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Shared vehicle architectures for fuel cell electric vehicles (FCEVs) and battery electric vehicles (BEVs) allow significant cost reduction in development and production by enabling economies of scale. Therefore, a box-shaped design for a type 4 pressure vessel is developed, which allows an efficient storage of hydrogen in conventional battery design spaces. For a load capable design, the top and bottom of the tank wall are connected with tension struts made of aramid fibers. Based on an analytical design, the geometry of the vessel is defined and a manufacturing process is developed using tufting as key technology for the insertion of the aramid fiber tension struts. The load transfer between the CFRP tank wall and the tension struts is crucial for the mechanical strength of the containment. Fiber loops are evaluated by guiding the tension struts through the CFRP tank wall and deflecting the load. In tensile tests, strengths of at least 1720 MPa are measured for this configuration. The tightness of the containment is ensured by a polymer liner and its adhesion to the struts. The interface between aramid fiber struts and the liner is investigated on strut-level analytically and in experiments. Different shear moduli of the investigated polymers show a major influence on the shear stress in the liner. For the application in the tension-braced pressure vessel, liner materials with the lowest possible modulus should be used to reduce the stress peaks in the liner. Finally, a design corridor for the dimensions of the tension struts and preferred material properties for the liner can be derived. For the investigated material, a strut diameter of 1 mm with a strut spacing of 3 to 5 mm is recommended.

Purpose Surgical treatment of thoracolumbar A3-fractures usually comprises posterior fixation—in neutral position or distraction—potentially followed by subsequent anterior support. We hypothesized that additional posterior compression in circumferential stabilization may increase stability by locking the facets, and better restore the sagittal profile. Methods Burst fractures Type A3 were created in six fresh frozen cadaver spine segments (T12–L2). Testing was performed in a custom-made spinal loading simulator. Loads were applied as pure bending moments of ± 3.75 Nm in all six movement axes. We checked range of motion, neutral zone and Cobb’s angle over the injured/treated segment within the following conditions: Intact, fractured, instrumented in neutral alignment, instrumented in distraction, with cage left in posterior distraction, with cage with posterior compression. Results We found that both types of instrumentation with cage stabilized the segment compared to the fractured state in all motion planes. For flexion/extension and lateral bending, flexibility was decreased even compared to the intact state, however, not in axial rotation, being the most critical movement axis. Additional posterior compression in the presence of a cage significantly decreased flexibility in axial rotation, thus achieving stability comparable to the intact state even in this movement axis. In addition, posterior compression with cage significantly increased lordosis compared to the distracted state. Conclusion Among different surgical modifications tested, circumferential fixation with final posterior compression as the last step resulted in superior stability and improved sagittal alignment. Thus, posterior compression as the last step is recommended in these pathologies.

ZusammenfassungRiesenzelltumore des Knochens gehören zu den Tumoren mit intermediärer Dignität, deren biologisches Verhalten aus dem histologischen Bild nicht sicher prognostiziert werden kann. Häufig zeigen sie ein lokal aggressives, destruierendes Ausbreitungsverhalten und neigen bei unvollständiger Entfernung zu Lokalrezidiven. Auch pulmonale Fernmetastasen kommen vereinzelt vor. Die Diagnostik erfordert bei spinaler Manifestation neben Anamnese, klinischen Befunden und Laborbefunden eine Schnittbildgebung mit CT und MRT, die Sicherung der Diagnose sollte mittels Biopsie erfolgen. Die histologische Beurteilung sollte von Pathologen mit Erfahrung in der Knochentumordiagnostik durchgeführt werden. Aufgrund der Rezidivneigung ist chirurgisch die extraläsionale, weite Exzision des Tumors notwendig, in der Regel mit einer suffizienten Fixation und Fusion. Enge postoperative Verlaufskontrollen sind erforderlich. Neue Aspekte in der begleitenden Therapie ermöglicht der humane monoklonale Antikörper Denosumab.In diesem Artikel zu Riesenzelltumoren der Wirbelsäule berichten wir über Erfahrungen in den letzten 20 Jahren in unserer Klinik, beschreiben 2 Fälle beispielhaft und gehen auf die Diagnostik und neue Aspekte der Therapie mit Denosumab ein.

Purpose To evaluate the AOSpine Thoracolumbar Spine Injury Classification System and if it is reliable and reproducible when applied to the paediatric population globally. Methods A total of 12 paediatric orthopaedic surgeons were asked to review MRI and CT imaging of 25 paediatric patients with thoracolumbar spine traumatic injuries, in order to determine the classification of the lesions observed. The evaluators classified injuries into primary categories: A, B and C. Interobserver reliability was assessed for the initial reading by Fleiss's kappa coefficient (kF) along with 95% confidence intervals (CI). For A and B type injuries, sub-classification was conducted including A0-A4 and B1-B2 subtypes. Interobserver reliability across subclasses was assessed using Krippendorff's alpha (αk) along with bootstrapped 95% CIs. A second round of classification was performed one-month later. Intraobserver reproducibility was assessed for the primary classifications using Fleiss's kappa and sub-classification reproducibility was assessed by Krippendorff's alpha (αk) along with 95% CIs. Results In total, 25 cases were read for a total of 300 initial and 300 repeated evaluations. Adjusted interobserver reliability was almost perfect (kF = 0.74; 95% CI 0.71 to 0.78) across all observers. Sub-classification reliability was substantial (αk= 0.67; 95% CI 0.51 to 0.81), Adjusted intraobserver reproducibility was almost perfect (kF = 0.91; 95% CI 0.83 to 0.99) for both primary classifications and for sub-classifications (αk = 0.88; 95% CI 0.83 to 0.93). Conclusion The inter- and intraobserver reliability for the AOSpine Thoracolumbar Spine Injury Classification System was high amongst paediatric orthopaedic surgeons. The AOSpine Thoracolumbar Spine Injury Classification System is a promising option as a uniform fracture classification in children. Level of Evidence III

