of cosets
Authors: Astier Vincent
Published: April 2008

ℵ0-stable ℵ0-categorical linked quaternionic mappings are studied and are shown to correspond (in some sense) to special groups which are ℵ0-stable, ℵ0-categorical, satisfy AP(3) and have finite 2-symbol length. They are also related to special groups whose isometry relation is a finite union of cosets, which are then considered on their own, as well as their links with pseudofinite, profinite and weakly normal special groups.
Coding complete theories in Galois groups
Authors: Gray James
Published: April 2008

In this paper, I will give a new characterisation of the spaces of complete theories of pseudofinite fields and of algebraically closed fields with a generic automorphism (ACFA) in terms of the Vietoris topology on absolute Galois groups of prime fields.
Internal consistency and global co-stationarity of the ground model
Authors: Dobrinen Natasha , Friedman Sy-David
Published: April 2008

Global co-stationarity of the ground model from an ℵ2-c.c. forcing which adds a new subset of ℵ1 is internally consistent relative to an ω1-Erdős hyperstrong cardinal and a sufficiently large measurable above.
Hierarchies of forcing axioms II
Authors: Neeman Itay
Published: April 2008

A truth for λ is a pair 〈Q, ψ〉 so that Q ⊆ Hλ, ψ is a first order formula with one free variable, and there exists B ⊆ Hλ+ such that (Hλ+; ∈, B) ⊨ ψ[Q]. A cardinal λ is , indescribable just in case that for every truth 〈Q, ψ〈 for λ, there exists < λ so that is a cardinal and 〈Q ∩ , ψ) is a truth for . More generally, an interval of cardinals [κ, λ] with κ ≤ λ is indescribable if for every truth 〈Q, ψ〈 for λ, there exists , and π: → Hλ so that is a cardinal, is a truth for , and π is elementary from () into (H; ∈, κ, Q) with id.

We prove that the restriction of the proper forcing axiom to ϲ-linked posets requires a indescribable cardinal in L, and that the restriction of the proper forcing axiom to ϲ+-linked posets, in a proper forcing extension of a fine structural model, requires a indescribable 1-gap [κ, κ+]. These results show that the respective forward directions obtained in Hierarchies of Forcing Axioms I by Neeman and Schimmerling are optimal.
On the structure of the Medvedev lattice
Authors: Terwijn Sebastiaan A.
Published: April 2008

We investigate the structure of the Medvedev lattice as a partial order. We prove that every interval in the lattice is either finite, in which case it is isomorphic to a finite Boolean algebra, or contains an antichain of size . the size of the lattice itself. We also prove that it is consistent with ZFC that the lattice has chains of size . and in fact that these big chains occur in every infinite interval. We also study embeddings of lattices and algebras. We show that large Boolean algebras can be embedded into the Medvedev lattice as upper semilattices, but that a Boolean algebra can be embedded as a lattice only if it is countable. Finally we discuss which of these results hold for the closely related Muchnik lattice.
Randomness, lowness and degrees
Authors: Barmpalias George , Lewis Andrew E. M. , Soskova Mariya
Published: April 2008

We say that A ≤LRB if every B-random number is A-random. Intuitively this means that if oracle A can identify some patterns on some real γ, oracle B can also find patterns on γ. In other words, B is at least as good as A for this purpose. We study the structure of the LR degrees globally and locally (i.e., restricted to the computably enumerable degrees) and their relationship with the Turing degrees. Among other results we show that whenever ∝ is not GL2 the LR degree of ∝ bounds degrees (so that, in particular, there exist LR degrees with uncountably many predecessors) and we give sample results which demonstrate how various techniques from the theory of the c.e. degrees can be used to prove results about the c.e. LR degrees.
Generic complexity of undecidable problems
Authors: Myasnikov Alexei G. , Rybalov Alexander N.
Published: April 2008

