Data blinding for the nEDM experiment at PSI.

Psychological bias towards, or away from, prior measurements or theory predictions is an intrinsic threat to any data analysis. While various methods can be used to try to avoid such a bias, e.g. actively avoiding looking at the result, only data blinding is a traceable and trustworthy method that can circumvent the bias and convince a public audience that there is not even an accidental psychological bias. Data blinding is nowadays a standard practice in particle physics, but it is particularly difficult for experiments searching for the neutron electric dipole moment (nEDM), as several cross measurements, in particular of the magnetic field, create a self-consistent network into which it is hard to inject a false signal. We present an algorithm that modifies the data without influencing the experiment. Results of an automated analysis of the data are used to change the recorded spin state of a few neutrons within each measurement cycle. The flexible algorithm may be applied twice (or more) to the data, thus providing the option of sequentially applying various blinding offsets for separate analysis steps with independent teams. The subtle manner in which the data are modified allows one subsequently to adjust the algorithm and to produce a re-blinded data set without revealing the initial blinding offset. The method was designed for the 2015/2016 measurement campaign of the nEDM experiment at the Paul Scherrer Institute. However, it can be re-used with minor modification for the follow-up experiment n2EDM, and may be suitable for comparable projects elsewhere.

Thiel-embalmed porcine placenta: A valid and reusable microsurgical practice model.

BACKGROUND: Simulation models are increasingly important for skill acquisition during microsurgery training. Prosthetics, living and non-living biological models have been proposed in the literature in the optics of recreating real-life scenarios in a controlled environment. This study aims to validate and prove the reusability of a novel non-living biological model: the porcine placenta. METHODS: A prospective comparative study was carried out to assess face and content validities of the proposed model, as well as the reusability and quality of the Thiel-embalming method. Participants were asked answer a questionnaire for each anastomosis they performed on porcine placental vessels of ≤2mm (small) and 2-4mm (large). Scores were classified according to different subgroups, either small or large vessels and first or second sessions. Reliability analysis of the questionnaire was carried out using Cronbach's α, to ensure an α>0.7. Median scores for each question were analyzed using boxplots and compared amongst each subgroup using a non-parametric independent Mann-Whitney U test. RESULTS: With nine participants, the Cronbach's α for each category of question was 0.867, 0.778, 0.720 and 0.593. Statistical differences were found between responses of small and large vessels on 5/10 questions, where large vessels reported higher validity. No statistical differences were found between scores of the first and second sessions. CONCLUSION: By evaluating face and content validity, the Thiel-embalmed porcine placenta has proven its suitability as a microsurgery model, especially for vessels of larger caliber. Qualities that distinguish this model is its reliable reusability, its low cost-effectiveness, and its ethical acceptability.

Measurement of the Permanent Electric Dipole Moment of the Neutron.

We present the result of an experiment to measure the electric dipole moment (EDM) of the neutron at the Paul Scherrer Institute using Ramsey's method of separated oscillating magnetic fields with ultracold neutrons. Our measurement stands in the long history of EDM experiments probing physics violating time-reversal invariance. The salient features of this experiment were the use of a ^{199}Hg comagnetometer and an array of optically pumped cesium vapor magnetometers to cancel and correct for magnetic-field changes. The statistical analysis was performed on blinded datasets by two separate groups, while the estimation of systematic effects profited from an unprecedented knowledge of the magnetic field. The measured value of the neutron EDM is d_{n}=(0.0±1.1_{stat}±0.2_{sys})×10^{-26} e.cm.

Observation of Gravitationally Induced Vertical Striation of Polarized Ultracold Neutrons by Spin-Echo Spectroscopy.

We describe a spin-echo method for ultracold neutrons (UCNs) confined in a precession chamber and exposed to a |B0|=1 µT magnetic field. We have demonstrated that the analysis of UCN spin-echo resonance signals in combination with knowledge of the ambient magnetic field provides an excellent method by which to reconstruct the energy spectrum of a confined ensemble of neutrons. The method takes advantage of the relative dephasing of spins arising from a gravitationally induced striation of stored UCNs of different energies, and also permits an improved determination of the vertical magnetic-field gradient with an exceptional accuracy of 1.1 pT/cm. This novel combination of a well-known nuclear resonance method and gravitationally induced vertical striation is unique in the realm of nuclear and particle physics and should prove to be invaluable for the assessment of systematic effects in precision experiments such as searches for an electric dipole moment of the neutron or the measurement of the neutron lifetime.

