The blood groups of the Natal Indian people.

Thesis (Ph.D.)-University of Natal, Durban, 1980.No abstract available

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Micropatterning Proteins and Synthetic Peptides on Solid Supports: A Novel Application for Microelectronics Fabrication Technology

In this paper, we describe a method for immobilizing proteins and synthesizing peptides in micrometer-dimension patterns on solid supports. Microelectronics fabrication technology was adapted and used to lithographically direct the location of immobilization of proteins on appropriately derivatized surfaces. As examples, we micropatterned the protein bovine serum albumin (BSA) and the enzyme horseradish peroxidase (HRP). The catalytic activity of HRP was shown to be retained after being cross-linked to the support. When coupled with solid-phase peptide synthesis, the technique allowed synthetic peptides to be constructed in patterns again having micrometer dimensions. Synthetic polypeptides, polylysine, were constructed in patterns with dimensions that approached the practical limit of resolution for optical lithography at 1-2 μman. The patterns of immobilized molecules and synthetic peptides were visualized using histochemical methods together with light and fluorescence microscopy. The protein and peptide patterning technique described here is an advance in the field of bioelectronics. In particular, it should now be possible to devise novel methods for interfacing with biological systems and constructing new devices for incorporation into miniaturized biosensors

Slow Degradation Of Atp In Simulated Martian Environments Suggests Long Residence Times For The Biosignature Molecule On Spacecraft Surfaces On Mars

Prelaunch planetary protection protocols on spacecraft are designed to reduce the numbers and diversity of viable bioloads on surfaces in order to mitigate the forward contamination of planetary surfaces. In addition, there is a growing appreciation that prelaunch spacecraft cleaning protocols will be required to reduce the levels of biogenic signature molecules on spacecraft to levels that will not compromise life-detection experiments on landers. The biogenic molecule, adenosine triphosphate (ATP) was tested for long-term stability under simulated Mars surface conditions of high UV flux, low temperature, low pressure, Mars atmosphere, and clear-sky dust loading conditions. Data on UV-induced ATP degradation rates were then extrapolated to a diversity of global conditions using a radiative transfer model for UV on Mars. The UV-induced degradation of ATP tested at 4.1 W m-2 UVC (200-280 nm), -10 °C, 7.1 mb, 95% CO2 gas composition, and an atmospheric opacity of τ = 0.1 yielded a half-life for ATP of 1342 kJ m-2; or extrapolated to approximately 22 sols on equatorial Mars with an atmospheric opacity of τ = 0.5. Temperature was found to moderately affect ATP degradation rates under martian conditions; tests at -80 or 20 °C yielded ATP half-lives of 2594 or 1183 kJ m-2, respectively. The ATP degradation rates reported here are over 10 orders of magnitude slower than the UV-induced biocidal rates reported in the literature on the inactivation of strongly UV-resistant bacterial spores from Bacillus pumilus SAFR-032 [Schuerger, A.C., Richards, J.T., Newcombe, D.A., Venkateswaran, K.J., 2006. Icarus 181, 52-62]. Extrapolating results to global Mars conditions, residence times for a 99% reduction of ATP on spacecraft surfaces ranged from 158 sols on Sun-exposed surfaces to approximately 32,000 sols for the undersides of landers similar to Viking. However, spacecraft materials greatly affected the survival times of ATP under martian conditions. Stainless steel was found to enhance the UV degradation of ATP by over 2 orders of magnitude compared to ATP-doped iridited aluminum, graphite, and astroquartz coupons. Extrapolating these results to global conditions, ATP on stainless steel might be expected to persist between 2 and 320 sols for upper and lower surfaces of landers. Liquid chromatography-mass spectrometry data supported the conclusion that UV irradiation acted to remove the γ-phosphate group from ATP, and no evidence was observed for the UV-degradation of d-ribose or adenine moieties. Long residence times for ATP on spacecraft materials under martian conditions suggest that prelaunch cleaning protocols may need to be strengthened to mitigate against possible ATP contamination of life-detection experiments on Mars landers. © 2007 Elsevier Inc. All rights reserved

Slow degradation of ATP in simulated martian environments suggests long residence times for the biosignature molecule on spacecraft surfaces. Icarus 194:86–100

Abstract Prelaunch planetary protection protocols on spacecraft are designed to reduce the numbers and diversity of viable bioloads on surfaces in order to mitigate the forward contamination of planetary surfaces. In addition, there is a growing appreciation that prelaunch spacecraft cleaning protocols will be required to reduce the levels of biogenic signature molecules on spacecraft to levels that will not compromise life-detection experiments on landers. The biogenic molecule, adenosine triphosphate (ATP) was tested for long-term stability under simulated Mars surface conditions of high UV flux, low temperature, low pressure, Mars atmosphere, and clear-sky dust loading conditions. Data on UV-induced ATP degradation rates were then extrapolated to a diversity of global conditions using a radiative transfer model for UV on Mars. The UV-induced degradation of ATP tested at 4.1 W m −2 UVC (200-280 nm), −10 • C, 7.1 mb, 95% CO 2 gas composition, and an atmospheric opacity of τ = 0.1 yielded a half-life for ATP of 1342 kJ m −2 ; or extrapolated to approximately 22 sols on equatorial Mars with an atmospheric opacity of τ = 0.5. Temperature was found to moderately affect ATP degradation rates under martian conditions; tests at −80 or 20 • C yielded ATP half-lives of 2594 or 1183 kJ m −2 , respectively. The ATP degradation rates reported here are over 10 orders of magnitude slower than the UV-induced biocidal rates reported in the literature on the inactivation of strongly UV-resistant bacterial spores from Bacillus pumilus SAFR-032 [Schuerger, A.C., Richards, J.T., Newcombe, D.A., Venkateswaran, K.J., 2006. Icarus 181, 52-62]. Extrapolating results to global Mars conditions, residence times for a 99% reduction of ATP on spacecraft surfaces ranged from 158 sols on Sun-exposed surfaces to approximately 32,000 sols for the undersides of landers similar to Viking. However, spacecraft materials greatly affected the survival times of ATP under martian conditions. Stainless steel was found to enhance the UV degradation of ATP by over 2 orders of magnitude compared to ATP-doped iridited aluminum, graphite, and astroquartz coupons. Extrapolating these results to global conditions, ATP on stainless steel might be expected to persist between 2 and 320 sols for upper and lower surfaces of landers. Liquid chromatography-mass spectrometry data supported the conclusion that UV irradiation acted to remove the γ -phosphate group from ATP, and no evidence was observed for the UV-degradation of D-ribose or adenine moieties. Long residence times for ATP on spacecraft materials under martian conditions suggest that prelaunch cleaning protocols may need to be strengthened to mitigate against possible ATP contamination of life-detection experiments on Mars landers

International priorities for research in nursing informatics for patient care

The Nursing Informatics International Research Network (NIIRN) is a group of experts who are collaborating on the development of internationally relevant research programs for nursing informatics. In this paper we outline key findings of a survey exploring international research priorities for nursing informatics. The survey was available online during May-August 2012. Respondents were asked to rate each of 20 listed research topics in terms of respondent's views of its priority for nursing informatics research. 468 completed surveys were received representing respondents from six World Health Organization regions. The two most highly ranked areas of importance for research were development of systems to provide real time feedback to nurses and assessment of the impact of HIT on nursing care and patient outcomes. The lowest ranked research topics were theory development and integrating genomic data into clinical information systems. The identification of these priorities provides a basis for future international collaborative research in the field of nursing informatics.5 page(s