oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 15 )

2019 ( 913 )

2018 ( 1091 )

2017 ( 1115 )

Custom range...

Search Results: 1 - 10 of 630340 matches for " Alistair M. S. Smith "
All listed articles are free for downloading (OA Articles)
Page 1 /630340
Display every page Item
Discrete Return Lidar in Natural Resources: Recommendations for Project Planning, Data Processing, and Deliverables
Jeffrey S. Evans,Andrew T. Hudak,Russ Faux,Alistair M. S. Smith
Remote Sensing , 2009, DOI: 10.3390/rs1040776
Abstract: Recent years have seen the progression of light detection and ranging (lidar) from the realm of research to operational use in natural resource management. Numerous government agencies, private industries, and public/private stakeholder consortiums are planning or have recently acquired large-scale acquisitions, and a national U.S. lidar acquisition is likely before 2020. Before it is feasible for land managers to integrate lidar into decision making, resource assessment, or monitoring across the gambit of natural resource applications, consistent standards in project planning, data processing, and user-driven products are required. This paper introduces principal lidar acquisition parameters, and makes recommendations for project planning, processing, and product standards to better serve natural resource managers across multiple disciplines.
A Comparison of Two Open Source LiDAR Surface Classification Algorithms
Wade T. Tinkham,Hongyu Huang,Alistair M. S. Smith,Rupesh Shrestha,Michael J. Falkowski,Andrew T. Hudak,Timothy E. Link,Nancy F. Glenn,Danny G Marks
Remote Sensing , 2011, DOI: 10.3390/rs3030638
Abstract: With the progression of LiDAR (Light Detection and Ranging) towards a mainstream resource management tool, it has become necessary to understand how best to process and analyze the data. While most ground surface identification algorithms remain proprietary and have high purchase costs; a few are openly available, free to use, and are supported by published results. Two of the latter are the multiscale curvature classification and the Boise Center Aerospace Laboratory LiDAR (BCAL) algorithms. This study investigated the accuracy of these two algorithms (and a combination of the two) to create a digital terrain model from a raw LiDAR point cloud in a semi-arid landscape. Accuracy of each algorithm was assessed via comparison with >7,000 high precision survey points stratified across six different cover types. The overall performance of both algorithms differed by only 2%; however, within specific cover types significant differences were observed in accuracy. The results highlight the accuracy of both algorithms across a variety of vegetation types, and ultimately suggest specific scenarios where one approach may outperform the other. Each algorithm produced similar results except in the ceanothus and conifer cover types where BCAL produced lower errors.
Sequence and functional analyses of Haemophilus spp. genomic islands
Mario Juhas, Peter M Power, Rosalind M Harding, David JP Ferguson, Ioanna D Dimopoulou, Abdel RE Elamin, Zaini Mohd-Zain, Derek W Hood, Richard Adegbola, Alice Erwin, Arnold Smith, Robert S Munson, Alistair Harrison, Lucielle Mansfield, Stephen Bentley, Derrick W Crook
Genome Biology , 2007, DOI: 10.1186/gb-2007-8-11-r237
Abstract: These genomic islands have core and accessory genes in approximately equal proportion, with none demonstrating recent acquisition from other islands. The number of variable sites within core genes is similar to that found in the host bacteria. Furthermore, the GC content of the core genes is similar to that of the host bacteria (38% to 40%). Most of the core gene content is formed by the syntenic type IV secretion system dependent conjugative module and replicative module. GC content and lack of variable sites indicate that the antibiotic resistance genes were acquired relatively recently. An analysis of conjugation efficiency and antibiotic susceptibility demonstrates that phenotypic expression of genomic island-borne genes differs between different hosts.Genomic islands of the ICEHin1056 subfamily have a longstanding relationship with H. influenzae and H. parainfluenzae and are co-evolving as semi-autonomous genomes within the 'supragenomes' of their host species. They have promoted bacterial diversity and adaptation through becoming efficient vectors of antibiotic resistance by the recent acquisition of antibiotic resistance transposons.Horizontal gene transfer contributes to the diversification and adaptation of micro-organisms. Apart from the core genes that are present in all strains of the same species and are the minimum necessary for survival under optimal growth conditions, bacterial genomes also harbor a variable number of accessory genes that are acquired by horizontal gene transfer, many of which are crucial for bacterial adaptation and survival. The sum of the core genes and accessory genes across the species represent what is regarded as the 'supragenome'. The accessory genes are frequently aggregated into heterogeneous sets of hitherto ill-defined structures called genomic islands, the origins of which are unknown. We recently reported on a set of genomic islands found among Proteobacteria that shared a common ancestor and were coherently structured
Optical Light Curves of the Type Ia Supernovae 1990N and 1991T
P. Lira,Nicholas B. Suntzeff,M. M. Phillips,Mario Hamuy,Jose Maza,R. A. Schommer,R. C. Smith,Lisa A. Wells,R. Aviles,J. A. Baldwin,J. H. Elias,L. Gonzalez,A. Layden,M. Navarrete,P. Ugarte,Alistair R. Walker,Gerard M. Williger,F. K. Baganoff,Arlin P. S. Crotts,R. Michael Rich,N. D. Tyson,A. Dey,P. Guhathakurta,J. Hibbard,Y. -C. Kim,Daniel M. Rehner,E. Siciliano,Joshua Roth,Patrick Seitzer,T. B. Williams
Physics , 1997, DOI: 10.1086/300175
Abstract: We present UBVRI light curves for the bright Type Ia supernovae SN 1990N in NGC 4639 and SN 1991T in NGC 4527 based on photometry gathered in the course of the Calan/Tololo supernova program. Both objects have well-sampled light curves starting several days before maximum light and spanning well through the exponential tail. These data supercede the preliminary photometry published by Leibundgut et al (1991) and Phillips et al (1992). The host galaxies for these supernovae have (or will have) accurate distances based on the Cepheid period-luminosity relationship. The photometric data in this paper provide template curves for the study of general population of Type Ia supernova and accurate photometric indices needed for the Cepheid-supernova distance scale.
The properties of XO-5b and WASP-82b redetermined using new high-precision transit photometry and global data analyses
A. M. S. Smith
Physics , 2014,
Abstract: This paper presents new transit photometry from the Isaac Newton Telescope of two transiting exoplanetary systems, XO-5 and WASP-82. In each case the new transit light curve is more precise than any other of that system previously published. The new data are analysed alongside previously-published photometry and radial velocities, resulting in an improved orbital ephemeris and a refined set of system parameters in each case. The observational baseline of XO-5 is extended by very nearly four years, resulting in a determination of the orbital period of XO-5b to a precision of just 50 ms. The mass and radius of XO-5b are 1.19$\pm$0.03 and 1.14$\pm$0.03 times those of Jupiter, respectively. The light curve of WASP-82 is only the second published for this system. The planetary mass is 1.25$\pm$0.05 $M_{\rm Jup}$, and the radius is 1.71$\pm$0.08 $M_{\rm Jup}$.
Feasibility and acceptability of wrist actigraph in assessing sleep quality and sleep quantity: A home-based pilot study in healthy volunteers  [PDF]
Zaswiza Mohamad Noor, Alesha J. Smith, Simon S. Smith, Lisa M. Nissen
Health (Health) , 2013, DOI: 10.4236/health.2013.58A2010
Abstract:

