A Distributed Multilevel Force-directed Algorithm

The wide availability of powerful and inexpensive cloud computing services naturally motivates the study of distributed graph layout algorithms, able to scale to very large graphs. Nowadays, to process Big Data, companies are increasingly relying on PaaS infrastructures rather than buying and maintaining complex and expensive hardware. So far, only a few examples of basic force-directed algorithms that work in a distributed environment have been described. Instead, the design of a distributed multilevel force-directed algorithm is a much more challenging task, not yet addressed. We present the first multilevel force-directed algorithm based on a distributed vertex-centric paradigm, and its implementation on Giraph, a popular platform for distributed graph algorithms. Experiments show the effectiveness and the scalability of the approach. Using an inexpensive cloud computing service of Amazon, we draw graphs with ten million edges in about 60 minutes.Comment: Appears in the Proceedings of the 24th International Symposium on Graph Drawing and Network Visualization (GD 2016

Lack of regional pathways impact on surgical delay: Analysis of the Orthopaedic Trauma Hospital Outcomes-Patient Operative Delays (ORTHOPOD) study.

INTRODUCTION: Current practice following injury within the United Kingdom is to receive surgery, at the institution of first contact regardless of ability to provide timely intervention and inconsiderate of neighbouring hospital resource and capacity. This can lead to a mismatch of demand and capacity, delayed surgery and stress within hospital systems, particularly with regards to elective services. We demonstrate through a multicentre, multinational study, the impact of this at scale. METHODOLOGY: ORTHOPOD data collection period was between 22/08/2022 and 16/10/2022 and consisted of two arms. Arm 1 captured orthopaedic trauma caseload and capacity in terms of sessions available per centre and patients awaiting surgery per centre per given week. Arm 2 recorded patient and injury demographics, time of decision making, outpatient and inpatient timeframes as well as time to surgery. Hand and spine cases were excluded. For this regional comparison, regional trauma networks with a minimum of four centres enroled onto the ORTHOPOD study were exclusively analysed. RESULTS: Following analysis of 11,202 patient episodes across 30 hospitals we found no movement of any patient between hospitals to enable prompt surgery. There is no current system to move patients, between regional centres despite clear discrepancies in workload per capacity across the United Kingdom. Many patients wait for days for surgery when simple transfer to a neighbouring hospital (within 10 miles in many instances) would result in prompt care within national guidelines. CONCLUSION: Most trauma patients in the United Kingdom are managed exclusively at the place of first presentation, with no consideration of alternative pathways to local hospitals that may, at that time, offer increased operative capacity and a shorter waiting time. There is no oversight of trauma workload per capacity at neighbouring hospitals within a regional trauma network. This leads to a marked disparity in waiting time to surgery, and subsequently it can be inferred but not proven, poorer patient experience and outcomes. This inevitably leads to a strain on the overall trauma system and across several centres can impact on elective surgery recovery. We propose the consideration of inter-regional network collaboration, aligned with the Major Trauma System