The design of a line velocity interferometer for any reflector for inertial confinement experiments on the Z-machine.

A line VISAR (Velocity Interferometer System for Any Reflector) has been designed and commissioned at the Sandia National Laboratory's Z-machine. The instrument consists of an F/2 collection system, beam transport, and an interferometer table that contains two Mach-Zehnder type interferometers and an eight channel Gated Optical Imaging (GOI) system. The VISAR probe laser operates at the 532 nm wavelength, and the GOI bandpass is 540-600 nm. The output of each interferometer is passed to an optical streak camera with four selectable sweep speeds. The system is designed with three interchangeable optics modules to select a full field of view of 1 mm, 2 mm, or 4 mm. The optical beam transport system connects the target image plane to the interferometers and the gated optical imagers. The target is integrated into a sacrificial final optics assembly that is integral to the transport beamline.

Saving Blood and Reducing Costs: Updating Blood Transfusion Practice in Lower Limb Arthroplasty

Aim Our aim was to quantify blood transfusion rates in lower limb arthroplasty following the introduction of a multimodal enhanced recovery programme (ERP). We then sought to update the maximum surgical blood ordering schedule (MSBOS) and calculate cost savings achieved. Methods A retrospective cohort study was conducted of all patients who required blood transfusion following primary and revision total hip and knee arthroplasty in 2012 and 2015. A multimodal ERP was introduced in 2015. Cost savings were calculated following the introduction of a new MSBOS. Results During the two-year study period 1467 lower limb arthroplasty procedures were performed. The cross-match to transfusion ratio was 3.6:1 in 2012 and 9.9:1 in 2015. The updated MSBOS resulted in a 46% reduction of cross-matched blood and savings of €54,375 per annum. Conclusion Improved perioperative management in lower limb arthroplasty has reduced blood transfusion rates. Updating blood transfusion practice can result in considerable savings in blood, resources and costs.

Fracture Patients' Attitudes towards Online Health Information & a 'Prescribed' Fracture Website

Introduction Following musculoskeletal injury patient education is essential to help patients understand their treatment. Many attend the orthopaedic fracture clinic with multiple questions related to their diagnosis and treatment. Aim To assess trauma patients' attitudes towards online health information and a specific orthopaedic patient information website. Methods A validated questionnaire was distributed over 5 consecutive clinics, with questions based on previous online experiences & www.myorthoclinic.com. Results One hundred six patients completed the survey. Seventy-one percent trusted the internet whereas 83% trusted the information provided by the website. Eighty-three percent felt encouraged to take action to benefit their health. Eighty-seven percent felt that there was a wide range of information provided. Seventy-two percent agreed that they learnt something new. Discussion Patients attending the trauma clinic have benefited from the 'prescribing' of a dedicated orthopaedic trauma website. This low-cost concept utilises minimal resources, requires little effort to implement and is applicable to all specialties.

Absorbable Polydioxanone (PDS) suture provides fewer wound complications than polyester (ethibond) suture in acute Tendo-Achilles rupture repair.

We prospectively studied acute Achilles tendon rupture in patients over a two 2-year period and reviewed the causes, outcome and complications. There were 53 patients included with acute Achilles rupture with minimum follow up period of 6 months. We compared the outcomes including infection rate and Boyden score between the two groups repaired by Polydioxanone and Polyester respectively. All infected cases had a suture repair using the polyester suture. The difference in the infection rate was highly significant between the 2 groups (p=0.001). All 34 patients (100%) in the PDS group had good / excellent results based on the Boyden clinical assessment. Conversely, only 16 patients 9(68.4%) had good or excellent results IN Polyester repair group. Patients treated with a non- absorbable suture (ethibond) material for repair had a higher incidence infection and worse Boyden scores than the absorbable PDS group.

Hill-Robertson interference maintained by Red Queen dynamics favours the evolution of sex.

Although it is well established theoretically that selective interference among mutations (Hill-Robertson interference) favours meiotic recombination, genomewide mean rates of mutation and strengths of selection appear too low to support this as the mechanism favouring recombination in nature. A possible solution to this discrepancy between theory and observation is that selection is at least intermittently very strong due to the antagonistic coevolution between a host and its parasites. The Red Queen theory posits that such coevolution generates fitness epistasis among loci, which generates negative linkage disequilibrium among beneficial mutations, which in turn favours recombination. This theory has received only limited support. However, Red Queen dynamics without epistasis may provide the ecological conditions that maintain strong and frequent selective interference in finite populations that indirectly selects for recombination. This hypothesis is developed here through the simulation of Red Queen dynamics. This approach required the development of a method to calculate the exact frequencies of multilocus haplotypes after recombination. Simulations show that recombination is favoured by the moderately weak selection of many loci involved in the interaction between a host and its parasites, which results in substitution rates that are compatible with empirical estimates. The model also reproduces the previously reported rapid increase in the rate of outcrossing in Caenorhabditis elegans coevolving with a bacterial pathogen.

