Assessing Nontrivial Topology in Weyl Semimetals by Dichroic Photoemission.

The electronic structure of Weyl semimetals features Berry flux monopoles in the bulk and Fermi arcs at the surface. While angle-resolved photoelectron spectroscopy (ARPES) is successfully used to map the bulk and surface bands, it remains a challenge to explicitly resolve and pinpoint these topological features. Here we combine state-of-the-art photoemission theory and experiments over a wide range of excitation energies for the Weyl semimetals TaAs and TaP. Our results show that simple surface-band-counting schemes, proposed previously to identify nonzero Chern numbers, are ambiguous due to pronounced momentum-dependent spectral weight variations and the pronounced surface-bulk hybridization. Instead, our findings indicate that dichroic ARPES provides an improved approach to identify Fermi arcs but requires an accurate description of the photoelectron final state.

Cost-utility of a six-month programmed sports therapy (PST) in patients with haemophilia.

INTRODUCTION: Recurrent musculoskeletal haemorrhages in people with haemophilia (PwH) lead to restrictions in the locomotor system and, as a result, in physical performance, too. Due to its physical and psychological benefits, sport is increasingly re-commended for haemophilic patients. Evidence on the cost-effectiveness of sports therapy is still lacking. AIM: The aim of this study was to determine the cost-effectiveness of a 6-month programmed sports therapy (PST). METHODS: The cost-effectiveness of the 6-month PST was assessed from a societal perspective alongside a RCT using cost-utility analysis. The analysis included 50 PwH with moderate-to-severe haemophilia A and B and a training period over 6 months. The health-related quality of life was measured with the EuroQoL-domain questionnaire. Resource utilization was assessed by questionnaire before and after the intervention. A cost-effectiveness acceptability curve was constructed, and sensitivity analyses were performed. RESULTS: During the 6-month study period, mean adjusted total healthcare costs were lower (mean difference: -22 805 EUR; 95%-CI: -73 944-48 463; P = .59) and the number of QALYs was higher in the intervention group (mean difference: 0.3733; 95%-CI: 0.0014-0.0573; P = .04). The probability of an incremental cost-effectiveness ratio <50 000 EUR per QALY was 71%. The performed sensitivity analysis confirmed these results. CONCLUSION: Results showed that the PST is effective in terms of a significant gain of QALYs. Furthermore, results weakly indicate the potential of the PST to reduce healthcare costs. Future studies should expand the observation period to have a closer look at the influence of PST on lifetime costs.

[Omitted spinal X-ray examination after a fall from a height of 3 m]. / Keine Röntgenuntersuchung der Wirbelsäule nach Sturz aus 3 m Höhe.

A 59-year-old patient with right-sided chest pains after a fall from a height of 3 m was referred to hospital by an emergency physician. The chest x-rays showed fractures of the third and seventh ribs on the right side. Inpatient analgesic therapy was initiated and after 3 days the patient was discharged from hospital for further outpatient treatment. As the pain persisted the patient consulted a surgeon 5 weeks later and the first X-ray examination of the spine was carried out which revealed the formation of several wedge-shaped thoracolumbar vertebral bodies. Further magnetic resonance imaging (MRI) diagnostics also revealed alterations to T10, T12, L1 and L3 as well as radiological signs of Scheuermann's disease; however, a definite statement differentiating these findings from older spinal fractures as a result of the accident was no longer possible. The patient claimed that the hospital failed to perform spinal X-ray investigations leading to prolonged pain and limitations in the quality of life. An external expert stated that the distracting injury of the ribs and the pain medication might have veiled the additional vertebral fractures. Thus, an earlier diagnosis of the apparently stable vertebral fractures would not have changed the conservative therapy approach. The decision of the arbitration board differed from the expert opinion as additional imaging techniques of the spine should have been initially performed due to the mechanism of injury. Although no irreversible damage to health resulted an earlier targeted treatment could have reduced the overall length of therapy.

[High-pressure injection injury of the hand. Underestimation of injury severity]. / Hochdruckinjektionsverletzung an der Hand. Unterschätzung der Verletzungsschwere.