The morphology of the rib cage affects both the biomechanics of the upper body's musculoskeletal structure and the respiratory mechanics. This becomes particularly important when evaluating skeletal deformities, as in adolescent idiopathic scoliosis (AIS). The aim of this study was to identify morphological characteristics of the rib cage in relation to the lung in patients with non‐deformed and scoliotic spines. Computed tomography data of 40 patients without any visible spinal abnormalities (healthy group) and 21 patients with AIS were obtained retrospectively. All bony structures as well as the right and left lung were reconstructed using image segmentation. Morphological parameters were calculated based on the distances between characteristic morphological landmarks. These parameters included the rib position, length, and area, the rib cage depth and width, and the rib inclination angle on either side, as well as the spinal height and length. Furthermore, we determined the left and right lung volumes, and the area of contact between the rib cage and lung. Differences between healthy and scoliotic spines were statistically analysed using the t‐test for unpaired data. The rib cage of the AIS group was significantly deformed in the dorso‐ventral and medio‐lateral directions. The anatomical proximity of the lung to the ribs was nearly symmetrical in the healthy group. By contrast, within the AIS group, the lung covered a significantly greater area on the left side of the rib cage at large thoracic deformities. Within the levels T1–T6, no significant difference in the rib length, depth to width relationship, or area was observed between the healthy and AIS groups. Inferior to the lung (T7–T12), these parameters exhibited greater variability. The ratio between the width of the rib cage at T6 and the thoracic spinal height (T1–T12) was significantly increased within the thoracic AIS group (1.1 ± 0.08) compared with the healthy group (1.0 ± 0.05). No statistical differences were found between the lung volumes among all the groups. While the rib cage was frequently strongly deformed in the AIS group, the lung and its surrounding ribs appeared to be normally developed. The observed rib hump in AIS appeared to be formed particularly by a more ventral position of the ribs on the concave side. Furthermore, the rib cage width to spinal height ratio suggested that the spinal height of the thoracic AIS‐spine is reduced. This indicates that the spine would gain its growth‐related height after correcting the spinal deformity. These are the important aspects to consider in the aetiology research and orthopaedic treatment of AIS.

Neuromuskulare Skoliosen (NMS) sind Skoliosen, die auf einer Storung des neuromuskularen Systems beruhen. Diese fuhrt zu einer fruh einsetzenden Deformitat mit rascher Progredienz. Konservative Therapien haben hier einen geringen Stellenwert, Korsette konnen im Wachstumsalter eingesetzt werden. Die Ziele der meist dorsalen Wirbelsaulenoperationen sind die Korrektur der Deformitat und die Verhinderung der Progression. In diesem Artikel gehen wir auf die Besonderheiten bei der Versorgung von Kindern mit NMS ein und beleuchten auch neuere Therapieverfahren fur sehr junge Kinder. Typische Falle werden detailliert beschrieben.

Echinokokkosen beim Menschen sind selten, ein Knochenbefall ist mit weniger als 1 % sehr selten, ein primar spinaler Befall durch Echinokokken gilt als Raritat. Wir berichten uber den lumbalen und sakralen Befall durch Echinococcus multilocularis bei einem 56-jahrigen mannlichen Kaukasier mit sensiblen neurologischen Ausfallen und im Vordergrund stehenden tief lumbalen Ruckenschmerzen. Bei Verdacht auf Spondylodiszitis als Arbeitshypothese erfolgten computertomographiegesteuerte Biopsien, die ohne Ergebnis blieben, sodass eine chirurgische Probenentnahme erfolgte. Die Diagnose des spinalen Echinokokkenbefalls konnte gestellt werden. Es wurde ein radikales chirurgisches Debridement durchgefuhrt und eine antihelminthische Therapie begonnen. Im vorliegenden Beitrag beschreiben wir diesen ungewohnlichen Fall im Detail und geben eine kurze Ubersicht uber die aktuelle Literatur zu dieser Erkrankung.

Quasiracemates – materials consisting of pairs of near enantiomers – form crystalline motifs that mimic the inversion relationships observed for their racemic counterparts. Recent investigations from our group explored a family of chiral (N-benzoyl)methylbenzylamines to understand the structural boundary of cocrystallization. This investigation extends these earlier studies to include naphthylamide quasiracemates, where the molecular framework is ∼20% larger by volume than the previous diarylamides. A family of naphthylamides was prepared where the pendant functional group differs incrementally in size (i.e., H to C6H5) to give 55 possible unique pairs of racemic and quasiracemic combinations. Data collected from these materials using X-ray crystallography, thermal analysis methods and lattice energy calculations offer important insight into how a spatially larger naphthylamide molecular framework promotes greater structural variance of substituents during the pairwise assembly of quasienantiomers.