Enhanced recovery in lower limb arthroplasty in the Irish setting.

BACKGROUND: In the current economic climate of staff shortages and bed closures, orthopaedic surgeons must look for system efficiencies. Enhanced Recovery Programmes (ERP) have the potential not only to reduce length of stay (LOS) and concurrent costs but also to improve patient outcomes. The aim of this paper is to evaluate the effect of ERP for primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) on length of stay (LOS) in the Irish Setting. METHODS: A single-surgeon retrospective case-control study was conducted comparing those who underwent primary lower limb arthroplasty before and after the introduction of an ERP. Patient medical and theatre records were used to determine the operation type, gender, age, LOS and readmission rates. RESULTS: Over the 2-year study period, a total of 310 patients underwent either THA (n = 244) or TKA (n = 66). The mean LOS was 8.79 days in the pre-ERP group and 5.1 days in the post-ERP group (p < 0.001). There was a significant correlation between LOS and age (p < 0.001). Gender or procedure type had no bearing on LOS for any of the subgroups (p > 0.1). CONCLUSIONS: ERP has the potential to significantly reduce overall length of stay after hip and knee arthroplasty and could have a considerable benefit in the Irish setting.

Simulated performance of the optical Thomson scattering diagnostic designed for the National Ignition Facility.

An optical Thomson scattering diagnostic has been designed for the National Ignition Facility to characterize under-dense plasmas. We report on the design of the system and the expected performance for different target configurations. The diagnostic is designed to spatially and temporally resolve the Thomson scattered light from laser driven targets. The diagnostic will collect scattered light from a 50 × 50 × 200 µm volume. The optical design allows operation with different probe laser wavelengths. A deep-UV probe beam (λ0 = 210 nm) will be used to Thomson scatter from electron plasma densities of ∼5 × 1020 cm-3 while a 3ω probe will be used for plasma densities of ∼1 × 1019 cm-3. The diagnostic package contains two spectrometers: the first to resolve Thomson scattering from ion acoustic wave fluctuations and the second to resolve scattering from electron plasma wave fluctuations. Expected signal levels relative to background will be presented for typical target configurations (hohlraums and a planar foil).

The design of the optical Thomson scattering diagnostic for the National Ignition Facility.

The National Ignition Facility (NIF) is a 192 laser beam facility designed to support the Stockpile Stewardship, High Energy Density and Inertial Confinement Fusion (ICF) programs. We report on the design of an Optical Thomson Scattering (OTS) diagnostic that has the potential to transform the community's understanding of NIF hohlraum physics by providing first principle, local, time-resolved measurements of under-dense plasma conditions. The system design allows operation with different probe laser wavelengths by manual selection of the appropriate beam splitter and gratings before the shot. A deep-UV probe beam (λ0-210 nm) will be used to optimize the scattered signal for plasma densities of 5 × 1020 electrons/cm3 while a 3ω probe will be used for experiments investigating lower density plasmas of 1 × 1019 electrons/cm3. We report the phase I design of a two phase design strategy. Phase I includes the OTS telescope, spectrometer, and streak camera; these will be used to assess the background levels at NIF. Phase II will include the design and installation of a probe laser.

Clinical beak and feather disease virus infection in wild juvenile eastern rosellas of New Zealand; biosecurity implications for wildlife care facilities.

