1,232 research outputs found
Towards a metric for open source software quality
Software quality is more than just conformance to a set of requirements and represents many attributes related to each other that make up a piece of software. An important part of this measure depends on the underlying processes and methodologies used in the engineering of software. We present an early exposition towards a quality model for open source software (OSS). We describe some basic notions of quality for OSS and present a basic model, where quality notions consist of various factors that influence such quality. The purpose of this effort is ultimately to develop a quantitative metric for software quality
Synthesis, Characterization and Antimicrobial Studies of Schiff Base Derived from the Reaction of 2-Thiophenecarboxaldehyde and Ethylenediamine and its Metal (II) Complexes
Schiff base was derived by condensation of 2-thiophenecarboxaldehyde and ethylenediamine. Its Mn(II), Fe(II) and Co(II) complexes have been prepared and characterized on the basis of melting point/decomposition temperature, solubility, molar conductance, magnetic susceptibility, elemental analysis, infrared spectroscopic analysis and UV-visible spectrophotometry. The Schiff base and complexes were found to be soluble in DMSO, DMF and some organic solvents thus, they are non-ionic compounds. The Decomposition temperatures of the complexes were found to be within the range of 173-246°C, showing the stability of the complexes. All the complexes have low molar conductance values (8.66-25.29 Ω−1 cm2 mol−1) indicating their non- electrolytic nature. Magnetic moment values of the complexes were found to be within the range of 3.847BM - 5.12BM which indicated that they are paramagnetic. Infrared spectra of the Schiff base indicated the azomethine peak at 1629cm-1 which shifted to the lower frequencies (1603-1562cm-1) in the spectra of the complexes. Both analytical and spectroscopic data showed that the complexes were formed and the coordination sites were through the nitrogen of the azomethine (-HC=N-) group and the sulfur atom of the thiophene ring. 1:1 metal-ligand ratio was suggested The Schiff base and its complexes have been screened for their in vitro antimicrobial activity against three pathogenic bacteria (Staphylococcus aureus, Streptococcus pneumonia and Escherichia coli) and two pathogenic fungi (Aspergillus niger and Aspergillus flavus). The Schiff base shows moderate inhibition zone (06 - 14) whereas some of the metal chelates show slightly higher inhibition zone (06 - 17) mm against the bacteria and fungi but lower than that of the control drugs used (18-30) mm
Performing against the odds: developmental trajectories of children in the EPPSE 3 to 16 study
The Effective Pre-School, Primary and Secondary Education (EPPSE 3 to 16) research project is a large scale, longitudinal, mixed-methods research that is following the progress of 3,000 children since 1997 from the age of 3- to 16-years-old.
A focus for EPPSE has been the extent to which pre-school, compulsory education and children’s home learning experiences (HLE) can reduce inequality. Earlier EPPSE found that what parents did with their children was important in terms of the children’s outcomes, not simply ‘who they were’ in terms of social class and income.
Following a pilot study with disadvantaged children who were ‘succeeding against the odds’ towards the end of primary school, this study provides in-depth exploration and explanation of how risks and protective factors in the lives of children shape their learning life-courses, and why they lead to academic resilience for some but not for others
EFFECTIVE SCHOOL MODEL; MALAYSIAN PERSPECTIVE
The excellence education has become the primary concern for achievement to compete in this global village. Since the technological and vocational higher education became one of the essential elements in the educational road map, students are expected to be more skillful than the one of regular university. This stutfy reviews the development of effective learning systems and examines the relationship between employability and effective learning systems from students' perception. The results found that the model indicates a highly acceptable fit between the model and data. Also, there exists significant direct effect between employability and effective learning systems.