We use N = 8 supergravity as a toy model for understanding the dynamics of black hole binary systems via the scattering amplitudes approach. We compute the conservative part of the classical scattering angle of two extremal (half-BPS) black holes with minimal charge misalignment at O(G3) using the eikonal approximation and effective field theory, finding agreement between both methods. We construct the massive loop integrands by Kaluza-Klein reduction of the known D-dimensional massless integrands. To carry out integration we formulate a novel method for calculating the post-Minkowskian expansion with exact velocity dependence, by solving velocity differential equations for the Feynman integrals subject to modified boundary conditions that isolate conservative contributions from the potential region. Motivated by a recent result for universality in massless scattering, we compare the scattering angle to the result found by Bern et. al. in Einstein gravity and find that they coincide in the high-energy limit, suggesting graviton dominance at this order. © 2020, The Author(s)., Journal of High Energy Physics, 2020 (11), ISSN:1126-6708, ISSN:1029-8479

Purpose The atlantoaxial joint represents the most mobile joint complex within the spine, secured by ligaments and capsules. Integrity of the atlantoaxial joint is crucial with respect to the mobility of the head and the upper spine. Atlantoaxial rotatory dislocation is the most common type of injury within this joint in children and is characterized by a typical position of the head (cock robin position). Nevertheless, this type of injury is frequently overlooked. The purpose of the current study was threefold. First, the characteristics of the patients with atlantoaxial dislocation were identified. Next, we checked if the time to treatment did influence the type of treatment. Finally, we checked if the age of the child at the time of treatment influenced the type of treatment. Methods Forty-four children, who were treated consecutively due to atlantoaxial dislocation at a single spine center between September 1993 and October 2018, are analyzed retrospectively regarding age, sex, symptoms, etiology, time to diagnosis, time to treatment, and outcome. Results Forty-four children (30 girls, mean age 8.9 years) were included in the study. The cock robin head position was found in all of them, but neurological deficits were not found in any of them. In 21 patients, dislocation was caused by previous infection (Grisel's syndrome), whereas in 19 patients, dislocation was due to minor trauma. In 4 cases, etiology remained unknown. Mean time to sufficient treatment was 178 days. Eighteen patients received closed reduction and immobilization after 57 days at mean. Open reduction followed by temporary fixation was done in 12 patients after a mean time gap of 188 days. Bony atlantoaxial fusion was necessary in 14 children, who were diagnosed after 319 days on average. Invasiveness of treatment was dependent on the time delay between development of dislocation and treatment; a significant difference was found between invasiveness of treatment and time to treatment (Kruskal–Wallis test, p Conclusion Young girls are predisposed to incur an atlantoaxial rotatory dislocation, which usually occurs due to minor trauma or infection. The cock robin position is characteristic, but neurological deficits are not common. There is a need for early and sufficient treatment because delayed treatment necessitates more invasive treatment, thus leading to a complete loss of function of the most mobile joint within the spine. Finally, older children are predisposed to more invasive treatment strategies.

Purpose The complement system is a crucial part of innate immunity. Recent work demonstrated an unexpected contribution to tissue homeostasis and degeneration. This study investigated for the first time, in human disc tissues, the deposition profile of the complement activation product terminal complement complex (TCC), an inflammatory trigger and inducer of cell lysis, and its inhibitor CD59, and their correlation with the degree of disc degeneration (DD). Methods Disc biopsies were collected from patients diagnosed with DD (n = 39, age 63 ± 12) and adolescent idiopathic scoliosis (AIS, n = 10, age 17 ± 4) and compared with discs from healthy Young (n = 11, age 7 ± 7) and Elder (n = 10, age 65 ± 15) donors. Immunohistochemical detection of TCC and CD59 in nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) was correlated with age, Pfirrmann grade and Modic changes. Results Higher percentage of TCC+ cells was detected in the NP and EP of DD compared to Elder (P P P Conclusion TCC deposition positively correlated with the degree of disc degeneration. A functional relevance of TCC may exist in DD, representing a potential target for new therapeutics.

Magnetically controlled growing rods (MCGR) for the surgical treatment of early onset scoliosis (EOS) allow non-invasive outpatient based distractions during spinal growth. The purpose of this study is to present the results of a single center case series of 22 patients, evaluate the effect of MCGR treatment on the development of spino-pelvic parameters during growth, and report initial outcomes after end of treatment.Prospectively collected data of 22 EOS patients with MCGR treatment has been analyzed. The following radiological parameters were measured before index surgery, after index surgery, 1 year after index surgery, and at last follow-up: Cobb angle of the major curves, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Mean age at index surgery was 9.5 years (range: 4-14 years). Mean length of follow-up was 47.6 months (range: 25-121 months). Etiology of diagnosis was idiopathic in 14 patients, associated with neurofibromatosis in 2 patients, and neuromuscular or syndromic in 6 patients.Mean Cobb angle of the major curve was 57° preoperatively and 29° at last follow-up (p 0.0005). Mean TK was 20.1° preoperatively and 20° at last follow-up (p 0.05). Mean LL was 52.8° preoperatively and 53.2° at last follow-up (p 0.05). Mean PI was 43.2° preoperatively and 46.3° at last follow-up (p 0.05). Mean PT was 4.1° preoperatively and 5.8° at last follow-up (p 0.05). Mean SS was 39.2° preoperatively and 41.7° at last follow-up (p 0.05). 14 patients finished treatment: nine received final fusion and five received rod removal without fusion. Twelve complications occurred: one deep wound infection, six patients developed proximal junctional kyphosis (PJK), one rod fracture, two rods failed to distract, one deformity progressed after rod removal and required spinal fusion, and one patient developed autofusion of the spine prior to end of treatment.MCGR treatment is able to control deformity progression. Complication rate was 54.5%. Sagittal balance was not altered and treatment does not seem to have a negative impact on the development of spino-pelvic parameters during growth. Optimal end of treatment for the individual patient still has to be defined.

