De-novo assembly of four rail (Aves: Rallidae) genomes: A resource for comparative genomics.

Rails are a phenotypically diverse family of birds that includes 130 species and displays a wide distribution around the world. Here we present annotated genome assemblies for four rails from Aotearoa New Zealand: two native volant species, pukeko Porphyrio melanotus and mioweka Gallirallus philippensis, and two endemic flightless species takahe Porphyrio hochstetteri and weka Gallirallus australis. Using the sequence read data, heterozygosity was found to be lowest in the endemic flightless species and this probably reflects their relatively small populations. The quality checks and comparison with other rallid genomes showed that the new assemblies were of good quality. This study significantly increases the number of available rallid genomes and will enable future genomic studies on the evolution of this family.

Study on monitoring broken rails of heavy haul railway based on ultrasonic guided wave.

Real-time monitoring of broken rails in heavy haul railways is crucial for ensuring the safe operation of railway lines. U78CrV steel is a common material used for heavy haul line rails in China. In this study, the semi-analytical finite element (SAFE) method is employed to calculate the dispersion curves and modal shapes of ultrasonic guided waves in U78CrV heavy steel rails. Guided wave modes that are suitable for detecting rail cracks across the entire cross-section are selected based on the total energy of each mode and the vibration energy in the rail head, web, and foot. The excitation method for the chosen mode is determined by analyzing the energy distribution of the mode shape on the rail surface. The ultrasonic guided wave (UGW) signal in the rail is analyzed using ANSYS three-dimensional finite element simulation. The group velocity of the primary mode in the guided wave signal is obtained through continuous wavelet transform to confirm the existence of the selected mode. It is validated that the selected mode can be excited by examining the similarity between the vibration shapes of a specific rail section and all modal vibration shapes obtained through SAFE. Through simulation and field verification, the guided wave mode selected and excited in this study demonstrates good sensitivity to cracks at the rail head, web, and foot, and it can propagate over distances exceeding 1 km in the rail. By detecting the reflected signal of the selected mode or the degree of attenuation of the transmitted wave, long-distance monitoring of broken rails in heavy-haul railway tracks can be achieved.

Stuck in a (literal) tight spot: Cycling between tram rails, sharrows and parked cars.

PROBLEM: Cyclists riding next to parked vehicles are at risk of crashes with opening vehicle doors. A central position, out of this dooring zone, decreases such a risk but comes with other problems like potentially smaller passing distances kept by overtaking motorists or having to cross tram rails. METHOD: Factors influencing cyclists' choice of position were investigated by showing a total of 3,444 German cyclists different traffic situations in two online surveys. In the first study (N = 1,850), parked cars, the position of a cyclist riding ahead in the presented images (towards the curb/center of the lane), and presence and kind of sharrows were varied. As the variation in results for the different sharrow types was negligible, in Study 2 (N = 1,594), only the most common type was used. Whether cyclists prefer to accept the risk of falling while crossing tram rails or the risk of being too close to the curb or parked cars was investigated, varying the presence of tram rails, which has not been previously researched. In both studies, respondents indicated which position on the road they would choose in the depicted situations and answered questions about subjective safety, a factor closely related to cyclists' choice of position. RESULTS: Cyclists chose positions farther towards the center of the road if there were parked cars and they chose an even more central position with tram rails. Respondents felt safer with sharrows on the road as well as in situations without parked cars and in situations without tram rails. Discussion and practical implications: The results indicate that, in addition to infrastructure characteristics, other cyclists' behavior (descriptive norm) influences cyclists' position on the road as well as their perceived safety. Implications for infrastructure design, especially regarding (the removal of) parked cars, are discussed.

King Rail (Rallus elegans) presence in the Midwestern United States is predicted by local-scale factors and avian community.

