Metastability of diamond ramp-compressed to 2 terapascals.

Carbon is the fourth-most prevalent element in the Universe and essential for all known life. In the elemental form it is found in multiple allotropes, including graphite, diamond and fullerenes, and it has long been predicted that even more structures can exist at pressures greater than those at Earth's core1-3. Several phases have been predicted to exist in the multi-terapascal regime, which is important for accurate modelling of the interiors of carbon-rich exoplanets4,5. By compressing solid carbon to 2 terapascals (20 million atmospheres; more than five times the pressure at Earth's core) using ramp-shaped laser pulses and simultaneously measuring nanosecond-duration time-resolved X-ray diffraction, we found that solid carbon retains the diamond structure far beyond its regime of predicted stability. The results confirm predictions that the strength of the tetrahedral molecular orbital bonds in diamond persists under enormous pressure, resulting in large energy barriers that hinder conversion to more-stable high-pressure allotropes1,2, just as graphite formation from metastable diamond is kinetically hindered at atmospheric pressure. This work nearly doubles the highest pressure at which X-ray diffraction has been recorded on any material.

Melting of Tantalum at Multimegabar Pressures on the Nanosecond Timescale.

Tantalum was once thought to be the canonical bcc metal, but is now predicted to transition to the Pnma phase at the high pressures and temperatures expected along the principal Hugoniot. Furthermore, there remains a significant discrepancy between a number of static diamond anvil cell experiments and gas gun experiments in the measured melt temperatures at high pressures. Our in situ x-ray diffraction experiments on shock compressed tantalum show that it does not transition to the Pnma phase or other candidate phases at high pressure. We observe incipient melting at approximately 254±15 GPa and complete melting by 317±10 GPa. These transition pressures from the nanosecond experiments presented here are consistent with what can be inferred from microsecond gas gun sound velocity measurements. Furthermore, the observation of a coexistence region on the Hugoniot implies the lack of significant kinetically controlled deviation from equilibrium behavior. Consequently, we find that kinetics of phase transitions cannot be used to explain the discrepancy between static and dynamic measurements of the tantalum melt curve. Using available high pressure thermodynamic data for tantalum and our measurements of the incipient and complete melting transition pressures, we are able to infer a melting temperature 8070_{-750}^{+1250} K at 254±15 GPa, which is consistent with ambient and a recent static high pressure melt curve measurement.

[Investigation of the reduction in the disability after fractures in children and adolescents]. / Ermittlung der Minderung der Erwerbsfähigkeit nach Frakturen bei Kindern und Jugendlichen.

The student accident insurance has been part of the German Statutory Accident Insurance (Deutsche Gesetzliche Unfallversicherung, DGUV) for 50 years. In order to assess the reduction in working capacity (Minderung der Erwerbsfähigkeit, MdE) in the event of permanent consequences of accidents and injuries, the recommendation to treat the affected child or adolescent "as an average adult" is currently still valid. The present work deals with the everyday practice of the MdE assessment in children and adolescents and their weaknesses through the transfer of the principles from adulthood. In addition, proposals for the adaptation of the assessment principles for the growth age are drawn up.

Probing the Solid Phase of Noble Metal Copper at Terapascal Conditions.

Ramp compression along a low-temperature adiabat offers a unique avenue to explore the physical properties of materials at the highest densities of their solid form, a region inaccessible by single shock compression. Using the National Ignition Facility and OMEGA laser facilities, copper samples were ramp compressed to peak pressures of 2.30 TPa and densities of nearly 30 g/cc, providing fundamental information regarding the compressibility and phase of copper at pressures more than 5 times greater than previously explored. Through x-ray diffraction measurements, we find that the ambient face-centered-cubic structure is preserved up to 1.15 TPa. The ramp compression equation-of-state measurements shows that there are no discontinuities in sound velocities up to 2.30 TPa, suggesting this phase is likely stable up to the peak pressures measured, as predicted by first-principal calculations. The high precision of these quasiabsolute measurements enables us to provide essential benchmarks for advanced computational studies on the behavior of dense monoatomic materials under extreme conditions that constitute a stringent test for solid-state quantum theory. We find that both density-functional theory and the stabilized jellium model, which assumes that the ionic structure can be replaced by an ionic charge distribution by constant positive-charge background, reproduces our data well. Further, our data could serve to establish new international secondary scales of pressure in the terapascal range that is becoming experimentally accessible with advanced static and dynamic compression techniques.