[A surgical follow-up platform to reduce complications in free flap surgery]. / Une plateforme de suivi chirurgical pour réduire les complications en reconstruction par lambeau libre.

STUDY OBJECTIVE: In 2007, the WHO adopted surgical safety as the theme for the 2nd global patient safety challenge. Measurement of surgical services was identified as a surgical care area in need of major improvements. Aware of this recommendation, a preliminary study was conducted in our hospital and showed that the incidence of complete necrosis in free flap surgery was 10.0 %, a rate among the highest found in medical literature. In that context, an interactive surgical follow-up platform (PICS) was implemented to monitor outcomes in free flap surgery. The hypothesis was to reduce the short-term failure of microsurgical reconstructions. PATIENTS AND METHODS: In Summer 2010, the tool for capturing and analyzing data (PICS) was implemented. All patients who underwent free flap reconstruction were prospectively registered in the platform. The primary endpoints to evaluate the effectiveness of the tool are the rates of surgical re-exploration and complete necrosis of the flap. RESULTS: From May 2010 to December 2011, 129 cases of free flap reconstruction were recorded. The rate of total flap necrosis was 10.0 % before database introduction and declined to 3.1 % afterwards (P<0.05). Take-backs occurred in 27.0 % of free flap reconstructions at baseline and in 10.1 % after implementation (P<0.01). CONCLUSION: The implementation of PICS is associated with a significant improvement of postoperative short-term outcomes in free flap surgery. This tool is effective to evaluate care services and provides an increased surgical safety for patients. Surgical teams are encouraged to implement a data collection tool in order evaluate operative care on a routine basis.

Achieving ultra-low and -uniform residual magnetic fields in a very large magnetically shielded room for fundamental physics experiments.

High-precision searches for an electric dipole moment of the neutron (nEDM) require stable and uniform magnetic field environments. We present the recent achievements of degaussing and equilibrating the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute. We present the final degaussing configuration that will be used for n2EDM after numerous studies. The optimized procedure results in a residual magnetic field that has been reduced by a factor of two. The ultra-low field is achieved with the full magnetic-field-coil system, and a large vacuum vessel installed, both in the MSR. In the inner volume of ∼1.4m3, the field is now more uniform and below 300 pT. In addition, the procedure is faster and dissipates less heat into the magnetic environment, which in turn, reduces its thermal relaxation time from 12h down to 1.5h.

[Interventional angioradiology as a solution for microsurgical flap failure]. / La radioangiologie interventionnelle comme solution de sauvetage en microchirurgie.

The microsurgical failure rate is almost constant for several decades. We present two case reports describing a novel method of free flap salvage using angioradiological techniques. Our first case shows the potential utility of in situ thrombolysis, our second case describes the first use of stents within a microsurgical anastomosis. In boths cases, the flap would have been lost immediately, because flap revisions failed. Thus, before abandoning on a flap, one could perform a simple angiography to evaluate further angioradiological salvage possibilities and hereby contribute to improve long term microsurgical failure rate.

A review of utilities and costs of treating upper extremity amputations with vascularized composite allotransplantation versus myoelectric prostheses in Canada.

Background: Hand vascularized composite allotransplantation (VCA) and myoelectric prostheses have proven their efficacy for treating hand amputation. Despite reported functional outcomes, the lack of consensus on VCA versus myoelectric prostheses brought us to report on their utilities and costs within the Canadian healthcare system. Methods: A review of utility outcomes and costs was performed for VCA and myoelectric prostheses and a comparison between unilateral versus bilateral amputations was made. Results: The simulation model demonstrated that significant savings could be achieved with both hand transplantation ($10.04 billion) and myoelectric prostheses ($12.17 billion) in all Canadian patients sustaining hand amputation with a 30-year life expectancy., Myoelectric prosthesis had lowest total cost compared to hand VCA by generating savings of $4,458,445,840 and $1,868,121,840 when compared to bilateral and unilateral upper limb amputations respectively. Conclusion: Treatment of unilateral amputations with myoelectric prostheses would cost significantly less to the society, whereas the gap in cost savings becomes less significant in bilateral amputees. From the socioeconomic standpoint of the Canadian healthcare system, this simulation model demonstrates that significant savings can be achieved with both treatments.