In this paper we study generic complexity of undecidable problems. It turns out that some classical undecidable problems are, in fact, strongly undecidable, i.e., they are undecidable on every strongly generic subset of inputs. For instance, the classical Halting Problem is strongly undecidable. Moreover, we prove an analog of the Rice theorem for strongly undecidable problems, which provides plenty of examples of strongly undecidable problems. Then we show that there are natural super-undecidable problems, i.e., problem which are undecidable on every generic (not only strongly generic) subset of inputs. In particular, there are finitely presented semigroups with super-undecidable word problem. To construct strongly- and super-undecidable problems we introduce a method of generic amplification (an analog of the amplification in complexity theory). Finally, we construct absolutely undecidable problems, which stay undecidable on every non-negligible set of inputs. Their construction rests on generic immune sets.
Transfer and a supremum principle for ERNA
Authors: Impens Chris , Sanders Sam
Published: April 2008

Elementary Recursive Nonstandard Analysis, in short ERNA, is a constructive system of nonstandard analysis proposed around 1995 by Patrick Suppes and Richard Sommer, who also proved its consistency inside PRA. It is based on an earlier system developed by Rolando Chuaqui and Patrick Suppes, of which Michal Rössler and Emil Jeřábek have recently proposed a weakened version. We add a Πı-transfer principle to ERNA and prove the consistency of the extended theory inside PRA. In this extension of ERNA a Σı-supremum principle ‘up-to-infinitesimals’, and some well-known calculus results for sequences are deduced. Finally, we prove that transfer is ‘too strong’ for finitism by reconsidering Rössler and Jeřábek's conclusions.
Studies of Biologically Active Heterocycles: Synthesis, Characterization and Antimicrobial Activity of Some 2,5-Disubstituted-1,3,4-Oxadiazoles
Authors: Nagalakshmi G
Published: April 2008

1,3,4-oxadiazoles are important because of its versatile biological actions. In the present study, several 2,5-disubstituted-1,3,4-oxadiazoles (3a-o) have been synthesized by the condensation of 4-hydroxybenzohydrazide (1) with various aromatic acids (2a-o) in presence of phosphorus oxychloride. The structures of the newly synthesized compounds have been established on the basis of elemental analysis, UV, IR and 1H NMR spectral data. The synthesized compounds were screened for their in vitro growth inhibiting activity against different strains of bacteria and fungi viz., Staphylococcus aureus, Bacillus subtilis, Bacillus megaterium, Escherichia coli, Pseudomonas aeruginosa, Shigella dysenteriae, Candida albicans, Aspergillus niger and Aspergillus flavus and the results were compared with the standard antibiotics such as chloramphenicol (50?g/ml) and Griseofulvin (50?g/ml) using agar diffusion technique. Compounds 3b, 3e, 3g, 3h, 3j, 3m and 3n exhibited strong antibacterial activity and compounds 3a, 3d, 3g, 3h and 3i showed good antifungal activity.

Key words: 2,5-disubstituted-1,3,4-oxadiazoles, 4-hydroxybenzohydrazide, phosphorus oxychloride, antimicrobial evaluation, agar well diffusion method.

Dhaka Univ. J. Pharm. Sci. 6(2): 69-75, 2007 (December)
QSAR Optimization of Benzofuran and Benzothiophene Sulfono Biphenyl as Potent PTPase-1B Inhibitors
Authors: Kaushik Darpan , Khan Suroor A , Alam Ozair , Chawla Geeta , Kashedikar Satish G
Published: April 2008

Insulin resistance is associated with a defect in protein tyrosine phosphorylation in the insulin signal transduction cascade. Protein tyrosine phosphatase (PTPase) enzyme dephosphorylates the active form of insulin receptor and thus attenuates its tyrosine kinase activity, therefore the need of potent PTPase inhibitor is there with that intention the Quantitative structure-activity relationship QSAR was performed. QSAR has been established on a series of compounds of novel sulfono biphenyl analogs using SYSTAT (Version 7.0) software, for their PTPase-1B inhibitor activity, in order to understand the essential structural requirement for binding with the receptor. Among several 2D QSAR models, one for a series was selected on the basis of high correlation coefficient, least standard deviation, & high value of significance for maximum no. of subject was considered. The interpreted data signify the essentiality of Benzofuran ring in the designing of the new PTPase -1B inhibitors and any substitution on the biphenyl and sulfonyl phenyl is going to decrease its activity.

Key words: QSAR, PTPase-1B inhibitor, Sulfono biphenyl analog.