The King Rail (Rallus elegans) is a wetland dependent species of conservation concern. Our objective was to gain a better understanding of the breeding habitat associations of King Rails in the Midwestern United States and the relationship of this species to other obligate marsh birds using occupancy and MaxEnt models. To collect data pertaining to occupancy, we placed trail cameras at 50 random points in coastal wetlands in the western Lake Erie basin where calls of King Rails were continuously broadcast at night. Data pertaining to other marsh bird species were collected via call-broadcast surveys and camera surveys at each sample point. For MaxEnt modeling, we obtained presence data for King Rails and other obligate marsh birds from eBird and habitat data from GIS databases. Trail cameras and call-broadcast surveys captured 10 detections of King Rails at nine sites, an 18% naive occupancy rate. King Rail occupancy was positively related to amount of interspersion, average water depth, and percent cover of emergent vegetation at local scales within a 5-m radius. Our MaxEnt models indicated that, at a broader scale, the presence of other rail species such as the Sora (Porzana carolina) may be more important for predicting King Rail presence than other marsh birds or coarse wetland categories such as "emergent vegetation." Our results could help wetland managers to predict where King Rails occur and to adapt management plans to incorporate King Rail conservation.

Experimental Studies of Welded Joints in Structures Subject to High Impact Vibrations Using Destructive and Non-Destructive Methods.

This article presents the issues of control and quality assurance of high-strength railway rail joints. Selected test results and requirements for rail joints made by welding with stationary welders on the basis of the requirements included in the PN-EN standards have been described. In addition, destructive and non-destructive tests of weld quality were performed, including visual tests, geometrical measurements of irregularities, magnetic particle and penetration tests, fracture tests, observations of micro- and macro-structure and hardness measurements. The scope of these studies included conducting tests, monitoring the process and evaluating the results obtained. Laboratory tests on the rail joints confirmed the good quality of the rail joints from the welding shop. Increasingly less damage to the track in places of new welded joints is proof that the methodology of laboratory qualification tests is correct and fulfils its task. The presented research will help educate engineers on the welding mechanism and the importance of quality control of rail joints during their design. The results of this study are of key importance for public safety and will improve knowledge on the correct implementation of the rail joint and how to conduct quality control tests in accordance with the requirements of the currently applicable standards. It will help engineers choose the right welding technique and choose solutions to minimize cracks.

High-Speed railways and the spread of Covid-19.

High-speed railways (HSRs) greatly decrease transportation costs and facilitate the movement of goods, services, and passengers across cities. In the context of the Covid-19 pandemic, however, HSRs may contribute to the cross-regional spread of the new coronavirus. This paper evaluates the role of HSRs in spreading Covid-19 from Wuhan to other Chinese cities. We use train frequencies in 1971 and 1990 as instrumental variables. Empirical results from gravity models demonstrate that one more HSR train originating from Wuhan each day before the Wuhan lockdown increases the cumulative number of Covid-19 cases in a city by about 10 percent. The empirical analysis suggests that other transportation modes, including normal-speed trains and airline flights, also contribute to the spread of Covid-19, but their effects are smaller than the effect of HSRs. This paper's findings indicate that transportation infrastructures, especially HSR trains originating from a city where a pandemic broke out, can be important factors promoting the spread of an infectious disease.

Vibration-Based Approach to Measure Rail Stress: Modeling and First Field Test.

This paper describes a non-invasive inspection technique for the estimation of longitudinal stress in continuous welded rails (CWR) to infer the rail neutral temperature (RNT), i.e., the temperature at which the net longitudinal force in the rail is zero. The technique is based on the use of finite element method (FEM), vibration measurements, and machine learning (ML). FEM is used to model the relationship between the boundary conditions and the longitudinal stress of any given CWR to the vibration characteristics (mode shapes and frequencies) of the rail. The results of the numerical analysis are used to train a ML algorithm that is then tested using field data obtained by an array of accelerometers polled on the track of interest. In the study presented in this article, the proposed technique was proven in the field during an experimental campaign conducted in Colorado. A commercial FEM software was used to model the rail track as a short rail segment repeated indefinitely and under varying boundary conditions and stress. Three datasets were prepared and fed to ML models developed using hyperparameter search optimization techniques and k-fold cross validation to infer the stress or the RNT. The frequencies of vibration were extracted from the time waveforms obtained from two accelerometers temporarily attached to the rail. The results of the experiments demonstrated that the success of the technique is dependent on the accuracy of the model and the ability to properly identify the modeshapes. The results also proved that the ML was also able to predict successfully the neutral temperature of the tested rail by using only a limited number of experimental data for the training.

