Ripples at edges of blooming lilies and torn plastic sheets.

Ripples arise at edges of petals of blooming Lilium casablanca flowers and at edges of torn plastic sheets. In both systems, ripples are a consequence of excess length along the edge of a sheet. Through the use of time-lapse videos of blooming lilies and published images of torn plastic sheets, we find that ripples in both systems are well described by the scaling relationship a∝w(L-w), where a is amplitude, w is wavelength, and L is arc length. A phenomenological relationship previously reported for self-similar ripple patterns, namely ⟨a⟩∝⟨w⟩, can be recovered by assuming that buckling stress is constant. Excess length along petal edges can also influence their overall Gaussian curvature, such that petals invert from a cup shape to a saddle shape upon blooming. Previous simulations of these shape changes have assumed that petal thickness decreases at least quadratically. Here, we evaluate tomograms of several varieties of lily buds and find that this assumption is valid along the short axis of the buds, but not the long axis. A challenge of employing traditional tomography methods to measure petal thickness is that the sample is destroyed; a single bud cannot be followed through the entire blooming process. To address this challenge, we provide proof of principle that the nondestructive, label-free method of x-ray tomography produces high-contrast three-dimensional scans on time scales short enough to follow lily blooming.

Management trends and outcomes of pineal germinoma in a multi-institutional Australian cohort.

Pineal germinoma is rare with high cure rates following craniospinal radiotherapy. Efforts to reduce the radiotherapy dose and field via combination with chemotherapy suggest comparable disease control and reduced neurocognitive impairments, while the efficacy of immunotherapy in pineal germinoma remains undetermined. This report aimed to review clinical outcomes in patients treated for pineal germinoma in Queensland, Australia, and assess for Programmed Death-Ligand1 (PD-L1) expression. Patients who commenced radiation and/or chemotherapy for pineal germinoma from 2005 to 2017 were retrospectively identified using Queensland Oncology Online database. Demographic, diagnostic, treatment, and outcome data was obtained from electronic medical records. PD-L1 immuno-histochemistry was performed on available specimens. Eighteen patients with long-term follow-up data were identified. Median age at diagnosis was 16.8 years (range 9-46 years). Diagnosis was made histologically in fifteen patients, and radiologically in three. All patients underwent radiotherapy (median 36 Gy (range 21-54 Gy)) with lower median dose delivered with whole ventricle irradiation (12/18patients) than craniospinal irradiation (5/18patients). Sixteen patients received chemotherapy preceding radiotherapy. All patients are alive at median 7.25 years from primary treatment completion (range 2.03-13.1 years). Relapse occurred in three patients (16.67%) following treatment response, all of whom achieved remission following high-dose chemotherapy with stem-cell support and craniospinal radiotherapy. Post-treatment functional outcomes were similarly excellent. PD-L1 expression was low (1-49% cells) or negative in 87% of tumours tested but results were confounded by specimen quality and availability. Reduced-dose radiotherapy with chemotherapy does not compromise outcome and is standard of care at this institution. Immunotherapy is unlikely to become standard treatment in the near future.

Ceiling Fan-Related Head Injuries in Children: A Queensland Neurosurgical Experience.

INTRODUCTION: Ceiling fans are a widespread energy-efficient appliance required for managing the sweltering weather extremes encountered in northern Australian states including Queensland. Ceiling fans are also a rare cause of serious head injury in children requiring neurosurgical intervention. There is limited available evidence on the presentation, mechanism, and management of these injuries. METHODS: A retrospective analysis of children who suffered ceiling fan injuries admitted to the Queensland Children's Hospital, a level-1 paediatric trauma hospital in Brisbane, Queensland, under the neurosurgery unit from November 2014 to July 2018 was performed. RESULTS: Seventeen children (64.7% male) with a mean age of 4.24 years (range 0.66-7.25) sustained ceiling fan injuries requiring neurosurgical management during this period. Children were injured following being accidentally lifted or thrown into the ceiling fan path; jumping, playing, climbing, or being pushed from a bunk bed; or climbing on other furniture. All patients suffered skull fractures (88.2% depressed), and 65% suffered extra-axial or intracerebral haemorrhage. Operative management was required in 76.5% of the patients. No patients suffered adverse outcomes, and no complications, including infections, were recorded. CONCLUSIONS: Despite their rarity, paediatric ceiling fan injuries requiring neurosurgical management are a cause of significant morbidity. Surgical management targeted elevation of depressed fractures and washout of open fractures rather than evacuation of intracranial collections. Almost all included patients required transfer with associated social and economic implications. Such injuries are largely preventable with improved supervision and safety awareness. Hazard modification may be extended to regulatory changes or improved ceiling fan design.