Dhaka Univ. J. Pharm. Sci. 6(2): 77-80, 2007 (December)
In vitro Measurement of Electrolytes and Nutrients Transport through Intestinal Epithelium during Cholera Toxin Induced Secretion
Authors: Parveen Seheli , Chowdhury AK Azad
Published: April 2008

Cholera toxin and other bacterial toxins can induce electrogenic chloride (Cl-) secretion in the small intestine resulting in secretory diarrhoea, when the colonic water reabsorption capacity is overwhelmed. The mechanism underlying this phenomena is that, these toxins increase intracellular cGMP and/or cAMP level through activation of guanylyl and adenylyl cyclase leading to the phosphorylation of the apical chloride channel (CFTR) and electrogenic Cl- secretion as revealed in vitro by an increase in short-circuit current reflecting an increase in electrolyte transport in the intestine. The aim of the study was to investigate the effects of D-(+) glucose on water and electrolyte movements across rat jejunum after challenging with cholera toxin and dbcAMP (a lipophilic analog of cAMP which readily crosses the basolateral membrane of small intestinal cells); and also to investigate whether the magnitude of response to D-(+) glucose was related to the extent of secretion induced by dbcAMP. The measurement of the ion transport across the unstripped rat jejunum was carried out using Ussing chambers. The response to D-(+) glucose was studied in both CT-treated and untreated tissue; the results showed no significant difference between Isc responses to D-(+) glucose in unstimulated and CT-stimulated rat jejunum (?Isc = 45.3 ± 12.9 ?A/cm2 versus 38.9 ± 13.9 ?A/cm2, n = 8), whereas, in the studies where tissues treated with dbcAMP instead of CT, results showed a small but significant difference in D-(+) glucose response affected by dbcAMP (?Isc = 12.9 ± 4.7 ?A/cm2 versus 24.0 ± 4.3 ?A/cm2, n = 8).

Key words: Electrolytes; Cholera toxin; Transport

Dhaka Univ. J. Pharm. Sci. 6(2): 81-86, 2007 (December)
Effect of Calcium Carbide on Rat Tissue
Authors: Patoare Younus , Hossain Md Iqbal , Islam Mohammad Nurul , Chowdhury Akhtarunnessa , Parveen Seheli , Hossain Md Mahboob , Hasnat Abul
Published: April 2008

To evaluate the effects of Calcium carbide (CaC2) in biological system, an in vivo study was carried out on Long Evans rats. CaC2 was administered orally once daily for one month with specific concentrations. Group- I was considered as the control group (without CaC2), Group - II, III, IV and V were the sample groups treated with CaC2 having concentration of 1g/kg, 2g/kg, 5g/kg and 10g/kg body weight respectively. The experiment was conducted to detect any cellular and molecular level changes caused by CaC2. The histopathology and isozyme assay were performed to analyze the changes in the activities of the genes affected by the free radicals released from CaC2. The molecular analysis included different isozymes namely esterase and acid phosphatase. Polyacrylamide electrophoresis of whole cell extract of control subjects and CaC2 administered rats were performed; subsequently the gels were treated with the substrates for acid phosphatase and esterase respectively. No difference was observed in the whole cell extract band pattern between the control subject and the CaC2 administered rats, which grossly indicates that the CaC2 has no effect on the expression pattern of isozymes (acid phosphatase and esterase). Histopathological analysis of liver, heart, spleen, kidney and lungs were performed to observe any change due to the administration of CaC2. Remarkable changes were observed during the histopathological study of lungs and kidney only. The histopathological analysis of kidney showed the thickening of the lining of collecting tubules with changes in cell structure while lungs were found to be increased moderately in weight, with focal areas of consolidation that was found red-brown to red.