Purpose: This study aimed to determine the feasibility and acceptability of actigraphy to monitor sleep quality and quantity in healthy self-rated good sleeper adults at home-based settings. Method: Sixteen healthy volunteers (age > 18) were invited to participate. Each participant was provided with a wrist actigraph device to be worn for 24-hour/day for seven consecutive days to monitor their sleep-wake patterns. Actigraphy data were downloaded using-proprietary software to generate an individual-sleep report. Participants also completed a set of self-reported Health Related Quality of Life (HRQOL) using WHO (five) Well Being Index (WBI) questionnaires. Results: Actigraphy was well accepted by all participants. Only 43.8% of the participants achieved normal total sleep time (TST) and 62.5% had a mean sleep efficiency value below the normal range. Despite a reduced quality of sleep among the participants, the self-reported HRQOL scores produced by the WHO-5 WBI showed a “fair” to “good” among the participants. Conclusions: To maintain healthy well-being, it is vital to have efficient and quality sleep. Insufficient and poor sleep may contribute to various health problems and hazardous outcomes. People often believe they have normal and efficient sleep, not realising they may be developing poor sleep habits. This study found that actigraphy can be easily utilized to monitor sleep-wake patterns at home-based settings. We proposed that actigraphy could be adapted for use in the primary care settings (e.g. community pharmacy) to improve the sleep health management in the community.

