To advance the field of soft robotics, a unified database of material constitutive models and experimental characterizations is of paramount importance. This will facilitate the use of finite element analysis to simulate their behavior and optimize the design of soft-bodied robots. Samples from seventeen elastomers, namely Body Double™ SILK, Dragon Skin™ 10 MEDIUM, Dragon Skin 20, Dragon Skin 30, Dragon Skin FX-Pro, Dragon Skin FX-Pro + Slacker, Ecoflex™ 00–10, Ecoflex 00–30, Ecoflex 00–50, Rebound™ 25, Mold Star™ 16 FAST, Mold Star 20T, SORTA-Clear™ 40, RTV615, PlatSil ^® Gel-10, Psycho Paint ^® , and SOLOPLAST 150318, were subjected to uniaxial tensile tests according to the ASTM D412 standard. Sample preparation and tensile test parameters are described in detail. The tensile test data are used to derive parameters for hyperelastic material models using nonlinear least-squares methods, which are provided to the reader. This article presents the mechanical characterization and the resulting material properties for a wide set of commercially available hyperelastic materials, many of which are recognized and commonly applied in the field of soft robotics, together with some that have never been characterized. The experimental raw data and the algorithms used to determine material parameters are shared on the Soft Robotics Materials Database GitHub repository to enable accessibility, as well as future contributions from the soft robotics community. The presented database is aimed at aiding soft roboticists in designing and modeling soft robots while providing a starting point for future material characterizations related to soft robotics research.

Importance The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer. Observations Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts. Conclusions and Relevance The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes.

#### What you need to know Acute appendicitis is the most common abdominal surgical emergency in the world, with around 50 000 and 300 000 acute appendicectomies performed annually in the UK and in the US respectively.12 However, its incidence is falling for unknown reasons.34 This clinical update provides information on how patients may present and what investigations and treatments are available. Acute appendicitis can affect people of any age but is most common between the ages of 10 and 20 years.45 It is more common in males, although females are twice as likely to undergo an appendicectomy.67 The lifetime risk of acute appendicitis is 8.6% in males and 6.9% in females; the lifetime appendicectomy rate is 12% in males and 23% in females.67 Perforation is found in 13-20% of patients with acute appendicitis.89 The aetiology remains uncertain,7910 but possible causes include luminal obstruction blocking the escape of mucosal secretions and leading to an increase in pressure, causing engorgement and stasis that can lead to necrosis and eventually perforation.79 Faecoliths, foreign bodies, malignancy, and lymphoid hyperplasia during an infection are described as possible causes of luminal obstruction.91112 There is no known genetic cause of acute appendicitis, but increased …

Objective: To compare techniques for rectal cancer resection. Summary Background Data: Different surgical approaches exist for mesorectal excision. Methods: Systematic literature review and Bayesian network meta-analysis performed. Results: Twenty-nine randomized controlled trials included, reporting on 6237 participants, comparing: open versus laparoscopic versus robotic versus transanal mesorectal excision. No significant differences identified between treatments in intraoperative morbidity, conversion rate, grade III/IV morbidity, reoperation, anastomotic leak, nodes retrieved, involved distal margin, 5-year overall survival, and locoregional recurrence. Operative blood loss was less with laparoscopic surgery compared with open, and with robotic surgery compared with open and laparoscopic. Robotic operative time was longer compared with open, laparoscopic, and transanal. Laparoscopic operative time was longer compared with open. Laparoscopic surgery resulted in lower overall postoperative morbidity and fewer wound infections compared with open. Robotic surgery had fewer wound infections compared with open. Time to defecation was longer with open surgery compared with laparoscopic and robotic. Hospital stay was longer after open surgery compared with laparoscopic and robotic, and after laparoscopic surgery compared with robotic. Laparoscopic surgery resulted in more incomplete or nearly complete mesorectal excisions compared with open, and in more involved circumferential resection margins compared with transanal. Robotic surgery resulted in longer distal resection margins compared with open, laparoscopic, and transanal. Conclusions: The different techniques result in comparable perioperative morbidity and long-term survival. The laparoscopic and robotic approaches may improve postoperative recovery, and the open and transanal approaches may improve oncological resection. Technique selection should be based on expected benefits by individual patient.

To assess the outcomes and patterns of treatment failure of patients who underwent pelvic exenteration surgery for recurrent rectal cancer. Despite advances in the management of rectal cancer, local recurrence still occurs. For appropriately selected patients, pelvic exenteration surgery can achieve long-term disease control. Prospectively maintained databases of 5 high volume institutions for pelvic exenteration surgery were reviewed and data combined. We assessed the combined endpoints of overall 5-year survival, cancer-specific 5-year mortality, local recurrence, and the development of metastatic disease. Five hundred thirty-three patients who had undergone surgery for locally recurrent rectal cancer were identified. Five-year cancer-specific survival for patients with a complete (R0) resection is 44%, which was achieved in 59% of patients. For those with R1 and R2 resections, the 5-year survival was 26% and 10%, respectively. Radical resection required sacrectomy in 170 patients (32%), and total cystectomy in 105 patients (20%). Treatment failure included local recurrence alone in 75 patients (14%) and systemic metastases with or without local recurrence in 226 patients (42%). Chemoradiotherapy before exenteration was associated with a significant (P < 0.05) improvement in overall 5-year cancer-specific survival for those patients with an R0 resection. Postoperative chemotherapy did not alter outcomes. R0 resection of the pelvic recurrence is the most significant factor affecting overall and disease-free survival. The surgery is complex and often highly morbid, and where possible patients should be given perioperative chemoradiotherapy. Further investigations are required to determine the role of adjuvant chemotherapy.