Wirbelsaulenverletzungen im Kindesalter sind insgesamt sehr selten. Aktuelle einschlagige Studien mit grosen Fallzahlen, aus welchen sich evidenzbasierte Empfehlungen zu Diagnostik und Therapie von Wirbelsaulenverletzungen bei padiatrischen Patienten ableiten lassen, existieren nicht. Formulierung von Empfehlungen zu Diagnostik und Therapie von Verletzungen der Brust- und Lendenwirbelsaule im Kindesalter. Zunachst erfolgte eine Recherche von Primar-, aber auch Sekundarliteratur zum Themenkomplex Diagnostik und Therapie von Verletzungen der Wirbelsaule bei Kindern. Eine entsprechende interne Literaturdatenbank wurde angelegt und gepflegt. Im Zeitraum von April 2017 bis Dezember 2019 fanden sich die Mitglieder der Arbeitsgemeinschaft Wirbelsaulentrauma im Kindesalter der Sektion Wirbelsaule der Deutschen Gesellschaft fur Orthopadie und Unfallchirurgie zu einem Konsensusprozess zusammen. In 9 Arbeitstreffen wurden systematisch Empfehlungen zu Diagnostik und Therapie von Verletzungen der Wirbelsaule bei Kindern formuliert. Es konnten Empfehlungen zu Diagnostik und Therapie von Verletzungen der Brust- und Lendenwirbelsaule fur 3 Altersstufen (Altersstufe I: 0 bis 6 Jahre; Altersstufe II: 7 bis 9 Jahre; Altersstufe III: 10 bi s16 Jahre) formuliert werden. Die Prinzipien der Diagnostik und Therapie aus der Erwachsenenmedizin konnen nicht problemlos ubertragen werden. Wirbelsaulenverletzungen im Kindesalter sind selten und sollten der Behandlung in geeigneten Zentren zugefuhrt werden. Die MRT-Diagnostik sollte beim kardiopulmonal stabilen Kind mit Verdacht auf ein Monotrauma der Wirbelsaule als initiale Bildgebung indiziert werden. Die grundlegenden Therapieziele bei Verletzungen der Brust- und Lendenwirbelsaule im Kindesalter sind die Wiederherstellung der Stabilitat, der Schutz der neurogenen Strukturen und das Wiederherstellen der anatomisch korrekten Verhaltnisse. Bei der Indikationsstellung zur konservativen vs. operativen Therapie mussen das Korrektur- und Regenerationspotenzial der einzelnen Wirbelsaulenabschnitte in Abhangigkeit vom Patientenalter berucksichtigt werden. Die operative Stabilisierung soll v. a. uber minimalinvasive Techniken, im Sinne einer Instrumentierung ohne Spondylodese und fruhzeitiger Metallentfernung, erfolgen.

Generell stellen Wirbelsaulenverletzungen bei Kindern im Alter unter 16 Jahren eine seltene Verletzungsentitat dar. Fur Deutschland liegen keine belastbaren Daten bezuglich der Epidemiologie von Verletzungen der Wirbelsaule im Kindesalter vor. Gerade bei padiatrischen Patienten, bei denen sowohl die Anamnese, die klinische Untersuchung, aber auch die Durchfuhrung der bildgebenden Diagnostik haufig erschwert sind, mussen samtliche Hinweise auf eine Verletzung der Wirbelsaule mitberucksichtigt werden. Das Ziel der vorliegenden Studie war die Bereitstellung epidemiologischer Daten von padiatrischen Patienten mit Wirbelsaulenverletzungen in Deutschland, um diese zukunftig in die Entscheidungsfindung bei der Diagnostik und Therapie dieser Patienten einfliesen lassen zu konnen. Im Rahmen einer nationalen Multizenterstudie wurden retrospektiv Patientendaten innerhalb eines Zeitraums von 7 Jahren aus 6 Wirbelsaulenzentren erhoben. Neben den demografischen Daten wurden der Unfallmechanismus, die betroffene Wirbelsaulenregion und auch die Begleitverletzungen erhoben. Zudem erfolgte die Erfassung der bildgebenden Diagnostik sowie der jeweiligen Therapie. Es konnten 367 Kinder (weiblich: mannlich = 1:1,2) mit insgesamt 610 Verletzungen an der Wirbelsaule in die Studie eingeschlossen werden. Das mittlere Alter betrug 12 (±3,5) Jahre. Die haufigsten Unfallmechanismen in allen Altersgruppen waren ein Sturz aus unter 3 m Hohe sowie Verkehrsunfalle. Die bildgebende Diagnostik musste nur in Ausnahmefallen in Narkose durchgefuhrt werden. Wahrend jungere Kinder (0 bis 9 Jahre) eher Verletzungen im Bereich der Halswirbelsaule erlitten, zeigten sich Verletzungen der thorakolumbalen Wirbelsaule eher bei Kindern >10 Jahren. Die Kinder wiesen haufige Begleitverletzungen an Kopf und Extremitaten auf. Im Bereich der Wirbelsaule befanden sich weitere Verletzungen meist benachbart und nur selten in anderen Regionen. Rund 75 % der Kinder wurden konservativ behandelt. Die Ergebnisse unterscheiden sich von den Erkenntnissen aus der Erwachsenenmedizin und beschreiben spezielle Gegebenheiten fur padiatrische Patienten mit Wirbelsaulenverletzungen. Trotz gewisser Limitationen konnen sie so bei der Entscheidungsfindung uber die durchzufuhrende Diagnostik und Therapie dieser Patienten helfen.

