The survey for ionization in neutral gas galaxies. I. Description and initial results

We introduce the Survey for Ionization in Neutral Gas Galaxies (SINGG), a census of star formation in H I selected galaxies. The survey consists of H alpha and R-band imaging of a sample of 468 galaxies selected from the H I Parkes All Sky Survey (HIPASS). The sample spans three decades in H I mass and is free of many of the biases that affect other star-forming galaxy samples. We present the criteria for sample selection, list the entire sample, discuss our observational techniques, and describe the data reduction and calibration methods. This paper focuses on 93 SINGG targets whose observations have been fully reduced and analyzed to date. The majority of these show a single emission line galaxy (ELG). We see multiple ELGs in 13 fields, with up to four ELGs in a single field. All of the targets in this sample are detected in H alpha, indicating that dormant (non-star-forming) galaxies with M-H I greater than or similar to 3x10(7) M-circle dot are very rare. A database of the measured global properties of the ELGs is presented. The ELG sample spans 4 orders of magnitude in luminosity (H alpha and R band), and H alpha surface brightness, nearly 3 orders of magnitude in R surface brightness and nearly 2 orders of magnitude in H alpha equivalent width (EW). The surface brightness distribution of our sample is broader than that of the Sloan Digital Sky Survey (SDSS) spectroscopic sample, the EW distribution is broader than prism-selected samples, and the morphologies found include all common types of star-forming galaxies (e.g., irregular, spiral, blue compact dwarf, starbursts, merging and colliding systems, and even residual star formation in S0 and Sa spirals). Thus, SINGG presents a superior census of star formation in the local universe suitable for further studies ranging from the analysis of H II regions to determination of the local cosmic star formation rate density.

Trans-cis Isomerism and acylimine formation in DsRed chromophore models: Intrinsic rotation barriers

The chromophore of the red fluorescent protein DsRed contains an acylimine substituent to a GFP-like chromophore structure. The acylimine is formed from the trans peptide linkage between residues F65 and Q66 in immature DsRed, but has a cis configuration in the mature protein. The relationship between acylimine formation and trans–cis isomerization is unresolved. We have calculated bond rotation profiles for models of mature and immature DsRed chromophores using B3LYP DFT. The isomerization barrier is substantially reduced in acylimine-substituted models, providing prima facie evidence that acylimine formation precedes trans–cis isomerization in DsRed chromophores.

NGC922 - a New Drop-through Ring Galaxy

We have found the peculiar galaxy NGC 922 to be a new drop-through ring galaxy using multiwavelength (ultraviolet-radio) imaging and spectroscopic observations. Its 'C'-shaped morphology and tidal plume indicate a recent strong interaction with its companion which was identified with these observations. Using numerical simulations we demonstrate that the main properties of the system can be generated by a high-speed off-axis drop-through collision of a small galaxy with a larger disc system, thus making NGC 922 one of the nearest known collisional ring galaxies. While these systems are rare in the local Universe, recent deep Hubble Space Telescope images suggest they were more common in the early Universe.

First-principle study of adsorption of hydrogen on Ti-doped Mg(0001) surface

Ab initio density functional theory (DFT) calculations are performed to study the adsorption of H-2 molecules on a Ti-doped Mg(0001) surface. We find that two hydrogen molecules are able to dissociate on top of the Ti atom with very small activation barriers (0.103 and 0.145 eV for the first and second H-2 molecules, respectively). Additionally, a molecular adsorption state of H-2 above the Ti atom is observed for the first time and is attributed to the polarization of the H-2 molecule by the Ti cation. Our results parallel recent findings for H-2 adsorption on Ti-doped carbon nanotubes or fullerenes. They provide new insight into the preliminary stages of hydrogen adsorption onto Ti-incorporated Mg surfaces.