Key words: Calcium carbide; Histopathological study; Isozymes

Dhaka Univ. J. Pharm. Sci. 6(2): 93-98, 2007 (December)
In vitro Release Kinetics of Progesterone from Biodegradable In situ Implant System
Authors: Dewan Irin , Elias-Al-Mamun Md , Jalil Reza-ul
Published: April 2008

In situ implants containing Progesterone (PRG) were prepared by using biodegradable Poly (DLlactide- co-glycolide) polymer. Dimethyl sulfoxide (DMSO) was used as an aprotic solvent in this implant formulation. This system was prepared by dissolving a water insoluble and biodegradable polymer (PLGA) in a biocompatible organic solvent (DMSO) and then the drug progesterone was added to the polymer solution to produce the drug solution. When the PLGA-PRG solution (0.5 ml) was injected subcutaneously into rat (weight 130g), the solvent dissipated into the surrounding tissue leading phase separation and subsequent coagulation of the polymer & drug to form an implant in situ. The implants were removed from the rat after one hour and stored in freezing condition. The digital photographs of the in-situ formed implants obtained after 1hour shows the evidence of the formation of the implants. Two formulations of implants were made. One contained 10% of progesterone and the other 20%. In vitro dissolution studies of progesterone was performed at static condition in ethanol-water mixture (30:70) at 37°C for 30 days. The implants of 20% progesterone loading showed about 65% release and the implants of 10% loading showed 56% release within 30 days. The release mechanism from these implants resembles closely to Higuchian pattern and first order. The release rate was found faster from the implants with higher drug loading of 20% progesterone, compared to implants of 10% drug loading.

Key words: Biodegradable; Implant; Biocompatible; Sustained Release

Dhaka Univ. J. Pharm. Sci. 6(2): 99-103, 2007 (December)
In vitro - In vivo Correlation (IVIVC) of Immediate Release (IR) Levofloxacin Tablet
Authors: Akbor Maruf Mohammad , Sultana Rebeka , Ullah Ashik , Azad Mohammad Abul Kalam , Latif AHM Mahbub , Hasnat Abul
Published: April 2008

The aim of this study was to examine the in vitro - in vivo correlation (IVIVC) of two immediate release formulations of levofloxacin 250 mg film coated tablet. In vitro release data were obtained for each formulation by using the USP apparatus II, in 0.1N HCl of pH 2.0. Twelve healthy subjects were randomly chosen for in vivo study. Blood samples were collected over 24 hour period and analyzed by validated HPLC method with UV detection to establish a correlation between in vitro release and in vivo absorption. f2 and f1 were determined for the time intervals of 5, 10, 15, 20, 25, 30, 45 and 60 minutes and the obtained values were 65.72, 77.38, 61.93, 53.75, 55.36, 58.59, 60.23 and 61.16 percent for f2 and 11.00, 4.35, 8.30, 12.15, 5.59, 1.82, 0.06 and 0.11 percent for f1 at respective time intervals. Mean dissolution times (MDT) for local and reference products were obtained at 7.69 and 9.55 minutes respectively. The values of mean absorption time (MAT) were obtained at 8.27 and 27.96 minutes for local and reference products respectively. For in vitro and in vivo correlation, level A type was also done for both products. In case of level A correlation, a non linear type of relation was established which is typical for immediate release formulations.

Key words: In vitro - In vivo correlation; Levofloxacin; Immediate release tablets; Similarity factors.

Dhaka Univ. J. Pharm. Sci. 6(2): 113-119, 2007 (December)
Antimicrobial and Cytotoxic Activities of the Crude Extracts of Hopea scaphula
Authors: Gazi Hamidur R , Kabir Selina , Rahman Mohammad S , Chowdhury AM Sarwaruddin , Begum Bilkis , Rashid Mohammad A
Published: April 2008

Dhaka Univ. J. Pharm. Sci. 6(2): 131-133, 2007 (December)
Fish Parasitological Studies in Bangladesh: A Review
Authors: Chandra KJ
Published: April 2008

Fish parasitological investigation and research performed in Bangladesh has been reviewed through study of available literature. Considerable works mainly on systematics, nature of infestation and pathology of different groups of fish parasites- protozoa, helminths and crustacea have been done. A total of 290 species of parasites have so far been recorded from freshwater and marine fishes in Bangladesh. Ectoparasitic protozoans and monogenetic trematodes are recorded mainly from cultured fish species of farms. Two helminth parasites of zoonotic importance Dibothriocephalus latus and Gnathostoma spinigerum are also reported from Bangladesh fishes. Much attention has been given on caryophyllid cestodes of two catfishes Magur and Singhi. Few fish diseases of parasitic origin have been reported and studied. Commonly occurring parasitic diseases are agrulosis (fish louse), ichthyophthiriasis (white spot) and myxoboliasis. Only few attempts were taken to their control measures using simple chemicals like salt, lime, formalin, dipterex and sumithion. Recommendation has been made for the future works on parasitology for sustainable production of healthy fish.