The very large n2EDM magnetically shielded room with an exceptional performance for fundamental physics measurements.

We present the magnetically shielded room (MSR) for the n2EDM experiment at the Paul Scherrer Institute, which features an interior cubic volume with each side of length 2.92 m, thus providing an accessible space of 25 m3. The MSR has 87 openings of diameter up to 220 mm for operating the experimental apparatus inside and an intermediate space between the layers for housing sensitive signal processing electronics. The characterization measurements show a remanent magnetic field in the central 1 m3 below 100 pT and a field below 600 pT in the entire inner volume, up to 4 cm to the walls. The quasi-static shielding factor at 0.01 Hz measured with a sinusoidal 2 µT peak-to-peak signal is about 100 000 in all three spatial directions and increases rapidly with frequency to reach 108 above 1 Hz.

The design of the n2EDM experiment: nEDM Collaboration.

We present the design of a next-generation experiment, n2EDM, currently under construction at the ultracold neutron source at the Paul Scherrer Institute (PSI) with the aim of carrying out a high-precision search for an electric dipole moment of the neutron. The project builds on experience gained with the previous apparatus operated at PSI until 2017, and is expected to deliver an order of magnitude better sensitivity with provision for further substantial improvements. An overview is of the experimental method and setup is given, the sensitivity requirements for the apparatus are derived, and its technical design is described.

Search for Lorentz invariance and CPT violation with the MINOS far detector.

We searched for a sidereal modulation in the MINOS far detector neutrino rate. Such a signal would be a consequence of Lorentz and CPT violation as described by the standard-model extension framework. It also would be the first detection of a perturbative effect to conventional neutrino mass oscillations. We found no evidence for this sidereal signature, and the upper limits placed on the magnitudes of the Lorentz and CPT violating coefficients describing the theory are an improvement by factors of 20-510 over the current best limits found by using the MINOS near detector.

[Residency in plastic surgery: comparison between the French and the Canadian Royal College programs]. / L'apprentissage de la chirurgie plastique :comparaison de la formation française et duprogramme de résidence canadien du Collège royal.

BACKGROUND: Learning plastic surgery in Montreal is different from learning plastic surgery in a French university. In Canada, all residency programs are accredited by a national structure: the Royal College of Physicians and Surgeons. We tried to highlight the differences that exist between the French and a North American academic system. MATERIAL AND METHOD: With the different rules and law that governs academic education in both countries, we analyzed the following elements: the residency selection, the program of plastic surgery (content and organisation), the system of evaluation and the diplomas. RESULT: The training of a Canadian plastic surgeon is very controlled. The recommendations of the Royal College guarantee to the resident who enters a program to have the means to acquire a complete training in quantity and in quality. On the four studied items, none is completely similar between both countries. Each having advantages and inconveniences as, for example, the selection of residency by interview or by the classifying national exam. CONCLUSION: Actually, few French plastic surgery programs could satisfy the requirements of the Royal College on several points, however without failing the training of French plastic surgeons. Nevertheless, we could be inspired by several elements (rotation in private practice,grouping together several academic hospitals. . .) to improve our system of training.

Comparative analysis between scientific and the media communication following facial transplantation.

PURPOSE: Our aim was to analyze the communications about three outstanding medical reports. Was there any difference in the reports of the three allografts? Was there a correlation between the media and the scientific world? METHODS: The Internet sites of three major newspapers were used for the media database. Those results were compared with PubMed between 2005 and 2007 using these key words: "facial graft," "facial allograft," "composite tissue allograft," and names of surgeons of the graft. We did a comparative analysis using a word processor and a quality analysis software. RESULTS: We analyzed 51 articles from the media and six from the PubMed database. In PubMed, 100% of the articles were on the first graft and respected the privacy of the patient compared to 67% of the media who unveiled the identity. CONCLUSION: The communication following a medical premiere depends on the team, which performes the act. We observed a major difference between the three cases. Ethical considerations are different for the media and for scientists. The communication management of a medical premiere takes preparation and evaluation.