Knowledge, perceptions and expectations of nurses in e-health: results of a survey in a children's hospital

We surveyed all nurses working at a tertiary paediatric hospital (except casual staff and those who were on leave) from 27 hospital departments. A total of 365 questionnaires were distributed. There were 40 questions in six sections: demographic details, knowledge of e-health, relevance of e-health to nursing profession, computing skills, Internet use and access to e-health education. A total of 253 surveys were completed (69%). Most respondents reported that that they had never had e-health education of any sort (87%) and their e-health knowledge and skills were low (71%). However, 11% of nurses reported some exposure to e-health through their work. Over half (56%) of respondents indicated that e-health was important, very important or critical for health professions while 26% were not sure. The lack of education and training was considered by most respondents (71%) to be the main barrier to adopting e-health. While nurses seemed to have moderate awareness of the potential benefits of e-health, their practical skills and knowledge of the topic were very limited.

Post-acute burns education via videoconference for occupational therapists in Queensland

For over five years, post-acute burns care for children in regional areas of Queensland has been provided by videoconference. Some 300 specialist burns consultations are conducted by videoconference annually. To support regional health professionals, particularly occupational therapists who play an integral role in the local management of these children, we have instigated a series of monthly education sessions via videoconference. The sessions have addressed a broad range of topics related to the long-term management of children following a burn injury. During the first six months, up to 22 regional sites participated in multipoint videoconferences. The average number of participants per videoconference was 39 and the average duration of each session was 67 min. Participant satisfaction was measured with a routine survey completed by each site at the conclusion of the videoconference. The survey response rate was 88% (n = 95) and overall feedback was extremely positive. 96% of respondents agreed that the programme provided them with new information and that the content was relevant (95%) and of appropriate depth (84%). The educational programme has provided valuable support to a group of professionals who are taking on greater responsibility for the clinical management of children requiring post-acute burns care.

A comparison of telepaediatric activity at two regional hospitals in Queensland

We conducted a 15-month feasibility study of telepaediatrics. A novel service was offered to two hospitals in Queensland (Mackay and Hervey Bay). We used data from all other hospitals throughout the state as the control group. Although both intervention hospitals were provided with the same service, the telepaediatric activity generated and the effect on admissions and outpatient activity were markedly different. There was a significant decrease in the number of patient admissions to Brisbane from the Mackay region. In addition, there was an increase in the number of Mackay patients treated locally (as outpatients). In contrast, little change was observed in Hervey Bay. We assessed whether the observed differences between the two hospitals were due to various factors which influenced the use of the telepaediatric service. These factors included the method of screening patients before transfer to the tertiary centre and the physical distance between each facility and the tertiary centre. We believe that the screening method used for patient referrals was the most important determinant of the use of the telepaediatric service.

Child development services: a multidisciplinary approach to professional education via videoconference

We have piloted a monthly series of multidisciplinary case discussions via videoconference in the area of child development. The project provided a forum for clinical discussion of complex cases, peer review, professional development and networking for allied health professionals and paediatricians. Six sites in Queensland participated in the project; each site presented at least one case for discussion. The videoconferences ran for 90 min each and were attended by an average of 26 health professionals. The response rate for a questionnaire survey was 71%. The respondents rated the effectiveness of case summaries and the follow-up newsletter very positively. Despite some early difficulties with the technical aspects of videoconferencing, the evaluation demonstrated the participants' satisfaction with the project and its relevance to their everyday practice.

Logistical aspects of large telemedicine networks. 2: Measurement of network activity

We carried out a retrospective review of the videoconference activity records in a university-run hospital telemedicine studio. Usage records describing videoconferencing activity in the telemedicine studio were compared with the billing records provided by the telecommunications company. During a seven-month period there were 211 entries in the studio log: 108 calls made from the studio and 103 calls made from a far-end location. We found that 103 calls from a total of 195 calls reported by the telecommunications company were recorded in the usage log. The remaining 92 calls were not recorded, probably for one of several reasons, including: failed calls-a large number of unrecorded calls (57%) lasted for less than 2 min (median 1.6 min); origin of videoconference calls-calls may have been recorded incorrectly in the usage diary (i.e. as being initiated from the far end, when actually initiated from the studio); and human error. Our study showed that manual recording of videoconference activity may not accurately reflect the actual activity taking place. Those responsible for recording and analysing videoconference activity, particularly in large telemedicine networks, should do so with care.