Low-Dose Computed Tomography Scanning Protocols for Online Adaptive Proton Therapy of Head-and-Neck Cancers.

PURPOSE: To evaluate the suitability of low-dose CT protocols for online plan adaptation of head-and-neck patients. METHODS: We acquired CT scans of a head phantom with protocols corresponding to CT dose index volume CTDIvol in the range of 4.2-165.9 mGy. The highest value corresponds to the standard protocol used for CT simulations of 10 head-and-neck patients included in the study. The minimum value corresponds to the lowest achievable tube current of the GE Discovery RT scanner used for the study. For each patient and each low-dose protocol, the noise relative to the standard protocol, derived from phantom images, was applied to a virtual CT (vCT). The vCT was obtained from a daily CBCT scan corresponding to the fraction with the largest anatomical changes. We ran an established adaptive workflow twice for each low-dose protocol using a high-quality daily vCT and the corresponding low-dose synthetic vCT. For a relative comparison of the adaptation efficacy, two adapted plans were recalculated in the high-quality vCT and evaluated with the contours obtained through deformable registration of the planning CT. We also evaluated the accuracy of dose calculation in low-dose CT volumes using the standard CT protocol as reference. RESULTS: The maximum differences in D98 between low-dose protocols and the standard protocol for the high-risk and low-risk CTV were found to be 0.6% and 0.3%, respectively. The difference in OAR sparing was up to 3%. The Dice similarity coefficient between propagated contours obtained with low-dose and standard protocols was above 0.982. The mean 2%/2 mm gamma pass rate for the lowest-dose image, using the standard protocol as reference, was found to be 99.99%. CONCLUSION: The differences between low-dose protocols and the standard scanning protocol were marginal. Thus, low-dose CT protocols are suitable for online adaptive proton therapy of head-and-neck cancers. As such, considering scanning protocols used in our clinic, the imaging dose associated with online adaption of head-and-neck cancers treated with protons can be reduced by a factor of 40.

Assessing the Suitability of Habitats for Porphyrio porphyrio indicus and Amaurornis phoenicurus in Urban Wetlands of Peninsular Malaysia.

It becomes imperative to understand the eco-climatic predictors and know the suitable habitat for Porphyrio porphyrio indicus and Amaurornis phoenicurus in the urban wetlands to prevent their local extinction. The study explored the habitat suitability for Porphyrio porphyrio indicus and Amaurornis phoenicurus in Paya Indah wetlands and Putrajaya wetlands of Peninsular Malaysia. Porphyrio porphyrio indicus and Amaurornis phoenicurus surveyed using the point count technique, and a stratified random design. The maximum entropy modelling (MEM) approach and geographic information systems employed to determine the influence of 17 eco-climatic factors on the suitable habitats for the species. Water at a minimum depth (44.30%) and rainfall (74.20%) contributed to the availability of suitable habitats for Porphyrio porphyrio indicus in Paya Indah and Putrajaya wetlands. Also, dissolved oxygen (56.60%) and salinity (43.50%) contributed to habitat suitability for Amaurornis phoenicurus in Paya Indah and Putrajaya wetlands. Large portions of the two urban wetlands were unsuitable for the Porphyrio porphyrio indicus and Amaurornis phoenicurus populations because of several eco-climatic factors. Thus, the models as management tools with a robust population monitoring database and framework would enhance the management effectiveness of the two species and urban wetlands.

Relationship between flightlessness and brain morphology among Rallidae.