Key words: school model, malaysian
GC-MS Analysis of Insecticidal Leaf Essential Oil of Pyrenacantha Staudtii Hutch and Dalz (Icacinaceae)
Purpose: Insecticides have been known to cause serious toxicological and environmental problems. Hence, the insecticidal activity and chemical composition of a local medicinal plant was investigated.Methods: Steam distillation of P.staudtii leaves was carried out using a Clavenger apparatus in order to obtain the volatile oils. Gas chromatography/mass spectrometric (GC/MS) analyses (DB-5 Optima-5 column) of the essential oil were performed and its insecticidalactivity determined.Results: GC-MS spectrometry showed that the major chemical components of the oil were tetradecanoic acid (22 %), hexanoic acid, α-phellandrene (13 %), and citronellol sp. (7 %). The work also revealed significant insecticidal activity of 80 % and 60 % against Rhyzoperthadominica and Tribolium castaneum, respectively.Conclusion: The study established the chemical composition and insecticidal activity of the essential oil of the plant leaf. Future formulation studies, toxicity profile and possible mechanism of action may lead to the development of a potential insecticidal product
Glyoxalase I expression pattern in Hevea brasiliensis seedlings under varied stress conditions
Drought is one of the most important stress factors which adversely affect plants’ growth and productivity. Global climate change may make this situation more serious in the years ahead. Considering the long time span required for the generation of drought resistant genotypes in Rubber (Hevea brasiliensis) through conventional breeding, molecular interventions to engineer plants to have either drought responsive genes or genes expected to alter osmotic regulation would be very attractive. The glyoxalase pathway involving glyoxalase I and glyoxalase II enzymes is required for glutathionebased detoxification of methylglyoxal. In this study the effects of various abiotic stresses on the upregulation of methylglyoxal levels and glyoxalase I activities in Hevea brasiliensis seedlings were investigated. Most of the stresses caused significant increase in methylglyoxal level and glyoxalase I activity, among which drought caused the highest induction of glx I followed by salinity, 2, 4-D, ABA, methylglyoxal, white light and CdCl2. The stress-induced increases in methylglyoxal and glyoxalase I activity found in the present study suggest an important role of glyoxalase I in conferring drought tolerance. The up-regulation of glyoxalase I under drought stress indicates its future utility in developing tolerance to drought stress in Hevea brasiliensis. In the present study, a partial cDNA sequence coding for glyoxalase I was amplified by PCR using specific primers. The 440 bp cDNA amplicon obtained was sequenced and subjected to online BLAST analysis. The sequence of Hevea brasiliensis glyoxalase I (GenBank Acc. No: GU598520) had six open reading frames. The ORF finder revealed the longest ORF of 336 bp. Glyoxalase I from Ricinus communis had the highest nucleotide sequence homology (90%) compared to the amplified gene. BLASTP analysis also showed high homology between the deduced protein sequence of the amplified gene and glyoxalases from other species. Our results suggest that the multi-stress inducibility of glyoxalase I in the present study may be due to the fact that it might protect the plants against MG that is formed under various stresses including drought and confers tolerance by increasing the GSH-based detoxification system and decreasing lipid peroxidationKeywords: Glyoxalase I, Hevea brasiliensis, Methylglyoxal, drought tolerance, abiotic stres
Methodologies and tools for OSS: current state of the practice
Over the years, the Open Source Software (OSS) development has matured and strengthened, building on some established methodologies and tools. An understanding of the current state of the practice, however, is still lacking. This paper presents the results of a survey of the OSS developer community with a view to gain insight of peer review, testing and release management practices, along with the current tool sets used for testing, debugging and, build and release management. Such an insight is important to appreciate the obstacles to overcome to introduce certification and more rigour into the development process. It is hoped that the results of this survey will initiate a useful discussion and allow the community to identify further process improvement opportunities for producing better quality software
Specifying authentication using signal events in CSP
The formal analysis of cryptographic protocols has developed into a comprehensive body of knowledge, building on a wide variety of formalisms and treating a diverse range of security properties, foremost of which is authentication. The formal specification of authentication has long been a subject of examination. In this paper, we discuss the use of correspondence to formally specify authentication and focus on Schneider's use of signal events in the process algebra Communicating Sequential Processes (CSP) to specify authentication. The purpose of this effort is to strengthen this formalism further. We develop a formal structure for these events and use them to specify a general authentication property. We then develop specifications for recentness and injectivity as sub-properties, and use them to refine authentication further. Finally, we use signal events to specify a range of authentication definitions and protocol examples to clarify their use and make explicit related theoretical issues. our work is motivated by the desire to effectively analyse and express security properties in formal terms, so as to make them precise and clear. (C) 2008 Elsevier Ltd. All rights reserved
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