Structure, dynamics, and energetics of siRNA-cationic vector complexation:a molecular dynamics study

The design and synthesis of safe and efficient nonviral vectors for gene delivery has attracted significant attention in recent years. Previous experiments have revealed that the charge density of a polycation (the carrier) plays a crucial role in complexation and the release of the gene from the complex in the cytosol. In this work, we adopt an atomistic molecular dynamics simulation approach to study the complexation of short strand duplex RNA with six cationic carrier systems of varying charge and surface topology. The simulations reveal detailed molecular-level pictures of the structures and dynamics of the RNA-polycation complexes. Estimates for the binding free energy indicate that electrostatic contributions are dominant followed by van der Waals interactions. The binding free energy between the 8(+)polymers and the RNA is found to be larger than that of the 4(+)polymers, in general agreement with previously published data. Because reliable binding free energies provide an effective index of the ability of the polycationic carrier to bind the nucleic acid and also carry implications for the process of gene release within the cytosol, these novel simulations have the potential to provide us with a much better understanding of key mechanistic aspects of gene-polycation complexation and thereby advance the rational design of nonviral gene delivery systems.

Flexibility of short-strand RNA in aqueous solution as revealed by molecular dynamics simulation:are A′-RNA and A-RNA distinct conformational structures?

We use molecular dynamics simulations to compare the conformational structure and dynamics of a 21-base pair RNA sequence initially constructed according to the canonical A-RNA and A'-RNA forms in the presence of counterions and explicit water. Our study aims to add a dynamical perspective to the solid-state structural information that has been derived from X-ray data for these two characteristic forms of RNA. Analysis of the three main structural descriptors commonly used to differentiate between the two forms of RNA namely major groove width, inclination and the number of base pairs in a helical twist over a 30 ns simulation period reveals a flexible structure in aqueous solution with fluctuations in the values of these structural parameters encompassing the range between the two crystal forms and more. This provides evidence to suggest that the identification of distinct A-RNA and A'-RNA structures, while relevant in the crystalline form, may not be generally relevant in the context of RNA in the aqueous phase. The apparent structural flexibility observed in our simulations is likely to bear ramifications for the interactions of RNA with biological molecules (e.g. proteins) and non-biological molecules (e.g. non-viral gene delivery vectors). © CSIRO 2009.

Reducible disulfide-based non-viral gene delivery systems

The design and synthesis of safe efficient non-viral vectors for gene delivery has attracted significant attention in recent years due primarily to the severe side-effect profile reported with the use of their viral counterparts. Previous experiments have revealed that the strong interaction between the carriers and nucleic acid may well hinder the release of the gene from the complex in the cytosol adversely affecting transfection efficiency. However, incorporating reducible disulfide bonds within the delivery systems themselves which are then cleaved in the glutathione-rich intracellular environment may help in solving this puzzle. This review focuses on recent development of these reducible carriers. The biological rationale and approaches to the synthesis of reducible vectors are discussed in detail. The in vitro and in vivo evaluations of reducible carriers are also summarized and it is evident that they offer a promising approach in non-viral gene delivery system design.

Structure and dynamics of multiple cationic vectors-siRNA complexation by all-atomic molecular dynamics simulations

Understanding the molecular mechanism of gene condensation is a key component to rationalizing gene delivery phenomena, including functional properties such as the stability of the gene-vector complex and the intracellular release of the gene. In this work, we adopt an atomistic molecular dynamics simulation approach to study the complexation of short strand duplex RNA with four cationic carrier systems of varying charge and surface topology at different charge ratios. At lower charge ratios, polymers bind quite effectively to siRNA, while at high charge ratios, the complexes are saturated and there are free polymers that are unable to associate with RNA. We also observed reduced fluctuations in RNA structures when complexed with multiple polymers in solution as compared to both free siRNA in water and the single polymer complexes. These novel simulations provide a much better understanding of key mechanistic aspects of gene-polycation complexation and thereby advance progress toward rational design of nonviral gene delivery systems.