[Is muscle the best coverage for leg Gustilo IIIb fractures? A retrospective comparative study]. / Le muscle est-il la meilleure couverture pour les fractures ouvertes de jambe Gustillo IIIb ? Etude rétrospective comparative.

UNLABELLED: Well-vascularized muscle flaps have been the traditional gold standard for coverage of open fracture of the lower extremity. The last 15 years have brought the fasciocutaneous and perforator flaps and raised the issue of the type of coverage required for open fracture of the lower extremity. In recent years, in selected compromised patient, we have been using nonmuscular flaps for reconstruction. The goal of this study is to compare the results of fasciocutaneous reconstruction to those of classical muscular flaps. PATIENTS AND METHODS: A comparative retrospective study, including all patients from 2002 to 2006 requiring a coverage of a Gustillo III b fracture of the lower extremity, is done. The type of flaps, the fracture localization, the infection rate, the time required for consolidation of the fracture and the complication rate are reviewed. An independent university laboratory verified the statistical analysis. RESULTS: Twenty patients have experienced coverage by muscular flaps and 18 by fasciocutaneous flaps. We found a skin fistula and a chronic infection in the muscular-flap group, and two skin fistulae in the fasciocutaneous flaps group. The overall surgical results were comparable, except the bony union delay shorter in the fasciocutaneous flaps group. CONCLUSION: Muscle coverage is not mandatory to cover bone in the lower leg. The fasciocutaneous flaps can provide a good alternative for muscle-flap coverage. There is no significant difference as far as consolidation and infection are concerned, between the coverage by muscular or fasciocutaneous flaps.

French translation and cross-cultural adaptation of the Michigan Hand Outcomes Questionnaire and the Brief Michigan Hand Outcomes Questionnaire.

Patient-Reported Outcome Measures (PROMs) are important clinical devices for evaluating injuries and surgeries of the hand. However, some of the most widely used questionnaires, such as the MHQ and bMHQ, are currently unavailable in French, which prevents them from being used in the French Canadian province of Quebec as well as in other French-speaking nations. We therefore intend to develop valid and culturally adapted French translations of the afore-mentioned questionnaires. Two independent bilingual translators converted all English questionnaires to French. Two distinct translators then translated the French versions back to English in reverse-blinded fashion. Discrepancies between the original and second English versions were examined by a committee of four bilingual healthcare professionals before final French translations of all documents were produced. Thirty patients bilingual in French and English were then asked to complete the original and French versions of the MHQ and bMHQ. Their answers were compared in order to assess the accuracy of our translation. In light of these findings, revised French versions were produced. French versions of the MHQ and bMHQ questionnaires produced metrological qualities of validity and fidelity with an inter-class correlation superior to 0.90 and a kappa coefficient of 0.81 to 1. Clinical applicability revealed the distribution of scores according to disease process was reproducible between the English and French versions. PROM translation requires a rigorous process in order to achieve strong metrological qualities in both the original and translated versions. We produced French translations of the MHQ and bMHQ by abiding to the Beaton method of cross-cultural adaptation of self-reported measures.

"Trigger finger at the wrist" due to anomalous flexor digitorum superficialis muscle belly within the carpal tunnel.

"Triggering of the fingers at the wrist" is a relatively unusual condition. It consists in a triggering at the wrist produced by finger motion. Its etiology and presentation may vary. This condition should be clearly differentiated from the other clinical entity called "trigger wrist", occurring on wrist movement. In the present article, we report the case of an anomalous flexor digitorum superficialis muscle belly, arising from the right ring finger at the carpal tunnel, in a 47-year old female patient, causing triggering of the right ring finger at the wrist and a carpal tunnel syndrome. Surgical excision of the muscle mass and carpal tunnel release relieved patient's symptoms and has led to the disappearance of the triggering phenomenon. To date, few cases of trigger finger at the wrist have been reported in the literature. These reported cases were reviewed. The clinical entity of "true trigger wrist" and its etiology are also discussed.