[What to do in cases of postoperative damage of the ulnar nerve after K­wire osteosynthesis of supracondylar humeral fractures in childhood?] / Was tun bei postoperativem Ulnarisschaden nach Kirschner-Draht-Osteosynthese der suprakondylären Humerusfraktur im Kindesalter?

INTRODUCTION: Iatrogenic damage to the ulnar nerve after crossed Kirschner wire osteosynthesis of supracondylar humeral fractures is a preventable complication in pediatric traumatology, which occurs in up to 10% of cases. There are strategies in the literature for avoiding this complication but no consistent suggestions for action in the presence of the damage. METHOD: Within the framework of a questionnaire survey with the support of the German Society for Trauma Surgery, 198 pediatric and trauma surgeons presented their treatment algorithm based on case examples. RESULTS: In preoperatively known accident-related sensorimotor failure, 76.3% perform revision surgery of the nerve as part of primary care. If the treatment-related nerve damage occurs immediately postoperatively, up to 84.3% do this immediately. The rate depends on the extent of nerve damage (sensory vs. sensorimotor) and the reduction method (open vs. closed). The later the nerve damage is diagnosed, the sooner the original course of treatment with timely metal removal is retained or neurophysiological examinations are included. CONCLUSION: Respondents used the clinical extent of the lesion, the timing of the diagnosis and the nature of primary care as criteria for the indications in postoperative ulnar nerve damage. Differences in outcome between invasive and waiting strategies cannot be derived from the study.

Multicentre phase II trial of near-infrared imaging in elective colorectal surgery.

BACKGROUND: Decreasing anastomotic leak rates remain a major goal in colorectal surgery. Assessing intraoperative perfusion by indocyanine green (ICG) with near-infrared (NIR) visualization may assist in selection of intestinal transection level and subsequent anastomotic vascular sufficiency. This study examined the use of NIR-ICG imaging in colorectal surgery. METHODS: This was a prospective phase II study (NCT02459405) of non-selected patients undergoing any elective colorectal operation with anastomosis over a 3-year interval in three tertiary hospitals. A standard protocol was followed to assess NIR-ICG perfusion before and after anastomosis construction in comparison with standard operator visual assessment alone. RESULTS: Five hundred and four patients (median age 64 years, 279 men) having surgery for neoplastic (330) and benign (174) pathology were studied. Some 425 operations (85·3 per cent) were started laparoscopically, with a conversion rate of 5·9 per cent. In all, 220 patients (43·7 per cent) underwent high anterior resection or reversal of Hartmann's operation, and 90 (17·9 per cent) low anterior resection. ICG angiography was achieved in every patient, with a median interval of 29 s to visualization of the signal after injection. NIR-ICG assessment resulted in a change in the site of bowel division in 29 patients (5·8 per cent) with no subsequent leaks in these patients. Leak rates were 2·4 per cent overall (12 of 504), 2·6 per cent for colorectal anastomoses and 3 per cent for low anterior resection. When NIR-ICG imaging was used, the anastomotic leak rates were lower than those in the participating centres from over 1000 similar operations performed with identical technique but without NIR-ICG technology. CONCLUSION: Routine NIR-ICG assessment in patients undergoing elective colorectal surgery is feasible. NIR-ICG use may change intraoperative decisions, which may lead to a reduction in anastomotic leak rates.

Erratum: Measurement of Body-Centered-Cubic Aluminum at 475 GPa [Phys. Rev. Lett. 119, 175702 (2017)].

This corrects the article DOI: 10.1103/PhysRevLett.119.175702.

[Treatment of femoral shaft fractures in children and adolescents ≥50 kg : A retrospective multicenter trial]. / Behandlung der Femurschaftfraktur bei Kindern und Jugendlichen mit einem Körpergewicht ≥50 kg : Eine retrospektive multizentrische Erhebung.

