383 research outputs found
Evolutionary Computation
This book presents several recent advances on Evolutionary Computation, specially evolution-based optimization methods and hybrid algorithms for several applications, from optimization and learning to pattern recognition and bioinformatics. This book also presents new algorithms based on several analogies and metafores, where one of them is based on philosophy, specifically on the philosophy of praxis and dialectics. In this book it is also presented interesting applications on bioinformatics, specially the use of particle swarms to discover gene expression patterns in DNA microarrays. Therefore, this book features representative work on the field of evolutionary computation and applied sciences. The intended audience is graduate, undergraduate, researchers, and anyone who wishes to become familiar with the latest research work on this field
Aerospace medicine and biology: A continuing bibliography with indexes (supplement 349)
This bibliography lists 149 reports, articles and other documents introduced into the NASA Scientific and Technical Information System during April, 1991. Subject coverage includes: aerospace medicine and psychology, life support systems and controlled environments, safety equipment, exobiology and extraterrestrial life, and flight crew behavior and performance
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Enhanced structure determination from powder diffraction data via algorithm optimisation and the use of conformational information
The performance of DASH has been evaluated against powder X-ray diffraction data collected
from 101 molecular crystal structures, representing the most comprehensive testing of a
"structure determination from powder diffraction data" (SDPD) program carried out to date.
These 101 structures cover a broad range of molecular complexities, from very simple (6
degrees of freedom) to very challenging (49 degrees of freedom). 95 of the crystal structures
could be solved with the current version of DASH, going some way to explaining why the
parameterisation of its simulated annealing (SA) algorithm has not been altered since the
launch of the program in 1999.
This thesis explores optimisation of key DASH SA parameters using the program irace. The
irace runs, comprising 255,000 individual DASH runs and requiring approximately 1300 CPU
days of compute time, produced six sets of SA parameters which differed greatly from the
DASH default parameters and which markedly improved the performance of DASH. Further
evaluation of these six sets against all 101 compounds (a further 2874 of days of CPU time),
allowed selection of one best-performing set, which delivered an order of magnitude
improvement in the success rate with which crystal structures were solved. The adoption of
these parameter values as the defaults in future releases of DASH is strongly recommended
and is expected to broaden the range of molecular complexities to which the program can be
applied.
Three distinct approaches to further improving DASH performance, based on introducing prior
conformational knowledge derived from the Cambridge Structural Database (CSD), have also
been assesed. The findings show that inclusion of conformational knowledge brings significant
additional gains in SDPD performance, and that existing implementations of these approaches
in the DASH / CSD System are close to being ready for routine use
The doctoral research abstracts. Vol:6 2014 / Institute of Graduate Studies, UiTM
Congratulations to Institute of Graduate
Studies on the continuous efforts to publish the 6th
issue of the Doctoral Research Abstracts which ranged
from the discipline of science and technology,
business and administration to social science and
humanities.
This issue captures the novelty of research from 52
PhD doctorates receiving their scrolls in the UiTMās
81st Convocation. This convocation is very significant
especially for UiTM since we are celebrating the
success of 52 PhD graduands ā the highest number
ever conferred at any one time.
To the 52 doctorates, I would like it to be known
that you have most certainly done UiTM proud by
journeying through the scholastic path with its endless
challenges and impediments, and by persevering
right till the very end.
This convocation should not be regarded as the end of
your highest scholarly achievement and contribution
to the body of knowledge but rather as the beginning
of embarking into more innovative research from
knowledge gained during this academic journey, for
the community and country.
As alumni of UiTM, we hold
you dear to our hearts. The
relationship that was once
between a student and
supervisor has now matured
into comrades, forging
and exploring together
beyond the frontier of
knowledge. We wish
you all the best in
your endeavour
and may I offer my
congratulations to
all the graduands.