We compute classical gravitational observables for the scattering of two spinless black holes in general relativity and $\mathcal N {=} 8$ supergravity in the formalism of Kosower, Maybee, and O'Connell (KMOC). We focus on the gravitational impulse with radiation reaction and the radiated momentum in black hole scattering at $\mathcal O(G^3)$ to all orders in the velocity. These classical observables require the construction and evaluation of certain loop-level quantities which are greatly simplified by harnessing recent advances from scattering amplitudes and collider physics. In particular, we make use of generalized unitarity to construct the relevant loop integrands, employ reverse unitarity, the method of regions, integration-by-parts (IBP), and (canonical) differential equations to simplify and evaluate all loop and phase-space integrals to obtain the classical gravitational observables of interest to two-loop order. The KMOC formalism naturally incorporates radiation effects which enables us to explore these classical quantities beyond the conservative two-body dynamics. From the impulse and the radiated momentum, we extract the scattering angle and the radiated energy. Finally, we discuss universality of the impulse in the high-energy limit and the relation to the eikonal phase., 69 pages, 11 figures

Background Atlantoaxial fixation is technically challenging in younger children. The C1-C2 screw-rod fixation technique is established for adults but limited data about the clinical and radiographical outcome for the treatment of children with 5 years of age or younger is available. Methods All files of children who were consecutively treated for spinal disorders were reviewed. Inclusion criteria for further evaluation were: 0 to 5 years of age at initial procedure; detailed surgical report of a posterior C1-C2 fusion with mass lateral and pedicle screw-rod fixation as described by Harms; a minimum clinical and radiographical follow-up of 24 months. The postoperative and last follow-up computed tomography scan and radiographs were used to assess the positioning and stability of the C1-C2 screw-rod construct. Results Eleven patients (3 boys) with a mean age of 46 months (range: 8 to 66 mo) fulfilled inclusion criteria and were evaluated retrospectively. The mean clinical and radiographical follow-up was 79 months (range: 24 mo to 170 mo). The diagnosis was atlantoaxial rotatory dislocation (4 cases), C1-C2 instability with subluxation (3 cases), atlantoaxial dislocation and os odontoideum (1 case), type II odontoid fracture (1 case), traumatic odontoid epiphysiolysis (1 case), and traumatic rupture of the transverse ligament with C1 subluxation (1 case). Intraoperatively and postoperatively no new neurovascular or vascular complication occurred. C1 lateral mass screws were placed correctly in all cases. Twenty-two C2 pedicle screws were placed correctly (85.7%), and 3 screws showed penetration of the pedicle wall (14.3%). No implant revision, implant failure, and pseudarthrosis were noted. Loss of correction was noted in 1 patient with unilateral C1-C2 fixation and a repeated dorsal fusion procedures were performed. A repeat procedure for implant removal and segmental release was performed in 3 patients to increase the axial rotation of the head. Conclusions The C1-C2 screw-rod fixation is a safe technique that achieves solid fixation of the atlantoaxial complex in young children with various disorders. The technique preserves the joint and allows for segmental release via implant removal.

We present the case of a postoperative intracranial hypotension due to a misplaced intrathecal screw. Although typical symptoms such as orthostatic headache were present immediately after surgery, diagnosis was hidden until 20 years later, resulting in a disastrous clinical course.

A new aspherical scattering factor formalism was implemented in SHELXL. It relies on Gaussian functions and can optionally complement the independent atom model to take into account the deformation of electron-density distribution due to chemical bonding and lone pairs. The automated atom-type assignment was derived from the invariom formalism., A new aspherical scattering factor formalism has been implemented in the crystallographic least-squares refinement program SHELXL. The formalism relies on Gaussian functions and can optionally complement the independent atom model to take into account the deformation of electron-density distribution due to chemical bonding and lone pairs. Asphericity contributions were derived from the electron density obtained from quantum-chemical density functional theory computations of suitable model compounds that contain particular chemical environments, as defined by the invariom formalism. Thanks to a new algorithm, invariom assignment for refinement in SHELXL is automated. A suitable parameterization for each chemical environment within the new model was achieved by metaheuristics. Figures of merit, precision and accuracy of crystallographic least-squares refinements improve significantly upon using the new model.