CASE HISTORY: Four juvenile eastern rosellas (Platycercus eximius) were admitted to two separate wildlife care facilities in the Auckland region by members of the public. They had missing or dystrophic wing and tail feathers that rendered them flightless, suggestive of beak and feather disease virus (BFDV) infection. Two were subject to euthanasia after failing to re-grow their feathers, with samples taken for histopathology and PCR analysis. Blood samples were obtained from the other two birds at the time of examination, however these individuals were lost to follow up. PATHOLOGICAL AND MOLECULAR FINDINGS: Basophilic inclusion bodies were observed in histological sections of the feather bulb, typical of BFDV infection, from the two euthanised individuals. Blood from all four birds tested positive by PCR for BFDV, and analysis of the recovered full BFDV genomes identified them as belonging to the BFDV-A strain. DIAGNOSIS: Beak and feather disease virus infection. CLINICAL RELEVANCE: This report highlights the clinical impacts of BFDV in juvenile eastern rosellas that may result in their admission to wildlife care facilities, creating a biosecurity risk in institutions that may host other native parrots intended for release. The environmental stability of BFDV and resistance to disinfection requires strict quarantine procedures to prevent contamination and spread within a facility. It is recommended that high-risk species such as wild eastern rosella be excluded from facilities that may also house native parrots.

Case fatality ratio and mortality rate trends of community-onset Staphylococcus aureus bacteraemia.

Lethal outcomes can be expressed as a case fatality ratio (CFR) or as a mortality rate per 100 000 population per year (MR). Population surveillance for community-onset methicillin-sensitive (MSSA) and methicillin-resistant (MRSA) Staphylococcus aureus bacteraemia was conducted in Canada, Australia, Sweden and Denmark to evaluate 30-day CFR and MR trends between 2000 and 2008. The CFR was 20.3% (MSSA 20.2%, MRSA 22.3%) and MR was 3.4 (MSSA 3.1, MRSA 0.3) per 100 000 per year. Although MSSA CFR was stable the MSSA MR increased; MRSA CFR decreased while its MR remained low during the study. Community-onset S. aureus bacteraemia, particularly MSSA, is associated with major disease burden. This study highlights complementary information provided by evaluating both CFR and MR.

Outcomes of a patient recall following early failure of hip hemiarthroplasty.

BACKGROUND: Unexpected early loosening was noted in some patients who had bipolar hemiarthroplasties using aspecific combination of head and stem. AIM: A review of all patients who had received this implant combination was performed to establish whether there was a higher than expected failure rate and to identify those patients who had evidence of early loosening requiring further intervention or monitoring. METHODS: Theatre records were reviewed to identify those who had undergone bipolar hemiarthroplasty using these products. All surviving patients were contacted and offered an appointment at which they underwent clinical and radiological review. Following review, revision rates were compared to published Australian joint registry data. RESULTS: Of 247 eligible for recall, 139 attended for clinical and radiological review. The cumulative revision rate was 6.8 % at 4 years, with a mean time to revision of 26 months; however, there was a significantly higher revision rate of 12.1 % in those aged under 75 years at the time of surgery (p = 0.01). This is significantly higher than rates quoted for bipolar hemiarthroplasties in Australian joint registry data. CONCLUSION: Overall, higher than expected revision rates due to early loosening were seen for this product combination,especially in patients aged\75 years at the time of the initial surgery.

Population-based laboratory assessment of the burden of community-onset bloodstream infection in Victoria, Canada.

Although community-onset bloodstream infection (BSI) is recognized as a major cause of morbidity and mortality, its epidemiology has not been well defined in non-selected populations. We conducted population-based laboratory surveillance in the Victoria area, Canada during 1998-2005 in order to determine the burden associated with community-onset BSI. A total of 2785 episodes were identified for an overall annual incidence of 101·2/100,000. Males and the very young and the elderly were at highest risk. Overall 1980 (71%) episodes resulted in hospital admission for a median length of stay of 8 days; the total days of acute hospitalization associated with community-onset BSI was 28 442 days or 1034 days/100,000 population per year. The in-hospital case-fatality rate was 13%. Community-onset BSI is associated with a major burden of illness. These data support ongoing and future preventative and research efforts aimed at reducing the major impact of these infections.

The changing epidemiology of Staphylococcus aureus bloodstream infection: a multinational population-based surveillance study.

