Negative Price Forecasting in Australian Energy Markets using gradient-boosted Machines: Predictive and Probabilistic Analysis

With the integration of distributed energy resources such as roof-top solar panels and wind turbines into the grid, power generation can surpass demand-generation and thus, giving rise to the negative pricing, especially in the summer months. In this regard, a scientific case study is conducted in this paper to analyse and predict the increasing instances of negative energy prices against demand-generation in Australian energy markets (AEMs) using real-time energy data from the Hornsdale power reserve, South Australia. A robust machine learning method, Light gradient boosting machine (LightGBM) is utilised to detect and predict negative prices at different quantiles to quantity the outliers in the pricing data. The implementation results demonstrate that predicting the prices at different quantiles can tackle outliers (negative prices) effectively with the help of extracted upper and lower bounds using quantile regression-based approach. The case study is further extended to learn the complex statistical relationships between different data features using Naive-Bayes Tree Augmented (NB-TAN) algorithm considering ‘price’ as the dependent feature against the independent features such as demand-generation, battery charging/discharging, and frequency control ancillary services

Do Plastic Surgery Residents Get Sued? An Analysis of Malpractice Lawsuits

Background:. Trainees may be implicated in malpractice lawsuits. Our study examines malpractice cases involving plastic surgery trainees. Methods:. Using the LexisNexis database, verdicts and settlements from appellate state and federal cases between February 1988 and 2020 were queried. A nonrepresentative sample of 300 cases was compiled. Results:. During a 32-year period, 21 lawsuits involving plastic surgery trainees were identified. Of these, 14 (66.67%) involved claims when a trainee was directly named as a defendant. Eighteen (85.7%) cases were due to procedural-related adverse outcomes, while three (14.3%) cases were associated with clinical or diagnostic-related adverse outcomes. Of the procedure-related cases, five (27.8%) occurred when the trainee was the lead surgeon. Allegations included lack of informed consent of procedure complications (11, 52.4%), procedural error (11, 52.4%), failure to supervise trainee (11, 52.4%), inexperience of trainee (eight, 38.1%), incorrect diagnosis or treatment (five, 23.8%), delay in evaluation (three, 14.3%), lack of awareness of resident involvement (three, 14.3%), lack of follow-up (three, 14.3%), and prolonged operative time (one, 4.8%). Median time from injury to lawsuit resolution was 3.8 years [interquartile range (IQR), 3–5 years]. Verdicts were ruled in favor of the defense in eight (38.1%) cases and for plaintiff in six (28.6%) cases. A settlement was made in seven (33.3%) cases. Median payout for plaintiff-won cases was $5,100,000 (IQR,$1,530,000–$17,500,000); the median settlement was$2,500,000 (IQR, $262,500–$4,410,000). Conclusions:. Procedural error, improper informed consent, improper trainee supervision, and resident inexperience were the most common allegations. These factors can lead to financial and psychological burdens early in a physician’s career

Two-stage Prosthetic Prepectoral Breast Reconstruction: Comparing Tissue Expansion with Carbon Dioxide and Saline

Background:. The AeroForm tissue expander is a carbon dioxide-filled breast tissue expander that allows gradual, needle-free expansion using a hand-held remote controller. This study evaluates 2-stage, prepectoral tissue expander-to-implant breast reconstruction with the carbon-dioxide tissue expanders and compares the outcomes to our recent experience with saline tissue expanders. Methods:. This was a retrospective study of consecutive patients from a single institution. The subjects consisted of women who underwent mastectomy and either immediate or delayed breast reconstruction with AeroForm or saline tissue expanders. Outcomes encompassed postoperative complications including mastectomy flap necrosis, infection requiring readmission and/or intravenous antibiotics, capsular contracture, hematoma, seroma, skin dehiscence, extrusion, premature explant, and loss of communication with the device (AeroForm) or rupture of the device (saline). Results:. This study evaluated 115 patients with 185 breast reconstructions. Of the 185 breast reconstructions, 74 (40%) utilized AeroForm tissue expanders and 111 (60%) utilized traditional saline tissue expanders. Treatment was successful in 100% and 94% in the AeroForm and saline groups, respectively (P = 0.025). The incidence of adverse events was greater in the saline group (45.9% versus 32.4%). Surgical-site infection occurred more commonly in the saline group (5.4% versus 0%). Full-thickness skin necrosis occurred at a significantly higher rate in the saline cohort as compared with AeroForm (5.4% versus 0%). Conclusions:. The use of AeroForm tissue expanders offers notable advantages for breast reconstruction. This device when employed in the prepectoral space may be associated with reduced infection rates and decreased utilization of healthcare and patient resources

Utility of Indocyanine Green Fluorescence Lymphography in Identifying the Source of Persistent Groin Lymphorrhea

Summary: Surgical manipulation of the groin can result in lymphatic injury in a significant number of patients leading to poor wound healing or infectious complications. Surgical repair of lymphatic injury is greatly aided by the precise and prompt intraoperative localization of the injured lymphatic vessels. We assessed and identified lymphatic leaks in 2 cases of surgical wound lymphorrhea occurring after instrumentation of the groin using laser-assisted indocyanine green lymphography paired with isosulfan blue injection. Both cases healed without complication, and no lymphatic leak recurrence was observed during postoperative follow-up. Laser-assisted indocyanine green lymphography is a useful adjunct in the management of lymphatic leaks after surgery of the groin and may have potential for prophylactic evaluation of high-risk groin wounds

Effects of Self-management Program as Adjunctive to Usual Rehabilitation Exercise on Pain and Functional Outcomes in Knee Osteoarthritis: A Randomized Controlled Trial

Background: Home-based exercise (HBE) and patient education (EDU) have been reported as beneficial additions to usual knee osteoarthritis (KOA) rehabilitation. However, previous trials mostly examined the effects of HBE and EDU separately. Thus, this study aimed to evaluate the effects of a structured combined HBE and EDU program in addition to usual KOA rehabilitation on pain score, functional mobility, and disability level. Study Design: A parallel-group, single-blinded randomized controlled trial. Methods: Eighty adults with KOA were randomly allocated to experimental (n=40) and control (n=40) groups. All participants underwent their usual physiotherapy care weekly for eight weeks. The experimental group received a structured HBE+EDU program to their usual care, while the control group performed home stretching exercises to equate treatment time. The Knee Injury and Osteoarthritis Outcome Score (KOOS) for the disability level, visual analogue scale (VAS) for pain, and timed up-and-go test (TUG) for mobility were measured pre-post intervention. Results: After eight weeks, the experimental group demonstrated significant improvements in the KOOS (all subscales), pain VAS, and TUG scores compared to baseline (P<0.001); meanwhile, only KOOS (activities of daily living and sports subscales) was significant in the control group. Relative to the control, the experimental group presented higher improvements (P<0.001) by 22.2%, 44.1%, and 15.7% for KOOS, pain VAS, and TUG, respectively. Conclusion: Integrating the HBE+EDU program into usual KOA rehabilitation could reduce pain and disability, while it improved functional mobility. The finding of this study suggests a combination of a structured HBE and EDU program to be considered as part of mainstream KOA management