La escuela publica en Mexico y la definición incierta de la nación
Castro, Inés;Smith, Márcia;
Cadernos CEDES , 2011, DOI: 10.1590/S0101-32622011000100004
Abstract: in mexico, schools have always been part of the discourse on integration, homogenization and the construction of national identity. the main interest was to ensure continuity to the western european culture, filtered through the hispanic singularity and penetrated by the idealized recognition of the autochthonous (indigenous peoples). however, the growth of poverty and the permanent historical tendency to ethnic discrimination, as opposed to the widening discourse on human rights, have invalidated the achievement of the original school's goals. in the last decade, strong ideas of multiculturalism have arisen, which wish to integrate and renew school's propositions. these ideas derive from the increasing recognition of the expanding cultural diversity and of the shortcomings of the cultural mestizaje project implemented in the country in previous times, which advocated an almost "forced" cultural integration that was impossible.
The prevalence of post-abortion syndrome in patients presenting at Kalafong Hospital's Family Medicine Clinic after having a termination of pregnancy
M Van Rooyen, S Smith
South African Family Practice , 2004,
Abstract: Background: Post-abortion syndrome (PAS) is said to be the emotional, psychological, physical and spiritual trauma caused by an abortion, which is an event outside the normal range of human experience. Post-abortion syndrome is a type of post-traumatic disorder and is characterised by a stressor (the abortion), the event being re-experienced, avoidance and/or numbing of general responsiveness, and physical symptoms such as insomnia and depression. The question was asked whether the patients at Kalafong Hospital experienced any of the after-effects of a termination of pregnancy and whether these effects would fulfill the criteria of post-abortion syndrome. Method: A prospective descriptive study was done over a six-month period. All female patients presenting at the Family Medicine Clinic of Kalafong Hospital who were known to have had a previous abortion on request were asked to participate in the study. After obtaining informed consent, a structured questionnaire on their psychological symptoms was completed by the participants with the help of the researcher. The questionnaire contained demographic data, as well as questions on the above-mentioned symptoms of PAS. To fulfill the criteria of PAS, the symptoms should have been present for more than a month and must have affected the subject's daily functioning. Results: Of the 48 woman recruited, 16 (33%) fulfilled the criteria of PAS, and more than 50% of the women had had some or other emotional or psychological after-effect. Conclusion: This study showed that one out of every three women presenting at Kalafong Hospital after abortion fulfilled the criteria of PAS. Since family physicians are committed to their patients and regard it as their duty to address problems prevalent in the community they serve, it is necessary to investigate further the possible link between termination of pregnancy and the emotional problems identified. It is imperative that women requesting termination of pregnancy receive comprehensive counseling prior to the procedure, as well as support thereafter, to ensure that they are not unnecessarily traumatised. For full text click here:SA Family Pract 2004;46(5): 21-24
On the importance of cumulus penetration on the microphysical and optical properties of stratocumulus clouds
S. Ghosh, S. Osborne,M. H. Smith
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2005,
Abstract: Owing to their extensive spatial coverage, stratocumulus clouds play a crucial role in the radiation budget of the earth. Climate models need an accurate characterisation of stratocumulus in order to provide an accurate forecast. However, remote sensing as well as in-situ observations reveal that on several occasions, cumulus clouds present below the stratocumulus, often have a significant impact on the main stratocumulus microphysical properties. This was observed during the ACE-2 (Aerosol Characterisation Experiment-2) campaign designed to study the impact of polluted continental air on stratocumulus formation. In this paper we used a detailed micro-physical chemical parcel model to quantify the extent of this cumulus-stratocumuls coupling. In addition, we made extensive use of microphysical observations from the C-130 aircraft that was operated during ACE-2. For the ACE-2 case studies considered in this paper, our analysis revealed that the chemical, microphysical and optical characteristics of the main stratocumulus cloud deck had significant contributions from cumulus clouds that often penetrated the stratocumulus deck. The amount of fine mode ionic species, the average droplet number concentrations, the effective radii and the optical depths during the flight A562 (when cumulus clouds interacted with the main stratocumulus) were estimated and model runs that included this effect yielded microphysical and optical properties which compared more favourably with the observations than the runs which did not. This study highlights the importance of including these cumulus effects in stratocumulus related modelling studies.
On the importance of cumulus penetration on the microphysical and optical properties of stratocumulus clouds
S. Ghosh,S. Osborne,M. H. Smith
Atmospheric Chemistry and Physics Discussions , 2004,
Abstract: Owing to their extensive spatial coverage, stratocumulus clouds play a crucial role in the radiation budget of the earth. Climate models need an accurate characterisation of stratocumulus in order to provide an accurate forecast. However, remote sensing as well as in-situ observations reveal that on several occasions, cumulus clouds present below the stratocumulus, often have a significant impact on the main stratocumulus microphysical properties. This was observed during the ACE-2 (Aerosol Characterisation Experiment 2) campaign designed to study the impact of polluted continental air on stratocumulus formation. In this paper we used a detailed micro-physical chemical parcel model to quantify the extent of this cumulus-stratocumuls coupling. In addition, we made extensive use of microphysical observations from the C-130 aircraft that was operated during ACE-2. For the ACE-2 case studies considered in this paper, our analysis revealed that the chemical, microphysical and optical characteristics of the main stratocumulus cloud deck had significant contributions from cumulus clouds that often penetrated the stratocumulus deck. The amount of fine mode ionic species, the average droplet number concentrations, the effective radii and the optical depths during the flight A562 (when cumulus clouds interacted with the main stratocumulus) were estimated and model runs that included this effect yielded microphysical and optical properties which compared more favourably with the observations than the runs which did not. This study highlights the importance of including these cumulus effects in stratocumulus related modelling studies.
Page 1 /630340
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.