A 44-year-old man sustained a high-pressure injection injury of the left index finger with hot hydraulic oil in an occupational accident. On presentation to the occupational physician 4 h later the wound was irrigated and cleaned. At this time X-ray diagnostics, wound revision, administration of antibiotics and immobilization were not performed. The following day the patient presented to a hospital with painful swelling and reddening of the left index finger where an emergency surgical wound revision, administration of antibiotics and immobilization of the finger were performed due to a phlegmon of the flexor tendon. Despite subsequent revision operations, necrosis of the flexor tendon sheath occurred with a skin subcutis defect necessitating a full thickness skin transplantation and ultimately operative fusion of the distal interphalangeal joint of the index finger. After a total period of treatment of 9 months the patient still presented with local soft tissue swelling and paresthesia as well as a limited range of motion of the proximal interphalangeal joint. The patient filed a complaint for wrong treatment of the high-pressure injection injury in terms of an inaccurate examination and lack of administration of antibiotics at the first presentation. The expert opinion of the arbitration board ascertained medical malpractice at the first presentation. An emergency surgical wound revision had already been indicated at the first presentation and the revision procedures would have been less extensive and it was highly probability that surgical fusion of the distal interphalangeal joint could have been avoided. The arbitration furthermore concluded that iatrogenic maltreatment led to a phlegmon of the flexor tendon with the need for subsequent revision operations including surgical fusion of the distal interphalangeal joint which resulted in an affected grip control. The delay in surgical treatment must be considered as the reason for the much worse initial situation that finally led to the functional impairment of the left index finger.

[Operation well performed but insufficiently documented and not indicated]. / Operation lege artis, jedoch mangelhaft dokumentiert und nicht indiziert.

A 50-year-old patient presented with a lump in the main joint of the fourth finger of the left hand, which was suspected of being malignant, for an operation. Following surgery the lump was still present and, furthermore, the patient reported a wound resulting from surgery on the third finger accompanied by swelling, pain and a loss of mobility. The patient accused the physician of performing surgery without indications on the wrong finger together with failure to remove the lump. The surgeon stated that lysis had been performed on the flexor tendon in the area of the lump. An external expert admonished the cursory surgery report; however, the expert stated that removal of the lump at the tendon would have been medically indicated and the operation was performed according to professional surgical standards. The decision of the arbitration board differed from the expert opinion as the insufficient documentation presented at first could have been understood to mean that a tendon node on the fourth finger was to be removed which was not the case. Furthermore, the operation performed would only have been indicated if a "trigger finger" were present; therefore, the surgery as well as the resulting afflictions and follow-up treatment were to be assessed as faulty. The handwritten surgery report had several shortcomings as well and led to a reversal of the burden of proof.

[Acute compartment syndrome after a bowling game]. / Kompartmentsyndrom nach Bowlingspiel.

A 28-year-old male patient was initially conservatively treated by a general physician for muscle strain of the right calf after a bowling game. Due to increasing pain and swelling of the lower leg 5 days later, the differential diagnosis of a deep vein thrombosis was considered. Furthermore, the onset of neurological deficits and problems with raising the foot prompted inclusion of compartment syndrome in the differential diagnosis for the first time. Admission to hospital for surgical intervention was scheduled for the following day. At this point in time the laboratory results showed a negative d-dimer value and greatly increased C-reactive protein level. On day 6 a dermatofasciotomy was performed which revealed extensive muscular necrosis with complete palsy of the peroneal nerve. In the following lawsuit the patient accused the surgeon of having misdiagnosed the slow-onset compartment syndrome and thus delaying correct and mandatory treatment. The arbitration board ruled that the surgeon should have performed fasciotomy immediately on day 5 at the patient's consultation. The clinical presentation of progressive pain, swelling of the lower leg in combination with peroneal palsy must lead to the differential diagnosis of compartment syndrome resulting in adequate therapy. The delay of immediate surgery, therefore, was assessed to be faulty as this knowledge is to be expected of a surgeon.

[Consequences of uncritical indication assessment for hardware removal]. / Folgen einer unkritischen Indikationsstellung der Metallentfernung.