Key words: Fish parasites, freshwater fishes, marine fishes.
Land Degradation Situation in Bangladesh and Role of Agroforestry
Authors: Hasan MK , Alam AKM Ashraful
Published: April 2008

Degradation of land is a vital issue throughout the world with the particular references to Bangladesh as it a threat to agricultural productivity. Agroforestry, a land use system is being popular in many countries to protect the land from various types of degradation. Studies have proved that agroforestry can check soil erosion to some extent, increase soil fertility, reduce salinity, alkalinity, acidity and desertification etc. ultimately improve soil health which keep the land suitable for agricultural production. The article has drawn on the basis of various reviews focusing the land degradation situation of Bangladesh and potentialities of agroforsetry.

Key words: Land degradation, desertification, agroforestry.
Art and Techniques for Oral Presentation in Distance Education
Authors: Rashid AQM Bazlur
Published: April 2008

Human being is only the unique verbal monster in the nature having worldwide communicative power capable of conveying his thought or deliberation and/ or message/information outside his head to others through different ways among which the vocabulary speech is significantly more important and effective. The instructional approach through multi-mediated method of distance education requires persuasible and emanating resourceful speaker with vocabulary and other necessary art and techniques. Relevant qualifications of the speaker along with some important points of consideration such as determination to succeed, control over nervousness, contemporary knowledge, vocabulary efficiency, choice of words and other techniques for opening presenting and closing a speech etc. have been described. Various art and manner including smiling face with emanating attitude, language and style etc. along with avoidable distracting habits of the presenter have also been elucidated in detail.

Key words: Art and technique, oral presentation, distance education.
Tillering Dynamics and Productivity of BRRI dhan44 as Influenced by Spacing and Nitrogen Management Technique
Authors: Rashid Md. Harunur , Khan Md. Akhter Hossain
Published: April 2008

The experiment was conducted at the Bangladesh Rice Research Institute farm to study the tillering dynamics and the productivity of the variety, BRRI dhan44 under four spacing (20 cm× 15 cm, 25 cm× 15 cm, 20 cm× 20 cm and 25 cm× 25 cm) and varying levels (0, 60, 80, 100 kg N ha-1) and technique (Leaf Color Chart based N) of N. The wider spacing produced higher number of tillers at maximum tillering stage which was not realized in to number of on ear bearing tiller m-2. Grain yield was not influenced by spacing. A similar grain yield of BRRI dhan44 at a wider spacing of 25 cm× 25 cm indicated its suitability where wider spacing is practiced. The higher amount of added N produced higher non bearing tillers hill-1. Grain yield obtained from 80, 100 kg N ha-1 and leaf color chart (LCCN) was comparable.

Key words: Spacing, nitrogen management, tillering dynamics, productivity, rice.
Effect of Relative Humidity on the Development of Head Blight by Bipolaris sorokiniana in Wheat
Authors: Uddin Sheikh Afsar , Khalequzzaman KM , Rashid AQM Bazlur
Published: April 2008

Effect of exposure to different duration of high humidity (5,10,15,20,25 & 30 days) on the development of head blight caused by Bipolaris sorokiniana in wheat was studied in vitro. Maximum leaf blight severity of 42.97% and head blight development of 87.53% caused by the pathogen were recorded for the infected plants incubated for a period of 30 days under condition of high humidity. The treatments did not differ significantly with respect to head blight development except the control. Variable effects of the treatments was observed on the grain quality. The highest diseased (black pointed and shriveled) grains of 62.27% were recorded in treatment 6 (30 days exposure) followed by treatment 5 (25 days exposure) with 48.01% diseased grains. There were no significant differences among the other treatments except the check.

Key words: Humidity, head blight, leaf blight, Bipolaris sorokiniana, wheat.