āUiTM sentiasa dihati
kuā
Tan Sri Datoā Sri Prof Ir Dr Sahol Hamid Abu Bakar ,
FASc, PEng
Vice Chancellor
Universiti Teknologi MAR
Eleventh European Powder Diffraction Conference. Warsaw, September 19-22, 2008
Zeitschrift fĆ¼r Kristallographie. Supplement Volume 30 presents the complete Proceedings of all contributions to the XI European Powder Diffraction Conference in Warsaw 2008: Method Development and Application,Instrumental, Software Development, Materials. Supplement Series of Zeitschrift fĆ¼r Kristallographie publishes Proceedings and Abstracts of international conferences on the interdisciplinary field of crystallography
Breast Cancer Progression and Phytoestrogen Interactions with Estrogen Receptors
Breast cancer is one of the most common diseases affecting women and approximately 1.3 million females are diagnosed each year with this disease worldwide. Breast cancer is a multi-factorial disease and it is difficult to predict or control the physiopathology, to date one of the major risk factors alongside the patientās genetic background is life time exposure to estrogen. Understanding the estrogen receptor (ER) has been a milestone in elucidating breast cancer biology, leading to advances in disease management. Alongside this, evidence from epidemiological studies suggests that dietary consumption of phytoestrogens may modulate disease progression. This study hypothesises that the interaction between some phytoestrogens (present in the pre-diagnosis diet or in the new diet adopted by breast cancer patients) and specific ER isoforms displayed in breast tumours influences the action of synthetic and endogenous estrogen in breast cancer cells. This study aimed to understand the interaction between estrogen, hormone drugs and phytoestrogens on the ER. In silico modelling of the ER focused on the wild type isoforms ERĪ± and ERĪ² and different ligands (SWISS MODEL and docked through AutoDock Vina). Subsequently, isoforms of ERĪ± and ERĪ² and different ligands (E1, E2, E3, PE, Tamoxifen, ICI 182,780) were modelled and tested by docking against the same set of ligands (E1, E2, E3, PE, Tamoxifen, ICI 182,780).
The system described here highlighted the main amino acid residues of the LBD of ERĪ± and ERĪ² along with ligand interactions for both agonists and antagonists, described in previous X-ray crystallography experiments. All of the phytoestrogens studied using AutoDock Vina interacted with the hormone binding site of both ERĪ± and ERĪ², due the phenolic ring of the studied structure which favoured the interaction with the hydrophobic environment of LBD amino acids. All of the dietary phytoestrogens showed lower binding affinity (<9.1 Kcal/mol) compared with estradiol (-10.6 Kcal/mol) in all the isoforms and isotypes studied, suggesting that phytoestrogens should not displace estradiol from the LBD, however it remains unclear if PE can act as an agonist compound in the ER pathways. Also, some phytoestrogens appeared to have greater affinity to the ERĪ± and ERĪ² than Tamoxifen (antagonist models), but it is uncertain as to whether the resulting structure will interfere with subsequent interactions. Further laboratory experiments will be necessary to understand the impact of the PE in the ERs structure and the respective role in the ER pathway.
The data from this computer modelling approach has provided an insight into the interactions between endogenous estrogens, drugs, phytoestrogens and ER. The in silico studies generated a system that recapitulated data obtained by other research groups (experimentally) and will be of value as a screening tool for further studies of new drugs and exogenous estrogens and their potential role in ER-induced breast cancer pathophysiology
Complexity, Emergent Systems and Complex Biological Systems:\ud Complex Systems Theory and Biodynamics. [Edited book by I.C. Baianu, with listed contributors (2011)]
An overview is presented of System dynamics, the study of the behaviour of complex systems, Dynamical system in mathematics Dynamic programming in computer science and control theory, Complex systems biology, Neurodynamics and Psychodynamics.\u
Functional and structural studies of an Enterococcal Serine/Threonine kinase and its contribution to antibiotic resistance mechanisms
The emergence of vancomycin-resistant enterococci (VRE) since the 1980s has turned this Gram-positive bacterium into a serious and growing clinical challenge. Enterococci have acquired resistance to a number of different antibiotics and are intrinsically resistant to cephalosporin b-lactam drugs. As a result, they are now placed in the World Health Organisation list of priority pathogens for which new antibiotics are urgently needed. An important risk factor for the emergence of VRE is treatment with cephalosporins, suggesting a connection between the origins of resistance between these two different types of antibiotics, the mechanistic basis for which was unknown.
In this study I demonstrate that cephalosporin resistance is significantly enhanced in the well characterized E. faecalis OG1RF strain containing the Tn1549 transposon conferring the VanB type vancomycin resistance. Cephalosporin resistance is shown to be enhanced to the presence of the Tn1549 transposon and a single, chromosomally encoded Serine/Threonine (ST) kinase gene called ireK. Complementation experiments and fluorescence microscopy with a range of biophysical techniques to characterise the protein. Deletion of the gene results in cephalosporin sensitivity. Moreover, this phenotype can be chemically simulated by treatment of E. faecalis with inhibitors of cytoplasmic ST kinases such as staurosporine, demonstrating a requirement for ST kinase activity for cephalosporin resistance. This also demonstrates a therapeutic potential for targeting ST kinases in Gram-positive pathogens with small molecule inhibitors to restore cephalosporin sensitivity which may have clear translational significance. IreK was identified as a key protein involved in enhanced cephalosporin resistance and led to examination of its extracellular and intracellular domains to understand its signal transduction mechanisms and its linkage to resistance. The extracellular domain of IreK was essential for cellular location. Further biophysical experiments identified ligands for the extracellular domains include sugar motifs such as the glycan backbone of peptidoglycans and sugar containing antibiotics. This has led to a new functional model for ST kinases in enterococci
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