The simple system of tetraammonium octafluorouranate is employed to derive a fundamental understanding of the uranium–fluorine interaction. The structure is composed of isolated molecules, enabling a detailed examination of the U4+ (f2) ion. Characterization of single-crystals by X-ray diffraction, absorption spectroscopy, and magnetic analysis up to 45 T is combined with extensive theoretical treatment by CASSCF. The influence of different active spaces and representations of the structure is examined in the context of the experimental evidence. The Interacting Quantum Atoms method (IQA) is used to examine the nature of the U–F bond, concluding that there is a non-negligible degree of covalent character (9% of the total bond energy) in [UF8]4−. For the structural and theoretical reasons discussed herein, it is proposed that the structure of (NH4)4UF8 may be appropriately employed as a benchmark compound for future theoretical characterization of U(IV).

We compute the total radiated momentum carried by gravitational waves during the scattering of two spinless black holes at the lowest order in Newton's constant, $\mathcal O(G^3)$, and all orders in velocity. By analytic continuation into the bound state regime, we obtain the ${\cal O}(G^3)$ energy loss in elliptic orbits. This provides an essential step towards the complete understanding of the third-post-Minkowskian binary dynamics. We employ the formalism of Kosower, Maybee, and O'Connell (KMOC) which relates classical observables to quantum scattering amplitudes and derive the relevant integrands using generalized unitarity. The subsequent phase-space integrations are performed via the reverse unitarity method familiar from collider physics, using differential equations to obtain the exact velocity dependence from near-static boundary conditions., 5 pages + references, 3 figures. v2: published version

Purpose Formation of terminal complement complex (TCC), a downstream complement system activation product inducing inflammatory processes and cell lysis, has been identified in degenerated discs. However, it remains unclear which molecular factors regulate complement activation during disc degeneration (DD). This study investigated a possible involvement of the pro-inflammatory cytokine interleukin-1β (IL-1β) and the lysosomal protease cathepsin D (CTSD). Methods Disc biopsies were collected from patients suffering from DD (n = 43) and adolescent idiopathic scoliosis (AIS, n = 13). Standardized tissue punches and isolated cells from nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) were stimulated with 5% human serum (HS) alone or in combination with IL-1β, CTSD or zymosan. TCC formation and modulation by the complement regulatory proteins CD46, CD55 and CD59 were analysed. Results In DD tissue cultures, IL-1β stimulation decreased the percentage of TCC + cells in AF and EP (P P P P Conclusion These results suggest a functional relevance of IL-1β and CTSD in modulating TCC formation in DD, with differences between tissue regions. Although strong TCC deposition may represent a degeneration-associated event, IL-1β may inhibit it. In contrast, TCC formation was shown to be triggered by CTSD, indicating a multifunctional involvement in disc pathophysiology.

We present the first public version of Caravel, a C++17 framework for the computation of multi-loop scattering amplitudes in quantum field theory, based on the numerical unitarity method. Caravel is composed of modules for the D-dimensional decomposition of integrands of scattering amplitudes into master and surface terms, the computation of tree-level amplitudes in floating point or finite-field arithmetic, the numerical computation of one- and two-loop amplitudes in QCD and Einstein gravity, and functional reconstruction tools. We provide programs that showcase Caravel’s main functionalities and allow to compute selected one- and two-loop amplitudes. We present the first public version of Caravel, a C++17 framework for the computation of multi-loop scattering amplitudes in quantum field theory, based on the numerical unitarity method. Caravel is composed of modules for the $D$-dimensional decomposition of integrands of scattering amplitudes into master and surface terms, the computation of tree-level amplitudes in floating point or finite-field arithmetic, the numerical computation of one- and two-loop amplitudes in QCD and Einstein gravity, and functional reconstruction tools. We provide programs that showcase Caravel's main functionalities and allow to compute selected one- and two-loop amplitudes.

Spinal alignment changes with age and degeneration. Different compensatory mechanisms of the spine are necessary to preserve spinal balance. The capacity of compensation of the spine decreases with age. Thus, the pelvis and the lower limbs become involved in the compensatory mechanism. Concomitant osteoarthritis of the hip could impair this capacity. The biomechanical principles of compensation are described with respect to planning reconstructive hip and spine surgery.

We demonstrate the universality of the gravitational classical deflection angle of massless particles through O(G^3) by studying the high-energy limit of full two-loop four-graviton scattering amplitudes in pure Einstein gravity as well as N >= 4 supergravity. As a by-product, our first-principles calculation provides a direct confirmation of the massless deflection angle in Einstein gravity proposed long ago by Amati, Ciafaloni and Veneziano, and is inconsistent with a recently proposed alternative., 5 pages, 1 figure