A 43-year-old woman sustained a severe ankle dislocation with distal fibular fracture in a domestic accident. This was initially treated with external fixation for 3 weeks. In addition to distal fibular fracture treatment using a fixed-angle locking plate system, a vacuum-assisted wound closure of the medial und lateral malleolus had to be performed due to a persisting difficult soft tissue situation with swelling and necrosis of the medial malleolus. Subsequently, after prolonged wound healing the soft tissue defect over the distal fibula could be covered with a split skin graft and the external fixation was removed. Implant removal was performed 2 years after primary treatment - following radiologically confirmed consolidation of the fracture. Intraoperatively, an iatrogenic oblique fracture of the fibula occurred due to a cold welded screw in the plate, which had to be treated with lag screws. In the further course, there was renewed extensive wound healing with methicillin-resistant Staphylococcus aureus (MRSA) infection. The patient filed a complaint for the iatrogenic fibular fracture during hardware removal and also criticized the insufficient wound closure which led to an impairment of wound healing. The expert opinion of the arbitration board ascertained a medical malpractice in terms of indications. Due to the already prolonged course after the primary osteosynthesis hardware removal was not recommended. In addition, the surgical technique that led to the iatrogenic fracture was criticized. The arbitration board furthermore concluded that with a pre-existing osteoarthritis of the ankle, hardware removal was not indicated. In a critical wound situation implant removal would only be indicated with simultaneous treatment of the osteoarthritis of the ankle. By means of a critical indication assessment the patient should have been advised to leave the plate in place and the complicated course with iatrogenic fracture and severely delayed wound healing could have been avoided.

[Conservative treatment of distal radius fracture. Consequences of an uncritical follow-up]. / Konservative Behandlung einer distalen Radiusfraktur : Folgen einer unkritischen Verlaufskontrolle.

A 74-year-old woman sustained a fracture of the distal radius with an additional fracture of the styloid process of the ulna due to a fall. After reduction under local anesthesia immobilization treatment in a forearm cast was initiated. Despite increasing secondary dislocation during radiological x-ray follow-up control, the bone was described as correctly aligned by the treating physician and non-operative treatment was continued. After a total treatment period of 9 months including 7 months of physiotherapy the patient still presented a limited range of motion and local soft tissue swelling of the right wrist. The patient filed a complaint for wrong treatment of the distal radius fracture resulting in severe pain and considerable deformity of the right wrist leading to a significant handicap during activities of daily living. The expert opinion of the arbitration board ascertained a case of medical malpractice in terms of the indications. Due to the initial presence of criteria of radiological instability, an operative treatment had already been indicated at the first presentation. In addition, secondary dislocation during radiological follow-up examination should have led to conversion of treatment in favor of surgery. The arbitration board furthermore concluded that iatrogenic malpractice led to a severe deformity of the right wrist which would result in a loss of grip strength and future arthritic deformation of the wrist. Legal aspects of the case are discussed.

[Foreign body retention after soft tissue laceration. A case of insufficient inspection and documentation]. / Augenbrauenplatzwunde mit übersehenem Fremdkörper. Unzureichende Inspektion und Dokumentation.

A 52-year-old man sustained a laceration to his left eyebrow after a fall in his bathroom. His plastic glasses shattered upon impact. The patient was referred to a local emergency department. After a quick exploration by the physician on call, the wound was closed by a nurse using the Steri-Strip Wound Closure system. No further exploration or imaging was performed. Four weeks after the incident the patient presented to a dermatologist with a "foreign body sensation" at the site of the laceration. Assuming a foreign body granuloma, he was referred to a maxillofacial surgeon who removed plastic debris (parts of the glasses worn by the patient). The wound subsequently healed without further complications.The patient filed a complaint for inadequate treatment in the emergency department. No detailed patient and accident history had been obtained, the wound exploration performed by the physician was superficial, and the wound closure was performed by a nurse. The expert opinion of the arbitration board ascertained a medical malpractice in terms of insufficient history, examination, and a lack of documentation. Specific questioning of the accident history would have led to the suspicion of possible foreign bodies, thus, leading to a more thorough exploration and likely further imaging. The arbitration board concluded that obtaining a detailed accident history and an accurate examination would have revealed the foreign bodies and/or led to further imaging. Complying with this, the patient could have been spared further harm and secondary surgery would have been unnecessary.

[Incomplete paraplegia after delayed diagnostics of motor function deficits. Severe malpractice?]. / Inkomplette Querschnittlähmung nach verzögerter Abklärung motorischer Ausfallserscheinungen. Schwerer Behandlungsfehler?