BACKGROUND: Operative treatment of diaphyseal fractures of the femur in older children and adolescents remains controversial due to multiple surgical options and higher complication rates in single-center studies compared to younger children. This retrospective multicenter study aimed to register early and late complications in day-by-day treatment. MATERIAL AND METHODS: Sixteen hospitals with particular expertise in pediatric orthopedic trauma participated in this study. Patients with diaphyseal femur fractures, a body weight ≥50 kg (aged 10-16 years) and treated between 2008 and 2012 were included. Age, weight, fracture type, and choice of operative treatment were correlated to complication rate and type. Patients with pathologic fractures and/or metabolic bone disorders were excluded. RESULTS: Fifty-three children (15 females and 38 males; mean age: 14.2 y [SD 1.4 y]; mean body weight: 60.5 kg [max. 95 kg]) with 54 fractures were included. Elastic stable intramedullary nailing (ESIN) was the treatment of choice in 31 of 42 fractures with open growth plates. In the subgroup with two nails, 7 of 12 patients experienced revision surgery due to instability or shortening. Three patients with ESIN and end caps had no complications. In the subgroup with three inserted nails (11 patients), one patient was converted to external fixation. Nine patients received primary or secondary plate osteosyntheses. Within this group, two patients had deep infections; one implant failure, and one peri-implant fracture were recorded. Adolescent lateral femoral nailing (ALFN), when used as the primary treatment option in two patients, was free of complications. When used as a secondary treatment option in three patients, one patient had a pseudarthrosis and one an infection. Both were treated in further operative procedures. In a group of eight patients with closed physes, regular intramedullary nailing as primary or secondary treatment of choice resulted in one locking screw change. As late complications, leg length discrepancy (LLD) over 15 mm (n = 2) and loss of range of motion (ROM) (n = 4; two knee and three hip) were noted in patients receiving multiple revisions or serious postoperative complication. CONCLUSIONS: Children older than 10 years of age with a body weight ≥50 kg and open physes are prone to complications regardless of treatment choice. A smaller revision rate occurred in patients treated with ESIN and end caps or a third nail compared to the other treatment options. When physes are closed, rigid intramedullary nailing is the treatment of choice.

Measurement of Body-Centered-Cubic Aluminum at 475 GPa.

Nanosecond in situ x-ray diffraction and simultaneous velocimetry measurements were used to determine the crystal structure and pressure, respectively, of ramp-compressed aluminum at stress states between 111 and 475 GPa. The solid-solid Al phase transformations, fcc-hcp and hcp-bcc, are observed at 216±9 and 321±12 GPa, respectively, with the bcc phase persisting to 475 GPa. The high-pressure crystallographic texture of the hcp and bcc phases suggests close-packed or nearly close-packed lattice planes remain parallel through both transformations.

Double-barrelled wet colostomy formation after pelvic exenteration for locally advanced or recurrent rectal cancer.

AIM: In advanced pelvic cancer it may be necessary to perform a total pelvic exenteration. In such cases urinary tract reconstruction is usually achieved with the creation of an ileal conduit with a urinary stoma on the right side of the patient's abdomen and an end colostomy separately on the left. The potential morbidity from a second stoma may be avoided by the use of a double-barrelled wet colostomy (DBWC), as a single stoma. Another advantage is the possibility of using a vertical rectus abdominis muscle flap for perineal reconstruction. METHOD: All patients undergoing formation of a DBWC were included. RESULT: A DBWC was formed in 10 patients. One patient underwent formation of a double-barrelled wet ileostomy. CONCLUSIONS: In this technical note we present our early experience in 11 cases and a video of DBWC formation in a male patient.

X-Ray Diffraction of Solid Tin to 1.2 TPa.

We report direct in situ measurements of the crystal structure of tin between 0.12 and 1.2 TPa, the highest stress at which a crystal structure has ever been observed. Using angle-dispersive powder x-ray diffraction, we find that dynamically compressed Sn transforms to the body-centered-cubic (bcc) structure previously identified by ambient-temperature quasistatic-compression studies and by zero-kelvin density-functional theory predictions between 0.06 and 0.16 TPa. However, we observe no evidence for the hexagonal close-packed (hcp) phase found by those studies to be stable above 0.16 TPa. Instead, our results are consistent with bcc up to 1.2 TPa. We conjecture that at high temperature bcc is stabilized relative to hcp due to differences in vibrational free energy.

Fluorescence angiography in laparoscopic low rectal and anorectal anastomoses with pinpoint perfusion imaging--a critical appraisal with specific focus on leak risk reduction.