Although the epidemiology of Staphylococcus aureus bloodstream infection (BSI) has been changing, international comparisons are lacking. We sought to determine the incidence of S. aureus BSI and assess trends over time and by region. Population-based surveillance was conducted nationally in Finland and regionally in Canberra, Australia, western Sweden, and three areas in each of Canada and Denmark during 2000-2008. Incidence rates were age-standardized and gender-standardized to the EU 27-country 2007 population. During 83 million person-years of surveillance, 18,430 episodes of S. aureus BSI were identified. The overall annual incidence rate for S. aureus BSI was 26.1 per 100,000 population, and those for methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) were 24.2 and 1.9 per 100,000, respectively. Although the overall incidence of community-onset MSSA BSI (15.0 per 100,000) was relatively similar across regions, the incidence rates of hospital-onset MSSA (9.2 per 100,000), community-onset MRSA (1.0 per 100,000) and hospital-onset MRSA (0.8 per 100,000) BSI varied substantially. Whereas the overall incidence of S. aureus BSI did not increase over the study period, there was an increase in the incidence of MRSA BSI. Major changes in the occurrence of community-onset and hospital-onset MSSA and MRSA BSI occurred, but these varied significantly among regions, even within the same country. Although major changes in the epidemiology of community-onset and hospital-onset MSSA and MRSA BSIs are occurring, this multinational population-based study did not find that the overall incidence of S. aureus BSI is increasing.

Preoperative estimation of tibial nail length--because size does matter.

INTRODUCTION: Selecting the correct tibial nail length is essential for satisfactory outcomes. Nails that are inserted and are found to be of inappropriate length should be removed. Accurate preoperative nail estimation has the potential to reduce intra-operative errors, operative time and radiation exposure. METHODS: We compared the most commonly used radiological, anthropometric and intra-operative techniques to determine ideal nail lengths for 16 paired cadaveric tibiae. Five different anthropometric measurements were taken from each intact cadaver including: knee joint line to ankle joint line distance (JJD), medial knee joint line to medial malleolus distance (MMD), tibial tuberosity to medial malleolus distance (TMD), olecranon to 5th metacarpal head distance (OMD) and body height (BHR). Each tibia also underwent antero-posterior (AP) and lateral scanograms. Computerised tomography was used to determine the ideal nail length for each tibia. Each anthropometric and radiological measurement was recorded by two orthopaedic surgeons independently. An expert tibial nail was then inserted after nail length estimation was performed using a guidewire technique and an intra-operative radiographic ruler. RESULTS: The AP scanogram was found to be 100% accurate in selecting ideal nail length. The lateral scanogram was also found to be reasonably accurate but in 19% (3/16) of cases it led to a nail being too long. The intra-operative radiographic ruler was found to give a good indication of the ideal nail size, as did the guidewire technique, with only 6% (1/16) of cases producing an incorrect nail size. In general, the anatomical measurements gave a poor indication of ideal nail size compared with the other techniques. The following accuracies were noted: JJD 56%, MMD 50%, TMD 38%, BHR 13% and OMD 56%. CONCLUSIONS: We found that radiological methods such as using an AP radiograph with known magnification and intra-operative radiographic ruler were able to predict nail length very accurately and we suggest that these measurements should be performed routinely. The guidewire technique was also effective but we recommend that it not be used in isolation as errors can occur. We found that anatomical measurements are not accurate for predicting tibial nail length.

Operative outcomes for cervical myelopathy and radiculopathy.

Cervical spondylotic myelopathy and radiculopathy are common disorders which can lead to significant clinical morbidity. Conservative management, such as physical therapy, cervical immobilisation, or anti-inflammatory medications, is the preferred and often only required intervention. Surgical intervention is reserved for those patients who have intractable pain or progressive neurological symptoms. The goals of surgical treatment are decompression of the spinal cord and nerve roots and deformity prevention by maintaining or supplementing spinal stability and alleviating pain. Numerous surgical techniques exist to alleviate symptoms, which are achieved through anterior, posterior, or circumferential approaches. Under most circumstances, one approach will produce optimal results. It is important that the surgical plan is tailored to address each individual's unique clinical circumstance. The objective of this paper is to analyse the major surgical treatment options for cervical myelopathy and radiculopathy focusing on outcomes and complications.

H1N1 infection in emergency surgery: A cautionary tale.

Pandemic 2009 influenza A H1N1 has spread rapidly since its first report in Mexico in March 2009. This is the first influenza pandemic in over 40 years and it atypically affects previously healthy young adults, with higher rates of morbidity and mortality. The medical literature has been inundated with reports of H1N1 infection, the majority found in critical care and internal medicine journals with a relative paucity in the surgical literature. Despite this, it remains an important entity that can impact greatly on acute surgical emergencies. We present a case of previously healthy 31-year-old male who underwent open appendectomy. His post-operative recovery was complicated by acute respiratory distress syndrome secondary to H1N1 infection. This case report highlights the impact that H1N1 virus can have on acute surgical emergencies and how it can complicate the post-operative course.