Studies have suggested that the brain morphology and flight ability of Aves are interrelated; however, such a relationship has not been thoroughly investigated. This study aimed to examine whether flight ability, volant or flightless, affects brain morphology (size and shape) in the Rallidae, which has independently evolved to adapt secondary flightlessness multiple times within a single taxonomic group. Brain endocasts were extracted from computed tomography images of the crania, measured by 3D geometric morphometrics, and were analyzed using principal component analysis. The results of phylogenetic ANCOVA showed that flightless rails have brain sizes and shapes that are significantly larger than and different from those of volant rails, even after considering the effects of body mass and brain size respectively. Flightless rails tended to have a wider telencephalon and more inferiorly positioned foramen magnum than volant rails. Although the brain is an organ that requires a large amount of metabolic energy, reduced selective pressure for a lower body weight may have allowed flightless rails to have larger brains. The evolution of flightlessness may have changed the position of the foramen magnum downward, which would have allowed the support of the heavier cranium. The larger brain may have facilitated the acquisition of cognitively advanced behavior, such as tool-using behavior, among rails.

A comparative study using time-driven activity-based costing in single-fraction breast high-dose rate brachytherapy: An integrated brachytherapy suite vs. decentralized workflow.

INTRODUCTION: Precision breast intraoperative radiation therapy (PB-IORT) is a novel approach to adjuvant radiation therapy for early-stage breast cancer performed as part of a phase II clinical trial at two institutions. One institution performs the entire procedure in an integrated brachytherapy suite which contains a CT-on-rails imaging unit and full anesthesia capabilities. At the other, breast conserving surgery and radiation therapy take place in two separate locations. Here, we utilize time-driven activity-based costing (TDABC) to compare these two models for the delivery of PB-IORT. METHODS: Process maps were created to describe each step required to deliver PB-IORT at each institution, including personnel, equipment, and supplies. Time investment was estimated for each step. The capacity cost rate was determined for each resource, and total costs of care were then calculated by multiplying the capacity cost rates by the time estimate for the process step and adding any additional product costs. RESULTS: PB-IORT costs less to deliver at a distributed facility, as is more commonly available, than an integrated brachytherapy suite ($3,262.22 vs. $3,996.01). The largest source of costs in both settings ($2,400) was consumable supplies, including the brachytherapy balloon applicator. The difference in costs for the two facility types was driven by personnel costs ($1,263.41 vs. $764.89). In the integrated facility, increased time required by radiation oncology nursing and the anesthesia attending translated to the greatest increases in cost. Equipment costs were also slightly higher in the integrated suite setting ($332.60 vs. $97.33). CONCLUSIONS: The overall cost of care is higher when utilizing an integrated brachytherapy suite to deliver PB-IORT. This was primarily driven by additional personnel costs from nursing and anesthesia, although the greatest cost of delivery in both settings was the disposable brachytherapy applicator. These differences in cost must be balanced against the potential impact on patient experience with these approaches.

Dynamic assessment of the dose perturbation by sliding rails in intensity-modulated radiotherapy for spinal metastases / 中华放射医学与防护杂志