A 72-year-old female patient was transferred to a rehabilitation centre after surgical stabilization of a subtrochanteric femoral fracture. However, adequate mobilization was not possible there and 5 days after transfer deficits in the motor function of both lower extremities were documented for the first time and an initial paraplegia was diagnosed the following day by a neurologist. Magnetic resonance imaging (MRI) revealed the suspicion of an unstable fracture of the seventh thoracic vertebral body 8 days after the initial symptoms, which was confirmed by computed tomography after another 3 days. Surgical decompression and stabilization were performed at a department for neurosurgery 4 days later but incomplete paraplegia persisted permanently. The patient complained about insufficient diagnostic measures at the rehabilitation centre. The expert opinion concluded that it would have been mandatory to investigate the matter of the newly occurring neurological symptoms immediately but this had only been performed after undue delay, which had to be interpreted as a case of medical malpractice. The expert pointed out that it was not possible to provide clear evidence that emergent diagnosis and surgery would have enabled a significantly better outcome.The arbitration board ascertained a lack of examination and argued that prompt and adequate diagnostic measures would have revealed the relevant pathological finding and thus surgery would have been performed immediately. According to the reversal of evidence in favor of the patient it could be assumed that no permanent neurological damage existed when the first neurological symptoms occurred and that emergent surgery at least had the potential to prevent permanent paraplegia. This opinion of the arbitration board is supported by numerous references in the literature.

[Curriculum "patient safety" for undergraduate medical students at the department of surgery, University of Greifswald]. / Curriculum "Patientensicherheit" im Blockpraktikum Chirurgie an der Universität Greifswald.

BACKGROUND: Risk reducing measures like the surgical checklist have been proven to reduce effectively adverse events and improve patient safety and teamwork among surgical staff members. Nevertheless, many physicians still refuse to use even simple safety tools like the WHO checklist. A progress in patient safety can only be achieved by changing the operating proceedings and mentality of medical students. This is best performed by teaching patient safety already very early in the medical education. METHOD: The present study demonstrates the implementation and evaluation of the curriculum "patient safety" for undergraduate medical students in the 4th year of medical school at the Department of Surgery, University of Greifswald. 141 students evaluated a total of six lectures from April to October 2011. RESULTS: The results indicate that young medical students show great enthusiasm in safety matters and are willing to adopt the principles. Especially the importance of the issue and the didactic design were evaluated as being very high. CONCLUSION: The curriculum "patient safety" as part of the training program in medical school is a powerful and effective educational tool that is able to raise the student's awareness of patient safety affairs. Thereby it is crucial to start early within medical education during the phase of socialisation. We recommend the general implementation of a patient safety curriculum in medical school.

Charging capacitors from thermal fluctuations using diodes.

We theoretically consider a graphene ripple as a Brownian particle coupled to an energy storage circuit. When circuit and particle are at the same temperature, the second law forbids harvesting energy from the thermal motion of the Brownian particle, even if the circuit contains a rectifying diode. However, when the circuit contains a junction followed by two diodes wired in opposition, the approach to equilibrium may become ultraslow. Detailed balance is temporarily broken as current flows between the two diodes and charges storage capacitors. The energy harvested by each capacitor comes from the thermal bath of the diodes while the system obeys the first and second laws of thermodynamics.

Evolution of magnetic surfboards and spin glass behavior in (Fe1-pGap)2TiO5.

The unusual anisotropy of the spin glass (SG) transition in the pseudobrookite system Fe2TiO5has been interpreted as arising from an induced, van der Waals-like, interaction among magnetic clusters. Here we present susceptibility (χ) and specific heat data (C) for Fe2TiO5diluted with non-magnetic Ga, (Fe1-pGap)2TiO5, for disorder parameterp= 0, 0.11, and 0.42, and elastic neutron scattering data forp= 0.20. A uniform suppression ofTgis observed upon increasingp, along with a value ofχTgthat increases asTgdecreases, i.e.dχ(Tg)/dTg<0We also observeCT∝T2in the low temperature limit. The observed behavior places (Fe1-pGap)2TiO5in the category of a strongly geometrically frustrated SG.

[Quality of anesthesiological expert opinion in medical claims cases]. / Qualität anästhesiologischer Gutachten bei medizinischen Schadensfällen.