BACKGROUND AND AIMS: Anastomotic dehiscence is one of the most feared complications in colorectal surgery leading to significant morbidity and mortality. Progressively lower anastomoses are associated with a greater leak rate. One of the key factors is the perfusion of the bowel to be joined. Presently, surgeons rely on a variety subjective measures to determine anastomotic perfusion and mechanical integrity however these have shortcomings. The aim of this paper is to appraise the literature on the use of fluorescence angiography (FA) in laparoscopic rectal surgery. MATERIALS AND METHODS: A Pubmed search was undertaken using terms 'fluorescence angiography' and 'rectal surgery'. The search was expanded using the related articles function. Studies were included if they used FA specifically for rectal surgery. Outcomes of interest including anastomotic leak rate, change of operative strategy and time taken for FA were recorded. RESULTS: Eleven papers detailing the use of FA in rectal surgery are outlined demonstrating that this technique may change operative strategy and lead to a reduction in anastomotic leak rate. CONCLUSION: In this paper, we discuss assessment of colorectal blood supply using FA and how this technique holds great potential to detect insufficiently perfused bowel. In so doing, the operator can adjust their operative strategy to mitigate these affects with the aim of reducing the complications of anastomotic leak and stenosis. However, it is highlighted that there is a clear need for randomised controlled trials in order to determine this definitively.

Endoscopically assisted extralevator abdominoperineal excision.

AIM: Extralevator abdominoperineal excision (ELAPE) has been advocated to optimize clearance of lower third rectal cancers with an involved or threatened circumferential resection margin. ELAPE could reduce positive margins and specimen perforation compared with standard abdominoperineal excision. However, there can be difficulties with ELAPE, particularly in identifying the anterior plane in male patients. Usually, the dissection is performed in the prone position, which can be hazardous, particularly in obese patients in whom wound problems are commonly encountered. We describe an endoscopically assisted approach for ELAPE in the lithotomy position. METHOD: Three male patients with a rectal tumour located at the anorectal junction underwent an endoscopically assisted ELAPE in the lithotomy position after preoperative radiotherapy. RESULTS: All the procedures were performed successfully with operation times of 180, 390 and 420 mins. There were no instances of intra-operative perforation or other complications. One patient developed postoperative intestinal obstruction which resolved on conservative management. There were no wound complications. Histopathological examination demonstrated clear margins and intact mesorectal planes in each patient. CONCLUSION: We report a good outcome in three patients after endoscopically assisted ELAPE. This approach allows the patient to be operated on in the lithotomy position giving excellent views of the anterior dissection.

[Treatment-related damage to the radial nerve in paediatric traumatology]. / Behandlungsbedingte Schäden des N. radialis in der Kindertraumatologie.

BACKGROUND: Iatrogenic damage of the N. ulnaris is a known complication of treatment of supracondylar humeral fractures in children. But damage to the N. radialis can also occur in the treatment of many typical fractures of the upper extremity during growth. There are no differentiated investigations on their incidence. PATIENTS AND METHODS: This paper presents a prospective case collection and describes the personal experience with the occurrence and treatment of iatrogenic damage to the radial nerve during growth. RESULTS: In all 9 out of 20 cases occurred in the primary care setting, a further 9 under the metal removal and 2 on the occasion of corrective surgery. 50 % occurred after treatment of forearm shaft fractures, 39 % after distal-metaphyseal radius fractures, 11 % after radial neck fractures. In 80 % of the cases the sensory terminal branch was affected, in another 15 % the motor branch and in 5 % the main trunk of the nerve. CONCLUSIONS: The treatment of iatrogenic nerve damage should be cautious and restrained, spontaneous remissions, especially of pure sensory deficits, are common.

Genetic consequences of breaking migratory traditions in barnacle geese Branta leucopsis.

Cultural transmission of migratory traditions enables species to deal with their environment based on experiences from earlier generations. Also, it allows a more adequate and rapid response to rapidly changing environments. When individuals break with their migratory traditions, new population structures can emerge that may affect gene flow. Recently, the migratory traditions of the Barnacle Goose Branta leucopsis changed, and new populations differing in migratory distance emerged. Here, we investigate the population genetic structure of the Barnacle Goose to evaluate the consequences of altered migratory traditions. We used a set of 358 single nucleotide polymorphism (SNP) markers to genotype 418 individuals from breeding populations in Greenland, Spitsbergen, Russia, Sweden and the Netherlands, the latter two being newly emerged populations. We used discriminant analysis of principal components, FST , linkage disequilibrium and a comparison of geneflow models using migrate-n to show that there is significant population structure, but that relatively many pairs of SNPs are in linkage disequilibrium, suggesting recent admixture between these populations. Despite the assumed traditions of migration within populations, we also show that genetic exchange occurs between all populations. The newly established nonmigratory population in the Netherlands is characterized by high emigration into other populations, which suggests more exploratory behaviour, possibly as a result of shortened parental care. These results suggest that migratory traditions in populations are subject to change in geese and that such changes have population genetic consequences. We argue that the emergence of nonmigration probably resulted from developmental plasticity.