Multifocal Gorham-Stout disease associated with Chiari I malformation and recurrent aseptic meningitis: Case report and review of literature.

Gorham-Stout disease is a rare condition of uncertain aetiology characterised by lymphatic proliferation within osseous structures and subsequent massive osteolysis. This report describes the index case of a patient with multifocal Gorham-Stout disease involving the skull base with Chiari I malformation and recurrent aseptic meningitis without fistula. A five-year-old male presented following decompression of a Chiari I malformation with headaches, vomiting, and stiff neck and cerebrospinal fluid pleocytosis without growth of a pathogenic organism. Ongoing symptoms prompted a further three presentations over several months revealing persistent aseptic cerebrospinal fluid monocytic pleocytosis. Further investigation revealed multifocal osseous cystic disease and subsequent bone biopsy suggested Gorham-Stout disease. Suboccipital decompression was not repeated despite craniocervical junction re-stenosis. A literature review demonstrated the extreme rarity of Gorham-Stout disease associated with Chiari I malformation and meningitis. Potential mechanisms of these entities occurring in concert are discussed. Consideration of Gorham-Stout disease as a secondary cause for Chiari I malformation is important amid local bone changes or cerebrospinal fluid leakage prior to pursuing suboccipital decompression considering the poor outcomes reported.

Traumatic brain injuries in a paediatric neurosurgical unit: A Queensland experience.

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality in children with a broad injury spectrum and associated continuum in the level of care required. A dearth of data exists regarding children requiring inpatient neurosurgical admission following TBI. A retrospective study of children 0-16 years-old admitted to the neurosurgical unit of a level-1 paediatric trauma hospital in Queensland, Australia following TBI was conducted focusing on the demographics, clinical characteristics, and management of these patients to guide those involved in their management, and identify areas for improvement in injury prevention and trauma system management. Over 48 months, 671 patients were identified (62.6% male) with median age 5.0 years, the majority transferred from peripheral centres. Falls (47.2%) and traffic accidents (21.5%) were the most common mechanisms. Non-displaced skull fracture was the most common injury. Moderate or severe TBI (GCS 3-12) was seen in 14.8% of whom were more likely to require surgery, intensive care, or suffer polytrauma. Clinically significant TBI, defined as moderate/severe TBI, polytrauma, death, requiring neurosurgery, intensive care admission, intubation, or admission three or more nights was detected in 57.97% with higher rates in transferred patients (62.9%) versus primary presentations (50.6%). Mechanisms involving low kinetic forces especially low-height falls and children with non-surgical pathology were less likely to meet criteria for clinically significant TBI. Opportunity exists to optimise triage and transfer practices within the trauma network to minimise the economic and social implications of over-triage with many children requiring only brief observation.

Diffuse midline glioma metastasis to the peritoneal cavity via ventriculo-peritoneal shunt: Case report and review of literature.

Extraneural dissemination of primary intracranial tumours to the peritoneal cavity via ventriculoperitoneal shunts is rare, with medulloblastoma and germ-cell tumours most common and gliomas seldom implicated. This report is the first described case of a diffuse midline glioma H3 K27M-mutant disseminating to the peritoneal cavity via a shunt. A four-year-old female presented with a large solid-cystic lesion centred on the suprasellar cistern, histologically revealed to be diffuse midline glioma H3 K27M-mutant. The patient received multiple courses of radiotherapy to the primary lesion and metachronous spinal metastases, and underwent bilateral ventriculoperitoneal shunts. She presented fourteen months following diagnosis with acute hydrocephalus and massive ascites revealed to be due to histologically confirmed intra-abdominal glioma metastasis secondary to shunting. Bilateral ventriculoatrial shunts along with targeted abdominal radiotherapy and repeated ascitic drainage were performed. The patient died one month later. A literature review demonstrated that intra-abdominal glioma metastasis is an extremely rare complication of cerebrospinal fluid diversion predominantly affecting paediatric patients with high-grade lesions within the first year after diagnosis and portends poor prognosis. Predisposition to metastasis is likely associated with tumour proximity to cerebrospinal fluid spaces and tumour biology. Contraindicating shunting in the presence of an intracranial tumour cannot be endorsed but rather shunt-related metastasis should be an acknowledged risk, and not-to-be-forgotten presentation.