Expert opinions have an important place for expert testimony in medical disputes. The report should contain a summary about facts and causality between the damage and the medical treatment in question as well as describe the current medical standard. The fulfillment of scientific criteria was investigated in 179 anesthesiological expert opinions from 150 arbitration cases. Anesthesiological expert reports (2005-2007) of the Arbitration Board of the North German Medical Associations were analyzed in terms of structure, general form of assessment and scientific substantiation of statements. Patient damage was confirmed in 76%, treatment failure in 29% and negligent malpractice in 17% of the reports. In 78% of the reports the facts were presented correctly and in 64% the question was answered whether the incident would have occurred even during adequate and professional action. Conclusive statements about the causality between the damage and the medical treatment in question were available only in 60% of the reports. The study findings suggest that anesthesia expert reports present a high incidence of non-scientific claims. The development of guidelines for expert witnesses by the medical societies is urgently recommended.

[Late infections after open reduction and internal fixation of the upper ankle joint]. / Spätinfektion nach Osteosynthese am oberen Sprunggelenk.

A 63-year-old patient suffering from diabetes mellitus and arterial occlusive disease sustained a displaced fracture of the upper ankle joint. The fracture was treated by open reduction and internal fixation (ORIF) but 6 months later a delayed infection developed. Partial implant removal and a single lavage were performed. With persistent signs of infection full implant removal and subsequently debridement and lavage were carried out 3.5 months later followed by arthrodesis of the upper ankle joint. The arbitration board decided that the treatment applied after diagnosing the delayed infection was not sufficient which led to a delay in appropriate treatment. However, whether the arthrodesis of the upper ankle joint could have been prevented could not be proven.

[Infection after anterior cruciate ligament reconstruction: grave error in treatment?]. / Infektion nach arthroskopischer Kreuzbandersatzplastik: schwerer Behandlungsfehler?

A 28-year-old patient showed clear signs of knee joint infection 8 days after arthroscopic reconstruction of the anterior cruciate ligament. The treating physicians recommended further observation although they stated that a knee joint infection could not be reliably excluded. One week later arthroscopic revision was performed and intraoperative smear tests showed infection by Pseudomonas aeruginosa. Therefore, another 6 days later the obviously infected transplant had to be removed. In the long run painful and limited range of motion of the affected knee joint persisted. The patient complained about medical malpractice concerning management of the complication. The expert opinion stated that due to the fateful course of infection the tendon graft could not be retrieved after the eighth day post surgery anyway. Thus, only flawed delay of treatment was criticized. The arbitration board argued, however, that scientific data concerning the fate of infected tendon grafts do not support the expert opinion and that immediate arthroscopy and antibiotic treatment at least had the potential to influence the course of infection in a positive manner. Evidence clearly shows that survival of an infected tendon graft depends on early diagnosis and emergency treatment rather than just on fate. Due to the fact that, although having in mind the possibility of a knee joint infection, the necessary therapy was delayed for 8 days, the arbitration board considered the described medical malpractice a severe treatment error, leading to reversal of evidence in favour of the patient.

Genetic aspects for the behaviour of lactating sows towards humans.

With the keeping of lactating sows in loose housing systems, ensuring work safety for stockpersons is gaining importance. Aim of the present study was to develop tests characterising the behaviour of lactating sows in farrowing environments with more freedom to move. The behaviour towards humans in different management procedures was examined. Emphasis was given to integrate tests into daily routines. The study was conducted in a nucleus herd with 771 purebred Landrace sows. Data were collected from October 2016 until December 2018. Sows were kept in individual indoor pens with movable farrowing crates in which the animals were restrained from 7 days antepartum (ap) to an average of 7 days postpartum (pp). The Dummy Arm Test (DAT; 1444 observations) was used to assess the sows' reaction towards a stockperson handling the piglets around day 4 pp (closed crates). With the Towel Test (TT; 2846 observations), the reaction of sows to a novel object and an unexpected situation was assessed. The Trough Cleaning Test (TCT; 2805 observations) described the sows' response to common procedures such as trough cleaning. TT and TCT were conducted on days 3 pp (closed crates) and 10 pp (open crates). Variance components of behavioural traits were estimated univariately with a linear animal model, and genetic correlations between traits were derived using a multivariate animal model in ASreml 3.0. Most sows showed no or only a slight reaction to human interactions without attempting to attack them. However, a strong defensive reaction of sows was recorded in 4.0% (TCT), 4.5% (TT), and 10.7% (DAT) of observations. This behaviour of sows was observed more frequently in the open than in the closed pen system. Estimates of heritabilities (h2 ± SE) were h2 = 0.17 ± 0.05 for behaviour of sows towards humans (DAT), h2 = 0.19 ± 0.04 for response of sows towards unexpected situations (TT), and h2 = 0.13 ± 0.04 for reactions of animals to TCT. Genetic correlations (rg ± SE) ranged from rg = 0.59 ± 0.37 between TT and TCT to rg = 0.77 ± 0.30 between TT and DAT. Our results show that the developed tests are suitable for assessing the behaviour of sows towards humans. Behavioural traits derived from these tests could be used as new phenotypes for the genetic selection of gentle and easy-to-handle sows. The genetic correlations of all tests studied were positive indicating related reaction patterns.