Objective:To investigate the impact of carbon based non-conductive sliding rails on intensity-modulated radiation therapy (IMRT) planning for vertebral tumors.Methods:A reconstruction imaging of the couch plate and its rails removed from the EDGE linear accelerator was acquired by helical computed tomography (CT), and pushed into the treatment planning system (TPS). Based on CT images of homogeneous phantom and patients in our database, 6 and 10 MV photon IMRT plans were designed with five fields (180°, 200°, 220°, 160°, 140°), setting a prescribed dose of 3 Gy/F ×10 F to the planning target volume (PTV), and the dose was calculated by AcruosXB. In addition, optimization plans (OP) without rails and with rails symmetrically moving (4-19 cm, step size 1 cm) were created and verification plans(VP) were created by inserting and removing slide rail′s structure from the corresponding OP in VP. The differences in mean dose ( Dmean), homogeneity index (HI), and conformability index (CI) of the PTV, and maximum dose ( Dmax) of the spinal cord were compared and analyzed between the VP and OP. Results:HI of PTV with and without the rails were worse in the 6/10 MV verification plans, with a maximum difference of 2%. In 6 MV plans, with rails Dmean of PTV decreased by (2.07±0.99)%, CI increased by (4.91±3.12)%, and Dmax of spinal cord decreased by (1.83±1.37)%. Without rails, the Dmean of PTV increased by (2.02±0.96)%, but CI decreased by (3.07±1.31)% and Dmax of the spinal cord increased by (2.03±1.44)% in the patient respectively. There were significant statistical differences between groupswith and without rails( F=27.55, 361.32, 13.05, P<0.05). The target volume Dmean and spinal cord Dmax decreased with a sloping " W" with the change of the rail position. The difference appeared to be noticeable in the range of less than 10 cm, but it gradually decreased as the rails slid to the outside until it reached zero, and the Dmean of PTV and Dmax of the spinal cordchanges were less in 10 MV plans, comparing to 6 MV plans. Conclusions:The dose attenuation by the sliding rails of the Qfix kVue should not ignored in the IMRT of spinal metastases and the slide position should be consistent with the planned position.

CT-on-Rails Versus In-Room CBCT for Online Daily Adaptive Proton Therapy of Head-and-Neck Cancers.

PURPOSE: To compare the efficacy of CT-on-rails versus in-room CBCT for daily adaptive proton therapy. METHODS: We analyzed a cohort of ten head-and-neck patients with daily CBCT and corresponding virtual CT images. The necessity of moving the patient after a CT scan is the most significant difference in the adaptation workflow, leading to an increased treatment execution uncertainty σ. It is a combination of the isocenter-matching σi and random patient movements induced by the couch motion σm. The former is assumed to never exceed 1 mm. For the latter, we studied three different scenarios with σm = 1, 2, and 3 mm. Accordingly, to mimic the adaptation workflow with CT-on-rails, we introduced random offsets after Monte-Carlo-based adaptation but before delivery of the adapted plan. RESULTS: There were no significant differences in accumulated dose-volume histograms and dose distributions for σm = 1 and 2 mm. Offsets with σm = 3 mm resulted in underdosage to CTV and hot spots of considerable volume. CONCLUSION: Since σm typically does not exceed 2 mm for in-room CT, there is no clinically significant dosimetric difference between the two modalities for online adaptive therapy of head-and-neck patients. Therefore, in-room CT-on-rails can be considered a good alternative to CBCT for adaptive proton therapy.

Dosimetric Evaluation of the QFix kVueTM Calypso Couch Top.

PURPOSE: To evaluate the dosimetric accuracy of the default couch model of the QFix kVueTM Calypso couch top in the treatment planning system. METHODS: With the gantry 180°, field size 20 × 20 cm, 6 MV, we measured the depth dose, off-axis dose, and dose plane of different depths in the phantom with the couch rails in and out, respectively. Isocenter doses at different angles were also obtained. The results were compared to the doses calculated using the default couch top model and the real scanned couch top model. Then we revised the default model according to the measured results. RESULTS: With "Rails In," the depth dose, off-axis dose, and dose plane of the default couch top model had a big difference with the dose of the real scanned couch top model and the measured result. The dose of the real scanned couch top model was much closer to the measured result, but in the region of the rail edge, the difference was still significant. With "Rails Out," there was a minor difference between the measured result, the dose of the default couch top model and the real scanned couch top model. The difference between the measurement and the default couch top model became very small after being revised. CONCLUSIONS: It is better to avoid the beam angle passing through the couch rails in treatment plans, or you should revise the parameter of the QFix kVueTM Calypso couch top model based on the measured results, and verify the treatment plan before clinical practice.

A preliminary study on enhancing safety of contact features in the terrain park.