The complement system is a crucial part of innate immunity. Recent work demonstrated an unexpected contribution to tissue homeostasis and degeneration. This study investigated for the first time, in human disc tissues, the deposition profile of the complement activation product terminal complement complex (TCC), an inflammatory trigger and inducer of cell lysis, and its inhibitor CD59, and their correlation with the degree of disc degeneration (DD).Disc biopsies were collected from patients diagnosed with DD (n = 39, age 63 ± 12) and adolescent idiopathic scoliosis (AIS, n = 10, age 17 ± 4) and compared with discs from healthy Young (n = 11, age 7 ± 7) and Elder (n = 10, age 65 ± 15) donors. Immunohistochemical detection of TCC and CD59 in nucleus pulposus (NP), annulus fibrosus (AF) and endplate (EP) was correlated with age, Pfirrmann grade and Modic changes.Higher percentage of TCC+ cells was detected in the NP and EP of DD compared to Elder (P 0.05), and in the EP of Young versus Elder (P 0.001). In DD, TCC deposition was positively correlated with Pfirrmann grade, but not with Modic changes, whereas for Young donors, a negative correlation was found with age, indicating TCC's involvement not only in DD, but also in early stages of skeletal development. Higher CD59 positivity was found in AIS and DD groups compared to Young (P 0.05), and it was negatively correlated with the age of the patients.TCC deposition positively correlated with the degree of disc degeneration. A functional relevance of TCC may exist in DD, representing a potential target for new therapeutics.

Spinal injuries in pediatric patients are overall very rare. Current reference studies including large patient numbers that enable the formulation of evidence-based recommendations on diagnostics and treatment of these injuries do not exist.The aim of the current study was to formulate recommendations on the diagnostics and treatment for injuries of the thoracic and lumbar spine in pediatric patients.Firstly, a search for primary and secondary literature on the topic of diagnostics and treatment of spinal injuries in children was carried out. From this, a literature database was established and maintained. Secondly, within the framework of 9 meetings in the time period from April 2017 to December 2019 the members of the Pediatric Spinal Trauma Group of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU) documented recommendations on diagnostics and treatment of injuries of the thoracic and lumbar spine in pediatric patients by a consensus process.Recommendations on the diagnostics and treatment of injuries of the thoracic and lumbar spine could be given for 3 age groups (age group I: 0-6 years; age group II: 7-9 years; age group III: 10-16 years). Diagnostic and therapeutic principles known from adult patients suffering from injuries to the thoracic or lumbar spine cannot easily be transferred to pediatric patients.Spinal injuries in childhood are rare and should be treated in specialized spine centers. Pediatric patients with a stable cardiopulmonary status should undergo magnetic resonance imaging (MRI) if a spinal trauma is suspected. The basic principles of the treatment of spinal trauma in children is the restoration of spinal stability and correct anatomical parameters as well as the protection of all neural structures. The potential for correction and regeneration of the individual spinal sections depending on the age of the patient must be considered for deciding between operative vs. conservative treatment. Whenever operative treatment is needed, it should be performed by minimally invasive techniques as a sole instrumentation without spondylodesis. An early removal of the screw-rod-system should be performed.

In general, pediatric spinal injuries are rare. No reliable data on the epidemiology of spinal injuries in pediatric patients in Germany are available. Especially in pediatric patients, for whom the medical history, clinical examination and the performance of imaging diagnostics are difficult to obtain, all available information on a spinal injury must be taken into account.The aim of this study was to provide epidemiological data for pediatric patients with spinal trauma in Germany in order to enhance future decision-making for the diagnostics and treatment of these patients.Within the framework of a national multicenter study, data were retrospectively obtained from 6 German spine centers for 7 years between January 2010 and December 2016. In addition to the demographic data, the clinical databases were screened for specific trauma mechanisms, level of injury as well as accompanying injuries. Furthermore, diagnostic imaging and the treatment selected were also analyzed.A total of 367 children (female: male = 1:1.2) with a total of 610 spinal injuries were included in this study. The mean age was 12 years (±3.5 years). The most frequent trauma mechanisms were falls from3 m and traffic accidents. The imaging diagnostics were only rarely carried out with the child under anesthesia. Younger children (0-9 years old) suffered more injuries to the cervical spine, whereas injuries to the thoracic and lumbar spine were more frequently found in older children (10 years old). The children frequently showed accompanying injuries to the head and the extremities. Accompanying spinal injuries mostly occurred in adjacent regions and only rarely in other regions. Around 75% of the children were treated conservatively.The results were different from the knowledge obtained from adult patients with spinal trauma and describe the special circumstances for pediatric patients with spinal trauma. Despite certain limitations these facts may help to enhance future decision-making for the diagnostics and treatment of these patients.

Severe cervical spine injuries in children under the age of 17 years are rare. Recommendations or even guidelines for the diagnostics and treatment of such injuries in children are currently not available.The aim of the study was to formulate recommendations for diagnostics and treatment of injuries of the cervical spine in pediatric patients.First, a search of primary and secondary literature on the topic complex of diagnostics and treatment of cervical spine injuries in children was carried out. An appropriate internal literature database was defined and maintained. Second, within the framework of 9 meetings from April 2017 to December 2019 the members of the Pediatric Spinal Trauma Group of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU) systematically formulated recommendations for the diagnostics and treatment of injuries of the cervical spine in pediatric patients by a consensus process.Recommendation for the diagnostics and treatment for injuries of the cervical spine could be formulated for three age groups (age group I: 0-6 years; age group II: 7-9 years; age group III: 10-16 years). The diagnostic and therapeutic principles known from adult patients suffering from injuries to the cervical spine cannot be easily transferred to pediatric patients.Injuries to the pediatric spine are rare and should be treated in specialized spine centers. Pediatric patients with a stable cardiopulmonary status should undergo magnetic resonance imaging (MRI) if a spinal trauma is suspected. Classification systems and therapeutic recommendations for injuries to the cervical spine known from adult patients could also be used for adolescent patients. This is not possible for children under the age of 10 years. Only few classification systems exist for this age group. Basic principles of the treatment of spinal trauma in children is the restoration of spinal stability and correct anatomical relationships as well as the protection of all neural structures.

