Balanced metrics on Cartan and Cartan-Hartogs domains

This paper consists of two results dealing with balanced metrics (in S. Donaldson terminology) on nonconpact complex manifolds. In the first one we describe all balanced metrics on Cartan domains. In the second one we show that the only Cartan-Hartogs domain which admits a balanced metric is the complex hyperbolic space. By combining these results with those obtained in [13] (Kaehler-Einstein submanifolds of the infinite dimensional projective space, to appear in Mathematische Annalen) we also provide the first example of complete, Kaehler-Einstein and projectively induced metric g such that $\alpha g$ is not balanced for all $\alpha >0$.Comment: 11 page

Conversion of laparoscopic colorectal resection for cancer: What is the impact on short-term outcomes and survival?

Laparoscopic resection for colon and rectal cancer is associated with quicker return of bowel function, reduced postoperative morbidity rates and shorter length of hospital stay compared to open surgery, with no differences in long-term survival. Conversion to open surgery is reported in up to 30% of patients enrolled in randomized control trials comparing open and laparoscopic colorectal resection for cancer. In this review, reasons for conversion are anatomical-related factors, disease-related-factors and surgeon-related factors. Body mass index, local tumour extension and co-morbidities are independent predictors of conversion. The current evidence has shown that patients with converted resection for colon cancer have similar outcomes compared to patients undergoing a laparoscopic completed or open resection. The few studies that have assessed the outcomes after conversion of laparoscopic rectal resection reported significantly higher rates of complications and longer length of hospital stay in converted patients compared to laparoscopically treated patients. No definitive conclusions can be drawn when converted and open rectal resections are compared. Early and pre-emptive conversion appears to have more favourable outcomes than reactive conversion; however, further large studies are needed to better define the optimal timing of conversion. With regard to long-term oncologic outcome, overall and disease-free survival in the case of conversion in laparoscopic colorectal cancer surgery seems to be worse than those achieved in patients in whom resection was successfully completed by laparoscopy. Although a worse long-term oncologic outcome has been suggested, it remains difficult to draw a proper conclusion due to the heterogeneity of the long-term outcomes as well as the inclusion of both colon and rectal cancer patients in most of the studies. Therefore, we discuss the currently available evidence of the impact of conversion in laparoscopic resection for colon and rectal cancer on both short-term outcomes and long-term survival

Actuation and stiffening in fluid-driven soft robots using low-melting-point material

Soft material robots offer a number of advantages over traditional rigid robots in applications including humanrobot interaction, rehabilitation and surgery. These robots can navigate around obstacles, elongate, squeeze through narrow openings or be squeezed - and they are considered to be inherently safe. The ability to stiffen compliant soft actuators has been achieved by embedding various mechanisms that are generally decoupled from the actuation principle. Miniaturisation becomes challenging due to space limitations which can in turn result in diminution of stiffening effects. Here, we propose to hydraulically actuate soft manipulators with lowmelting- point material and, at the same time, be able to switch between a soft and stiff state. Instead of allocating an additional stiffening chamber within the soft robot, one chamber only is used for actuation and stiffening. Low Melting Point Alloy is integrated into the actuation chamber of a single-compartment soft robotic manipulator and the interfaced robotic syringe pump. Temperature change is enabled through embedded nichrome wires. Our experimental results show higher stiffness factors, from 9-12 opposing the motion of curvature, than those previously found for jamming mechanisms incorporated in separate additional chambers, in the range of 2-8 for the same motion

Is the outpatient management of acute diverticulitis safe and effective? A systematic review and meta-analysis

Background: In Western countries, the incidence of acute diverticulitis (AD) is increasing. Patients with uncomplicated diverticulitis can undergo a standard antibiotic treatment in an outpatient setting. The aim of this systematic review was to assess the safety and efficacy of the management of acute diverticulitis in an outpatient setting. Methods: A literature search was performed on PubMed, Scopus, Embase, Central and Web of Science up to September 2018. Studies including patients who had outpatient management of uncomplicated acute diverticulitis were considered. We manually checked the reference lists of all included studies to identify any additional studies. Primary outcome was the overall failure rates in the outpatient setting. The failure of outpatient setting was defined as any emergency hospital admission in patients who had outpatient treatment for AD in the previous 60 days. A subgroup analysis of failure was performed in patients with AD of the left colon, with or without comorbidities, with previous episodes of AD, in patients with diabetes, with different severity of AD (pericolic air and abdominal abscess), with or without antibiotic treatment, with ambulatory versus home care unit follow-up, with or without protocol and where outpatient management is a common practice. The secondary outcome was the rate of emergency surgical treatment or percutaneous drainage in patients who failed outpatient treatment. Results: This systematic review included 21 studies including 1781 patients who had outpatient management of AD including 11 prospective, 9 retrospective and only 1 randomized trial. The meta-analysis showed that outpatient management is safe, and the overall failure rate in an outpatient setting was 4.3% (95% CI 2.6%-6.3%). Localization of diverticulitis is not a selection criterion for an outpatient strategy (p 0.512). The other subgroup analyses did not report any factors that influence the rate of failure: previous episodes of acute diverticulitis (p = 0.163), comorbidities (p = 0.187), pericolic air (p = 0.653), intra-abdominal abscess (p = 0.326), treatment according to a registered protocol (p = 0.078), type of follow-up (p = 0.700), type of antibiotic treatment (p = 0.647) or diabetes (p = 0.610). In patients who failed outpatient treatment, the majority had prolonged antibiotic therapy and only few had percutaneous drainage for an abscess (0.13%) or surgical intervention for perforation (0.06%). These results should be interpreted with some caution because of the low quality of available data. Conclusions: The outpatient management of AD can reduce the rate of emergency hospitalizations. This setting is already part of the common clinical practice of many emergency departments, in which a standardized protocol is followed. The data reported suggest that this management is safe if associated with an accurate selection of patients (40%); but no subgroup analysis demonstrated significant differences between groups (such as comorbidities, previous episode, diabetes). The main limitations of the findings of the present review concern their applicability in common clinical practice as it was impossible to identify strict criteria of failure

