Sample-size dependence of the ground-state energy in a one-dimensional localization problem

We study the sample-size dependence of the ground-state energy in a one-dimensional localization problem, based on a supersymmetric quantum mechanical Hamiltonian with random Gaussian potential. We determine, in the form of bounds, the precise form of this dependence and show that the disorder-average ground-state energy decreases with an increase of the size $R$ of the sample as a stretched-exponential function, $\exp( - R^{z})$, where the characteristic exponent $z$ depends merely on the nature of correlations in the random potential. In the particular case where the potential is distributed as a Gaussian white noise we prove that $z = 1/3$. We also predict the value of $z$ in the general case of Gaussian random potentials with correlations.Comment: 30 pages and 4 figures (not included). The figures are available upon reques

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Arthroscopic Piriformis Release—A Technique for Sciatic Nerve Decompression

Various techniques for piriformis muscle release have been published previously. However, it is imperative we continue to improve on existing techniques as well as develop new ones that may further optimize outcomes. Therefore, we aimed to describe an endoscopic technique for the release of the piriformis muscle in those with symptoms of sciatic nerve compression. Using the posterolateral portal, we are able to perform a complete release of the piriformis from the greater trochanter and the piriformis fossa with care to protect the external rotators and the sciatic nerve. It is our belief that this technique can be easily replicated by practitioners who read this technical note

Iliotibial Band Lengthening: An Arthroscopic Surgical Technique

Iliotibial (IT) band syndrome is a common cause of lateral knee pain in runners and cyclists. Many can be treated nonoperatively; however, some may require surgical lengthening of their IT band to achieve optimal pain relief and a return to preinjury level of activity. Several studies have been published detailing surgical lengthening procedures and satisfactory outcomes after these procedures. However, it is important to continue to improve on and optimize outcomes. We present our arthroscopic IT band–lengthening procedure

Patella Footprint Technique—A Surgical Method for Medial Patellofemoral Ligament Reconstruction

Recurrent patella instability is a common condition that may potentiate substantial knee dysfunction resulting in loss of time from work and sports. There are numerous factors that contribute to recurrent patella instability including tearing of the medial patellofemoral ligament (MPFL), shallow trochlea, valgus alignment, externally rotated tibia tubercle, ligamentous laxity, elevated Q angle, and increased tibial tuberosity trochlear groove distance. Reconstruction of the MPFL has been shown to restore patella stability where concomitant pathology is within acceptable limits. Major complications include recurrence from inadequate MPFL reconstruction or failure to address other pathology, patella femoral pain from over constrained MPFL or unaddressed cartilage defects to the patella femoral compartment, or patella fracture. This technique provides a reproducible method of restoring patella stability through MPFL reconstruction while minimizing stress risers in the patella by using suture anchor fixation that creates a ligamentous footprint instead of tendon healing into a socket on the patella

Activities related to inflammatory bowel disease management during and after the coronavirus disease 2019 lockdown in Italy: How to maintain standards of care

Background and aims:Restructuring activities have been necessary during the lockdown phase of the coronavirusdisease 2019 (COVID-19) pandemic. Few data are available on the post-lockdown phase in terms of health-careprocedures in inflammatory bowel disease (IBD) care, and no data are available specifically from IBD units. Weaimed to investigate how IBD management was restructured during the lockdown phase, the impact of therestructuring on standards of care and how Italian IBD units have managed post-lockdown activities.Methods:A web-based online survey was conducted in two phases (April and June 2020) among the Italian Groupfor IBD affiliated units within the entire country. We investigated preventive measures, the possibility of continuingscheduled visits/procedures/therapies because of COVID-19 and how units resumed activities in the post-lockdownphase.Results:Forty-two referral centres participated from all over Italy. During the COVID-19 lockdown, 36% of first visitsand 7% of follow-up visits were regularly done, while>70% of follow-up scheduled visits and 5% of first visits weredone virtually. About 25% of scheduled endoscopies and bowel ultrasound scans were done. More than 80% ofbiological therapies were done as scheduled. Compared to the pre-lockdown situation, 95% of centres modifiedmanagement of outpatient activity, 93% of endoscopies, 59% of gastrointestinal ultrasounds and 33% of biologicaltherapies. Resumption of activities after the lockdown phase may take three to six months to normalize. Virtualclinics, implementation of IBD pathways and facilities seem to be the main factors to improve care in the future.Conclusion:Italian IBD unit restructuring allowed quality standards of care during the COVID-19 pandemic to bemaintained. A return to normal appears to be feasible and achievable relatively quickly. Some approaches, suchas virtual clinics and identified IBD pathways, represent a valid starting point to improve IBD care in the post-COVID-19 er