[Informed consent consultation as a part of patient safety in pediatric traumatology]. / Das Aufklärungsgespräch als Teil der Patientensicherheit in der Kindertraumatologie.

In pediatric traumatology as in any other surgical specialty, every treatment measure has to be protected by an adequate clarification. A legally effective clarification has to cover various aspects, such as diagnosis, treatment, risk and safety clarification and leads to an informed consent consultation. The contents of this informed consent discussion must be documented. The nature and extent of clarification, among other things depend on the urgency of the procedure and in an emergency it can be dispensed with in pediatric traumatology. In the case of minors the conversation must be conducted basically in the presence of both parents as they alone are legally entitled to give approval. General treatment proxies are not allowed. If it is not possible to talk to both parents the physician is allowed to trust that the parent present represents the will of the absent parent. Intervention cannot be carried out against the will of adolescents capable of self-determination even with the consent of the parents. The application of these rules is illustrated by means of practical examples.

[Fractures of the thoracic and lumbar spine in children and adolescents]. / Frakturen der Brust- und Lendenwirbelsäule im Wachstumsalter.

BACKGROUND: Only 1.5-2% of all fractures in children and adolescents are fractures of the thoracic and lumbar spine. Treatment is most often conservative. This study compares the own experience with the recent literature. MATERIAL AND METHODS: Over a 48 month period all patients with fractures of the thoracic and lumbar spine, younger than 16 years were included prospectively. Of the patients 67 underwent follow-up investigations after 3-36 months. RESULTS: The average age of the patients was 11.9 years. Sports (53%) and traffic (28%) accidents were most frequent. Fractures most often appeared in the mid-thoracic (47%) and thoracolumbar spine (41%). Operative treatment was performed in 9 cases (10.4%). Secondary loss of alignment was not observed neither after conservative nor operative treatment. Neurological deficits (n=2) did not completely improve. CONCLUSIONS: Most fractures of the thoracic and lumbar spine heal fast and without any sequelae. Unstable fractures of type B and C (exclusively occurring as a result of traffic accidents) need operative stabilization as in adults.

Resistance profile and biofilm production of Enterococcus spp., Staphylococcus sp., and Streptococcus spp. from dairy farms in southern Brazil.

Milk is a high nutritional value food that helps in human development and growth. However, it can also harbor microorganisms. Therefore, the objective of this study was to isolate, identify and evaluate the resistance profile and pathogenicity factors of gram-positive cocci isolated from liners in milking rooms in the south of Rio Grande do Sul, Brazil. Biochemical and molecular tests were performed for the identification. The following were isolated: Enterococcus faecalis (10), Enterococcus faecium (4), Staphylococcus intermedius (1), Streptococcus uberis (1), and Streptococcus dysgalactiae (1). The susceptibility of isolated microorganisms to eight antibiotics was evaluated according to CLSI, and the genus that proved to be resistant to most of those was Enterococcus. In addition, all 17 isolates were able to form biofilm, which remained viable after the use of neutral, alkaline and alkaline-chlorinated detergent. The only product that was effective against biofilm of all microorganisms was chlorhexidine 2%. The results obtained highlight the importance of pre- and post-dipping tests on dairy properties, in which chlorhexidine is one of the disinfectants used. As observed, products indicated for cleaning and descaling pipes were not effective on biofilms of the different species tested.

Transition metal phthalocyanines: insight into the electronic structure from soft x-ray spectroscopy.

Transition metal phthalocyanines (MPc's) are an interesting class of material, and their magnetic and electronic properties are determined by the orbital occupation of the transition metal 3d orbitals incorporated in the molecules center. Thus, the ground state configuration of the transition metal center is very important for a complete understanding of these materials. We present experimental data taken using x-ray absorption and x-ray photoemission spectroscopy together with a theoretical interpretation of MPc series with M=Zn, Cu, Ni, Co, Fe, and Mn. The combination of these methods allows us to narrow down possible dominating ground state configurations and shed a brighter light on the electronic structure of these complexes.