OBJECTIVES: Terrain park riders use contact features such as fun boxes and rails. Typical fun box and rail features have a design characteristic that can be changed to improve safety. Fun box edge coping and edges of rails are typically constructed of soft steel. Ski/snowboard edges (HRC50) can easily become engaged in the softer metal, causing a chip to develop, suddenly stopping the rider, probably causing a fall and possible injury. The aim of the study is to examine the effect of terrain park running surface hardness on chip development. DESIGN: Testing on steel specimens was performed to research chip development generated by a ski/snowboard edge on steel used in the construction of contact features and on steel that is proposed for such use. An apparatus was constructed to simulate a ski/snowboard edge moving perpendicular to the long axis of coping or rail edge. METHODS: The author performed observation, photographic documentation, metallurgical testing and environmental testing of various contact features at different ski area terrain parks. Several steel specimens of varying hardness were tested at various load levels to study the propensity of chip development by ski/snowboard edges. RESULTS: Testing of steel samples showed that increasing the hardness of the rail steel or coping steel reduced the propensity for a ski/snowboard edge to engage in the coping or rail. CONCLUSIONS: Increasing steel coping and rail contact surface hardness to HRC 50 and above will likely reduce engagement by steel snowboard/ski edges, which in turn is expected to reduce the chance of a fall and injury.

Dosimetric evaluation of image-guided radiation therapy for prostate cancer.

The aim of this study was to investigate the dosimetric accuracy of imaged-guided radiation therapy for prostate patients using the in-room computed tomography (CT) target localization technique. A Siemens CT-on-rails system was used for patient setup and target localization for intensity-modulated radiation therapy (IMRT) of prostate cancer. Fifteen previously treated prostate patients were included in this retrospective study. CT-on-Rails scans were performed before and after the IMRT treatment under local IRB approval. A total of 15 original simulation CT scans and 98 post-treatment CT scans were contoured by the same oncologist to delineate the prostate target, bladder, and rectum. IMRT plans were generated on the original simulation CTs and the same MUs and leaf sequences were used to compute the dose distributions using post-treatment CTs. Varian Velocity deformable registration was used for the summation of the fractional doses and the cumulative doses were compared with the planned doses. For the 15 patients investigated, the mean isocenter shift was up to 4.0 mm in the left-right direction, 5.9 mm in the anterior-posterior direction and 5.6 mm in the superior-inferior direction due to interfractional organ motion. The mean rectal volume varied from 0.6 to 1.73 times and the mean bladder volume varied from 0.59 to 3.65 times between simulation and the end of treatment. The prescription dose to 95% of the PTV, Dp, was set to 76 Gy for all treatment plans. The dose to 95% of the clinical treatment volume (CTV), D95, was 74.0 to 77.6 Gy and the minimum CTV dose, Dmin, was 61.0 to 71.6 Gy, respectively, in the cumulative dose distributions. Detailed analyses showed that 7.1% of the treatment fractions had cold spots (< 85% of Dp) in the peripheral CTV, leading to Dmin < 64 Gy in the cumulative dose distributions for 4 patients. The rectal dose-volume constraints were violated in 35.7% of the treatment fractions while the bladder dose was much improved in 82.7% of the treatment fractions. The current IGRT procedure for patient setup and target localization using rigid-body registration based on contour/anatomy matching is effective for population-based PTV margins. For a small group of patients, specific PTV margins and/or real-time target monitoring/tracking will be necessary due to significant prostate deformation/rotation caused by inter- and intrafractional bladder and rectal volume variation.

An Improved Approach for the Control Measurements of a Ski-Flying Hill Inrun: A Case Study of Planica.

Ski jumping hills should be prepared for competitions in accordance with project documentation in order to ensure safe and fair conditions for competitors. Geodesy/surveying is essential for guiding preparations and controlling the actual shape of the hill. In this article, we present a methodology for the control measurements and preparation of an inrun for a ski-flying hill in Planica. On each side of the track, there is metal tube that guides the trolley, which mills tracks into the ice. A special platform containing three measuring prisms was designed to control the position of the tubes. The proposed method was thoroughly analyzed in terms of its measurement quality and compared to previously used methodologies. The empirical results suggest that our proposed platform provides inrun geometry with a higher quality than previously used methods.