SynMap2 and SynMap3D: web-based whole-genome synteny browsers.

SUMMARY: Current synteny visualization tools either focus on small regions of sequence and do not illustrate genome-wide trends, or are complicated to use and create visualizations that are difficult to interpret. To address this challenge, The Comparative Genomics Platform (CoGe) has developed two web-based tools to visualize synteny across whole genomes. SynMap2 and SynMap3D allow researchers to explore whole genome synteny patterns (across two or three genomes, respectively) in responsive, web-based visualization and virtual reality environments. Both tools have access to the extensive CoGe genome database (containing over 30 000 genomes) as well as the option for users to upload their own data. By leveraging modern web technologies there is no installation required, making the tools widely accessible and easy to use. AVAILABILITY AND IMPLEMENTATION: Both tools are open source (MIT license) and freely available for use online through CoGe ( https://genomevolution.org ). SynMap2 and SynMap3D can be accessed at http://genomevolution.org/coge/SynMap.pl and http://genomevolution.org/coge/SynMap3D.pl , respectively. Source code is available: https://github.com/LyonsLab/coge . CONTACT: ericlyons@email.arizona.edu. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Hashedcubes: Simple, Low Memory, Real-Time Visual Exploration of Big Data.

We propose Hashedcubes, a data structure that enables real-time visual exploration of large datasets that improves the state of the art by virtue of its low memory requirements, low query latencies, and implementation simplicity. In some instances, Hashedcubes notably requires two orders of magnitude less space than recent data cube visualization proposals. In this paper, we describe the algorithms to build and query Hashedcubes, and how it can drive well-known interactive visualizations such as binned scatterplots, linked histograms and heatmaps. We report memory usage, build time and query latencies for a variety of synthetic and real-world datasets, and find that although sometimes Hashedcubes offers slightly slower querying times to the state of the art, the typical query is answered fast enough to easily sustain a interaction. In datasets with hundreds of millions of elements, only about 2% of the queries take longer than 40ms. Finally, we discuss the limitations of data structure, potential spacetime tradeoffs, and future research directions.

Extracting Metrics for Three-dimensional Root Systems: Volume and Surface Analysis from In-soil X-ray Computed Tomography Data.

Plant roots play a critical role in plant-soil-microbe interactions that occur in the rhizosphere, as well as processes with important implications to climate change and crop management. Quantitative size information on roots in their native environment is invaluable for studying root growth and environmental processes involving plants. X-ray computed tomography (XCT) has been demonstrated to be an effective tool for in situ root scanning and analysis. We aimed to develop a costless and efficient tool that approximates the surface and volume of the root regardless of its shape from three-dimensional (3D) tomography data. The root structure of a Prairie dropseed (Sporobolus heterolepis) specimen was imaged using XCT. The root was reconstructed, and the primary root structure was extracted from the data using a combination of licensed and open-source software. An isosurface polygonal mesh was then created for ease of analysis. We have developed the standalone application imeshJ, generated in MATLAB(1), to calculate root volume and surface area from the mesh. The outputs of imeshJ are surface area (in mm(2)) and the volume (in mm(3)). The process, utilizing a unique combination of tools from imaging to quantitative root analysis, is described. A combination of XCT and open-source software proved to be a powerful combination to noninvasively image plant root samples, segment root data, and extract quantitative information from the 3D data. This methodology of processing 3D data should be applicable to other material/sample systems where there is connectivity between components of similar X-ray attenuation and difficulties arise with segmentation.