Rapid turnover of spinules at synaptic terminals.

Spinules found in brain consist of small invaginations of plasma membranes which enclose membrane evaginations from adjacent cells. Here, we focus on the dynamic properties of the most common type, synaptic spinules, which reside in synaptic terminals. In order to test whether depolarization triggers synaptic spinule formation, hippocampal slice cultures (7-day-old rats, 10-14 days in culture) were exposed to high K+ for 0.5-5 min, and examined by electron microscopy. Virtually no synaptic spinules were found in control slices representing a basal state, but numerous spinules appeared at both excitatory and inhibitory synapses after treatment with high K+. Spinule formation peaked with approximately 1 min treatment at 37 degrees C, decreased with prolonged treatment, and disappeared after 1-2 min of washout in normal medium. The rate of disappearance of spinules was substantially slower at 4 degrees C. N-methyl-D-aspartic acid (NMDA) treatment also induced synaptic spinule formation, but to a lesser extent than high K+ depolarization. In acute brain slices prepared from adult mice, synaptic spinules were abundant immediately after dissection at 4 degrees C, extremely rare in slices allowed to recover at 28 degrees C, but frequent after high K(+) depolarization. High pressure freezing of acute brain slices followed by freeze-substitution demonstrated that synaptic spinules are not induced by chemical fixation. These results indicate that spinules are absent in synapses at low levels of activity, but form and disappear quickly during sustained synaptic activity. The rapid turnover of synaptic spinules may represent an aspect of membrane retrieval during synaptic activity.

Identifying individual scaffolding molecules in the postsynaptic density.

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 - August 7, 2008.

Focus-on-Teens, sexual risk-reduction intervention for high-school adolescents: impact on knowledge, change of risk-behaviours, and prevalence of sexually transmitted diseases.

A community-based intervention, Focus-on-Kids (FOK) has demonstrated risk-behaviour reduction of urban youth. We modified FOK to Focus-on-Teens (FOT) for high schools. High school adolescents (n=1190) were enrolled over successive school semesters. The small-group sessions were presented during the school-lunch hours. Confidential surveys were conducted at baseline, immediate, six-, and 12-month postintervention for demographics, parental communication/monitoring, sexual risk behaviours and sexually transmitted diseases (STDs)/HIV/condom-usage knowledge. Sexually active participants were encouraged to volunteer for urine-based STDs testing at the School-Based Health Centres. Many (47.4%) students reported having had sexual intercourse at baseline. Overall behaviours changed towards 'safer' sex behaviours (intent-to-use and using condoms, communicating with partner/parents about sex/condoms/STDs) with time (P<0.05). Proportion of students with complete correct knowledge of STDs/HIV increased to 88% at time 4 from 80% at baseline after adjusting for age, gender and sexual activity (P<0.05). High prevalence of STDs was detected in 875 participants who reported for urine testing at time 1: trichomonas, 11.8%; chlamydia, 10.1% and gonorrhoea, 4.1%. Prevalence decreased significantly for 310 participants who re-tested; chlamydia: 27.4% to 6.1% and gonorrhoea: 11.3% to 3.2%. FOT was successfully implemented as an STDs/HIV risk-reduction intervention. Sustained improvements of knowledge about STDs/HIV/condom usage, decreases in sexual risk behaviours supported the effectiveness of this intervention.

Nutrient profiles in retail cuts of bison meat.

The objectives were to determine the nutrient composition and variation in eight cuts of bison meat in bulls and heifers and identify nutrient relationships in the clod and sirloin by principal component analysis. The nutrients analyzed were: energy, protein, total fat, saturated fat, monounsaturated fat, polyunsaturated fat, transfat, cholesterol, vitamin A, Ca, Fe, Na and moisture. Differences were observed in fat components between cuts and bulls had higher (P<0.05) amounts of total, saturated, monounsaturated and polyunsaturated fat in the blade compared to the other cuts. The sirloins had less (P<0.05) cholesterol than all the other cuts in bulls and the clod in heifers. Fat varied more than protein and moisture in all cuts. Four principal components (PC) accounted for 63.9% of the total variation of the nutrient composition. Total, monounsaturated and saturated fats were in PC1 and cholesterol in PC2 showing that cholesterol is independent of other fats. If dietary alterations elicit changes in bison meat fatty acid profiles, it may be possible to reduce cholesterol independent of total, monounsaturated or saturated fat.