Is the outpatient management of acute diverticulitis safe and effective? A systematic review and meta-analysis

Background: In Western countries, the incidence of acute diverticulitis (AD) is increasing. Patients with uncomplicated diverticulitis can undergo a standard antibiotic treatment in an outpatient setting. The aim of this systematic review was to assess the safety and efficacy of the management of acute diverticulitis in an outpatient setting. Methods: A literature search was performed on PubMed, Scopus, Embase, Central and Web of Science up to September 2018. Studies including patients who had outpatient management of uncomplicated acute diverticulitis were considered. We manually checked the reference lists of all included studies to identify any additional studies. Primary outcome was the overall failure rates in the outpatient setting. The failure of outpatient setting was defined as any emergency hospital admission in patients who had outpatient treatment for AD in the previous 60 days. A subgroup analysis of failure was performed in patients with AD of the left colon, with or without comorbidities, with previous episodes of AD, in patients with diabetes, with different severity of AD (pericolic air and abdominal abscess), with or without antibiotic treatment, with ambulatory versus home care unit follow-up, with or without protocol and where outpatient management is a common practice. The secondary outcome was the rate of emergency surgical treatment or percutaneous drainage in patients who failed outpatient treatment. Results: This systematic review included 21 studies including 1781 patients who had outpatient management of AD including 11 prospective, 9 retrospective and only 1 randomized trial. The meta-analysis showed that outpatient management is safe, and the overall failure rate in an outpatient setting was 4.3% (95% CI 2.6%-6.3%). Localization of diverticulitis is not a selection criterion for an outpatient strategy (p 0.512). The other subgroup analyses did not report any factors that influence the rate of failure: previous episodes of acute diverticulitis (p = 0.163), comorbidities (p = 0.187), pericolic air (p = 0.653), intra-abdominal abscess (p = 0.326), treatment according to a registered protocol (p = 0.078), type of follow-up (p = 0.700), type of antibiotic treatment (p = 0.647) or diabetes (p = 0.610). In patients who failed outpatient treatment, the majority had prolonged antibiotic therapy and only few had percutaneous drainage for an abscess (0.13%) or surgical intervention for perforation (0.06%). These results should be interpreted with some caution because of the low quality of available data. Conclusions: The outpatient management of AD can reduce the rate of emergency hospitalizations. This setting is already part of the common clinical practice of many emergency departments, in which a standardized protocol is followed. The data reported suggest that this management is safe if associated with an accurate selection of patients (40%); but no subgroup analysis demonstrated significant differences between groups (such as comorbidities, previous episode, diabetes). The main limitations of the findings of the present review concern their applicability in common clinical practice as it was impossible to identify strict criteria of failure

Laparoscopic peritoneal lavage: A definitive treatment for diverticular peritonitis or a "bridge" to elective laparoscopic sigmoidectomy?

To this day, the treatment of generalized peritonitis secondary to diverticular perforation is still controversial. Recently, in patients with acute sigmoid diverticulitis, laparoscopic lavage and drainage has gained a wide interest as an alternative to resection. Based on this backdrop, we decided to perform a systematic review of the literature to evaluate the safety, feasibility, and efficacy of peritoneal lavage in perforated diverticular disease. A bibliographic search was performed in PubMed for case series and comparative studies published between January 1992 and February 2014 describing laparoscopic peritoneal lavage in patients with perforated diverticulitis. A total of 19 articles consisting of 10 cohort studies, 8 case series, and 1 controlled clinical trial met the inclusion criteria and were reviewed. In total these studies analyzed data from 871 patients. The mean follow-up time ranged from 1.5 to 96 months when reported. In 11 studies, the success rate of laparoscopic peritoneal lavage, defined as patients alive without surgical treatment for a recurrent episode of diverticulitis, was 24.3%. In patients with Hinchey stage III diverticulitis, the incidence of laparotomy conversion was 1%, whereas in patients with stage IV it was 45%. The 30-day postoperative mortality rate was 2.9%. The 30-day postoperative reintervention rate was 4.9%, whereas 2% of patients required a percutaneous drainage. Readmission rate after the first hospitalization for recurrent diverticulitis was 6%. Most patients who were readmitted (69%) required redo surgery. A 2-stage laparoscopic intervention was performed in 18.3% of patients. Laparoscopic peritoneal lavage should be considered an effective and safe option for the treatment of patients with sigmoid diverticulitis with Hinchey stage III peritonitis; it can also be consider as a “bridge” surgical step combined with a delayed and elective laparoscopic sigmoidectomy in order to avoid a Hartmann procedure. This minimally invasive staged approach should be considered for patients without systemic toxicity and in centers experienced in minimally invasive surgery techniques. Further evidence is needed, and the ongoing RCTs will better define the role of the laparoscopic peritoneal lavage/drainage in the treatment of patients with complicated diverticulitis

Soft Robotics. Bio-inspired Antagonistic Stiffening

Soft robotic structures might play a major role in the 4th industrial revolution. Researchers have demonstrated advantages of soft robotics over traditional robots made of rigid links and joints in several application areas including manufacturing, healthcare, and surgical interventions. However, soft robots have limited ability to exert larger forces and change their stiffness on demand over a wide range. Stiffness can be achieved as a result of the equilibrium of an active and a passive reaction force or of two active forces antagonistically collaborating. This paper presents a novel design paradigm for a fabric-based Variable Stiffness System including potential applications