[Injury to the median nerve after minimally invasive decompression: discrepancy between the surgical report and actual course of surgery]. / Verletzung des N. medianus nach minimal-invasiver Dekompression: Diskrepanz zwischen Operationsbericht und tatsächlichem Operationsablauf.

A 72-year-old man suffering from carpal tunnel syndrome had undergone minimally invasive decompression by using a SafeGuard® Mini-Open Carpal Tunnel Release System. After the operation the patient presented with a paraesthesia in the median nerve distribution. Two months later an operative revision was performed in another hospital. A partial transection of the median nerve and an incomplete release was seen. The surgeon of the first operation stated that detailed informed consent including the risk of iatrogenic nerve injury had been obtained. Furthermore he referred to the operative report, which mentioned the accuracy of the procedure without any problems or complications during surgery. The Arbitration Board stated that the operative report could not exculpate the surgeon because the findings of the operative revision disagreed with the first operative report. The expert opinion declared that the lesion was a result of an inaccurate operative procedure as the surgeon was not able to demonstrate an anatomical variation of the median nerve.

[Wound closure after irrigation with Octenisept® without possibility for drainage]. / Wundverschluss nach Wundspülung mit Octenisept® ohne Abflussmöglichkeit.

A 39-year-old patient suffered a stab wound of the right thenar prominence after an accident with a screwdriver. In the first hospital the deep wound was irrigated with octenidine dihydrochloride/2-phenoxyethanol and closed by suture. During the further course pressure pain and numbness of the right thenar and swelling of the right hand occurred. Three weeks after the accident an operative revision of the wound in a second hospital was performed. The intraoperative findings showed inflammation and necrosis of the right m. abductor pollicis brevis, but no infection with pus.The patient accused the first hospital of irrigating the tissue of his right hand with Octenisept®. The expert option of the Arbitration Board identified improper care in the first hospital with insufficient excision of the wound and incorrect use of the Octenisept® solution. Against the explicit advice of the manufacturing company the wound had been sutured without the possibility of drainage for the Octenisept® solution.

Momentum-space signatures of Berry flux monopoles in the Weyl semimetal TaAs.

Since the early days of Dirac flux quantization, magnetic monopoles have been sought after as a potential corollary of quantized electric charge. As opposed to magnetic monopoles embedded into the theory of electromagnetism, Weyl semimetals (WSM) exhibit Berry flux monopoles in reciprocal parameter space. As a function of crystal momentum, such monopoles locate at the crossing point of spin-polarized bands forming the Weyl cone. Here, we report momentum-resolved spectroscopic signatures of Berry flux monopoles in TaAs as a paradigmatic WSM. We carried out angle-resolved photoelectron spectroscopy at bulk-sensitive soft X-ray energies (SX-ARPES) combined with photoelectron spin detection and circular dichroism. The experiments reveal large spin- and orbital-angular-momentum (SAM and OAM) polarizations of the Weyl-fermion states, resulting from the broken crystalline inversion symmetry in TaAs. Supported by first-principles calculations, our measurements image signatures of a topologically non-trivial winding of the OAM at the Weyl nodes and unveil a chirality-dependent SAM of the Weyl bands. Our results provide directly bulk-sensitive spectroscopic support for the non-trivial band topology in the WSM TaAs, promising to have profound implications for the study of quantum-geometric effects in solids.