Magnetic-Measuring Square in the Measurement of the Circular Curve of Rail Transport Tracks.

In rail transport, measuring the actual condition of a circular curve of a railway track is a key element of track position monitoring not only during operation but also during final works. Predicting changes in its position in the horizontal plane is one of the most important related scientific issues. This paper presents the results of measurements performed with an innovative measuring device called the Magnetic-Measuring Square (MMS). The aim of the research was to demonstrate the acceptability of using the MMS. Horizontal versines of a rail track curve were measured as three neighboring points on a curve (using the method of lacing/stringlining, also called the three-point or the Hallade method), and the perpendicularity of rail joints and shortenings were measured. The MMS device presented in this article was used to measure versines and differences in rails lengths (rail shortenings in the curve) in the operating mode involving a laser distance meter with a laser beam (laser power P < 1 mW, laser wavelength λ = 635 nm) with a target cross, a camera, and a surveying measuring disk. The measurement results confirmed that it is possible to employ the MMS to monitor the geometry of railway track fragments such as track transition curves and railway track curves in rail transport.

Systematics, morphology and ecology of rails (Aves: Rallidae) of the Mascarene Islands, with one new species.

Five species in five genera of extinct endemic rails have been described from the Mascarene Islands of Mauritius, Réunion and Rodrigues: the Mauritian Red Rail or Poule Rouge Aphanapteryx bonasia; Mascarene Coot or Poule d'eau Fulica newtonii; which occurred on Mauritius and Réunion; Réunion Wood Rail Dryolimnas augusti; Réunion Gallinule or Oiseaux bleu 'Porphyrio caerulescens'; and Rodrigues or Leguat's Rail Erythromachus leguati. All are known from fossil remains and/or from contemporary accounts and illustrations. A sixth species of rail Dryolimnas sp. nov. is described herein from fossils from Mauritius, but was not unequivocally previously reported in the contemporary literature. This paper provides an analysis of the Rallidae of the Mascarene Islands based on existing and newly discovered fossil remains, and details historical reports and accounts. Comprehensive osteological descriptions and synonymies are also included. Their ecology and extinction chronologies are interpreted from historical ev-idence. The relationships of Aphanapteryx and Erythromachus are unresolved, having clearly been isolated for a considerable time; the middle Miocene is the earliest their ancestors could have arrived on the Mascarenes, but this may have happened more recently. Mascarene derivatives of Fulica, Porphyrio and Dryolimnas are of much more recent origin, and appear to have originated in Africa or Madagascar. All terrestrial rails on Mauritius, Réunion and Rodrigues, were probable victims of cat predation following their historic introduction to the islands, whereas over-hunting by humans was probably the primary cause of extinction of 'Porphyrio caerulescens' on Réunion. The only extant rail on the Mascarenes today, the Madagascar race of Eurasian Moorhen Gallinula chloropus pyrrhorrhoa, is a recent arrival, having colonised Mauritius and Réunion after the extinction of Fulica newtonii.

'Off the rails': hospital bed rail design, contamination, and the evaluation of their microbial ecology.

Microbial contamination of the near-patient environment is an acknowledged reservoir for nosocomial pathogens. The hospital bed and specifically bed rails have been shown to be frequently and heavily contaminated in observational and interventional studies. Whereas the complexity of bed rail design has evolved over the years, the microbial contamination of these surfaces has been incompletely evaluated. In many published studies, key design variables are not described, compromising the extrapolation of results to other settings. This report reviews the evolving structure of hospital beds and bed rails, the possible impact of different design elements on microbial contamination and their role in pathogen transmission. Our findings support the need for clearly defined standardized assessment protocols to accurately assess bed rail and similar patient zone surface levels of contamination, as part of environmental hygiene investigations.