We present the analytic form of the two-loop four-graviton scattering amplitudes in Einstein gravity. To remove ultraviolet divergences we include counterterms quadratic and cubic in the Riemann curvature tensor. The two-loop numerical unitarity approach is used to deal with the challenging momentum dependence of the interactions. We exploit the algebraic properties of the integrand of the amplitude in order to map it to a minimal basis of Feynman integrals. Analytic expressions are obtained from numerical evaluations of the amplitude. Finally, we show that four-graviton scattering observables depend on fewer couplings than naively expected., Comment: 5 pages, 1 figure

BACKGROUND Congenital scoliosis due to hemivertebra of the cervicodorsal spine is a rare disorder. It might be accompanied by impaired cosmetic appearances such as head tilt and trunk shift. Little is known about the effect of correction of the major curve on head tilt and trunk shift in children. The purpose of this study was to assess radiographic changes of head tilt and trunk shift following posterior hemivertebra resection (PHVR). METHODS Retrospectively, all children who underwent PHVR at the cervicodorsal spine (C6-Th6) with pedicle screw fixation with a minimum radiographic follow-up of 1 year were identified for further assessment. A total of 5 radiographic parameters were assessed on preoperative, postoperative, and final follow-up radiographs. (1) Head tilt was defined as the angle between the horizontal line and the line through both molars of the maxillary, (2) trunk shift as the angle between the line of the center of C7 to the sacrum and the central sacral vertical line, (3) Cobb angle was used to assess the major curve, (4) cranial, and (5) caudal compensatory curvature. RESULTS Seven boys and 10 girls with a mean age of 9.0 years at surgery were evaluated. The mean radiographic follow-up was 89.5 months (range: 12 to 166 mo). The mean head tilt reoriented from 6.9 to 1.9 degrees (P

Cross-sectional study.To assess the inter- and intraobserver reliability of thoracic, spino-pelvic, and rod lengthening measurements made on biplanar spinal stereoradiography (EOS imaging) in children treated with magnetically controlled growing rod (MCGR).MCGR treatment aims to gain spine length while gradually correcting the spinal deformity. Monitoring thoracic and spino-pelvic parameters is crucial for successful management. EOS imaging is widely used for diagnosis and monitoring of children with Early Onset Scoliosis. However, there is a paucity of literature on the reliability of thoracic and spino-pelvic parameters on EOS imaging in children treated with MCGR.Three independent reviewers independently read a random assortment of 20 whole spine posteroanterior and lateral radiographs from patients treated with MCGR. The measurements were repeated 4 weeks after the initial read. The following radiological parameters were measured: Cobb angle of the main and compensatory curves, coronal balance, coronal T1-S1 and T1-T12 length, chest width and depth at T6, pelvic inlet width, MCGR distracted lengths, global kyphosis, proximal and distal junctional angle, lordosis, sagittal balance, pelvic incidence, pelvic tilt and sacral slope. Statistical analysis was performed with paired t test and Cronbach alpha for inter- and intraobserver reliability.All measurements had good or excellent intra- and interobserver reliability (α0.8; P 0.05), except measurements of the proximal junctional angle which showed only poor intra- and interobserver reliability for patients with an upper instrumented vertebra cranial to T4.EOS imaging is reliable for diagnosis and monitoring of children with Early Onset Scoliosis treated with MCGR. EOS imaging is particularly excellent for assessment of MCGR lengthening. Diagnosis and interpretation of early proximal junctional kyphosis within the cervicothoracic junction should be made with caution.3.

Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine which exhibits morphological changes during growth. The goal of this study was to identify morphological patterns that could be explained by different loading patterns for AIS. Computed tomography data of 21 patients with diagnosed AIS and 48 patients without any visual spinal abnormalities were collected prospectively. The bony structures were reconstructed, and landmarks were placed on characteristic morphological points on the spine. Multiple morphological parameters were calculated based on the distances between the landmarks. The intra- and inter-observer variability for each parameter was estimated. Differences between healthy and scoliotic spines were statistically analysed using the t test for unpaired data, with a significance level of α = 0.01. Within the healthy group, an out-of-plane rotation of the vertebrae in the transverse plane was measured (2.6° ± 4.1° at T2). Relating the length of the spinal curvature to the T1–S1 height of the spine revealed that scoliotic spines were significantly longer. However, the endplate area in the AIS group was significantly smaller once compared to the curvature length. The relation between the left and right pedicle areas varied between 2.5 ± 0.79 and 0.4 ± 0.19, while the ratio of the facet articular surfaces varied within 2.3 ± 0.5 and 0.5 ± 0.2. This study identified a certain morphological pattern along the spine, which reveals a distinct load path prevalent within AIS. The data suggested that the spine adapts to the asymmetric load conditions and the spine is not deformed by asymmetric growth disturbance. These slides can be retrieved under Electronic Supplementary Material.