Impact of the number of veins repaired in short-term digital replantation survival rate.

BACKGROUND: Venous congestion/insufficiency plays a major role in failure of finger replantation. Despite acceptable salvage rates with postoperative anticoagulation or leeching, operative technique remains the most important predictor of success. However, there are no indications in the literature on the benefit of anastomosing single versus multiple veins. METHODS: A retrospective review of finger amputations from 2011 to 2013 was conducted. The analyzed endpoint was the finger survival rate at discharge depending on the number of veins repaired: multiple veins (group 1), only one vein (group 2), or no veins (group 3). Proportions were compared using v2 tests/Fisher's exact tests; p-value <0.05 was considered significant. RESULTS: Seventy-two patients with complete digital amputation were operated including 101 fingers. Twenty-seven fingers (26.7%) failed before hospital discharge, with 78% of failures due to venous complications versus 22% with an arterial etiology. Group 2 had 15 replantation failures due to venous causes as opposed to only one from group 1, representing a 1.27-fold (95% confidence interval (CI): 0.99, 1.34) increased relative risk of failure (p = 0.032). Similarly, five fingers from group 3 suffered venous complications, resulting in a 1.49-fold (95% CI: 1.02, 1.73) increased likelihood of failure in comparison to group 1 (p = 0.008). No significant difference was observed between having only one vein repaired versus none (RR: 1.1792, 95% CI: 0.83, 2.10, p = 0.502). CONCLUSION: Efforts toward favoring two-vein repair lead to better survival of the replanted fingers. More cases need to be analyzed before formulating conclusions on specific levels of amputation with regard to venous anastomoses.

Replantation vs revision amputation in single digit zone II amputations.

The objective of this study was to compare the functional outcomes of zone II amputations treated with either replantation or revision amputation at our institution to better aid patients in their decision making process regarding these treatment options. We conducted a comparative retrospective study. All cases of single digit amputations received at our replantation center between 2007 and 2011 were screened for single digit zone II injuries. These patients were stratified based on the treatment received: replantation vs revision amputation. Patients were called and invited to participate in the research project. Those who accepted to enter the study were asked to complete the Quick-DASH, the Beck Depression Inventory-short form, and a custom made questionnaire. There were seventeen patients with single digit zone II replantation and fourteen patients with similar injuries who underwent revision amputation and agreed to take part in the study. Our data revealed that the duration of sick leave, occupation after injury, professional and social reintegration, discontinued activities, and self-confidence were not statistically different between the two groups. The average hospital stay and the follow-up period of replanted individuals were longer. The replantation group did not have higher levels of pain or cold intolerance, and the global functional and esthetic satisfaction levels were similar between the two groups. Also, Beck Depression Inventory and Quick-DASH scores were not statistically different. Yet, significantly more patients in the replantation group would opt to repeat the replantation than revised patients would opt for revision amputation. From a functional viewpoint, our study suggests that revision amputation is not superior to replantation in zone II single digit amputations. This is valuable information that should be given to patients when deciding on the treatment process and to insure a proper informed consent.

Patient acceptance as a factor in the effectiveness of treatment: an open assessment of potassium clorazepate ('Tranxene') and lorazepam in anxiety.

Two new benzodiazepines, potassium clorazepate (15 mg. at night), and lorazepam (1 mg. t.d.s.) were compared in 50 patients presenting with anxiety in general practice. The response to treatment was assessed clinically and for patient acceptance. The single-dose regime of potassium clorazepate was significantly better, both for clinical effectiveness and patient acceptance. In the potassium clorazepate treated group there were significantly fewer side-effects. In particular, sedation was a problem with lorazepam, 6 patients stopping treatment and 8 voluntarily reducing the dose. Only 2 patients stopped treatment because of the sedative effect of potassium clorazepate. The sedative effects also show qualitative differences: in patients who completed the assessment lorazepam caused mainly daylong sedation and potassium clorazepate mid-day sedation, and when asked for their opinion on the value of sedation, only the potassium clorazepate group considered it to be beneficial.